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![Martin Kustermann](/assets/img/avatar_default.png)
Issue https://dart-review.googlesource.com/c/sdk/+/115701 Change-Id: Ib579f0bbc8d694aec74afd837217316a10baf910 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/115707 Commit-Queue: Martin Kustermann <kustermann@google.com> Reviewed-by: Ryan Macnak <rmacnak@google.com> Reviewed-by: Daco Harkes <dacoharkes@google.com>
5584 lines
212 KiB
C++
5584 lines
212 KiB
C++
// Copyright (c) 2014, the Dart project authors. Please see the AUTHORS file
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// for details. All rights reserved. Use of this source code is governed by a
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// BSD-style license that can be found in the LICENSE file.
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#include "vm/regexp.h"
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#include <memory>
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#include "platform/splay-tree-inl.h"
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#include "platform/unicode.h"
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#include "unicode/uniset.h"
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#include "vm/dart_entry.h"
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#include "vm/regexp_assembler.h"
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#include "vm/regexp_assembler_bytecode.h"
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#include "vm/regexp_assembler_ir.h"
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#include "vm/regexp_ast.h"
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#include "vm/symbols.h"
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#include "vm/thread.h"
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#include "vm/unibrow-inl.h"
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#define Z (zone())
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namespace dart {
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// Default to generating optimized regexp code.
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static const bool kRegexpOptimization = true;
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// More makes code generation slower, less makes V8 benchmark score lower.
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static const intptr_t kMaxLookaheadForBoyerMoore = 8;
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ContainedInLattice AddRange(ContainedInLattice containment,
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const int32_t* ranges,
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intptr_t ranges_length,
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Interval new_range) {
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ASSERT((ranges_length & 1) == 1);
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ASSERT(ranges[ranges_length - 1] == Utf::kMaxCodePoint + 1);
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if (containment == kLatticeUnknown) return containment;
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bool inside = false;
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int32_t last = 0;
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for (intptr_t i = 0; i < ranges_length;
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inside = !inside, last = ranges[i], i++) {
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// Consider the range from last to ranges[i].
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// We haven't got to the new range yet.
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if (ranges[i] <= new_range.from()) continue;
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// New range is wholly inside last-ranges[i]. Note that new_range.to() is
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// inclusive, but the values in ranges are not.
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if (last <= new_range.from() && new_range.to() < ranges[i]) {
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return Combine(containment, inside ? kLatticeIn : kLatticeOut);
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}
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return kLatticeUnknown;
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}
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return containment;
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}
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// -------------------------------------------------------------------
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// Implementation of the Irregexp regular expression engine.
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//
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// The Irregexp regular expression engine is intended to be a complete
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// implementation of ECMAScript regular expressions. It generates
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// IR code that is subsequently compiled to native code.
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// The Irregexp regexp engine is structured in three steps.
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// 1) The parser generates an abstract syntax tree. See regexp_ast.cc.
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// 2) From the AST a node network is created. The nodes are all
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// subclasses of RegExpNode. The nodes represent states when
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// executing a regular expression. Several optimizations are
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// performed on the node network.
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// 3) From the nodes we generate IR instructions that can actually
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// execute the regular expression (perform the search). The
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// code generation step is described in more detail below.
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// Code generation.
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//
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// The nodes are divided into four main categories.
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// * Choice nodes
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// These represent places where the regular expression can
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// match in more than one way. For example on entry to an
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// alternation (foo|bar) or a repetition (*, +, ? or {}).
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// * Action nodes
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// These represent places where some action should be
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// performed. Examples include recording the current position
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// in the input string to a register (in order to implement
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// captures) or other actions on register for example in order
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// to implement the counters needed for {} repetitions.
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// * Matching nodes
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// These attempt to match some element part of the input string.
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// Examples of elements include character classes, plain strings
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// or back references.
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// * End nodes
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// These are used to implement the actions required on finding
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// a successful match or failing to find a match.
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//
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// The code generated maintains some state as it runs. This consists of the
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// following elements:
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//
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// * The capture registers. Used for string captures.
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// * Other registers. Used for counters etc.
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// * The current position.
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// * The stack of backtracking information. Used when a matching node
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// fails to find a match and needs to try an alternative.
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//
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// Conceptual regular expression execution model:
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//
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// There is a simple conceptual model of regular expression execution
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// which will be presented first. The actual code generated is a more
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// efficient simulation of the simple conceptual model:
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//
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// * Choice nodes are implemented as follows:
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// For each choice except the last {
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// push current position
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// push backtrack code location
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// <generate code to test for choice>
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// backtrack code location:
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// pop current position
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// }
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// <generate code to test for last choice>
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//
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// * Actions nodes are generated as follows
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// <push affected registers on backtrack stack>
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// <generate code to perform action>
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// push backtrack code location
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// <generate code to test for following nodes>
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// backtrack code location:
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// <pop affected registers to restore their state>
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// <pop backtrack location from stack and go to it>
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//
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// * Matching nodes are generated as follows:
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// if input string matches at current position
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// update current position
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// <generate code to test for following nodes>
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// else
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// <pop backtrack location from stack and go to it>
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//
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// Thus it can be seen that the current position is saved and restored
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// by the choice nodes, whereas the registers are saved and restored by
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// by the action nodes that manipulate them.
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//
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// The other interesting aspect of this model is that nodes are generated
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// at the point where they are needed by a recursive call to Emit(). If
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// the node has already been code generated then the Emit() call will
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// generate a jump to the previously generated code instead. In order to
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// limit recursion it is possible for the Emit() function to put the node
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// on a work list for later generation and instead generate a jump. The
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// destination of the jump is resolved later when the code is generated.
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//
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// Actual regular expression code generation.
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//
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// Code generation is actually more complicated than the above. In order
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// to improve the efficiency of the generated code some optimizations are
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// performed
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//
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// * Choice nodes have 1-character lookahead.
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// A choice node looks at the following character and eliminates some of
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// the choices immediately based on that character. This is not yet
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// implemented.
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// * Simple greedy loops store reduced backtracking information.
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// A quantifier like /.*foo/m will greedily match the whole input. It will
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// then need to backtrack to a point where it can match "foo". The naive
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// implementation of this would push each character position onto the
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// backtracking stack, then pop them off one by one. This would use space
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// proportional to the length of the input string. However since the "."
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// can only match in one way and always has a constant length (in this case
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// of 1) it suffices to store the current position on the top of the stack
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// once. Matching now becomes merely incrementing the current position and
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// backtracking becomes decrementing the current position and checking the
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// result against the stored current position. This is faster and saves
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// space.
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// * The current state is virtualized.
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// This is used to defer expensive operations until it is clear that they
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// are needed and to generate code for a node more than once, allowing
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// specialized an efficient versions of the code to be created. This is
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// explained in the section below.
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//
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// Execution state virtualization.
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//
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// Instead of emitting code, nodes that manipulate the state can record their
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// manipulation in an object called the Trace. The Trace object can record a
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// current position offset, an optional backtrack code location on the top of
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// the virtualized backtrack stack and some register changes. When a node is
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// to be emitted it can flush the Trace or update it. Flushing the Trace
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// will emit code to bring the actual state into line with the virtual state.
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// Avoiding flushing the state can postpone some work (e.g. updates of capture
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// registers). Postponing work can save time when executing the regular
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// expression since it may be found that the work never has to be done as a
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// failure to match can occur. In addition it is much faster to jump to a
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// known backtrack code location than it is to pop an unknown backtrack
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// location from the stack and jump there.
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//
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// The virtual state found in the Trace affects code generation. For example
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// the virtual state contains the difference between the actual current
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// position and the virtual current position, and matching code needs to use
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// this offset to attempt a match in the correct location of the input
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// string. Therefore code generated for a non-trivial trace is specialized
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// to that trace. The code generator therefore has the ability to generate
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// code for each node several times. In order to limit the size of the
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// generated code there is an arbitrary limit on how many specialized sets of
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// code may be generated for a given node. If the limit is reached, the
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// trace is flushed and a generic version of the code for a node is emitted.
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// This is subsequently used for that node. The code emitted for non-generic
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// trace is not recorded in the node and so it cannot currently be reused in
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// the event that code generation is requested for an identical trace.
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void RegExpTree::AppendToText(RegExpText* text) {
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UNREACHABLE();
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}
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void RegExpAtom::AppendToText(RegExpText* text) {
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text->AddElement(TextElement::Atom(this));
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}
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void RegExpCharacterClass::AppendToText(RegExpText* text) {
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text->AddElement(TextElement::CharClass(this));
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}
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void RegExpText::AppendToText(RegExpText* text) {
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for (intptr_t i = 0; i < elements()->length(); i++)
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text->AddElement((*elements())[i]);
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}
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TextElement TextElement::Atom(RegExpAtom* atom) {
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return TextElement(ATOM, atom);
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}
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TextElement TextElement::CharClass(RegExpCharacterClass* char_class) {
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return TextElement(CHAR_CLASS, char_class);
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}
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intptr_t TextElement::length() const {
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switch (text_type()) {
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case ATOM:
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return atom()->length();
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case CHAR_CLASS:
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return 1;
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}
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UNREACHABLE();
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return 0;
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}
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class FrequencyCollator : public ValueObject {
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public:
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FrequencyCollator() : total_samples_(0) {
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for (intptr_t i = 0; i < RegExpMacroAssembler::kTableSize; i++) {
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frequencies_[i] = CharacterFrequency(i);
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}
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}
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void CountCharacter(intptr_t character) {
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intptr_t index = (character & RegExpMacroAssembler::kTableMask);
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frequencies_[index].Increment();
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total_samples_++;
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}
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// Does not measure in percent, but rather per-128 (the table size from the
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// regexp macro assembler).
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intptr_t Frequency(intptr_t in_character) {
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ASSERT((in_character & RegExpMacroAssembler::kTableMask) == in_character);
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if (total_samples_ < 1) return 1; // Division by zero.
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intptr_t freq_in_per128 =
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(frequencies_[in_character].counter() * 128) / total_samples_;
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return freq_in_per128;
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}
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private:
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class CharacterFrequency {
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public:
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CharacterFrequency() : counter_(0), character_(-1) {}
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explicit CharacterFrequency(intptr_t character)
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: counter_(0), character_(character) {}
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void Increment() { counter_++; }
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intptr_t counter() { return counter_; }
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intptr_t character() { return character_; }
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private:
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intptr_t counter_;
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intptr_t character_;
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DISALLOW_ALLOCATION();
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};
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private:
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CharacterFrequency frequencies_[RegExpMacroAssembler::kTableSize];
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intptr_t total_samples_;
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};
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class RegExpCompiler : public ValueObject {
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public:
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RegExpCompiler(intptr_t capture_count, bool is_one_byte);
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intptr_t AllocateRegister() { return next_register_++; }
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// Lookarounds to match lone surrogates for unicode character class matches
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// are never nested. We can therefore reuse registers.
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intptr_t UnicodeLookaroundStackRegister() {
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if (unicode_lookaround_stack_register_ == kNoRegister) {
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unicode_lookaround_stack_register_ = AllocateRegister();
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}
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return unicode_lookaround_stack_register_;
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}
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intptr_t UnicodeLookaroundPositionRegister() {
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if (unicode_lookaround_position_register_ == kNoRegister) {
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unicode_lookaround_position_register_ = AllocateRegister();
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}
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return unicode_lookaround_position_register_;
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}
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#if !defined(DART_PRECOMPILED_RUNTIME)
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RegExpEngine::CompilationResult Assemble(IRRegExpMacroAssembler* assembler,
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RegExpNode* start,
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intptr_t capture_count,
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const String& pattern);
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#endif
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RegExpEngine::CompilationResult Assemble(
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BytecodeRegExpMacroAssembler* assembler,
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RegExpNode* start,
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intptr_t capture_count,
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const String& pattern);
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inline void AddWork(RegExpNode* node) { work_list_->Add(node); }
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static const intptr_t kImplementationOffset = 0;
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static const intptr_t kNumberOfRegistersOffset = 0;
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static const intptr_t kCodeOffset = 1;
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RegExpMacroAssembler* macro_assembler() { return macro_assembler_; }
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EndNode* accept() { return accept_; }
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static const intptr_t kMaxRecursion = 100;
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inline intptr_t recursion_depth() { return recursion_depth_; }
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inline void IncrementRecursionDepth() { recursion_depth_++; }
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inline void DecrementRecursionDepth() { recursion_depth_--; }
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void SetRegExpTooBig() { reg_exp_too_big_ = true; }
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inline bool one_byte() const { return is_one_byte_; }
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bool read_backward() { return read_backward_; }
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void set_read_backward(bool value) { read_backward_ = value; }
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FrequencyCollator* frequency_collator() { return &frequency_collator_; }
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intptr_t current_expansion_factor() { return current_expansion_factor_; }
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void set_current_expansion_factor(intptr_t value) {
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current_expansion_factor_ = value;
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}
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Zone* zone() const { return zone_; }
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static const intptr_t kNoRegister = -1;
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private:
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EndNode* accept_;
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intptr_t next_register_;
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intptr_t unicode_lookaround_stack_register_;
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intptr_t unicode_lookaround_position_register_;
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ZoneGrowableArray<RegExpNode*>* work_list_;
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intptr_t recursion_depth_;
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RegExpMacroAssembler* macro_assembler_;
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bool is_one_byte_;
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bool reg_exp_too_big_;
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bool read_backward_;
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intptr_t current_expansion_factor_;
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FrequencyCollator frequency_collator_;
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Zone* zone_;
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};
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class RecursionCheck : public ValueObject {
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public:
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explicit RecursionCheck(RegExpCompiler* compiler) : compiler_(compiler) {
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compiler->IncrementRecursionDepth();
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}
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~RecursionCheck() { compiler_->DecrementRecursionDepth(); }
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private:
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RegExpCompiler* compiler_;
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};
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static RegExpEngine::CompilationResult IrregexpRegExpTooBig() {
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return RegExpEngine::CompilationResult("RegExp too big");
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}
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// Attempts to compile the regexp using an Irregexp code generator. Returns
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// a fixed array or a null handle depending on whether it succeeded.
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RegExpCompiler::RegExpCompiler(intptr_t capture_count, bool is_one_byte)
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: next_register_(2 * (capture_count + 1)),
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unicode_lookaround_stack_register_(kNoRegister),
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unicode_lookaround_position_register_(kNoRegister),
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work_list_(NULL),
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recursion_depth_(0),
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is_one_byte_(is_one_byte),
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reg_exp_too_big_(false),
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read_backward_(false),
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current_expansion_factor_(1),
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zone_(Thread::Current()->zone()) {
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accept_ = new (Z) EndNode(EndNode::ACCEPT, Z);
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}
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#if !defined(DART_PRECOMPILED_RUNTIME)
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RegExpEngine::CompilationResult RegExpCompiler::Assemble(
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IRRegExpMacroAssembler* macro_assembler,
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RegExpNode* start,
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intptr_t capture_count,
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const String& pattern) {
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macro_assembler->set_slow_safe(false /* use_slow_safe_regexp_compiler */);
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macro_assembler_ = macro_assembler;
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ZoneGrowableArray<RegExpNode*> work_list(0);
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work_list_ = &work_list;
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BlockLabel fail;
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macro_assembler_->PushBacktrack(&fail);
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Trace new_trace;
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start->Emit(this, &new_trace);
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macro_assembler_->BindBlock(&fail);
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macro_assembler_->Fail();
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while (!work_list.is_empty()) {
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work_list.RemoveLast()->Emit(this, &new_trace);
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}
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if (reg_exp_too_big_) return IrregexpRegExpTooBig();
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macro_assembler->GenerateBacktrackBlock();
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macro_assembler->FinalizeRegistersArray();
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return RegExpEngine::CompilationResult(
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macro_assembler->backtrack_goto(), macro_assembler->graph_entry(),
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macro_assembler->num_blocks(), macro_assembler->num_stack_locals(),
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next_register_);
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}
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#endif
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RegExpEngine::CompilationResult RegExpCompiler::Assemble(
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BytecodeRegExpMacroAssembler* macro_assembler,
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RegExpNode* start,
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intptr_t capture_count,
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const String& pattern) {
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macro_assembler->set_slow_safe(false /* use_slow_safe_regexp_compiler */);
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macro_assembler_ = macro_assembler;
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ZoneGrowableArray<RegExpNode*> work_list(0);
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work_list_ = &work_list;
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BlockLabel fail;
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macro_assembler_->PushBacktrack(&fail);
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Trace new_trace;
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start->Emit(this, &new_trace);
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macro_assembler_->BindBlock(&fail);
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macro_assembler_->Fail();
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while (!work_list.is_empty()) {
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work_list.RemoveLast()->Emit(this, &new_trace);
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}
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if (reg_exp_too_big_) return IrregexpRegExpTooBig();
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TypedData& bytecode = TypedData::ZoneHandle(macro_assembler->GetBytecode());
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return RegExpEngine::CompilationResult(&bytecode, next_register_);
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}
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bool Trace::DeferredAction::Mentions(intptr_t that) {
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if (action_type() == ActionNode::CLEAR_CAPTURES) {
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Interval range = static_cast<DeferredClearCaptures*>(this)->range();
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return range.Contains(that);
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} else {
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return reg() == that;
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}
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}
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bool Trace::mentions_reg(intptr_t reg) {
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for (DeferredAction* action = actions_; action != NULL;
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action = action->next()) {
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if (action->Mentions(reg)) return true;
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}
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return false;
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}
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bool Trace::GetStoredPosition(intptr_t reg, intptr_t* cp_offset) {
|
|
ASSERT(*cp_offset == 0);
|
|
for (DeferredAction* action = actions_; action != NULL;
|
|
action = action->next()) {
|
|
if (action->Mentions(reg)) {
|
|
if (action->action_type() == ActionNode::STORE_POSITION) {
|
|
*cp_offset = static_cast<DeferredCapture*>(action)->cp_offset();
|
|
return true;
|
|
} else {
|
|
return false;
|
|
}
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
// This is called as we come into a loop choice node and some other tricky
|
|
// nodes. It normalizes the state of the code generator to ensure we can
|
|
// generate generic code.
|
|
intptr_t Trace::FindAffectedRegisters(OutSet* affected_registers, Zone* zone) {
|
|
intptr_t max_register = RegExpCompiler::kNoRegister;
|
|
for (DeferredAction* action = actions_; action != NULL;
|
|
action = action->next()) {
|
|
if (action->action_type() == ActionNode::CLEAR_CAPTURES) {
|
|
Interval range = static_cast<DeferredClearCaptures*>(action)->range();
|
|
for (intptr_t i = range.from(); i <= range.to(); i++)
|
|
affected_registers->Set(i, zone);
|
|
if (range.to() > max_register) max_register = range.to();
|
|
} else {
|
|
affected_registers->Set(action->reg(), zone);
|
|
if (action->reg() > max_register) max_register = action->reg();
|
|
}
|
|
}
|
|
return max_register;
|
|
}
|
|
|
|
void Trace::RestoreAffectedRegisters(RegExpMacroAssembler* assembler,
|
|
intptr_t max_register,
|
|
const OutSet& registers_to_pop,
|
|
const OutSet& registers_to_clear) {
|
|
for (intptr_t reg = max_register; reg >= 0; reg--) {
|
|
if (registers_to_pop.Get(reg)) {
|
|
assembler->PopRegister(reg);
|
|
} else if (registers_to_clear.Get(reg)) {
|
|
intptr_t clear_to = reg;
|
|
while (reg > 0 && registers_to_clear.Get(reg - 1)) {
|
|
reg--;
|
|
}
|
|
assembler->ClearRegisters(reg, clear_to);
|
|
}
|
|
}
|
|
}
|
|
|
|
void Trace::PerformDeferredActions(RegExpMacroAssembler* assembler,
|
|
intptr_t max_register,
|
|
const OutSet& affected_registers,
|
|
OutSet* registers_to_pop,
|
|
OutSet* registers_to_clear,
|
|
Zone* zone) {
|
|
for (intptr_t reg = 0; reg <= max_register; reg++) {
|
|
if (!affected_registers.Get(reg)) {
|
|
continue;
|
|
}
|
|
|
|
// The chronologically first deferred action in the trace
|
|
// is used to infer the action needed to restore a register
|
|
// to its previous state (or not, if it's safe to ignore it).
|
|
enum DeferredActionUndoType { ACTION_IGNORE, ACTION_RESTORE, ACTION_CLEAR };
|
|
DeferredActionUndoType undo_action = ACTION_IGNORE;
|
|
|
|
intptr_t value = 0;
|
|
bool absolute = false;
|
|
bool clear = false;
|
|
static const intptr_t kNoStore = kMinInt32;
|
|
intptr_t store_position = kNoStore;
|
|
// This is a little tricky because we are scanning the actions in reverse
|
|
// historical order (newest first).
|
|
for (DeferredAction* action = actions_; action != NULL;
|
|
action = action->next()) {
|
|
if (action->Mentions(reg)) {
|
|
switch (action->action_type()) {
|
|
case ActionNode::SET_REGISTER: {
|
|
Trace::DeferredSetRegister* psr =
|
|
static_cast<Trace::DeferredSetRegister*>(action);
|
|
if (!absolute) {
|
|
value += psr->value();
|
|
absolute = true;
|
|
}
|
|
// SET_REGISTER is currently only used for newly introduced loop
|
|
// counters. They can have a significant previous value if they
|
|
// occour in a loop. TODO(lrn): Propagate this information, so we
|
|
// can set undo_action to ACTION_IGNORE if we know there is no
|
|
// value to restore.
|
|
undo_action = ACTION_RESTORE;
|
|
ASSERT(store_position == kNoStore);
|
|
ASSERT(!clear);
|
|
break;
|
|
}
|
|
case ActionNode::INCREMENT_REGISTER:
|
|
if (!absolute) {
|
|
value++;
|
|
}
|
|
ASSERT(store_position == kNoStore);
|
|
ASSERT(!clear);
|
|
undo_action = ACTION_RESTORE;
|
|
break;
|
|
case ActionNode::STORE_POSITION: {
|
|
Trace::DeferredCapture* pc =
|
|
static_cast<Trace::DeferredCapture*>(action);
|
|
if (!clear && store_position == kNoStore) {
|
|
store_position = pc->cp_offset();
|
|
}
|
|
|
|
// For captures we know that stores and clears alternate.
|
|
// Other register, are never cleared, and if the occur
|
|
// inside a loop, they might be assigned more than once.
|
|
if (reg <= 1) {
|
|
// Registers zero and one, aka "capture zero", is
|
|
// always set correctly if we succeed. There is no
|
|
// need to undo a setting on backtrack, because we
|
|
// will set it again or fail.
|
|
undo_action = ACTION_IGNORE;
|
|
} else {
|
|
undo_action = pc->is_capture() ? ACTION_CLEAR : ACTION_RESTORE;
|
|
}
|
|
ASSERT(!absolute);
|
|
ASSERT(value == 0);
|
|
break;
|
|
}
|
|
case ActionNode::CLEAR_CAPTURES: {
|
|
// Since we're scanning in reverse order, if we've already
|
|
// set the position we have to ignore historically earlier
|
|
// clearing operations.
|
|
if (store_position == kNoStore) {
|
|
clear = true;
|
|
}
|
|
undo_action = ACTION_RESTORE;
|
|
ASSERT(!absolute);
|
|
ASSERT(value == 0);
|
|
break;
|
|
}
|
|
default:
|
|
UNREACHABLE();
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
// Prepare for the undo-action (e.g., push if it's going to be popped).
|
|
if (undo_action == ACTION_RESTORE) {
|
|
assembler->PushRegister(reg);
|
|
registers_to_pop->Set(reg, zone);
|
|
} else if (undo_action == ACTION_CLEAR) {
|
|
registers_to_clear->Set(reg, zone);
|
|
}
|
|
// Perform the chronologically last action (or accumulated increment)
|
|
// for the register.
|
|
if (store_position != kNoStore) {
|
|
assembler->WriteCurrentPositionToRegister(reg, store_position);
|
|
} else if (clear) {
|
|
assembler->ClearRegisters(reg, reg);
|
|
} else if (absolute) {
|
|
assembler->SetRegister(reg, value);
|
|
} else if (value != 0) {
|
|
assembler->AdvanceRegister(reg, value);
|
|
}
|
|
}
|
|
}
|
|
|
|
// This is called as we come into a loop choice node and some other tricky
|
|
// nodes. It normalizes the state of the code generator to ensure we can
|
|
// generate generic code.
|
|
void Trace::Flush(RegExpCompiler* compiler, RegExpNode* successor) {
|
|
RegExpMacroAssembler* assembler = compiler->macro_assembler();
|
|
|
|
ASSERT(!is_trivial());
|
|
|
|
if (actions_ == NULL && backtrack() == NULL) {
|
|
// Here we just have some deferred cp advances to fix and we are back to
|
|
// a normal situation. We may also have to forget some information gained
|
|
// through a quick check that was already performed.
|
|
if (cp_offset_ != 0) assembler->AdvanceCurrentPosition(cp_offset_);
|
|
// Create a new trivial state and generate the node with that.
|
|
Trace new_state;
|
|
successor->Emit(compiler, &new_state);
|
|
return;
|
|
}
|
|
|
|
// Generate deferred actions here along with code to undo them again.
|
|
OutSet affected_registers;
|
|
|
|
if (backtrack() != NULL) {
|
|
// Here we have a concrete backtrack location. These are set up by choice
|
|
// nodes and so they indicate that we have a deferred save of the current
|
|
// position which we may need to emit here.
|
|
assembler->PushCurrentPosition();
|
|
}
|
|
Zone* zone = successor->zone();
|
|
intptr_t max_register = FindAffectedRegisters(&affected_registers, zone);
|
|
OutSet registers_to_pop;
|
|
OutSet registers_to_clear;
|
|
PerformDeferredActions(assembler, max_register, affected_registers,
|
|
®isters_to_pop, ®isters_to_clear, zone);
|
|
if (cp_offset_ != 0) {
|
|
assembler->AdvanceCurrentPosition(cp_offset_);
|
|
}
|
|
|
|
// Create a new trivial state and generate the node with that.
|
|
BlockLabel undo;
|
|
assembler->PushBacktrack(&undo);
|
|
Trace new_state;
|
|
successor->Emit(compiler, &new_state);
|
|
|
|
// On backtrack we need to restore state.
|
|
assembler->BindBlock(&undo);
|
|
RestoreAffectedRegisters(assembler, max_register, registers_to_pop,
|
|
registers_to_clear);
|
|
if (backtrack() == NULL) {
|
|
assembler->Backtrack();
|
|
} else {
|
|
assembler->PopCurrentPosition();
|
|
assembler->GoTo(backtrack());
|
|
}
|
|
}
|
|
|
|
void NegativeSubmatchSuccess::Emit(RegExpCompiler* compiler, Trace* trace) {
|
|
RegExpMacroAssembler* assembler = compiler->macro_assembler();
|
|
|
|
// Omit flushing the trace. We discard the entire stack frame anyway.
|
|
|
|
if (!label()->IsBound()) {
|
|
// We are completely independent of the trace, since we ignore it,
|
|
// so this code can be used as the generic version.
|
|
assembler->BindBlock(label());
|
|
}
|
|
|
|
// Throw away everything on the backtrack stack since the start
|
|
// of the negative submatch and restore the character position.
|
|
assembler->ReadCurrentPositionFromRegister(current_position_register_);
|
|
assembler->ReadStackPointerFromRegister(stack_pointer_register_);
|
|
if (clear_capture_count_ > 0) {
|
|
// Clear any captures that might have been performed during the success
|
|
// of the body of the negative look-ahead.
|
|
int clear_capture_end = clear_capture_start_ + clear_capture_count_ - 1;
|
|
assembler->ClearRegisters(clear_capture_start_, clear_capture_end);
|
|
}
|
|
// Now that we have unwound the stack we find at the top of the stack the
|
|
// backtrack that the BeginSubmatch node got.
|
|
assembler->Backtrack();
|
|
}
|
|
|
|
void EndNode::Emit(RegExpCompiler* compiler, Trace* trace) {
|
|
if (!trace->is_trivial()) {
|
|
trace->Flush(compiler, this);
|
|
return;
|
|
}
|
|
RegExpMacroAssembler* assembler = compiler->macro_assembler();
|
|
if (!label()->IsBound()) {
|
|
assembler->BindBlock(label());
|
|
}
|
|
switch (action_) {
|
|
case ACCEPT:
|
|
assembler->Succeed();
|
|
return;
|
|
case BACKTRACK:
|
|
assembler->GoTo(trace->backtrack());
|
|
return;
|
|
case NEGATIVE_SUBMATCH_SUCCESS:
|
|
// This case is handled in a different virtual method.
|
|
UNREACHABLE();
|
|
}
|
|
UNIMPLEMENTED();
|
|
}
|
|
|
|
void GuardedAlternative::AddGuard(Guard* guard, Zone* zone) {
|
|
if (guards_ == NULL) guards_ = new (zone) ZoneGrowableArray<Guard*>(1);
|
|
guards_->Add(guard);
|
|
}
|
|
|
|
ActionNode* ActionNode::SetRegister(intptr_t reg,
|
|
intptr_t val,
|
|
RegExpNode* on_success) {
|
|
ActionNode* result =
|
|
new (on_success->zone()) ActionNode(SET_REGISTER, on_success);
|
|
result->data_.u_store_register.reg = reg;
|
|
result->data_.u_store_register.value = val;
|
|
return result;
|
|
}
|
|
|
|
ActionNode* ActionNode::IncrementRegister(intptr_t reg,
|
|
RegExpNode* on_success) {
|
|
ActionNode* result =
|
|
new (on_success->zone()) ActionNode(INCREMENT_REGISTER, on_success);
|
|
result->data_.u_increment_register.reg = reg;
|
|
return result;
|
|
}
|
|
|
|
ActionNode* ActionNode::StorePosition(intptr_t reg,
|
|
bool is_capture,
|
|
RegExpNode* on_success) {
|
|
ActionNode* result =
|
|
new (on_success->zone()) ActionNode(STORE_POSITION, on_success);
|
|
result->data_.u_position_register.reg = reg;
|
|
result->data_.u_position_register.is_capture = is_capture;
|
|
return result;
|
|
}
|
|
|
|
ActionNode* ActionNode::ClearCaptures(Interval range, RegExpNode* on_success) {
|
|
ActionNode* result =
|
|
new (on_success->zone()) ActionNode(CLEAR_CAPTURES, on_success);
|
|
result->data_.u_clear_captures.range_from = range.from();
|
|
result->data_.u_clear_captures.range_to = range.to();
|
|
return result;
|
|
}
|
|
|
|
ActionNode* ActionNode::BeginSubmatch(intptr_t stack_reg,
|
|
intptr_t position_reg,
|
|
RegExpNode* on_success) {
|
|
ActionNode* result =
|
|
new (on_success->zone()) ActionNode(BEGIN_SUBMATCH, on_success);
|
|
result->data_.u_submatch.stack_pointer_register = stack_reg;
|
|
result->data_.u_submatch.current_position_register = position_reg;
|
|
return result;
|
|
}
|
|
|
|
ActionNode* ActionNode::PositiveSubmatchSuccess(intptr_t stack_reg,
|
|
intptr_t position_reg,
|
|
intptr_t clear_register_count,
|
|
intptr_t clear_register_from,
|
|
RegExpNode* on_success) {
|
|
ActionNode* result = new (on_success->zone())
|
|
ActionNode(POSITIVE_SUBMATCH_SUCCESS, on_success);
|
|
result->data_.u_submatch.stack_pointer_register = stack_reg;
|
|
result->data_.u_submatch.current_position_register = position_reg;
|
|
result->data_.u_submatch.clear_register_count = clear_register_count;
|
|
result->data_.u_submatch.clear_register_from = clear_register_from;
|
|
return result;
|
|
}
|
|
|
|
ActionNode* ActionNode::EmptyMatchCheck(intptr_t start_register,
|
|
intptr_t repetition_register,
|
|
intptr_t repetition_limit,
|
|
RegExpNode* on_success) {
|
|
ActionNode* result =
|
|
new (on_success->zone()) ActionNode(EMPTY_MATCH_CHECK, on_success);
|
|
result->data_.u_empty_match_check.start_register = start_register;
|
|
result->data_.u_empty_match_check.repetition_register = repetition_register;
|
|
result->data_.u_empty_match_check.repetition_limit = repetition_limit;
|
|
return result;
|
|
}
|
|
|
|
#define DEFINE_ACCEPT(Type) \
|
|
void Type##Node::Accept(NodeVisitor* visitor) { visitor->Visit##Type(this); }
|
|
FOR_EACH_NODE_TYPE(DEFINE_ACCEPT)
|
|
#undef DEFINE_ACCEPT
|
|
|
|
void LoopChoiceNode::Accept(NodeVisitor* visitor) {
|
|
visitor->VisitLoopChoice(this);
|
|
}
|
|
|
|
// -------------------------------------------------------------------
|
|
// Emit code.
