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llvm-project/llvm/lib/Target/Sparc/SparcInstrSelection.cpp

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//===-- SparcInstrSelection.cpp -------------------------------------------===//
//
// BURS instruction selection for SPARC V9 architecture.
//
//===----------------------------------------------------------------------===//
#include "SparcInternals.h"
#include "SparcInstrSelectionSupport.h"
#include "SparcRegClassInfo.h"
#include "llvm/CodeGen/InstrSelectionSupport.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrAnnot.h"
#include "llvm/CodeGen/InstrForest.h"
#include "llvm/CodeGen/InstrSelection.h"
#include "llvm/CodeGen/MachineCodeForMethod.h"
#include "llvm/CodeGen/MachineCodeForInstruction.h"
#include "llvm/DerivedTypes.h"
#include "llvm/iTerminators.h"
#include "llvm/iMemory.h"
#include "llvm/iOther.h"
#include "llvm/Function.h"
#include "llvm/Constants.h"
#include "Support/MathExtras.h"
#include <math.h>
using std::vector;
//************************ Internal Functions ******************************/
static inline MachineOpCode
ChooseBprInstruction(const InstructionNode* instrNode)
{
MachineOpCode opCode;
Instruction* setCCInstr =
((InstructionNode*) instrNode->leftChild())->getInstruction();
switch(setCCInstr->getOpcode())
{
case Instruction::SetEQ: opCode = BRZ; break;
case Instruction::SetNE: opCode = BRNZ; break;
case Instruction::SetLE: opCode = BRLEZ; break;
case Instruction::SetGE: opCode = BRGEZ; break;
case Instruction::SetLT: opCode = BRLZ; break;
case Instruction::SetGT: opCode = BRGZ; break;
default:
assert(0 && "Unrecognized VM instruction!");
opCode = INVALID_OPCODE;
break;
}
return opCode;
}
static inline MachineOpCode
ChooseBpccInstruction(const InstructionNode* instrNode,
const BinaryOperator* setCCInstr)
{
MachineOpCode opCode = INVALID_OPCODE;
bool isSigned = setCCInstr->getOperand(0)->getType()->isSigned();
if (isSigned)
{
switch(setCCInstr->getOpcode())
{
case Instruction::SetEQ: opCode = BE; break;
case Instruction::SetNE: opCode = BNE; break;
case Instruction::SetLE: opCode = BLE; break;
case Instruction::SetGE: opCode = BGE; break;
case Instruction::SetLT: opCode = BL; break;
case Instruction::SetGT: opCode = BG; break;
default:
assert(0 && "Unrecognized VM instruction!");
break;
}
}
else
{
switch(setCCInstr->getOpcode())
{
case Instruction::SetEQ: opCode = BE; break;
case Instruction::SetNE: opCode = BNE; break;
case Instruction::SetLE: opCode = BLEU; break;
case Instruction::SetGE: opCode = BCC; break;
case Instruction::SetLT: opCode = BCS; break;
case Instruction::SetGT: opCode = BGU; break;
default:
assert(0 && "Unrecognized VM instruction!");
break;
}
}
return opCode;
}
static inline MachineOpCode
ChooseBFpccInstruction(const InstructionNode* instrNode,
const BinaryOperator* setCCInstr)
{
MachineOpCode opCode = INVALID_OPCODE;
switch(setCCInstr->getOpcode())
{
case Instruction::SetEQ: opCode = FBE; break;
case Instruction::SetNE: opCode = FBNE; break;
case Instruction::SetLE: opCode = FBLE; break;
case Instruction::SetGE: opCode = FBGE; break;
case Instruction::SetLT: opCode = FBL; break;
case Instruction::SetGT: opCode = FBG; break;
default:
assert(0 && "Unrecognized VM instruction!");
break;
}
return opCode;
}
// Create a unique TmpInstruction for a boolean value,
// representing the CC register used by a branch on that value.
// For now, hack this using a little static cache of TmpInstructions.
// Eventually the entire BURG instruction selection should be put
// into a separate class that can hold such information.
// The static cache is not too bad because the memory for these
// TmpInstructions will be freed along with the rest of the Function anyway.
//
static TmpInstruction*
GetTmpForCC(Value* boolVal, const Function *F, const Type* ccType)
{
typedef hash_map<const Value*, TmpInstruction*> BoolTmpCache;
static BoolTmpCache boolToTmpCache; // Map boolVal -> TmpInstruction*
static const Function *lastFunction = 0;// Use to flush cache between funcs
assert(boolVal->getType() == Type::BoolTy && "Weird but ok! Delete assert");
if (lastFunction != F)
{
lastFunction = F;
boolToTmpCache.clear();
}
// Look for tmpI and create a new one otherwise. The new value is
// directly written to map using the ref returned by operator[].
