FTLSlowPathCall.cpp [plain text]
#include "config.h"
#include "FTLSlowPathCall.h"
#if ENABLE(FTL_JIT)
#include "CCallHelpers.h"
#include "FTLState.h"
#include "FTLThunks.h"
#include "GPRInfo.h"
#include "JSCInlines.h"
namespace JSC { namespace FTL {
static const size_t wordSize = 8;
SlowPathCallContext::SlowPathCallContext(
RegisterSet usedRegisters, CCallHelpers& jit, unsigned numArgs, GPRReg returnRegister)
: m_jit(jit)
, m_numArgs(numArgs)
, m_returnRegister(returnRegister)
{
usedRegisters.exclude(RegisterSet::stackRegisters());
usedRegisters.exclude(RegisterSet::reservedHardwareRegisters());
usedRegisters.exclude(RegisterSet::calleeSaveRegisters());
if (m_returnRegister != InvalidGPRReg)
usedRegisters.clear(m_returnRegister);
size_t stackBytesNeededForReturnAddress = wordSize;
m_offsetToSavingArea =
(std::max(m_numArgs, NUMBER_OF_ARGUMENT_REGISTERS) - NUMBER_OF_ARGUMENT_REGISTERS) * wordSize;
for (unsigned i = std::min(NUMBER_OF_ARGUMENT_REGISTERS, numArgs); i--;)
m_argumentRegisters.set(GPRInfo::toArgumentRegister(i));
m_callingConventionRegisters.merge(m_argumentRegisters);
if (returnRegister != InvalidGPRReg)
m_callingConventionRegisters.set(GPRInfo::returnValueGPR);
m_callingConventionRegisters.filter(usedRegisters);
unsigned numberOfCallingConventionRegisters =
m_callingConventionRegisters.numberOfSetRegisters();
size_t offsetToThunkSavingArea =
m_offsetToSavingArea +
numberOfCallingConventionRegisters * wordSize;
m_stackBytesNeeded =
offsetToThunkSavingArea +
stackBytesNeededForReturnAddress +
(usedRegisters.numberOfSetRegisters() - numberOfCallingConventionRegisters) * wordSize;
m_stackBytesNeeded = (m_stackBytesNeeded + stackAlignmentBytes() - 1) & ~(stackAlignmentBytes() - 1);
m_jit.subPtr(CCallHelpers::TrustedImm32(m_stackBytesNeeded), CCallHelpers::stackPointerRegister);
m_thunkSaveSet = usedRegisters;
unsigned stackIndex = 0;
for (unsigned i = GPRInfo::numberOfRegisters; i--;) {
GPRReg reg = GPRInfo::toRegister(i);
if (!m_callingConventionRegisters.get(reg))
continue;
m_jit.storePtr(reg, CCallHelpers::Address(CCallHelpers::stackPointerRegister, m_offsetToSavingArea + (stackIndex++) * wordSize));
m_thunkSaveSet.clear(reg);
}
m_offset = offsetToThunkSavingArea;
}
SlowPathCallContext::~SlowPathCallContext()
{
if (m_returnRegister != InvalidGPRReg)
m_jit.move(GPRInfo::returnValueGPR, m_returnRegister);
unsigned stackIndex = 0;
for (unsigned i = GPRInfo::numberOfRegisters; i--;) {
GPRReg reg = GPRInfo::toRegister(i);
if (!m_callingConventionRegisters.get(reg))
continue;
m_jit.loadPtr(CCallHelpers::Address(CCallHelpers::stackPointerRegister, m_offsetToSavingArea + (stackIndex++) * wordSize), reg);
}
m_jit.addPtr(CCallHelpers::TrustedImm32(m_stackBytesNeeded), CCallHelpers::stackPointerRegister);
}
SlowPathCallKey SlowPathCallContext::keyWithTarget(void* callTarget) const
{
return SlowPathCallKey(m_thunkSaveSet, callTarget, m_argumentRegisters, m_offset);
}
SlowPathCall SlowPathCallContext::makeCall(VM& vm, void* callTarget)
{
SlowPathCall result = SlowPathCall(m_jit.call(), keyWithTarget(callTarget));
m_jit.addLinkTask(
[result, &vm] (LinkBuffer& linkBuffer) {
MacroAssemblerCodeRef thunk =
vm.ftlThunks->getSlowPathCallThunk(result.key());
linkBuffer.link(result.call(), CodeLocationLabel(thunk.code()));
});
return result;
}
CallSiteIndex callSiteIndexForCodeOrigin(State& state, CodeOrigin codeOrigin)
{
if (codeOrigin)
return state.jitCode->common.addCodeOrigin(codeOrigin);
return CallSiteIndex();
}
} }
#endif // ENABLE(FTL_JIT)