Source code
Revision control
Copy as Markdown
Other Tools
/* -*- 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 "jit/mips32/Lowering-mips32.h"
#include "jit/Lowering.h"
#include "jit/mips32/Assembler-mips32.h"
#include "jit/MIR.h"
#include "jit/shared/Lowering-shared-inl.h"
using namespace js;
using namespace js::jit;
LBoxAllocation LIRGeneratorMIPS::useBoxFixed(MDefinition* mir, Register reg1,
Register reg2, bool useAtStart) {
MOZ_ASSERT(mir->type() == MIRType::Value);
MOZ_ASSERT(reg1 != reg2);
ensureDefined(mir);
return LBoxAllocation(LUse(reg1, mir->virtualRegister(), useAtStart),
LUse(reg2, VirtualRegisterOfPayload(mir), useAtStart));
}
void LIRGenerator::visitBox(MBox* box) {
MDefinition* inner = box->getOperand(0);
// If the box wrapped a double, it needs a new register.
if (IsFloatingPointType(inner->type())) {
defineBox(new (alloc()) LBoxFloatingPoint(
useRegisterAtStart(inner), tempCopy(inner, 0), inner->type()),
box);
return;
}
if (box->canEmitAtUses()) {
emitAtUses(box);
return;
}
if (inner->isConstant()) {
defineBox(new (alloc()) LValue(inner->toConstant()->toJSValue()), box);
return;
}
LBox* lir = new (alloc()) LBox(use(inner), inner->type());
// Otherwise, we should not define a new register for the payload portion
// of the output, so bypass defineBox().
uint32_t vreg = getVirtualRegister();
// Note that because we're using BogusTemp(), we do not change the type of
// the definition. We also do not define the first output as "TYPE",
// because it has no corresponding payload at (vreg + 1). Also note that
// although we copy the input's original type for the payload half of the
// definition, this is only for clarity. BogusTemp() definitions are
// ignored.
lir->setDef(0, LDefinition(vreg, LDefinition::GENERAL));
lir->setDef(1, LDefinition::BogusTemp());
box->setVirtualRegister(vreg);
add(lir);
}
void LIRGenerator::visitUnbox(MUnbox* unbox) {
MDefinition* inner = unbox->getOperand(0);
// An unbox on mips reads in a type tag (either in memory or a register) and
// a payload. Unlike most instructions consuming a box, we ask for the type
// second, so that the result can re-use the first input.
MOZ_ASSERT(inner->type() == MIRType::Value);
ensureDefined(inner);
if (IsFloatingPointType(unbox->type())) {
LUnboxFloatingPoint* lir =
new (alloc()) LUnboxFloatingPoint(useBox(inner), unbox->type());
if (unbox->fallible()) {
assignSnapshot(lir, unbox->bailoutKind());
}
define(lir, unbox);
return;
}
// Swap the order we use the box pieces so we can re-use the payload
// register.
LUnbox* lir = new (alloc()) LUnbox;
lir->setOperand(0, usePayloadInRegisterAtStart(inner));
lir->setOperand(1, useType(inner, LUse::REGISTER));
if (unbox->fallible()) {
assignSnapshot(lir, unbox->bailoutKind());
}
// Types and payloads form two separate intervals. If the type becomes dead
// before the payload, it could be used as a Value without the type being
// recoverable. Unbox's purpose is to eagerly kill the definition of a type
// tag, so keeping both alive (for the purpose of gcmaps) is unappealing.
// Instead, we create a new virtual register.
defineReuseInput(lir, unbox, 0);
}
void LIRGenerator::visitReturnImpl(MDefinition* opd, bool isGenerator) {
MOZ_ASSERT(opd->type() == MIRType::Value);
LReturn* ins = new (alloc()) LReturn(isGenerator);
ins->setOperand(0, LUse(JSReturnReg_Type));
ins->setOperand(1, LUse(JSReturnReg_Data));
fillBoxUses(ins, 0, opd);
add(ins);
}
void LIRGeneratorMIPS::lowerUntypedPhiInput(MPhi* phi, uint32_t inputPosition,
LBlock* block, size_t lirIndex) {
MDefinition* operand = phi->getOperand(inputPosition);
LPhi* type = block->getPhi(lirIndex + VREG_TYPE_OFFSET);
LPhi* payload = block->getPhi(lirIndex + VREG_DATA_OFFSET);
type->setOperand(
inputPosition,
LUse(operand->virtualRegister() + VREG_TYPE_OFFSET, LUse::ANY));
payload->setOperand(inputPosition,
LUse(VirtualRegisterOfPayload(operand), LUse::ANY));
}