|
|
|
|
void ChoiceNode::GenerateGuard(RegExpMacroAssembler* macro_assembler,
|
|
Guard* guard,
|
|
Trace* trace) {
|
|
switch (guard->op()) {
|
|
case Guard::LT:
|
|
ASSERT(!trace->mentions_reg(guard->reg()));
|
|
macro_assembler->IfRegisterGE(guard->reg(), guard->value(),
|
|
trace->backtrack());
|
|
break;
|
|
case Guard::GEQ:
|
|
ASSERT(!trace->mentions_reg(guard->reg()));
|
|
macro_assembler->IfRegisterLT(guard->reg(), guard->value(),
|
|
trace->backtrack());
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Returns the number of characters in the equivalence class, omitting those
|
|
// that cannot occur in the source string because it is ASCII.
|
|
static intptr_t GetCaseIndependentLetters(uint16_t character,
|
|
bool one_byte_subject,
|
|
int32_t* letters) {
|
|
unibrow::Mapping<unibrow::Ecma262UnCanonicalize> jsregexp_uncanonicalize;
|
|
intptr_t length = jsregexp_uncanonicalize.get(character, '\0', letters);
|
|
// Unibrow returns 0 or 1 for characters where case independence is
|
|
// trivial.
|
|
if (length == 0) {
|
|
letters[0] = character;
|
|
length = 1;
|
|
}
|
|
if (!one_byte_subject || character <= Symbols::kMaxOneCharCodeSymbol) {
|
|
return length;
|
|
}
|
|
|
|
// The standard requires that non-ASCII characters cannot have ASCII
|
|
// character codes in their equivalence class.
|
|
// TODO(dcarney): issue 3550 this is not actually true for Latin1 anymore,
|
|
// is it? For example, \u00C5 is equivalent to \u212B.
|
|
return 0;
|
|
}
|
|
|
|
static inline bool EmitSimpleCharacter(Zone* zone,
|
|
RegExpCompiler* compiler,
|
|
uint16_t c,
|
|
BlockLabel* on_failure,
|
|
intptr_t cp_offset,
|
|
bool check,
|
|
bool preloaded) {
|
|
RegExpMacroAssembler* assembler = compiler->macro_assembler();
|
|
bool bound_checked = false;
|
|
if (!preloaded) {
|
|
assembler->LoadCurrentCharacter(cp_offset, on_failure, check);
|
|
bound_checked = true;
|
|
}
|
|
assembler->CheckNotCharacter(c, on_failure);
|
|
return bound_checked;
|
|
}
|
|
|
|
// Only emits non-letters (things that don't have case). Only used for case
|
|
// independent matches.
|
|
static inline bool EmitAtomNonLetter(Zone* zone,
|
|
RegExpCompiler* compiler,
|
|
uint16_t c,
|
|
BlockLabel* on_failure,
|
|
intptr_t cp_offset,
|
|
bool check,
|
|
bool preloaded) {
|
|
RegExpMacroAssembler* macro_assembler = compiler->macro_assembler();
|
|
bool one_byte = compiler->one_byte();
|
|
int32_t chars[unibrow::Ecma262UnCanonicalize::kMaxWidth];
|
|
intptr_t length = GetCaseIndependentLetters(c, one_byte, chars);
|
|
if (length < 1) {
|
|
// This can't match. Must be an one-byte subject and a non-one-byte
|
|
// character. We do not need to do anything since the one-byte pass
|
|
// already handled this.
|
|
return false; // Bounds not checked.
|
|
}
|
|
bool checked = false;
|
|
// We handle the length > 1 case in a later pass.
|
|
if (length == 1) {
|
|
if (one_byte && c > Symbols::kMaxOneCharCodeSymbol) {
|
|
// Can't match - see above.
|
|
return false; // Bounds not checked.
|
|
}
|
|
if (!preloaded) {
|
|
macro_assembler->LoadCurrentCharacter(cp_offset, on_failure, check);
|
|
checked = check;
|
|
}
|
|
macro_assembler->CheckNotCharacter(c, on_failure);
|
|
}
|
|
return checked;
|
|
}
|
|
|
|
static bool ShortCutEmitCharacterPair(RegExpMacroAssembler* macro_assembler,
|
|
bool one_byte,
|
|
uint16_t c1,
|
|
uint16_t c2,
|
|
BlockLabel* on_failure) {
|
|
uint16_t char_mask;
|
|
if (one_byte) {
|
|
char_mask = Symbols::kMaxOneCharCodeSymbol;
|
|
} else {
|
|
char_mask = Utf16::kMaxCodeUnit;
|
|
}
|
|
uint16_t exor = c1 ^ c2;
|
|
// Check whether exor has only one bit set.
|
|
if (((exor - 1) & exor) == 0) {
|
|
// If c1 and c2 differ only by one bit.
|
|
// Ecma262UnCanonicalize always gives the highest number last.
|
|
ASSERT(c2 > c1);
|
|
uint16_t mask = char_mask ^ exor;
|
|
macro_assembler->CheckNotCharacterAfterAnd(c1, mask, on_failure);
|
|
return true;
|
|
}
|
|
ASSERT(c2 > c1);
|
|
uint16_t diff = c2 - c1;
|
|
if (((diff - 1) & diff) == 0 && c1 >= diff) {
|
|
// If the characters differ by 2^n but don't differ by one bit then
|
|
// subtract the difference from the found character, then do the or
|
|
// trick. We avoid the theoretical case where negative numbers are
|
|
// involved in order to simplify code generation.
|
|
uint16_t mask = char_mask ^ diff;
|
|
macro_assembler->CheckNotCharacterAfterMinusAnd(c1 - diff, diff, mask,
|
|
on_failure);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
typedef bool EmitCharacterFunction(Zone* zone,
|
|
RegExpCompiler* compiler,
|
|
uint16_t c,
|
|
BlockLabel* on_failure,
|
|
intptr_t cp_offset,
|
|
bool check,
|
|
bool preloaded);
|
|
|
|
// Only emits letters (things that have case). Only used for case independent
|
|
// matches.
|
|
static inline bool EmitAtomLetter(Zone* zone,
|
|
RegExpCompiler* compiler,
|
|
uint16_t c,
|
|
BlockLabel* on_failure,
|
|
intptr_t cp_offset,
|
|
bool check,
|
|
bool preloaded) {
|
|
RegExpMacroAssembler* macro_assembler = compiler->macro_assembler();
|
|
bool one_byte = compiler->one_byte();
|
|
int32_t chars[unibrow::Ecma262UnCanonicalize::kMaxWidth];
|
|
intptr_t length = GetCaseIndependentLetters(c, one_byte, chars);
|
|
if (length <= 1) return false;
|
|
// We may not need to check against the end of the input string
|
|
// if this character lies before a character that matched.
|
|
if (!preloaded) {
|
|
macro_assembler->LoadCurrentCharacter(cp_offset, on_failure, check);
|
|
}
|
|
BlockLabel ok;
|
|
ASSERT(unibrow::Ecma262UnCanonicalize::kMaxWidth == 4);
|
|
switch (length) {
|
|
case 2: {
|
|
if (ShortCutEmitCharacterPair(macro_assembler, one_byte, chars[0],
|
|
chars[1], on_failure)) {
|
|
} else {
|
|
macro_assembler->CheckCharacter(chars[0], &ok);
|
|
macro_assembler->CheckNotCharacter(chars[1], on_failure);
|
|
macro_assembler->BindBlock(&ok);
|
|
}
|
|
break;
|
|
}
|
|
case 4:
|
|
macro_assembler->CheckCharacter(chars[3], &ok);
|
|
FALL_THROUGH;
|
|
case 3:
|
|
macro_assembler->CheckCharacter(chars[0], &ok);
|
|
macro_assembler->CheckCharacter(chars[1], &ok);
|
|
macro_assembler->CheckNotCharacter(chars[2], on_failure);
|
|
macro_assembler->BindBlock(&ok);
|
|
break;
|
|
default:
|
|
UNREACHABLE();
|
|
break;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
static void EmitBoundaryTest(RegExpMacroAssembler* masm,
|
|
uint16_t border,
|
|
BlockLabel* fall_through,
|
|
BlockLabel* above_or_equal,
|
|
BlockLabel* below) {
|
|
if (below != fall_through) {
|
|
masm->CheckCharacterLT(border, below);
|
|
if (above_or_equal != fall_through) masm->GoTo(above_or_equal);
|
|
} else {
|
|
masm->CheckCharacterGT(border - 1, above_or_equal);
|
|
}
|
|
}
|
|
|
|
static void EmitDoubleBoundaryTest(RegExpMacroAssembler* masm,
|
|
uint16_t first,
|
|
uint16_t last,
|
|
BlockLabel* fall_through,
|
|
BlockLabel* in_range,
|
|
BlockLabel* out_of_range) {
|
|
if (in_range == fall_through) {
|
|
if (first == last) {
|
|
masm->CheckNotCharacter(first, out_of_range);
|
|
} else {
|
|
masm->CheckCharacterNotInRange(first, last, out_of_range);
|
|
}
|
|
} else {
|
|
if (first == last) {
|
|
masm->CheckCharacter(first, in_range);
|
|
} else {
|
|
masm->CheckCharacterInRange(first, last, in_range);
|
|
}
|
|
if (out_of_range != fall_through) masm->GoTo(out_of_range);
|
|
}
|
|
}
|
|
|
|
// even_label is for ranges[i] to ranges[i + 1] where i - start_index is even.
|
|
// odd_label is for ranges[i] to ranges[i + 1] where i - start_index is odd.
|
|
static void EmitUseLookupTable(RegExpMacroAssembler* masm,
|
|
ZoneGrowableArray<uint16_t>* ranges,
|
|
intptr_t start_index,
|
|
intptr_t end_index,
|
|
uint16_t min_char,
|
|
BlockLabel* fall_through,
|
|
BlockLabel* even_label,
|
|
BlockLabel* odd_label) {
|
|
static const intptr_t kSize = RegExpMacroAssembler::kTableSize;
|
|
static const intptr_t kMask = RegExpMacroAssembler::kTableMask;
|
|
|
|
intptr_t base = (min_char & ~kMask);
|
|
|
|
// Assert that everything is on one kTableSize page.
|
|
for (intptr_t i = start_index; i <= end_index; i++) {
|
|
ASSERT((ranges->At(i) & ~kMask) == base);
|
|
}
|
|
ASSERT(start_index == 0 || (ranges->At(start_index - 1) & ~kMask) <= base);
|
|
|
|
char templ[kSize];
|
|
BlockLabel* on_bit_set;
|
|
BlockLabel* on_bit_clear;
|
|
intptr_t bit;
|
|
if (even_label == fall_through) {
|
|
on_bit_set = odd_label;
|
|
on_bit_clear = even_label;
|
|
bit = 1;
|
|
} else {
|
|
on_bit_set = even_label;
|
|
on_bit_clear = odd_label;
|
|
bit = 0;
|
|
}
|
|
for (intptr_t i = 0; i < (ranges->At(start_index) & kMask) && i < kSize;
|
|
i++) {
|
|
templ[i] = bit;
|
|
}
|
|
intptr_t j = 0;
|
|
bit ^= 1;
|
|
for (intptr_t i = start_index; i < end_index; i++) {
|
|
for (j = (ranges->At(i) & kMask); j < (ranges->At(i + 1) & kMask); j++) {
|
|
templ[j] = bit;
|
|
}
|
|
bit ^= 1;
|
|
}
|
|
for (intptr_t i = j; i < kSize; i++) {
|
|
templ[i] = bit;
|
|
}
|
|
// TODO(erikcorry): Cache these.
|
|
const TypedData& ba = TypedData::ZoneHandle(
|
|
masm->zone(), TypedData::New(kTypedDataUint8ArrayCid, kSize, Heap::kOld));
|
|
for (intptr_t i = 0; i < kSize; i++) {
|
|
ba.SetUint8(i, templ[i]);
|
|
}
|
|
masm->CheckBitInTable(ba, on_bit_set);
|
|
if (on_bit_clear != fall_through) masm->GoTo(on_bit_clear);
|
|
}
|
|
|
|
static void CutOutRange(RegExpMacroAssembler* masm,
|
|
ZoneGrowableArray<uint16_t>* ranges,
|
|
intptr_t start_index,
|
|
intptr_t end_index,
|
|
intptr_t cut_index,
|
|
BlockLabel* even_label,
|
|
BlockLabel* odd_label) {
|
|
bool odd = (((cut_index - start_index) & 1) == 1);
|
|
BlockLabel* in_range_label = odd ? odd_label : even_label;
|
|
BlockLabel dummy;
|
|
EmitDoubleBoundaryTest(masm, ranges->At(cut_index),
|
|
ranges->At(cut_index + 1) - 1, &dummy, in_range_label,
|
|
&dummy);
|
|
ASSERT(!dummy.IsLinked());
|
|
// Cut out the single range by rewriting the array. This creates a new
|
|
// range that is a merger of the two ranges on either side of the one we
|
|
// are cutting out. The oddity of the labels is preserved.
|
|
for (intptr_t j = cut_index; j > start_index; j--) {
|
|
(*ranges)[j] = ranges->At(j - 1);
|
|
}
|
|
for (intptr_t j = cut_index + 1; j < end_index; j++) {
|
|
(*ranges)[j] = ranges->At(j + 1);
|
|
}
|
|
}
|
|
|
|
// Unicode case. Split the search space into kSize spaces that are handled
|
|
// with recursion.
|
|
static void SplitSearchSpace(ZoneGrowableArray<uint16_t>* ranges,
|
|
intptr_t start_index,
|
|
intptr_t end_index,
|
|
intptr_t* new_start_index,
|
|
intptr_t* new_end_index,
|
|
uint16_t* border) {
|
|
static const intptr_t kSize = RegExpMacroAssembler::kTableSize;
|
|
static const intptr_t kMask = RegExpMacroAssembler::kTableMask;
|
|
|
|
uint16_t first = ranges->At(start_index);
|
|
uint16_t last = ranges->At(end_index) - 1;
|
|
|
|
*new_start_index = start_index;
|
|
*border = (ranges->At(start_index) & ~kMask) + kSize;
|
|
while (*new_start_index < end_index) {
|
|
if (ranges->At(*new_start_index) > *border) break;
|
|
(*new_start_index)++;
|
|
}
|
|
// new_start_index is the index of the first edge that is beyond the
|
|
// current kSize space.
|
|
|
|
// For very large search spaces we do a binary chop search of the non-Latin1
|
|
// space instead of just going to the end of the current kSize space. The
|
|
// heuristics are complicated a little by the fact that any 128-character
|
|
// encoding space can be quickly tested with a table lookup, so we don't
|
|
// wish to do binary chop search at a smaller granularity than that. A
|
|
// 128-character space can take up a lot of space in the ranges array if,
|
|
// for example, we only want to match every second character (eg. the lower
|
|
// case characters on some Unicode pages).
|
|
intptr_t binary_chop_index = (end_index + start_index) / 2;
|
|
// The first test ensures that we get to the code that handles the Latin1
|
|
// range with a single not-taken branch, speeding up this important
|
|
// character range (even non-Latin1 charset-based text has spaces and
|
|
// punctuation).
|
|
if (*border - 1 > Symbols::kMaxOneCharCodeSymbol && // Latin1 case.
|
|
end_index - start_index > (*new_start_index - start_index) * 2 &&
|
|
last - first > kSize * 2 && binary_chop_index > *new_start_index &&
|
|
ranges->At(binary_chop_index) >= first + 2 * kSize) {
|
|
intptr_t scan_forward_for_section_border = binary_chop_index;
|
|
intptr_t new_border = (ranges->At(binary_chop_index) | kMask) + 1;
|
|
|
|
while (scan_forward_for_section_border < end_index) {
|
|
if (ranges->At(scan_forward_for_section_border) > new_border) {
|
|
*new_start_index = scan_forward_for_section_border;
|
|
*border = new_border;
|
|
break;
|
|
}
|
|
scan_forward_for_section_border++;
|
|
}
|
|
}
|
|
|
|
ASSERT(*new_start_index > start_index);
|
|
*new_end_index = *new_start_index - 1;
|
|
if (ranges->At(*new_end_index) == *border) {
|
|
(*new_end_index)--;
|
|
}
|
|
if (*border >= ranges->At(end_index)) {
|
|
*border = ranges->At(end_index);
|
|
*new_start_index = end_index; // Won't be used.
|
|
*new_end_index = end_index - 1;
|
|
}
|
|
}
|
|
|
|
// Gets a series of segment boundaries representing a character class. If the
|
|
// character is in the range between an even and an odd boundary (counting from
|
|
// start_index) then go to even_label, otherwise go to odd_label. We already
|
|
// know that the character is in the range of min_char to max_char inclusive.
|
|
// Either label can be NULL indicating backtracking. Either label can also be
|
|
// equal to the fall_through label.
|
|
static void GenerateBranches(RegExpMacroAssembler* masm,
|
|
ZoneGrowableArray<uint16_t>* ranges,
|
|
intptr_t start_index,
|
|
intptr_t end_index,
|
|
uint16_t min_char,
|
|
uint16_t max_char,
|
|
BlockLabel* fall_through,
|
|
BlockLabel* even_label,
|
|
BlockLabel* odd_label) {
|
|
uint16_t first = ranges->At(start_index);
|
|
uint16_t last = ranges->At(end_index) - 1;
|
|
|
|
ASSERT(min_char < first);
|
|
|
|
// Just need to test if the character is before or on-or-after
|
|
// a particular character.
|
|
if (start_index == end_index) {
|
|
EmitBoundaryTest(masm, first, fall_through, even_label, odd_label);
|
|
return;
|
|
}
|
|
|
|
// Another almost trivial case: There is one interval in the middle that is
|
|
// different from the end intervals.
|
|
if (start_index + 1 == end_index) {
|
|
EmitDoubleBoundaryTest(masm, first, last, fall_through, even_label,
|
|
odd_label);
|
|
return;
|
|
}
|
|
|
|
// It's not worth using table lookup if there are very few intervals in the
|
|
// character class.
|
|
if (end_index - start_index <= 6) {
|
|
// It is faster to test for individual characters, so we look for those
|
|
// first, then try arbitrary ranges in the second round.
|
|
static intptr_t kNoCutIndex = -1;
|
|
intptr_t cut = kNoCutIndex;
|
|
for (intptr_t i = start_index; i < end_index; i++) {
|
|
if (ranges->At(i) == ranges->At(i + 1) - 1) {
|
|
cut = i;
|
|
break;
|
|
}
|
|
}
|
|
if (cut == kNoCutIndex) cut = start_index;
|
|
CutOutRange(masm, ranges, start_index, end_index, cut, even_label,
|
|
odd_label);
|
|
ASSERT(end_index - start_index >= 2);
|
|
GenerateBranches(masm, ranges, start_index + 1, end_index - 1, min_char,
|
|
max_char, fall_through, even_label, odd_label);
|
|
return;
|
|
}
|
|
|
|
// If there are a lot of intervals in the regexp, then we will use tables to
|
|
// determine whether the character is inside or outside the character class.
|
|
static const intptr_t kBits = RegExpMacroAssembler::kTableSizeBits;
|
|
|
|
if ((max_char >> kBits) == (min_char >> kBits)) {
|
|
EmitUseLookupTable(masm, ranges, start_index, end_index, min_char,
|
|
fall_through, even_label, odd_label);
|
|
return;
|
|
}
|
|
|
|
if ((min_char >> kBits) != (first >> kBits)) {
|
|
masm->CheckCharacterLT(first, odd_label);
|
|
GenerateBranches(masm, ranges, start_index + 1, end_index, first, max_char,
|
|
fall_through, odd_label, even_label);
|
|
return;
|
|
}
|
|
|
|
intptr_t new_start_index = 0;
|
|
intptr_t new_end_index = 0;
|
|
uint16_t border = 0;
|
|
|
|
SplitSearchSpace(ranges, start_index, end_index, &new_start_index,
|
|
&new_end_index, &border);
|
|
|
|
BlockLabel handle_rest;
|
|
BlockLabel* above = &handle_rest;
|
|
if (border == last + 1) {
|
|
// We didn't find any section that started after the limit, so everything
|
|
// above the border is one of the terminal labels.
|
|
above = (end_index & 1) != (start_index & 1) ? odd_label : even_label;
|
|
ASSERT(new_end_index == end_index - 1);
|
|
}
|
|
|
|
ASSERT(start_index <= new_end_index);
|
|
ASSERT(new_start_index <= end_index);
|
|
ASSERT(start_index < new_start_index);
|
|
ASSERT(new_end_index < end_index);
|
|
ASSERT(new_end_index + 1 == new_start_index ||
|
|
(new_end_index + 2 == new_start_index &&
|
|
border == ranges->At(new_end_index + 1)));
|
|
ASSERT(min_char < border - 1);
|
|
ASSERT(border < max_char);
|
|
ASSERT(ranges->At(new_end_index) < border);
|
|
ASSERT(border < ranges->At(new_start_index) ||
|
|
(border == ranges->At(new_start_index) &&
|
|
new_start_index == end_index && new_end_index == end_index - 1 &&
|
|
border == last + 1));
|
|
ASSERT(new_start_index == 0 || border >= ranges->At(new_start_index - 1));
|
|
|
|
masm->CheckCharacterGT(border - 1, above);
|
|
BlockLabel dummy;
|
|
GenerateBranches(masm, ranges, start_index, new_end_index, min_char,
|
|
border - 1, &dummy, even_label, odd_label);
|
|
|
|
if (handle_rest.IsLinked()) {
|
|
masm->BindBlock(&handle_rest);
|
|
bool flip = (new_start_index & 1) != (start_index & 1);
|
|
GenerateBranches(masm, ranges, new_start_index, end_index, border, max_char,
|
|
&dummy, flip ? odd_label : even_label,
|
|
flip ? even_label : odd_label);
|
|
}
|
|
}
|
|
|
|
static void EmitCharClass(RegExpMacroAssembler* macro_assembler,
|
|
RegExpCharacterClass* cc,
|
|
bool one_byte,
|
|
BlockLabel* on_failure,
|
|
intptr_t cp_offset,
|
|
bool check_offset,
|
|
bool preloaded,
|
|
Zone* zone) {
|
|
ZoneGrowableArray<CharacterRange>* ranges = cc->ranges();
|
|
if (!CharacterRange::IsCanonical(ranges)) {
|
|
CharacterRange::Canonicalize(ranges);
|
|
}
|
|
|
|
uint16_t max_char;
|
|
if (one_byte) {
|
|
max_char = Symbols::kMaxOneCharCodeSymbol;
|
|
} else {
|
|
max_char = Utf16::kMaxCodeUnit;
|
|
}
|
|
|
|
intptr_t range_count = ranges->length();
|
|
|
|
intptr_t last_valid_range = range_count - 1;
|
|
while (last_valid_range >= 0) {
|
|
const CharacterRange& range = ranges->At(last_valid_range);
|
|
if (range.from() <= max_char) {
|
|
break;
|
|
}
|
|
last_valid_range--;
|
|
}
|
|
|
|
if (last_valid_range < 0) {
|
|
if (!cc->is_negated()) {
|
|
macro_assembler->GoTo(on_failure);
|
|
}
|
|
if (check_offset) {
|
|
macro_assembler->CheckPosition(cp_offset, on_failure);
|
|
}
|
|
return;
|
|
}
|
|
|
|
if (last_valid_range == 0 && ranges->At(0).IsEverything(max_char)) {
|
|
if (cc->is_negated()) {
|
|
macro_assembler->GoTo(on_failure);
|
|
} else {
|
|
// This is a common case hit by non-anchored expressions.
|
|
if (check_offset) {
|
|
macro_assembler->CheckPosition(cp_offset, on_failure);
|
|
}
|
|
}
|
|
return;
|
|
}
|
|
|
|
if (!preloaded) {
|
|
macro_assembler->LoadCurrentCharacter(cp_offset, on_failure, check_offset);
|
|
}
|
|
|
|
if (cc->is_standard() && macro_assembler->CheckSpecialCharacterClass(
|
|
cc->standard_type(), on_failure)) {
|
|
return;
|
|
}
|
|
|
|
// A new list with ascending entries. Each entry is a code unit
|
|
// where there is a boundary between code units that are part of
|
|
// the class and code units that are not. Normally we insert an
|
|
// entry at zero which goes to the failure label, but if there
|
|
// was already one there we fall through for success on that entry.
|
|
// Subsequent entries have alternating meaning (success/failure).
|
|
ZoneGrowableArray<uint16_t>* range_boundaries =
|
|
new (zone) ZoneGrowableArray<uint16_t>(last_valid_range);
|
|
|
|
bool zeroth_entry_is_failure = !cc->is_negated();
|
|
|
|
for (intptr_t i = 0; i <= last_valid_range; i++) {
|
|
const CharacterRange& range = ranges->At(i);
|
|
if (range.from() == 0) {
|
|
ASSERT(i == 0);
|
|
zeroth_entry_is_failure = !zeroth_entry_is_failure;
|
|
} else {
|
|
range_boundaries->Add(range.from());
|
|
}
|
|
if (range.to() + 1 <= max_char) {
|
|
range_boundaries->Add(range.to() + 1);
|
|
}
|
|
}
|
|
intptr_t end_index = range_boundaries->length() - 1;
|
|
|
|
BlockLabel fall_through;
|
|
GenerateBranches(macro_assembler, range_boundaries,
|
|
0, // start_index.
|
|
end_index,
|
|
0, // min_char.
|
|
max_char, &fall_through,
|
|
zeroth_entry_is_failure ? &fall_through : on_failure,
|
|
zeroth_entry_is_failure ? on_failure : &fall_through);
|
|
macro_assembler->BindBlock(&fall_through);
|
|
}
|
|
|
|
RegExpNode::~RegExpNode() {}
|
|
|
|
RegExpNode::LimitResult RegExpNode::LimitVersions(RegExpCompiler* compiler,
|
|
Trace* trace) {
|
|
// If we are generating a greedy loop then don't stop and don't reuse code.
|
|
if (trace->stop_node() != NULL) {
|
|
return CONTINUE;
|
|
}
|
|
|
|
RegExpMacroAssembler* macro_assembler = compiler->macro_assembler();
|
|
if (trace->is_trivial()) {
|
|
if (label_.IsBound()) {
|
|
// We are being asked to generate a generic version, but that's already
|
|
// been done so just go to it.
|
|
macro_assembler->GoTo(&label_);
|
|
return DONE;
|
|
}
|
|
if (compiler->recursion_depth() >= RegExpCompiler::kMaxRecursion) {
|
|
// To avoid too deep recursion we push the node to the work queue and just
|
|
// generate a goto here.
|
|
compiler->AddWork(this);
|
|
macro_assembler->GoTo(&label_);
|
|
return DONE;
|
|
}
|
|
// Generate generic version of the node and bind the label for later use.
|
|
macro_assembler->BindBlock(&label_);
|
|
return CONTINUE;
|
|
}
|
|
|
|
// We are being asked to make a non-generic version. Keep track of how many
|
|
// non-generic versions we generate so as not to overdo it.
|
|
trace_count_++;
|
|
if (kRegexpOptimization && trace_count_ < kMaxCopiesCodeGenerated &&
|
|
compiler->recursion_depth() <= RegExpCompiler::kMaxRecursion) {
|
|
return CONTINUE;
|
|
}
|
|
|
|
// If we get here code has been generated for this node too many times or
|
|
// recursion is too deep. Time to switch to a generic version. The code for
|
|
// generic versions above can handle deep recursion properly.
|
|
trace->Flush(compiler, this);
|
|
return DONE;
|
|
}
|
|
|
|
intptr_t ActionNode::EatsAtLeast(intptr_t still_to_find,
|
|
intptr_t budget,
|
|
bool not_at_start) {
|
|
if (budget <= 0) return 0;
|
|
if (action_type_ == POSITIVE_SUBMATCH_SUCCESS) return 0; // Rewinds input!
|
|
return on_success()->EatsAtLeast(still_to_find, budget - 1, not_at_start);
|
|
}
|
|
|
|
void ActionNode::FillInBMInfo(intptr_t offset,
|
|
intptr_t budget,
|
|
BoyerMooreLookahead* bm,
|
|
bool not_at_start) {
|
|
if (action_type_ == BEGIN_SUBMATCH) {
|
|
bm->SetRest(offset);
|
|
} else if (action_type_ != POSITIVE_SUBMATCH_SUCCESS) {
|
|
on_success()->FillInBMInfo(offset, budget - 1, bm, not_at_start);
|
|
}
|
|
SaveBMInfo(bm, not_at_start, offset);
|
|
}
|
|
|
|
intptr_t AssertionNode::EatsAtLeast(intptr_t still_to_find,
|
|
intptr_t budget,
|
|
bool not_at_start) {
|
|
if (budget <= 0) return 0;
|
|
// If we know we are not at the start and we are asked "how many characters
|
|
// will you match if you succeed?" then we can answer anything since false
|
|
// implies false. So lets just return the max answer (still_to_find) since
|
|
// that won't prevent us from preloading a lot of characters for the other
|
|
// branches in the node graph.
|
|
if (assertion_type() == AT_START && not_at_start) return still_to_find;
|
|
return on_success()->EatsAtLeast(still_to_find, budget - 1, not_at_start);
|
|
}
|
|
|
|
void AssertionNode::FillInBMInfo(intptr_t offset,
|
|
intptr_t budget,
|
|
BoyerMooreLookahead* bm,
|
|
bool not_at_start) {
|
|
// Match the behaviour of EatsAtLeast on this node.
|
|
if (assertion_type() == AT_START && not_at_start) return;
|
|
on_success()->FillInBMInfo(offset, budget - 1, bm, not_at_start);
|
|
SaveBMInfo(bm, not_at_start, offset);
|
|
}
|
|
|
|
intptr_t BackReferenceNode::EatsAtLeast(intptr_t still_to_find,
|
|
intptr_t budget,
|
|
bool not_at_start) {
|
|
if (read_backward()) return 0;
|
|
if (budget <= 0) return 0;
|
|
return on_success()->EatsAtLeast(still_to_find, budget - 1, not_at_start);
|
|
}
|
|
|
|
intptr_t TextNode::EatsAtLeast(intptr_t still_to_find,
|
|
intptr_t budget,
|
|
bool not_at_start) {
|
|
if (read_backward()) return 0;
|
|
intptr_t answer = Length();
|
|
if (answer >= still_to_find) return answer;
|
|
if (budget <= 0) return answer;
|
|
// We are not at start after this node so we set the last argument to 'true'.
