void JIT::compileLoadVarargs(Instruction* instruction)
{
int thisValue = instruction[3].u.operand;
int arguments = instruction[4].u.operand;
int firstFreeRegister = instruction[5].u.operand;
JumpList slowCase;
JumpList end;
bool canOptimize = m_codeBlock->usesArguments()
&& arguments == m_codeBlock->argumentsRegister().offset()
&& !m_codeBlock->symbolTable()->slowArguments();
if (canOptimize) {
emitGetVirtualRegister(arguments, regT0);
slowCase.append(branch64(NotEqual, regT0, TrustedImm64(JSValue::encode(JSValue()))));
emitGetFromCallFrameHeader32(JSStack::ArgumentCount, regT0);
slowCase.append(branch32(Above, regT0, TrustedImm32(Arguments::MaxArguments + 1)));
// regT0: argumentCountIncludingThis
move(regT0, regT1);
neg64(regT1);
add64(TrustedImm32(firstFreeRegister - JSStack::CallFrameHeaderSize), regT1);
lshift64(TrustedImm32(3), regT1);
addPtr(callFrameRegister, regT1);
// regT1: newCallFrame
slowCase.append(branchPtr(Above, AbsoluteAddress(m_vm->addressOfJSStackLimit()), regT1));
// Initialize ArgumentCount.
store32(regT0, Address(regT1, JSStack::ArgumentCount * static_cast<int>(sizeof(Register)) + OBJECT_OFFSETOF(EncodedValueDescriptor, asBits.payload)));
// Initialize 'this'.
emitGetVirtualRegister(thisValue, regT2);
store64(regT2, Address(regT1, CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register))));
// Copy arguments.
signExtend32ToPtr(regT0, regT0);
end.append(branchSub64(Zero, TrustedImm32(1), regT0));
// regT0: argumentCount
Label copyLoop = label();
load64(BaseIndex(callFrameRegister, regT0, TimesEight, CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register))), regT2);
store64(regT2, BaseIndex(regT1, regT0, TimesEight, CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register))));
branchSub64(NonZero, TrustedImm32(1), regT0).linkTo(copyLoop, this);
end.append(jump());
}
if (canOptimize)
slowCase.link(this);
emitGetVirtualRegister(thisValue, regT0);
emitGetVirtualRegister(arguments, regT1);
callOperation(operationLoadVarargs, regT0, regT1, firstFreeRegister);
move(returnValueGPR, regT1);
if (canOptimize)
end.link(this);
}
void JIT::compileLoadVarargs(Instruction* instruction)
{
int thisValue = instruction[2].u.operand;
int arguments = instruction[3].u.operand;
int firstFreeRegister = instruction[4].u.operand;
killLastResultRegister();
JumpList slowCase;
JumpList end;
if (m_codeBlock->usesArguments() && arguments == m_codeBlock->argumentsRegister()) {
emitGetVirtualRegister(arguments, regT0);
slowCase.append(branchPtr(NotEqual, regT0, TrustedImmPtr(JSValue::encode(JSValue()))));
emitGetFromCallFrameHeader32(RegisterFile::ArgumentCount, regT0);
slowCase.append(branch32(Above, regT0, TrustedImm32(Arguments::MaxArguments + 1)));
// regT0: argumentCountIncludingThis
move(regT0, regT1);
add32(TrustedImm32(firstFreeRegister + RegisterFile::CallFrameHeaderSize), regT1);
lshift32(TrustedImm32(3), regT1);
addPtr(callFrameRegister, regT1);
// regT1: newCallFrame
slowCase.append(branchPtr(Below, AbsoluteAddress(m_globalData->interpreter->registerFile().addressOfEnd()), regT1));
// Initialize ArgumentCount.
emitFastArithReTagImmediate(regT0, regT2);
storePtr(regT2, Address(regT1, RegisterFile::ArgumentCount * static_cast<int>(sizeof(Register))));
// Initialize 'this'.
emitGetVirtualRegister(thisValue, regT2);
storePtr(regT2, Address(regT1, CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register))));
// Copy arguments.
