dart-sdk/runtime/vm/code_patcher_mips.cc
hausner@google.com b4f0bf5998 Fix debugger stub patching on x64 architecture
Instead of patching the entry in the object pool, patch the offset
into the pool at the call site.

SIMARM and SIMMIPS will have to be fixed the same way in a later change.

R=iposva@google.com

Review URL: https://codereview.chromium.org//131853006

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@31812 260f80e4-7a28-3924-810f-c04153c831b5
2014-01-14 23:27:13 +00:00

142 lines
4.2 KiB
C++

// Copyright (c) 2013, 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.
#include "vm/globals.h" // Needed here to get TARGET_ARCH_MIPS.
#if defined(TARGET_ARCH_MIPS)
#include "vm/code_patcher.h"
#include "vm/instructions.h"
#include "vm/object.h"
namespace dart {
RawArray* CodePatcher::GetClosureArgDescAt(uword return_address,
const Code& code) {
ASSERT(code.ContainsInstructionAt(return_address));
CallPattern call(return_address, code);
return call.ClosureArgumentsDescriptor();
}
uword CodePatcher::GetStaticCallTargetAt(uword return_address,
const Code& code) {
ASSERT(code.ContainsInstructionAt(return_address));
CallPattern call(return_address, code);
return call.TargetAddress();
}
void CodePatcher::PatchStaticCallAt(uword return_address,
const Code& code,
uword new_target) {
ASSERT(code.ContainsInstructionAt(return_address));
CallPattern call(return_address, code);
call.SetTargetAddress(new_target);
}
void CodePatcher::PatchInstanceCallAt(uword return_address,
const Code& code,
uword new_target) {
ASSERT(code.ContainsInstructionAt(return_address));
CallPattern call(return_address, code);
call.SetTargetAddress(new_target);
}
int32_t CodePatcher::GetPoolOffsetAt(uword return_address) {
UNIMPLEMENTED();
return 0;
}
void CodePatcher::SetPoolOffsetAt(uword return_address, int32_t offset) {
UNIMPLEMENTED();
}
void CodePatcher::InsertCallAt(uword start, uword target) {
// The inserted call should not overlap the lazy deopt jump code.
ASSERT(start + CallPattern::kFixedLengthInBytes <= target);
CallPattern::InsertAt(start, target);
}
uword CodePatcher::GetInstanceCallAt(uword return_address,
const Code& code,
ICData* ic_data) {
ASSERT(code.ContainsInstructionAt(return_address));
CallPattern call(return_address, code);
if (ic_data != NULL) {
*ic_data = call.IcData();
}
return call.TargetAddress();
}
intptr_t CodePatcher::InstanceCallSizeInBytes() {
// The instance call instruction sequence has a variable size on MIPS.
UNREACHABLE();
return 0;
}
RawFunction* CodePatcher::GetUnoptimizedStaticCallAt(
uword return_address, const Code& code, ICData* ic_data_result) {
ASSERT(code.ContainsInstructionAt(return_address));
CallPattern static_call(return_address, code);
ICData& ic_data = ICData::Handle();
ic_data ^= static_call.IcData();
if (ic_data_result != NULL) {
*ic_data_result = ic_data.raw();
}
return ic_data.GetTargetAt(0);
}
// This class pattern matches on a load from the object pool. Loading on
// MIPS is complicated because it can take four possible different forms.
// We match backwards from the end of the sequence so we can reuse the code
// for matching object pool loads at calls.
class EdgeCounter : public ValueObject {
public:
EdgeCounter(uword pc, const Code& code)
: end_(pc - kAdjust), object_pool_(Array::Handle(code.ObjectPool())) {
// An IsValid predicate is complicated and duplicates the code in the
// decoding function. Instead we rely on decoding the pattern which
// will assert partial validity.
}
RawObject* edge_counter() const {
Register ignored;
intptr_t index;
InstructionPattern::DecodeLoadWordFromPool(end_, &ignored, &index);
ASSERT(ignored == T0);
return object_pool_.At(index);
}
private:
// The object pool load is followed by the fixed-size edge counter
// incrementing code:
// lw r9, 11(r8)
// addiu r9, r9, 2
// sw r9, 11(r8)
static const intptr_t kAdjust = 3 * Instr::kInstrSize;
uword end_;
const Array& object_pool_;
};
RawObject* CodePatcher::GetEdgeCounterAt(uword pc, const Code& code) {
ASSERT(code.ContainsInstructionAt(pc));
EdgeCounter counter(pc, code);
return counter.edge_counter();
}
} // namespace dart
#endif // defined TARGET_ARCH_MIPS