|
|
return answer +
|
|
on_success()->EatsAtLeast(still_to_find - answer, budget - 1, true);
|
|
}
|
|
|
|
intptr_t NegativeLookaroundChoiceNode::EatsAtLeast(intptr_t still_to_find,
|
|
intptr_t budget,
|
|
bool not_at_start) {
|
|
if (budget <= 0) return 0;
|
|
// Alternative 0 is the negative lookahead, alternative 1 is what comes
|
|
// afterwards.
|
|
RegExpNode* node = (*alternatives_)[1].node();
|
|
return node->EatsAtLeast(still_to_find, budget - 1, not_at_start);
|
|
}
|
|
|
|
void NegativeLookaroundChoiceNode::GetQuickCheckDetails(
|
|
QuickCheckDetails* details,
|
|
RegExpCompiler* compiler,
|
|
intptr_t filled_in,
|
|
bool not_at_start) {
|
|
// Alternative 0 is the negative lookahead, alternative 1 is what comes
|
|
// afterwards.
|
|
RegExpNode* node = (*alternatives_)[1].node();
|
|
return node->GetQuickCheckDetails(details, compiler, filled_in, not_at_start);
|
|
}
|
|
|
|
intptr_t ChoiceNode::EatsAtLeastHelper(intptr_t still_to_find,
|
|
intptr_t budget,
|
|
RegExpNode* ignore_this_node,
|
|
bool not_at_start) {
|
|
if (budget <= 0) return 0;
|
|
intptr_t min = 100;
|
|
intptr_t choice_count = alternatives_->length();
|
|
budget = (budget - 1) / choice_count;
|
|
for (intptr_t i = 0; i < choice_count; i++) {
|
|
RegExpNode* node = (*alternatives_)[i].node();
|
|
if (node == ignore_this_node) continue;
|
|
intptr_t node_eats_at_least =
|
|
node->EatsAtLeast(still_to_find, budget, not_at_start);
|
|
if (node_eats_at_least < min) min = node_eats_at_least;
|
|
if (min == 0) return 0;
|
|
}
|
|
return min;
|
|
}
|
|
|
|
intptr_t LoopChoiceNode::EatsAtLeast(intptr_t still_to_find,
|
|
intptr_t budget,
|
|
bool not_at_start) {
|
|
return EatsAtLeastHelper(still_to_find, budget - 1, loop_node_, not_at_start);
|
|
}
|
|
|
|
intptr_t ChoiceNode::EatsAtLeast(intptr_t still_to_find,
|
|
intptr_t budget,
|
|
bool not_at_start) {
|
|
return EatsAtLeastHelper(still_to_find, budget, NULL, not_at_start);
|
|
}
|
|
|
|
// Takes the left-most 1-bit and smears it out, setting all bits to its right.
|
|
static inline uint32_t SmearBitsRight(uint32_t v) {
|
|
v |= v >> 1;
|
|
v |= v >> 2;
|
|
v |= v >> 4;
|
|
v |= v >> 8;
|
|
v |= v >> 16;
|
|
return v;
|
|
}
|
|
|
|
bool QuickCheckDetails::Rationalize(bool asc) {
|
|
bool found_useful_op = false;
|
|
uint32_t char_mask;
|
|
if (asc) {
|
|
char_mask = Symbols::kMaxOneCharCodeSymbol;
|
|
} else {
|
|
char_mask = Utf16::kMaxCodeUnit;
|
|
}
|
|
mask_ = 0;
|
|
value_ = 0;
|
|
intptr_t char_shift = 0;
|
|
for (intptr_t i = 0; i < characters_; i++) {
|
|
Position* pos = &positions_[i];
|
|
if ((pos->mask & Symbols::kMaxOneCharCodeSymbol) != 0) {
|
|
found_useful_op = true;
|
|
}
|
|
mask_ |= (pos->mask & char_mask) << char_shift;
|
|
value_ |= (pos->value & char_mask) << char_shift;
|
|
char_shift += asc ? 8 : 16;
|
|
}
|
|
return found_useful_op;
|
|
}
|
|
|
|
bool RegExpNode::EmitQuickCheck(RegExpCompiler* compiler,
|
|
Trace* bounds_check_trace,
|
|
Trace* trace,
|
|
bool preload_has_checked_bounds,
|
|
BlockLabel* on_possible_success,
|
|
QuickCheckDetails* details,
|
|
bool fall_through_on_failure) {
|
|
if (details->characters() == 0) return false;
|
|
GetQuickCheckDetails(details, compiler, 0,
|
|
trace->at_start() == Trace::FALSE_VALUE);
|
|
if (details->cannot_match()) return false;
|
|
if (!details->Rationalize(compiler->one_byte())) return false;
|
|
ASSERT(details->characters() == 1 ||
|
|
compiler->macro_assembler()->CanReadUnaligned());
|
|
uint32_t mask = details->mask();
|
|
uint32_t value = details->value();
|
|
|
|
RegExpMacroAssembler* assembler = compiler->macro_assembler();
|
|
|
|
if (trace->characters_preloaded() != details->characters()) {
|
|
ASSERT(trace->cp_offset() == bounds_check_trace->cp_offset());
|
|
// We are attempting to preload the minimum number of characters
|
|
// any choice would eat, so if the bounds check fails, then none of the
|
|
// choices can succeed, so we can just immediately backtrack, rather
|
|
// than go to the next choice.
|
|
assembler->LoadCurrentCharacter(
|
|
trace->cp_offset(), bounds_check_trace->backtrack(),
|
|
!preload_has_checked_bounds, details->characters());
|
|
}
|
|
|
|
bool need_mask = true;
|
|
|
|
if (details->characters() == 1) {
|
|
// If number of characters preloaded is 1 then we used a byte or 16 bit
|
|
// load so the value is already masked down.
|
|
uint32_t char_mask;
|
|
if (compiler->one_byte()) {
|
|
char_mask = Symbols::kMaxOneCharCodeSymbol;
|
|
} else {
|
|
char_mask = Utf16::kMaxCodeUnit;
|
|
}
|
|
if ((mask & char_mask) == char_mask) need_mask = false;
|
|
mask &= char_mask;
|
|
} else {
|
|
// For 2-character preloads in one-byte mode or 1-character preloads in
|
|
// two-byte mode we also use a 16 bit load with zero extend.
|
|
if (details->characters() == 2 && compiler->one_byte()) {
|
|
if ((mask & 0xffff) == 0xffff) need_mask = false;
|
|
} else if (details->characters() == 1 && !compiler->one_byte()) {
|
|
if ((mask & 0xffff) == 0xffff) need_mask = false;
|
|
} else {
|
|
if (mask == 0xffffffff) need_mask = false;
|
|
}
|
|
}
|
|
|
|
if (fall_through_on_failure) {
|
|
if (need_mask) {
|
|
assembler->CheckCharacterAfterAnd(value, mask, on_possible_success);
|
|
} else {
|
|
assembler->CheckCharacter(value, on_possible_success);
|
|
}
|
|
} else {
|
|
if (need_mask) {
|
|
assembler->CheckNotCharacterAfterAnd(value, mask, trace->backtrack());
|
|
} else {
|
|
assembler->CheckNotCharacter(value, trace->backtrack());
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
// Here is the meat of GetQuickCheckDetails (see also the comment on the
|
|
// super-class in the .h file).
|
|
//
|
|
// We iterate along the text object, building up for each character a
|
|
// mask and value that can be used to test for a quick failure to match.
|
|
// The masks and values for the positions will be combined into a single
|
|
// machine word for the current character width in order to be used in
|
|
// generating a quick check.
|
|
void TextNode::GetQuickCheckDetails(QuickCheckDetails* details,
|
|
RegExpCompiler* compiler,
|
|
intptr_t characters_filled_in,
|
|
bool not_at_start) {
|
|
#if defined(__GNUC__) && defined(__BYTE_ORDER__)
|
|
// TODO(zerny): Make the combination code byte-order independent.
|
|
ASSERT(details->characters() == 1 ||
|
|
(__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__));
|
|
#endif
|
|
// Do not collect any quick check details if the text node reads backward,
|
|
// since it reads in the opposite direction than we use for quick checks.
|
|
if (read_backward()) return;
|
|
ASSERT(characters_filled_in < details->characters());
|
|
intptr_t characters = details->characters();
|
|
int32_t char_mask;
|
|
if (compiler->one_byte()) {
|
|
char_mask = Symbols::kMaxOneCharCodeSymbol;
|
|
} else {
|
|
char_mask = Utf16::kMaxCodeUnit;
|
|
}
|
|
for (intptr_t k = 0; k < elms_->length(); k++) {
|
|
TextElement elm = elms_->At(k);
|
|
if (elm.text_type() == TextElement::ATOM) {
|
|
ZoneGrowableArray<uint16_t>* quarks = elm.atom()->data();
|
|
for (intptr_t i = 0; i < characters && i < quarks->length(); i++) {
|
|
QuickCheckDetails::Position* pos =
|
|
details->positions(characters_filled_in);
|
|
uint16_t c = quarks->At(i);
|
|
if (c > char_mask) {
|
|
// If we expect a non-Latin1 character from an one-byte string,
|
|
// there is no way we can match. Not even case independent
|
|
// matching can turn an Latin1 character into non-Latin1 or
|
|
// vice versa.
|
|
// TODO(dcarney): issue 3550. Verify that this works as expected.
|
|
// For example, \u0178 is uppercase of \u00ff (y-umlaut).
|
|
details->set_cannot_match();
|
|
pos->determines_perfectly = false;
|
|
return;
|
|
}
|
|
if (elm.atom()->ignore_case()) {
|
|
int32_t chars[unibrow::Ecma262UnCanonicalize::kMaxWidth];
|
|
intptr_t length =
|
|
GetCaseIndependentLetters(c, compiler->one_byte(), chars);
|
|
ASSERT(length != 0); // Can only happen if c > char_mask (see above).
|
|
if (length == 1) {
|
|
// This letter has no case equivalents, so it's nice and simple
|
|
// and the mask-compare will determine definitely whether we have
|
|
// a match at this character position.
|
|
pos->mask = char_mask;
|
|
pos->value = c;
|
|
pos->determines_perfectly = true;
|
|
} else {
|
|
uint32_t common_bits = char_mask;
|
|
uint32_t bits = chars[0];
|
|
for (intptr_t j = 1; j < length; j++) {
|
|
uint32_t differing_bits = ((chars[j] & common_bits) ^ bits);
|
|
common_bits ^= differing_bits;
|
|
bits &= common_bits;
|
|
}
|
|
// If length is 2 and common bits has only one zero in it then
|
|
// our mask and compare instruction will determine definitely
|
|
// whether we have a match at this character position. Otherwise
|
|
// it can only be an approximate check.
|
|
uint32_t one_zero = (common_bits | ~char_mask);
|
|
if (length == 2 && ((~one_zero) & ((~one_zero) - 1)) == 0) {
|
|
pos->determines_perfectly = true;
|
|
}
|
|
pos->mask = common_bits;
|
|
pos->value = bits;
|
|
}
|
|
} else {
|
|
// Don't ignore case. Nice simple case where the mask-compare will
|
|
// determine definitely whether we have a match at this character
|
|
// position.
|
|
pos->mask = char_mask;
|
|
pos->value = c;
|
|
pos->determines_perfectly = true;
|
|
}
|
|
characters_filled_in++;
|
|
ASSERT(characters_filled_in <= details->characters());
|
|
if (characters_filled_in == details->characters()) {
|
|
return;
|
|
}
|
|
}
|
|
} else {
|
|
QuickCheckDetails::Position* pos =
|
|
details->positions(characters_filled_in);
|
|
RegExpCharacterClass* tree = elm.char_class();
|
|
ZoneGrowableArray<CharacterRange>* ranges = tree->ranges();
|
|
ASSERT(!ranges->is_empty());
|
|
if (tree->is_negated()) {
|
|
// A quick check uses multi-character mask and compare. There is no
|
|
// useful way to incorporate a negative char class into this scheme
|
|
// so we just conservatively create a mask and value that will always
|
|
// succeed.
|
|
pos->mask = 0;
|
|
pos->value = 0;
|
|
} else {
|
|
intptr_t first_range = 0;
|
|
while (ranges->At(first_range).from() > char_mask) {
|
|
first_range++;
|
|
if (first_range == ranges->length()) {
|
|
details->set_cannot_match();
|
|
pos->determines_perfectly = false;
|
|
return;
|
|
}
|
|
}
|
|
CharacterRange range = ranges->At(first_range);
|
|
uint16_t from = range.from();
|
|
uint16_t to = range.to();
|
|
if (to > char_mask) {
|
|
to = char_mask;
|
|
}
|
|
uint32_t differing_bits = (from ^ to);
|
|
// A mask and compare is only perfect if the differing bits form a
|
|
// number like 00011111 with one single block of trailing 1s.
|
|
if ((differing_bits & (differing_bits + 1)) == 0 &&
|
|
from + differing_bits == to) {
|
|
pos->determines_perfectly = true;
|
|
}
|
|
uint32_t common_bits = ~SmearBitsRight(differing_bits);
|
|
uint32_t bits = (from & common_bits);
|
|
for (intptr_t i = first_range + 1; i < ranges->length(); i++) {
|
|
CharacterRange range = ranges->At(i);
|
|
uint16_t from = range.from();
|
|
uint16_t to = range.to();
|
|
if (from > char_mask) continue;
|
|
if (to > char_mask) to = char_mask;
|
|
// Here we are combining more ranges into the mask and compare
|
|
// value. With each new range the mask becomes more sparse and
|
|
// so the chances of a false positive rise. A character class
|
|
// with multiple ranges is assumed never to be equivalent to a
|
|
// mask and compare operation.
|
|
pos->determines_perfectly = false;
|
|
uint32_t new_common_bits = (from ^ to);
|
|
new_common_bits = ~SmearBitsRight(new_common_bits);
|
|
common_bits &= new_common_bits;
|
|
bits &= new_common_bits;
|
|
uint32_t differing_bits = (from & common_bits) ^ bits;
|
|
common_bits ^= differing_bits;
|
|
bits &= common_bits;
|
|
}
|
|
pos->mask = common_bits;
|
|
pos->value = bits;
|
|
}
|
|
characters_filled_in++;
|
|
ASSERT(characters_filled_in <= details->characters());
|
|
if (characters_filled_in == details->characters()) {
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
ASSERT(characters_filled_in != details->characters());
|
|
if (!details->cannot_match()) {
|
|
on_success()->GetQuickCheckDetails(details, compiler, characters_filled_in,
|
|
true);
|
|
}
|
|
}
|
|
|
|
void QuickCheckDetails::Clear() {
|
|
for (int i = 0; i < characters_; i++) {
|
|
positions_[i].mask = 0;
|
|
positions_[i].value = 0;
|
|
positions_[i].determines_perfectly = false;
|
|
}
|
|
characters_ = 0;
|
|
}
|
|
|
|
void QuickCheckDetails::Advance(intptr_t by, bool one_byte) {
|
|
if (by >= characters_ || by < 0) {
|
|
// check that by < 0 => characters_ == 0
|
|
ASSERT(by >= 0 || characters_ == 0);
|
|
Clear();
|
|
return;
|
|
}
|
|
for (intptr_t i = 0; i < characters_ - by; i++) {
|
|
positions_[i] = positions_[by + i];
|
|
}
|
|
for (intptr_t i = characters_ - by; i < characters_; i++) {
|
|
positions_[i].mask = 0;
|
|
positions_[i].value = 0;
|
|
positions_[i].determines_perfectly = false;
|
|
}
|
|
characters_ -= by;
|
|
// We could change mask_ and value_ here but we would never advance unless
|
|
// they had already been used in a check and they won't be used again because
|
|
// it would gain us nothing. So there's no point.
|
|
}
|
|
|
|
void QuickCheckDetails::Merge(QuickCheckDetails* other, intptr_t from_index) {
|
|
ASSERT(characters_ == other->characters_);
|
|
if (other->cannot_match_) {
|
|
return;
|
|
}
|
|
if (cannot_match_) {
|
|
*this = *other;
|
|
return;
|
|
}
|
|
for (intptr_t i = from_index; i < characters_; i++) {
|
|
QuickCheckDetails::Position* pos = positions(i);
|
|
QuickCheckDetails::Position* other_pos = other->positions(i);
|
|
if (pos->mask != other_pos->mask || pos->value != other_pos->value ||
|
|
!other_pos->determines_perfectly) {
|
|
// Our mask-compare operation will be approximate unless we have the
|
|
// exact same operation on both sides of the alternation.
|
|
pos->determines_perfectly = false;
|
|
}
|
|
pos->mask &= other_pos->mask;
|
|
pos->value &= pos->mask;
|
|
other_pos->value &= pos->mask;
|
|
uint16_t differing_bits = (pos->value ^ other_pos->value);
|
|
pos->mask &= ~differing_bits;
|
|
pos->value &= pos->mask;
|
|
}
|
|
}
|
|
|
|
class VisitMarker : public ValueObject {
|
|
public:
|
|
explicit VisitMarker(NodeInfo* info) : info_(info) {
|
|
ASSERT(!info->visited);
|
|
info->visited = true;
|
|
}
|
|
~VisitMarker() { info_->visited = false; }
|
|
|
|
private:
|
|
NodeInfo* info_;
|
|
};
|
|
|
|
RegExpNode* SeqRegExpNode::FilterOneByte(intptr_t depth) {
|
|
if (info()->replacement_calculated) return replacement();
|
|
if (depth < 0) return this;
|
|
ASSERT(!info()->visited);
|
|
VisitMarker marker(info());
|
|
return FilterSuccessor(depth - 1);
|
|
}
|
|
|
|
RegExpNode* SeqRegExpNode::FilterSuccessor(intptr_t depth) {
|
|
RegExpNode* next = on_success_->FilterOneByte(depth - 1);
|
|
if (next == NULL) return set_replacement(NULL);
|
|
on_success_ = next;
|
|
return set_replacement(this);
|
|
}
|
|
|
|
// We need to check for the following characters: 0x39c 0x3bc 0x178.
|
|
static inline bool RangeContainsLatin1Equivalents(CharacterRange range) {
|
|
// TODO(dcarney): this could be a lot more efficient.
|
|
return range.Contains(0x39c) || range.Contains(0x3bc) ||
|
|
range.Contains(0x178);
|
|
}
|
|
|
|
static bool RangesContainLatin1Equivalents(
|
|
ZoneGrowableArray<CharacterRange>* ranges) {
|
|
for (intptr_t i = 0; i < ranges->length(); i++) {
|
|
// TODO(dcarney): this could be a lot more efficient.
|
|
if (RangeContainsLatin1Equivalents(ranges->At(i))) return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
static uint16_t ConvertNonLatin1ToLatin1(uint16_t c) {
|
|
ASSERT(c > Symbols::kMaxOneCharCodeSymbol);
|
|
switch (c) {
|
|
// This are equivalent characters in unicode.
|
|
case 0x39c:
|
|
case 0x3bc:
|
|
return 0xb5;
|
|
// This is an uppercase of a Latin-1 character
|
|
// outside of Latin-1.
|
|
case 0x178:
|
|
return 0xff;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
RegExpNode* TextNode::FilterOneByte(intptr_t depth) {
|
|
if (info()->replacement_calculated) return replacement();
|
|
if (depth < 0) return this;
|
|
ASSERT(!info()->visited);
|
|
VisitMarker marker(info());
|
|
intptr_t element_count = elms_->length();
|
|
for (intptr_t i = 0; i < element_count; i++) {
|
|
TextElement elm = elms_->At(i);
|
|
if (elm.text_type() == TextElement::ATOM) {
|
|
ZoneGrowableArray<uint16_t>* quarks = elm.atom()->data();
|
|
for (intptr_t j = 0; j < quarks->length(); j++) {
|
|
uint16_t c = quarks->At(j);
|
|
if (c <= Symbols::kMaxOneCharCodeSymbol) continue;
|
|
if (!elm.atom()->ignore_case()) return set_replacement(NULL);
|
|
// Here, we need to check for characters whose upper and lower cases
|
|
// are outside the Latin-1 range.
|
|
uint16_t converted = ConvertNonLatin1ToLatin1(c);
|
|
// Character is outside Latin-1 completely
|
|
if (converted == 0) return set_replacement(NULL);
|
|
// Convert quark to Latin-1 in place.
|
|
(*quarks)[0] = converted;
|
|
}
|
|
} else {
|
|
ASSERT(elm.text_type() == TextElement::CHAR_CLASS);
|
|
RegExpCharacterClass* cc = elm.char_class();
|
|
ZoneGrowableArray<CharacterRange>* ranges = cc->ranges();
|
|
if (!CharacterRange::IsCanonical(ranges)) {
|
|
CharacterRange::Canonicalize(ranges);
|
|
}
|
|
// Now they are in order so we only need to look at the first.
|
|
intptr_t range_count = ranges->length();
|
|
if (cc->is_negated()) {
|
|
if (range_count != 0 && ranges->At(0).from() == 0 &&
|
|
ranges->At(0).to() >= Symbols::kMaxOneCharCodeSymbol) {
|
|
// This will be handled in a later filter.
|
|
if (cc->flags().IgnoreCase() &&
|
|
RangesContainLatin1Equivalents(ranges)) {
|
|
continue;
|
|
}
|
|
return set_replacement(NULL);
|
|
}
|
|
} else {
|
|
if (range_count == 0 ||
|
|
ranges->At(0).from() > Symbols::kMaxOneCharCodeSymbol) {
|
|
// This will be handled in a later filter.
|
|
if (cc->flags().IgnoreCase() &&
|
|
RangesContainLatin1Equivalents(ranges))
|
|
continue;
|
|
return set_replacement(NULL);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return FilterSuccessor(depth - 1);
|
|
}
|
|
|
|
RegExpNode* LoopChoiceNode::FilterOneByte(intptr_t depth) {
|
|
if (info()->replacement_calculated) return replacement();
|
|
if (depth < 0) return this;
|
|
if (info()->visited) return this;
|
|
{
|
|
VisitMarker marker(info());
|
|
|
|
RegExpNode* continue_replacement = continue_node_->FilterOneByte(depth - 1);
|
|
// If we can't continue after the loop then there is no sense in doing the
|
|
// loop.
|
|
if (continue_replacement == NULL) return set_replacement(NULL);
|
|
}
|
|
|
|
return ChoiceNode::FilterOneByte(depth - 1);
|
|
}
|
|
|
|
RegExpNode* ChoiceNode::FilterOneByte(intptr_t depth) {
|
|
if (info()->replacement_calculated) return replacement();
|
|
if (depth < 0) return this;
|
|
if (info()->visited) return this;
|
|
VisitMarker marker(info());
|
|
intptr_t choice_count = alternatives_->length();
|
|
|
|
for (intptr_t i = 0; i < choice_count; i++) {
|
|
GuardedAlternative alternative = alternatives_->At(i);
|
|
if (alternative.guards() != NULL && alternative.guards()->length() != 0) {
|
|
set_replacement(this);
|
|
return this;
|
|
}
|
|
}
|
|
|
|
intptr_t surviving = 0;
|
|
RegExpNode* survivor = NULL;
|
|
for (intptr_t i = 0; i < choice_count; i++) {
|
|
GuardedAlternative alternative = alternatives_->At(i);
|
|
RegExpNode* replacement = alternative.node()->FilterOneByte(depth - 1);
|
|
ASSERT(replacement != this); // No missing EMPTY_MATCH_CHECK.
|
|
if (replacement != NULL) {
|
|
(*alternatives_)[i].set_node(replacement);
|
|
surviving++;
|
|
survivor = replacement;
|
|
}
|
|
}
|
|
if (surviving < 2) return set_replacement(survivor);
|
|
|
|
set_replacement(this);
|
|
if (surviving == choice_count) {
|
|
return this;
|
|
}
|
|
// Only some of the nodes survived the filtering. We need to rebuild the
|
|
// alternatives list.
|
|
ZoneGrowableArray<GuardedAlternative>* new_alternatives =
|
|
new (Z) ZoneGrowableArray<GuardedAlternative>(surviving);
|
|
for (intptr_t i = 0; i < choice_count; i++) {
|
|
RegExpNode* replacement =
|
|
(*alternatives_)[i].node()->FilterOneByte(depth - 1);
|
|
if (replacement != NULL) {
|
|
(*alternatives_)[i].set_node(replacement);
|
|
new_alternatives->Add((*alternatives_)[i]);
|
|
}
|
|
}
|
|
alternatives_ = new_alternatives;
|
|
return this;
|
|
}
|
|
|
|
RegExpNode* NegativeLookaroundChoiceNode::FilterOneByte(intptr_t depth) {
|
|
if (info()->replacement_calculated) return replacement();
|
|
if (depth < 0) return this;
|
|
if (info()->visited) return this;
|
|
VisitMarker marker(info());
|
|
// Alternative 0 is the negative lookahead, alternative 1 is what comes
|
|
// afterwards.
|
|
RegExpNode* node = (*alternatives_)[1].node();
|
|
RegExpNode* replacement = node->FilterOneByte(depth - 1);
|
|
if (replacement == NULL) return set_replacement(NULL);
|
|
(*alternatives_)[1].set_node(replacement);
|
|
|
|
RegExpNode* neg_node = (*alternatives_)[0].node();
|
|
RegExpNode* neg_replacement = neg_node->FilterOneByte(depth - 1);
|
|
// If the negative lookahead is always going to fail then
|
|
// we don't need to check it.
|
|
if (neg_replacement == NULL) return set_replacement(replacement);
|
|
(*alternatives_)[0].set_node(neg_replacement);
|
|
return set_replacement(this);
|
|
}
|
|
|
|
void LoopChoiceNode::GetQuickCheckDetails(QuickCheckDetails* details,
|
|
RegExpCompiler* compiler,
|
|
intptr_t characters_filled_in,
|
|
bool not_at_start) {
|
|
if (body_can_be_zero_length_ || info()->visited) return;
|
|
VisitMarker marker(info());
|
|
return ChoiceNode::GetQuickCheckDetails(details, compiler,
|
|
characters_filled_in, not_at_start);
|
|
}
|
|
|
|
void LoopChoiceNode::FillInBMInfo(intptr_t offset,
|
|
intptr_t budget,
|
|
BoyerMooreLookahead* bm,
|
|
bool not_at_start) {
|
|
if (body_can_be_zero_length_ || budget <= 0) {
|
|
bm->SetRest(offset);
|
|
SaveBMInfo(bm, not_at_start, offset);
|
|
return;
|
|
}
|
|
ChoiceNode::FillInBMInfo(offset, budget - 1, bm, not_at_start);
|
|
SaveBMInfo(bm, not_at_start, offset);
|
|
}
|
|
|
|
void ChoiceNode::GetQuickCheckDetails(QuickCheckDetails* details,
|
|
RegExpCompiler* compiler,
|
|
intptr_t characters_filled_in,
|
|
bool not_at_start) {
|
|
not_at_start = (not_at_start || not_at_start_);
|
|
intptr_t choice_count = alternatives_->length();
|
|
ASSERT(choice_count > 0);
|
|
(*alternatives_)[0].node()->GetQuickCheckDetails(
|
|
details, compiler, characters_filled_in, not_at_start);
|
|
for (intptr_t i = 1; i < choice_count; i++) {
|
|
QuickCheckDetails new_details(details->characters());
|
|
RegExpNode* node = (*alternatives_)[i].node();
|
|
node->GetQuickCheckDetails(&new_details, compiler, characters_filled_in,
|
|
not_at_start);
|
|
// Here we merge the quick match details of the two branches.
|
|
details->Merge(&new_details, characters_filled_in);
|
|
}
|
|
}
|
|
|
|
// Check for [0-9A-Z_a-z].
|
|
static void EmitWordCheck(RegExpMacroAssembler* assembler,
|
|
BlockLabel* word,
|
|
BlockLabel* non_word,
|
|
bool fall_through_on_word) {
|
|
if (assembler->CheckSpecialCharacterClass(
|
|
fall_through_on_word ? 'w' : 'W',
|
|
fall_through_on_word ? non_word : word)) {
|
|
// Optimized implementation available.
|
|
return;
|
|
}
|
|
assembler->CheckCharacterGT('z', non_word);
|
|
assembler->CheckCharacterLT('0', non_word);
|
|
assembler->CheckCharacterGT('a' - 1, word);
|
|
assembler->CheckCharacterLT('9' + 1, word);
|
|
assembler->CheckCharacterLT('A', non_word);
|
|
assembler->CheckCharacterLT('Z' + 1, word);
|
|
if (fall_through_on_word) {
|
|
assembler->CheckNotCharacter('_', non_word);
|
|
} else {
|
|
assembler->CheckCharacter('_', word);
|
|
}
|
|
}
|
|
|
|
// Emit the code to check for a ^ in multiline mode (1-character lookbehind
|
|
// that matches newline or the start of input).
|
|
static void EmitHat(RegExpCompiler* compiler,
|
|
RegExpNode* on_success,
|
|
Trace* trace) {
|
|
RegExpMacroAssembler* assembler = compiler->macro_assembler();
|
|
// We will be loading the previous character into the current character
|
|
// register.
|
|
Trace new_trace(*trace);
|
|
new_trace.InvalidateCurrentCharacter();
|
|
|
|
BlockLabel ok;
|
|
if (new_trace.cp_offset() == 0) {
|
|
// The start of input counts as a newline in this context, so skip to
|
|
// ok if we are at the start.
|
|
assembler->CheckAtStart(&ok);
|
|
}
|
|
// We already checked that we are not at the start of input so it must be
|
|
// OK to load the previous character.
|
|
assembler->LoadCurrentCharacter(new_trace.cp_offset() - 1,
|
|
new_trace.backtrack(), false);
|
|
if (!assembler->CheckSpecialCharacterClass('n', new_trace.backtrack())) {
|
|
// Newline means \n, \r, 0x2028 or 0x2029.
|
|
if (!compiler->one_byte()) {
|
|
assembler->CheckCharacterAfterAnd(0x2028, 0xfffe, &ok);
|
|
}
|
|
assembler->CheckCharacter('\n', &ok);
|
|
assembler->CheckNotCharacter('\r', new_trace.backtrack());
|
|
}
|
|
assembler->BindBlock(&ok);
|
|
on_success->Emit(compiler, &new_trace);
|
|
}
|
|
|
|
// Emit the code to handle \b and \B (word-boundary or non-word-boundary).
|
|
void AssertionNode::EmitBoundaryCheck(RegExpCompiler* compiler, Trace* trace) {
|
|
RegExpMacroAssembler* assembler = compiler->macro_assembler();
|
|
Trace::TriBool next_is_word_character = Trace::UNKNOWN;
|
|
bool not_at_start = (trace->at_start() == Trace::FALSE_VALUE);
|
|
BoyerMooreLookahead* lookahead = bm_info(not_at_start);
|
|
if (lookahead == NULL) {
|
|
intptr_t eats_at_least =
|
|
Utils::Minimum(kMaxLookaheadForBoyerMoore,
|
|
EatsAtLeast(kMaxLookaheadForBoyerMoore, kRecursionBudget,
|
|
not_at_start));
|
|
if (eats_at_least >= 1) {
|
|
BoyerMooreLookahead* bm =
|
|
new (Z) BoyerMooreLookahead(eats_at_least, compiler, Z);
|
|
FillInBMInfo(0, kRecursionBudget, bm, not_at_start);
|
|
if (bm->at(0)->is_non_word()) next_is_word_character = Trace::FALSE_VALUE;
|
|
if (bm->at(0)->is_word()) next_is_word_character = Trace::TRUE_VALUE;
|
|
}
|
|
} else {
|
|
if (lookahead->at(0)->is_non_word())
|
|
next_is_word_character = Trace::FALSE_VALUE;
|
|
if (lookahead->at(0)->is_word()) next_is_word_character = Trace::TRUE_VALUE;
|
|
}
|
|
bool at_boundary = (assertion_type_ == AssertionNode::AT_BOUNDARY);
|
|
if (next_is_word_character == Trace::UNKNOWN) {
|
|
BlockLabel before_non_word;
|
|
BlockLabel before_word;
|
|
if (trace->characters_preloaded() != 1) {
|
|
assembler->LoadCurrentCharacter(trace->cp_offset(), &before_non_word);
|
|
}
|
|
// Fall through on non-word.