void LIRGeneratorMIPS::defineInt64Phi(MPhi* phi, size_t lirIndex) {
LPhi* low = current->getPhi(lirIndex + INT64LOW_INDEX);
LPhi* high = current->getPhi(lirIndex + INT64HIGH_INDEX);
uint32_t lowVreg = getVirtualRegister();
phi->setVirtualRegister(lowVreg);
uint32_t highVreg = getVirtualRegister();
MOZ_ASSERT(lowVreg + INT64HIGH_INDEX == highVreg + INT64LOW_INDEX);
low->setDef(0, LDefinition(lowVreg, LDefinition::INT32));
high->setDef(0, LDefinition(highVreg, LDefinition::INT32));
annotate(high);
annotate(low);
}
void LIRGeneratorMIPS::lowerInt64PhiInput(MPhi* phi, uint32_t inputPosition,
LBlock* block, size_t lirIndex) {
MDefinition* operand = phi->getOperand(inputPosition);
LPhi* low = block->getPhi(lirIndex + INT64LOW_INDEX);
LPhi* high = block->getPhi(lirIndex + INT64HIGH_INDEX);
low->setOperand(inputPosition,
LUse(operand->virtualRegister() + INT64LOW_INDEX, LUse::ANY));
high->setOperand(
inputPosition,
LUse(operand->virtualRegister() + INT64HIGH_INDEX, LUse::ANY));
}
void LIRGeneratorMIPS::lowerTruncateDToInt32(MTruncateToInt32* ins) {
MDefinition* opd = ins->input();
MOZ_ASSERT(opd->type() == MIRType::Double);
define(new (alloc())
LTruncateDToInt32(useRegister(opd), LDefinition::BogusTemp()),
ins);
}
void LIRGeneratorMIPS::lowerTruncateFToInt32(MTruncateToInt32* ins) {
MDefinition* opd = ins->input();
MOZ_ASSERT(opd->type() == MIRType::Float32);
define(new (alloc())
LTruncateFToInt32(useRegister(opd), LDefinition::BogusTemp()),
ins);
}
void LIRGeneratorMIPS::lowerDivI64(MDiv* div) {
if (div->isUnsigned()) {
lowerUDivI64(div);
return;
}
LDivOrModI64* lir = new (alloc()) LDivOrModI64(
useInt64RegisterAtStart(div->lhs()), useInt64RegisterAtStart(div->rhs()));
defineReturn(lir, div);
}
void LIRGeneratorMIPS::lowerWasmBuiltinDivI64(MWasmBuiltinDivI64* div) {
MOZ_CRASH("We don't use runtime div for this architecture");
}
void LIRGeneratorMIPS::lowerModI64(MMod* mod) {
if (mod->isUnsigned()) {
lowerUModI64(mod);
return;
}
LDivOrModI64* lir = new (alloc()) LDivOrModI64(
useInt64RegisterAtStart(mod->lhs()), useInt64RegisterAtStart(mod->rhs()));
defineReturn(lir, mod);
}
void LIRGeneratorMIPS::lowerWasmBuiltinModI64(MWasmBuiltinModI64* mod) {
MOZ_CRASH("We don't use runtime mod for this architecture");
}
void LIRGeneratorMIPS::lowerUDivI64(MDiv* div) {
LUDivOrModI64* lir = new (alloc()) LUDivOrModI64(
useInt64RegisterAtStart(div->lhs()), useInt64RegisterAtStart(div->rhs()));
defineReturn(lir, div);
}
void LIRGeneratorMIPS::lowerUModI64(MMod* mod) {
LUDivOrModI64* lir = new (alloc()) LUDivOrModI64(
useInt64RegisterAtStart(mod->lhs()), useInt64RegisterAtStart(mod->rhs()));
defineReturn(lir, mod);
}
void LIRGeneratorMIPS::lowerBigIntDiv(MBigIntDiv* ins) {
auto* lir = new (alloc()) LBigIntDiv(useRegister(ins->lhs()),
useRegister(ins->rhs()), temp(), temp());
define(lir, ins);
assignSafepoint(lir, ins);
}
void LIRGeneratorMIPS::lowerBigIntMod(MBigIntMod* ins) {
auto* lir = new (alloc()) LBigIntMod(useRegister(ins->lhs()),
useRegister(ins->rhs()), temp(), temp());
define(lir, ins);
assignSafepoint(lir, ins);
}
void LIRGenerator::visitWasmTruncateToInt64(MWasmTruncateToInt64* ins) {
MDefinition* opd = ins->input();
MOZ_ASSERT(opd->type() == MIRType::Double || opd->type() == MIRType::Float32);
defineReturn(new (alloc()) LWasmTruncateToInt64(useRegisterAtStart(opd)),
ins);
}
void LIRGeneratorMIPS::lowerWasmBuiltinTruncateToInt64(
MWasmBuiltinTruncateToInt64* ins) {
MOZ_CRASH("We don't use it for this architecture");
}
void LIRGenerator::visitInt64ToFloatingPoint(MInt64ToFloatingPoint* ins) {
MDefinition* opd = ins->input();
MOZ_ASSERT(opd->type() == MIRType::Int64);
MOZ_ASSERT(IsFloatingPointType(ins->type()));
defineReturn(
new (alloc()) LInt64ToFloatingPoint(useInt64RegisterAtStart(opd)), ins);
}
void LIRGeneratorMIPS::lowerBuiltinInt64ToFloatingPoint(
MBuiltinInt64ToFloatingPoint* ins) {
MOZ_CRASH("We don't use it for this architecture");
}