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swiftshader / SwiftShader / 1fd80c722c1a2d4c31d43a0df35ccbd49d9c2b5a / . / src / IceTargetLoweringMIPS32.cpp
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//
// The Subzero Code Generator
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
///
/// \file
/// \brief Implements the TargetLoweringMIPS32 class, which consists almost
/// entirely of the lowering sequence for each high-level instruction.
///
//===----------------------------------------------------------------------===//
#include "IceTargetLoweringMIPS32.h"
#include "IceCfg.h"
#include "IceCfgNode.h"
#include "IceClFlags.h"
#include "IceDefs.h"
#include "IceELFObjectWriter.h"
#include "IceGlobalInits.h"
#include "IceInstMIPS32.h"
#include "IceInstVarIter.h"
#include "IceLiveness.h"
#include "IceOperand.h"
#include "IcePhiLoweringImpl.h"
#include "IceRegistersMIPS32.h"
#include "IceTargetLoweringMIPS32.def"
#include "IceUtils.h"
#include "llvm/Support/MathExtras.h"
namespace MIPS32 {
std::unique_ptr<::Ice::TargetLowering> createTargetLowering(::Ice::Cfg *Func) {
return ::Ice::MIPS32::TargetMIPS32::create(Func);
}
std::unique_ptr<::Ice::TargetDataLowering>
createTargetDataLowering(::Ice::GlobalContext *Ctx) {
return ::Ice::MIPS32::TargetDataMIPS32::create(Ctx);
}
std::unique_ptr<::Ice::TargetHeaderLowering>
createTargetHeaderLowering(::Ice::GlobalContext *Ctx) {
return ::Ice::MIPS32::TargetHeaderMIPS32::create(Ctx);
}
void staticInit(::Ice::GlobalContext *Ctx) {
::Ice::MIPS32::TargetMIPS32::staticInit(Ctx);
}
bool shouldBePooled(const ::Ice::Constant *C) {
return ::Ice::MIPS32::TargetMIPS32::shouldBePooled(C);
}
} // end of namespace MIPS32
namespace Ice {
namespace MIPS32 {
using llvm::isInt;
namespace {
// The maximum number of arguments to pass in GPR registers.
constexpr uint32_t MIPS32_MAX_GPR_ARG = 4;
std::array<RegNumT, MIPS32_MAX_GPR_ARG> GPRArgInitializer;
std::array<RegNumT, MIPS32_MAX_GPR_ARG / 2> I64ArgInitializer;
constexpr uint32_t MIPS32_MAX_FP_ARG = 2;
std::array<RegNumT, MIPS32_MAX_FP_ARG> FP32ArgInitializer;
std::array<RegNumT, MIPS32_MAX_FP_ARG> FP64ArgInitializer;
const char *getRegClassName(RegClass C) {
auto ClassNum = static_cast<RegClassMIPS32>(C);
assert(ClassNum < RCMIPS32_NUM);
switch (ClassNum) {
default:
assert(C < RC_Target);
return regClassString(C);
// Add handling of new register classes below.
}
}
// Stack alignment
constexpr uint32_t MIPS32_STACK_ALIGNMENT_BYTES = 8;
// Value is in bytes. Return Value adjusted to the next highest multiple of the
// stack alignment required for the given type.
uint32_t applyStackAlignmentTy(uint32_t Value, Type Ty) {
size_t typeAlignInBytes = typeWidthInBytes(Ty);
if (isVectorType(Ty))
UnimplementedError(getFlags());
return Utils::applyAlignment(Value, typeAlignInBytes);
}
// Value is in bytes. Return Value adjusted to the next highest multiple of the
// stack alignment.
uint32_t applyStackAlignment(uint32_t Value) {
return Utils::applyAlignment(Value, MIPS32_STACK_ALIGNMENT_BYTES);
}
} // end of anonymous namespace
TargetMIPS32::TargetMIPS32(Cfg *Func) : TargetLowering(Func) {}
void TargetMIPS32::staticInit(GlobalContext *Ctx) {
(void)Ctx;
RegNumT::setLimit(RegMIPS32::Reg_NUM);
SmallBitVector IntegerRegisters(RegMIPS32::Reg_NUM);
SmallBitVector I64PairRegisters(RegMIPS32::Reg_NUM);
SmallBitVector Float32Registers(RegMIPS32::Reg_NUM);
SmallBitVector Float64Registers(RegMIPS32::Reg_NUM);
SmallBitVector VectorRegisters(RegMIPS32::Reg_NUM);
SmallBitVector InvalidRegisters(RegMIPS32::Reg_NUM);
#define X(val, encode, name, scratch, preserved, stackptr, frameptr, isInt, \
isI64Pair, isFP32, isFP64, isVec128, alias_init) \
IntegerRegisters[RegMIPS32::val] = isInt; \
I64PairRegisters[RegMIPS32::val] = isI64Pair; \
Float32Registers[RegMIPS32::val] = isFP32; \
Float64Registers[RegMIPS32::val] = isFP64; \
VectorRegisters[RegMIPS32::val] = isVec128; \
RegisterAliases[RegMIPS32::val].resize(RegMIPS32::Reg_NUM); \
for (SizeT RegAlias : alias_init) { \
assert(!RegisterAliases[RegMIPS32::val][RegAlias] && \
"Duplicate alias for " #val); \
RegisterAliases[RegMIPS32::val].set(RegAlias); \
} \
RegisterAliases[RegMIPS32::val].resize(RegMIPS32::Reg_NUM); \
assert(RegisterAliases[RegMIPS32::val][RegMIPS32::val]);
REGMIPS32_TABLE;
#undef X
// TODO(mohit.bhakkad): Change these inits once we provide argument related
// field in register tables
for (size_t i = 0; i < MIPS32_MAX_GPR_ARG; i++)
GPRArgInitializer[i] = RegNumT::fixme(RegMIPS32::Reg_A0 + i);
for (size_t i = 0; i < MIPS32_MAX_GPR_ARG / 2; i++)
I64ArgInitializer[i] = RegNumT::fixme(RegMIPS32::Reg_A0A1 + i);
for (size_t i = 0; i < MIPS32_MAX_FP_ARG; i++) {
FP32ArgInitializer[i] = RegNumT::fixme(RegMIPS32::Reg_F12 + i * 2);
FP64ArgInitializer[i] = RegNumT::fixme(RegMIPS32::Reg_F12F13 + i);
}
TypeToRegisterSet[IceType_void] = InvalidRegisters;
TypeToRegisterSet[IceType_i1] = IntegerRegisters;
TypeToRegisterSet[IceType_i8] = IntegerRegisters;
TypeToRegisterSet[IceType_i16] = IntegerRegisters;
TypeToRegisterSet[IceType_i32] = IntegerRegisters;
TypeToRegisterSet[IceType_i64] = IntegerRegisters;
TypeToRegisterSet[IceType_f32] = Float32Registers;
TypeToRegisterSet[IceType_f64] = Float64Registers;
TypeToRegisterSet[IceType_v4i1] = VectorRegisters;
TypeToRegisterSet[IceType_v8i1] = VectorRegisters;
TypeToRegisterSet[IceType_v16i1] = VectorRegisters;
TypeToRegisterSet[IceType_v16i8] = VectorRegisters;
TypeToRegisterSet[IceType_v8i16] = VectorRegisters;
TypeToRegisterSet[IceType_v4i32] = VectorRegisters;
TypeToRegisterSet[IceType_v4f32] = VectorRegisters;
for (size_t i = 0; i < llvm::array_lengthof(TypeToRegisterSet); ++i)
TypeToRegisterSetUnfiltered[i] = TypeToRegisterSet[i];
filterTypeToRegisterSet(Ctx, RegMIPS32::Reg_NUM, TypeToRegisterSet,
llvm::array_lengthof(TypeToRegisterSet),
RegMIPS32::getRegName, getRegClassName);
}
void TargetMIPS32::unsetIfNonLeafFunc() {
for (CfgNode *Node : Func->getNodes()) {
for (Inst &Instr : Node->getInsts()) {
if (llvm::isa<InstCall>(&Instr)) {
// Unset MaybeLeafFunc if call instruction exists.
MaybeLeafFunc = false;
return;
}
}
}
}
uint32_t TargetMIPS32::getStackAlignment() const {
return MIPS32_STACK_ALIGNMENT_BYTES;
}
void TargetMIPS32::findMaxStackOutArgsSize() {
// MinNeededOutArgsBytes should be updated if the Target ever creates a
// high-level InstCall that requires more stack bytes.
size_t MinNeededOutArgsBytes = 0;
if (!MaybeLeafFunc)
MinNeededOutArgsBytes = MIPS32_MAX_GPR_ARG * 4;
MaxOutArgsSizeBytes = MinNeededOutArgsBytes;
for (CfgNode *Node : Func->getNodes()) {
Context.init(Node);
while (!Context.atEnd()) {
PostIncrLoweringContext PostIncrement(Context);
Inst *CurInstr = iteratorToInst(Context.getCur());
if (auto *Call = llvm::dyn_cast<InstCall>(CurInstr)) {
SizeT OutArgsSizeBytes = getCallStackArgumentsSizeBytes(Call);
MaxOutArgsSizeBytes = std::max(MaxOutArgsSizeBytes, OutArgsSizeBytes);
}
}
}
}
void TargetMIPS32::translateO2() {
TimerMarker T(TimerStack::TT_O2, Func);
// TODO(stichnot): share passes with X86?
// https://code.google.com/p/nativeclient/issues/detail?id=4094
genTargetHelperCalls();
unsetIfNonLeafFunc();
findMaxStackOutArgsSize();
// Merge Alloca instructions, and lay out the stack.
static constexpr bool SortAndCombineAllocas = true;
Func->processAllocas(SortAndCombineAllocas);
Func->dump("After Alloca processing");
if (!getFlags().getEnablePhiEdgeSplit()) {
// Lower Phi instructions.
Func->placePhiLoads();
if (Func->hasError())
return;
Func->placePhiStores();
if (Func->hasError())
return;
Func->deletePhis();
if (Func->hasError())
return;
Func->dump("After Phi lowering");
}
// Address mode optimization.
Func->getVMetadata()->init(VMK_SingleDefs);
Func->doAddressOpt();
// Argument lowering
Func->doArgLowering();
// Target lowering. This requires liveness analysis for some parts of the
// lowering decisions, such as compare/branch fusing. If non-lightweight
// liveness analysis is used, the instructions need to be renumbered first.
// TODO: This renumbering should only be necessary if we're actually
// calculating live intervals, which we only do for register allocation.
Func->renumberInstructions();
if (Func->hasError())
return;
// TODO: It should be sufficient to use the fastest liveness calculation,
// i.e. livenessLightweight(). However, for some reason that slows down the
// rest of the translation. Investigate.
Func->liveness(Liveness_Basic);
if (Func->hasError())
return;
Func->dump("After MIPS32 address mode opt");
Func->genCode();
if (Func->hasError())
return;
Func->dump("After MIPS32 codegen");
// Register allocation. This requires instruction renumbering and full
// liveness analysis.