TmpInstruction*& tmpI = boolToTmpCache[boolVal];
if (tmpI == NULL)
tmpI = new TmpInstruction(ccType, boolVal);
return tmpI;
}
static inline MachineOpCode
ChooseBccInstruction(const InstructionNode* instrNode,
bool& isFPBranch)
{
InstructionNode* setCCNode = (InstructionNode*) instrNode->leftChild();
assert(setCCNode->getOpLabel() == SetCCOp);
BinaryOperator* setCCInstr =cast<BinaryOperator>(setCCNode->getInstruction());
const Type* setCCType = setCCInstr->getOperand(0)->getType();
isFPBranch = setCCType->isFloatingPoint(); // Return value: don't delete!
if (isFPBranch)
return ChooseBFpccInstruction(instrNode, setCCInstr);
else
return ChooseBpccInstruction(instrNode, setCCInstr);
}
static inline MachineOpCode
ChooseMovFpccInstruction(const InstructionNode* instrNode)
{
MachineOpCode opCode = INVALID_OPCODE;
switch(instrNode->getInstruction()->getOpcode())
{
case Instruction::SetEQ: opCode = MOVFE; break;
case Instruction::SetNE: opCode = MOVFNE; break;
case Instruction::SetLE: opCode = MOVFLE; break;
case Instruction::SetGE: opCode = MOVFGE; break;
case Instruction::SetLT: opCode = MOVFL; break;
case Instruction::SetGT: opCode = MOVFG; break;
default:
assert(0 && "Unrecognized VM instruction!");
break;
}
return opCode;
}
// Assumes that SUBcc v1, v2 -> v3 has been executed.
// In most cases, we want to clear v3 and then follow it by instruction
// MOVcc 1 -> v3.
// Set mustClearReg=false if v3 need not be cleared before conditional move.
// Set valueToMove=0 if we want to conditionally move 0 instead of 1
// (i.e., we want to test inverse of a condition)
// (The latter two cases do not seem to arise because SetNE needs nothing.)
//
static MachineOpCode
ChooseMovpccAfterSub(const InstructionNode* instrNode,
bool& mustClearReg,
int& valueToMove)
{
MachineOpCode opCode = INVALID_OPCODE;
mustClearReg = true;
valueToMove = 1;
switch(instrNode->getInstruction()->getOpcode())
{
case Instruction::SetEQ: opCode = MOVE; break;
case Instruction::SetLE: opCode = MOVLE; break;
case Instruction::SetGE: opCode = MOVGE; break;
case Instruction::SetLT: opCode = MOVL; break;
case Instruction::SetGT: opCode = MOVG; break;
case Instruction::SetNE: assert(0 && "No move required!"); break;
default: assert(0 && "Unrecognized VM instr!"); break;
}
return opCode;
}
static inline MachineOpCode
ChooseConvertToFloatInstr(OpLabel vopCode, const Type* opType)
{
MachineOpCode opCode = INVALID_OPCODE;
switch(vopCode)
{
case ToFloatTy:
if (opType == Type::SByteTy || opType == Type::ShortTy || opType == Type::IntTy)
opCode = FITOS;
else if (opType == Type::LongTy)
opCode = FXTOS;
else if (opType == Type::DoubleTy)
opCode = FDTOS;
else if (opType == Type::FloatTy)
;
else
assert(0 && "Cannot convert this type to FLOAT on SPARC");
break;
case ToDoubleTy:
// This is usually used in conjunction with CreateCodeToCopyIntToFloat().
// Both functions should treat the integer as a 32-bit value for types
// of 4 bytes or less, and as a 64-bit value otherwise.
if (opType == Type::SByteTy || opType == Type::UByteTy ||
opType == Type::ShortTy || opType == Type::UShortTy ||
opType == Type::IntTy || opType == Type::UIntTy)
opCode = FITOD;
else if (opType == Type::LongTy || opType == Type::ULongTy)
opCode = FXTOD;
else if (opType == Type::FloatTy)
opCode = FSTOD;
else if (opType == Type::DoubleTy)
;
else
assert(0 && "Cannot convert this type to DOUBLE on SPARC");
break;
default:
break;
}
return opCode;
}
static inline MachineOpCode
ChooseConvertToIntInstr(Type::PrimitiveID tid, const Type* opType)
{
MachineOpCode opCode = INVALID_OPCODE;;
if (tid==Type::SByteTyID || tid==Type::ShortTyID || tid==Type::IntTyID ||
tid==Type::UByteTyID || tid==Type::UShortTyID || tid==Type::UIntTyID)
{
switch (opType->getPrimitiveID())
{
case Type::FloatTyID: opCode = FSTOI; break;
case Type::DoubleTyID: opCode = FDTOI; break;
default:
assert(0 && "Non-numeric non-bool type cannot be converted to Int");
break;
}
}
else if (tid==Type::LongTyID || tid==Type::ULongTyID)
{
switch (opType->getPrimitiveID())
{
case Type::FloatTyID: opCode = FSTOX; break;
case Type::DoubleTyID: opCode = FDTOX; break;
default:
assert(0 && "Non-numeric non-bool type cannot be converted to Long");
break;
}
}
else
assert(0 && "Should not get here, Mo!");
return opCode;
}
MachineInstr*
CreateConvertToIntInstr(Type::PrimitiveID destTID, Value* srcVal,Value* destVal)
{
MachineOpCode opCode = ChooseConvertToIntInstr(destTID, srcVal->getType());
assert(opCode != INVALID_OPCODE && "Expected to need conversion!");
MachineInstr* M = new MachineInstr(opCode);
M->SetMachineOperandVal(0, MachineOperand::MO_VirtualRegister, srcVal);
M->SetMachineOperandVal(1, MachineOperand::MO_VirtualRegister, destVal);
return M;
}
// CreateCodeToConvertFloatToInt: Convert FP value to signed or unsigned integer
// The FP value must be converted to the dest type in an FP register,
// and the result is then copied from FP to int register via memory.
