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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/DebugOnly.h"
#include "jit/Bailouts.h"
#include "jit/BaselineFrame.h"
#include "jit/CalleeToken.h"
#include "jit/JitFrames.h"
#include "jit/JitRuntime.h"
#include "jit/JitSpewer.h"
#include "jit/mips-shared/SharedICHelpers-mips-shared.h"
#include "jit/PerfSpewer.h"
#include "jit/VMFunctions.h"
#include "vm/JitActivation.h" // js::jit::JitActivation
#include "vm/JSContext.h"
#include "vm/Realm.h"
#include "jit/MacroAssembler-inl.h"
using namespace js;
using namespace js::jit;
static_assert(sizeof(uintptr_t) == sizeof(uint32_t), "Not 64-bit clean.");
struct EnterJITRegs {
double f30;
double f28;
double f26;
double f24;
double f22;
double f20;
// non-volatile registers.
uintptr_t ra;
uintptr_t fp;
uintptr_t s7;
uintptr_t s6;
uintptr_t s5;
uintptr_t s4;
uintptr_t s3;
uintptr_t s2;
uintptr_t s1;
uintptr_t s0;
};
struct EnterJITArgs {
// First 4 argumet placeholders
void* jitcode; // <- sp points here when function is entered.
int maxArgc;
Value* maxArgv;
InterpreterFrame* fp;
// Arguments on stack
CalleeToken calleeToken;
JSObject* scopeChain;
size_t numStackValues;
Value* vp;
};
static void GenerateReturn(MacroAssembler& masm, int returnCode) {
MOZ_ASSERT(masm.framePushed() == sizeof(EnterJITRegs));
// Restore non-volatile registers
masm.as_lw(s0, StackPointer, offsetof(EnterJITRegs, s0));
masm.as_lw(s1, StackPointer, offsetof(EnterJITRegs, s1));
masm.as_lw(s2, StackPointer, offsetof(EnterJITRegs, s2));
masm.as_lw(s3, StackPointer, offsetof(EnterJITRegs, s3));
masm.as_lw(s4, StackPointer, offsetof(EnterJITRegs, s4));
masm.as_lw(s5, StackPointer, offsetof(EnterJITRegs, s5));
masm.as_lw(s6, StackPointer, offsetof(EnterJITRegs, s6));
masm.as_lw(s7, StackPointer, offsetof(EnterJITRegs, s7));
masm.as_lw(fp, StackPointer, offsetof(EnterJITRegs, fp));
masm.as_lw(ra, StackPointer, offsetof(EnterJITRegs, ra));
// Restore non-volatile floating point registers
masm.as_ldc1(f20, StackPointer, offsetof(EnterJITRegs, f20));
masm.as_ldc1(f22, StackPointer, offsetof(EnterJITRegs, f22));
masm.as_ldc1(f24, StackPointer, offsetof(EnterJITRegs, f24));
masm.as_ldc1(f26, StackPointer, offsetof(EnterJITRegs, f26));
masm.as_ldc1(f28, StackPointer, offsetof(EnterJITRegs, f28));
masm.as_ldc1(f30, StackPointer, offsetof(EnterJITRegs, f30));
masm.freeStack(sizeof(EnterJITRegs));
masm.branch(ra);
}
static void GeneratePrologue(MacroAssembler& masm) {
// 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.reserveStack(sizeof(EnterJITRegs));
masm.as_sw(s0, StackPointer, offsetof(EnterJITRegs, s0));
masm.as_sw(s1, StackPointer, offsetof(EnterJITRegs, s1));
masm.as_sw(s2, StackPointer, offsetof(EnterJITRegs, s2));
masm.as_sw(s3, StackPointer, offsetof(EnterJITRegs, s3));
masm.as_sw(s4, StackPointer, offsetof(EnterJITRegs, s4));
masm.as_sw(s5, StackPointer, offsetof(EnterJITRegs, s5));
masm.as_sw(s6, StackPointer, offsetof(EnterJITRegs, s6));
masm.as_sw(s7, StackPointer, offsetof(EnterJITRegs, s7));
masm.as_sw(fp, StackPointer, offsetof(EnterJITRegs, fp));
masm.as_sw(ra, StackPointer, offsetof(EnterJITRegs, ra));
masm.as_sdc1(f20, StackPointer, offsetof(EnterJITRegs, f20));
masm.as_sdc1(f22, StackPointer, offsetof(EnterJITRegs, f22));
masm.as_sdc1(f24, StackPointer, offsetof(EnterJITRegs, f24));
masm.as_sdc1(f26, StackPointer, offsetof(EnterJITRegs, f26));
masm.as_sdc1(f28, StackPointer, offsetof(EnterJITRegs, f28));
masm.as_sdc1(f30, StackPointer, offsetof(EnterJITRegs, f30));
}
/*
