Mypal/js/src/jit/mips32/Lowering-mips32.cpp
2019-03-11 13:26:37 +03:00

259 lines
8.4 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=8 sts=4 et sw=4 tw=99:
* 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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "jit/mips32/Lowering-mips32.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
LIRGeneratorMIPS::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
LIRGeneratorMIPS::visitUnbox(MUnbox* unbox)
{
MDefinition* inner = unbox->getOperand(0);
if (inner->type() == MIRType::ObjectOrNull) {
LUnboxObjectOrNull* lir = new(alloc()) LUnboxObjectOrNull(useRegisterAtStart(inner));
if (unbox->fallible())
assignSnapshot(lir, unbox->bailoutKind());
defineReuseInput(lir, unbox, 0);
return;
}
// 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
LIRGeneratorMIPS::visitReturn(MReturn* ret)
{
MDefinition* opd = ret->getOperand(0);
MOZ_ASSERT(opd->type() == MIRType::Value);
LReturn* ins = new(alloc()) LReturn;
ins->setOperand(0, LUse(JSReturnReg_Type));
ins->setOperand(1, LUse(JSReturnReg_Data));
fillBoxUses(ins, 0, opd);
add(ins);
}
void
LIRGeneratorMIPS::defineUntypedPhi(MPhi* phi, size_t lirIndex)
{
LPhi* type = current->getPhi(lirIndex + VREG_TYPE_OFFSET);
LPhi* payload = current->getPhi(lirIndex + VREG_DATA_OFFSET);
uint32_t typeVreg = getVirtualRegister();
phi->setVirtualRegister(typeVreg);
uint32_t payloadVreg = getVirtualRegister();
MOZ_ASSERT(typeVreg + 1 == payloadVreg);
type->setDef(0, LDefinition(typeVreg, LDefinition::TYPE));
payload->setDef(0, LDefinition(payloadVreg, LDefinition::PAYLOAD));
annotate(type);
annotate(payload);
}
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::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::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::visitRandom(MRandom* ins)
{
LRandom *lir = new(alloc()) LRandom(temp(),
temp(),
temp(),
temp(),
temp());
defineFixed(lir, ins, LFloatReg(ReturnDoubleReg));
}