//
// Since fdtoi converts to signed integers, any FP value V between MAXINT+1
// and MAXUNSIGNED (i.e., 2^31 <= V <= 2^32-1) would be converted incorrectly
// *only* when converting to an unsigned int. (Unsigned byte, short or long
// don't have this problem.)
// For unsigned int, we therefore have to generate the code sequence:
//
// if (V > (float) MAXINT) {
// unsigned result = (unsigned) (V - (float) MAXINT);
// result = result + (unsigned) MAXINT;
// }
// else
// result = (unsigned int) V;
//
static void
CreateCodeToConvertFloatToInt(const TargetMachine& target,
Value* opVal,
Instruction* destI,
std::vector<MachineInstr*>& mvec,
MachineCodeForInstruction& mcfi)
{
// Create a temporary to represent the FP register into which the
// int value will placed after conversion. The type of this temporary
// depends on the type of FP register to use: single-prec for a 32-bit
// int or smaller; double-prec for a 64-bit int.
//
size_t destSize = target.DataLayout.getTypeSize(destI->getType());
const Type* destTypeToUse = (destSize > 4)? Type::DoubleTy : Type::FloatTy;
TmpInstruction* destForCast = new TmpInstruction(destTypeToUse, opVal);
mcfi.addTemp(destForCast);
// Create the fp-to-int conversion code
MachineInstr* M = CreateConvertToIntInstr(destI->getType()->getPrimitiveID(),
opVal, destForCast);
mvec.push_back(M);
// Create the fpreg-to-intreg copy code
target.getInstrInfo().
CreateCodeToCopyFloatToInt(target, destI->getParent()->getParent(),
destForCast, destI, mvec, mcfi);
}
static inline MachineOpCode
ChooseAddInstruction(const InstructionNode* instrNode)
{
return ChooseAddInstructionByType(instrNode->getInstruction()->getType());
}
static inline MachineInstr*
CreateMovFloatInstruction(const InstructionNode* instrNode,
const Type* resultType)
{
MachineInstr* minstr = new MachineInstr((resultType == Type::FloatTy)
? FMOVS : FMOVD);
minstr->SetMachineOperandVal(0, MachineOperand::MO_VirtualRegister,
instrNode->leftChild()->getValue());
minstr->SetMachineOperandVal(1, MachineOperand::MO_VirtualRegister,
instrNode->getValue());
return minstr;
}
static inline MachineInstr*
CreateAddConstInstruction(const InstructionNode* instrNode)
{
MachineInstr* minstr = NULL;
Value* constOp = ((InstrTreeNode*) instrNode->rightChild())->getValue();
assert(isa<Constant>(constOp));
// Cases worth optimizing are:
// (1) Add with 0 for float or double: use an FMOV of appropriate type,
// instead of an FADD (1 vs 3 cycles). There is no integer MOV.
//
if (ConstantFP *FPC = dyn_cast<ConstantFP>(constOp)) {
double dval = FPC->getValue();
if (dval == 0.0)
minstr = CreateMovFloatInstruction(instrNode,
instrNode->getInstruction()->getType());
}
return minstr;
}
static inline MachineOpCode
ChooseSubInstructionByType(const Type* resultType)
{
MachineOpCode opCode = INVALID_OPCODE;
if (resultType->isInteger() || isa<PointerType>(resultType))
{
opCode = SUB;
}
else
switch(resultType->getPrimitiveID())
{
case Type::FloatTyID: opCode = FSUBS; break;
case Type::DoubleTyID: opCode = FSUBD; break;
default: assert(0 && "Invalid type for SUB instruction"); break;
}
return opCode;
}
static inline MachineInstr*
CreateSubConstInstruction(const InstructionNode* instrNode)
{
MachineInstr* minstr = NULL;
Value* constOp = ((InstrTreeNode*) instrNode->rightChild())->getValue();
assert(isa<Constant>(constOp));
// Cases worth optimizing are:
// (1) Sub with 0 for float or double: use an FMOV of appropriate type,
// instead of an FSUB (1 vs 3 cycles). There is no integer MOV.
//
if (ConstantFP *FPC = dyn_cast<ConstantFP>(constOp)) {
double dval = FPC->getValue();
if (dval == 0.0)
minstr = CreateMovFloatInstruction(instrNode,
instrNode->getInstruction()->getType());
}
return minstr;
}
static inline MachineOpCode
ChooseFcmpInstruction(const InstructionNode* instrNode)
{
MachineOpCode opCode = INVALID_OPCODE;
Value* operand = ((InstrTreeNode*) instrNode->leftChild())->getValue();
switch(operand->getType()->getPrimitiveID()) {
case Type::FloatTyID: opCode = FCMPS; break;
case Type::DoubleTyID: opCode = FCMPD; break;
default: assert(0 && "Invalid type for FCMP instruction"); break;
}
return opCode;
}
// Assumes that leftArg and rightArg are both cast instructions.