* This method generates a trampoline for a c++ function with the following
* signature:
* void enter(void* code, int argc, Value* argv, InterpreterFrame* fp,
* CalleeToken calleeToken, JSObject* scopeChain, Value* vp)
* ...using standard EABI calling convention
*/
void JitRuntime::generateEnterJIT(JSContext* cx, MacroAssembler& masm) {
enterJITOffset_ = startTrampolineCode(masm);
const Register reg_code = a0;
const Register reg_argc = a1;
const Register reg_argv = a2;
const mozilla::DebugOnly<Register> reg_frame = a3;
MOZ_ASSERT(OsrFrameReg == reg_frame);
GeneratePrologue(masm);
const Address slotToken(
sp, sizeof(EnterJITRegs) + offsetof(EnterJITArgs, calleeToken));
const Address slotVp(sp, sizeof(EnterJITRegs) + offsetof(EnterJITArgs, vp));
// Save stack pointer into s4
masm.movePtr(StackPointer, s4);
// Load calleeToken into s2.
masm.loadPtr(slotToken, s2);
// Save stack pointer as baseline frame.
masm.movePtr(StackPointer, FramePointer);
// Load the number of actual arguments into s3.
masm.loadPtr(slotVp, s3);
masm.unboxInt32(Address(s3, 0), s3);
/***************************************************************
Loop over argv vector, push arguments onto stack in reverse order
***************************************************************/
// if we are constructing, that also needs to include newTarget
{
Label noNewTarget;
masm.branchTest32(Assembler::Zero, s2,
Imm32(CalleeToken_FunctionConstructing), &noNewTarget);
masm.add32(Imm32(1), reg_argc);
masm.bind(&noNewTarget);
}
masm.as_sll(s0, reg_argc, 3); // s0 = argc * 8
masm.addPtr(reg_argv, s0); // s0 = argv + argc * 8
// Loop over arguments, copying them from an unknown buffer onto the Ion
// stack so they can be accessed from JIT'ed code.
Label header, footer;
// If there aren't any arguments, don't do anything
masm.ma_b(s0, reg_argv, &footer, Assembler::BelowOrEqual, ShortJump);
{
masm.bind(&header);
masm.subPtr(Imm32(2 * sizeof(uintptr_t)), s0);
masm.subPtr(Imm32(2 * sizeof(uintptr_t)), StackPointer);
ValueOperand value = ValueOperand(s6, s7);
masm.loadValue(Address(s0, 0), value);
masm.storeValue(value, Address(StackPointer, 0));
masm.ma_b(s0, reg_argv, &header, Assembler::Above, ShortJump);
}
masm.bind(&footer);
// Create the frame descriptor.
masm.subPtr(StackPointer, s4);
masm.makeFrameDescriptor(s4, FrameType::CppToJSJit, JitFrameLayout::Size());
masm.subPtr(Imm32(2 * sizeof(uintptr_t)), StackPointer);
masm.storePtr(s3,
Address(StackPointer, sizeof(uintptr_t))); // actual arguments
masm.storePtr(s2, Address(StackPointer, 0)); // callee token
masm.push(s4); // descriptor
CodeLabel returnLabel;
Label oomReturnLabel;
{
// Handle Interpreter -> Baseline OSR.
AllocatableGeneralRegisterSet regs(GeneralRegisterSet::All());
MOZ_ASSERT(!regs.has(FramePointer));
regs.take(OsrFrameReg);
regs.take(reg_code);
regs.take(ReturnReg);
const Address slotNumStackValues(
FramePointer,
sizeof(EnterJITRegs) + offsetof(EnterJITArgs, numStackValues));
const Address slotScopeChain(
FramePointer,
sizeof(EnterJITRegs) + offsetof(EnterJITArgs, scopeChain));
Label notOsr;
masm.ma_b(OsrFrameReg, OsrFrameReg, ¬Osr, Assembler::Zero, ShortJump);
Register scratch = regs.takeAny();
Register numStackValues = regs.takeAny();
masm.load32(slotNumStackValues, numStackValues);
// Push return address.
masm.subPtr(Imm32(sizeof(uintptr_t)), StackPointer);
masm.ma_li(scratch, &returnLabel);
masm.storePtr(scratch, Address(StackPointer, 0));
// Push previous frame pointer.
masm.subPtr(Imm32(sizeof(uintptr_t)), StackPointer);
masm.storePtr(FramePointer, Address(StackPointer, 0));
// Reserve frame.