neg32(regT0);
signExtend32ToPtr(regT0, regT0);
end.append(branchAddPtr(Zero, Imm32(1), regT0));
// regT0: -argumentCount
Label copyLoop = label();
loadPtr(BaseIndex(callFrameRegister, regT0, TimesEight, CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register))), regT2);
storePtr(regT2, BaseIndex(regT1, regT0, TimesEight, CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register))));
branchAddPtr(NonZero, Imm32(1), regT0).linkTo(copyLoop, this);
end.append(jump());
}
if (m_codeBlock->usesArguments() && arguments == m_codeBlock->argumentsRegister())
slowCase.link(this);
JITStubCall stubCall(this, cti_op_load_varargs);
stubCall.addArgument(thisValue, regT0);
stubCall.addArgument(arguments, regT0);
stubCall.addArgument(Imm32(firstFreeRegister));
stubCall.call(regT1);
if (m_codeBlock->usesArguments() && arguments == m_codeBlock->argumentsRegister())
end.link(this);
}
void JIT::compileLoadVarargs(Instruction* instruction)
{
int thisValue = instruction[2].u.operand;
int arguments = instruction[3].u.operand;
int firstFreeRegister = instruction[4].u.operand;
JumpList slowCase;
JumpList end;
if (m_codeBlock->usesArguments() && arguments == m_codeBlock->argumentsRegister()) {
emitLoadTag(arguments, regT1);
slowCase.append(branch32(NotEqual, regT1, TrustedImm32(JSValue::EmptyValueTag)));
load32(payloadFor(RegisterFile::ArgumentCount), regT2);
slowCase.append(branch32(Above, regT2, TrustedImm32(Arguments::MaxArguments + 1)));
// regT2: argumentCountIncludingThis
move(regT2, regT3);
add32(TrustedImm32(firstFreeRegister + RegisterFile::CallFrameHeaderSize), regT3);
lshift32(TrustedImm32(3), regT3);
addPtr(callFrameRegister, regT3);
// regT3: newCallFrame
slowCase.append(branchPtr(Below, AbsoluteAddress(m_globalData->interpreter->registerFile().addressOfEnd()), regT3));
// Initialize ArgumentCount.
store32(regT2, payloadFor(RegisterFile::ArgumentCount, regT3));
// Initialize 'this'.
emitLoad(thisValue, regT1, regT0);
store32(regT0, Address(regT3, OBJECT_OFFSETOF(JSValue, u.asBits.payload) + (CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register)))));
store32(regT1, Address(regT3, OBJECT_OFFSETOF(JSValue, u.asBits.tag) + (CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register)))));
// Copy arguments.
neg32(regT2);
end.append(branchAdd32(Zero, TrustedImm32(1), regT2));
// regT2: -argumentCount;
Label copyLoop = label();
load32(BaseIndex(callFrameRegister, regT2, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.payload) +(CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register)))), regT0);
load32(BaseIndex(callFrameRegister, regT2, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.tag) +(CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register)))), regT1);
store32(regT0, BaseIndex(regT3, regT2, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.payload) +(CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register)))));
store32(regT1, BaseIndex(regT3, regT2, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.tag) +(CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register)))));
branchAdd32(NonZero, TrustedImm32(1), regT2).linkTo(copyLoop, this);
end.append(jump());
}
if (m_codeBlock->usesArguments() && arguments == m_codeBlock->argumentsRegister())
slowCase.link(this);
JITStubCall stubCall(this, cti_op_load_varargs);
stubCall.addArgument(thisValue);
stubCall.addArgument(arguments);
stubCall.addArgument(Imm32(firstFreeRegister));
stubCall.call(regT3);
if (m_codeBlock->usesArguments() && arguments == m_codeBlock->argumentsRegister())
end.link(this);
}
void JIT::compileLoadVarargs(Instruction* instruction)
{
int thisValue = instruction[3].u.operand;
int arguments = instruction[4].u.operand;
int firstFreeRegister = instruction[5].u.operand;
JumpList slowCase;
JumpList end;
bool canOptimize = m_codeBlock->usesArguments()
&& VirtualRegister(arguments) == m_codeBlock->argumentsRegister()
&& !m_codeBlock->symbolTable()->slowArguments();
if (canOptimize) {
emitLoadTag(arguments, regT1);
slowCase.append(branch32(NotEqual, regT1, TrustedImm32(JSValue::EmptyValueTag)));
load32(payloadFor(JSStack::ArgumentCount), regT2);
slowCase.append(branch32(Above, regT2, TrustedImm32(Arguments::MaxArguments + 1)));
// regT2: argumentCountIncludingThis
move(regT2, regT3);
neg32(regT3);
add32(TrustedImm32(firstFreeRegister - JSStack::CallFrameHeaderSize), regT3);
lshift32(TrustedImm32(3), regT3);
addPtr(callFrameRegister, regT3);
// regT3: newCallFrame
slowCase.append(branchPtr(Above, AbsoluteAddress(m_vm->interpreter->stack().addressOfEnd()), regT3));
// Initialize ArgumentCount.