//
static inline bool
BothFloatToDouble(const InstructionNode* instrNode)
{
InstrTreeNode* leftArg = instrNode->leftChild();
InstrTreeNode* rightArg = instrNode->rightChild();
InstrTreeNode* leftArgArg = leftArg->leftChild();
InstrTreeNode* rightArgArg = rightArg->leftChild();
assert(leftArg->getValue()->getType() == rightArg->getValue()->getType());
// Check if both arguments are floats cast to double
return (leftArg->getValue()->getType() == Type::DoubleTy &&
leftArgArg->getValue()->getType() == Type::FloatTy &&
rightArgArg->getValue()->getType() == Type::FloatTy);
}
static inline MachineOpCode
ChooseMulInstructionByType(const Type* resultType)
{
MachineOpCode opCode = INVALID_OPCODE;
if (resultType->isInteger())
opCode = MULX;
else
switch(resultType->getPrimitiveID())
{
case Type::FloatTyID: opCode = FMULS; break;
case Type::DoubleTyID: opCode = FMULD; break;
default: assert(0 && "Invalid type for MUL instruction"); break;
}
return opCode;
}
static inline MachineInstr*
CreateIntNegInstruction(const TargetMachine& target,
Value* vreg)
{
MachineInstr* minstr = new MachineInstr(SUB);
minstr->SetMachineOperandReg(0, target.getRegInfo().getZeroRegNum());
minstr->SetMachineOperandVal(1, MachineOperand::MO_VirtualRegister, vreg);
minstr->SetMachineOperandVal(2, MachineOperand::MO_VirtualRegister, vreg);
return minstr;
}
// Create instruction sequence for any shift operation.
// SLL or SLLX on an operand smaller than the integer reg. size (64bits)
// requires a second instruction for explicit sign-extension.
// Note that we only have to worry about a sign-bit appearing in the
// most significant bit of the operand after shifting (e.g., bit 32 of
// Int or bit 16 of Short), so we do not have to worry about results
// that are as large as a normal integer register.
//
static inline void
CreateShiftInstructions(const TargetMachine& target,
Function* F,
MachineOpCode shiftOpCode,
Value* argVal1,
Value* optArgVal2, /* Use optArgVal2 if not NULL */
unsigned int optShiftNum, /* else use optShiftNum */
Instruction* destVal,
vector<MachineInstr*>& mvec,
MachineCodeForInstruction& mcfi)
{
assert((optArgVal2 != NULL || optShiftNum <= 64) &&
"Large shift sizes unexpected, but can be handled below: "
"You need to check whether or not it fits in immed field below");
// If this is a logical left shift of a type smaller than the standard
// integer reg. size, we have to extend the sign-bit into upper bits
// of dest, so we need to put the result of the SLL into a temporary.
//
Value* shiftDest = destVal;
const Type* opType = argVal1->getType();
unsigned opSize = target.DataLayout.getTypeSize(argVal1->getType());
if ((shiftOpCode == SLL || shiftOpCode == SLLX)
&& opSize < target.DataLayout.getIntegerRegize())
{ // put SLL result into a temporary
shiftDest = new TmpInstruction(argVal1, optArgVal2, "sllTmp");
mcfi.addTemp(shiftDest);
}
MachineInstr* M = (optArgVal2 != NULL)
? Create3OperandInstr(shiftOpCode, argVal1, optArgVal2, shiftDest)
: Create3OperandInstr_UImmed(shiftOpCode, argVal1, optShiftNum, shiftDest);
mvec.push_back(M);
if (shiftDest != destVal)
{ // extend the sign-bit of the result into all upper bits of dest
assert(8*opSize <= 32 && "Unexpected type size > 4 and < IntRegSize?");
target.getInstrInfo().
CreateSignExtensionInstructions(target, F, shiftDest, 8*opSize,
destVal, mvec, mcfi);
}
}
// Does not create any instructions if we cannot exploit constant to
// create a cheaper instruction.
// This returns the approximate cost of the instructions generated,
// which is used to pick the cheapest when both operands are constant.
static inline unsigned int
CreateMulConstInstruction(const TargetMachine &target, Function* F,
Value* lval, Value* rval, Instruction* destVal,
vector<MachineInstr*>& mvec,
MachineCodeForInstruction& mcfi)
{
/* Use max. multiply cost, viz., cost of MULX */
unsigned int cost = target.getInstrInfo().minLatency(MULX);
unsigned int firstNewInstr = mvec.size();
Value* constOp = rval;
if (! isa<Constant>(constOp))
return cost;
// Cases worth optimizing are:
// (1) Multiply by 0 or 1 for any type: replace with copy (ADD or FMOV)
// (2) Multiply by 2^x for integer types: replace with Shift
//
const Type* resultType = destVal->getType();
if (resultType->isInteger() || isa<PointerType>(resultType))
{
bool isValidConst;
int64_t C = GetConstantValueAsSignedInt(constOp, isValidConst);
if (isValidConst)
{
unsigned pow;
bool needNeg = false;
if (C < 0)
{
needNeg = true;
C = -C;
}
if (C == 0 || C == 1)
{
cost = target.getInstrInfo().minLatency(ADD);
MachineInstr* M = (C == 0)
? Create3OperandInstr_Reg(ADD,
target.getRegInfo().getZeroRegNum(),
target.getRegInfo().getZeroRegNum(),
destVal)
: Create3OperandInstr_Reg(ADD, lval,
target.getRegInfo().getZeroRegNum(),
destVal);
mvec.push_back(M);
}
else if (isPowerOf2(C, pow))
{
unsigned int opSize = target.DataLayout.getTypeSize(resultType);
MachineOpCode opCode = (opSize <= 32)? SLL : SLLX;
CreateShiftInstructions(target, F, opCode, lval, NULL, pow,
destVal, mvec, mcfi);
}
if (mvec.size() > 0 && needNeg)
{ // insert <reg = SUB 0, reg> after the instr to flip the sign
MachineInstr* M = CreateIntNegInstruction(target, destVal);
mvec.push_back(M);
}
}
}
else
{
if (ConstantFP *FPC = dyn_cast<ConstantFP>(constOp))
{
double dval = FPC->getValue();
if (fabs(dval) == 1)
{
MachineOpCode opCode = (dval < 0)
? (resultType == Type::FloatTy? FNEGS : FNEGD)
: (resultType == Type::FloatTy? FMOVS : FMOVD);
MachineInstr* M = Create2OperandInstr(opCode, lval, destVal);
mvec.push_back(M);
}
}
}
if (firstNewInstr < mvec.size())
{
cost = 0;
for (unsigned int i=firstNewInstr; i < mvec.size(); ++i)
cost += target.getInstrInfo().minLatency(mvec[i]->getOpCode());
}
return cost;
}
// Does not create any instructions if we cannot exploit constant to
// create a cheaper instruction.