Register framePtr = FramePointer;
masm.subPtr(Imm32(BaselineFrame::Size()), StackPointer);
masm.movePtr(StackPointer, framePtr);
// Reserve space for locals and stack values.
masm.ma_sll(scratch, numStackValues, Imm32(3));
masm.subPtr(scratch, StackPointer);
// Enter exit frame.
masm.addPtr(
Imm32(BaselineFrame::Size() + BaselineFrame::FramePointerOffset),
scratch);
masm.makeFrameDescriptor(scratch, FrameType::BaselineJS,
ExitFrameLayout::Size());
// Push frame descriptor and fake return address.
masm.reserveStack(2 * sizeof(uintptr_t));
masm.storePtr(
scratch, Address(StackPointer, sizeof(uintptr_t))); // Frame descriptor
masm.storePtr(zero, Address(StackPointer, 0)); // fake return address
// No GC things to mark, push a bare token.
masm.loadJSContext(scratch);
masm.enterFakeExitFrame(scratch, scratch, ExitFrameType::Bare);
masm.reserveStack(2 * sizeof(uintptr_t));
masm.storePtr(framePtr,
Address(StackPointer, sizeof(uintptr_t))); // BaselineFrame
masm.storePtr(reg_code, Address(StackPointer, 0)); // jitcode
using Fn = bool (*)(BaselineFrame* frame, InterpreterFrame* interpFrame,
uint32_t numStackValues);
masm.setupUnalignedABICall(scratch);
masm.passABIArg(FramePointer); // BaselineFrame
masm.passABIArg(OsrFrameReg); // InterpreterFrame
masm.passABIArg(numStackValues);
masm.callWithABI<Fn, jit::InitBaselineFrameForOsr>(
ABIType::General, CheckUnsafeCallWithABI::DontCheckHasExitFrame);
regs.add(OsrFrameReg);
regs.take(JSReturnOperand);
Register jitcode = regs.takeAny();
masm.loadPtr(Address(StackPointer, 0), jitcode);
masm.loadPtr(Address(StackPointer, sizeof(uintptr_t)), framePtr);
masm.freeStack(2 * sizeof(uintptr_t));
Label error;
masm.freeStack(ExitFrameLayout::SizeWithFooter());
masm.addPtr(Imm32(BaselineFrame::Size()), framePtr);
masm.branchIfFalseBool(ReturnReg, &error);
// If OSR-ing, then emit instrumentation for setting lastProfilerFrame
// if profiler instrumentation is enabled.
{
Label skipProfilingInstrumentation;
Register realFramePtr = numStackValues;
AbsoluteAddress addressOfEnabled(
cx->runtime()->geckoProfiler().addressOfEnabled());
masm.branch32(Assembler::Equal, addressOfEnabled, Imm32(0),
&skipProfilingInstrumentation);
masm.ma_addu(realFramePtr, framePtr, Imm32(sizeof(void*)));
masm.profilerEnterFrame(realFramePtr, scratch);
masm.bind(&skipProfilingInstrumentation);
}
masm.jump(jitcode);
// OOM: load error value, discard return address and previous frame
// pointer and return.
masm.bind(&error);
masm.movePtr(framePtr, StackPointer);
masm.addPtr(Imm32(2 * sizeof(uintptr_t)), StackPointer);
masm.moveValue(MagicValue(JS_ION_ERROR), JSReturnOperand);
masm.jump(&oomReturnLabel);
masm.bind(¬Osr);
// Load the scope chain in R1.
