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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "jit/arm/Assembler-arm.h"
#include "jit/Bailouts.h"
#include "jit/JitFrames.h"
#include "jit/JitRuntime.h"
#include "jit/SafepointIndex.h"
#include "jit/ScriptFromCalleeToken.h"
#include "vm/JSContext.h"
#include "vm/Realm.h"
#include "vm/JSScript-inl.h"
using namespace js;
using namespace js::jit;
namespace js {
namespace jit {
class BailoutStack {
uintptr_t frameClassId_;
// This is pushed in the bailout handler. Both entry points into the handler
// inserts their own value int lr, which is then placed onto the stack along
// with frameClassId_ above. This should be migrated to ip.
public:
union {
uintptr_t frameSize_;
uintptr_t tableOffset_;
};
protected: // Silence Clang warning about unused private fields.
RegisterDump::FPUArray fpregs_;
RegisterDump::GPRArray regs_;
uintptr_t snapshotOffset_;
uintptr_t padding_;
public:
FrameSizeClass frameClass() const {
return FrameSizeClass::FromClass(frameClassId_);
}
uintptr_t tableOffset() const {
MOZ_ASSERT(frameClass() != FrameSizeClass::None());
return tableOffset_;
}
uint32_t frameSize() const {
if (frameClass() == FrameSizeClass::None()) {
return frameSize_;
}
return frameClass().frameSize();
}
MachineState machine() { return MachineState::FromBailout(regs_, fpregs_); }
SnapshotOffset snapshotOffset() const {
MOZ_ASSERT(frameClass() == FrameSizeClass::None());
return snapshotOffset_;
}
uint8_t* parentStackPointer() const {
if (frameClass() == FrameSizeClass::None()) {
return (uint8_t*)this + sizeof(BailoutStack);
}
return (uint8_t*)this + offsetof(BailoutStack, snapshotOffset_);
}
};
// Make sure the compiler doesn't add extra padding.
static_assert((sizeof(BailoutStack) % 8) == 0,
"BailoutStack should be 8-byte aligned.");
} // namespace jit
} // namespace js
BailoutFrameInfo::BailoutFrameInfo(const JitActivationIterator& activations,
BailoutStack* bailout)
: machine_(bailout->machine()) {
uint8_t* sp = bailout->parentStackPointer();
framePointer_ = sp + bailout->frameSize();
topFrameSize_ = framePointer_ - sp;
JSScript* script =
ScriptFromCalleeToken(((JitFrameLayout*)framePointer_)->calleeToken());
JitActivation* activation = activations.activation()->asJit();
topIonScript_ = script->ionScript();
attachOnJitActivation(activations);
if (bailout->frameClass() == FrameSizeClass::None()) {
snapshotOffset_ = bailout->snapshotOffset();
return;
}
// Compute the snapshot offset from the bailout ID.
JSRuntime* rt = activation->compartment()->runtimeFromMainThread();
TrampolinePtr code = rt->jitRuntime()->getBailoutTable(bailout->frameClass());
#ifdef DEBUG
uint32_t tableSize =
rt->jitRuntime()->getBailoutTableSize(bailout->frameClass());
#endif
uintptr_t tableOffset = bailout->tableOffset();
uintptr_t tableStart =
reinterpret_cast<uintptr_t>(Assembler::BailoutTableStart(code.value));
MOZ_ASSERT(tableOffset >= tableStart && tableOffset < tableStart + tableSize);
MOZ_ASSERT((tableOffset - tableStart) % BAILOUT_TABLE_ENTRY_SIZE == 0);
uint32_t bailoutId =
((tableOffset - tableStart) / BAILOUT_TABLE_ENTRY_SIZE) - 1;
MOZ_ASSERT(bailoutId < BAILOUT_TABLE_SIZE);
snapshotOffset_ = topIonScript_->bailoutToSnapshot(bailoutId);
}
BailoutFrameInfo::BailoutFrameInfo(const JitActivationIterator& activations,
InvalidationBailoutStack* bailout)
: machine_(bailout->machine()) {
framePointer_ = (uint8_t*)bailout->fp();
topFrameSize_ = framePointer_ - bailout->sp();
topIonScript_ = bailout->ionScript();
attachOnJitActivation(activations);
uint8_t* returnAddressToFp_ = bailout->osiPointReturnAddress();
const OsiIndex* osiIndex = topIonScript_->getOsiIndex(returnAddressToFp_);
snapshotOffset_ = osiIndex->snapshotOffset();
}