//
static inline void
CreateCheapestMulConstInstruction(const TargetMachine &target,
Function* F,
Value* lval, Value* rval,
Instruction* destVal,
vector<MachineInstr*>& mvec,
MachineCodeForInstruction& mcfi)
{
Value* constOp;
if (isa<Constant>(lval) && isa<Constant>(rval))
{ // both operands are constant: try both orders!
vector<MachineInstr*> mvec1, mvec2;
unsigned int lcost = CreateMulConstInstruction(target, F, lval, rval,
destVal, mvec1, mcfi);
unsigned int rcost = CreateMulConstInstruction(target, F, rval, lval,
destVal, mvec2, mcfi);
vector<MachineInstr*>& mincostMvec = (lcost <= rcost)? mvec1 : mvec2;
vector<MachineInstr*>& maxcostMvec = (lcost <= rcost)? mvec2 : mvec1;
mvec.insert(mvec.end(), mincostMvec.begin(), mincostMvec.end());
for (unsigned int i=0; i < maxcostMvec.size(); ++i)
delete maxcostMvec[i];
}
else if (isa<Constant>(rval)) // rval is constant, but not lval
CreateMulConstInstruction(target, F, lval, rval, destVal, mvec, mcfi);
else if (isa<Constant>(lval)) // lval is constant, but not rval
CreateMulConstInstruction(target, F, lval, rval, destVal, mvec, mcfi);
// else neither is constant
return;
}
// Return NULL if we cannot exploit constant to create a cheaper instruction
static inline void
CreateMulInstruction(const TargetMachine &target, Function* F,
Value* lval, Value* rval, Instruction* destVal,
vector<MachineInstr*>& mvec,
MachineCodeForInstruction& mcfi,
MachineOpCode forceMulOp = INVALID_MACHINE_OPCODE)
{
unsigned int L = mvec.size();
CreateCheapestMulConstInstruction(target,F, lval, rval, destVal, mvec, mcfi);
if (mvec.size() == L)
{ // no instructions were added so create MUL reg, reg, reg.
// Use FSMULD if both operands are actually floats cast to doubles.
// Otherwise, use the default opcode for the appropriate type.
MachineOpCode mulOp = ((forceMulOp != INVALID_MACHINE_OPCODE)
? forceMulOp
: ChooseMulInstructionByType(destVal->getType()));
MachineInstr* M = new MachineInstr(mulOp);
M->SetMachineOperandVal(0, MachineOperand::MO_VirtualRegister, lval);
M->SetMachineOperandVal(1, MachineOperand::MO_VirtualRegister, rval);
M->SetMachineOperandVal(2, MachineOperand::MO_VirtualRegister, destVal);
mvec.push_back(M);
}
}
// Generate a divide instruction for Div or Rem.
// For Rem, this assumes that the operand type will be signed if the result
// type is signed. This is correct because they must have the same sign.