MOZ_ASSERT(R1.scratchReg() != reg_code);
masm.loadPtr(slotScopeChain, R1.scratchReg());
}
// The call will push the return address on the stack, thus we check that
// the stack would be aligned once the call is complete.
masm.assertStackAlignment(JitStackAlignment, sizeof(uintptr_t));
// Call the function with pushing return address to stack.
masm.callJitNoProfiler(reg_code);
{
// Interpreter -> Baseline OSR will return here.
masm.bind(&returnLabel);
masm.addCodeLabel(returnLabel);
masm.bind(&oomReturnLabel);
}
// s0 <- 8*argc (size of all arguments we pushed on the stack)
masm.pop(s0);
masm.rshiftPtr(Imm32(FRAMESIZE_SHIFT), s0);
// Discard calleeToken, numActualArgs.
masm.addPtr(Imm32(2 * sizeof(uintptr_t)), StackPointer);
// Pop arguments off the stack.
masm.addPtr(s0, StackPointer);
// Store the returned value into the slotVp
masm.loadPtr(slotVp, s1);
masm.storeValue(JSReturnOperand, Address(s1, 0));
// Restore non-volatile registers and return.
GenerateReturn(masm, ShortJump);
}
// 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{};
}
void JitRuntime::generateInvalidator(MacroAssembler& masm, Label* bailoutTail) {
invalidatorOffset_ = startTrampolineCode(masm);
// NOTE: Members ionScript_ and osiPointReturnAddress_ of
// InvalidationBailoutStack are already on the stack.
static const uint32_t STACK_DATA_SIZE =
sizeof(InvalidationBailoutStack) - 2 * sizeof(uintptr_t);
// Stack has to be alligned here. If not, we will have to fix it.
masm.checkStackAlignment();
// Make room for data on stack.
masm.subPtr(Imm32(STACK_DATA_SIZE), StackPointer);
// Save general purpose registers
for (uint32_t i = 0; i < Registers::Total; i++) {
Address address =
Address(StackPointer, InvalidationBailoutStack::offsetOfRegs() +
i * sizeof(uintptr_t));
masm.storePtr(Register::FromCode(i), address);
}
// Save floating point registers
// We can use as_sd because stack is alligned.
for (uint32_t i = 0; i < FloatRegisters::TotalDouble; i++) {
masm.as_sdc1(
FloatRegister::FromIndex(i, FloatRegister::Double), StackPointer,
InvalidationBailoutStack::offsetOfFpRegs() + i * sizeof(double));
}
// Pass pointer to InvalidationBailoutStack structure.
masm.movePtr(StackPointer, a0);
// Reserve place for return value and BailoutInfo pointer
masm.subPtr(Imm32(2 * sizeof(uintptr_t)), StackPointer);
// Pass pointer to return value.
masm.ma_addu(a1, StackPointer, Imm32(sizeof(uintptr_t)));
// Pass pointer to BailoutInfo
masm.movePtr(StackPointer, a2);
using Fn = bool (*)(InvalidationBailoutStack* sp, size_t* frameSizeOut,
BaselineBailoutInfo** info);
masm.setupAlignedABICall();
masm.passABIArg(a0);
masm.passABIArg(a1);
masm.passABIArg(a2);
masm.callWithABI<Fn, InvalidationBailout>(
ABIType::General, CheckUnsafeCallWithABI::DontCheckOther);
masm.loadPtr(Address(StackPointer, 0), a2);
masm.loadPtr(Address(StackPointer, sizeof(uintptr_t)), a1);
// Remove the return address, the IonScript, the register state
// (InvaliationBailoutStack) and the space that was allocated for the
// return value.
masm.addPtr(Imm32(sizeof(InvalidationBailoutStack) + 2 * sizeof(uintptr_t)),
StackPointer);
// remove the space that this frame was using before the bailout
// (computed by InvalidationBailout)
masm.addPtr(a1, StackPointer);
// Jump to shared bailout tail. The BailoutInfo pointer has to be in r2.
masm.jump(bailoutTail);
}
void JitRuntime::generateArgumentsRectifier(MacroAssembler& masm,
ArgumentsRectifierKind kind) {
switch (kind) {
case ArgumentsRectifierKind::Normal:
argumentsRectifierOffset_ = startTrampolineCode(masm);
break;
case ArgumentsRectifierKind::TrialInlining:
trialInliningArgumentsRectifierOffset_ = startTrampolineCode(masm);
break;
}
masm.pushReturnAddress();
Register numActArgsReg = t6;
Register calleeTokenReg = t7;
Register numArgsReg = t5;
// Load the number of actual arguments into numActArgsReg
masm.loadPtr(
Address(StackPointer, RectifierFrameLayout::offsetOfNumActualArgs()),
numActArgsReg);
// Load the number of |undefined|s to push into t1.
