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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
#include "mozilla/MathAlgorithms.h"
#include "jit/Bailouts.h"
#include "jit/BaselineFrame.h"
#include "jit/BaselineJIT.h"
#include "jit/CalleeToken.h"
#include "jit/JitFrames.h"
#include "jit/JitRuntime.h"
#include "jit/JitSpewer.h"
#include "jit/PerfSpewer.h"
#include "jit/VMFunctions.h"
#include "jit/x86/SharedICHelpers-x86.h"
#include "vm/JitActivation.h" // js::jit::JitActivation
#include "vm/JSContext.h"
#include "vm/Realm.h"
#ifdef MOZ_VTUNE
# include "vtune/VTuneWrapper.h"
#endif
#include "jit/MacroAssembler-inl.h"
#include "vm/JSScript-inl.h"
using mozilla::IsPowerOfTwo;
using namespace js;
using namespace js::jit;
// All registers to save and restore. This includes the stack pointer, since we
// use the ability to reference register values on the stack by index.
static const LiveRegisterSet AllRegs =
LiveRegisterSet(GeneralRegisterSet(Registers::AllMask),
FloatRegisterSet(FloatRegisters::AllMask));
enum EnterJitEbpArgumentOffset {
ARG_JITCODE = 2 * sizeof(void*),
ARG_ARGC = 3 * sizeof(void*),
ARG_ARGV = 4 * sizeof(void*),
ARG_STACKFRAME = 5 * sizeof(void*),
ARG_CALLEETOKEN = 6 * sizeof(void*),
ARG_SCOPECHAIN = 7 * sizeof(void*),
ARG_STACKVALUES = 8 * sizeof(void*),
ARG_RESULT = 9 * sizeof(void*)
};
// Generates a trampoline for calling Jit compiled code from a C++ function.
// The trampoline use the EnterJitCode signature, with the standard cdecl
// calling convention.
void JitRuntime::generateEnterJIT(JSContext* cx, MacroAssembler& masm) {
AutoCreatedBy acb(masm, "JitRuntime::generateEnterJIT");
enterJITOffset_ = startTrampolineCode(masm);
masm.assertStackAlignment(ABIStackAlignment,
-int32_t(sizeof(uintptr_t)) /* return address */);
// Save old stack frame pointer, set new stack frame pointer.
masm.push(ebp);
masm.movl(esp, ebp);
// Save non-volatile registers. These must be saved by the trampoline,
// rather than the JIT'd code, because they are scanned by the conservative
// scanner.
masm.push(ebx);
masm.push(esi);
masm.push(edi);
Register reg_argc = eax;
masm.loadPtr(Address(ebp, ARG_ARGC), reg_argc);
Register reg_argv = ebx;
masm.loadPtr(Address(ebp, ARG_ARGV), reg_argv);
Register reg_token = edx;
masm.loadPtr(Address(ebp, ARG_CALLEETOKEN), reg_token);
generateEnterJitShared(masm, reg_argc, reg_argv, reg_token, ecx, esi, edi);
// Push the descriptor.
masm.mov(Operand(ebp, ARG_RESULT), eax);
masm.unboxInt32(Address(eax, 0x0), eax);
masm.pushFrameDescriptorForJitCall(FrameType::CppToJSJit, eax, eax);
// Load the InterpreterFrame address into the OsrFrameReg.
// This address is also used for setting the constructing bit on all paths.
masm.loadPtr(Address(ebp, ARG_STACKFRAME), OsrFrameReg);
CodeLabel returnLabel;
Label oomReturnLabel;
{
// Handle Interpreter -> Baseline OSR.
AllocatableGeneralRegisterSet regs(GeneralRegisterSet::All());
MOZ_ASSERT(!regs.has(ebp));
regs.take(OsrFrameReg);
regs.take(ReturnReg);
Register scratch = regs.takeAny();
Label notOsr;
masm.branchTestPtr(Assembler::Zero, OsrFrameReg, OsrFrameReg, ¬Osr);
Register numStackValues = regs.takeAny();
masm.loadPtr(Address(ebp, ARG_STACKVALUES), numStackValues);
Register jitcode = regs.takeAny();
masm.loadPtr(Address(ebp, ARG_JITCODE), jitcode);
// Push return address.
masm.mov(&returnLabel, scratch);
masm.push(scratch);
// Frame prologue.
masm.push(ebp);
masm.mov(esp, ebp);
// Reserve frame.
masm.subPtr(Imm32(BaselineFrame::Size()), esp);
Register framePtrScratch = regs.takeAny();
masm.touchFrameValues(numStackValues, scratch, framePtrScratch);
masm.mov(esp, framePtrScratch);
// Reserve space for locals and stack values.