Func->renumberInstructions();
if (Func->hasError())
return;
Func->liveness(Liveness_Intervals);
if (Func->hasError())
return;
// The post-codegen dump is done here, after liveness analysis and associated
// cleanup, to make the dump cleaner and more useful.
Func->dump("After initial MIPS32 codegen");
// Validate the live range computations. The expensive validation call is
// deliberately only made when assertions are enabled.
assert(Func->validateLiveness());
Func->getVMetadata()->init(VMK_All);
regAlloc(RAK_Global);
if (Func->hasError())
return;
Func->dump("After linear scan regalloc");
if (getFlags().getEnablePhiEdgeSplit()) {
Func->advancedPhiLowering();
Func->dump("After advanced Phi lowering");
}
// Stack frame mapping.
Func->genFrame();
if (Func->hasError())
return;
Func->dump("After stack frame mapping");
Func->contractEmptyNodes();
Func->reorderNodes();
// Branch optimization. This needs to be done just before code emission. In
// particular, no transformations that insert or reorder CfgNodes should be
// done after branch optimization. We go ahead and do it before nop insertion
// to reduce the amount of work needed for searching for opportunities.
Func->doBranchOpt();
Func->dump("After branch optimization");
// Nop insertion
if (getFlags().getShouldDoNopInsertion()) {
Func->doNopInsertion();
}
}
void TargetMIPS32::translateOm1() {
TimerMarker T(TimerStack::TT_Om1, Func);
// TODO: share passes with X86?
genTargetHelperCalls();
unsetIfNonLeafFunc();
findMaxStackOutArgsSize();
// Do not merge Alloca instructions, and lay out the stack.
static constexpr bool SortAndCombineAllocas = false;
Func->processAllocas(SortAndCombineAllocas);
Func->dump("After Alloca processing");
Func->placePhiLoads();
if (Func->hasError())
return;
Func->placePhiStores();
if (Func->hasError())
return;
Func->deletePhis();
if (Func->hasError())
return;
Func->dump("After Phi lowering");
Func->doArgLowering();
Func->genCode();
if (Func->hasError())
return;
Func->dump("After initial MIPS32 codegen");
regAlloc(RAK_InfOnly);
if (Func->hasError())
return;
Func->dump("After regalloc of infinite-weight variables");
Func->genFrame();
if (Func->hasError())
return;
Func->dump("After stack frame mapping");
// Nop insertion
if (getFlags().getShouldDoNopInsertion()) {
Func->doNopInsertion();
}
}
bool TargetMIPS32::doBranchOpt(Inst *Instr, const CfgNode *NextNode) {
(void)Instr;
(void)NextNode;
UnimplementedError(getFlags());
return false;
}
namespace {
const char *RegNames[RegMIPS32::Reg_NUM] = {
#define X(val, encode, name, scratch, preserved, stackptr, frameptr, isInt, \
isI64Pair, isFP32, isFP64, isVec128, alias_init) \
name,
REGMIPS32_TABLE
#undef X
};
} // end of anonymous namespace
const char *RegMIPS32::getRegName(RegNumT RegNum) {
RegNum.assertIsValid();
return RegNames[RegNum];
}
const char *TargetMIPS32::getRegName(RegNumT RegNum, Type Ty) const {
(void)Ty;
return RegMIPS32::getRegName(RegNum);
}
Variable *TargetMIPS32::getPhysicalRegister(RegNumT RegNum, Type Ty) {
if (Ty == IceType_void)
Ty = IceType_i32;
if (PhysicalRegisters[Ty].empty())
PhysicalRegisters[Ty].resize(RegMIPS32::Reg_NUM);
RegNum.assertIsValid();
Variable *Reg = PhysicalRegisters[Ty][RegNum];
if (Reg == nullptr) {
Reg = Func->makeVariable(Ty);
Reg->setRegNum(RegNum);
PhysicalRegisters[Ty][RegNum] = Reg;
// Specially mark a named physical register as an "argument" so that it is
// considered live upon function entry. Otherwise it's possible to get
// liveness validation errors for saving callee-save registers.
Func->addImplicitArg(Reg);
// Don't bother tracking the live range of a named physical register.
Reg->setIgnoreLiveness();
}
return Reg;
}
void TargetMIPS32::emitJumpTable(const Cfg *Func,
const InstJumpTable *JumpTable) const {
(void)Func;
(void)JumpTable;
UnimplementedError(getFlags());
}
/// Provide a trivial wrapper to legalize() for this common usage.
Variable *TargetMIPS32::legalizeToReg(Operand *From, RegNumT RegNum) {
return llvm::cast<Variable>(legalize(From, Legal_Reg, RegNum));
}
/// Legalize undef values to concrete values.
Operand *TargetMIPS32::legalizeUndef(Operand *From, RegNumT RegNum) {
(void)RegNum;
Type Ty = From->getType();
if (llvm::isa<ConstantUndef>(From)) {
// Lower undefs to zero. Another option is to lower undefs to an
// uninitialized register; however, using an uninitialized register
// results in less predictable code.
//
// If in the future the implementation is changed to lower undef
// values to uninitialized registers, a FakeDef will be needed:
// Context.insert(InstFakeDef::create(Func, Reg));
// This is in order to ensure that the live range of Reg is not
// overestimated. If the constant being lowered is a 64 bit value,
// then the result should be split and the lo and hi components will
// need to go in uninitialized registers.
if (isVectorType(Ty))
UnimplementedError(getFlags());
return Ctx->getConstantZero(Ty);
}
return From;
}
Variable *TargetMIPS32::makeReg(Type Type, RegNumT RegNum) {
// There aren't any 64-bit integer registers for Mips32.
assert(Type != IceType_i64);
Variable *Reg = Func->makeVariable(Type);
if (RegNum.hasValue())
Reg->setRegNum(RegNum);
else
Reg->setMustHaveReg();
return Reg;
}
OperandMIPS32Mem *TargetMIPS32::formMemoryOperand(Operand *Operand, Type Ty) {
// It may be the case that address mode optimization already creates an
// OperandMIPS32Mem, so in that case it wouldn't need another level of
// transformation.
if (auto *Mem = llvm::dyn_cast<OperandMIPS32Mem>(Operand)) {
return Mem;
}
// If we didn't do address mode optimization, then we only have a base/offset
// to work with. MIPS always requires a base register, so just use that to
// hold the operand.
auto *Base = llvm::cast<Variable>(legalize(Operand, Legal_Reg));
return OperandMIPS32Mem::create(
Func, Ty, Base, llvm::cast<ConstantInteger32>(
Ctx->getConstantInt32(Base->getStackOffset())));
}
void TargetMIPS32::emitVariable(const Variable *Var) const {
if (!BuildDefs::dump())
return;
Ostream &Str = Ctx->getStrEmit();
const Type FrameSPTy = IceType_i32;
if (Var->hasReg()) {
Str << '$' << getRegName(Var->getRegNum(), Var->getType());
} else {
int32_t Offset = Var->getStackOffset();
Str << Offset;
Str << "($" << getRegName(getFrameOrStackReg(), FrameSPTy);
Str << ")";
}
}
TargetMIPS32::CallingConv::CallingConv()
: GPRegsUsed(RegMIPS32::Reg_NUM),
GPRArgs(GPRArgInitializer.rbegin(), GPRArgInitializer.rend()),
I64Args(I64ArgInitializer.rbegin(), I64ArgInitializer.rend()),
VFPRegsUsed(RegMIPS32::Reg_NUM),
FP32Args(FP32ArgInitializer.rbegin(), FP32ArgInitializer.rend()),
FP64Args(FP64ArgInitializer.rbegin(), FP64ArgInitializer.rend()) {}
// In MIPS O32 abi FP argument registers can be used only if first argument is
// of type float/double. UseFPRegs flag is used to care of that. Also FP arg
// registers can be used only for first 2 arguments, so we require argument
// number to make register allocation decisions.
bool TargetMIPS32::CallingConv::argInReg(Type Ty, uint32_t ArgNo,
RegNumT *Reg) {
if (isScalarIntegerType(Ty))
return argInGPR(Ty, Reg);
if (isScalarFloatingType(Ty)) {
if (ArgNo == 0) {
UseFPRegs = true;
return argInVFP(Ty, Reg);
}
if (UseFPRegs && ArgNo == 1) {
UseFPRegs = false;
return argInVFP(Ty, Reg);
}
return argInGPR(Ty, Reg);
}
UnimplementedError(getFlags());
return false;
}
bool TargetMIPS32::CallingConv::argInGPR(Type Ty, RegNumT *Reg) {
CfgVector<RegNumT> *Source;
switch (Ty) {
default: {
UnimplementedError(getFlags());
return false;
} break;
case IceType_i32:
case IceType_f32: {
Source = &GPRArgs;
} break;
case IceType_i64:
case IceType_f64: {
Source = &I64Args;
} break;
}
discardUnavailableGPRsAndTheirAliases(Source);
if (Source->empty()) {
GPRegsUsed.set();
return false;
}
*Reg = Source->back();
// Note that we don't Source->pop_back() here. This is intentional. Notice how
// we mark all of Reg's aliases as Used. So, for the next argument,
// Source->back() is marked as unavailable, and it is thus implicitly popped
// from the stack.
GPRegsUsed |= RegisterAliases[*Reg];
return true;
}
inline void TargetMIPS32::CallingConv::discardNextGPRAndItsAliases(
CfgVector<RegNumT> *Regs) {
GPRegsUsed |= RegisterAliases[Regs->back()];
Regs->pop_back();
}
// GPR are not packed when passing parameters. Thus, a function foo(i32, i64,
// i32) will have the first argument in a0, the second in a2-a3, and the third
// on the stack. To model this behavior, whenever we pop a register from Regs,
// we remove all of its aliases from the pool of available GPRs. This has the
// effect of computing the "closure" on the GPR registers.
void TargetMIPS32::CallingConv::discardUnavailableGPRsAndTheirAliases(
CfgVector<RegNumT> *Regs) {
while (!Regs->empty() && GPRegsUsed[Regs->back()]) {
discardNextGPRAndItsAliases(Regs);
}
}
bool TargetMIPS32::CallingConv::argInVFP(Type Ty, RegNumT *Reg) {
CfgVector<RegNumT> *Source;
switch (Ty) {
default: {
UnimplementedError(getFlags());
return false;
} break;
case IceType_f32: {
Source = &FP32Args;
} break;
case IceType_f64: {
Source = &FP64Args;
} break;
}
discardUnavailableVFPRegsAndTheirAliases(Source);
if (Source->empty()) {
VFPRegsUsed.set();
return false;
}
*Reg = Source->back();
VFPRegsUsed |= RegisterAliases[*Reg];
// In MIPS O32 abi if fun arguments are (f32, i32) then one can not use reg_a0
// for second argument even though it's free. f32 arg goes in reg_f12, i32 arg
// goes in reg_a1. Similarly if arguments are (f64, i32) second argument goes
// in reg_a3 and a0, a1 are not used.