|
|
EmitWordCheck(assembler, &before_word, &before_non_word, false);
|
|
// Next character is not a word character.
|
|
assembler->BindBlock(&before_non_word);
|
|
BlockLabel ok;
|
|
// Backtrack on \B (non-boundary check) if previous is a word,
|
|
// since we know next *is not* a word and this would be a boundary.
|
|
BacktrackIfPrevious(compiler, trace, at_boundary ? kIsNonWord : kIsWord);
|
|
|
|
if (!assembler->IsClosed()) {
|
|
assembler->GoTo(&ok);
|
|
}
|
|
|
|
assembler->BindBlock(&before_word);
|
|
BacktrackIfPrevious(compiler, trace, at_boundary ? kIsWord : kIsNonWord);
|
|
assembler->BindBlock(&ok);
|
|
} else if (next_is_word_character == Trace::TRUE_VALUE) {
|
|
BacktrackIfPrevious(compiler, trace, at_boundary ? kIsWord : kIsNonWord);
|
|
} else {
|
|
ASSERT(next_is_word_character == Trace::FALSE_VALUE);
|
|
BacktrackIfPrevious(compiler, trace, at_boundary ? kIsNonWord : kIsWord);
|
|
}
|
|
}
|
|
|
|
void AssertionNode::BacktrackIfPrevious(
|
|
RegExpCompiler* compiler,
|
|
Trace* trace,
|
|
AssertionNode::IfPrevious backtrack_if_previous) {
|
|
RegExpMacroAssembler* assembler = compiler->macro_assembler();
|
|
Trace new_trace(*trace);
|
|
new_trace.InvalidateCurrentCharacter();
|
|
|
|
BlockLabel fall_through, dummy;
|
|
|
|
BlockLabel* non_word = backtrack_if_previous == kIsNonWord
|
|
? new_trace.backtrack()
|
|
: &fall_through;
|
|
BlockLabel* word = backtrack_if_previous == kIsNonWord
|
|
? &fall_through
|
|
: new_trace.backtrack();
|
|
|
|
if (new_trace.cp_offset() == 0) {
|
|
// The start of input counts as a non-word character, so the question is
|
|
// decided if we are at the start.
|
|
assembler->CheckAtStart(non_word);
|
|
}
|
|
// We already checked that we are not at the start of input so it must be
|
|
// OK to load the previous character.
|
|
assembler->LoadCurrentCharacter(new_trace.cp_offset() - 1, &dummy, false);
|
|
EmitWordCheck(assembler, word, non_word, backtrack_if_previous == kIsNonWord);
|
|
|
|
assembler->BindBlock(&fall_through);
|
|
on_success()->Emit(compiler, &new_trace);
|
|
}
|
|
|
|
void AssertionNode::GetQuickCheckDetails(QuickCheckDetails* details,
|
|
RegExpCompiler* compiler,
|
|
intptr_t filled_in,
|
|
bool not_at_start) {
|
|
if (assertion_type_ == AT_START && not_at_start) {
|
|
details->set_cannot_match();
|
|
return;
|
|
}
|
|
return on_success()->GetQuickCheckDetails(details, compiler, filled_in,
|
|
not_at_start);
|
|
}
|
|
|
|
void AssertionNode::Emit(RegExpCompiler* compiler, Trace* trace) {
|
|
RegExpMacroAssembler* assembler = compiler->macro_assembler();
|
|
switch (assertion_type_) {
|
|
case AT_END: {
|
|
BlockLabel ok;
|
|
assembler->CheckPosition(trace->cp_offset(), &ok);
|
|
assembler->GoTo(trace->backtrack());
|
|
assembler->BindBlock(&ok);
|
|
break;
|
|
}
|
|
case AT_START: {
|
|
if (trace->at_start() == Trace::FALSE_VALUE) {
|
|
assembler->GoTo(trace->backtrack());
|
|
return;
|
|
}
|
|
if (trace->at_start() == Trace::UNKNOWN) {
|
|
assembler->CheckNotAtStart(trace->cp_offset(), trace->backtrack());
|
|
Trace at_start_trace = *trace;
|
|
at_start_trace.set_at_start(Trace::TRUE_VALUE);
|
|
on_success()->Emit(compiler, &at_start_trace);
|
|
return;
|
|
}
|
|
} break;
|
|
case AFTER_NEWLINE:
|
|
EmitHat(compiler, on_success(), trace);
|
|
return;
|
|
case AT_BOUNDARY:
|
|
case AT_NON_BOUNDARY: {
|
|
EmitBoundaryCheck(compiler, trace);
|
|
return;
|
|
}
|
|
}
|
|
on_success()->Emit(compiler, trace);
|
|
}
|
|
|
|
static bool DeterminedAlready(QuickCheckDetails* quick_check, intptr_t offset) {
|
|
if (quick_check == NULL) return false;
|
|
if (offset >= quick_check->characters()) return false;
|
|
return quick_check->positions(offset)->determines_perfectly;
|
|
}
|
|
|
|
static void UpdateBoundsCheck(intptr_t index, intptr_t* checked_up_to) {
|
|
if (index > *checked_up_to) {
|
|
*checked_up_to = index;
|
|
}
|
|
}
|
|
|
|
// We call this repeatedly to generate code for each pass over the text node.
|
|
// The passes are in increasing order of difficulty because we hope one
|
|
// of the first passes will fail in which case we are saved the work of the
|
|
// later passes. for example for the case independent regexp /%[asdfghjkl]a/
|
|
// we will check the '%' in the first pass, the case independent 'a' in the
|
|
// second pass and the character class in the last pass.
|
|
//
|
|
// The passes are done from right to left, so for example to test for /bar/
|
|
// we will first test for an 'r' with offset 2, then an 'a' with offset 1
|
|
// and then a 'b' with offset 0. This means we can avoid the end-of-input
|
|
// bounds check most of the time. In the example we only need to check for
|
|
// end-of-input when loading the putative 'r'.
|
|
//
|
|
// A slight complication involves the fact that the first character may already
|
|
// be fetched into a register by the previous node. In this case we want to
|
|
// do the test for that character first. We do this in separate passes. The
|
|
// 'preloaded' argument indicates that we are doing such a 'pass'. If such a
|
|
// pass has been performed then subsequent passes will have true in
|
|
// first_element_checked to indicate that that character does not need to be
|
|
// checked again.
|
|
//
|
|
// In addition to all this we are passed a Trace, which can
|
|
// contain an AlternativeGeneration object. In this AlternativeGeneration
|
|
// object we can see details of any quick check that was already passed in
|
|
// order to get to the code we are now generating. The quick check can involve
|
|
// loading characters, which means we do not need to recheck the bounds
|
|
// up to the limit the quick check already checked. In addition the quick
|
|
// check can have involved a mask and compare operation which may simplify
|
|
// or obviate the need for further checks at some character positions.
|
|
void TextNode::TextEmitPass(RegExpCompiler* compiler,
|
|
TextEmitPassType pass,
|
|
bool preloaded,
|
|
Trace* trace,
|
|
bool first_element_checked,
|
|
intptr_t* checked_up_to) {
|
|
RegExpMacroAssembler* assembler = compiler->macro_assembler();
|
|
bool one_byte = compiler->one_byte();
|
|
BlockLabel* backtrack = trace->backtrack();
|
|
QuickCheckDetails* quick_check = trace->quick_check_performed();
|
|
intptr_t element_count = elms_->length();
|
|
intptr_t backward_offset = read_backward() ? -Length() : 0;
|
|
for (intptr_t i = preloaded ? 0 : element_count - 1; i >= 0; i--) {
|
|
TextElement elm = elms_->At(i);
|
|
intptr_t cp_offset = trace->cp_offset() + elm.cp_offset() + backward_offset;
|
|
if (elm.text_type() == TextElement::ATOM) {
|
|
ZoneGrowableArray<uint16_t>* quarks = elm.atom()->data();
|
|
for (intptr_t j = preloaded ? 0 : quarks->length() - 1; j >= 0; j--) {
|
|
if (SkipPass(pass, elm.atom()->ignore_case())) continue;
|
|
if (first_element_checked && i == 0 && j == 0) continue;
|
|
if (DeterminedAlready(quick_check, elm.cp_offset() + j)) continue;
|
|
EmitCharacterFunction* emit_function = NULL;
|
|
uint16_t quark = quarks->At(j);
|
|
if (elm.atom()->ignore_case()) {
|
|
// Everywhere else we assume that a non-Latin-1 character cannot match
|
|
// a Latin-1 character. Avoid the cases where this is assumption is
|
|
// invalid by using the Latin1 equivalent instead.
|
|
quark = Latin1::TryConvertToLatin1(quark);
|
|
}
|
|
switch (pass) {
|
|
case NON_LATIN1_MATCH:
|
|
ASSERT(one_byte);
|
|
if (quark > Symbols::kMaxOneCharCodeSymbol) {
|
|
assembler->GoTo(backtrack);
|
|
return;
|
|
}
|
|
break;
|
|
case NON_LETTER_CHARACTER_MATCH:
|
|
emit_function = &EmitAtomNonLetter;
|
|
break;
|
|
case SIMPLE_CHARACTER_MATCH:
|
|
emit_function = &EmitSimpleCharacter;
|
|
break;
|
|
case CASE_CHARACTER_MATCH:
|
|
emit_function = &EmitAtomLetter;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
if (emit_function != NULL) {
|
|
const bool bounds_check =
|
|
*checked_up_to < (cp_offset + j) || read_backward();
|
|
bool bound_checked =
|
|
emit_function(Z, compiler, quarks->At(j), backtrack,
|
|
cp_offset + j, bounds_check, preloaded);
|
|
if (bound_checked) UpdateBoundsCheck(cp_offset + j, checked_up_to);
|
|
}
|
|
}
|
|
} else {
|
|
ASSERT(elm.text_type() == TextElement::CHAR_CLASS);
|
|
if (pass == CHARACTER_CLASS_MATCH) {
|
|
if (first_element_checked && i == 0) continue;
|
|
if (DeterminedAlready(quick_check, elm.cp_offset())) continue;
|
|
RegExpCharacterClass* cc = elm.char_class();
|
|
bool bounds_check = *checked_up_to < cp_offset || read_backward();
|
|
EmitCharClass(assembler, cc, one_byte, backtrack, cp_offset,
|
|
bounds_check, preloaded, Z);
|
|
UpdateBoundsCheck(cp_offset, checked_up_to);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
intptr_t TextNode::Length() {
|
|
TextElement elm = elms_->Last();
|
|
ASSERT(elm.cp_offset() >= 0);
|
|
return elm.cp_offset() + elm.length();
|
|
}
|
|
|
|
bool TextNode::SkipPass(intptr_t intptr_t_pass, bool ignore_case) {
|
|
TextEmitPassType pass = static_cast<TextEmitPassType>(intptr_t_pass);
|
|
if (ignore_case) {
|
|
return pass == SIMPLE_CHARACTER_MATCH;
|
|
} else {
|
|
return pass == NON_LETTER_CHARACTER_MATCH || pass == CASE_CHARACTER_MATCH;
|
|
}
|
|
}
|
|
|
|
TextNode* TextNode::CreateForCharacterRanges(
|
|
ZoneGrowableArray<CharacterRange>* ranges,
|
|
bool read_backward,
|
|
RegExpNode* on_success,
|
|
RegExpFlags flags) {
|
|
ASSERT(ranges != nullptr);
|
|
ZoneGrowableArray<TextElement>* elms = new ZoneGrowableArray<TextElement>(1);
|
|
elms->Add(TextElement::CharClass(new RegExpCharacterClass(ranges, flags)));
|
|
return new TextNode(elms, read_backward, on_success);
|
|
}
|
|
|
|
TextNode* TextNode::CreateForSurrogatePair(CharacterRange lead,
|
|
CharacterRange trail,
|
|
bool read_backward,
|
|
RegExpNode* on_success,
|
|
RegExpFlags flags) {
|
|
auto lead_ranges = CharacterRange::List(on_success->zone(), lead);
|
|
auto trail_ranges = CharacterRange::List(on_success->zone(), trail);
|
|
auto elms = new ZoneGrowableArray<TextElement>(2);
|
|
|
|
elms->Add(
|
|
TextElement::CharClass(new RegExpCharacterClass(lead_ranges, flags)));
|
|
elms->Add(
|
|
TextElement::CharClass(new RegExpCharacterClass(trail_ranges, flags)));
|
|
|
|
return new TextNode(elms, read_backward, on_success);
|
|
}
|
|
|
|
// This generates the code to match a text node. A text node can contain
|
|
// straight character sequences (possibly to be matched in a case-independent
|
|
// way) and character classes. For efficiency we do not do this in a single
|
|
// pass from left to right. Instead we pass over the text node several times,
|
|
// emitting code for some character positions every time. See the comment on
|
|
// TextEmitPass for details.
|
|
void TextNode::Emit(RegExpCompiler* compiler, Trace* trace) {
|
|
LimitResult limit_result = LimitVersions(compiler, trace);
|
|
if (limit_result == DONE) return;
|
|
ASSERT(limit_result == CONTINUE);
|
|
|
|
if (trace->cp_offset() + Length() > RegExpMacroAssembler::kMaxCPOffset) {
|
|
compiler->SetRegExpTooBig();
|
|
return;
|
|
}
|
|
|
|
if (compiler->one_byte()) {
|
|
intptr_t dummy = 0;
|
|
TextEmitPass(compiler, NON_LATIN1_MATCH, false, trace, false, &dummy);
|
|
}
|
|
|
|
bool first_elt_done = false;
|
|
intptr_t bound_checked_to = trace->cp_offset() - 1;
|
|
bound_checked_to += trace->bound_checked_up_to();
|
|
|
|
// If a character is preloaded into the current character register then
|
|
// check that now.
|
|
if (trace->characters_preloaded() == 1) {
|
|
for (intptr_t pass = kFirstRealPass; pass <= kLastPass; pass++) {
|
|
TextEmitPass(compiler, static_cast<TextEmitPassType>(pass), true, trace,
|
|
false, &bound_checked_to);
|
|
}
|
|
first_elt_done = true;
|
|
}
|
|
|
|
for (intptr_t pass = kFirstRealPass; pass <= kLastPass; pass++) {
|
|
TextEmitPass(compiler, static_cast<TextEmitPassType>(pass), false, trace,
|
|
first_elt_done, &bound_checked_to);
|
|
}
|
|
|
|
Trace successor_trace(*trace);
|
|
// If we advance backward, we may end up at the start.
|
|
successor_trace.AdvanceCurrentPositionInTrace(
|
|
read_backward() ? -Length() : Length(), compiler);
|
|
successor_trace.set_at_start(read_backward() ? Trace::UNKNOWN
|
|
: Trace::FALSE_VALUE);
|
|
RecursionCheck rc(compiler);
|
|
on_success()->Emit(compiler, &successor_trace);
|
|
}
|
|
|
|
void Trace::InvalidateCurrentCharacter() {
|
|
characters_preloaded_ = 0;
|
|
}
|
|
|
|
void Trace::AdvanceCurrentPositionInTrace(intptr_t by,
|
|
RegExpCompiler* compiler) {
|
|
// We don't have an instruction for shifting the current character register
|
|
// down or for using a shifted value for anything so lets just forget that
|
|
// we preloaded any characters into it.
|
|
characters_preloaded_ = 0;
|
|
// Adjust the offsets of the quick check performed information. This
|
|
// information is used to find out what we already determined about the
|
|
// characters by means of mask and compare.
|
|
quick_check_performed_.Advance(by, compiler->one_byte());
|
|
cp_offset_ += by;
|
|
if (cp_offset_ > RegExpMacroAssembler::kMaxCPOffset) {
|
|
compiler->SetRegExpTooBig();
|
|
cp_offset_ = 0;
|
|
}
|
|
bound_checked_up_to_ =
|
|
Utils::Maximum(static_cast<intptr_t>(0), bound_checked_up_to_ - by);
|
|
}
|
|
|
|
void TextNode::MakeCaseIndependent(bool is_one_byte) {
|
|
intptr_t element_count = elms_->length();
|
|
for (intptr_t i = 0; i < element_count; i++) {
|
|
TextElement elm = elms_->At(i);
|
|
if (elm.text_type() == TextElement::CHAR_CLASS) {
|
|
RegExpCharacterClass* cc = elm.char_class();
|
|
bool case_equivalents_already_added =
|
|
cc->flags().NeedsUnicodeCaseEquivalents();
|
|
if (cc->flags().IgnoreCase() && !case_equivalents_already_added) {
|
|
// None of the standard character classes is different in the case
|
|
// independent case and it slows us down if we don't know that.
|
|
if (cc->is_standard()) continue;
|
|
CharacterRange::AddCaseEquivalents(cc->ranges(), is_one_byte, Z);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
intptr_t TextNode::GreedyLoopTextLength() {
|
|
TextElement elm = elms_->At(elms_->length() - 1);
|
|
return elm.cp_offset() + elm.length();
|
|
}
|
|
|
|
RegExpNode* TextNode::GetSuccessorOfOmnivorousTextNode(
|
|
RegExpCompiler* compiler) {
|
|
if (read_backward()) return nullptr;
|
|
if (elms_->length() != 1) return NULL;
|
|
TextElement elm = elms_->At(0);
|
|
if (elm.text_type() != TextElement::CHAR_CLASS) return NULL;
|
|
RegExpCharacterClass* node = elm.char_class();
|
|
ZoneGrowableArray<CharacterRange>* ranges = node->ranges();
|
|
if (!CharacterRange::IsCanonical(ranges)) {
|
|
CharacterRange::Canonicalize(ranges);
|
|
}
|
|
if (node->is_negated()) {
|
|
return ranges->length() == 0 ? on_success() : NULL;
|
|
}
|
|
if (ranges->length() != 1) return NULL;
|
|
uint32_t max_char;
|
|
if (compiler->one_byte()) {
|
|
max_char = Symbols::kMaxOneCharCodeSymbol;
|
|
} else {
|
|
max_char = Utf16::kMaxCodeUnit;
|
|
}
|
|
return ranges->At(0).IsEverything(max_char) ? on_success() : NULL;
|
|
}
|
|
|
|
// Finds the fixed match length of a sequence of nodes that goes from
|
|
// this alternative and back to this choice node. If there are variable
|
|
// length nodes or other complications in the way then return a sentinel
|
|
// value indicating that a greedy loop cannot be constructed.
|
|
intptr_t ChoiceNode::GreedyLoopTextLengthForAlternative(
|
|
const GuardedAlternative* alternative) {
|
|
intptr_t length = 0;
|
|
RegExpNode* node = alternative->node();
|
|
// Later we will generate code for all these text nodes using recursion
|
|
// so we have to limit the max number.
|
|
intptr_t recursion_depth = 0;
|
|
while (node != this) {
|
|
if (recursion_depth++ > RegExpCompiler::kMaxRecursion) {
|
|
return kNodeIsTooComplexForGreedyLoops;
|
|
}
|
|
intptr_t node_length = node->GreedyLoopTextLength();
|
|
if (node_length == kNodeIsTooComplexForGreedyLoops) {
|
|
return kNodeIsTooComplexForGreedyLoops;
|
|
}
|
|
length += node_length;
|
|
SeqRegExpNode* seq_node = static_cast<SeqRegExpNode*>(node);
|
|
node = seq_node->on_success();
|
|
}
|
|
return read_backward() ? -length : length;
|
|
}
|
|
|
|
void LoopChoiceNode::AddLoopAlternative(GuardedAlternative alt) {
|
|
ASSERT(loop_node_ == NULL);
|
|
AddAlternative(alt);
|
|
loop_node_ = alt.node();
|
|
}
|
|
|
|
void LoopChoiceNode::AddContinueAlternative(GuardedAlternative alt) {
|
|
ASSERT(continue_node_ == NULL);
|
|
AddAlternative(alt);
|
|
continue_node_ = alt.node();
|
|
}
|
|
|
|
void LoopChoiceNode::Emit(RegExpCompiler* compiler, Trace* trace) {
|
|
RegExpMacroAssembler* macro_assembler = compiler->macro_assembler();
|
|
if (trace->stop_node() == this) {
|
|
// Back edge of greedy optimized loop node graph.
|
|
intptr_t text_length =
|
|
GreedyLoopTextLengthForAlternative(&alternatives_->At(0));
|
|
ASSERT(text_length != kNodeIsTooComplexForGreedyLoops);
|
|
// Update the counter-based backtracking info on the stack. This is an
|
|
// optimization for greedy loops (see below).
|
|
ASSERT(trace->cp_offset() == text_length);
|
|
macro_assembler->AdvanceCurrentPosition(text_length);
|
|
macro_assembler->GoTo(trace->loop_label());
|
|
return;
|
|
}
|
|
ASSERT(trace->stop_node() == NULL);
|
|
if (!trace->is_trivial()) {
|
|
trace->Flush(compiler, this);
|
|
return;
|
|
}
|
|
ChoiceNode::Emit(compiler, trace);
|
|
}
|
|
|
|
intptr_t ChoiceNode::CalculatePreloadCharacters(RegExpCompiler* compiler,
|
|
intptr_t eats_at_least) {
|
|
intptr_t preload_characters =
|
|
Utils::Minimum(static_cast<intptr_t>(4), eats_at_least);
|
|
if (compiler->macro_assembler()->CanReadUnaligned()) {
|
|
bool one_byte = compiler->one_byte();
|
|
if (one_byte) {
|
|
if (preload_characters > 4) preload_characters = 4;
|
|
// We can't preload 3 characters because there is no machine instruction
|
|
// to do that. We can't just load 4 because we could be reading
|
|
// beyond the end of the string, which could cause a memory fault.
|
|
if (preload_characters == 3) preload_characters = 2;
|
|
} else {
|
|
if (preload_characters > 2) preload_characters = 2;
|
|
}
|
|
} else {
|
|
if (preload_characters > 1) preload_characters = 1;
|
|
}
|
|
return preload_characters;
|
|
}
|
|
|
|
// This structure is used when generating the alternatives in a choice node. It
|
|
// records the way the alternative is being code generated.
|
|
struct AlternativeGeneration {
|
|
AlternativeGeneration()
|
|
: possible_success(),
|
|
expects_preload(false),
|
|
after(),
|
|
quick_check_details() {}
|
|
BlockLabel possible_success;
|
|
bool expects_preload;
|
|
BlockLabel after;
|
|
QuickCheckDetails quick_check_details;
|
|
};
|
|
|
|
// Creates a list of AlternativeGenerations. If the list has a reasonable
|
|
// size then it is on the stack, otherwise the excess is on the heap.
|
|
class AlternativeGenerationList {
|
|
public:
|
|
explicit AlternativeGenerationList(intptr_t count) : count_(count) {
|
|
ASSERT(count >= 0);
|
|
if (count > kAFew) {
|
|
excess_alt_gens_.reset(new AlternativeGeneration[count - kAFew]);
|
|
}
|
|
}
|
|
|
|
AlternativeGeneration* at(intptr_t i) {
|
|
ASSERT(0 <= i);
|
|
ASSERT(i < count_);
|
|
if (i < kAFew) {
|
|
return &a_few_alt_gens_[i];
|
|
}
|
|
return &excess_alt_gens_[i - kAFew];
|
|
}
|
|
|
|
private:
|
|
static const intptr_t kAFew = 10;
|
|
|
|
intptr_t count_;
|
|
AlternativeGeneration a_few_alt_gens_[kAFew];
|
|
std::unique_ptr<AlternativeGeneration[]> excess_alt_gens_;
|
|
|
|
DISALLOW_ALLOCATION();
|
|
DISALLOW_COPY_AND_ASSIGN(AlternativeGenerationList);
|
|
};
|
|
|
|
static const int32_t kRangeEndMarker = Utf::kMaxCodePoint + 1;
|
|
|
|
// The '2' variant is inclusive from and exclusive to.
|
|
// This covers \s as defined in ECMA-262 5.1, 15.10.2.12,
|
|
// which include WhiteSpace (7.2) or LineTerminator (7.3) values.
|
|
// 0x180E has been removed from Unicode's Zs category and thus
|
|
// from ECMAScript's WhiteSpace category as of Unicode 6.3.
|
|
static const int32_t kSpaceRanges[] = {
|
|
'\t', '\r' + 1, ' ', ' ' + 1, 0x00A0, 0x00A1, 0x1680,
|
|
0x1681, 0x2000, 0x200B, 0x2028, 0x202A, 0x202F, 0x2030,
|
|
0x205F, 0x2060, 0x3000, 0x3001, 0xFEFF, 0xFF00, kRangeEndMarker};
|
|
static const intptr_t kSpaceRangeCount = ARRAY_SIZE(kSpaceRanges);
|
|
static const int32_t kWordRanges[] = {
|
|
'0', '9' + 1, 'A', 'Z' + 1, '_', '_' + 1, 'a', 'z' + 1, kRangeEndMarker};
|
|
static const intptr_t kWordRangeCount = ARRAY_SIZE(kWordRanges);
|
|
static const int32_t kDigitRanges[] = {'0', '9' + 1, kRangeEndMarker};
|
|
static const intptr_t kDigitRangeCount = ARRAY_SIZE(kDigitRanges);
|
|
static const int32_t kSurrogateRanges[] = {0xd800, 0xe000, kRangeEndMarker};
|
|
static const intptr_t kSurrogateRangeCount = ARRAY_SIZE(kSurrogateRanges);
|
|
static const int32_t kLineTerminatorRanges[] = {
|
|
0x000A, 0x000B, 0x000D, 0x000E, 0x2028, 0x202A, kRangeEndMarker};
|
|
static const intptr_t kLineTerminatorRangeCount =
|
|
ARRAY_SIZE(kLineTerminatorRanges);
|
|
|
|
void BoyerMoorePositionInfo::Set(intptr_t character) {
|
|
SetInterval(Interval(character, character));
|
|
}
|
|
|
|
void BoyerMoorePositionInfo::SetInterval(const Interval& interval) {
|
|
s_ = AddRange(s_, kSpaceRanges, kSpaceRangeCount, interval);
|
|
w_ = AddRange(w_, kWordRanges, kWordRangeCount, interval);
|
|
d_ = AddRange(d_, kDigitRanges, kDigitRangeCount, interval);
|
|
surrogate_ =
|
|
AddRange(surrogate_, kSurrogateRanges, kSurrogateRangeCount, interval);
|
|
if (interval.to() - interval.from() >= kMapSize - 1) {
|
|
if (map_count_ != kMapSize) {
|
|
map_count_ = kMapSize;
|
|
for (intptr_t i = 0; i < kMapSize; i++)
|
|
(*map_)[i] = true;
|
|
}
|
|
return;
|
|
}
|
|
for (intptr_t i = interval.from(); i <= interval.to(); i++) {
|
|
intptr_t mod_character = (i & kMask);
|
|
if (!map_->At(mod_character)) {
|
|
map_count_++;
|
|
(*map_)[mod_character] = true;
|
|
}
|
|
if (map_count_ == kMapSize) return;
|
|
}
|
|
}
|
|
|
|
void BoyerMoorePositionInfo::SetAll() {
|
|
s_ = w_ = d_ = kLatticeUnknown;
|
|
if (map_count_ != kMapSize) {
|
|
map_count_ = kMapSize;
|
|
for (intptr_t i = 0; i < kMapSize; i++)
|
|
(*map_)[i] = true;
|
|
}
|
|
}
|
|
|
|
BoyerMooreLookahead::BoyerMooreLookahead(intptr_t length,
|
|
RegExpCompiler* compiler,
|
|
Zone* zone)
|
|
: length_(length), compiler_(compiler) {
|
|
if (compiler->one_byte()) {
|
|
max_char_ = Symbols::kMaxOneCharCodeSymbol;
|
|
} else {
|
|
max_char_ = Utf16::kMaxCodeUnit;
|
|
}
|
|
bitmaps_ = new (zone) ZoneGrowableArray<BoyerMoorePositionInfo*>(length);
|
|
for (intptr_t i = 0; i < length; i++) {
|
|
bitmaps_->Add(new (zone) BoyerMoorePositionInfo(zone));
|
|
}
|
|
}
|
|
|
|
// Find the longest range of lookahead that has the fewest number of different
|
|
// characters that can occur at a given position. Since we are optimizing two
|
|
// different parameters at once this is a tradeoff.
|
|
bool BoyerMooreLookahead::FindWorthwhileInterval(intptr_t* from, intptr_t* to) {
|
|
intptr_t biggest_points = 0;
|
|
// If more than 32 characters out of 128 can occur it is unlikely that we can
|
|
// be lucky enough to step forwards much of the time.
|
|
const intptr_t kMaxMax = 32;
|
|
for (intptr_t max_number_of_chars = 4; max_number_of_chars < kMaxMax;
|
|
max_number_of_chars *= 2) {
|
|
biggest_points =
|
|
FindBestInterval(max_number_of_chars, biggest_points, from, to);
|
|
}
|
|
if (biggest_points == 0) return false;
|
|
return true;
|
|
}
|
|
|
|
// Find the highest-points range between 0 and length_ where the character
|
|
// information is not too vague. 'Too vague' means that there are more than
|
|
// max_number_of_chars that can occur at this position. Calculates the number
|
|
// of points as the product of width-of-the-range and
|
|
// probability-of-finding-one-of-the-characters, where the probability is
|
|
// calculated using the frequency distribution of the sample subject string.
|
|
intptr_t BoyerMooreLookahead::FindBestInterval(intptr_t max_number_of_chars,
|
|
intptr_t old_biggest_points,
|
|
intptr_t* from,
|
|
intptr_t* to) {
|
|
intptr_t biggest_points = old_biggest_points;
|
|
static const intptr_t kSize = RegExpMacroAssembler::kTableSize;
|
|
for (intptr_t i = 0; i < length_;) {
|
|
while (i < length_ && Count(i) > max_number_of_chars)
|
|
i++;
|
|
if (i == length_) break;
|
|
intptr_t remembered_from = i;
|
|
bool union_map[kSize];
|
|
for (intptr_t j = 0; j < kSize; j++)
|
|
union_map[j] = false;
|
|
while (i < length_ && Count(i) <= max_number_of_chars) {
|
|
BoyerMoorePositionInfo* map = bitmaps_->At(i);
|
|
for (intptr_t j = 0; j < kSize; j++)
|
|
union_map[j] |= map->at(j);
|
|
i++;
|
|
}
|
|
intptr_t frequency = 0;
|
|
for (intptr_t j = 0; j < kSize; j++) {
|
|
if (union_map[j]) {
|
|
// Add 1 to the frequency to give a small per-character boost for
|
|
// the cases where our sampling is not good enough and many
|
|
// characters have a frequency of zero. This means the frequency
|
|
// can theoretically be up to 2*kSize though we treat it mostly as
|
|
// a fraction of kSize.