masm.mov(numStackValues, scratch);
masm.shll(Imm32(3), scratch);
masm.subPtr(scratch, esp);
// Enter exit frame.
masm.push(FrameDescriptor(FrameType::BaselineJS));
masm.push(Imm32(0)); // Fake return address.
masm.push(FramePointer);
// No GC things to mark on the stack, push a bare token.
masm.loadJSContext(scratch);
masm.enterFakeExitFrame(scratch, scratch, ExitFrameType::Bare);
masm.push(jitcode);
using Fn = bool (*)(BaselineFrame* frame, InterpreterFrame* interpFrame,
uint32_t numStackValues);
masm.setupUnalignedABICall(scratch);
masm.passABIArg(framePtrScratch); // BaselineFrame
masm.passABIArg(OsrFrameReg); // InterpreterFrame
masm.passABIArg(numStackValues);
masm.callWithABI<Fn, jit::InitBaselineFrameForOsr>(
ABIType::General, CheckUnsafeCallWithABI::DontCheckHasExitFrame);
masm.pop(jitcode);
MOZ_ASSERT(jitcode != ReturnReg);
Label error;
masm.addPtr(Imm32(ExitFrameLayout::SizeWithFooter()), esp);
masm.branchIfFalseBool(ReturnReg, &error);
// If OSR-ing, then emit instrumentation for setting lastProfilerFrame
// if profiler instrumentation is enabled.
{
Label skipProfilingInstrumentation;
AbsoluteAddress addressOfEnabled(
cx->runtime()->geckoProfiler().addressOfEnabled());
masm.branch32(Assembler::Equal, addressOfEnabled, Imm32(0),
&skipProfilingInstrumentation);
masm.profilerEnterFrame(ebp, scratch);
masm.bind(&skipProfilingInstrumentation);
}
masm.jump(jitcode);
// OOM: frame epilogue, load error value, discard return address and return.
masm.bind(&error);
masm.mov(ebp, esp);
masm.pop(ebp);
masm.addPtr(Imm32(sizeof(uintptr_t)), esp); // Return address.
masm.moveValue(MagicValue(JS_ION_ERROR), JSReturnOperand);
masm.jump(&oomReturnLabel);
masm.bind(¬Osr);
masm.loadPtr(Address(ebp, ARG_SCOPECHAIN), R1.scratchReg());
}
// The call will push the return address and frame pointer on the stack, thus
// we check that the stack would be aligned once the call is complete.
masm.assertStackAlignment(JitStackAlignment, 2 * sizeof(uintptr_t));
/***************************************************************
Call passed-in code, get return value and fill in the
passed in return value pointer
***************************************************************/
masm.call(Address(ebp, ARG_JITCODE));
{
// Interpreter -> Baseline OSR will return here.
masm.bind(&returnLabel);
masm.addCodeLabel(returnLabel);
masm.bind(&oomReturnLabel);
}
// Restore the stack pointer so the stack looks like this:
// +20 ... arguments ...
// +16 <return>
// +12 ebp <- %ebp pointing here.
// +8 ebx
// +4 esi
// +0 edi <- %esp pointing here.
masm.lea(Operand(ebp, -int32_t(3 * sizeof(void*))), esp);
// Store the return value.
masm.loadPtr(Address(ebp, ARG_RESULT), eax);
masm.storeValue(JSReturnOperand, Operand(eax, 0));
/**************************************************************
Return stack and registers to correct state
**************************************************************/
// Restore non-volatile registers
masm.pop(edi);
masm.pop(esi);
masm.pop(ebx);
// Restore old stack frame pointer
masm.pop(ebp);
masm.ret();
}
// static
mozilla::Maybe<::JS::ProfilingFrameIterator::RegisterState>
JitRuntime::getCppEntryRegisters(JitFrameLayout* frameStackAddress) {
// Not supported, or not implemented yet.
// TODO: Implement along with the corresponding stack-walker changes, in
return mozilla::Nothing{};
}
// Push AllRegs in a way that is compatible with RegisterDump, regardless of
// what PushRegsInMask might do to reduce the set size.
static void DumpAllRegs(MacroAssembler& masm) {
#ifdef ENABLE_WASM_SIMD
masm.PushRegsInMask(AllRegs);
#else
// When SIMD isn't supported, PushRegsInMask reduces the set of float
// registers to be double-sized, while the RegisterDump expects each of
// the float registers to have the maximal possible size
// (Simd128DataSize). To work around this, we just spill the double
// registers by hand here, using the register dump offset directly.