Source = &GPRArgs;
// Discard one GPR reg for f32(4 bytes), two for f64(4 + 4 bytes)
discardNextGPRAndItsAliases(Source);
if (Ty == IceType_f64)
discardNextGPRAndItsAliases(Source);
return true;
}
void TargetMIPS32::CallingConv::discardUnavailableVFPRegsAndTheirAliases(
CfgVector<RegNumT> *Regs) {
while (!Regs->empty() && VFPRegsUsed[Regs->back()]) {
Regs->pop_back();
}
}
void TargetMIPS32::lowerArguments() {
VarList &Args = Func->getArgs();
TargetMIPS32::CallingConv CC;
// For each register argument, replace Arg in the argument list with the home
// register. Then generate an instruction in the prolog to copy the home
// register to the assigned location of Arg.
Context.init(Func->getEntryNode());
Context.setInsertPoint(Context.getCur());
for (SizeT I = 0, E = Args.size(); I < E; ++I) {
Variable *Arg = Args[I];
Type Ty = Arg->getType();
RegNumT RegNum;
if (!CC.argInReg(Ty, I, &RegNum)) {
continue;
}
Variable *RegisterArg = Func->makeVariable(Ty);
if (BuildDefs::dump()) {
RegisterArg->setName(Func, "home_reg:" + Arg->getName());
}
RegisterArg->setIsArg();
Arg->setIsArg(false);
Args[I] = RegisterArg;
switch (Ty) {
default: { RegisterArg->setRegNum(RegNum); } break;
case IceType_i64: {
auto *RegisterArg64 = llvm::cast<Variable64On32>(RegisterArg);
RegisterArg64->initHiLo(Func);
RegisterArg64->getLo()->setRegNum(
RegNumT::fixme(RegMIPS32::getI64PairFirstGPRNum(RegNum)));
RegisterArg64->getHi()->setRegNum(
RegNumT::fixme(RegMIPS32::getI64PairSecondGPRNum(RegNum)));
} break;
}
Context.insert<InstAssign>(Arg, RegisterArg);
}
}
Type TargetMIPS32::stackSlotType() { return IceType_i32; }
// Helper function for addProlog().
//
// This assumes Arg is an argument passed on the stack. This sets the frame
// offset for Arg and updates InArgsSizeBytes according to Arg's width. For an
// I64 arg that has been split into Lo and Hi components, it calls itself
// recursively on the components, taking care to handle Lo first because of the
// little-endian architecture. Lastly, this function generates an instruction
// to copy Arg into its assigned register if applicable.
void TargetMIPS32::finishArgumentLowering(Variable *Arg, Variable *FramePtr,
size_t BasicFrameOffset,
size_t *InArgsSizeBytes) {
const Type Ty = Arg->getType();
*InArgsSizeBytes = applyStackAlignmentTy(*InArgsSizeBytes, Ty);
if (auto *Arg64On32 = llvm::dyn_cast<Variable64On32>(Arg)) {
Variable *const Lo = Arg64On32->getLo();
Variable *const Hi = Arg64On32->getHi();
finishArgumentLowering(Lo, FramePtr, BasicFrameOffset, InArgsSizeBytes);
finishArgumentLowering(Hi, FramePtr, BasicFrameOffset, InArgsSizeBytes);
return;
}
assert(Ty != IceType_i64);
const int32_t ArgStackOffset = BasicFrameOffset + *InArgsSizeBytes;
*InArgsSizeBytes += typeWidthInBytesOnStack(Ty);
if (!Arg->hasReg()) {
Arg->setStackOffset(ArgStackOffset);
return;
}
// If the argument variable has been assigned a register, we need to copy the
// value from the stack slot.
Variable *Parameter = Func->makeVariable(Ty);
Parameter->setMustNotHaveReg();
Parameter->setStackOffset(ArgStackOffset);
_mov(Arg, Parameter);
}
void TargetMIPS32::addProlog(CfgNode *Node) {
// Stack frame layout:
//
// +------------------------+
// | 1. preserved registers |
// +------------------------+
// | 2. padding |
// +------------------------+
// | 3. global spill area |
// +------------------------+
// | 4. padding |
// +------------------------+
// | 5. local spill area |
// +------------------------+
// | 6. padding |
// +------------------------+
// | 7. allocas |
// +------------------------+
// | 8. padding |
// +------------------------+
// | 9. out args |
// +------------------------+ <--- StackPointer
//
// The following variables record the size in bytes of the given areas:
// * PreservedRegsSizeBytes: area 1
// * SpillAreaPaddingBytes: area 2
// * GlobalsSize: area 3
// * GlobalsAndSubsequentPaddingSize: areas 3 - 4
// * LocalsSpillAreaSize: area 5
// * SpillAreaSizeBytes: areas 2 - 9
// * maxOutArgsSizeBytes(): area 9
Context.init(Node);
Context.setInsertPoint(Context.getCur());
SmallBitVector CalleeSaves = getRegisterSet(RegSet_CalleeSave, RegSet_None);
RegsUsed = SmallBitVector(CalleeSaves.size());
VarList SortedSpilledVariables;
size_t GlobalsSize = 0;
// If there is a separate locals area, this represents that area. Otherwise
// it counts any variable not counted by GlobalsSize.
SpillAreaSizeBytes = 0;
// If there is a separate locals area, this specifies the alignment for it.
uint32_t LocalsSlotsAlignmentBytes = 0;
// The entire spill locations area gets aligned to largest natural alignment
// of the variables that have a spill slot.
uint32_t SpillAreaAlignmentBytes = 0;
// For now, we don't have target-specific variables that need special
// treatment (no stack-slot-linked SpillVariable type).
std::function<bool(Variable *)> TargetVarHook = [](Variable *Var) {
static constexpr bool AssignStackSlot = false;
static constexpr bool DontAssignStackSlot = !AssignStackSlot;
if (llvm::isa<Variable64On32>(Var)) {
return DontAssignStackSlot;
}
return AssignStackSlot;
};
// Compute the list of spilled variables and bounds for GlobalsSize, etc.
getVarStackSlotParams(SortedSpilledVariables, RegsUsed, &GlobalsSize,
&SpillAreaSizeBytes, &SpillAreaAlignmentBytes,
&LocalsSlotsAlignmentBytes, TargetVarHook);
uint32_t LocalsSpillAreaSize = SpillAreaSizeBytes;
SpillAreaSizeBytes += GlobalsSize;
PreservedGPRs.reserve(CalleeSaves.size());
// Consider FP and RA as callee-save / used as needed.
if (UsesFramePointer) {
if (RegsUsed[RegMIPS32::Reg_FP]) {
llvm::report_fatal_error("Frame pointer has been used.");
}
CalleeSaves[RegMIPS32::Reg_FP] = true;
RegsUsed[RegMIPS32::Reg_FP] = true;
}
if (!MaybeLeafFunc) {
CalleeSaves[RegMIPS32::Reg_RA] = true;
RegsUsed[RegMIPS32::Reg_RA] = true;
}
// Make two passes over the used registers. The first pass records all the
// used registers -- and their aliases. Then, we figure out which GPR
// registers should be saved.
SmallBitVector ToPreserve(RegMIPS32::Reg_NUM);
for (SizeT i = 0; i < CalleeSaves.size(); ++i) {
if (CalleeSaves[i] && RegsUsed[i]) {
ToPreserve |= RegisterAliases[i];
}
}
uint32_t NumCallee = 0;
// RegClasses is a tuple of
//
// <First Register in Class, Last Register in Class, Vector of Save Registers>
//
// We use this tuple to figure out which register we should save/restore
// during
// prolog/epilog.
using RegClassType = std::tuple<uint32_t, uint32_t, VarList *>;
const RegClassType RegClass = RegClassType(
RegMIPS32::Reg_GPR_First, RegMIPS32::Reg_GPR_Last, &PreservedGPRs);
const uint32_t FirstRegInClass = std::get<0>(RegClass);
const uint32_t LastRegInClass = std::get<1>(RegClass);
VarList *const PreservedRegsInClass = std::get<2>(RegClass);
for (uint32_t Reg = LastRegInClass; Reg > FirstRegInClass; Reg--) {
if (!ToPreserve[Reg]) {
continue;
}
++NumCallee;
Variable *PhysicalRegister = getPhysicalRegister(RegNumT::fromInt(Reg));
PreservedRegsSizeBytes +=
typeWidthInBytesOnStack(PhysicalRegister->getType());
PreservedRegsInClass->push_back(PhysicalRegister);
}
Ctx->statsUpdateRegistersSaved(NumCallee);
// Align the variables area. SpillAreaPaddingBytes is the size of the region
// after the preserved registers and before the spill areas.
// LocalsSlotsPaddingBytes is the amount of padding between the globals and
// locals area if they are separate.
assert(SpillAreaAlignmentBytes <= MIPS32_STACK_ALIGNMENT_BYTES);
(void)MIPS32_STACK_ALIGNMENT_BYTES;
assert(LocalsSlotsAlignmentBytes <= SpillAreaAlignmentBytes);
uint32_t SpillAreaPaddingBytes = 0;
uint32_t LocalsSlotsPaddingBytes = 0;
alignStackSpillAreas(PreservedRegsSizeBytes, SpillAreaAlignmentBytes,
GlobalsSize, LocalsSlotsAlignmentBytes,
&SpillAreaPaddingBytes, &LocalsSlotsPaddingBytes);
SpillAreaSizeBytes += SpillAreaPaddingBytes + LocalsSlotsPaddingBytes;
uint32_t GlobalsAndSubsequentPaddingSize =
GlobalsSize + LocalsSlotsPaddingBytes;
// Adds the out args space to the stack, and align SP if necessary.
TotalStackSizeBytes = PreservedRegsSizeBytes + SpillAreaSizeBytes +
FixedAllocaSizeBytes + MaxOutArgsSizeBytes;
// Generate "addiu sp, sp, -TotalStackSizeBytes"
if (TotalStackSizeBytes) {
// Use the scratch register if needed to legalize the immediate.
Variable *SP = getPhysicalRegister(RegMIPS32::Reg_SP);
_addiu(SP, SP, -(TotalStackSizeBytes));
}
Ctx->statsUpdateFrameBytes(TotalStackSizeBytes);
if (!PreservedGPRs.empty()) {
uint32_t StackOffset = TotalStackSizeBytes;
for (Variable *Var : *PreservedRegsInClass) {
Variable *PhysicalRegister = getPhysicalRegister(Var->getRegNum());
StackOffset -= typeWidthInBytesOnStack(PhysicalRegister->getType());
Variable *SP = getPhysicalRegister(RegMIPS32::Reg_SP);
OperandMIPS32Mem *MemoryLocation = OperandMIPS32Mem::create(
Func, IceType_i32, SP,
llvm::cast<ConstantInteger32>(Ctx->getConstantInt32(StackOffset)));
_sw(PhysicalRegister, MemoryLocation);
}
}
Variable *FP = getPhysicalRegister(RegMIPS32::Reg_FP);
// Generate "mov FP, SP" if needed.
if (UsesFramePointer) {
Variable *SP = getPhysicalRegister(RegMIPS32::Reg_SP);
_mov(FP, SP);
// Keep FP live for late-stage liveness analysis (e.g. asm-verbose mode).