|
|
frequency += compiler_->frequency_collator()->Frequency(j) + 1;
|
|
}
|
|
}
|
|
// We use the probability of skipping times the distance we are skipping to
|
|
// judge the effectiveness of this. Actually we have a cut-off: By
|
|
// dividing by 2 we switch off the skipping if the probability of skipping
|
|
// is less than 50%. This is because the multibyte mask-and-compare
|
|
// skipping in quickcheck is more likely to do well on this case.
|
|
bool in_quickcheck_range =
|
|
((i - remembered_from < 4) ||
|
|
(compiler_->one_byte() ? remembered_from <= 4 : remembered_from <= 2));
|
|
// Called 'probability' but it is only a rough estimate and can actually
|
|
// be outside the 0-kSize range.
|
|
intptr_t probability =
|
|
(in_quickcheck_range ? kSize / 2 : kSize) - frequency;
|
|
intptr_t points = (i - remembered_from) * probability;
|
|
if (points > biggest_points) {
|
|
*from = remembered_from;
|
|
*to = i - 1;
|
|
biggest_points = points;
|
|
}
|
|
}
|
|
return biggest_points;
|
|
}
|
|
|
|
// Take all the characters that will not prevent a successful match if they
|
|
// occur in the subject string in the range between min_lookahead and
|
|
// max_lookahead (inclusive) measured from the current position. If the
|
|
// character at max_lookahead offset is not one of these characters, then we
|
|
// can safely skip forwards by the number of characters in the range.
|
|
intptr_t BoyerMooreLookahead::GetSkipTable(
|
|
intptr_t min_lookahead,
|
|
intptr_t max_lookahead,
|
|
const TypedData& boolean_skip_table) {
|
|
const intptr_t kSize = RegExpMacroAssembler::kTableSize;
|
|
|
|
const intptr_t kSkipArrayEntry = 0;
|
|
const intptr_t kDontSkipArrayEntry = 1;
|
|
|
|
for (intptr_t i = 0; i < kSize; i++) {
|
|
boolean_skip_table.SetUint8(i, kSkipArrayEntry);
|
|
}
|
|
intptr_t skip = max_lookahead + 1 - min_lookahead;
|
|
|
|
for (intptr_t i = max_lookahead; i >= min_lookahead; i--) {
|
|
BoyerMoorePositionInfo* map = bitmaps_->At(i);
|
|
for (intptr_t j = 0; j < kSize; j++) {
|
|
if (map->at(j)) {
|
|
boolean_skip_table.SetUint8(j, kDontSkipArrayEntry);
|
|
}
|
|
}
|
|
}
|
|
|
|
return skip;
|
|
}
|
|
|
|
// See comment above on the implementation of GetSkipTable.
|
|
void BoyerMooreLookahead::EmitSkipInstructions(RegExpMacroAssembler* masm) {
|
|
const intptr_t kSize = RegExpMacroAssembler::kTableSize;
|
|
|
|
intptr_t min_lookahead = 0;
|
|
intptr_t max_lookahead = 0;
|
|
|
|
if (!FindWorthwhileInterval(&min_lookahead, &max_lookahead)) return;
|
|
|
|
bool found_single_character = false;
|
|
intptr_t single_character = 0;
|
|
for (intptr_t i = max_lookahead; i >= min_lookahead; i--) {
|
|
BoyerMoorePositionInfo* map = bitmaps_->At(i);
|
|
if (map->map_count() > 1 ||
|
|
(found_single_character && map->map_count() != 0)) {
|
|
found_single_character = false;
|
|
break;
|
|
}
|
|
for (intptr_t j = 0; j < kSize; j++) {
|
|
if (map->at(j)) {
|
|
found_single_character = true;
|
|
single_character = j;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
intptr_t lookahead_width = max_lookahead + 1 - min_lookahead;
|
|
|
|
if (found_single_character && lookahead_width == 1 && max_lookahead < 3) {
|
|
// The mask-compare can probably handle this better.
|
|
return;
|
|
}
|
|
|
|
if (found_single_character) {
|
|
BlockLabel cont, again;
|
|
masm->BindBlock(&again);
|
|
masm->LoadCurrentCharacter(max_lookahead, &cont, true);
|
|
if (max_char_ > kSize) {
|
|
masm->CheckCharacterAfterAnd(single_character,
|
|
RegExpMacroAssembler::kTableMask, &cont);
|
|
} else {
|
|
masm->CheckCharacter(single_character, &cont);
|
|
}
|
|
masm->AdvanceCurrentPosition(lookahead_width);
|
|
masm->GoTo(&again);
|
|
masm->BindBlock(&cont);
|
|
return;
|
|
}
|
|
|
|
const TypedData& boolean_skip_table = TypedData::ZoneHandle(
|
|
compiler_->zone(),
|
|
TypedData::New(kTypedDataUint8ArrayCid, kSize, Heap::kOld));
|
|
intptr_t skip_distance =
|
|
GetSkipTable(min_lookahead, max_lookahead, boolean_skip_table);
|
|
ASSERT(skip_distance != 0);
|
|
|
|
BlockLabel cont, again;
|
|
|
|
masm->BindBlock(&again);
|
|
masm->CheckPreemption(/*is_backtrack=*/false);
|
|
masm->LoadCurrentCharacter(max_lookahead, &cont, true);
|
|
masm->CheckBitInTable(boolean_skip_table, &cont);
|
|
masm->AdvanceCurrentPosition(skip_distance);
|
|
masm->GoTo(&again);
|
|
masm->BindBlock(&cont);
|
|
|
|
return;
|
|
}
|
|
|
|
/* Code generation for choice nodes.
|
|
*
|
|
* We generate quick checks that do a mask and compare to eliminate a
|
|
* choice. If the quick check succeeds then it jumps to the continuation to
|
|
* do slow checks and check subsequent nodes. If it fails (the common case)
|
|
* it falls through to the next choice.
|
|
*
|
|
* Here is the desired flow graph. Nodes directly below each other imply
|
|
* fallthrough. Alternatives 1 and 2 have quick checks. Alternative
|
|
* 3 doesn't have a quick check so we have to call the slow check.
|
|
* Nodes are marked Qn for quick checks and Sn for slow checks. The entire
|
|
* regexp continuation is generated directly after the Sn node, up to the
|
|
* next GoTo if we decide to reuse some already generated code. Some
|
|
* nodes expect preload_characters to be preloaded into the current
|
|
* character register. R nodes do this preloading. Vertices are marked
|
|
* F for failures and S for success (possible success in the case of quick
|
|
* nodes). L, V, < and > are used as arrow heads.
|
|
*
|
|
* ----------> R
|
|
* |
|
|
* V
|
|
* Q1 -----> S1
|
|
* | S /
|
|
* F| /
|
|
* | F/
|
|
* | /
|
|
* | R
|
|
* | /
|
|
* V L
|
|
* Q2 -----> S2
|
|
* | S /
|
|
* F| /
|
|
* | F/
|
|
* | /
|
|
* | R
|
|
* | /
|
|
* V L
|
|
* S3
|
|
* |
|
|
* F|
|
|
* |
|
|
* R
|
|
* |
|
|
* backtrack V
|
|
* <----------Q4
|
|
* \ F |
|
|
* \ |S
|
|
* \ F V
|
|
* \-----S4
|
|
*
|
|
* For greedy loops we push the current position, then generate the code that
|
|
* eats the input specially in EmitGreedyLoop. The other choice (the
|
|
* continuation) is generated by the normal code in EmitChoices, and steps back
|
|
* in the input to the starting position when it fails to match. The loop code
|
|
* looks like this (U is the unwind code that steps back in the greedy loop).
|
|
*
|
|
* _____
|
|
* / \
|
|
* V |
|
|
* ----------> S1 |
|
|
* /| |
|
|
* / |S |
|
|
* F/ \_____/
|
|
* /
|
|
* |<-----
|
|
* | \
|
|
* V |S
|
|
* Q2 ---> U----->backtrack
|
|
* | F /
|
|
* S| /
|
|
* V F /
|
|
* S2--/
|
|
*/
|
|
|
|
GreedyLoopState::GreedyLoopState(bool not_at_start) {
|
|
counter_backtrack_trace_.set_backtrack(&label_);
|
|
if (not_at_start) counter_backtrack_trace_.set_at_start(Trace::FALSE_VALUE);
|
|
}
|
|
|
|
void ChoiceNode::AssertGuardsMentionRegisters(Trace* trace) {
|
|
#ifdef DEBUG
|
|
intptr_t choice_count = alternatives_->length();
|
|
for (intptr_t i = 0; i < choice_count - 1; i++) {
|
|
GuardedAlternative alternative = alternatives_->At(i);
|
|
ZoneGrowableArray<Guard*>* guards = alternative.guards();
|
|
intptr_t guard_count = (guards == NULL) ? 0 : guards->length();
|
|
for (intptr_t j = 0; j < guard_count; j++) {
|
|
ASSERT(!trace->mentions_reg(guards->At(j)->reg()));
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
void ChoiceNode::SetUpPreLoad(RegExpCompiler* compiler,
|
|
Trace* current_trace,
|
|
PreloadState* state) {
|
|
if (state->eats_at_least_ == PreloadState::kEatsAtLeastNotYetInitialized) {
|
|
// Save some time by looking at most one machine word ahead.
|
|
state->eats_at_least_ =
|
|
EatsAtLeast(compiler->one_byte() ? 4 : 2, kRecursionBudget,
|
|
current_trace->at_start() == Trace::FALSE_VALUE);
|
|
}
|
|
state->preload_characters_ =
|
|
CalculatePreloadCharacters(compiler, state->eats_at_least_);
|
|
|
|
state->preload_is_current_ =
|
|
(current_trace->characters_preloaded() == state->preload_characters_);
|
|
state->preload_has_checked_bounds_ = state->preload_is_current_;
|
|
}
|
|
|
|
void ChoiceNode::Emit(RegExpCompiler* compiler, Trace* trace) {
|
|
intptr_t choice_count = alternatives_->length();
|
|
|
|
if (choice_count == 1 && alternatives_->At(0).guards() == nullptr) {
|
|
alternatives_->At(0).node()->Emit(compiler, trace);
|
|
return;
|
|
}
|
|
|
|
AssertGuardsMentionRegisters(trace);
|
|
|
|
LimitResult limit_result = LimitVersions(compiler, trace);
|
|
if (limit_result == DONE) return;
|
|
ASSERT(limit_result == CONTINUE);
|
|
|
|
// For loop nodes we already flushed (see LoopChoiceNode::Emit), but for
|
|
// other choice nodes we only flush if we are out of code size budget.
|
|
if (trace->flush_budget() == 0 && trace->actions() != NULL) {
|
|
trace->Flush(compiler, this);
|
|
return;
|
|
}
|
|
|
|
RecursionCheck rc(compiler);
|
|
|
|
PreloadState preload;
|
|
preload.init();
|
|
GreedyLoopState greedy_loop_state(not_at_start());
|
|
|
|
intptr_t text_length =
|
|
GreedyLoopTextLengthForAlternative(&alternatives_->At(0));
|
|
AlternativeGenerationList alt_gens(choice_count);
|
|
|
|
if (choice_count > 1 && text_length != kNodeIsTooComplexForGreedyLoops) {
|
|
trace = EmitGreedyLoop(compiler, trace, &alt_gens, &preload,
|
|
&greedy_loop_state, text_length);
|
|
} else {
|
|
// TODO(erikcorry): Delete this. We don't need this label, but it makes us
|
|
// match the traces produced pre-cleanup.
|
|
BlockLabel second_choice;
|
|
compiler->macro_assembler()->BindBlock(&second_choice);
|
|
|
|
preload.eats_at_least_ = EmitOptimizedUnanchoredSearch(compiler, trace);
|
|
|
|
EmitChoices(compiler, &alt_gens, 0, trace, &preload);
|
|
}
|
|
|
|
// At this point we need to generate slow checks for the alternatives where
|
|
// the quick check was inlined. We can recognize these because the associated
|
|
// label was bound.
|
|
intptr_t new_flush_budget = trace->flush_budget() / choice_count;
|
|
for (intptr_t i = 0; i < choice_count; i++) {
|
|
AlternativeGeneration* alt_gen = alt_gens.at(i);
|
|
Trace new_trace(*trace);
|
|
// If there are actions to be flushed we have to limit how many times
|
|
// they are flushed. Take the budget of the parent trace and distribute
|
|
// it fairly amongst the children.
|
|
if (new_trace.actions() != NULL) {
|
|
new_trace.set_flush_budget(new_flush_budget);
|
|
}
|
|
bool next_expects_preload =
|
|
i == choice_count - 1 ? false : alt_gens.at(i + 1)->expects_preload;
|
|
EmitOutOfLineContinuation(compiler, &new_trace, alternatives_->At(i),
|
|
alt_gen, preload.preload_characters_,
|
|
next_expects_preload);
|
|
}
|
|
}
|
|
|
|
Trace* ChoiceNode::EmitGreedyLoop(RegExpCompiler* compiler,
|
|
Trace* trace,
|
|
AlternativeGenerationList* alt_gens,
|
|
PreloadState* preload,
|
|
GreedyLoopState* greedy_loop_state,
|
|
intptr_t text_length) {
|
|
RegExpMacroAssembler* macro_assembler = compiler->macro_assembler();
|
|
// Here we have special handling for greedy loops containing only text nodes
|
|
// and other simple nodes. These are handled by pushing the current
|
|
// position on the stack and then incrementing the current position each
|
|
// time around the switch. On backtrack we decrement the current position
|
|
// and check it against the pushed value. This avoids pushing backtrack
|
|
// information for each iteration of the loop, which could take up a lot of
|
|
// space.
|
|
ASSERT(trace->stop_node() == NULL);
|
|
macro_assembler->PushCurrentPosition();
|
|
BlockLabel greedy_match_failed;
|
|
Trace greedy_match_trace;
|
|
if (not_at_start()) greedy_match_trace.set_at_start(Trace::FALSE_VALUE);
|
|
greedy_match_trace.set_backtrack(&greedy_match_failed);
|
|
BlockLabel loop_label;
|
|
macro_assembler->BindBlock(&loop_label);
|
|
macro_assembler->CheckPreemption(/*is_backtrack=*/false);
|
|
greedy_match_trace.set_stop_node(this);
|
|
greedy_match_trace.set_loop_label(&loop_label);
|
|
(*alternatives_)[0].node()->Emit(compiler, &greedy_match_trace);
|
|
macro_assembler->BindBlock(&greedy_match_failed);
|
|
|
|
BlockLabel second_choice; // For use in greedy matches.
|
|
macro_assembler->BindBlock(&second_choice);
|
|
|
|
Trace* new_trace = greedy_loop_state->counter_backtrack_trace();
|
|
|
|
EmitChoices(compiler, alt_gens, 1, new_trace, preload);
|
|
|
|
macro_assembler->BindBlock(greedy_loop_state->label());
|
|
// If we have unwound to the bottom then backtrack.
|
|
macro_assembler->CheckGreedyLoop(trace->backtrack());
|
|
// Otherwise try the second priority at an earlier position.
|
|
macro_assembler->AdvanceCurrentPosition(-text_length);
|
|
macro_assembler->GoTo(&second_choice);
|
|
return new_trace;
|
|
}
|
|
|
|
intptr_t ChoiceNode::EmitOptimizedUnanchoredSearch(RegExpCompiler* compiler,
|
|
Trace* trace) {
|
|
intptr_t eats_at_least = PreloadState::kEatsAtLeastNotYetInitialized;
|
|
if (alternatives_->length() != 2) return eats_at_least;
|
|
|
|
GuardedAlternative alt1 = alternatives_->At(1);
|
|
if (alt1.guards() != NULL && alt1.guards()->length() != 0) {
|
|
return eats_at_least;
|
|
}
|
|
RegExpNode* eats_anything_node = alt1.node();
|
|
if (eats_anything_node->GetSuccessorOfOmnivorousTextNode(compiler) != this) {
|
|
return eats_at_least;
|
|
}
|
|
|
|
// Really we should be creating a new trace when we execute this function,
|
|
// but there is no need, because the code it generates cannot backtrack, and
|
|
// we always arrive here with a trivial trace (since it's the entry to a
|
|
// loop. That also implies that there are no preloaded characters, which is
|
|
// good, because it means we won't be violating any assumptions by
|
|
// overwriting those characters with new load instructions.
|
|
ASSERT(trace->is_trivial());
|
|
|
|
RegExpMacroAssembler* macro_assembler = compiler->macro_assembler();
|
|
// At this point we know that we are at a non-greedy loop that will eat
|
|
// any character one at a time. Any non-anchored regexp has such a
|
|
// loop prepended to it in order to find where it starts. We look for
|
|
// a pattern of the form ...abc... where we can look 6 characters ahead
|
|
// and step forwards 3 if the character is not one of abc. Abc need
|
|
// not be atoms, they can be any reasonably limited character class or
|
|
// small alternation.
|
|
BoyerMooreLookahead* bm = bm_info(false);
|
|
if (bm == NULL) {
|
|
eats_at_least = Utils::Minimum(
|
|
kMaxLookaheadForBoyerMoore,
|
|
EatsAtLeast(kMaxLookaheadForBoyerMoore, kRecursionBudget, false));
|
|
if (eats_at_least >= 1) {
|
|
bm = new (Z) BoyerMooreLookahead(eats_at_least, compiler, Z);
|
|
GuardedAlternative alt0 = alternatives_->At(0);
|
|
alt0.node()->FillInBMInfo(0, kRecursionBudget, bm, false);
|
|
}
|
|
}
|
|
if (bm != NULL) {
|
|
bm->EmitSkipInstructions(macro_assembler);
|
|
}
|
|
return eats_at_least;
|
|
}
|
|
|
|
void ChoiceNode::EmitChoices(RegExpCompiler* compiler,
|
|
AlternativeGenerationList* alt_gens,
|
|
intptr_t first_choice,
|
|
Trace* trace,
|
|
PreloadState* preload) {
|
|
RegExpMacroAssembler* macro_assembler = compiler->macro_assembler();
|
|
SetUpPreLoad(compiler, trace, preload);
|
|
|
|
// For now we just call all choices one after the other. The idea ultimately
|
|
// is to use the Dispatch table to try only the relevant ones.
|
|
intptr_t choice_count = alternatives_->length();
|
|
|
|
intptr_t new_flush_budget = trace->flush_budget() / choice_count;
|
|
|
|
for (intptr_t i = first_choice; i < choice_count; i++) {
|
|
bool is_last = i == choice_count - 1;
|
|
bool fall_through_on_failure = !is_last;
|
|
GuardedAlternative alternative = alternatives_->At(i);
|
|
AlternativeGeneration* alt_gen = alt_gens->at(i);
|
|
alt_gen->quick_check_details.set_characters(preload->preload_characters_);
|
|
ZoneGrowableArray<Guard*>* guards = alternative.guards();
|
|
intptr_t guard_count = (guards == NULL) ? 0 : guards->length();
|
|
Trace new_trace(*trace);
|
|
new_trace.set_characters_preloaded(
|
|
preload->preload_is_current_ ? preload->preload_characters_ : 0);
|
|
if (preload->preload_has_checked_bounds_) {
|
|
new_trace.set_bound_checked_up_to(preload->preload_characters_);
|
|
}
|
|
new_trace.quick_check_performed()->Clear();
|
|
if (not_at_start_) new_trace.set_at_start(Trace::FALSE_VALUE);
|
|
if (!is_last) {
|
|
new_trace.set_backtrack(&alt_gen->after);
|
|
}
|
|
alt_gen->expects_preload = preload->preload_is_current_;
|
|
bool generate_full_check_inline = false;
|
|
if (kRegexpOptimization &&
|
|
try_to_emit_quick_check_for_alternative(i == 0) &&
|
|
alternative.node()->EmitQuickCheck(
|
|
compiler, trace, &new_trace, preload->preload_has_checked_bounds_,
|
|
&alt_gen->possible_success, &alt_gen->quick_check_details,
|
|
fall_through_on_failure)) {
|
|
// Quick check was generated for this choice.
|
|
preload->preload_is_current_ = true;
|
|
preload->preload_has_checked_bounds_ = true;
|
|
// If we generated the quick check to fall through on possible success,
|
|
// we now need to generate the full check inline.
|
|
if (!fall_through_on_failure) {
|
|
macro_assembler->BindBlock(&alt_gen->possible_success);
|
|
new_trace.set_quick_check_performed(&alt_gen->quick_check_details);
|
|
new_trace.set_characters_preloaded(preload->preload_characters_);
|
|
new_trace.set_bound_checked_up_to(preload->preload_characters_);
|
|
generate_full_check_inline = true;
|
|
}
|
|
} else if (alt_gen->quick_check_details.cannot_match()) {
|
|
if (!fall_through_on_failure) {
|
|
macro_assembler->GoTo(trace->backtrack());
|
|
}
|
|
continue;
|
|
} else {
|
|
// No quick check was generated. Put the full code here.
|
|
// If this is not the first choice then there could be slow checks from
|
|
// previous cases that go here when they fail. There's no reason to
|
|
// insist that they preload characters since the slow check we are about
|
|
// to generate probably can't use it.
|
|
if (i != first_choice) {
|
|
alt_gen->expects_preload = false;
|
|
new_trace.InvalidateCurrentCharacter();
|
|
}
|
|
generate_full_check_inline = true;
|
|
}
|
|
if (generate_full_check_inline) {
|
|
if (new_trace.actions() != NULL) {
|
|
new_trace.set_flush_budget(new_flush_budget);
|
|
}
|
|
for (intptr_t j = 0; j < guard_count; j++) {
|
|
GenerateGuard(macro_assembler, guards->At(j), &new_trace);
|
|
}
|
|
alternative.node()->Emit(compiler, &new_trace);
|
|
preload->preload_is_current_ = false;
|
|
}
|
|
macro_assembler->BindBlock(&alt_gen->after);
|
|
}
|
|
}
|
|
|
|
void ChoiceNode::EmitOutOfLineContinuation(RegExpCompiler* compiler,
|
|
Trace* trace,
|
|
GuardedAlternative alternative,
|
|
AlternativeGeneration* alt_gen,
|
|
intptr_t preload_characters,
|
|
bool next_expects_preload) {
|
|
if (!alt_gen->possible_success.IsLinked()) return;
|
|
|
|
RegExpMacroAssembler* macro_assembler = compiler->macro_assembler();
|
|
macro_assembler->BindBlock(&alt_gen->possible_success);
|
|
Trace out_of_line_trace(*trace);
|
|
out_of_line_trace.set_characters_preloaded(preload_characters);
|
|
out_of_line_trace.set_quick_check_performed(&alt_gen->quick_check_details);
|
|
if (not_at_start_) out_of_line_trace.set_at_start(Trace::FALSE_VALUE);
|
|
ZoneGrowableArray<Guard*>* guards = alternative.guards();
|
|
intptr_t guard_count = (guards == NULL) ? 0 : guards->length();
|
|
if (next_expects_preload) {
|
|
BlockLabel reload_current_char;
|
|
out_of_line_trace.set_backtrack(&reload_current_char);
|
|
for (intptr_t j = 0; j < guard_count; j++) {
|
|
GenerateGuard(macro_assembler, guards->At(j), &out_of_line_trace);
|
|
}
|
|
alternative.node()->Emit(compiler, &out_of_line_trace);
|
|
macro_assembler->BindBlock(&reload_current_char);
|
|
// Reload the current character, since the next quick check expects that.
|
|
// We don't need to check bounds here because we only get into this
|
|
// code through a quick check which already did the checked load.
|
|
macro_assembler->LoadCurrentCharacter(trace->cp_offset(), NULL, false,
|
|
preload_characters);
|
|
macro_assembler->GoTo(&(alt_gen->after));
|
|
} else {
|
|
out_of_line_trace.set_backtrack(&(alt_gen->after));
|
|
for (intptr_t j = 0; j < guard_count; j++) {
|
|
GenerateGuard(macro_assembler, guards->At(j), &out_of_line_trace);
|
|
}
|
|
alternative.node()->Emit(compiler, &out_of_line_trace);
|
|
}
|
|
}
|
|
|
|
void ActionNode::Emit(RegExpCompiler* compiler, Trace* trace) {
|
|
RegExpMacroAssembler* assembler = compiler->macro_assembler();
|
|
LimitResult limit_result = LimitVersions(compiler, trace);
|
|
if (limit_result == DONE) return;
|
|
ASSERT(limit_result == CONTINUE);
|
|
|
|
RecursionCheck rc(compiler);
|
|
|
|
switch (action_type_) {
|
|
case STORE_POSITION: {
|
|
Trace::DeferredCapture new_capture(data_.u_position_register.reg,
|
|
data_.u_position_register.is_capture,
|
|
trace);
|
|
Trace new_trace = *trace;
|
|
new_trace.add_action(&new_capture);
|
|
on_success()->Emit(compiler, &new_trace);
|
|
break;
|
|
}
|
|
case INCREMENT_REGISTER: {
|
|
Trace::DeferredIncrementRegister new_increment(
|
|
data_.u_increment_register.reg);
|
|
Trace new_trace = *trace;
|
|
new_trace.add_action(&new_increment);
|
|
on_success()->Emit(compiler, &new_trace);
|
|
break;
|
|
}
|
|
case SET_REGISTER: {
|
|
Trace::DeferredSetRegister new_set(data_.u_store_register.reg,
|
|
data_.u_store_register.value);
|
|
Trace new_trace = *trace;
|
|
new_trace.add_action(&new_set);
|
|
on_success()->Emit(compiler, &new_trace);
|
|
break;
|
|
}
|
|
case CLEAR_CAPTURES: {
|
|
Trace::DeferredClearCaptures new_capture(Interval(
|
|
data_.u_clear_captures.range_from, data_.u_clear_captures.range_to));
|
|
Trace new_trace = *trace;
|
|
new_trace.add_action(&new_capture);
|
|
on_success()->Emit(compiler, &new_trace);
|
|
break;
|
|
}
|
|
case BEGIN_SUBMATCH:
|
|
if (!trace->is_trivial()) {
|
|
trace->Flush(compiler, this);
|
|
} else {
|
|
assembler->WriteCurrentPositionToRegister(
|
|
data_.u_submatch.current_position_register, 0);
|
|
assembler->WriteStackPointerToRegister(
|
|
data_.u_submatch.stack_pointer_register);
|
|
on_success()->Emit(compiler, trace);
|
|
}
|
|
break;
|
|
case EMPTY_MATCH_CHECK: {
|
|
intptr_t start_pos_reg = data_.u_empty_match_check.start_register;
|
|
intptr_t stored_pos = 0;
|
|
intptr_t rep_reg = data_.u_empty_match_check.repetition_register;
|
|
bool has_minimum = (rep_reg != RegExpCompiler::kNoRegister);
|
|
bool know_dist = trace->GetStoredPosition(start_pos_reg, &stored_pos);
|
|
if (know_dist && !has_minimum && stored_pos == trace->cp_offset()) {
|
|
// If we know we haven't advanced and there is no minimum we
|
|
// can just backtrack immediately.
|
|
assembler->GoTo(trace->backtrack());
|
|
} else if (know_dist && stored_pos < trace->cp_offset()) {
|
|
// If we know we've advanced we can generate the continuation
|
|
// immediately.
|
|
on_success()->Emit(compiler, trace);
|
|
} else if (!trace->is_trivial()) {
|
|
trace->Flush(compiler, this);
|
|
} else {
|
|
BlockLabel skip_empty_check;
|
|
// If we have a minimum number of repetitions we check the current
|
|
// number first and skip the empty check if it's not enough.
|
|
if (has_minimum) {
|
|
intptr_t limit = data_.u_empty_match_check.repetition_limit;
|
|
assembler->IfRegisterLT(rep_reg, limit, &skip_empty_check);
|
|
}
|
|
// If the match is empty we bail out, otherwise we fall through
|
|
// to the on-success continuation.
|
|
assembler->IfRegisterEqPos(data_.u_empty_match_check.start_register,
|
|
trace->backtrack());
|
|
assembler->BindBlock(&skip_empty_check);
|
|
on_success()->Emit(compiler, trace);
|
|
}
|
|
break;
|
|
}
|
|
case POSITIVE_SUBMATCH_SUCCESS: {
|
|
if (!trace->is_trivial()) {
|
|
trace->Flush(compiler, this);
|
|
return;
|
|
}
|
|
assembler->ReadCurrentPositionFromRegister(
|
|
data_.u_submatch.current_position_register);
|
|
assembler->ReadStackPointerFromRegister(
|
|
data_.u_submatch.stack_pointer_register);
|
|
intptr_t clear_register_count = data_.u_submatch.clear_register_count;
|
|
if (clear_register_count == 0) {
|
|
on_success()->Emit(compiler, trace);
|
|
return;
|
|
}
|
|
intptr_t clear_registers_from = data_.u_submatch.clear_register_from;
|
|
BlockLabel clear_registers_backtrack;
|
|
Trace new_trace = *trace;
|
|
new_trace.set_backtrack(&clear_registers_backtrack);
|
|
on_success()->Emit(compiler, &new_trace);
|
|
|
|
assembler->BindBlock(&clear_registers_backtrack);
|
|
intptr_t clear_registers_to =
|
|
clear_registers_from + clear_register_count - 1;
|
|
assembler->ClearRegisters(clear_registers_from, clear_registers_to);
|
|
|
|
ASSERT(trace->backtrack() == NULL);
|
|
assembler->Backtrack();
|
|
return;
|
|
}
|
|
default:
|
|
UNREACHABLE();
|
|
}
|
|
}
|
|
|
|
void BackReferenceNode::Emit(RegExpCompiler* compiler, Trace* trace) {
|
|
RegExpMacroAssembler* assembler = compiler->macro_assembler();
|
|
if (!trace->is_trivial()) {
|
|
trace->Flush(compiler, this);
|
|
return;
|
|
}
|
|
|
|
LimitResult limit_result = LimitVersions(compiler, trace);
|
|
if (limit_result == DONE) return;
|
|
ASSERT(limit_result == CONTINUE);
|
|
|
|
RecursionCheck rc(compiler);
|
|
|
|
ASSERT(start_reg_ + 1 == end_reg_);
|
|
if (flags_.IgnoreCase()) {
|
|
assembler->CheckNotBackReferenceIgnoreCase(
|
|
start_reg_, read_backward(), flags_.IsUnicode(), trace->backtrack());
|
|
} else {
|
|
assembler->CheckNotBackReference(start_reg_, read_backward(),
|
|
trace->backtrack());
|
|
}
|
|
// We are going to advance backward, so we may end up at the start.
|
|
if (read_backward()) trace->set_at_start(Trace::UNKNOWN);
|
|
|
|
// Check that the back reference does not end inside a surrogate pair.