masm.loadPtr(
Address(StackPointer, RectifierFrameLayout::offsetOfCalleeToken()),
calleeTokenReg);
// Copy the number of actual arguments into s3.
masm.mov(numActArgsReg, s3);
masm.mov(calleeTokenReg, numArgsReg);
masm.andPtr(Imm32(CalleeTokenMask), numArgsReg);
masm.loadFunctionArgCount(numArgsReg, numArgsReg);
masm.as_subu(t1, numArgsReg, s3);
// Get the topmost argument.
masm.ma_sll(t0, s3, Imm32(3)); // t0 <- nargs * 8
masm.as_addu(t2, sp, t0); // t2 <- sp + nargs * 8
masm.addPtr(Imm32(sizeof(RectifierFrameLayout)), t2);
{
Label notConstructing;
masm.branchTest32(Assembler::Zero, calleeTokenReg,
Imm32(CalleeToken_FunctionConstructing),
¬Constructing);
// Add sizeof(Value) to overcome |this|
masm.subPtr(Imm32(sizeof(Value)), StackPointer);
masm.load32(Address(t2, NUNBOX32_TYPE_OFFSET + sizeof(Value)), t0);
masm.store32(t0, Address(StackPointer, NUNBOX32_TYPE_OFFSET));
masm.load32(Address(t2, NUNBOX32_PAYLOAD_OFFSET + sizeof(Value)), t0);
masm.store32(t0, Address(StackPointer, NUNBOX32_PAYLOAD_OFFSET));
// Include the newly pushed newTarget value in the frame size
// calculated below.
masm.add32(Imm32(1), numArgsReg);
masm.bind(¬Constructing);
}
// Push undefined.
masm.moveValue(UndefinedValue(), ValueOperand(t3, t4));
{
Label undefLoopTop;
masm.bind(&undefLoopTop);
masm.subPtr(Imm32(sizeof(Value)), StackPointer);
masm.storeValue(ValueOperand(t3, t4), Address(StackPointer, 0));
masm.sub32(Imm32(1), t1);
masm.ma_b(t1, t1, &undefLoopTop, Assembler::NonZero, ShortJump);
}
// Push arguments, |nargs| + 1 times (to include |this|).
{
Label copyLoopTop, initialSkip;
masm.ma_b(&initialSkip, ShortJump);
masm.bind(©LoopTop);
masm.subPtr(Imm32(sizeof(Value)), t2);
masm.sub32(Imm32(1), s3);
masm.bind(&initialSkip);
MOZ_ASSERT(sizeof(Value) == 2 * sizeof(uint32_t));
// Read argument and push to stack.
masm.subPtr(Imm32(sizeof(Value)), StackPointer);
masm.load32(Address(t2, NUNBOX32_TYPE_OFFSET), t0);
masm.store32(t0, Address(StackPointer, NUNBOX32_TYPE_OFFSET));
masm.load32(Address(t2, NUNBOX32_PAYLOAD_OFFSET), t0);
masm.store32(t0, Address(StackPointer, NUNBOX32_PAYLOAD_OFFSET));
masm.ma_b(s3, s3, ©LoopTop, Assembler::NonZero, ShortJump);
}
// translate the framesize from values into bytes
masm.ma_addu(t0, numArgsReg, Imm32(1));
masm.lshiftPtr(Imm32(3), t0);
// Construct sizeDescriptor.
masm.makeFrameDescriptor(t0, FrameType::Rectifier, JitFrameLayout::Size());
// Construct JitFrameLayout.
masm.subPtr(Imm32(3 * sizeof(uintptr_t)), StackPointer);
// Push actual arguments.
masm.storePtr(numActArgsReg, Address(StackPointer, 2 * sizeof(uintptr_t)));
// Push callee token.
masm.storePtr(calleeTokenReg, Address(StackPointer, sizeof(uintptr_t)));
// Push frame descriptor.
masm.storePtr(t0, Address(StackPointer, 0));
// Call the target function.
masm.andPtr(Imm32(CalleeTokenMask), calleeTokenReg);
switch (kind) {
case ArgumentsRectifierKind::Normal:
masm.loadJitCodeRaw(calleeTokenReg, t1);
argumentsRectifierReturnOffset_ = masm.callJitNoProfiler(t1);
break;
case ArgumentsRectifierKind::TrialInlining:
Label noBaselineScript, done;
masm.loadBaselineJitCodeRaw(calleeTokenReg, t1, &noBaselineScript);
masm.callJitNoProfiler(t1);
masm.jump(&done);
// See BaselineCacheIRCompiler::emitCallInlinedFunction.