Context.insert<InstFakeUse>(FP);
}
// Fill in stack offsets for stack args, and copy args into registers for
// those that were register-allocated. Args are pushed right to left, so
// Arg[0] is closest to the stack/frame pointer.
const VarList &Args = Func->getArgs();
size_t InArgsSizeBytes = MIPS32_MAX_GPR_ARG * 4;
TargetMIPS32::CallingConv CC;
uint32_t ArgNo = 0;
for (Variable *Arg : Args) {
RegNumT DummyReg;
const Type Ty = Arg->getType();
// Skip arguments passed in registers.
if (CC.argInReg(Ty, ArgNo, &DummyReg)) {
ArgNo++;
continue;
} else {
finishArgumentLowering(Arg, FP, TotalStackSizeBytes, &InArgsSizeBytes);
}
}
// Fill in stack offsets for locals.
assignVarStackSlots(SortedSpilledVariables, SpillAreaPaddingBytes,
SpillAreaSizeBytes, GlobalsAndSubsequentPaddingSize,
UsesFramePointer);
this->HasComputedFrame = true;
if (BuildDefs::dump() && Func->isVerbose(IceV_Frame)) {
OstreamLocker _(Func->getContext());
Ostream &Str = Func->getContext()->getStrDump();
Str << "Stack layout:\n";
uint32_t SPAdjustmentPaddingSize =
SpillAreaSizeBytes - LocalsSpillAreaSize -
GlobalsAndSubsequentPaddingSize - SpillAreaPaddingBytes -
MaxOutArgsSizeBytes;
Str << " in-args = " << InArgsSizeBytes << " bytes\n"
<< " preserved registers = " << PreservedRegsSizeBytes << " bytes\n"
<< " spill area padding = " << SpillAreaPaddingBytes << " bytes\n"
<< " globals spill area = " << GlobalsSize << " bytes\n"
<< " globals-locals spill areas intermediate padding = "
<< GlobalsAndSubsequentPaddingSize - GlobalsSize << " bytes\n"
<< " locals spill area = " << LocalsSpillAreaSize << " bytes\n"
<< " SP alignment padding = " << SPAdjustmentPaddingSize << " bytes\n";
Str << "Stack details:\n"
<< " SP adjustment = " << SpillAreaSizeBytes << " bytes\n"
<< " spill area alignment = " << SpillAreaAlignmentBytes << " bytes\n"
<< " outgoing args size = " << MaxOutArgsSizeBytes << " bytes\n"
<< " locals spill area alignment = " << LocalsSlotsAlignmentBytes
<< " bytes\n"
<< " is FP based = " << 1 << "\n";
}
return;
}
void TargetMIPS32::addEpilog(CfgNode *Node) {
InstList &Insts = Node->getInsts();
InstList::reverse_iterator RI, E;
for (RI = Insts.rbegin(), E = Insts.rend(); RI != E; ++RI) {
if (llvm::isa<InstMIPS32Ret>(*RI))
break;
}
if (RI == E)
return;
// Convert the reverse_iterator position into its corresponding (forward)
// iterator position.
InstList::iterator InsertPoint = RI.base();
--InsertPoint;
Context.init(Node);
Context.setInsertPoint(InsertPoint);
Variable *SP = getPhysicalRegister(RegMIPS32::Reg_SP);
if (UsesFramePointer) {
Variable *FP = getPhysicalRegister(RegMIPS32::Reg_FP);
// For late-stage liveness analysis (e.g. asm-verbose mode), adding a fake
// use of SP before the assignment of SP=FP keeps previous SP adjustments
// from being dead-code eliminated.
Context.insert<InstFakeUse>(SP);
_mov(SP, FP);
}
VarList::reverse_iterator RIter, END;
if (!PreservedGPRs.empty()) {
uint32_t StackOffset = TotalStackSizeBytes - PreservedRegsSizeBytes;
for (RIter = PreservedGPRs.rbegin(), END = PreservedGPRs.rend();
RIter != END; ++RIter) {
Variable *PhysicalRegister = getPhysicalRegister((*RIter)->getRegNum());
Variable *SP = getPhysicalRegister(RegMIPS32::Reg_SP);
OperandMIPS32Mem *MemoryLocation = OperandMIPS32Mem::create(
Func, IceType_i32, SP,
llvm::cast<ConstantInteger32>(Ctx->getConstantInt32(StackOffset)));
_lw(PhysicalRegister, MemoryLocation);
StackOffset += typeWidthInBytesOnStack(PhysicalRegister->getType());
}
}
if (TotalStackSizeBytes) {
_addiu(SP, SP, TotalStackSizeBytes);
}
return;
}
Operand *TargetMIPS32::loOperand(Operand *Operand) {
assert(Operand->getType() == IceType_i64);
if (auto *Var64On32 = llvm::dyn_cast<Variable64On32>(Operand))
return Var64On32->getLo();
if (auto *Const = llvm::dyn_cast<ConstantInteger64>(Operand)) {
return Ctx->getConstantInt32(static_cast<uint32_t>(Const->getValue()));
}
if (auto *Mem = llvm::dyn_cast<OperandMIPS32Mem>(Operand)) {
// Conservatively disallow memory operands with side-effects (pre/post
// increment) in case of duplication.
assert(Mem->getAddrMode() == OperandMIPS32Mem::Offset);
return OperandMIPS32Mem::create(Func, IceType_i32, Mem->getBase(),
Mem->getOffset(), Mem->getAddrMode());
}
llvm_unreachable("Unsupported operand type");
return nullptr;
}
Operand *TargetMIPS32::hiOperand(Operand *Operand) {
assert(Operand->getType() == IceType_i64);
if (Operand->getType() != IceType_i64)
return Operand;
if (auto *Var64On32 = llvm::dyn_cast<Variable64On32>(Operand))
return Var64On32->getHi();
if (auto *Const = llvm::dyn_cast<ConstantInteger64>(Operand)) {
return Ctx->getConstantInt32(
static_cast<uint32_t>(Const->getValue() >> 32));
}
if (auto *Mem = llvm::dyn_cast<OperandMIPS32Mem>(Operand)) {
// Conservatively disallow memory operands with side-effects
// in case of duplication.
assert(Mem->getAddrMode() == OperandMIPS32Mem::Offset);
const Type SplitType = IceType_i32;
Variable *Base = Mem->getBase();
ConstantInteger32 *Offset = Mem->getOffset();
assert(!Utils::WouldOverflowAdd(Offset->getValue(), 4));
int32_t NextOffsetVal = Offset->getValue() + 4;
constexpr bool SignExt = false;
if (!OperandMIPS32Mem::canHoldOffset(SplitType, SignExt, NextOffsetVal)) {
// We have to make a temp variable and add 4 to either Base or Offset.
// If we add 4 to Offset, this will convert a non-RegReg addressing
// mode into a RegReg addressing mode. Since NaCl sandboxing disallows
// RegReg addressing modes, prefer adding to base and replacing instead.
// Thus we leave the old offset alone.
Constant *Four = Ctx->getConstantInt32(4);
Variable *NewBase = Func->makeVariable(Base->getType());
lowerArithmetic(InstArithmetic::create(Func, InstArithmetic::Add, NewBase,
Base, Four));
Base = NewBase;
} else {
Offset =
llvm::cast<ConstantInteger32>(Ctx->getConstantInt32(NextOffsetVal));
}
return OperandMIPS32Mem::create(Func, SplitType, Base, Offset,
Mem->getAddrMode());
}
llvm_unreachable("Unsupported operand type");
return nullptr;
}
SmallBitVector TargetMIPS32::getRegisterSet(RegSetMask Include,
RegSetMask Exclude) const {
SmallBitVector Registers(RegMIPS32::Reg_NUM);
#define X(val, encode, name, scratch, preserved, stackptr, frameptr, isInt, \
isI64Pair, isFP32, isFP64, isVec128, alias_init) \
if (scratch && (Include & RegSet_CallerSave)) \
Registers[RegMIPS32::val] = true; \
if (preserved && (Include & RegSet_CalleeSave)) \
Registers[RegMIPS32::val] = true; \
if (stackptr && (Include & RegSet_StackPointer)) \
Registers[RegMIPS32::val] = true; \
if (frameptr && (Include & RegSet_FramePointer)) \
Registers[RegMIPS32::val] = true; \
if (scratch && (Exclude & RegSet_CallerSave)) \
Registers[RegMIPS32::val] = false; \
if (preserved && (Exclude & RegSet_CalleeSave)) \
Registers[RegMIPS32::val] = false; \
if (stackptr && (Exclude & RegSet_StackPointer)) \
Registers[RegMIPS32::val] = false; \
if (frameptr && (Exclude & RegSet_FramePointer)) \
Registers[RegMIPS32::val] = false;
REGMIPS32_TABLE
#undef X
return Registers;
}
void TargetMIPS32::lowerAlloca(const InstAlloca *Instr) {
// Conservatively require the stack to be aligned. Some stack adjustment
// operations implemented below assume that the stack is aligned before the
// alloca. All the alloca code ensures that the stack alignment is preserved
// after the alloca. The stack alignment restriction can be relaxed in some
// cases.
NeedsStackAlignment = true;
// For default align=0, set it to the real value 1, to avoid any
// bit-manipulation problems below.
const uint32_t AlignmentParam = std::max(1u, Instr->getAlignInBytes());
// LLVM enforces power of 2 alignment.
assert(llvm::isPowerOf2_32(AlignmentParam));
assert(llvm::isPowerOf2_32(MIPS32_STACK_ALIGNMENT_BYTES));
const uint32_t Alignment =
std::max(AlignmentParam, MIPS32_STACK_ALIGNMENT_BYTES);
const bool OverAligned = Alignment > MIPS32_STACK_ALIGNMENT_BYTES;
const bool OptM1 = getFlags().getOptLevel() == Opt_m1;
const bool AllocaWithKnownOffset = Instr->getKnownFrameOffset();
const bool UseFramePointer =
hasFramePointer() || OverAligned || !AllocaWithKnownOffset || OptM1;
if (UseFramePointer)
setHasFramePointer();
Variable *SP = getPhysicalRegister(RegMIPS32::Reg_SP);
Variable *Dest = Instr->getDest();
Operand *TotalSize = Instr->getSizeInBytes();
if (const auto *ConstantTotalSize =
llvm::dyn_cast<ConstantInteger32>(TotalSize)) {
const uint32_t Value =
Utils::applyAlignment(ConstantTotalSize->getValue(), Alignment);
FixedAllocaSizeBytes += Value;
// Constant size alloca.
if (!UseFramePointer) {
// If we don't need a Frame Pointer, this alloca has a known offset to the
// stack pointer. We don't need adjust the stack pointer, nor assign any
// value to Dest, as Dest is rematerializable.
assert(Dest->isRematerializable());
Context.insert<InstFakeDef>(Dest);
return;
}
} else {
UnimplementedLoweringError(this, Instr);
return;
}
// Add enough to the returned address to account for the out args area.