|
|
if (flags_.IsUnicode() && !compiler->one_byte()) {
|
|
assembler->CheckNotInSurrogatePair(trace->cp_offset(), trace->backtrack());
|
|
}
|
|
|
|
on_success()->Emit(compiler, trace);
|
|
}
|
|
|
|
// -------------------------------------------------------------------
|
|
// Dot/dotty output
|
|
|
|
#ifdef DEBUG
|
|
|
|
class DotPrinter : public NodeVisitor {
|
|
public:
|
|
explicit DotPrinter(bool ignore_case) {}
|
|
void PrintNode(const char* label, RegExpNode* node);
|
|
void Visit(RegExpNode* node);
|
|
void PrintAttributes(RegExpNode* from);
|
|
void PrintOnFailure(RegExpNode* from, RegExpNode* to);
|
|
#define DECLARE_VISIT(Type) virtual void Visit##Type(Type##Node* that);
|
|
FOR_EACH_NODE_TYPE(DECLARE_VISIT)
|
|
#undef DECLARE_VISIT
|
|
};
|
|
|
|
void DotPrinter::PrintNode(const char* label, RegExpNode* node) {
|
|
OS::PrintErr("digraph G {\n graph [label=\"");
|
|
for (intptr_t i = 0; label[i] != '\0'; i++) {
|
|
switch (label[i]) {
|
|
case '\\':
|
|
OS::PrintErr("\\\\");
|
|
break;
|
|
case '"':
|
|
OS::PrintErr("\"");
|
|
break;
|
|
default:
|
|
OS::PrintErr("%c", label[i]);
|
|
break;
|
|
}
|
|
}
|
|
OS::PrintErr("\"];\n");
|
|
Visit(node);
|
|
OS::PrintErr("}\n");
|
|
}
|
|
|
|
void DotPrinter::Visit(RegExpNode* node) {
|
|
if (node->info()->visited) return;
|
|
node->info()->visited = true;
|
|
node->Accept(this);
|
|
}
|
|
|
|
void DotPrinter::PrintOnFailure(RegExpNode* from, RegExpNode* on_failure) {
|
|
OS::PrintErr(" n%p -> n%p [style=dotted];\n", from, on_failure);
|
|
Visit(on_failure);
|
|
}
|
|
|
|
class AttributePrinter : public ValueObject {
|
|
public:
|
|
AttributePrinter() : first_(true) {}
|
|
void PrintSeparator() {
|
|
if (first_) {
|
|
first_ = false;
|
|
} else {
|
|
OS::PrintErr("|");
|
|
}
|
|
}
|
|
void PrintBit(const char* name, bool value) {
|
|
if (!value) return;
|
|
PrintSeparator();
|
|
OS::PrintErr("{%s}", name);
|
|
}
|
|
void PrintPositive(const char* name, intptr_t value) {
|
|
if (value < 0) return;
|
|
PrintSeparator();
|
|
OS::PrintErr("{%s|%" Pd "}", name, value);
|
|
}
|
|
|
|
private:
|
|
bool first_;
|
|
};
|
|
|
|
void DotPrinter::PrintAttributes(RegExpNode* that) {
|
|
OS::PrintErr(
|
|
" a%p [shape=Mrecord, color=grey, fontcolor=grey, "
|
|
"margin=0.1, fontsize=10, label=\"{",
|
|
that);
|
|
AttributePrinter printer;
|
|
NodeInfo* info = that->info();
|
|
printer.PrintBit("NI", info->follows_newline_interest);
|
|
printer.PrintBit("WI", info->follows_word_interest);
|
|
printer.PrintBit("SI", info->follows_start_interest);
|
|
BlockLabel* label = that->label();
|
|
if (label->IsBound()) printer.PrintPositive("@", label->Position());
|
|
OS::PrintErr(
|
|
"}\"];\n"
|
|
" a%p -> n%p [style=dashed, color=grey, arrowhead=none];\n",
|
|
that, that);
|
|
}
|
|
|
|
void DotPrinter::VisitChoice(ChoiceNode* that) {
|
|
OS::PrintErr(" n%p [shape=Mrecord, label=\"?\"];\n", that);
|
|
for (intptr_t i = 0; i < that->alternatives()->length(); i++) {
|
|
GuardedAlternative alt = that->alternatives()->At(i);
|
|
OS::PrintErr(" n%p -> n%p", that, alt.node());
|
|
}
|
|
for (intptr_t i = 0; i < that->alternatives()->length(); i++) {
|
|
GuardedAlternative alt = that->alternatives()->At(i);
|
|
alt.node()->Accept(this);
|
|
}
|
|
}
|
|
|
|
void DotPrinter::VisitText(TextNode* that) {
|
|
OS::PrintErr(" n%p [label=\"", that);
|
|
for (intptr_t i = 0; i < that->elements()->length(); i++) {
|
|
if (i > 0) OS::PrintErr(" ");
|
|
TextElement elm = that->elements()->At(i);
|
|
switch (elm.text_type()) {
|
|
case TextElement::ATOM: {
|
|
ZoneGrowableArray<uint16_t>* data = elm.atom()->data();
|
|
for (intptr_t i = 0; i < data->length(); i++) {
|
|
OS::PrintErr("%c", static_cast<char>(data->At(i)));
|
|
}
|
|
break;
|
|
}
|
|
case TextElement::CHAR_CLASS: {
|
|
RegExpCharacterClass* node = elm.char_class();
|
|
OS::PrintErr("[");
|
|
if (node->is_negated()) OS::PrintErr("^");
|
|
for (intptr_t j = 0; j < node->ranges()->length(); j++) {
|
|
CharacterRange range = node->ranges()->At(j);
|
|
PrintUtf16(range.from());
|
|
OS::PrintErr("-");
|
|
PrintUtf16(range.to());
|
|
}
|
|
OS::PrintErr("]");
|
|
break;
|
|
}
|
|
default:
|
|
UNREACHABLE();
|
|
}
|
|
}
|
|
OS::PrintErr("\", shape=box, peripheries=2];\n");
|
|
PrintAttributes(that);
|
|
OS::PrintErr(" n%p -> n%p;\n", that, that->on_success());
|
|
Visit(that->on_success());
|
|
}
|
|
|
|
void DotPrinter::VisitBackReference(BackReferenceNode* that) {
|
|
OS::PrintErr(" n%p [label=\"$%" Pd "..$%" Pd "\", shape=doubleoctagon];\n",
|
|
that, that->start_register(), that->end_register());
|
|
PrintAttributes(that);
|
|
OS::PrintErr(" n%p -> n%p;\n", that, that->on_success());
|
|
Visit(that->on_success());
|
|
}
|
|
|
|
void DotPrinter::VisitEnd(EndNode* that) {
|
|
OS::PrintErr(" n%p [style=bold, shape=point];\n", that);
|
|
PrintAttributes(that);
|
|
}
|
|
|
|
void DotPrinter::VisitAssertion(AssertionNode* that) {
|
|
OS::PrintErr(" n%p [", that);
|
|
switch (that->assertion_type()) {
|
|
case AssertionNode::AT_END:
|
|
OS::PrintErr("label=\"$\", shape=septagon");
|
|
break;
|
|
case AssertionNode::AT_START:
|
|
OS::PrintErr("label=\"^\", shape=septagon");
|
|
break;
|
|
case AssertionNode::AT_BOUNDARY:
|
|
OS::PrintErr("label=\"\\b\", shape=septagon");
|
|
break;
|
|
case AssertionNode::AT_NON_BOUNDARY:
|
|
OS::PrintErr("label=\"\\B\", shape=septagon");
|
|
break;
|
|
case AssertionNode::AFTER_NEWLINE:
|
|
OS::PrintErr("label=\"(?<=\\n)\", shape=septagon");
|
|
break;
|
|
}
|
|
OS::PrintErr("];\n");
|
|
PrintAttributes(that);
|
|
RegExpNode* successor = that->on_success();
|
|
OS::PrintErr(" n%p -> n%p;\n", that, successor);
|
|
Visit(successor);
|
|
}
|
|
|
|
void DotPrinter::VisitAction(ActionNode* that) {
|
|
OS::PrintErr(" n%p [", that);
|
|
switch (that->action_type_) {
|
|
case ActionNode::SET_REGISTER:
|
|
OS::PrintErr("label=\"$%" Pd ":=%" Pd "\", shape=octagon",
|
|
that->data_.u_store_register.reg,
|
|
that->data_.u_store_register.value);
|
|
break;
|
|
case ActionNode::INCREMENT_REGISTER:
|
|
OS::PrintErr("label=\"$%" Pd "++\", shape=octagon",
|
|
that->data_.u_increment_register.reg);
|
|
break;
|
|
case ActionNode::STORE_POSITION:
|
|
OS::PrintErr("label=\"$%" Pd ":=$pos\", shape=octagon",
|
|
that->data_.u_position_register.reg);
|
|
break;
|
|
case ActionNode::BEGIN_SUBMATCH:
|
|
OS::PrintErr("label=\"$%" Pd ":=$pos,begin\", shape=septagon",
|
|
that->data_.u_submatch.current_position_register);
|
|
break;
|
|
case ActionNode::POSITIVE_SUBMATCH_SUCCESS:
|
|
OS::PrintErr("label=\"escape\", shape=septagon");
|
|
break;
|
|
case ActionNode::EMPTY_MATCH_CHECK:
|
|
OS::PrintErr("label=\"$%" Pd "=$pos?,$%" Pd "<%" Pd "?\", shape=septagon",
|
|
that->data_.u_empty_match_check.start_register,
|
|
that->data_.u_empty_match_check.repetition_register,
|
|
that->data_.u_empty_match_check.repetition_limit);
|
|
break;
|
|
case ActionNode::CLEAR_CAPTURES: {
|
|
OS::PrintErr("label=\"clear $%" Pd " to $%" Pd "\", shape=septagon",
|
|
that->data_.u_clear_captures.range_from,
|
|
that->data_.u_clear_captures.range_to);
|
|
break;
|
|
}
|
|
}
|
|
OS::PrintErr("];\n");
|
|
PrintAttributes(that);
|
|
RegExpNode* successor = that->on_success();
|
|
OS::PrintErr(" n%p -> n%p;\n", that, successor);
|
|
Visit(successor);
|
|
}
|
|
|
|
void RegExpEngine::DotPrint(const char* label,
|
|
RegExpNode* node,
|
|
bool ignore_case) {
|
|
DotPrinter printer(ignore_case);
|
|
printer.PrintNode(label, node);
|
|
}
|
|
|
|
#endif // DEBUG
|
|
|
|
// -------------------------------------------------------------------
|
|
// Tree to graph conversion
|
|
|
|
// The zone in which we allocate graph nodes.
|
|
#define OZ (on_success->zone())
|
|
|
|
RegExpNode* RegExpAtom::ToNode(RegExpCompiler* compiler,
|
|
RegExpNode* on_success) {
|
|
ZoneGrowableArray<TextElement>* elms =
|
|
new (OZ) ZoneGrowableArray<TextElement>(1);
|
|
elms->Add(TextElement::Atom(this));
|
|
return new (OZ) TextNode(elms, compiler->read_backward(), on_success);
|
|
}
|
|
|
|
RegExpNode* RegExpText::ToNode(RegExpCompiler* compiler,
|
|
RegExpNode* on_success) {
|
|
ZoneGrowableArray<TextElement>* elms =
|
|
new (OZ) ZoneGrowableArray<TextElement>(1);
|
|
for (intptr_t i = 0; i < elements()->length(); i++) {
|
|
elms->Add(elements()->At(i));
|
|
}
|
|
return new (OZ) TextNode(elms, compiler->read_backward(), on_success);
|
|
}
|
|
|
|
static bool CompareInverseRanges(ZoneGrowableArray<CharacterRange>* ranges,
|
|
const int32_t* special_class,
|
|
intptr_t length) {
|
|
length--; // Remove final kRangeEndMarker.
|
|
ASSERT(special_class[length] == kRangeEndMarker);
|
|
ASSERT(ranges->length() != 0);
|
|
ASSERT(length != 0);
|
|
ASSERT(special_class[0] != 0);
|
|
if (ranges->length() != (length >> 1) + 1) {
|
|
return false;
|
|
}
|
|
CharacterRange range = ranges->At(0);
|
|
if (range.from() != 0) {
|
|
return false;
|
|
}
|
|
for (intptr_t i = 0; i < length; i += 2) {
|
|
if (special_class[i] != (range.to() + 1)) {
|
|
return false;
|
|
}
|
|
range = ranges->At((i >> 1) + 1);
|
|
if (special_class[i + 1] != range.from()) {
|
|
return false;
|
|
}
|
|
}
|
|
if (range.to() != Utf::kMaxCodePoint) {
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
static bool CompareRanges(ZoneGrowableArray<CharacterRange>* ranges,
|
|
const int32_t* special_class,
|
|
intptr_t length) {
|
|
length--; // Remove final kRangeEndMarker.
|
|
ASSERT(special_class[length] == kRangeEndMarker);
|
|
if (ranges->length() * 2 != length) {
|
|
return false;
|
|
}
|
|
for (intptr_t i = 0; i < length; i += 2) {
|
|
CharacterRange range = ranges->At(i >> 1);
|
|
if (range.from() != special_class[i] ||
|
|
range.to() != special_class[i + 1] - 1) {
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bool RegExpCharacterClass::is_standard() {
|
|
// TODO(lrn): Remove need for this function, by not throwing away information
|
|
// along the way.
|
|
if (is_negated()) {
|
|
return false;
|
|
}
|
|
if (set_.is_standard()) {
|
|
return true;
|
|
}
|
|
if (CompareRanges(set_.ranges(), kSpaceRanges, kSpaceRangeCount)) {
|
|
set_.set_standard_set_type('s');
|
|
return true;
|
|
}
|
|
if (CompareInverseRanges(set_.ranges(), kSpaceRanges, kSpaceRangeCount)) {
|
|
set_.set_standard_set_type('S');
|
|
return true;
|
|
}
|
|
if (CompareInverseRanges(set_.ranges(), kLineTerminatorRanges,
|
|
kLineTerminatorRangeCount)) {
|
|
set_.set_standard_set_type('.');
|
|
return true;
|
|
}
|
|
if (CompareRanges(set_.ranges(), kLineTerminatorRanges,
|
|
kLineTerminatorRangeCount)) {
|
|
set_.set_standard_set_type('n');
|
|
return true;
|
|
}
|
|
if (CompareRanges(set_.ranges(), kWordRanges, kWordRangeCount)) {
|
|
set_.set_standard_set_type('w');
|
|
return true;
|
|
}
|
|
if (CompareInverseRanges(set_.ranges(), kWordRanges, kWordRangeCount)) {
|
|
set_.set_standard_set_type('W');
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
UnicodeRangeSplitter::UnicodeRangeSplitter(
|
|
Zone* zone,
|
|
ZoneGrowableArray<CharacterRange>* base)
|
|
: zone_(zone),
|
|
table_(zone),
|
|
bmp_(nullptr),
|
|
lead_surrogates_(nullptr),
|
|
trail_surrogates_(nullptr),
|
|
non_bmp_(nullptr) {
|
|
// The unicode range splitter categorizes given character ranges into:
|
|
// - Code points from the BMP representable by one code unit.
|
|
// - Code points outside the BMP that need to be split into surrogate pairs.
|
|
// - Lone lead surrogates.
|
|
// - Lone trail surrogates.
|
|
// Lone surrogates are valid code points, even though no actual characters.
|
|
// They require special matching to make sure we do not split surrogate pairs.
|
|
// We use the dispatch table to accomplish this. The base range is split up
|
|
// by the table by the overlay ranges, and the Call callback is used to
|
|
// filter and collect ranges for each category.
|
|
for (intptr_t i = 0; i < base->length(); i++) {
|
|
table_.AddRange(base->At(i), kBase, zone_);
|
|
}
|
|
// Add overlay ranges.
|
|
table_.AddRange(CharacterRange::Range(0, Utf16::kLeadSurrogateStart - 1),
|
|
kBmpCodePoints, zone_);
|
|
table_.AddRange(CharacterRange::Range(Utf16::kLeadSurrogateStart,
|
|
Utf16::kLeadSurrogateEnd),
|
|
kLeadSurrogates, zone_);
|
|
table_.AddRange(CharacterRange::Range(Utf16::kTrailSurrogateStart,
|
|
Utf16::kTrailSurrogateEnd),
|
|
kTrailSurrogates, zone_);
|
|
table_.AddRange(
|
|
CharacterRange::Range(Utf16::kTrailSurrogateEnd + 1, Utf16::kMaxCodeUnit),
|
|
kBmpCodePoints, zone_);
|
|
table_.AddRange(
|
|
CharacterRange::Range(Utf16::kMaxCodeUnit + 1, Utf::kMaxCodePoint),
|
|
kNonBmpCodePoints, zone_);
|
|
table_.ForEach(this);
|
|
}
|
|
|
|
void UnicodeRangeSplitter::Call(uint32_t from, DispatchTable::Entry entry) {
|
|
OutSet* outset = entry.out_set();
|
|
if (!outset->Get(kBase)) return;
|
|
ZoneGrowableArray<CharacterRange>** target = nullptr;
|
|
if (outset->Get(kBmpCodePoints)) {
|
|
target = &bmp_;
|
|
} else if (outset->Get(kLeadSurrogates)) {
|
|
target = &lead_surrogates_;
|
|
} else if (outset->Get(kTrailSurrogates)) {
|
|
target = &trail_surrogates_;
|
|
} else {
|
|
ASSERT(outset->Get(kNonBmpCodePoints));
|
|
target = &non_bmp_;
|
|
}
|
|
if (*target == nullptr) {
|
|
*target = new (zone_) ZoneGrowableArray<CharacterRange>(2);
|
|
}
|
|
(*target)->Add(CharacterRange::Range(entry.from(), entry.to()));
|
|
}
|
|
|
|
void AddBmpCharacters(RegExpCompiler* compiler,
|
|
ChoiceNode* result,
|
|
RegExpNode* on_success,
|
|
UnicodeRangeSplitter* splitter) {
|
|
ZoneGrowableArray<CharacterRange>* bmp = splitter->bmp();
|
|
if (bmp == nullptr) return;
|
|
result->AddAlternative(GuardedAlternative(TextNode::CreateForCharacterRanges(
|
|
bmp, compiler->read_backward(), on_success, RegExpFlags())));
|
|
}
|
|
|
|
void AddNonBmpSurrogatePairs(RegExpCompiler* compiler,
|
|
ChoiceNode* result,
|
|
RegExpNode* on_success,
|
|
UnicodeRangeSplitter* splitter) {
|
|
ZoneGrowableArray<CharacterRange>* non_bmp = splitter->non_bmp();
|
|
if (non_bmp == nullptr) return;
|
|
ASSERT(!compiler->one_byte());
|
|
CharacterRange::Canonicalize(non_bmp);
|
|
for (int i = 0; i < non_bmp->length(); i++) {
|
|
// Match surrogate pair.
|
|
// E.g. [\u10005-\u11005] becomes
|
|
// \ud800[\udc05-\udfff]|
|
|
// [\ud801-\ud803][\udc00-\udfff]|
|
|
// \ud804[\udc00-\udc05]
|
|
uint32_t from = non_bmp->At(i).from();
|
|
uint32_t to = non_bmp->At(i).to();
|
|
uint16_t from_points[2];
|
|
Utf16::Encode(from, from_points);
|
|
uint16_t to_points[2];
|
|
Utf16::Encode(to, to_points);
|
|
if (from_points[0] == to_points[0]) {
|
|
// The lead surrogate is the same.
|
|
result->AddAlternative(
|
|
GuardedAlternative(TextNode::CreateForSurrogatePair(
|
|
CharacterRange::Singleton(from_points[0]),
|
|
CharacterRange::Range(from_points[1], to_points[1]),
|
|
compiler->read_backward(), on_success, RegExpFlags())));
|
|
} else {
|
|
if (from_points[1] != Utf16::kTrailSurrogateStart) {
|
|
// Add [from_l][from_t-\udfff]
|
|
result->AddAlternative(
|
|
GuardedAlternative(TextNode::CreateForSurrogatePair(
|
|
CharacterRange::Singleton(from_points[0]),
|
|
CharacterRange::Range(from_points[1],
|
|
Utf16::kTrailSurrogateEnd),
|
|
compiler->read_backward(), on_success, RegExpFlags())));
|
|
from_points[0]++;
|
|
}
|
|
if (to_points[1] != Utf16::kTrailSurrogateEnd) {
|
|
// Add [to_l][\udc00-to_t]
|
|
result->AddAlternative(
|
|
GuardedAlternative(TextNode::CreateForSurrogatePair(
|
|
CharacterRange::Singleton(to_points[0]),
|
|
CharacterRange::Range(Utf16::kTrailSurrogateStart,
|
|
to_points[1]),
|
|
compiler->read_backward(), on_success, RegExpFlags())));
|
|
to_points[0]--;
|
|
}
|
|
if (from_points[0] <= to_points[0]) {
|
|
// Add [from_l-to_l][\udc00-\udfff]
|
|
result->AddAlternative(
|
|
GuardedAlternative(TextNode::CreateForSurrogatePair(
|
|
CharacterRange::Range(from_points[0], to_points[0]),
|
|
CharacterRange::Range(Utf16::kTrailSurrogateStart,
|
|
Utf16::kTrailSurrogateEnd),
|
|
compiler->read_backward(), on_success, RegExpFlags())));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
RegExpNode* NegativeLookaroundAgainstReadDirectionAndMatch(
|
|
RegExpCompiler* compiler,
|
|
ZoneGrowableArray<CharacterRange>* lookbehind,
|
|
ZoneGrowableArray<CharacterRange>* match,
|
|
RegExpNode* on_success,
|
|
bool read_backward,
|
|
RegExpFlags flags) {
|
|
RegExpNode* match_node = TextNode::CreateForCharacterRanges(
|
|
match, read_backward, on_success, flags);
|
|
int stack_register = compiler->UnicodeLookaroundStackRegister();
|
|
int position_register = compiler->UnicodeLookaroundPositionRegister();
|
|
RegExpLookaround::Builder lookaround(false, match_node, stack_register,
|
|
position_register);
|
|
RegExpNode* negative_match = TextNode::CreateForCharacterRanges(
|
|
lookbehind, !read_backward, lookaround.on_match_success(), flags);
|
|
return lookaround.ForMatch(negative_match);
|
|
}
|
|
|
|
RegExpNode* MatchAndNegativeLookaroundInReadDirection(
|
|
RegExpCompiler* compiler,
|
|
ZoneGrowableArray<CharacterRange>* match,
|
|
ZoneGrowableArray<CharacterRange>* lookahead,
|
|
RegExpNode* on_success,
|
|
bool read_backward,
|
|
RegExpFlags flags) {
|
|
int stack_register = compiler->UnicodeLookaroundStackRegister();
|
|
int position_register = compiler->UnicodeLookaroundPositionRegister();
|
|
RegExpLookaround::Builder lookaround(false, on_success, stack_register,
|
|
position_register);
|
|
RegExpNode* negative_match = TextNode::CreateForCharacterRanges(
|
|
lookahead, read_backward, lookaround.on_match_success(), flags);
|
|
return TextNode::CreateForCharacterRanges(
|
|
match, read_backward, lookaround.ForMatch(negative_match), flags);
|
|
}
|
|
|
|
void AddLoneLeadSurrogates(RegExpCompiler* compiler,
|
|
ChoiceNode* result,
|
|
RegExpNode* on_success,
|
|
UnicodeRangeSplitter* splitter) {
|
|
auto lead_surrogates = splitter->lead_surrogates();
|
|
if (lead_surrogates == nullptr) return;
|
|
// E.g. \ud801 becomes \ud801(?![\udc00-\udfff]).
|
|
auto trail_surrogates = CharacterRange::List(
|
|
on_success->zone(), CharacterRange::Range(Utf16::kTrailSurrogateStart,
|
|
Utf16::kTrailSurrogateEnd));
|
|
|
|
RegExpNode* match;
|
|
if (compiler->read_backward()) {
|
|
// Reading backward. Assert that reading forward, there is no trail
|
|
// surrogate, and then backward match the lead surrogate.
|
|
match = NegativeLookaroundAgainstReadDirectionAndMatch(
|
|
compiler, trail_surrogates, lead_surrogates, on_success, true,
|
|
RegExpFlags());
|
|
} else {
|
|
// Reading forward. Forward match the lead surrogate and assert that
|
|
// no trail surrogate follows.
|
|
match = MatchAndNegativeLookaroundInReadDirection(
|
|
compiler, lead_surrogates, trail_surrogates, on_success, false,
|
|
RegExpFlags());
|
|
}
|
|
result->AddAlternative(GuardedAlternative(match));
|
|
}
|
|
|
|
void AddLoneTrailSurrogates(RegExpCompiler* compiler,
|
|
ChoiceNode* result,
|
|
RegExpNode* on_success,
|
|
UnicodeRangeSplitter* splitter) {
|
|
auto trail_surrogates = splitter->trail_surrogates();
|
|
if (trail_surrogates == nullptr) return;
|
|
// E.g. \udc01 becomes (?<![\ud800-\udbff])\udc01
|
|
auto lead_surrogates = CharacterRange::List(
|
|
on_success->zone(), CharacterRange::Range(Utf16::kLeadSurrogateStart,
|
|
Utf16::kLeadSurrogateEnd));
|
|
|
|
RegExpNode* match;
|
|
if (compiler->read_backward()) {
|
|
// Reading backward. Backward match the trail surrogate and assert that no
|
|
// lead surrogate precedes it.
|
|
match = MatchAndNegativeLookaroundInReadDirection(
|
|
compiler, trail_surrogates, lead_surrogates, on_success, true,
|
|
RegExpFlags());
|
|
} else {
|
|
// Reading forward. Assert that reading backward, there is no lead
|
|
// surrogate, and then forward match the trail surrogate.
|
|
match = NegativeLookaroundAgainstReadDirectionAndMatch(
|
|
compiler, lead_surrogates, trail_surrogates, on_success, false,
|
|
RegExpFlags());
|
|
}
|
|
result->AddAlternative(GuardedAlternative(match));
|
|
}
|
|
|
|
RegExpNode* UnanchoredAdvance(RegExpCompiler* compiler,
|
|
RegExpNode* on_success) {
|
|
// This implements ES2015 21.2.5.2.3, AdvanceStringIndex.
|
|
ASSERT(!compiler->read_backward());
|
|
// Advance any character. If the character happens to be a lead surrogate and
|
|
// we advanced into the middle of a surrogate pair, it will work out, as
|
|
// nothing will match from there. We will have to advance again, consuming
|
|
// the associated trail surrogate.
|
|
auto range = CharacterRange::List(
|
|
on_success->zone(), CharacterRange::Range(0, Utf16::kMaxCodeUnit));
|
|
return TextNode::CreateForCharacterRanges(range, false, on_success,
|
|
RegExpFlags());
|
|
}
|
|
|
|
void AddUnicodeCaseEquivalents(ZoneGrowableArray<CharacterRange>* ranges) {
|
|
ASSERT(CharacterRange::IsCanonical(ranges));
|
|
|
|
// Micro-optimization to avoid passing large ranges to UnicodeSet::closeOver.
|
|
// See also https://crbug.com/v8/6727.
|
|
// TODO(sstrickl): This only covers the special case of the {0,0x10FFFF}
|
|
// range, which we use frequently internally. But large ranges can also easily
|
|
// be created by the user. We might want to have a more general caching
|
|
// mechanism for such ranges.
|
|
if (ranges->length() == 1 && ranges->At(0).IsEverything(Utf::kMaxCodePoint)) {
|
|
return;
|
|
}
|
|
|
|
icu::UnicodeSet set;
|
|
for (int i = 0; i < ranges->length(); i++) {
|
|
set.add(ranges->At(i).from(), ranges->At(i).to());
|
|
}
|
|
ranges->Clear();
|
|
set.closeOver(USET_CASE_INSENSITIVE);
|
|
// Full case mapping map single characters to multiple characters.
|
|
// Those are represented as strings in the set. Remove them so that
|
|
// we end up with only simple and common case mappings.
|
|
set.removeAllStrings();
|
|
for (int i = 0; i < set.getRangeCount(); i++) {
|
|
ranges->Add(
|
|
CharacterRange::Range(set.getRangeStart(i), set.getRangeEnd(i)));
|
|
}
|
|
// No errors and everything we collected have been ranges.
|
|
CharacterRange::Canonicalize(ranges);
|
|
}
|
|
|
|
RegExpNode* RegExpCharacterClass::ToNode(RegExpCompiler* compiler,
|
|
RegExpNode* on_success) {
|
|
set_.Canonicalize();
|
|
ZoneGrowableArray<CharacterRange>* ranges = this->ranges();
|
|
if (flags_.NeedsUnicodeCaseEquivalents()) {
|
|
AddUnicodeCaseEquivalents(ranges);
|
|
}
|
|
if (flags_.IsUnicode() && !compiler->one_byte() &&
|
|
!contains_split_surrogate()) {
|
|
if (is_negated()) {
|
|
ZoneGrowableArray<CharacterRange>* negated =
|
|
new ZoneGrowableArray<CharacterRange>(2);
|
|
CharacterRange::Negate(ranges, negated);
|
|
ranges = negated;
|
|
}
|
|
if (ranges->length() == 0) {
|
|
RegExpCharacterClass* fail =
|
|
new RegExpCharacterClass(ranges, RegExpFlags());
|
|
return new TextNode(fail, compiler->read_backward(), on_success);
|
|
}
|
|
if (standard_type() == '*') {
|
|
return UnanchoredAdvance(compiler, on_success);
|
|
} else {
|
|
ChoiceNode* result = new (OZ) ChoiceNode(2, OZ);
|
|
UnicodeRangeSplitter splitter(OZ, ranges);
|
|
AddBmpCharacters(compiler, result, on_success, &splitter);
|
|
AddNonBmpSurrogatePairs(compiler, result, on_success, &splitter);
|
|
AddLoneLeadSurrogates(compiler, result, on_success, &splitter);
|
|
AddLoneTrailSurrogates(compiler, result, on_success, &splitter);
|
|
return result;
|
|
}
|
|
} else {
|
|
return new TextNode(this, compiler->read_backward(), on_success);
|
|
}
|
|
return new (OZ) TextNode(this, compiler->read_backward(), on_success);
|
|
}
|
|
|
|
RegExpNode* RegExpDisjunction::ToNode(RegExpCompiler* compiler,
|
|
RegExpNode* on_success) {
|
|
ZoneGrowableArray<RegExpTree*>* alternatives = this->alternatives();
|
|
intptr_t length = alternatives->length();
|
|
ChoiceNode* result = new (OZ) ChoiceNode(length, OZ);
|
|
for (intptr_t i = 0; i < length; i++) {
|
|
GuardedAlternative alternative(
|
|
alternatives->At(i)->ToNode(compiler, on_success));
|
|
result->AddAlternative(alternative);
|
|
}
|
|
return result;
|
|
}
|
|
|
|
RegExpNode* RegExpQuantifier::ToNode(RegExpCompiler* compiler,
|
|
RegExpNode* on_success) {
|
|
return ToNode(min(), max(), is_greedy(), body(), compiler, on_success);
|
|
}
|
|
|
|
// Scoped object to keep track of how much we unroll quantifier loops in the
|
|
// regexp graph generator.
|
|
class RegExpExpansionLimiter : public ValueObject {
|
|
public:
|
|
static const intptr_t kMaxExpansionFactor = 6;
|
|
RegExpExpansionLimiter(RegExpCompiler* compiler, intptr_t factor)
|
|
: compiler_(compiler),
|
|
saved_expansion_factor_(compiler->current_expansion_factor()),
|
|
ok_to_expand_(saved_expansion_factor_ <= kMaxExpansionFactor) {
|
|
ASSERT(factor > 0);
|
|
if (ok_to_expand_) {
|
|
if (factor > kMaxExpansionFactor) {
|
|
// Avoid integer overflow of the current expansion factor.