masm.bind(&noBaselineScript);
masm.loadJitCodeRaw(calleeTokenReg, t1);
masm.callJitNoProfiler(t1);
masm.bind(&done);
break;
}
masm.mov(FramePointer, StackPointer);
masm.pop(FramePointer);
masm.ret();
}
// NOTE: Members snapshotOffset_ and padding_ of BailoutStack
// are not stored in PushBailoutFrame().
static const uint32_t bailoutDataSize =
sizeof(BailoutStack) - 2 * sizeof(uintptr_t);
static const uint32_t bailoutInfoOutParamSize = 2 * sizeof(uintptr_t);
/* There are two different stack layouts when doing bailout. They are
* represented via class BailoutStack.
*
* - First case is when bailout is done trough bailout table. In this case
* table offset is stored in $ra (look at JitRuntime::generateBailoutTable())
* and thunk code should save it on stack. In this case frameClassId_ cannot
* be NO_FRAME_SIZE_CLASS_ID. Members snapshotOffset_ and padding_ are not on
* the stack.
*
* - Other case is when bailout is done via out of line code (lazy bailout).
* In this case frame size is stored in $ra (look at
* CodeGeneratorMIPS::generateOutOfLineCode()) and thunk code should save it
* on stack. Other difference is that members snapshotOffset_ and padding_ are
* pushed to the stack by CodeGeneratorMIPS::visitOutOfLineBailout().
*/
static void PushBailoutFrame(MacroAssembler& masm, Register spArg) {
// Make sure that alignment is proper.
masm.checkStackAlignment();
// Make room for data.
masm.subPtr(Imm32(bailoutDataSize), StackPointer);
// Save general purpose registers.
for (uint32_t i = 0; i < Registers::Total; i++) {
uint32_t off = BailoutStack::offsetOfRegs() + i * sizeof(uintptr_t);
masm.storePtr(Register::FromCode(i), Address(StackPointer, off));
}
#ifdef ENABLE_WASM_SIMD
// What to do for SIMD?
# error "Needs more careful logic if SIMD is enabled"
#endif
// Save floating point registers
// We can use as_sdc1 because stack is alligned.
for (uint32_t i = 0; i < FloatRegisters::TotalDouble; i++) {
masm.as_sdc1(FloatRegister::FromIndex(i, FloatRegister::Double),
StackPointer,
BailoutStack::offsetOfFpRegs() + i * sizeof(double));
}
// Store the frameSize_ stored in ra
// See: JitRuntime::generateBailoutTable()
// See: CodeGeneratorMIPS::generateOutOfLineCode()
masm.storePtr(ra, Address(StackPointer, BailoutStack::offsetOfFrameSize()));
#error "Code needs to be updated"
// Put pointer to BailoutStack as first argument to the Bailout()
masm.movePtr(StackPointer, spArg);
}
static void GenerateBailoutThunk(MacroAssembler& masm, Label* bailoutTail) {
PushBailoutFrame(masm, a0);
// Put pointer to BailoutInfo
masm.subPtr(Imm32(bailoutInfoOutParamSize), StackPointer);
masm.storePtr(ImmPtr(nullptr), Address(StackPointer, 0));
masm.movePtr(StackPointer, a1);
using Fn = bool (*)(BailoutStack* sp, BaselineBailoutInfo** info);
masm.setupAlignedABICall();
masm.passABIArg(a0);
masm.passABIArg(a1);
masm.callWithABI<Fn, Bailout>(ABIType::General,
CheckUnsafeCallWithABI::DontCheckOther);
// Get BailoutInfo pointer
masm.loadPtr(Address(StackPointer, 0), a2);
// Remove both the bailout frame and the topmost Ion frame's stack.