if (MaxOutArgsSizeBytes > 0) {
Variable *T = makeReg(getPointerType());
_addiu(T, SP, MaxOutArgsSizeBytes);
_mov(Dest, T);
} else {
_mov(Dest, SP);
}
}
void TargetMIPS32::lowerInt64Arithmetic(const InstArithmetic *Instr,
Variable *Dest, Operand *Src0,
Operand *Src1) {
InstArithmetic::OpKind Op = Instr->getOp();
switch (Op) {
case InstArithmetic::Add:
case InstArithmetic::And:
case InstArithmetic::Or:
case InstArithmetic::Sub:
case InstArithmetic::Xor:
case InstArithmetic::Mul:
break;
default:
UnimplementedLoweringError(this, Instr);
return;
}
auto *DestLo = llvm::cast<Variable>(loOperand(Dest));
auto *DestHi = llvm::cast<Variable>(hiOperand(Dest));
Variable *Src0LoR = legalizeToReg(loOperand(Src0));
Variable *Src1LoR = legalizeToReg(loOperand(Src1));
Variable *Src0HiR = legalizeToReg(hiOperand(Src0));
Variable *Src1HiR = legalizeToReg(hiOperand(Src1));
switch (Op) {
case InstArithmetic::_num:
llvm::report_fatal_error("Unknown arithmetic operator");
return;
case InstArithmetic::Add: {
auto *T_Carry = I32Reg(), *T_Lo = I32Reg(), *T_Hi = I32Reg(),
*T_Hi2 = I32Reg();
_addu(T_Lo, Src0LoR, Src1LoR);
_mov(DestLo, T_Lo);
_sltu(T_Carry, T_Lo, Src0LoR);
_addu(T_Hi, T_Carry, Src0HiR);
_addu(T_Hi2, Src1HiR, T_Hi);
_mov(DestHi, T_Hi2);
return;
}
case InstArithmetic::And: {
auto *T_Lo = I32Reg(), *T_Hi = I32Reg();
_and(T_Lo, Src0LoR, Src1LoR);
_mov(DestLo, T_Lo);
_and(T_Hi, Src0HiR, Src1HiR);
_mov(DestHi, T_Hi);
return;
}
case InstArithmetic::Sub: {
auto *T_Borrow = I32Reg(), *T_Lo = I32Reg(), *T_Hi = I32Reg(),
*T_Hi2 = I32Reg();
_subu(T_Lo, Src0LoR, Src1LoR);
_mov(DestLo, T_Lo);
_sltu(T_Borrow, Src0LoR, Src1LoR);
_addu(T_Hi, T_Borrow, Src1HiR);
_subu(T_Hi2, Src0HiR, T_Hi);
_mov(DestHi, T_Hi2);
return;
}
case InstArithmetic::Or: {
auto *T_Lo = I32Reg(), *T_Hi = I32Reg();
_or(T_Lo, Src0LoR, Src1LoR);
_mov(DestLo, T_Lo);
_or(T_Hi, Src0HiR, Src1HiR);
_mov(DestHi, T_Hi);
return;
}
case InstArithmetic::Xor: {
auto *T_Lo = I32Reg(), *T_Hi = I32Reg();
_xor(T_Lo, Src0LoR, Src1LoR);
_mov(DestLo, T_Lo);
_xor(T_Hi, Src0HiR, Src1HiR);
_mov(DestHi, T_Hi);
return;
}
case InstArithmetic::Mul: {
// TODO(rkotler): Make sure that mul has the side effect of clobbering
// LO, HI. Check for any other LO, HI quirkiness in this section.
auto *T_Lo = I32Reg(RegMIPS32::Reg_LO), *T_Hi = I32Reg(RegMIPS32::Reg_HI);
auto *T1 = I32Reg(), *T2 = I32Reg();
auto *TM1 = I32Reg(), *TM2 = I32Reg(), *TM3 = I32Reg(), *TM4 = I32Reg();
_multu(T_Lo, Src0LoR, Src1LoR);
Context.insert<InstFakeDef>(T_Hi, T_Lo);
_mflo(T1, T_Lo);
_mfhi(T2, T_Hi);
_mov(DestLo, T1);
_mul(TM1, Src0HiR, Src1LoR);
_mul(TM2, Src0LoR, Src1HiR);
_addu(TM3, TM1, T2);
_addu(TM4, TM3, TM2);
_mov(DestHi, TM4);
return;
}
default:
UnimplementedLoweringError(this, Instr);
return;
}
}
void TargetMIPS32::lowerArithmetic(const InstArithmetic *Instr) {
Variable *Dest = Instr->getDest();
// We need to signal all the UnimplementedLoweringError errors before any
// legalization into new variables, otherwise Om1 register allocation may fail
// when it sees variables that are defined but not used.
Type DestTy = Dest->getType();
Operand *Src0 = legalizeUndef(Instr->getSrc(0));
Operand *Src1 = legalizeUndef(Instr->getSrc(1));
if (DestTy == IceType_i64) {
lowerInt64Arithmetic(Instr, Instr->getDest(), Src0, Src1);
return;
}
if (isVectorType(Dest->getType())) {
UnimplementedLoweringError(this, Instr);
return;
}
switch (Instr->getOp()) {
default:
break;
case InstArithmetic::Fadd:
case InstArithmetic::Fsub:
case InstArithmetic::Fmul:
case InstArithmetic::Fdiv:
case InstArithmetic::Frem:
UnimplementedLoweringError(this, Instr);
return;
}
// At this point Dest->getType() is non-i64 scalar
Variable *T = makeReg(Dest->getType());
Variable *Src0R = legalizeToReg(Src0);
Variable *Src1R = legalizeToReg(Src1);
switch (Instr->getOp()) {
case InstArithmetic::_num:
break;
case InstArithmetic::Add:
_addu(T, Src0R, Src1R);
_mov(Dest, T);
return;
case InstArithmetic::And:
_and(T, Src0R, Src1R);
_mov(Dest, T);
return;
case InstArithmetic::Or:
_or(T, Src0R, Src1R);
_mov(Dest, T);
return;
case InstArithmetic::Xor:
_xor(T, Src0R, Src1R);
_mov(Dest, T);
return;
case InstArithmetic::Sub:
_subu(T, Src0R, Src1R);
_mov(Dest, T);
return;
case InstArithmetic::Mul: {
_mul(T, Src0R, Src1R);
_mov(Dest, T);
return;
}
case InstArithmetic::Shl: {
_sllv(T, Src0R, Src1R);
_mov(Dest, T);
return;
}
case InstArithmetic::Lshr: {
_srlv(T, Src0R, Src1R);
_mov(Dest, T);
return;
}
case InstArithmetic::Ashr: {
_srav(T, Src0R, Src1R);
_mov(Dest, T);
return;
}
case InstArithmetic::Udiv: {
auto *T_Zero = I32Reg(RegMIPS32::Reg_ZERO);
_divu(T_Zero, Src0R, Src1R);
_mflo(T, T_Zero);
_mov(Dest, T);
return;
}
case InstArithmetic::Sdiv: {
auto *T_Zero = I32Reg(RegMIPS32::Reg_ZERO);
_div(T_Zero, Src0R, Src1R);
_mflo(T, T_Zero);
_mov(Dest, T);
return;
}
case InstArithmetic::Urem: {
auto *T_Zero = I32Reg(RegMIPS32::Reg_ZERO);
_divu(T_Zero, Src0R, Src1R);
_mfhi(T, T_Zero);
_mov(Dest, T);
return;
}
case InstArithmetic::Srem: {
auto *T_Zero = I32Reg(RegMIPS32::Reg_ZERO);
_div(T_Zero, Src0R, Src1R);
_mfhi(T, T_Zero);
_mov(Dest, T);
return;
}
case InstArithmetic::Fadd:
break;
case InstArithmetic::Fsub:
break;
case InstArithmetic::Fmul:
break;
case InstArithmetic::Fdiv:
break;
case InstArithmetic::Frem:
break;
}
UnimplementedLoweringError(this, Instr);
}
void TargetMIPS32::lowerAssign(const InstAssign *Instr) {
Variable *Dest = Instr->getDest();
Operand *Src0 = Instr->getSrc(0);
assert(Dest->getType() == Src0->getType());
if (Dest->getType() == IceType_i64) {
Src0 = legalizeUndef(Src0);
Operand *Src0Lo = legalize(loOperand(Src0), Legal_Reg);
Operand *Src0Hi = legalize(hiOperand(Src0), Legal_Reg);
auto *DestLo = llvm::cast<Variable>(loOperand(Dest));
auto *DestHi = llvm::cast<Variable>(hiOperand(Dest));
// Variable *T_Lo = nullptr, *T_Hi = nullptr;
auto *T_Lo = I32Reg(), *T_Hi = I32Reg();
_mov(T_Lo, Src0Lo);
_mov(DestLo, T_Lo);
_mov(T_Hi, Src0Hi);
_mov(DestHi, T_Hi);
} else {
Operand *SrcR;
if (Dest->hasReg()) {
// If Dest already has a physical register, then legalize the Src operand
// into a Variable with the same register assignment. This especially
// helps allow the use of Flex operands.
SrcR = legalize(Src0, Legal_Reg, Dest->getRegNum());
} else {
// Dest could be a stack operand. Since we could potentially need
// to do a Store (and store can only have Register operands),
// legalize this to a register.
SrcR = legalize(Src0, Legal_Reg);
}
if (isVectorType(Dest->getType())) {
UnimplementedLoweringError(this, Instr);
} else {
_mov(Dest, SrcR);
}
}
}
void TargetMIPS32::lowerBr(const InstBr *Instr) {
if (Instr->isUnconditional()) {
_br(Instr->getTargetUnconditional());
return;
}
CfgNode *TargetTrue = Instr->getTargetTrue();
CfgNode *TargetFalse = Instr->getTargetFalse();
Operand *Boolean = Instr->getCondition();
const Inst *Producer = Computations.getProducerOf(Boolean);
if (Producer == nullptr) {
// Since we don't know the producer of this boolean we will assume its
// producer will keep it in positive logic and just emit beqz with this
// Boolean as an operand.