//
static inline MachineOpCode
ChooseDivInstruction(TargetMachine &target,
const InstructionNode* instrNode)
{
MachineOpCode opCode = INVALID_OPCODE;
const Type* resultType = instrNode->getInstruction()->getType();
if (resultType->isInteger())
opCode = resultType->isSigned()? SDIVX : UDIVX;
else
switch(resultType->getPrimitiveID())
{
case Type::FloatTyID: opCode = FDIVS; break;
case Type::DoubleTyID: opCode = FDIVD; break;
default: assert(0 && "Invalid type for DIV instruction"); break;
}
return opCode;
}
// Return NULL if we cannot exploit constant to create a cheaper instruction
static inline void
CreateDivConstInstruction(TargetMachine &target,
const InstructionNode* instrNode,
vector<MachineInstr*>& mvec)
{
MachineInstr* minstr1 = NULL;
MachineInstr* minstr2 = NULL;
Value* constOp = ((InstrTreeNode*) instrNode->rightChild())->getValue();
if (! isa<Constant>(constOp))
return;
// Cases worth optimizing are:
// (1) Divide by 1 for any type: replace with copy (ADD or FMOV)
// (2) Divide by 2^x for integer types: replace with SR[L or A]{X}
//
const Type* resultType = instrNode->getInstruction()->getType();
if (resultType->isInteger())
{
unsigned pow;
bool isValidConst;
int64_t C = GetConstantValueAsSignedInt(constOp, isValidConst);
if (isValidConst)
{
bool needNeg = false;
if (C < 0)
{
needNeg = true;
C = -C;
}
if (C == 1)
{
minstr1 = new MachineInstr(ADD);
minstr1->SetMachineOperandVal(0,
MachineOperand::MO_VirtualRegister,
instrNode->leftChild()->getValue());
minstr1->SetMachineOperandReg(1,
target.getRegInfo().getZeroRegNum());
}
else if (isPowerOf2(C, pow))
{
MachineOpCode opCode= ((resultType->isSigned())
? (resultType==Type::LongTy)? SRAX : SRA
: (resultType==Type::LongTy)? SRLX : SRL);
minstr1 = new MachineInstr(opCode);
minstr1->SetMachineOperandVal(0,
MachineOperand::MO_VirtualRegister,
instrNode->leftChild()->getValue());
minstr1->SetMachineOperandConst(1,
MachineOperand::MO_UnextendedImmed,
pow);
}
if (minstr1 && needNeg)
{ // insert <reg = SUB 0, reg> after the instr to flip the sign
minstr2 = CreateIntNegInstruction(target,
instrNode->getValue());
}
}
}
else
{
if (ConstantFP *FPC = dyn_cast<ConstantFP>(constOp))
{
double dval = FPC->getValue();
if (fabs(dval) == 1)
{
bool needNeg = (dval < 0);
MachineOpCode opCode = needNeg
? (resultType == Type::FloatTy? FNEGS : FNEGD)
: (resultType == Type::FloatTy? FMOVS : FMOVD);
minstr1 = new MachineInstr(opCode);
minstr1->SetMachineOperandVal(0,
MachineOperand::MO_VirtualRegister,
instrNode->leftChild()->getValue());
}
}
}
if (minstr1 != NULL)
minstr1->SetMachineOperandVal(2, MachineOperand::MO_VirtualRegister,
instrNode->getValue());
if (minstr1)
mvec.push_back(minstr1);
if (minstr2)
mvec.push_back(minstr2);
}
static void
CreateCodeForVariableSizeAlloca(const TargetMachine& target,
Instruction* result,
unsigned int tsize,
Value* numElementsVal,
vector<MachineInstr*>& getMvec)
{
MachineInstr* M;
// Create a Value to hold the (constant) element size
Value* tsizeVal = ConstantSInt::get(Type::IntTy, tsize);
// Get the constant offset from SP for dynamically allocated storage
// and create a temporary Value to hold it.
assert(result && result->getParent() && "Result value is not part of a fn?");
Function *F = result->getParent()->getParent();
MachineCodeForMethod& mcInfo = MachineCodeForMethod::get(F);
bool growUp;
ConstantSInt* dynamicAreaOffset =
ConstantSInt::get(Type::IntTy,
target.getFrameInfo().getDynamicAreaOffset(mcInfo,growUp));
assert(! growUp && "Has SPARC v9 stack frame convention changed?");
// Create a temporary value to hold the result of MUL
TmpInstruction* tmpProd = new TmpInstruction(numElementsVal, tsizeVal);
MachineCodeForInstruction::get(result).addTemp(tmpProd);
// Instruction 1: mul numElements, typeSize -> tmpProd
M = new MachineInstr(MULX);
M->SetMachineOperandVal(0, MachineOperand::MO_VirtualRegister, numElementsVal);
M->SetMachineOperandVal(1, MachineOperand::MO_VirtualRegister, tsizeVal);
M->SetMachineOperandVal(2, MachineOperand::MO_VirtualRegister, tmpProd);
getMvec.push_back(M);
// Instruction 2: sub %sp, tmpProd -> %sp
M = new MachineInstr(SUB);
M->SetMachineOperandReg(0, target.getRegInfo().getStackPointer());
M->SetMachineOperandVal(1, MachineOperand::MO_VirtualRegister, tmpProd);
M->SetMachineOperandReg(2, target.getRegInfo().getStackPointer());
getMvec.push_back(M);
// Instruction 3: add %sp, frameSizeBelowDynamicArea -> result
M = new MachineInstr(ADD);
M->SetMachineOperandReg(0, target.getRegInfo().getStackPointer());
M->SetMachineOperandVal(1, MachineOperand::MO_VirtualRegister, dynamicAreaOffset);
M->SetMachineOperandVal(2, MachineOperand::MO_VirtualRegister, result);
getMvec.push_back(M);
}
static void
CreateCodeForFixedSizeAlloca(const TargetMachine& target,
Instruction* result,
unsigned int tsize,
unsigned int numElements,
vector<MachineInstr*>& getMvec)
{
assert(result && result->getParent() &&
"Result value is not part of a function?");
Function *F = result->getParent()->getParent();
MachineCodeForMethod &mcInfo = MachineCodeForMethod::get(F);
// Check if the offset would small enough to use as an immediate in
// load/stores (check LDX because all load/stores have the same-size immediate
// field). If not, put the variable in the dynamically sized area of the
// frame.
unsigned int paddedSizeIgnored;
int offsetFromFP = mcInfo.computeOffsetforLocalVar(target, result,
paddedSizeIgnored,
tsize * numElements);
if (! target.getInstrInfo().constantFitsInImmedField(LDX, offsetFromFP))
{
CreateCodeForVariableSizeAlloca(target, result, tsize,
ConstantSInt::get(Type::IntTy,numElements),
getMvec);
return;
}
// else offset fits in immediate field so go ahead and allocate it.
offsetFromFP = mcInfo.allocateLocalVar(target, result, tsize * numElements);
// Create a temporary Value to hold the constant offset.