// Load frameSize from stack
masm.loadPtr(Address(StackPointer, bailoutInfoOutParamSize +
BailoutStack::offsetOfFrameSize()),
a1);
// Remove complete BailoutStack class and data after it
masm.addPtr(Imm32(sizeof(BailoutStack) + bailoutInfoOutParamSize),
StackPointer);
// Remove frame size srom stack
masm.addPtr(a1, StackPointer);
// Jump to shared bailout tail. The BailoutInfo pointer has to be in a2.
masm.jump(bailoutTail);
}
JitRuntime::BailoutTable JitRuntime::generateBailoutTable(MacroAssembler& masm,
Label* bailoutTail,
uint32_t frameClass) {
uint32_t offset = startTrampolineCode(masm);
Label bailout;
for (size_t i = 0; i < BAILOUT_TABLE_SIZE; i++) {
// Calculate offset to the end of table
int32_t offset = (BAILOUT_TABLE_SIZE - i) * BAILOUT_TABLE_ENTRY_SIZE;
// We use the 'ra' as table offset later in GenerateBailoutThunk
masm.as_bal(BOffImm16(offset));
masm.nop();
}
masm.bind(&bailout);
GenerateBailoutThunk(masm, frameClass, bailoutTail);
return BailoutTable(offset, masm.currentOffset() - offset);
}
void JitRuntime::generateBailoutHandler(MacroAssembler& masm,
Label* bailoutTail) {
bailoutHandlerOffset_ = startTrampolineCode(masm);
GenerateBailoutThunk(masm, NO_FRAME_SIZE_CLASS_ID, bailoutTail);
}
bool JitRuntime::generateVMWrapper(JSContext* cx, MacroAssembler& masm,
VMFunctionId id, const VMFunctionData& f,
DynFn nativeFun, uint32_t* wrapperOffset) {
*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 should be a superset of Volatile register set.");
// The context is the first argument; a0 is the first argument register.
Register cxreg = a0;
regs.take(cxreg);
// On link-register platforms, it is the responsibility of the VM *callee* to
// push the return address, while the caller must ensure that the address
// is stored in ra on entry. This allows the VM wrapper to work with both
// direct calls and tail calls.
masm.pushReturnAddress();
// We're aligned to an exit frame, so link it up.
masm.loadJSContext(cxreg);
masm.enterExitFrame(cxreg, regs.getAny(), id);
// Save the base of the argument set stored on the stack.
Register argsBase = InvalidReg;
if (f.explicitArgs) {
argsBase = t1; // Use temporary register.
regs.take(argsBase);
masm.ma_addu(argsBase, StackPointer,
Imm32(ExitFrameLayout::SizeWithFooter()));
}
uint32_t framePushedBeforeAlignStack = masm.framePushed();
masm.alignStackPointer();
masm.setFramePushed(0);
// Reserve space for the outparameter. Reserve sizeof(Value) for every
// case so that stack stays aligned.
uint32_t outParamSize = 0;
switch (f.outParam) {
case Type_Value:
outParamSize = sizeof(Value);
masm.reserveStack(outParamSize);
break;
case Type_Handle: {
uint32_t pushed = masm.framePushed();
masm.PushEmptyRooted(f.outParamRootType);
outParamSize = masm.framePushed() - pushed;
} break;
case Type_Bool:
case Type_Int32:
MOZ_ASSERT(sizeof(uintptr_t) == sizeof(uint32_t));
[[fallthrough]];
case Type_Pointer:
outParamSize = sizeof(uintptr_t);
masm.reserveStack(outParamSize);
break;
case Type_Double:
outParamSize = sizeof(double);
masm.reserveStack(outParamSize);
break;
default:
MOZ_ASSERT(f.outParam == Type_Void);
break;
}
uint32_t outParamOffset = 0;
if (f.outParam != Type_Void) {
// Make sure that stack is double aligned after outParam.
MOZ_ASSERT(outParamSize <= sizeof(double));
outParamOffset += sizeof(double) - outParamSize;
}
// Reserve stack for double sized args that are copied to be aligned.
outParamOffset += f.doubleByRefArgs() * sizeof(double);
Register doubleArgs = t0;
masm.reserveStack(outParamOffset);
masm.movePtr(StackPointer, doubleArgs);
masm.setupAlignedABICall();
masm.passABIArg(cxreg);
size_t argDisp = 0;
size_t doubleArgDisp = 0;
// Copy any arguments.
for (uint32_t explicitArg = 0; explicitArg < f.explicitArgs; explicitArg++) {
switch (f.argProperties(explicitArg)) {
case VMFunctionData::WordByValue:
masm.passABIArg(MoveOperand(argsBase, argDisp), ABIType::General);
argDisp += sizeof(uint32_t);
break;
case VMFunctionData::DoubleByValue:
// Values should be passed by reference, not by value, so we
// assert that the argument is a double-precision float.