auto *BooleanR = legalizeToReg(Boolean);
_br(TargetTrue, TargetFalse, BooleanR, CondMIPS32::Cond::EQZ);
return;
}
if (Producer->getKind() == Inst::Icmp) {
const InstIcmp *CompareInst = llvm::cast<InstIcmp>(Producer);
Operand *Src0 = CompareInst->getSrc(0);
Operand *Src1 = CompareInst->getSrc(1);
const Type Src0Ty = Src0->getType();
assert(Src0Ty == Src1->getType());
if (Src0Ty == IceType_i64) {
UnimplementedLoweringError(this, Instr);
return;
}
auto *Src0R = legalizeToReg(Src0);
auto *Src1R = legalizeToReg(Src1);
auto *DestT = makeReg(Src0Ty);
switch (CompareInst->getCondition()) {
default:
break;
case InstIcmp::Eq: {
_br(TargetTrue, TargetFalse, Src0R, Src1R, CondMIPS32::Cond::NE);
break;
}
case InstIcmp::Ne: {
_br(TargetTrue, TargetFalse, Src0R, Src1R, CondMIPS32::Cond::EQ);
break;
}
case InstIcmp::Ugt: {
_sltu(DestT, Src1R, Src0R);
_br(TargetTrue, TargetFalse, DestT, CondMIPS32::Cond::EQZ);
break;
}
case InstIcmp::Uge: {
_sltu(DestT, Src0R, Src1R);
_br(TargetTrue, TargetFalse, DestT, CondMIPS32::Cond::NEZ);
break;
}
case InstIcmp::Ult: {
_sltu(DestT, Src0R, Src1R);
_br(TargetTrue, TargetFalse, DestT, CondMIPS32::Cond::EQZ);
break;
}
case InstIcmp::Ule: {
_sltu(DestT, Src1R, Src0R);
_br(TargetTrue, TargetFalse, DestT, CondMIPS32::Cond::NEZ);
break;
}
case InstIcmp::Sgt: {
_slt(DestT, Src1R, Src0R);
_br(TargetTrue, TargetFalse, DestT, CondMIPS32::Cond::EQZ);
break;
}
case InstIcmp::Sge: {
_slt(DestT, Src0R, Src1R);
_br(TargetTrue, TargetFalse, DestT, CondMIPS32::Cond::NEZ);
break;
}
case InstIcmp::Slt: {
_slt(DestT, Src0R, Src1R);
_br(TargetTrue, TargetFalse, DestT, CondMIPS32::Cond::EQZ);
break;
}
case InstIcmp::Sle: {
_slt(DestT, Src1R, Src0R);
_br(TargetTrue, TargetFalse, DestT, CondMIPS32::Cond::NEZ);
break;
}
}
}
}
void TargetMIPS32::lowerCall(const InstCall *Instr) {
NeedsStackAlignment = true;
// Assign arguments to registers and stack. Also reserve stack.
TargetMIPS32::CallingConv CC;
// Pair of Arg Operand -> GPR number assignments.
llvm::SmallVector<std::pair<Operand *, RegNumT>, MIPS32_MAX_GPR_ARG> GPRArgs;
llvm::SmallVector<std::pair<Operand *, RegNumT>, MIPS32_MAX_FP_ARG> FPArgs;
// Pair of Arg Operand -> stack offset.
llvm::SmallVector<std::pair<Operand *, int32_t>, 8> StackArgs;
size_t ParameterAreaSizeBytes = 16;
// Classify each argument operand according to the location where the
// argument is passed.
for (SizeT i = 0, NumArgs = Instr->getNumArgs(); i < NumArgs; ++i) {
Operand *Arg = legalizeUndef(Instr->getArg(i));
const Type Ty = Arg->getType();
bool InReg = false;
RegNumT Reg;
InReg = CC.argInReg(Ty, i, &Reg);
if (!InReg) {
ParameterAreaSizeBytes =
applyStackAlignmentTy(ParameterAreaSizeBytes, Ty);
StackArgs.push_back(std::make_pair(Arg, ParameterAreaSizeBytes));
ParameterAreaSizeBytes += typeWidthInBytesOnStack(Ty);
continue;
}
if (Ty == IceType_i64) {
Operand *Lo = loOperand(Arg);
Operand *Hi = hiOperand(Arg);
GPRArgs.push_back(
std::make_pair(Lo, RegMIPS32::getI64PairFirstGPRNum(Reg)));
GPRArgs.push_back(
std::make_pair(Hi, RegMIPS32::getI64PairSecondGPRNum(Reg)));
} else if (isScalarIntegerType(Ty)) {
GPRArgs.push_back(std::make_pair(Arg, Reg));
} else {
FPArgs.push_back(std::make_pair(Arg, Reg));
}
}
// Adjust the parameter area so that the stack is aligned. It is assumed that
// the stack is already aligned at the start of the calling sequence.
ParameterAreaSizeBytes = applyStackAlignment(ParameterAreaSizeBytes);
// Copy arguments that are passed on the stack to the appropriate stack
// locations.
Variable *SP = getPhysicalRegister(RegMIPS32::Reg_SP);
for (auto &StackArg : StackArgs) {
ConstantInteger32 *Loc =
llvm::cast<ConstantInteger32>(Ctx->getConstantInt32(StackArg.second));
Type Ty = StackArg.first->getType();
OperandMIPS32Mem *Addr;
constexpr bool SignExt = false;
if (OperandMIPS32Mem::canHoldOffset(Ty, SignExt, StackArg.second)) {
Addr = OperandMIPS32Mem::create(Func, Ty, SP, Loc);
} else {
Variable *NewBase = Func->makeVariable(SP->getType());
lowerArithmetic(
InstArithmetic::create(Func, InstArithmetic::Add, NewBase, SP, Loc));
Addr = formMemoryOperand(NewBase, Ty);
}
lowerStore(InstStore::create(Func, StackArg.first, Addr));
}
// Generate the call instruction. Assign its result to a temporary with high
// register allocation weight.
Variable *Dest = Instr->getDest();
// ReturnReg doubles as ReturnRegLo as necessary.
Variable *ReturnReg = nullptr;
Variable *ReturnRegHi = nullptr;
if (Dest) {
switch (Dest->getType()) {
case IceType_NUM:
llvm_unreachable("Invalid Call dest type");
return;
case IceType_void:
break;
case IceType_i1:
case IceType_i8:
case IceType_i16:
case IceType_i32:
ReturnReg = makeReg(Dest->getType(), RegMIPS32::Reg_V0);
break;
case IceType_i64:
ReturnReg = I32Reg(RegMIPS32::Reg_V0);
ReturnRegHi = I32Reg(RegMIPS32::Reg_V1);
break;
case IceType_f32:
case IceType_f64:
UnimplementedLoweringError(this, Instr);
return;
case IceType_v4i1:
case IceType_v8i1:
case IceType_v16i1:
case IceType_v16i8:
case IceType_v8i16:
case IceType_v4i32:
case IceType_v4f32:
UnimplementedLoweringError(this, Instr);
return;
}
}
Operand *CallTarget = Instr->getCallTarget();
// Allow ConstantRelocatable to be left alone as a direct call,
// but force other constants like ConstantInteger32 to be in
// a register and make it an indirect call.
if (!llvm::isa<ConstantRelocatable>(CallTarget)) {
CallTarget = legalize(CallTarget, Legal_Reg);
}
// Copy arguments to be passed in registers to the appropriate registers.
CfgVector<Variable *> RegArgs;
for (auto &FPArg : FPArgs) {
RegArgs.emplace_back(legalizeToReg(FPArg.first, FPArg.second));
}
for (auto &GPRArg : GPRArgs) {
RegArgs.emplace_back(legalizeToReg(GPRArg.first, GPRArg.second));
}
// Generate a FakeUse of register arguments so that they do not get dead code
// eliminated as a result of the FakeKill of scratch registers after the call.
// These fake-uses need to be placed here to avoid argument registers from
// being used during the legalizeToReg() calls above.
for (auto *RegArg : RegArgs) {
Context.insert<InstFakeUse>(RegArg);
}
Inst *NewCall = InstMIPS32Call::create(Func, ReturnReg, CallTarget);
Context.insert(NewCall);
if (ReturnRegHi)
Context.insert(InstFakeDef::create(Func, ReturnRegHi));
// Insert a register-kill pseudo instruction.
Context.insert(InstFakeKill::create(Func, NewCall));
// Generate a FakeUse to keep the call live if necessary.
if (Instr->hasSideEffects() && ReturnReg) {
Context.insert<InstFakeUse>(ReturnReg);
}
if (Dest == nullptr)
return;
// Assign the result of the call to Dest.
if (ReturnReg) {
if (ReturnRegHi) {
assert(Dest->getType() == IceType_i64);
auto *Dest64On32 = llvm::cast<Variable64On32>(Dest);
Variable *DestLo = Dest64On32->getLo();
Variable *DestHi = Dest64On32->getHi();
_mov(DestLo, ReturnReg);
_mov(DestHi, ReturnRegHi);
} else {
assert(Dest->getType() == IceType_i32 || Dest->getType() == IceType_i16 ||
Dest->getType() == IceType_i8 || Dest->getType() == IceType_i1 ||
isVectorType(Dest->getType()));
if (isFloatingType(Dest->getType()) || isVectorType(Dest->getType())) {
UnimplementedLoweringError(this, Instr);
return;
} else {
_mov(Dest, ReturnReg);
}
}
}
}
void TargetMIPS32::lowerCast(const InstCast *Instr) {
InstCast::OpKind CastKind = Instr->getCastKind();
Variable *Dest = Instr->getDest();
Operand *Src0 = legalizeUndef(Instr->getSrc(0));
const Type DestTy = Dest->getType();
const Type Src0Ty = Src0->getType();
const uint32_t ShiftAmount =
(Src0Ty == IceType_i1
? INT32_BITS - 1
: INT32_BITS - (CHAR_BITS * typeWidthInBytes(Src0Ty)));
const uint32_t Mask =
(Src0Ty == IceType_i1
? 1
: (1 << (CHAR_BITS * typeWidthInBytes(Src0Ty))) - 1);
if (isVectorType(DestTy)) {
UnimplementedLoweringError(this, Instr);
return;
}
switch (CastKind) {
default:
Func->setError("Cast type not supported");
return;
case InstCast::Sext: {
if (DestTy == IceType_i64) {
auto *DestLo = llvm::cast<Variable>(loOperand(Dest));
auto *DestHi = llvm::cast<Variable>(hiOperand(Dest));
Variable *Src0R = legalizeToReg(Src0);
Variable *T1_Lo = I32Reg();
Variable *T2_Lo = I32Reg();
Variable *T_Hi = I32Reg();
if (Src0Ty == IceType_i1) {
_sll(T1_Lo, Src0R, INT32_BITS - 1);
_sra(T2_Lo, T1_Lo, INT32_BITS - 1);
_mov(DestHi, T2_Lo);
_mov(DestLo, T2_Lo);
} else if (Src0Ty == IceType_i8 || Src0Ty == IceType_i16) {
_sll(T1_Lo, Src0R, ShiftAmount);
_sra(T2_Lo, T1_Lo, ShiftAmount);
_sra(T_Hi, T2_Lo, INT32_BITS - 1);
_mov(DestHi, T_Hi);
_mov(DestLo, T2_Lo);
} else if (Src0Ty == IceType_i32) {
_mov(T1_Lo, Src0R);
_sra(T_Hi, T1_Lo, INT32_BITS - 1);
_mov(DestHi, T_Hi);
_mov(DestLo, T1_Lo);
}
} else {
Variable *Src0R = legalizeToReg(Src0);
Variable *T1 = makeReg(DestTy);
Variable *T2 = makeReg(DestTy);
if (Src0Ty == IceType_i1 || Src0Ty == IceType_i8 ||
Src0Ty == IceType_i16) {
_sll(T1, Src0R, ShiftAmount);
_sra(T2, T1, ShiftAmount);
_mov(Dest, T2);
}
}
break;
}
case InstCast::Zext: {
if (DestTy == IceType_i64) {
auto *DestLo = llvm::cast<Variable>(loOperand(Dest));
auto *DestHi = llvm::cast<Variable>(hiOperand(Dest));
Variable *Src0R = legalizeToReg(Src0);
Variable *T_Lo = I32Reg();
Variable *T_Hi = I32Reg();
if (Src0Ty == IceType_i1 || Src0Ty == IceType_i8 || Src0Ty == IceType_i16)
_andi(T_Lo, Src0R, Mask);
else if (Src0Ty == IceType_i32)
_mov(T_Lo, Src0R);
else
assert(Src0Ty != IceType_i64);
_mov(DestLo, T_Lo);
auto *Zero = getZero();
_addiu(T_Hi, Zero, 0);
_mov(DestHi, T_Hi);
} else {
Variable *Src0R = legalizeToReg(Src0);
Variable *T = makeReg(DestTy);
if (Src0Ty == IceType_i1 || Src0Ty == IceType_i8 ||