// This is needed because it may not fit in the immediate field.
ConstantSInt* offsetVal = ConstantSInt::get(Type::IntTy, offsetFromFP);
// Instruction 1: add %fp, offsetFromFP -> result
MachineInstr* M = new MachineInstr(ADD);
M->SetMachineOperandReg(0, target.getRegInfo().getFramePointer());
M->SetMachineOperandVal(1, MachineOperand::MO_VirtualRegister, offsetVal);
M->SetMachineOperandVal(2, MachineOperand::MO_VirtualRegister, result);
getMvec.push_back(M);
}
//------------------------------------------------------------------------
// Function SetOperandsForMemInstr
//
// Choose addressing mode for the given load or store instruction.
// Use [reg+reg] if it is an indexed reference, and the index offset is
// not a constant or if it cannot fit in the offset field.
// Use [reg+offset] in all other cases.
//
// This assumes that all array refs are "lowered" to one of these forms:
// %x = load (subarray*) ptr, constant ; single constant offset
// %x = load (subarray*) ptr, offsetVal ; single non-constant offset
// Generally, this should happen via strength reduction + LICM.
// Also, strength reduction should take care of using the same register for
// the loop index variable and an array index, when that is profitable.
//------------------------------------------------------------------------
static void
SetOperandsForMemInstr(vector<MachineInstr*>& mvec,
const InstructionNode* vmInstrNode,
const TargetMachine& target)
{
Instruction* memInst = vmInstrNode->getInstruction();
vector<MachineInstr*>::iterator mvecI = mvec.end() - 1;
// Index vector, ptr value, and flag if all indices are const.
vector<Value*> idxVec;
bool allConstantIndices;
Value* ptrVal = GetMemInstArgs(vmInstrNode, idxVec, allConstantIndices);
// Now create the appropriate operands for the machine instruction.
// First, initialize so we default to storing the offset in a register.
int64_t smallConstOffset = 0;
Value* valueForRegOffset = NULL;
MachineOperand::MachineOperandType offsetOpType =
MachineOperand::MO_VirtualRegister;
// Check if there is an index vector and if so, compute the
// right offset for structures and for arrays
//
if (!idxVec.empty())
{
const PointerType* ptrType = cast<PointerType>(ptrVal->getType());
// If all indices are constant, compute the combined offset directly.
if (allConstantIndices)
{
// Compute the offset value using the index vector. Create a
// virtual reg. for it since it may not fit in the immed field.
uint64_t offset = target.DataLayout.getIndexedOffset(ptrType,idxVec);
valueForRegOffset = ConstantSInt::get(Type::LongTy, offset);
}
else
{
// There is at least one non-constant offset. Therefore, this must
// be an array ref, and must have been lowered to a single non-zero
// offset. (An extra leading zero offset, if any, can be ignored.)
// Generate code sequence to compute address from index.
//
bool firstIdxIsZero =
(idxVec[0] == Constant::getNullValue(idxVec[0]->getType()));
assert(idxVec.size() == 1U + firstIdxIsZero
&& "Array refs must be lowered before Instruction Selection");
Value* idxVal = idxVec[firstIdxIsZero];
assert(! isa<Constant>(idxVal) && "Need to sign-extend uint to 64b!");
vector<MachineInstr*> mulVec;
Instruction* addr = new TmpInstruction(Type::UIntTy, memInst);
MachineCodeForInstruction::get(memInst).addTemp(addr);
// Get the array type indexed by idxVal, and compute its element size.
// The call to getTypeSize() will fail if size is not constant.
const Type* vecType = (firstIdxIsZero
? GetElementPtrInst::getIndexedType(ptrType,
std::vector<Value*>(1U, idxVec[0]),
/*AllowCompositeLeaf*/ true)
: ptrType);
const Type* eltType = cast<SequentialType>(vecType)->getElementType();
ConstantUInt* eltSizeVal = ConstantUInt::get(Type::UIntTy,
target.DataLayout.getTypeSize(eltType));
// CreateMulInstruction() folds constants intelligently enough.
CreateMulInstruction(target,
memInst->getParent()->getParent(),
idxVal, /* lval, not likely to be const*/
eltSizeVal, /* rval, likely to be constant */
addr, /* result */
mulVec,
MachineCodeForInstruction::get(memInst),
INVALID_MACHINE_OPCODE);
// Sign-extend the result of MUL from 32 to 64 bits.
target.getInstrInfo().CreateSignExtensionInstructions(target, memInst->getParent()->getParent(), addr, /*srcSizeInBits*/32, addr, mulVec, MachineCodeForInstruction::get(memInst));
// Insert mulVec[] before *mvecI in mvec[] and update mvecI
// to point to the same instruction it pointed to before.
assert(mulVec.size() > 0 && "No multiply code created?");
vector<MachineInstr*>::iterator oldMvecI = mvecI;
for (unsigned i=0, N=mulVec.size(); i < N; ++i)
mvecI = mvec.insert(mvecI, mulVec[i]) + 1; // pts to mem instr
valueForRegOffset = addr;
}
}
else
{
offsetOpType = MachineOperand::MO_SignExtendedImmed;
smallConstOffset = 0;
}
// For STORE:
// Operand 0 is value, operand 1 is ptr, operand 2 is offset
// For LOAD or GET_ELEMENT_PTR,
// Operand 0 is ptr, operand 1 is offset, operand 2 is result.