store32(regT2, payloadFor(JSStack::ArgumentCount, regT3));
// Initialize 'this'.
emitLoad(thisValue, regT1, regT0);
store32(regT0, Address(regT3, OBJECT_OFFSETOF(JSValue, u.asBits.payload) + (CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register)))));
store32(regT1, Address(regT3, OBJECT_OFFSETOF(JSValue, u.asBits.tag) + (CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register)))));
// Copy arguments.
end.append(branchSub32(Zero, TrustedImm32(1), regT2));
// regT2: argumentCount;
Label copyLoop = label();
load32(BaseIndex(callFrameRegister, regT2, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.payload) +(CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register)))), regT0);
load32(BaseIndex(callFrameRegister, regT2, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.tag) +(CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register)))), regT1);
store32(regT0, BaseIndex(regT3, regT2, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.payload) +(CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register)))));
store32(regT1, BaseIndex(regT3, regT2, TimesEight, OBJECT_OFFSETOF(JSValue, u.asBits.tag) +(CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register)))));
branchSub32(NonZero, TrustedImm32(1), regT2).linkTo(copyLoop, this);
end.append(jump());
}
if (canOptimize)
slowCase.link(this);
emitLoad(thisValue, regT1, regT0);
emitLoad(arguments, regT3, regT2);
callOperation(operationLoadVarargs, regT1, regT0, regT3, regT2, firstFreeRegister);
move(returnValueRegister, regT3);
if (canOptimize)
end.link(this);
}
void JIT::compileLoadVarargs(Instruction* instruction)
{
int thisValue = instruction[3].u.operand;
int arguments = instruction[4].u.operand;
int firstFreeRegister = instruction[5].u.operand;
int firstVarArgOffset = instruction[6].u.operand;
JumpList slowCase;
JumpList end;
bool canOptimize = m_codeBlock->usesArguments()
&& arguments == m_codeBlock->argumentsRegister().offset()
&& !m_codeBlock->symbolTable()->slowArguments();
if (canOptimize) {
emitGetVirtualRegister(arguments, regT0);
slowCase.append(branch64(NotEqual, regT0, TrustedImm64(JSValue::encode(JSValue()))));
emitGetFromCallFrameHeader32(JSStack::ArgumentCount, regT0);
if (firstVarArgOffset) {
Jump sufficientArguments = branch32(GreaterThan, regT0, TrustedImm32(firstVarArgOffset + 1));
move(TrustedImm32(1), regT0);
Jump endVarArgs = jump();
sufficientArguments.link(this);
sub32(TrustedImm32(firstVarArgOffset), regT0);
endVarArgs.link(this);
}
slowCase.append(branch32(Above, regT0, TrustedImm32(Arguments::MaxArguments + 1)));
// regT0: argumentCountIncludingThis
move(regT0, regT1);
add64(TrustedImm32(-firstFreeRegister + JSStack::CallFrameHeaderSize), regT1);
// regT1 now has the required frame size in Register units
// Round regT1 to next multiple of stackAlignmentRegisters()
add64(TrustedImm32(stackAlignmentRegisters() - 1), regT1);
and64(TrustedImm32(~(stackAlignmentRegisters() - 1)), regT1);
neg64(regT1);
lshift64(TrustedImm32(3), regT1);
addPtr(callFrameRegister, regT1);
// regT1: newCallFrame
slowCase.append(branchPtr(Above, AbsoluteAddress(m_vm->addressOfStackLimit()), regT1));
// Initialize ArgumentCount.
store32(regT0, Address(regT1, JSStack::ArgumentCount * static_cast<int>(sizeof(Register)) + OBJECT_OFFSETOF(EncodedValueDescriptor, asBits.payload)));
// Initialize 'this'.
emitGetVirtualRegister(thisValue, regT2);
store64(regT2, Address(regT1, CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register))));
// Copy arguments.