Src0Ty == IceType_i16) {
_andi(T, Src0R, Mask);
_mov(Dest, T);
}
}
break;
}
case InstCast::Trunc: {
if (Src0Ty == IceType_i64)
Src0 = loOperand(Src0);
Variable *Src0R = legalizeToReg(Src0);
Variable *T = makeReg(DestTy);
_mov(T, Src0R);
_mov(Dest, T);
break;
}
case InstCast::Fptrunc:
// Use _cvt_d_s
UnimplementedLoweringError(this, Instr);
break;
case InstCast::Fpext: {
// Use _cvt_s_d
UnimplementedLoweringError(this, Instr);
break;
}
case InstCast::Fptosi:
UnimplementedLoweringError(this, Instr);
break;
case InstCast::Fptoui:
UnimplementedLoweringError(this, Instr);
break;
case InstCast::Sitofp:
UnimplementedLoweringError(this, Instr);
break;
case InstCast::Uitofp: {
UnimplementedLoweringError(this, Instr);
break;
}
case InstCast::Bitcast: {
UnimplementedLoweringError(this, Instr);
break;
}
}
}
void TargetMIPS32::lowerExtractElement(const InstExtractElement *Instr) {
UnimplementedLoweringError(this, Instr);
}
void TargetMIPS32::lowerFcmp(const InstFcmp *Instr) {
UnimplementedLoweringError(this, Instr);
}
void TargetMIPS32::lower64Icmp(const InstIcmp *Instr) {
UnimplementedLoweringError(this, Instr);
return;
}
void TargetMIPS32::lowerIcmp(const InstIcmp *Instr) {
auto *Src0 = Instr->getSrc(0);
auto *Src1 = Instr->getSrc(1);
if (Src0->getType() == IceType_i64) {
lower64Icmp(Instr);
return;
}
Variable *Dest = Instr->getDest();
if (isVectorType(Dest->getType())) {
UnimplementedLoweringError(this, Instr);
return;
}
InstIcmp::ICond Cond = Instr->getCondition();
auto *Src0R = legalizeToReg(Src0);
auto *Src1R = legalizeToReg(Src1);
const Type Src0Ty = Src0R->getType();
const uint32_t ShAmt = INT32_BITS - getScalarIntBitWidth(Src0->getType());
Variable *Src0RT = I32Reg();
Variable *Src1RT = I32Reg();
if (Src0Ty != IceType_i32) {
_sll(Src0RT, Src0R, ShAmt);
_sll(Src1RT, Src1R, ShAmt);
} else {
_mov(Src0RT, Src0R);
_mov(Src1RT, Src1R);
}
switch (Cond) {
case InstIcmp::Eq: {
auto *DestT = I32Reg();
auto *T = I32Reg();
_xor(T, Src0RT, Src1RT);
_sltiu(DestT, T, 1);
_mov(Dest, DestT);
return;
}
case InstIcmp::Ne: {
auto *DestT = I32Reg();
auto *T = I32Reg();
auto *Zero = getZero();
_xor(T, Src0RT, Src1RT);
_sltu(DestT, Zero, T);
_mov(Dest, DestT);
return;
}
case InstIcmp::Ugt: {
auto *DestT = I32Reg();
_sltu(DestT, Src1RT, Src0RT);
_mov(Dest, DestT);
return;
}
case InstIcmp::Uge: {
auto *DestT = I32Reg();
auto *T = I32Reg();
_sltu(T, Src0RT, Src1RT);
_xori(DestT, T, 1);
_mov(Dest, DestT);
return;
}
case InstIcmp::Ult: {
auto *DestT = I32Reg();
_sltu(DestT, Src0RT, Src1RT);
_mov(Dest, DestT);
return;
}
case InstIcmp::Ule: {
auto *DestT = I32Reg();
auto *T = I32Reg();
_sltu(T, Src1RT, Src0RT);
_xori(DestT, T, 1);
_mov(Dest, DestT);
return;
}
case InstIcmp::Sgt: {
auto *DestT = I32Reg();
_slt(DestT, Src1RT, Src0RT);
_mov(Dest, DestT);
return;
}
case InstIcmp::Sge: {
auto *DestT = I32Reg();
auto *T = I32Reg();
_slt(T, Src0RT, Src1RT);
_xori(DestT, T, 1);
_mov(Dest, DestT);
return;
}
case InstIcmp::Slt: {
auto *DestT = I32Reg();
_slt(DestT, Src0RT, Src1RT);
_mov(Dest, DestT);
return;
}
case InstIcmp::Sle: {
auto *DestT = I32Reg();
auto *T = I32Reg();
_slt(T, Src1RT, Src0RT);
_xori(DestT, T, 1);
_mov(Dest, DestT);
return;
}
default:
llvm_unreachable("Invalid ICmp operator");
return;
}
}
void TargetMIPS32::lowerInsertElement(const InstInsertElement *Instr) {
UnimplementedLoweringError(this, Instr);
}
void TargetMIPS32::lowerIntrinsicCall(const InstIntrinsicCall *Instr) {
switch (Instr->getIntrinsicInfo().ID) {
case Intrinsics::AtomicCmpxchg: {
UnimplementedLoweringError(this, Instr);
return;
}
case Intrinsics::AtomicFence:
UnimplementedLoweringError(this, Instr);
return;
case Intrinsics::AtomicFenceAll:
// NOTE: FenceAll should prevent and load/store from being moved across the
// fence (both atomic and non-atomic). The InstMIPS32Mfence instruction is
// currently marked coarsely as "HasSideEffects".
UnimplementedLoweringError(this, Instr);
return;
case Intrinsics::AtomicIsLockFree: {
UnimplementedLoweringError(this, Instr);
return;
}
case Intrinsics::AtomicLoad: {
UnimplementedLoweringError(this, Instr);
return;
}
case Intrinsics::AtomicRMW:
UnimplementedLoweringError(this, Instr);
return;
case Intrinsics::AtomicStore: {
UnimplementedLoweringError(this, Instr);
return;
}
case Intrinsics::Bswap: {
UnimplementedLoweringError(this, Instr);
return;
}
case Intrinsics::Ctpop: {
UnimplementedLoweringError(this, Instr);
return;
}
case Intrinsics::Ctlz: {
UnimplementedLoweringError(this, Instr);
return;
}
case Intrinsics::Cttz: {
UnimplementedLoweringError(this, Instr);
return;
}
case Intrinsics::Fabs: {
UnimplementedLoweringError(this, Instr);
return;
}
case Intrinsics::Longjmp: {
InstCall *Call = makeHelperCall(RuntimeHelper::H_call_longjmp, nullptr, 2);
Call->addArg(Instr->getArg(0));
Call->addArg(Instr->getArg(1));
lowerCall(Call);
return;
}
case Intrinsics::Memcpy: {
// In the future, we could potentially emit an inline memcpy/memset, etc.
// for intrinsic calls w/ a known length.
InstCall *Call = makeHelperCall(RuntimeHelper::H_call_memcpy, nullptr, 3);
Call->addArg(Instr->getArg(0));
Call->addArg(Instr->getArg(1));
Call->addArg(Instr->getArg(2));
lowerCall(Call);
return;
}
case Intrinsics::Memmove: {
InstCall *Call = makeHelperCall(RuntimeHelper::H_call_memmove, nullptr, 3);
Call->addArg(Instr->getArg(0));
Call->addArg(Instr->getArg(1));
Call->addArg(Instr->getArg(2));
lowerCall(Call);
return;
}
case Intrinsics::Memset: {
// The value operand needs to be extended to a stack slot size because the
// PNaCl ABI requires arguments to be at least 32 bits wide.
Operand *ValOp = Instr->getArg(1);
assert(ValOp->getType() == IceType_i8);
Variable *ValExt = Func->makeVariable(stackSlotType());
lowerCast(InstCast::create(Func, InstCast::Zext, ValExt, ValOp));
InstCall *Call = makeHelperCall(RuntimeHelper::H_call_memset, nullptr, 3);
Call->addArg(Instr->getArg(0));
Call->addArg(ValExt);
Call->addArg(Instr->getArg(2));
lowerCall(Call);
return;
}
case Intrinsics::NaClReadTP: {
if (getFlags().getUseSandboxing()) {
UnimplementedLoweringError(this, Instr);
} else {
InstCall *Call =
makeHelperCall(RuntimeHelper::H_call_read_tp, Instr->getDest(), 0);
lowerCall(Call);
}
return;
}
case Intrinsics::Setjmp: {
InstCall *Call =
makeHelperCall(RuntimeHelper::H_call_setjmp, Instr->getDest(), 1);
Call->addArg(Instr->getArg(0));
lowerCall(Call);
return;
}
case Intrinsics::Sqrt: {
UnimplementedLoweringError(this, Instr);
return;
}
case Intrinsics::Stacksave: {
UnimplementedLoweringError(this, Instr);
return;
}
case Intrinsics::Stackrestore: {
UnimplementedLoweringError(this, Instr);
return;
}
case Intrinsics::Trap:
UnimplementedLoweringError(this, Instr);
return;
case Intrinsics::UnknownIntrinsic:
Func->setError("Should not be lowering UnknownIntrinsic");
return;
}
return;
}
void TargetMIPS32::lowerLoad(const InstLoad *Instr) {
UnimplementedLoweringError(this, Instr);
}
void TargetMIPS32::doAddressOptLoad() { UnimplementedError(getFlags()); }
void TargetMIPS32::randomlyInsertNop(float Probability,
RandomNumberGenerator &RNG) {
RandomNumberGeneratorWrapper RNGW(RNG);
if (RNGW.getTrueWithProbability(Probability)) {
UnimplementedError(getFlags());
}
}
void TargetMIPS32::lowerPhi(const InstPhi * /*Instr*/) {
Func->setError("Phi found in regular instruction list");
}
void TargetMIPS32::lowerRet(const InstRet *Instr) {
Variable *Reg = nullptr;
if (Instr->hasRetValue()) {
Operand *Src0 = Instr->getRetValue();
switch (Src0->getType()) {
case IceType_i1:
case IceType_i8:
case IceType_i16:
case IceType_i32: {
// Reg = legalizeToReg(Src0, RegMIPS32::Reg_V0);
Operand *Src0F = legalize(Src0, Legal_Reg);
Reg = makeReg(Src0F->getType(), RegMIPS32::Reg_V0);
_mov(Reg, Src0F);
break;
}
case IceType_i64: {
Src0 = legalizeUndef(Src0);
Variable *R0 = legalizeToReg(loOperand(Src0), RegMIPS32::Reg_V0);
Variable *R1 = legalizeToReg(hiOperand(Src0), RegMIPS32::Reg_V1);
Reg = R0;
Context.insert<InstFakeUse>(R1);
break;
}
default:
UnimplementedLoweringError(this, Instr);
}
}
_ret(getPhysicalRegister(RegMIPS32::Reg_RA), Reg);
}
void TargetMIPS32::lowerSelect(const InstSelect *Instr) {
UnimplementedLoweringError(this, Instr);
}
void TargetMIPS32::lowerShuffleVector(const InstShuffleVector *Instr) {
UnimplementedLoweringError(this, Instr);
}
void TargetMIPS32::lowerStore(const InstStore *Instr) {
Operand *Value = Instr->getData();
Operand *Addr = Instr->getAddr();
OperandMIPS32Mem *NewAddr = formMemoryOperand(Addr, Value->getType());
Type Ty = NewAddr->getType();
if (Ty == IceType_i64) {
Value = legalizeUndef(Value);
Variable *ValueHi = legalizeToReg(hiOperand(Value));
Variable *ValueLo = legalizeToReg(loOperand(Value));
_sw(ValueHi, llvm::cast<OperandMIPS32Mem>(hiOperand(NewAddr)));
_sw(ValueLo, llvm::cast<OperandMIPS32Mem>(loOperand(NewAddr)));
} else {
Variable *ValueR = legalizeToReg(Value);
_sw(ValueR, NewAddr);
}
}
void TargetMIPS32::doAddressOptStore() { UnimplementedError(getFlags()); }
void TargetMIPS32::lowerSwitch(const InstSwitch *Instr) {
UnimplementedLoweringError(this, Instr);
}
void TargetMIPS32::lowerBreakpoint(const InstBreakpoint *Instr) {
UnimplementedLoweringError(this, Instr);
}
void TargetMIPS32::lowerUnreachable(const InstUnreachable *Instr) {
UnimplementedLoweringError(this, Instr);
}
// Turn an i64 Phi instruction into a pair of i32 Phi instructions, to preserve
// integrity of liveness analysis. Undef values are also turned into zeroes,
// since loOperand() and hiOperand() don't expect Undef input.