|
|
ok_to_expand_ = false;
|
|
compiler->set_current_expansion_factor(kMaxExpansionFactor + 1);
|
|
} else {
|
|
intptr_t new_factor = saved_expansion_factor_ * factor;
|
|
ok_to_expand_ = (new_factor <= kMaxExpansionFactor);
|
|
compiler->set_current_expansion_factor(new_factor);
|
|
}
|
|
}
|
|
}
|
|
|
|
~RegExpExpansionLimiter() {
|
|
compiler_->set_current_expansion_factor(saved_expansion_factor_);
|
|
}
|
|
|
|
bool ok_to_expand() { return ok_to_expand_; }
|
|
|
|
private:
|
|
RegExpCompiler* compiler_;
|
|
intptr_t saved_expansion_factor_;
|
|
bool ok_to_expand_;
|
|
|
|
DISALLOW_IMPLICIT_CONSTRUCTORS(RegExpExpansionLimiter);
|
|
};
|
|
|
|
RegExpNode* RegExpQuantifier::ToNode(intptr_t min,
|
|
intptr_t max,
|
|
bool is_greedy,
|
|
RegExpTree* body,
|
|
RegExpCompiler* compiler,
|
|
RegExpNode* on_success,
|
|
bool not_at_start) {
|
|
// x{f, t} becomes this:
|
|
//
|
|
// (r++)<-.
|
|
// | `
|
|
// | (x)
|
|
// v ^
|
|
// (r=0)-->(?)---/ [if r < t]
|
|
// |
|
|
// [if r >= f] \----> ...
|
|
//
|
|
|
|
// 15.10.2.5 RepeatMatcher algorithm.
|
|
// The parser has already eliminated the case where max is 0. In the case
|
|
// where max_match is zero the parser has removed the quantifier if min was
|
|
// > 0 and removed the atom if min was 0. See AddQuantifierToAtom.
|
|
|
|
// If we know that we cannot match zero length then things are a little
|
|
// simpler since we don't need to make the special zero length match check
|
|
// from step 2.1. If the min and max are small we can unroll a little in
|
|
// this case.
|
|
// Unroll (foo)+ and (foo){3,}
|
|
static const intptr_t kMaxUnrolledMinMatches = 3;
|
|
// Unroll (foo)? and (foo){x,3}
|
|
static const intptr_t kMaxUnrolledMaxMatches = 3;
|
|
if (max == 0) return on_success; // This can happen due to recursion.
|
|
bool body_can_be_empty = (body->min_match() == 0);
|
|
intptr_t body_start_reg = RegExpCompiler::kNoRegister;
|
|
Interval capture_registers = body->CaptureRegisters();
|
|
bool needs_capture_clearing = !capture_registers.is_empty();
|
|
Zone* zone = compiler->zone();
|
|
|
|
if (body_can_be_empty) {
|
|
body_start_reg = compiler->AllocateRegister();
|
|
} else if (kRegexpOptimization && !needs_capture_clearing) {
|
|
// Only unroll if there are no captures and the body can't be
|
|
// empty.
|
|
{
|
|
RegExpExpansionLimiter limiter(compiler, min + ((max != min) ? 1 : 0));
|
|
if (min > 0 && min <= kMaxUnrolledMinMatches && limiter.ok_to_expand()) {
|
|
intptr_t new_max = (max == kInfinity) ? max : max - min;
|
|
// Recurse once to get the loop or optional matches after the fixed
|
|
// ones.
|
|
RegExpNode* answer =
|
|
ToNode(0, new_max, is_greedy, body, compiler, on_success, true);
|
|
// Unroll the forced matches from 0 to min. This can cause chains of
|
|
// TextNodes (which the parser does not generate). These should be
|
|
// combined if it turns out they hinder good code generation.
|
|
for (intptr_t i = 0; i < min; i++) {
|
|
answer = body->ToNode(compiler, answer);
|
|
}
|
|
return answer;
|
|
}
|
|
}
|
|
if (max <= kMaxUnrolledMaxMatches && min == 0) {
|
|
ASSERT(max > 0); // Due to the 'if' above.
|
|
RegExpExpansionLimiter limiter(compiler, max);
|
|
if (limiter.ok_to_expand()) {
|
|
// Unroll the optional matches up to max.
|
|
RegExpNode* answer = on_success;
|
|
for (intptr_t i = 0; i < max; i++) {
|
|
ChoiceNode* alternation = new (zone) ChoiceNode(2, zone);
|
|
if (is_greedy) {
|
|
alternation->AddAlternative(
|
|
GuardedAlternative(body->ToNode(compiler, answer)));
|
|
alternation->AddAlternative(GuardedAlternative(on_success));
|
|
} else {
|
|
alternation->AddAlternative(GuardedAlternative(on_success));
|
|
alternation->AddAlternative(
|
|
GuardedAlternative(body->ToNode(compiler, answer)));
|
|
}
|
|
answer = alternation;
|
|
if (not_at_start && !compiler->read_backward()) {
|
|
alternation->set_not_at_start();
|
|
}
|
|
}
|
|
return answer;
|
|
}
|
|
}
|
|
}
|
|
bool has_min = min > 0;
|
|
bool has_max = max < RegExpTree::kInfinity;
|
|
bool needs_counter = has_min || has_max;
|
|
intptr_t reg_ctr = needs_counter ? compiler->AllocateRegister()
|
|
: RegExpCompiler::kNoRegister;
|
|
LoopChoiceNode* center = new (zone)
|
|
LoopChoiceNode(body->min_match() == 0, compiler->read_backward(), zone);
|
|
if (not_at_start && !compiler->read_backward()) center->set_not_at_start();
|
|
RegExpNode* loop_return =
|
|
needs_counter ? static_cast<RegExpNode*>(
|
|
ActionNode::IncrementRegister(reg_ctr, center))
|
|
: static_cast<RegExpNode*>(center);
|
|
if (body_can_be_empty) {
|
|
// If the body can be empty we need to check if it was and then
|
|
// backtrack.
|
|
loop_return =
|
|
ActionNode::EmptyMatchCheck(body_start_reg, reg_ctr, min, loop_return);
|
|
}
|
|
RegExpNode* body_node = body->ToNode(compiler, loop_return);
|
|
if (body_can_be_empty) {
|
|
// If the body can be empty we need to store the start position
|
|
// so we can bail out if it was empty.
|
|
body_node = ActionNode::StorePosition(body_start_reg, false, body_node);
|
|
}
|
|
if (needs_capture_clearing) {
|
|
// Before entering the body of this loop we need to clear captures.
|
|
body_node = ActionNode::ClearCaptures(capture_registers, body_node);
|
|
}
|
|
GuardedAlternative body_alt(body_node);
|
|
if (has_max) {
|
|
Guard* body_guard = new (zone) Guard(reg_ctr, Guard::LT, max);
|
|
body_alt.AddGuard(body_guard, zone);
|
|
}
|
|
GuardedAlternative rest_alt(on_success);
|
|
if (has_min) {
|
|
Guard* rest_guard = new (zone) Guard(reg_ctr, Guard::GEQ, min);
|
|
rest_alt.AddGuard(rest_guard, zone);
|
|
}
|
|
if (is_greedy) {
|
|
center->AddLoopAlternative(body_alt);
|
|
center->AddContinueAlternative(rest_alt);
|
|
} else {
|
|
center->AddContinueAlternative(rest_alt);
|
|
center->AddLoopAlternative(body_alt);
|
|
}
|
|
if (needs_counter) {
|
|
return ActionNode::SetRegister(reg_ctr, 0, center);
|
|
} else {
|
|
return center;
|
|
}
|
|
}
|
|
|
|
namespace {
|
|
// Desugar \b to (?<=\w)(?=\W)|(?<=\W)(?=\w) and
|
|
// \B to (?<=\w)(?=\w)|(?<=\W)(?=\W)
|
|
RegExpNode* BoundaryAssertionAsLookaround(RegExpCompiler* compiler,
|
|
RegExpNode* on_success,
|
|
RegExpAssertion::AssertionType type,
|
|
RegExpFlags flags) {
|
|
ASSERT(flags.NeedsUnicodeCaseEquivalents());
|
|
ZoneGrowableArray<CharacterRange>* word_range =
|
|
new ZoneGrowableArray<CharacterRange>(2);
|
|
CharacterRange::AddClassEscape('w', word_range, true);
|
|
int stack_register = compiler->UnicodeLookaroundStackRegister();
|
|
int position_register = compiler->UnicodeLookaroundPositionRegister();
|
|
ChoiceNode* result = new (OZ) ChoiceNode(2, OZ);
|
|
// Add two choices. The (non-)boundary could start with a word or
|
|
// a non-word-character.
|
|
for (int i = 0; i < 2; i++) {
|
|
bool lookbehind_for_word = i == 0;
|
|
bool lookahead_for_word =
|
|
(type == RegExpAssertion::BOUNDARY) ^ lookbehind_for_word;
|
|
// Look to the left.
|
|
RegExpLookaround::Builder lookbehind(lookbehind_for_word, on_success,
|
|
stack_register, position_register);
|
|
RegExpNode* backward = TextNode::CreateForCharacterRanges(
|
|
word_range, true, lookbehind.on_match_success(), flags);
|
|
// Look to the right.
|
|
RegExpLookaround::Builder lookahead(lookahead_for_word,
|
|
lookbehind.ForMatch(backward),
|
|
stack_register, position_register);
|
|
RegExpNode* forward = TextNode::CreateForCharacterRanges(
|
|
word_range, false, lookahead.on_match_success(), flags);
|
|
result->AddAlternative(GuardedAlternative(lookahead.ForMatch(forward)));
|
|
}
|
|
return result;
|
|
}
|
|
} // anonymous namespace
|
|
|
|
RegExpNode* RegExpAssertion::ToNode(RegExpCompiler* compiler,
|
|
RegExpNode* on_success) {
|
|
switch (assertion_type()) {
|
|
case START_OF_LINE:
|
|
return AssertionNode::AfterNewline(on_success);
|
|
case START_OF_INPUT:
|
|
return AssertionNode::AtStart(on_success);
|
|
case BOUNDARY:
|
|
return flags_.NeedsUnicodeCaseEquivalents()
|
|
? BoundaryAssertionAsLookaround(compiler, on_success, BOUNDARY,
|
|
flags_)
|
|
: AssertionNode::AtBoundary(on_success);
|
|
case NON_BOUNDARY:
|
|
return flags_.NeedsUnicodeCaseEquivalents()
|
|
? BoundaryAssertionAsLookaround(compiler, on_success,
|
|
NON_BOUNDARY, flags_)
|
|
: AssertionNode::AtNonBoundary(on_success);
|
|
case END_OF_INPUT:
|
|
return AssertionNode::AtEnd(on_success);
|
|
case END_OF_LINE: {
|
|
// Compile $ in multiline regexps as an alternation with a positive
|
|
// lookahead in one side and an end-of-input on the other side.
|
|
// We need two registers for the lookahead.
|
|
intptr_t stack_pointer_register = compiler->AllocateRegister();
|
|
intptr_t position_register = compiler->AllocateRegister();
|
|
// The ChoiceNode to distinguish between a newline and end-of-input.
|
|
ChoiceNode* result = new ChoiceNode(2, on_success->zone());
|
|
// Create a newline atom.
|
|
ZoneGrowableArray<CharacterRange>* newline_ranges =
|
|
new ZoneGrowableArray<CharacterRange>(3);
|
|
CharacterRange::AddClassEscape('n', newline_ranges);
|
|
RegExpCharacterClass* newline_atom =
|
|
new RegExpCharacterClass('n', RegExpFlags());
|
|
TextNode* newline_matcher =
|
|
new TextNode(newline_atom, /*read_backwards=*/false,
|
|
ActionNode::PositiveSubmatchSuccess(
|
|
stack_pointer_register, position_register,
|
|
0, // No captures inside.
|
|
-1, // Ignored if no captures.
|
|
on_success));
|
|
// Create an end-of-input matcher.
|
|
RegExpNode* end_of_line = ActionNode::BeginSubmatch(
|
|
stack_pointer_register, position_register, newline_matcher);
|
|
// Add the two alternatives to the ChoiceNode.
|
|
GuardedAlternative eol_alternative(end_of_line);
|
|
result->AddAlternative(eol_alternative);
|
|
GuardedAlternative end_alternative(AssertionNode::AtEnd(on_success));
|
|
result->AddAlternative(end_alternative);
|
|
return result;
|
|
}
|
|
default:
|
|
UNREACHABLE();
|
|
}
|
|
return on_success;
|
|
}
|
|
|
|
RegExpNode* RegExpBackReference::ToNode(RegExpCompiler* compiler,
|
|
RegExpNode* on_success) {
|
|
return new (OZ) BackReferenceNode(RegExpCapture::StartRegister(index()),
|
|
RegExpCapture::EndRegister(index()), flags_,
|
|
compiler->read_backward(), on_success);
|
|
}
|
|
|
|
RegExpNode* RegExpEmpty::ToNode(RegExpCompiler* compiler,
|
|
RegExpNode* on_success) {
|
|
return on_success;
|
|
}
|
|
|
|
RegExpLookaround::Builder::Builder(bool is_positive,
|
|
RegExpNode* on_success,
|
|
intptr_t stack_pointer_register,
|
|
intptr_t position_register,
|
|
intptr_t capture_register_count,
|
|
intptr_t capture_register_start)
|
|
: is_positive_(is_positive),
|
|
on_success_(on_success),
|
|
stack_pointer_register_(stack_pointer_register),
|
|
position_register_(position_register) {
|
|
if (is_positive_) {
|
|
on_match_success_ = ActionNode::PositiveSubmatchSuccess(
|
|
stack_pointer_register, position_register, capture_register_count,
|
|
capture_register_start, on_success);
|
|
} else {
|
|
on_match_success_ = new (OZ) NegativeSubmatchSuccess(
|
|
stack_pointer_register, position_register, capture_register_count,
|
|
capture_register_start, OZ);
|
|
}
|
|
}
|
|
|
|
RegExpNode* RegExpLookaround::Builder::ForMatch(RegExpNode* match) {
|
|
if (is_positive_) {
|
|
return ActionNode::BeginSubmatch(stack_pointer_register_,
|
|
position_register_, match);
|
|
} else {
|
|
Zone* zone = on_success_->zone();
|
|
// We use a ChoiceNode to represent the negative lookaround. The first
|
|
// alternative is the negative match. On success, the end node backtracks.
|
|
// On failure, the second alternative is tried and leads to success.
|
|
// NegativeLookaroundChoiceNode is a special ChoiceNode that ignores the
|
|
// first exit when calculating quick checks.
|
|
ChoiceNode* choice_node = new (zone) NegativeLookaroundChoiceNode(
|
|
GuardedAlternative(match), GuardedAlternative(on_success_), zone);
|
|
return ActionNode::BeginSubmatch(stack_pointer_register_,
|
|
position_register_, choice_node);
|
|
}
|
|
}
|
|
|
|
RegExpNode* RegExpLookaround::ToNode(RegExpCompiler* compiler,
|
|
RegExpNode* on_success) {
|
|
intptr_t stack_pointer_register = compiler->AllocateRegister();
|
|
intptr_t position_register = compiler->AllocateRegister();
|
|
|
|
const intptr_t registers_per_capture = 2;
|
|
const intptr_t register_of_first_capture = 2;
|
|
intptr_t register_count = capture_count_ * registers_per_capture;
|
|
intptr_t register_start =
|
|
register_of_first_capture + capture_from_ * registers_per_capture;
|
|
|
|
RegExpNode* result;
|
|
bool was_reading_backward = compiler->read_backward();
|
|
compiler->set_read_backward(type() == LOOKBEHIND);
|
|
Builder builder(is_positive(), on_success, stack_pointer_register,
|
|
position_register, register_count, register_start);
|
|
RegExpNode* match = body_->ToNode(compiler, builder.on_match_success());
|
|
result = builder.ForMatch(match);
|
|
compiler->set_read_backward(was_reading_backward);
|
|
return result;
|
|
}
|
|
|
|
RegExpNode* RegExpCapture::ToNode(RegExpCompiler* compiler,
|
|
RegExpNode* on_success) {
|
|
return ToNode(body(), index(), compiler, on_success);
|
|
}
|
|
|
|
RegExpNode* RegExpCapture::ToNode(RegExpTree* body,
|
|
intptr_t index,
|
|
RegExpCompiler* compiler,
|
|
RegExpNode* on_success) {
|
|
ASSERT(body != nullptr);
|
|
intptr_t start_reg = RegExpCapture::StartRegister(index);
|
|
intptr_t end_reg = RegExpCapture::EndRegister(index);
|
|
if (compiler->read_backward()) {
|
|
intptr_t tmp = end_reg;
|
|
end_reg = start_reg;
|
|
start_reg = tmp;
|
|
}
|
|
RegExpNode* store_end = ActionNode::StorePosition(end_reg, true, on_success);
|
|
RegExpNode* body_node = body->ToNode(compiler, store_end);
|
|
return ActionNode::StorePosition(start_reg, true, body_node);
|
|
}
|
|
|
|
RegExpNode* RegExpAlternative::ToNode(RegExpCompiler* compiler,
|
|
RegExpNode* on_success) {
|
|
ZoneGrowableArray<RegExpTree*>* children = nodes();
|
|
RegExpNode* current = on_success;
|
|
if (compiler->read_backward()) {
|
|
for (intptr_t i = 0; i < children->length(); i++) {
|
|
current = children->At(i)->ToNode(compiler, current);
|
|
}
|
|
} else {
|
|
for (intptr_t i = children->length() - 1; i >= 0; i--) {
|
|
current = children->At(i)->ToNode(compiler, current);
|
|
}
|
|
}
|
|
return current;
|
|
}
|
|
|
|
static void AddClass(const int32_t* elmv,
|
|
intptr_t elmc,
|
|
ZoneGrowableArray<CharacterRange>* ranges) {
|
|
elmc--;
|
|
ASSERT(elmv[elmc] == kRangeEndMarker);
|
|
for (intptr_t i = 0; i < elmc; i += 2) {
|
|
ASSERT(elmv[i] < elmv[i + 1]);
|
|
ranges->Add(CharacterRange(elmv[i], elmv[i + 1] - 1));
|
|
}
|
|
}
|
|
|
|
static void AddClassNegated(const int32_t* elmv,
|
|
intptr_t elmc,
|
|
ZoneGrowableArray<CharacterRange>* ranges) {
|
|
elmc--;
|
|
ASSERT(elmv[elmc] == kRangeEndMarker);
|
|
ASSERT(elmv[0] != 0x0000);
|
|
ASSERT(elmv[elmc - 1] != Utf::kMaxCodePoint);
|
|
uint16_t last = 0x0000;
|
|
for (intptr_t i = 0; i < elmc; i += 2) {
|
|
ASSERT(last <= elmv[i] - 1);
|
|
ASSERT(elmv[i] < elmv[i + 1]);
|
|
ranges->Add(CharacterRange(last, elmv[i] - 1));
|
|
last = elmv[i + 1];
|
|
}
|
|
ranges->Add(CharacterRange(last, Utf::kMaxCodePoint));
|
|
}
|
|
|
|
void CharacterRange::AddClassEscape(uint16_t type,
|
|
ZoneGrowableArray<CharacterRange>* ranges,
|
|
bool add_unicode_case_equivalents) {
|
|
if (add_unicode_case_equivalents && (type == 'w' || type == 'W')) {
|
|
// See #sec-runtime-semantics-wordcharacters-abstract-operation
|
|
// In case of unicode and ignore_case, we need to create the closure over
|
|
// case equivalent characters before negating.
|
|
ZoneGrowableArray<CharacterRange>* new_ranges =
|
|
new ZoneGrowableArray<CharacterRange>(2);
|
|
AddClass(kWordRanges, kWordRangeCount, new_ranges);
|
|
AddUnicodeCaseEquivalents(new_ranges);
|
|
if (type == 'W') {
|
|
ZoneGrowableArray<CharacterRange>* negated =
|
|
new ZoneGrowableArray<CharacterRange>(2);
|
|
CharacterRange::Negate(new_ranges, negated);
|
|
new_ranges = negated;
|
|
}
|
|
ranges->AddArray(*new_ranges);
|
|
return;
|
|
}
|
|
AddClassEscape(type, ranges);
|
|
}
|
|
|
|
void CharacterRange::AddClassEscape(uint16_t type,
|
|
ZoneGrowableArray<CharacterRange>* ranges) {
|
|
switch (type) {
|
|
case 's':
|
|
AddClass(kSpaceRanges, kSpaceRangeCount, ranges);
|
|
break;
|
|
case 'S':
|
|
AddClassNegated(kSpaceRanges, kSpaceRangeCount, ranges);
|
|
break;
|
|
case 'w':
|
|
AddClass(kWordRanges, kWordRangeCount, ranges);
|
|
break;
|
|
case 'W':
|
|
AddClassNegated(kWordRanges, kWordRangeCount, ranges);
|
|
break;
|
|
case 'd':
|
|
AddClass(kDigitRanges, kDigitRangeCount, ranges);
|
|
break;
|
|
case 'D':
|
|
AddClassNegated(kDigitRanges, kDigitRangeCount, ranges);
|
|
break;
|
|
case '.':
|
|
AddClassNegated(kLineTerminatorRanges, kLineTerminatorRangeCount, ranges);
|
|
break;
|
|
// This is not a character range as defined by the spec but a
|
|
// convenient shorthand for a character class that matches any
|
|
// character.
|
|
case '*':
|
|
ranges->Add(CharacterRange::Everything());
|
|
break;
|
|
// This is the set of characters matched by the $ and ^ symbols
|
|
// in multiline mode.
|
|
case 'n':
|
|
AddClass(kLineTerminatorRanges, kLineTerminatorRangeCount, ranges);
|
|
break;
|
|
default:
|
|
UNREACHABLE();
|
|
}
|
|
}
|
|
|
|
void CharacterRange::AddCaseEquivalents(
|
|
ZoneGrowableArray<CharacterRange>* ranges,
|
|
bool is_one_byte,
|
|
Zone* zone) {
|
|
CharacterRange::Canonicalize(ranges);
|
|
int range_count = ranges->length();
|
|
for (intptr_t i = 0; i < range_count; i++) {
|
|
CharacterRange range = ranges->At(i);
|
|
int32_t bottom = range.from();
|
|
if (bottom > Utf16::kMaxCodeUnit) continue;
|
|
int32_t top = Utils::Minimum(range.to(), Utf16::kMaxCodeUnit);
|
|
// Nothing to be done for surrogates
|
|
if (bottom >= Utf16::kLeadSurrogateStart &&
|
|
top <= Utf16::kTrailSurrogateEnd) {
|
|
continue;
|
|
}
|
|
if (is_one_byte && !RangeContainsLatin1Equivalents(range)) {
|
|
if (bottom > Symbols::kMaxOneCharCodeSymbol) continue;
|
|
if (top > Symbols::kMaxOneCharCodeSymbol) {
|
|
top = Symbols::kMaxOneCharCodeSymbol;
|
|
}
|
|
}
|
|
|
|
unibrow::Mapping<unibrow::Ecma262UnCanonicalize> jsregexp_uncanonicalize;
|
|
unibrow::Mapping<unibrow::CanonicalizationRange> jsregexp_canonrange;
|
|
int32_t chars[unibrow::Ecma262UnCanonicalize::kMaxWidth];
|
|
if (top == bottom) {
|
|
// If this is a singleton we just expand the one character.
|
|
intptr_t length = jsregexp_uncanonicalize.get(bottom, '\0', chars);
|
|
for (intptr_t i = 0; i < length; i++) {
|
|
int32_t chr = chars[i];
|
|
if (chr != bottom) {
|
|
ranges->Add(CharacterRange::Singleton(chars[i]));
|
|
}
|
|
}
|
|
} else {
|
|
// If this is a range we expand the characters block by block,
|
|
// expanding contiguous subranges (blocks) one at a time.
|
|
// The approach is as follows. For a given start character we
|
|
// look up the remainder of the block that contains it (represented
|
|
// by the end point), for instance we find 'z' if the character
|
|
// is 'c'. A block is characterized by the property
|
|
// that all characters uncanonicalize in the same way, except that
|
|
// each entry in the result is incremented by the distance from the first
|
|
// element. So a-z is a block because 'a' uncanonicalizes to ['a', 'A']
|
|
// and the k'th letter uncanonicalizes to ['a' + k, 'A' + k].
|
|
// Once we've found the end point we look up its uncanonicalization
|
|
// and produce a range for each element. For instance for [c-f]
|
|
// we look up ['z', 'Z'] and produce [c-f] and [C-F]. We then only
|
|
// add a range if it is not already contained in the input, so [c-f]
|
|
// will be skipped but [C-F] will be added. If this range is not
|
|
// completely contained in a block we do this for all the blocks
|
|
// covered by the range (handling characters that is not in a block
|
|
// as a "singleton block").
|
|
int32_t range[unibrow::Ecma262UnCanonicalize::kMaxWidth];
|
|
intptr_t pos = bottom;
|
|
while (pos <= top) {
|
|
intptr_t length = jsregexp_canonrange.get(pos, '\0', range);
|
|
int32_t block_end;
|
|
if (length == 0) {
|
|
block_end = pos;
|
|
} else {
|
|
ASSERT(length == 1);
|
|
block_end = range[0];
|
|
}
|
|
intptr_t end = (block_end > top) ? top : block_end;
|
|
length = jsregexp_uncanonicalize.get(block_end, '\0', range);
|
|
for (intptr_t i = 0; i < length; i++) {
|
|
int32_t c = range[i];
|
|
int32_t range_from = c - (block_end - pos);
|
|
int32_t range_to = c - (block_end - end);
|
|
if (!(bottom <= range_from && range_to <= top)) {
|
|
ranges->Add(CharacterRange(range_from, range_to));
|
|
}
|
|
}
|
|
pos = end + 1;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
bool CharacterRange::IsCanonical(ZoneGrowableArray<CharacterRange>* ranges) {
|
|
ASSERT(ranges != NULL);
|
|
intptr_t n = ranges->length();
|
|
if (n <= 1) return true;
|
|
intptr_t max = ranges->At(0).to();
|
|
for (intptr_t i = 1; i < n; i++) {
|
|
CharacterRange next_range = ranges->At(i);
|
|
if (next_range.from() <= max + 1) return false;
|
|
max = next_range.to();
|
|
}
|
|
return true;
|
|
}
|
|
|
|
ZoneGrowableArray<CharacterRange>* CharacterSet::ranges() {
|
|
if (ranges_ == NULL) {
|
|
ranges_ = new ZoneGrowableArray<CharacterRange>(2);
|
|
CharacterRange::AddClassEscape(standard_set_type_, ranges_);
|
|
}
|
|
return ranges_;
|
|
}
|
|
|
|
// Move a number of elements in a zone array to another position
|
|
// in the same array. Handles overlapping source and target areas.
|
|
static void MoveRanges(ZoneGrowableArray<CharacterRange>* list,
|
|
intptr_t from,
|
|
intptr_t to,
|
|
intptr_t count) {
|
|
// Ranges are potentially overlapping.
|
|
if (from < to) {
|
|
for (intptr_t i = count - 1; i >= 0; i--) {
|
|
(*list)[to + i] = list->At(from + i);
|
|
}
|
|
} else {
|
|
for (intptr_t i = 0; i < count; i++) {
|
|
(*list)[to + i] = list->At(from + i);
|
|
}
|
|
}
|
|
}
|
|
|
|
static intptr_t InsertRangeInCanonicalList(
|
|
ZoneGrowableArray<CharacterRange>* list,
|
|
intptr_t count,
|
|
CharacterRange insert) {
|
|
// Inserts a range into list[0..count[, which must be sorted
|
|
// by from value and non-overlapping and non-adjacent, using at most
|
|
// list[0..count] for the result. Returns the number of resulting
|
|
// canonicalized ranges. Inserting a range may collapse existing ranges into
|
|
// fewer ranges, so the return value can be anything in the range 1..count+1.
|
|
int32_t from = insert.from();
|
|
int32_t to = insert.to();
|
|
intptr_t start_pos = 0;
|
|
intptr_t end_pos = count;
|
|
for (intptr_t i = count - 1; i >= 0; i--) {
|
|
CharacterRange current = list->At(i);
|
|
if (current.from() > to + 1) {
|
|
end_pos = i;
|
|
} else if (current.to() + 1 < from) {
|
|
start_pos = i + 1;
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Inserted range overlaps, or is adjacent to, ranges at positions
|
|
// [start_pos..end_pos[. Ranges before start_pos or at or after end_pos are
|
|
// not affected by the insertion.
|
|
// If start_pos == end_pos, the range must be inserted before start_pos.
|
|
// if start_pos < end_pos, the entire range from start_pos to end_pos
|
|
// must be merged with the insert range.
|
|
|
|
if (start_pos == end_pos) {
|
|
// Insert between existing ranges at position start_pos.
|
|
if (start_pos < count) {
|
|
MoveRanges(list, start_pos, start_pos + 1, count - start_pos);
|
|
}
|
|
(*list)[start_pos] = insert;
|
|
return count + 1;
|
|
}
|
|
if (start_pos + 1 == end_pos) {
|
|
// Replace single existing range at position start_pos.
|
|
CharacterRange to_replace = list->At(start_pos);
|
|
intptr_t new_from = Utils::Minimum(to_replace.from(), from);
|
|
intptr_t new_to = Utils::Maximum(to_replace.to(), to);
|
|
(*list)[start_pos] = CharacterRange(new_from, new_to);
|
|
return count;
|
|
}
|
|
// Replace a number of existing ranges from start_pos to end_pos - 1.
|
|
// Move the remaining ranges down.
|
|
|
|
intptr_t new_from = Utils::Minimum(list->At(start_pos).from(), from);
|
|
intptr_t new_to = Utils::Maximum(list->At(end_pos - 1).to(), to);
|
|
if (end_pos < count) {
|
|
MoveRanges(list, end_pos, start_pos + 1, count - end_pos);
|
|
}
|
|
(*list)[start_pos] = CharacterRange(new_from, new_to);
|
|
return count - (end_pos - start_pos) + 1;
|
|
}
|
|
|
|
void CharacterSet::Canonicalize() {
|
|
// Special/default classes are always considered canonical. The result
|
|
// of calling ranges() will be sorted.
|
|
if (ranges_ == NULL) return;
|
|
CharacterRange::Canonicalize(ranges_);
|
|
}
|
|
|
|
void CharacterRange::Canonicalize(
|
|
ZoneGrowableArray<CharacterRange>* character_ranges) {
|
|
if (character_ranges->length() <= 1) return;
|
|
// Check whether ranges are already canonical (increasing, non-overlapping,
|
|
// non-adjacent).
|
|
intptr_t n = character_ranges->length();
|
|
intptr_t max = character_ranges->At(0).to();
|
|
intptr_t i = 1;
|
|
while (i < n) {
|
|
CharacterRange current = character_ranges->At(i);
|
|
if (current.from() <= max + 1) {
|
|
break;
|
|
}
|
|
max = current.to();
|
|
i++;
|
|
}
|
|
// Canonical until the i'th range. If that's all of them, we are done.
|
|
if (i == n) return;
|
|
|
|
// The ranges at index i and forward are not canonicalized. Make them so by
|
|
// doing the equivalent of insertion sort (inserting each into the previous
|
|
// list, in order).
|
|
// Notice that inserting a range can reduce the number of ranges in the
|
|
// result due to combining of adjacent and overlapping ranges.
|
|
intptr_t read = i; // Range to insert.
|
|
intptr_t num_canonical = i; // Length of canonicalized part of list.