for (GeneralRegisterBackwardIterator iter(AllRegs.gprs()); iter.more();
++iter) {
masm.Push(*iter);
}
masm.reserveStack(sizeof(RegisterDump::FPUArray));
for (FloatRegisterBackwardIterator iter(AllRegs.fpus()); iter.more();
++iter) {
FloatRegister reg = *iter;
Address spillAddress(StackPointer, reg.getRegisterDumpOffsetInBytes());
masm.storeDouble(reg, spillAddress);
}
#endif
}
void JitRuntime::generateInvalidator(MacroAssembler& masm, Label* bailoutTail) {
AutoCreatedBy acb(masm, "JitRuntime::generateInvalidator");
invalidatorOffset_ = startTrampolineCode(masm);
// We do the minimum amount of work in assembly and shunt the rest
// off to InvalidationBailout. Assembly does:
//
// - Push the machine state onto the stack.
// - Call the InvalidationBailout routine with the stack pointer.
// - Now that the frame has been bailed out, convert the invalidated
// frame into an exit frame.
// - Do the normal check-return-code-and-thunk-to-the-interpreter dance.
// Push registers such that we can access them from [base + code].
DumpAllRegs(masm);
masm.movl(esp, eax); // Argument to jit::InvalidationBailout.
// Make space for InvalidationBailout's bailoutInfo outparam.
masm.reserveStack(sizeof(void*));
masm.movl(esp, ebx);
using Fn = bool (*)(InvalidationBailoutStack* sp, BaselineBailoutInfo** info);
masm.setupUnalignedABICall(edx);
masm.passABIArg(eax);
masm.passABIArg(ebx);
masm.callWithABI<Fn, InvalidationBailout>(
ABIType::General, CheckUnsafeCallWithABI::DontCheckOther);
masm.pop(ecx); // Get bailoutInfo outparam.
// Pop the machine state and the dead frame.
masm.moveToStackPtr(FramePointer);
// Jump to shared bailout tail. The BailoutInfo pointer has to be in ecx.
masm.jmp(bailoutTail);
}
static void PushBailoutFrame(MacroAssembler& masm, Register spArg) {
// Push registers such that we can access them from [base + code].
DumpAllRegs(masm);
// The current stack pointer is the first argument to jit::Bailout.
masm.movl(esp, spArg);
}
static void GenerateBailoutThunk(MacroAssembler& masm, Label* bailoutTail) {
PushBailoutFrame(masm, eax);
// Make space for Bailout's bailoutInfo outparam.
masm.reserveStack(sizeof(void*));
masm.movl(esp, ebx);
// Call the bailout function.
using Fn = bool (*)(BailoutStack* sp, BaselineBailoutInfo** info);
masm.setupUnalignedABICall(ecx);
masm.passABIArg(eax);
masm.passABIArg(ebx);
masm.callWithABI<Fn, Bailout>(ABIType::General,
CheckUnsafeCallWithABI::DontCheckOther);
masm.pop(ecx); // Get the bailoutInfo outparam.
// Remove both the bailout frame and the topmost Ion frame's stack.
masm.moveToStackPtr(FramePointer);
// Jump to shared bailout tail. The BailoutInfo pointer has to be in ecx.
masm.jmp(bailoutTail);
}
void JitRuntime::generateBailoutHandler(MacroAssembler& masm,
Label* bailoutTail) {
AutoCreatedBy acb(masm, "JitRuntime::generateBailoutHandler");
bailoutHandlerOffset_ = startTrampolineCode(masm);
GenerateBailoutThunk(masm, bailoutTail);
}
bool JitRuntime::generateVMWrapper(JSContext* cx, MacroAssembler& masm,
VMFunctionId id, const VMFunctionData& f,
DynFn nativeFun, uint32_t* wrapperOffset) {
AutoCreatedBy acb(masm, "JitRuntime::generateVMWrapper");
*wrapperOffset = startTrampolineCode(masm);
// Avoid conflicts with argument registers while discarding the result after
// the function call.
AllocatableGeneralRegisterSet regs(Register::Codes::WrapperMask);
static_assert(
(Register::Codes::VolatileMask & ~Register::Codes::WrapperMask) == 0,
"Wrapper register set must be a superset of Volatile register set.");
// The context is the first argument.
Register cxreg = regs.takeAny();
// Stack is:
// ... frame ...