void TargetMIPS32::prelowerPhis() {
PhiLowering::prelowerPhis32Bit<TargetMIPS32>(this, Context.getNode(), Func);
}
void TargetMIPS32::postLower() {
if (getFlags().getOptLevel() == Opt_m1)
return;
// TODO(rkotler): Find two-address non-SSA instructions where Dest==Src0,
// and set the IsDestRedefined flag to keep liveness analysis consistent.
UnimplementedError(getFlags());
}
void TargetMIPS32::makeRandomRegisterPermutation(
llvm::SmallVectorImpl<RegNumT> &Permutation,
const SmallBitVector &ExcludeRegisters, uint64_t Salt) const {
(void)Permutation;
(void)ExcludeRegisters;
(void)Salt;
UnimplementedError(getFlags());
}
/* TODO(jvoung): avoid duplicate symbols with multiple targets.
void ConstantUndef::emitWithoutDollar(GlobalContext *) const {
llvm_unreachable("Not expecting to emitWithoutDollar undef");
}
void ConstantUndef::emit(GlobalContext *) const {
llvm_unreachable("undef value encountered by emitter.");
}
*/
TargetDataMIPS32::TargetDataMIPS32(GlobalContext *Ctx)
: TargetDataLowering(Ctx) {}
void TargetDataMIPS32::lowerGlobals(const VariableDeclarationList &Vars,
const std::string &SectionSuffix) {
const bool IsPIC = getFlags().getUseNonsfi();
switch (getFlags().getOutFileType()) {
case FT_Elf: {
ELFObjectWriter *Writer = Ctx->getObjectWriter();
Writer->writeDataSection(Vars, llvm::ELF::R_MIPS_GLOB_DAT, SectionSuffix,
IsPIC);
} break;
case FT_Asm:
case FT_Iasm: {
OstreamLocker L(Ctx);
for (const VariableDeclaration *Var : Vars) {
if (getFlags().matchTranslateOnly(Var->getName(), 0)) {
emitGlobal(*Var, SectionSuffix);
}
}
} break;
}
}
void TargetDataMIPS32::lowerConstants() {
if (getFlags().getDisableTranslation())
return;
}
void TargetDataMIPS32::lowerJumpTables() {
if (getFlags().getDisableTranslation())
return;
}
// Helper for legalize() to emit the right code to lower an operand to a
// register of the appropriate type.
Variable *TargetMIPS32::copyToReg(Operand *Src, RegNumT RegNum) {
Type Ty = Src->getType();
Variable *Reg = makeReg(Ty, RegNum);
if (isVectorType(Ty)) {
UnimplementedError(getFlags());
} else if (isFloatingType(Ty)) {
(Ty == IceType_f32) ? _mov_s(Reg, llvm::dyn_cast<Variable>(Src))
: _mov_d(Reg, llvm::dyn_cast<Variable>(Src));
} else {
// Mov's Src operand can really only be the flexible second operand type
// or a register. Users should guarantee that.
_mov(Reg, Src);
}
return Reg;
}
Operand *TargetMIPS32::legalize(Operand *From, LegalMask Allowed,
RegNumT RegNum) {
Type Ty = From->getType();
// Assert that a physical register is allowed. To date, all calls
// to legalize() allow a physical register. Legal_Flex converts
// registers to the right type OperandMIPS32FlexReg as needed.
assert(Allowed & Legal_Reg);
// Go through the various types of operands:
// OperandMIPS32Mem, Constant, and Variable.
// Given the above assertion, if type of operand is not legal
// (e.g., OperandMIPS32Mem and !Legal_Mem), we can always copy
// to a register.
if (auto *C = llvm::dyn_cast<ConstantRelocatable>(From)) {
(void)C;
// TODO(reed kotler): complete this case for proper implementation
Variable *Reg = makeReg(Ty, RegNum);
Context.insert<InstFakeDef>(Reg);
return Reg;
} else if (auto *C32 = llvm::dyn_cast<ConstantInteger32>(From)) {
const uint32_t Value = C32->getValue();
// Check if the immediate will fit in a Flexible second operand,
// if a Flexible second operand is allowed. We need to know the exact
// value, so that rules out relocatable constants.
// Also try the inverse and use MVN if possible.
// Do a movw/movt to a register.
Variable *Reg;
if (RegNum.hasValue())
Reg = getPhysicalRegister(RegNum);
else
Reg = makeReg(Ty, RegNum);
if (isInt<16>(int32_t(Value))) {
Variable *Zero = getPhysicalRegister(RegMIPS32::Reg_ZERO, Ty);
Context.insert<InstFakeDef>(Zero);
_addiu(Reg, Zero, Value);
} else {
uint32_t UpperBits = (Value >> 16) & 0xFFFF;
(void)UpperBits;
uint32_t LowerBits = Value & 0xFFFF;
Variable *TReg = makeReg(Ty, RegNum);
_lui(TReg, UpperBits);
_ori(Reg, TReg, LowerBits);
}
return Reg;
}
if (auto *Var = llvm::dyn_cast<Variable>(From)) {
// Check if the variable is guaranteed a physical register. This
// can happen either when the variable is pre-colored or when it is
// assigned infinite weight.
bool MustHaveRegister = (Var->hasReg() || Var->mustHaveReg());
// We need a new physical register for the operand if:
// Mem is not allowed and Var isn't guaranteed a physical
// register, or
// RegNum is required and Var->getRegNum() doesn't match.
if ((!(Allowed & Legal_Mem) && !MustHaveRegister) ||
(RegNum.hasValue() && RegNum != Var->getRegNum())) {
From = copyToReg(From, RegNum);
}
return From;
}
return From;
}
namespace BoolFolding {
// TODO(sagar.thakur): Add remaining instruction kinds to shouldTrackProducer()
// and isValidConsumer()
bool shouldTrackProducer(const Inst &Instr) {
return Instr.getKind() == Inst::Icmp;
}
bool isValidConsumer(const Inst &Instr) { return Instr.getKind() == Inst::Br; }
} // end of namespace BoolFolding
void TargetMIPS32::ComputationTracker::recordProducers(CfgNode *Node) {
for (Inst &Instr : Node->getInsts()) {
if (Instr.isDeleted())
continue;
// Check whether Instr is a valid producer.
Variable *Dest = Instr.getDest();
if (Dest // only consider instructions with an actual dest var; and
&& Dest->getType() == IceType_i1 // only bool-type dest vars; and
&& BoolFolding::shouldTrackProducer(Instr)) { // white-listed instr.
KnownComputations.emplace(Dest->getIndex(),
ComputationEntry(&Instr, IceType_i1));
}
// Check each src variable against the map.
FOREACH_VAR_IN_INST(Var, Instr) {
SizeT VarNum = Var->getIndex();
auto ComputationIter = KnownComputations.find(VarNum);
if (ComputationIter == KnownComputations.end()) {
continue;
}
++ComputationIter->second.NumUses;
switch (ComputationIter->second.ComputationType) {
default:
KnownComputations.erase(VarNum);
continue;
case IceType_i1:
if (!BoolFolding::isValidConsumer(Instr)) {
KnownComputations.erase(VarNum);
continue;
}
break;
}
if (Instr.isLastUse(Var)) {
ComputationIter->second.IsLiveOut = false;
}
}
}
for (auto Iter = KnownComputations.begin(), End = KnownComputations.end();
Iter != End;) {
// Disable the folding if its dest may be live beyond this block.
if (Iter->second.IsLiveOut || Iter->second.NumUses > 1) {
Iter = KnownComputations.erase(Iter);
continue;
}
// Mark as "dead" rather than outright deleting. This is so that other
// peephole style optimizations during or before lowering have access to
// this instruction in undeleted form. See for example
// tryOptimizedCmpxchgCmpBr().
Iter->second.Instr->setDead();
++Iter;
}
}
TargetHeaderMIPS32::TargetHeaderMIPS32(GlobalContext *Ctx)
: TargetHeaderLowering(Ctx) {}
void TargetHeaderMIPS32::lower() {
OstreamLocker L(Ctx);
Ostream &Str = Ctx->getStrEmit();
Str << "\t.set\t"
<< "nomicromips\n";
Str << "\t.set\t"
<< "nomips16\n";
}
SmallBitVector TargetMIPS32::TypeToRegisterSet[RCMIPS32_NUM];
SmallBitVector TargetMIPS32::TypeToRegisterSetUnfiltered[RCMIPS32_NUM];
SmallBitVector TargetMIPS32::RegisterAliases[RegMIPS32::Reg_NUM];
} // end of namespace MIPS32
} // end of namespace Ice