|
|
do {
|
|
num_canonical = InsertRangeInCanonicalList(character_ranges, num_canonical,
|
|
character_ranges->At(read));
|
|
read++;
|
|
} while (read < n);
|
|
character_ranges->TruncateTo(num_canonical);
|
|
|
|
ASSERT(CharacterRange::IsCanonical(character_ranges));
|
|
}
|
|
|
|
void CharacterRange::Negate(ZoneGrowableArray<CharacterRange>* ranges,
|
|
ZoneGrowableArray<CharacterRange>* negated_ranges) {
|
|
ASSERT(CharacterRange::IsCanonical(ranges));
|
|
ASSERT(negated_ranges->length() == 0);
|
|
intptr_t range_count = ranges->length();
|
|
uint32_t from = 0;
|
|
intptr_t i = 0;
|
|
if (range_count > 0 && ranges->At(0).from() == 0) {
|
|
from = ranges->At(0).to();
|
|
i = 1;
|
|
}
|
|
while (i < range_count) {
|
|
CharacterRange range = ranges->At(i);
|
|
negated_ranges->Add(CharacterRange(from + 1, range.from() - 1));
|
|
from = range.to();
|
|
i++;
|
|
}
|
|
if (from < Utf::kMaxCodePoint) {
|
|
negated_ranges->Add(CharacterRange(from + 1, Utf::kMaxCodePoint));
|
|
}
|
|
}
|
|
|
|
// -------------------------------------------------------------------
|
|
// Splay tree
|
|
|
|
// Workaround for the fact that ZoneGrowableArray does not have contains().
|
|
static bool ArrayContains(ZoneGrowableArray<unsigned>* array, unsigned value) {
|
|
for (intptr_t i = 0; i < array->length(); i++) {
|
|
if (array->At(i) == value) {
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
OutSet* OutSet::Extend(unsigned value, Zone* zone) {
|
|
if (Get(value)) return this;
|
|
if (successors() != nullptr) {
|
|
for (int i = 0; i < successors()->length(); i++) {
|
|
OutSet* successor = successors()->At(i);
|
|
if (successor->Get(value)) return successor;
|
|
}
|
|
} else {
|
|
successors_ = new (zone) ZoneGrowableArray<OutSet*>(2);
|
|
}
|
|
OutSet* result = new (zone) OutSet(first_, remaining_);
|
|
result->Set(value, zone);
|
|
successors()->Add(result);
|
|
return result;
|
|
}
|
|
|
|
void OutSet::Set(unsigned value, Zone* zone) {
|
|
if (value < kFirstLimit) {
|
|
first_ |= (1 << value);
|
|
} else {
|
|
if (remaining_ == NULL)
|
|
remaining_ = new (zone) ZoneGrowableArray<unsigned>(1);
|
|
|
|
bool remaining_contains_value = ArrayContains(remaining_, value);
|
|
if (remaining_->is_empty() || !remaining_contains_value) {
|
|
remaining_->Add(value);
|
|
}
|
|
}
|
|
}
|
|
|
|
bool OutSet::Get(unsigned value) const {
|
|
if (value < kFirstLimit) {
|
|
return (first_ & (1 << value)) != 0;
|
|
} else if (remaining_ == NULL) {
|
|
return false;
|
|
} else {
|
|
return ArrayContains(remaining_, value);
|
|
}
|
|
}
|
|
|
|
const int32_t DispatchTable::Config::kNoKey = Utf::kInvalidChar;
|
|
|
|
void DispatchTable::AddRange(CharacterRange full_range,
|
|
int32_t value,
|
|
Zone* zone) {
|
|
CharacterRange current = full_range;
|
|
if (tree()->is_empty()) {
|
|
// If this is the first range we just insert into the table.
|
|
ZoneSplayTree<Config>::Locator loc;
|
|
bool inserted = tree()->Insert(current.from(), &loc);
|
|
ASSERT(inserted);
|
|
USE(inserted);
|
|
loc.set_value(
|
|
Entry(current.from(), current.to(), empty()->Extend(value, zone)));
|
|
return;
|
|
}
|
|
// First see if there is a range to the left of this one that
|
|
// overlaps.
|
|
ZoneSplayTree<Config>::Locator loc;
|
|
if (tree()->FindGreatestLessThan(current.from(), &loc)) {
|
|
Entry* entry = &loc.value();
|
|
// If we've found a range that overlaps with this one, and it
|
|
// starts strictly to the left of this one, we have to fix it
|
|
// because the following code only handles ranges that start on
|
|
// or after the start point of the range we're adding.
|
|
if (entry->from() < current.from() && entry->to() >= current.from()) {
|
|
// Snap the overlapping range in half around the start point of
|
|
// the range we're adding.
|
|
CharacterRange left =
|
|
CharacterRange::Range(entry->from(), current.from() - 1);
|
|
CharacterRange right = CharacterRange::Range(current.from(), entry->to());
|
|
// The left part of the overlapping range doesn't overlap.
|
|
// Truncate the whole entry to be just the left part.
|
|
entry->set_to(left.to());
|
|
// The right part is the one that overlaps. We add this part
|
|
// to the map and let the next step deal with merging it with
|
|
// the range we're adding.
|
|
ZoneSplayTree<Config>::Locator loc;
|
|
bool inserted = tree()->Insert(right.from(), &loc);
|
|
ASSERT(inserted);
|
|
USE(inserted);
|
|
loc.set_value(Entry(right.from(), right.to(), entry->out_set()));
|
|
}
|
|
}
|
|
while (current.is_valid()) {
|
|
if (tree()->FindLeastGreaterThan(current.from(), &loc) &&
|
|
(loc.value().from() <= current.to()) &&
|
|
(loc.value().to() >= current.from())) {
|
|
Entry* entry = &loc.value();
|
|
// We have overlap. If there is space between the start point of
|
|
// the range we're adding and where the overlapping range starts
|
|
// then we have to add a range covering just that space.
|
|
if (current.from() < entry->from()) {
|
|
ZoneSplayTree<Config>::Locator ins;
|
|
bool inserted = tree()->Insert(current.from(), &ins);
|
|
ASSERT(inserted);
|
|
USE(inserted);
|
|
ins.set_value(Entry(current.from(), entry->from() - 1,
|
|
empty()->Extend(value, zone)));
|
|
current.set_from(entry->from());
|
|
}
|
|
ASSERT(current.from() == entry->from());
|
|
// If the overlapping range extends beyond the one we want to add
|
|
// we have to snap the right part off and add it separately.
|
|
if (entry->to() > current.to()) {
|
|
ZoneSplayTree<Config>::Locator ins;
|
|
bool inserted = tree()->Insert(current.to() + 1, &ins);
|
|
ASSERT(inserted);
|
|
USE(inserted);
|
|
ins.set_value(Entry(current.to() + 1, entry->to(), entry->out_set()));
|
|
entry->set_to(current.to());
|
|
}
|
|
ASSERT(entry->to() <= current.to());
|
|
// The overlapping range is now completely contained by the range
|
|
// we're adding so we can just update it and move the start point
|
|
// of the range we're adding just past it.
|
|
entry->AddValue(value, zone);
|
|
ASSERT(entry->to() + 1 > current.from());
|
|
current.set_from(entry->to() + 1);
|
|
} else {
|
|
// There is no overlap so we can just add the range
|
|
ZoneSplayTree<Config>::Locator ins;
|
|
bool inserted = tree()->Insert(current.from(), &ins);
|
|
ASSERT(inserted);
|
|
USE(inserted);
|
|
ins.set_value(
|
|
Entry(current.from(), current.to(), empty()->Extend(value, zone)));
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
OutSet* DispatchTable::Get(int32_t value) {
|
|
ZoneSplayTree<Config>::Locator loc;
|
|
if (!tree()->FindGreatestLessThan(value, &loc)) return empty();
|
|
Entry* entry = &loc.value();
|
|
if (value <= entry->to())
|
|
return entry->out_set();
|
|
else
|
|
return empty();
|
|
}
|
|
|
|
// -------------------------------------------------------------------
|
|
// Analysis
|
|
|
|
void Analysis::EnsureAnalyzed(RegExpNode* that) {
|
|
if (that->info()->been_analyzed || that->info()->being_analyzed) return;
|
|
that->info()->being_analyzed = true;
|
|
that->Accept(this);
|
|
that->info()->being_analyzed = false;
|
|
that->info()->been_analyzed = true;
|
|
}
|
|
|
|
void Analysis::VisitEnd(EndNode* that) {
|
|
// nothing to do
|
|
}
|
|
|
|
void TextNode::CalculateOffsets() {
|
|
intptr_t element_count = elements()->length();
|
|
// Set up the offsets of the elements relative to the start. This is a fixed
|
|
// quantity since a TextNode can only contain fixed-width things.
|
|
intptr_t cp_offset = 0;
|
|
for (intptr_t i = 0; i < element_count; i++) {
|
|
TextElement& elm = (*elements())[i];
|
|
elm.set_cp_offset(cp_offset);
|
|
cp_offset += elm.length();
|
|
}
|
|
}
|
|
|
|
void Analysis::VisitText(TextNode* that) {
|
|
that->MakeCaseIndependent(is_one_byte_);
|
|
EnsureAnalyzed(that->on_success());
|
|
if (!has_failed()) {
|
|
that->CalculateOffsets();
|
|
}
|
|
}
|
|
|
|
void Analysis::VisitAction(ActionNode* that) {
|
|
RegExpNode* target = that->on_success();
|
|
EnsureAnalyzed(target);
|
|
if (!has_failed()) {
|
|
// If the next node is interested in what it follows then this node
|
|
// has to be interested too so it can pass the information on.
|
|
that->info()->AddFromFollowing(target->info());
|
|
}
|
|
}
|
|
|
|
void Analysis::VisitChoice(ChoiceNode* that) {
|
|
NodeInfo* info = that->info();
|
|
for (intptr_t i = 0; i < that->alternatives()->length(); i++) {
|
|
RegExpNode* node = (*that->alternatives())[i].node();
|
|
EnsureAnalyzed(node);
|
|
if (has_failed()) return;
|
|
// Anything the following nodes need to know has to be known by
|
|
// this node also, so it can pass it on.
|
|
info->AddFromFollowing(node->info());
|
|
}
|
|
}
|
|
|
|
void Analysis::VisitLoopChoice(LoopChoiceNode* that) {
|
|
NodeInfo* info = that->info();
|
|
for (intptr_t i = 0; i < that->alternatives()->length(); i++) {
|
|
RegExpNode* node = (*that->alternatives())[i].node();
|
|
if (node != that->loop_node()) {
|
|
EnsureAnalyzed(node);
|
|
if (has_failed()) return;
|
|
info->AddFromFollowing(node->info());
|
|
}
|
|
}
|
|
// Check the loop last since it may need the value of this node
|
|
// to get a correct result.
|
|
EnsureAnalyzed(that->loop_node());
|
|
if (!has_failed()) {
|
|
info->AddFromFollowing(that->loop_node()->info());
|
|
}
|
|
}
|
|
|
|
void Analysis::VisitBackReference(BackReferenceNode* that) {
|
|
EnsureAnalyzed(that->on_success());
|
|
}
|
|
|
|
void Analysis::VisitAssertion(AssertionNode* that) {
|
|
EnsureAnalyzed(that->on_success());
|
|
}
|
|
|
|
void BackReferenceNode::FillInBMInfo(intptr_t offset,
|
|
intptr_t budget,
|
|
BoyerMooreLookahead* bm,
|
|
bool not_at_start) {
|
|
// Working out the set of characters that a backreference can match is too
|
|
// hard, so we just say that any character can match.
|
|
bm->SetRest(offset);
|
|
SaveBMInfo(bm, not_at_start, offset);
|
|
}
|
|
|
|
COMPILE_ASSERT(BoyerMoorePositionInfo::kMapSize ==
|
|
RegExpMacroAssembler::kTableSize);
|
|
|
|
void ChoiceNode::FillInBMInfo(intptr_t offset,
|
|
intptr_t budget,
|
|
BoyerMooreLookahead* bm,
|
|
bool not_at_start) {
|
|
ZoneGrowableArray<GuardedAlternative>* alts = alternatives();
|
|
budget = (budget - 1) / alts->length();
|
|
for (intptr_t i = 0; i < alts->length(); i++) {
|
|
GuardedAlternative& alt = (*alts)[i];
|
|
if (alt.guards() != NULL && alt.guards()->length() != 0) {
|
|
bm->SetRest(offset); // Give up trying to fill in info.
|
|
SaveBMInfo(bm, not_at_start, offset);
|
|
return;
|
|
}
|
|
alt.node()->FillInBMInfo(offset, budget, bm, not_at_start);
|
|
}
|
|
SaveBMInfo(bm, not_at_start, offset);
|
|
}
|
|
|
|
void TextNode::FillInBMInfo(intptr_t initial_offset,
|
|
intptr_t budget,
|
|
BoyerMooreLookahead* bm,
|
|
bool not_at_start) {
|
|
if (initial_offset >= bm->length()) return;
|
|
intptr_t offset = initial_offset;
|
|
intptr_t max_char = bm->max_char();
|
|
for (intptr_t i = 0; i < elements()->length(); i++) {
|
|
if (offset >= bm->length()) {
|
|
if (initial_offset == 0) set_bm_info(not_at_start, bm);
|
|
return;
|
|
}
|
|
TextElement text = elements()->At(i);
|
|
if (text.text_type() == TextElement::ATOM) {
|
|
RegExpAtom* atom = text.atom();
|
|
for (intptr_t j = 0; j < atom->length(); j++, offset++) {
|
|
if (offset >= bm->length()) {
|
|
if (initial_offset == 0) set_bm_info(not_at_start, bm);
|
|
return;
|
|
}
|
|
uint16_t character = atom->data()->At(j);
|
|
if (atom->flags().IgnoreCase()) {
|
|
int32_t chars[unibrow::Ecma262UnCanonicalize::kMaxWidth];
|
|
intptr_t length = GetCaseIndependentLetters(
|
|
character, bm->max_char() == Symbols::kMaxOneCharCodeSymbol,
|
|
chars);
|
|
for (intptr_t j = 0; j < length; j++) {
|
|
bm->Set(offset, chars[j]);
|
|
}
|
|
} else {
|
|
if (character <= max_char) bm->Set(offset, character);
|
|
}
|
|
}
|
|
} else {
|
|
ASSERT(text.text_type() == TextElement::CHAR_CLASS);
|
|
RegExpCharacterClass* char_class = text.char_class();
|
|
ZoneGrowableArray<CharacterRange>* ranges = char_class->ranges();
|
|
if (char_class->is_negated()) {
|
|
bm->SetAll(offset);
|
|
} else {
|
|
for (intptr_t k = 0; k < ranges->length(); k++) {
|
|
const CharacterRange& range = ranges->At(k);
|
|
if (range.from() > max_char) continue;
|
|
intptr_t to =
|
|
Utils::Minimum(max_char, static_cast<intptr_t>(range.to()));
|
|
bm->SetInterval(offset, Interval(range.from(), to));
|
|
}
|
|
}
|
|
offset++;
|
|
}
|
|
}
|
|
if (offset >= bm->length()) {
|
|
if (initial_offset == 0) set_bm_info(not_at_start, bm);
|
|
return;
|
|
}
|
|
on_success()->FillInBMInfo(offset, budget - 1, bm,
|
|
true); // Not at start after a text node.
|
|
if (initial_offset == 0) set_bm_info(not_at_start, bm);
|
|
}
|
|
|
|
RegExpNode* OptionallyStepBackToLeadSurrogate(RegExpCompiler* compiler,
|
|
RegExpNode* on_success,
|
|
RegExpFlags flags) {
|
|
// If the regexp matching starts within a surrogate pair, step back
|
|
// to the lead surrogate and start matching from there.
|
|
ASSERT(!compiler->read_backward());
|
|
Zone* zone = compiler->zone();
|
|
|
|
auto lead_surrogates = CharacterRange::List(
|
|
on_success->zone(), CharacterRange::Range(Utf16::kLeadSurrogateStart,
|
|
Utf16::kLeadSurrogateEnd));
|
|
auto trail_surrogates = CharacterRange::List(
|
|
on_success->zone(), CharacterRange::Range(Utf16::kTrailSurrogateStart,
|
|
Utf16::kTrailSurrogateEnd));
|
|
|
|
ChoiceNode* optional_step_back = new (zone) ChoiceNode(2, zone);
|
|
|
|
int stack_register = compiler->UnicodeLookaroundStackRegister();
|
|
int position_register = compiler->UnicodeLookaroundPositionRegister();
|
|
RegExpNode* step_back = TextNode::CreateForCharacterRanges(
|
|
lead_surrogates, /*read_backward=*/true, on_success, flags);
|
|
RegExpLookaround::Builder builder(/*is_positive=*/true, step_back,
|
|
stack_register, position_register);
|
|
RegExpNode* match_trail = TextNode::CreateForCharacterRanges(
|
|
trail_surrogates, /*read_backward=*/false, builder.on_match_success(),
|
|
flags);
|
|
|
|
optional_step_back->AddAlternative(
|
|
GuardedAlternative(builder.ForMatch(match_trail)));
|
|
optional_step_back->AddAlternative(GuardedAlternative(on_success));
|
|
|
|
return optional_step_back;
|
|
}
|
|
|
|
#if !defined(DART_PRECOMPILED_RUNTIME)
|
|
RegExpEngine::CompilationResult RegExpEngine::CompileIR(
|
|
RegExpCompileData* data,
|
|
const ParsedFunction* parsed_function,
|
|
const ZoneGrowableArray<const ICData*>& ic_data_array,
|
|
intptr_t osr_id) {
|
|
ASSERT(!FLAG_interpret_irregexp);
|
|
Zone* zone = Thread::Current()->zone();
|
|
|
|
const Function& function = parsed_function->function();
|
|
const intptr_t specialization_cid = function.string_specialization_cid();
|
|
const bool is_sticky = function.is_sticky_specialization();
|
|
const bool is_one_byte = (specialization_cid == kOneByteStringCid ||
|
|
specialization_cid == kExternalOneByteStringCid);
|
|
RegExp& regexp = RegExp::Handle(zone, function.regexp());
|
|
const String& pattern = String::Handle(zone, regexp.pattern());
|
|
|
|
ASSERT(!regexp.IsNull());
|
|
ASSERT(!pattern.IsNull());
|
|
|
|
const bool is_global = regexp.flags().IsGlobal();
|
|
const bool is_unicode = regexp.flags().IsUnicode();
|
|
|
|
RegExpCompiler compiler(data->capture_count, is_one_byte);
|
|
|
|
// TODO(zerny): Frequency sampling is currently disabled because of several
|
|
// issues. We do not want to store subject strings in the regexp object since
|
|
// they might be long and we should not prevent their garbage collection.
|
|
// Passing them to this function explicitly does not help, since we must
|
|
// generate exactly the same IR for both the unoptimizing and optimizing
|
|
// pipelines (otherwise it gets confused when i.e. deopt id's differ).
|
|
// An option would be to store sampling results in the regexp object, but
|
|
// I'm not sure the performance gains are relevant enough.
|
|
|
|
// Wrap the body of the regexp in capture #0.
|
|
RegExpNode* captured_body =
|
|
RegExpCapture::ToNode(data->tree, 0, &compiler, compiler.accept());
|
|
|
|
RegExpNode* node = captured_body;
|
|
const bool is_end_anchored = data->tree->IsAnchoredAtEnd();
|
|
const bool is_start_anchored = data->tree->IsAnchoredAtStart();
|
|
intptr_t max_length = data->tree->max_match();
|
|
if (!is_start_anchored && !is_sticky) {
|
|
// Add a .*? at the beginning, outside the body capture, unless
|
|
// this expression is anchored at the beginning or is sticky.
|
|
RegExpNode* loop_node = RegExpQuantifier::ToNode(
|
|
0, RegExpTree::kInfinity, false,
|
|
new (zone) RegExpCharacterClass('*', RegExpFlags()), &compiler,
|
|
captured_body, data->contains_anchor);
|
|
|
|
if (data->contains_anchor) {
|
|
// Unroll loop once, to take care of the case that might start
|
|
// at the start of input.
|
|
ChoiceNode* first_step_node = new (zone) ChoiceNode(2, zone);
|
|
first_step_node->AddAlternative(GuardedAlternative(captured_body));
|
|
first_step_node->AddAlternative(GuardedAlternative(new (zone) TextNode(
|
|
new (zone) RegExpCharacterClass('*', RegExpFlags()),
|
|
/*read_backwards=*/false, loop_node)));
|
|
node = first_step_node;
|
|
} else {
|
|
node = loop_node;
|
|
}
|
|
}
|
|
if (is_one_byte) {
|
|
node = node->FilterOneByte(RegExpCompiler::kMaxRecursion);
|
|
// Do it again to propagate the new nodes to places where they were not
|
|
// put because they had not been calculated yet.
|
|
if (node != NULL) {
|
|
node = node->FilterOneByte(RegExpCompiler::kMaxRecursion);
|
|
}
|
|
} else if (is_unicode && (is_global || is_sticky)) {
|
|
node = OptionallyStepBackToLeadSurrogate(&compiler, node, regexp.flags());
|
|
}
|
|
|
|
if (node == NULL) node = new (zone) EndNode(EndNode::BACKTRACK, zone);
|
|
data->node = node;
|
|
Analysis analysis(is_one_byte);
|
|
analysis.EnsureAnalyzed(node);
|
|
if (analysis.has_failed()) {
|
|
const char* error_message = analysis.error_message();
|
|
return CompilationResult(error_message);
|
|
}
|
|
|
|
// Native regexp implementation.
|
|
|
|
IRRegExpMacroAssembler* macro_assembler = new (zone)
|
|
IRRegExpMacroAssembler(specialization_cid, data->capture_count,
|
|
parsed_function, ic_data_array, osr_id, zone);
|
|
|
|
// Inserted here, instead of in Assembler, because it depends on information
|
|
// in the AST that isn't replicated in the Node structure.
|
|
static const intptr_t kMaxBacksearchLimit = 1024;
|
|
if (is_end_anchored && !is_start_anchored && !is_sticky &&
|
|
max_length < kMaxBacksearchLimit) {
|
|
macro_assembler->SetCurrentPositionFromEnd(max_length);
|
|
}
|
|
|
|
if (is_global) {
|
|
RegExpMacroAssembler::GlobalMode mode = RegExpMacroAssembler::GLOBAL;
|
|
if (data->tree->min_match() > 0) {
|
|
mode = RegExpMacroAssembler::GLOBAL_NO_ZERO_LENGTH_CHECK;
|
|
} else if (is_unicode) {
|
|
mode = RegExpMacroAssembler::GLOBAL_UNICODE;
|
|
}
|
|
macro_assembler->set_global_mode(mode);
|
|
}
|
|
|
|
RegExpEngine::CompilationResult result =
|
|
compiler.Assemble(macro_assembler, node, data->capture_count, pattern);
|
|
|
|
if (FLAG_trace_irregexp) {
|
|
macro_assembler->PrintBlocks();
|
|
}
|
|
|
|
return result;
|
|
}
|
|
#endif // !defined(DART_PRECOMPILED_RUNTIME)
|
|
|
|
RegExpEngine::CompilationResult RegExpEngine::CompileBytecode(
|
|
RegExpCompileData* data,
|
|
const RegExp& regexp,
|
|
bool is_one_byte,
|
|
bool is_sticky,
|
|
Zone* zone) {
|
|
ASSERT(FLAG_interpret_irregexp);
|
|
const String& pattern = String::Handle(zone, regexp.pattern());
|
|
|
|
ASSERT(!regexp.IsNull());
|
|
ASSERT(!pattern.IsNull());
|
|
|
|
const bool is_global = regexp.flags().IsGlobal();
|
|
const bool is_unicode = regexp.flags().IsUnicode();
|
|
|
|
RegExpCompiler compiler(data->capture_count, is_one_byte);
|
|
|
|
// TODO(zerny): Frequency sampling is currently disabled because of several
|
|
// issues. We do not want to store subject strings in the regexp object since
|
|
// they might be long and we should not prevent their garbage collection.
|
|
// Passing them to this function explicitly does not help, since we must
|
|
// generate exactly the same IR for both the unoptimizing and optimizing
|
|
// pipelines (otherwise it gets confused when i.e. deopt id's differ).
|
|
// An option would be to store sampling results in the regexp object, but
|
|
// I'm not sure the performance gains are relevant enough.
|
|
|
|
// Wrap the body of the regexp in capture #0.
|
|
RegExpNode* captured_body =
|
|
RegExpCapture::ToNode(data->tree, 0, &compiler, compiler.accept());
|
|
|
|
RegExpNode* node = captured_body;
|
|
bool is_end_anchored = data->tree->IsAnchoredAtEnd();
|
|
bool is_start_anchored = data->tree->IsAnchoredAtStart();
|
|
intptr_t max_length = data->tree->max_match();
|
|
if (!is_start_anchored && !is_sticky) {
|
|
// Add a .*? at the beginning, outside the body capture, unless
|
|
// this expression is anchored at the beginning.
|
|
RegExpNode* loop_node = RegExpQuantifier::ToNode(
|
|
0, RegExpTree::kInfinity, false,
|
|
new (zone) RegExpCharacterClass('*', RegExpFlags()), &compiler,
|
|
captured_body, data->contains_anchor);
|
|
|
|
if (data->contains_anchor) {
|
|
// Unroll loop once, to take care of the case that might start
|
|
// at the start of input.
|
|
ChoiceNode* first_step_node = new (zone) ChoiceNode(2, zone);
|
|
first_step_node->AddAlternative(GuardedAlternative(captured_body));
|
|
first_step_node->AddAlternative(GuardedAlternative(new (zone) TextNode(
|
|
new (zone) RegExpCharacterClass('*', RegExpFlags()),
|
|
/*read_backwards=*/false, loop_node)));
|
|
node = first_step_node;
|
|
} else {
|
|
node = loop_node;
|
|
}
|
|
}
|
|
if (is_one_byte) {
|
|
node = node->FilterOneByte(RegExpCompiler::kMaxRecursion);
|
|
// Do it again to propagate the new nodes to places where they were not
|
|
// put because they had not been calculated yet.
|
|
if (node != NULL) {
|
|
node = node->FilterOneByte(RegExpCompiler::kMaxRecursion);
|
|
}
|
|
} else if (is_unicode && (is_global || is_sticky)) {
|
|
node = OptionallyStepBackToLeadSurrogate(&compiler, node, regexp.flags());
|
|
}
|
|
|
|
if (node == NULL) node = new (zone) EndNode(EndNode::BACKTRACK, zone);
|
|
data->node = node;
|
|
Analysis analysis(is_one_byte);
|
|
analysis.EnsureAnalyzed(node);
|
|
if (analysis.has_failed()) {
|
|
const char* error_message = analysis.error_message();
|
|
return CompilationResult(error_message);
|
|
}
|
|
|
|
// Bytecode regexp implementation.
|
|
|
|
ZoneGrowableArray<uint8_t> buffer(zone, 1024);
|
|
BytecodeRegExpMacroAssembler* macro_assembler =
|
|
new (zone) BytecodeRegExpMacroAssembler(&buffer, zone);
|
|
|
|
// Inserted here, instead of in Assembler, because it depends on information
|
|
// in the AST that isn't replicated in the Node structure.
|
|
static const intptr_t kMaxBacksearchLimit = 1024;
|
|
if (is_end_anchored && !is_start_anchored && !is_sticky &&
|
|
max_length < kMaxBacksearchLimit) {
|
|
macro_assembler->SetCurrentPositionFromEnd(max_length);
|
|
}
|
|
|
|
if (is_global) {
|
|
RegExpMacroAssembler::GlobalMode mode = RegExpMacroAssembler::GLOBAL;
|
|
if (data->tree->min_match() > 0) {
|
|
mode = RegExpMacroAssembler::GLOBAL_NO_ZERO_LENGTH_CHECK;
|
|
} else if (is_unicode) {
|
|
mode = RegExpMacroAssembler::GLOBAL_UNICODE;
|
|
}
|
|
macro_assembler->set_global_mode(mode);
|
|
}
|
|
|
|
RegExpEngine::CompilationResult result =
|
|
compiler.Assemble(macro_assembler, node, data->capture_count, pattern);
|
|
|
|
if (FLAG_trace_irregexp) {
|
|
macro_assembler->PrintBlocks();
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
static void CreateSpecializedFunction(Thread* thread,
|
|
Zone* zone,
|
|
const RegExp& regexp,
|
|
intptr_t specialization_cid,
|
|
bool sticky,
|
|
const Object& owner) {
|
|
const intptr_t kParamCount = RegExpMacroAssembler::kParamCount;
|
|
|
|
Function& fn =
|
|
Function::Handle(zone, Function::New(Symbols::ColonMatcher(),
|
|
RawFunction::kIrregexpFunction,
|
|
true, // Static.
|
|
false, // Not const.
|
|
false, // Not abstract.
|
|
false, // Not external.
|
|
false, // Not native.
|
|
owner, TokenPosition::kMinSource));
|
|
|
|
// TODO(zerny): Share these arrays between all irregexp functions.
|
|
fn.set_num_fixed_parameters(kParamCount);
|
|
fn.set_parameter_types(
|
|
Array::Handle(zone, Array::New(kParamCount, Heap::kOld)));
|
|
fn.set_parameter_names(
|
|
Array::Handle(zone, Array::New(kParamCount, Heap::kOld)));
|
|
fn.SetParameterTypeAt(RegExpMacroAssembler::kParamRegExpIndex,
|
|
Object::dynamic_type());
|
|
fn.SetParameterNameAt(RegExpMacroAssembler::kParamRegExpIndex,
|
|
Symbols::This());
|
|
fn.SetParameterTypeAt(RegExpMacroAssembler::kParamStringIndex,
|
|
Object::dynamic_type());
|
|
fn.SetParameterNameAt(RegExpMacroAssembler::kParamStringIndex,
|
|
Symbols::string_param());
|
|
fn.SetParameterTypeAt(RegExpMacroAssembler::kParamStartOffsetIndex,
|
|
Object::dynamic_type());
|
|
fn.SetParameterNameAt(RegExpMacroAssembler::kParamStartOffsetIndex,
|
|
Symbols::start_index_param());
|
|
fn.set_result_type(Type::Handle(zone, Type::ArrayType()));
|
|
|
|
// Cache the result.
|
|
regexp.set_function(specialization_cid, sticky, fn);
|
|
|
|
fn.SetRegExpData(regexp, specialization_cid, sticky);
|
|
fn.set_is_debuggable(false);
|
|
|
|
// The function is compiled lazily during the first call.
|
|
}
|
|
|
|
RawRegExp* RegExpEngine::CreateRegExp(Thread* thread,
|
|
const String& pattern,
|
|
RegExpFlags flags) {
|
|
Zone* zone = thread->zone();
|
|
const RegExp& regexp = RegExp::Handle(RegExp::New());
|
|
|
|
regexp.set_pattern(pattern);
|
|
regexp.set_flags(flags);
|
|
|
|
// TODO(zerny): We might want to use normal string searching algorithms
|
|
// for simple patterns.
|
|
regexp.set_is_complex();
|
|
regexp.set_is_global(); // All dart regexps are global.
|
|
|
|
if (!FLAG_interpret_irregexp) {
|
|
const Library& lib = Library::Handle(zone, Library::CoreLibrary());
|
|
const Class& owner =
|
|
Class::Handle(zone, lib.LookupClass(Symbols::RegExp()));
|
|
|
|
for (intptr_t cid = kOneByteStringCid; cid <= kExternalTwoByteStringCid;
|
|
cid++) {
|
|
CreateSpecializedFunction(thread, zone, regexp, cid, /*sticky=*/false,
|
|
owner);
|
|
CreateSpecializedFunction(thread, zone, regexp, cid, /*sticky=*/true,
|
|
owner);
|
|
}
|
|
}
|
|
|
|
return regexp.raw();
|
|
}
|
|
|
|
} // namespace dart
|