dart-sdk/runtime/vm/code_patcher.h
fschneider@google.com 4201900778 VM: Small generated code size improvements on x64.
Addtional cleanup in code_patcher on all platforms.

R=zra@google.com

Review URL: https://codereview.chromium.org//829133006

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@42700 260f80e4-7a28-3924-810f-c04153c831b5
2015-01-08 16:42:05 +00:00

98 lines
3.2 KiB
C++

// Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
// Class for patching compiled code.
#ifndef VM_CODE_PATCHER_H_
#define VM_CODE_PATCHER_H_
#include "vm/allocation.h"
namespace dart {
// Forward declaration.
class Array;
class Code;
class ExternalLabel;
class Function;
class ICData;
class RawArray;
class RawFunction;
class RawICData;
class RawObject;
class String;
// Stack-allocated class to create a scope where the specified region
// [address, addresss + size] has write access enabled. This is used
// when patching generated code. Access is reset to read-execute in
// the destructor of this scope.
class WritableInstructionsScope : public ValueObject {
public:
WritableInstructionsScope(uword address, intptr_t size);
~WritableInstructionsScope();
private:
const uword address_;
const intptr_t size_;
};
class CodePatcher : public AllStatic {
public:
// Dart static calls have a distinct, machine-dependent code pattern.
// Patch static call before return_address in given code to the new target.
static void PatchStaticCallAt(uword return_address,
const Code& code,
uword new_target_address);
// Patch instance call before return_address in given code to the new target.
static void PatchInstanceCallAt(uword return_address,
const Code& code,
uword new_target_address);
// Patch entry point with a jump as specified in the code's patch region.
static void PatchEntry(const Code& code);
// Restore entry point with original code (i.e., before patching).
static void RestoreEntry(const Code& code);
// Has the entry been patched?
static bool IsEntryPatched(const Code& code);
// Returns true if the code can be patched with a jump at beginning (checks
// that there are no conflicts with object pointers). Used in ASSERTs.
static bool CodeIsPatchable(const Code& code);
// Return the target address of the static call before return_address
// in given code.
static uword GetStaticCallTargetAt(uword return_address, const Code& code);
// Get instance call information. Returns the call target and sets each
// of the output parameters ic_data and arguments_descriptor if they are
// non-NULL.
static uword GetInstanceCallAt(uword return_address,
const Code& code,
ICData* ic_data);
// Return target of an unoptimized static call and its ICData object
// (calls target via a stub).
static RawFunction* GetUnoptimizedStaticCallAt(uword return_address,
const Code& code,
ICData* ic_data);
static intptr_t InstanceCallSizeInBytes();
static void InsertCallAt(uword start, uword target);
static RawObject* GetEdgeCounterAt(uword pc, const Code& code);
static int32_t GetPoolOffsetAt(uword return_address);
static void SetPoolOffsetAt(uword return_address, int32_t offset);
};
} // namespace dart
#endif // VM_CODE_PATCHER_H_