signExtend32ToPtr(regT0, regT0);
end.append(branchSub64(Zero, TrustedImm32(1), regT0));
// regT0: argumentCount
Label copyLoop = label();
load64(BaseIndex(callFrameRegister, regT0, TimesEight, (CallFrame::thisArgumentOffset() + firstVarArgOffset) * static_cast<int>(sizeof(Register))), regT2);
store64(regT2, BaseIndex(regT1, regT0, TimesEight, CallFrame::thisArgumentOffset() * static_cast<int>(sizeof(Register))));
branchSub64(NonZero, TrustedImm32(1), regT0).linkTo(copyLoop, this);
end.append(jump());
}
if (canOptimize)
slowCase.link(this);
emitGetVirtualRegister(arguments, regT1);
callOperation(operationSizeFrameForVarargs, regT1, firstFreeRegister, firstVarArgOffset);
move(returnValueGPR, stackPointerRegister);
emitGetVirtualRegister(thisValue, regT1);
emitGetVirtualRegister(arguments, regT2);
callOperation(operationLoadVarargs, returnValueGPR, regT1, regT2, firstVarArgOffset);
move(returnValueGPR, regT1);
if (canOptimize)
end.link(this);
addPtr(TrustedImm32(sizeof(CallerFrameAndPC)), regT1, stackPointerRegister);
}
void JITCompiler::compileFunction()
{
SamplingRegion samplingRegion("DFG Backend");
setStartOfCode();
compileEntry();
// === Function header code generation ===
// This is the main entry point, without performing an arity check.
// If we needed to perform an arity check we will already have moved the return address,
// so enter after this.
Label fromArityCheck(this);
// Plant a check that sufficient space is available in the JSStack.
addPtr(TrustedImm32(virtualRegisterForLocal(m_graph.requiredRegisterCountForExecutionAndExit() - 1).offset() * sizeof(Register)), GPRInfo::callFrameRegister, GPRInfo::regT1);
Jump stackOverflow = branchPtr(Above, AbsoluteAddress(m_vm->addressOfStackLimit()), GPRInfo::regT1);
// Move the stack pointer down to accommodate locals
addPtr(TrustedImm32(m_graph.stackPointerOffset() * sizeof(Register)), GPRInfo::callFrameRegister, stackPointerRegister);
checkStackPointerAlignment();
// === Function body code generation ===
m_speculative = adoptPtr(new SpeculativeJIT(*this));
compileBody();
setEndOfMainPath();
// === Function footer code generation ===
//
// Generate code to perform the stack overflow handling (if the stack check in
// the function header fails), and generate the entry point with arity check.
//
// Generate the stack overflow handling; if the stack check in the function head fails,
// we need to call out to a helper function to throw the StackOverflowError.
stackOverflow.link(this);
emitStoreCodeOrigin(CodeOrigin(0));
if (maxFrameExtentForSlowPathCall)
addPtr(TrustedImm32(-maxFrameExtentForSlowPathCall), stackPointerRegister);
m_speculative->callOperationWithCallFrameRollbackOnException(operationThrowStackOverflowError, m_codeBlock);
// The fast entry point into a function does not check the correct number of arguments
// have been passed to the call (we only use the fast entry point where we can statically
// determine the correct number of arguments have been passed, or have already checked).
// In cases where an arity check is necessary, we enter here.
// FIXME: change this from a cti call to a DFG style operation (normal C calling conventions).
m_arityCheck = label();
compileEntry();
load32(AssemblyHelpers::payloadFor((VirtualRegister)JSStack::ArgumentCount), GPRInfo::regT1);
branch32(AboveOrEqual, GPRInfo::regT1, TrustedImm32(m_codeBlock->numParameters())).linkTo(fromArityCheck, this);
emitStoreCodeOrigin(CodeOrigin(0));
if (maxFrameExtentForSlowPathCall)
addPtr(TrustedImm32(-maxFrameExtentForSlowPathCall), stackPointerRegister);
m_speculative->callOperationWithCallFrameRollbackOnException(m_codeBlock->m_isConstructor ? operationConstructArityCheck : operationCallArityCheck, GPRInfo::regT0);
if (maxFrameExtentForSlowPathCall)
addPtr(TrustedImm32(maxFrameExtentForSlowPathCall), stackPointerRegister);
branchTest32(Zero, GPRInfo::regT0).linkTo(fromArityCheck, this);
emitStoreCodeOrigin(CodeOrigin(0));
move(TrustedImmPtr(m_vm->arityCheckFailReturnThunks->returnPCsFor(*m_vm, m_codeBlock->numParameters())), GPRInfo::regT5);
loadPtr(BaseIndex(GPRInfo::regT5, GPRInfo::regT0, timesPtr()), GPRInfo::regT5);
m_callArityFixup = call();
jump(fromArityCheck);
// Generate slow path code.
m_speculative->runSlowPathGenerators();
compileExceptionHandlers();
linkOSRExits();
// Create OSR entry trampolines if necessary.
m_speculative->createOSREntries();
setEndOfCode();
}