MOZ_ASSERT(f.argPassedInFloatReg(explicitArg));
masm.passABIArg(MoveOperand(argsBase, argDisp), ABIType::Float64);
argDisp += sizeof(double);
break;
case VMFunctionData::WordByRef:
masm.passABIArg(
MoveOperand(argsBase, argDisp, MoveOperand::Kind::EffectiveAddress),
ABIType::General);
argDisp += sizeof(uint32_t);
break;
case VMFunctionData::DoubleByRef:
// Copy double sized argument to aligned place.
masm.ma_ldc1WordAligned(ScratchDoubleReg, argsBase, argDisp);
masm.as_sdc1(ScratchDoubleReg, doubleArgs, doubleArgDisp);
masm.passABIArg(MoveOperand(doubleArgs, doubleArgDisp,
MoveOperand::Kind::EffectiveAddress),
ABIType::General);
doubleArgDisp += sizeof(double);
argDisp += sizeof(double);
break;
}
}
MOZ_ASSERT_IF(f.outParam != Type_Void, doubleArgDisp + sizeof(double) ==
outParamOffset + outParamSize);
// Copy the implicit outparam, if any.
if (f.outParam != Type_Void) {
masm.passABIArg(MoveOperand(doubleArgs, 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, v0, v0, masm.failureLabel());
break;
case Type_Bool:
// Called functions return bools, which are 0/false and non-zero/true
masm.branchIfFalseBool(v0, masm.failureLabel());
break;
case Type_Void:
break;
default:
MOZ_CRASH("unknown failure kind");
}
masm.freeStack(outParamOffset);
// Load the outparam and free any allocated stack.
switch (f.outParam) {
case Type_Handle:
masm.popRooted(f.outParamRootType, ReturnReg, JSReturnOperand);
break;
case Type_Value:
masm.loadValue(Address(StackPointer, 0), JSReturnOperand);
masm.freeStack(sizeof(Value));
break;
case Type_Int32:
MOZ_ASSERT(sizeof(uintptr_t) == sizeof(uint32_t));
[[fallthrough]];
case Type_Pointer:
masm.load32(Address(StackPointer, 0), ReturnReg);
masm.freeStack(sizeof(uintptr_t));
break;
case Type_Bool:
masm.load8ZeroExtend(Address(StackPointer, 0), ReturnReg);
masm.freeStack(sizeof(uintptr_t));
break;
case Type_Double:
masm.as_ldc1(ReturnDoubleReg, StackPointer, 0);
masm.freeStack(sizeof(double));
break;
default:
MOZ_ASSERT(f.outParam == Type_Void);
break;
}
masm.restoreStackPointer();
masm.setFramePushed(framePushedBeforeAlignStack);
masm.leaveExitFrame();
masm.retn(Imm32(sizeof(ExitFrameLayout) +
f.explicitStackSlots() * sizeof(uintptr_t) +
f.extraValuesToPop * sizeof(Value)));
return true;
}
uint32_t JitRuntime::generatePreBarrier(JSContext* cx, MacroAssembler& masm,
MIRType type) {
uint32_t offset = startTrampolineCode(masm);
MOZ_ASSERT(PreBarrierReg == a1);
Register temp1 = a0;
Register temp2 = a2;
Register temp3 = a3;
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));
save.add(ra);
masm.PushRegsInMask(save);
masm.movePtr(ImmPtr(cx->runtime()), a0);
masm.setupUnalignedABICall(a2);
masm.passABIArg(a0);
masm.passABIArg(a1);
masm.callWithABI(JitPreWriteBarrier(type));
save.take(AnyRegister(ra));
masm.PopRegsInMask(save);
masm.ret();
masm.bind(&noBarrier);
masm.pop(temp3);
masm.pop(temp2);
masm.pop(temp1);
masm.abiret();
return offset;
}
void JitRuntime::generateExceptionTailStub(MacroAssembler& masm,
Label* profilerExitTail) {
exceptionTailOffset_ = startTrampolineCode(masm);
masm.bind(masm.failureLabel());
masm.handleFailureWithHandlerTail(profilerExitTail);
}
void JitRuntime::generateBailoutTailStub(MacroAssembler& masm,
Label* bailoutTail) {
bailoutTailOffset_ = startTrampolineCode(masm);
masm.bind(bailoutTail);
masm.generateBailoutTail(a1, a2);
}