// +8 [args]
// +4 descriptor
// +0 returnAddress
//
// Push the frame pointer to finish the exit frame, then link it up.
masm.Push(FramePointer);
masm.moveStackPtrTo(FramePointer);
masm.loadJSContext(cxreg);
masm.enterExitFrame(cxreg, regs.getAny(), id);
// Reserve space for the outparameter.
masm.reserveVMFunctionOutParamSpace(f);
masm.setupUnalignedABICallDontSaveRestoreSP();
masm.passABIArg(cxreg);
size_t argDisp = ExitFrameLayout::Size();
// Copy arguments.
for (uint32_t explicitArg = 0; explicitArg < f.explicitArgs; explicitArg++) {
switch (f.argProperties(explicitArg)) {
case VMFunctionData::WordByValue:
masm.passABIArg(MoveOperand(FramePointer, argDisp), ABIType::General);
argDisp += sizeof(void*);
break;
case VMFunctionData::DoubleByValue:
// We don't pass doubles in float registers on x86, so no need
// to check for argPassedInFloatReg.
masm.passABIArg(MoveOperand(FramePointer, argDisp), ABIType::General);
argDisp += sizeof(void*);
masm.passABIArg(MoveOperand(FramePointer, argDisp), ABIType::General);
argDisp += sizeof(void*);
break;
case VMFunctionData::WordByRef:
masm.passABIArg(MoveOperand(FramePointer, argDisp,
MoveOperand::Kind::EffectiveAddress),
ABIType::General);
argDisp += sizeof(void*);
break;
case VMFunctionData::DoubleByRef:
masm.passABIArg(MoveOperand(FramePointer, argDisp,
MoveOperand::Kind::EffectiveAddress),
ABIType::General);
argDisp += 2 * sizeof(void*);
break;
}
}
// Copy the implicit outparam, if any.
const int32_t outParamOffset =
-int32_t(ExitFooterFrame::Size()) - f.sizeOfOutParamStackSlot();
if (f.outParam != Type_Void) {
masm.passABIArg(MoveOperand(FramePointer, outParamOffset,
MoveOperand::Kind::EffectiveAddress),
ABIType::General);
}
masm.callWithABI(nativeFun, ABIType::General,
CheckUnsafeCallWithABI::DontCheckHasExitFrame);
// Test for failure.
switch (f.failType()) {
case Type_Cell:
masm.branchTestPtr(Assembler::Zero, eax, eax, masm.failureLabel());
break;
case Type_Bool:
masm.testb(eax, eax);
masm.j(Assembler::Zero, masm.failureLabel());
break;
case Type_Void:
break;
default:
MOZ_CRASH("unknown failure kind");
}
// Load the outparam.
masm.loadVMFunctionOutParam(f, Address(FramePointer, outParamOffset));
// Until C++ code is instrumented against Spectre, prevent speculative
// execution from returning any private data.
if (f.returnsData() && JitOptions.spectreJitToCxxCalls) {
masm.speculationBarrier();
}
// Pop frame and restore frame pointer.
masm.moveToStackPtr(FramePointer);
masm.pop(FramePointer);
// Return. Subtract sizeof(void*) for the frame pointer.
masm.retn(Imm32(sizeof(ExitFrameLayout) - sizeof(void*) +
f.explicitStackSlots() * sizeof(void*) +
f.extraValuesToPop * sizeof(Value)));
return true;
}
uint32_t JitRuntime::generatePreBarrier(JSContext* cx, MacroAssembler& masm,
MIRType type) {
AutoCreatedBy acb(masm, "JitRuntime::generatePreBarrier");
uint32_t offset = startTrampolineCode(masm);
static_assert(PreBarrierReg == edx);
Register temp1 = eax;
Register temp2 = ebx;
Register temp3 = ecx;
masm.push(temp1);
masm.push(temp2);
masm.push(temp3);
Label noBarrier;
masm.emitPreBarrierFastPath(cx->runtime(), type, temp1, temp2, temp3,
&noBarrier);
// Call into C++ to mark this GC thing.
masm.pop(temp3);
masm.pop(temp2);
masm.pop(temp1);
LiveRegisterSet save;
save.set() = RegisterSet(GeneralRegisterSet(Registers::VolatileMask),
FloatRegisterSet(FloatRegisters::VolatileMask));
masm.PushRegsInMask(save);
masm.movl(ImmPtr(cx->runtime()), ecx);
masm.setupUnalignedABICall(eax);
masm.passABIArg(ecx);
masm.passABIArg(edx);
masm.callWithABI(JitPreWriteBarrier(type));
masm.PopRegsInMask(save);
masm.ret();
masm.bind(&noBarrier);
masm.pop(temp3);
masm.pop(temp2);
masm.pop(temp1);
masm.ret();
return offset;
}
void JitRuntime::generateBailoutTailStub(MacroAssembler& masm,
Label* bailoutTail) {
AutoCreatedBy acb(masm, "JitRuntime::generateBailoutTailStub");
masm.bind(bailoutTail);
masm.generateBailoutTail(edx, ecx);
}