dart-sdk/runtime/vm/instructions_x64.cc

68 lines
2.2 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.
#include "vm/globals.h" // Needed here to get TARGET_ARCH_X64.
#if defined(TARGET_ARCH_X64)
#include "vm/instructions.h"
#include "vm/instructions_x64.h"
#include "vm/cpu.h"
#include "vm/constants_x64.h"
#include "vm/object.h"
namespace dart {
bool DecodeLoadObjectFromPoolOrThread(uword pc, const Code& code, Object* obj) {
ASSERT(code.ContainsInstructionAt(pc));
uint8_t* bytes = reinterpret_cast<uint8_t*>(pc);
COMPILE_ASSERT(PP == R15);
if ((bytes[0] == 0x49) || (bytes[0] == 0x4d)) {
if ((bytes[1] == 0x8b) || (bytes[1] == 0x3b)) { // movq, cmpq
if ((bytes[2] & 0xc7) == (0x80 | (PP & 7))) { // [r15+disp32]
intptr_t index = IndexFromPPLoad(pc + 3);
const ObjectPool& pool = ObjectPool::Handle(code.object_pool());
if (pool.InfoAt(index) == ObjectPool::kTaggedObject) {
*obj = pool.ObjectAt(index);
return true;
}
}
if ((bytes[2] & 0xc7) == (0x40 | (PP & 7))) { // [r15+disp8]
intptr_t index = IndexFromPPLoadDisp8(pc + 3);
const ObjectPool& pool = ObjectPool::Handle(code.object_pool());
if (pool.InfoAt(index) == ObjectPool::kTaggedObject) {
*obj = pool.ObjectAt(index);
return true;
}
}
}
}
COMPILE_ASSERT(THR == R14);
if ((bytes[0] == 0x49) || (bytes[0] == 0x4d)) {
if ((bytes[1] == 0x8b) || (bytes[1] == 0x3b)) { // movq, cmpq
if ((bytes[2] & 0xc7) == (0x80 | (THR & 7))) { // [r14+disp32]
int32_t offset = *reinterpret_cast<int32_t*>(pc + 3);
return Thread::ObjectAtOffset(offset, obj);
}
if ((bytes[2] & 0xc7) == (0x40 | (THR & 7))) { // [r14+disp8]
uint8_t offset = *reinterpret_cast<uint8_t*>(pc + 3);
return Thread::ObjectAtOffset(offset, obj);
}
}
}
if (((bytes[0] == 0x41) && (bytes[1] == 0xff) && (bytes[2] == 0x76))) {
// push [r14+disp8]
uint8_t offset = *reinterpret_cast<uint8_t*>(pc + 3);
return Thread::ObjectAtOffset(offset, obj);
}
return false;
}
} // namespace dart
#endif // defined TARGET_ARCH_X64