//
unsigned offsetOpNum, ptrOpNum;
if (memInst->getOpcode() == Instruction::Store)
{
(*mvecI)->SetMachineOperandVal(0, MachineOperand::MO_VirtualRegister,
vmInstrNode->leftChild()->getValue());
ptrOpNum = 1;
offsetOpNum = 2;
}
else
{
ptrOpNum = 0;
offsetOpNum = 1;
(*mvecI)->SetMachineOperandVal(2, MachineOperand::MO_VirtualRegister,
memInst);
}
(*mvecI)->SetMachineOperandVal(ptrOpNum, MachineOperand::MO_VirtualRegister,
ptrVal);
if (offsetOpType == MachineOperand::MO_VirtualRegister)
{
assert(valueForRegOffset != NULL);
(*mvecI)->SetMachineOperandVal(offsetOpNum, offsetOpType,
valueForRegOffset);
}
else
(*mvecI)->SetMachineOperandConst(offsetOpNum, offsetOpType,
smallConstOffset);
}
//
// Substitute operand `operandNum' of the instruction in node `treeNode'
// in place of the use(s) of that instruction in node `parent'.
// Check both explicit and implicit operands!
// Also make sure to skip over a parent who:
// (1) is a list node in the Burg tree, or
// (2) itself had its results forwarded to its parent
//
static void
ForwardOperand(InstructionNode* treeNode,
InstrTreeNode* parent,
int operandNum)
{
assert(treeNode && parent && "Invalid invocation of ForwardOperand");
Instruction* unusedOp = treeNode->getInstruction();
Value* fwdOp = unusedOp->getOperand(operandNum);
// The parent itself may be a list node, so find the real parent instruction
while (parent->getNodeType() != InstrTreeNode::NTInstructionNode)
{
parent = parent->parent();
assert(parent && "ERROR: Non-instruction node has no parent in tree.");
}
InstructionNode* parentInstrNode = (InstructionNode*) parent;
Instruction* userInstr = parentInstrNode->getInstruction();
MachineCodeForInstruction &mvec = MachineCodeForInstruction::get(userInstr);
// The parent's mvec would be empty if it was itself forwarded.
// Recursively call ForwardOperand in that case...
//
if (mvec.size() == 0)
{
assert(parent->parent() != NULL &&
"Parent could not have been forwarded, yet has no instructions?");
ForwardOperand(treeNode, parent->parent(), operandNum);
}
else
{
for (unsigned i=0, N=mvec.size(); i < N; i++)
{
MachineInstr* minstr = mvec[i];
for (unsigned i=0, numOps=minstr->getNumOperands(); i < numOps; ++i)
{
const MachineOperand& mop = minstr->getOperand(i);
if (mop.getOperandType() == MachineOperand::MO_VirtualRegister &&
mop.getVRegValue() == unusedOp)
minstr->SetMachineOperandVal(i,
MachineOperand::MO_VirtualRegister, fwdOp);
}
for (unsigned i=0,numOps=minstr->getNumImplicitRefs(); i<numOps; ++i)
if (minstr->getImplicitRef(i) == unusedOp)
minstr->setImplicitRef(i, fwdOp,
minstr->implicitRefIsDefined(i),
minstr->implicitRefIsDefinedAndUsed(i));
}
}
}
inline bool
AllUsesAreBranches(const Instruction* setccI)
{
for (Value::use_const_iterator UI=setccI->use_begin(), UE=setccI->use_end();
UI != UE; ++UI)
if (! isa<TmpInstruction>(*UI) // ignore tmp instructions here
&& cast<Instruction>(*UI)->getOpcode() != Instruction::Br)
return false;
return true;
}
//******************* Externally Visible Functions *************************/
//------------------------------------------------------------------------
// External Function: ThisIsAChainRule
//
// Purpose:
// Check if a given BURG rule is a chain rule.
//------------------------------------------------------------------------
extern bool
ThisIsAChainRule(int eruleno)
{
switch(eruleno)
{
case 111: // stmt: reg
case 123:
case 124:
case 125:
case 126:
case 127:
case 128:
case 129:
case 130:
case 131:
case 132:
case 133:
case 155:
case 221:
case 222:
case 241:
case 242:
case 243:
case 244:
case 245:
case 321:
return true; break;
default:
return false; break;
}
}
//------------------------------------------------------------------------
// External Function: GetInstructionsByRule
//
// Purpose:
// Choose machine instructions for the SPARC according to the
// patterns chosen by the BURG-generated parser.
//------------------------------------------------------------------------
void
GetInstructionsByRule(InstructionNode* subtreeRoot,
int ruleForNode,
short* nts,
TargetMachine &target,
vector<MachineInstr*>& mvec)
{
bool checkCast = false; // initialize here to use fall-through
bool maskUnsignedResult = false;
int nextRule;
int forwardOperandNum = -1;
unsigned int allocaSize = 0;
MachineInstr* M, *M2;
unsigned int L;
mvec.clear();
// If the code for this instruction was folded into the parent (user),
// then do nothing!
if (subtreeRoot->isFoldedIntoParent())
return;
//
// Let's check for chain rules outside the switch so that we don't have
// to duplicate the list of chain rule production numbers here again
//
if (ThisIsAChainRule(ruleForNode))
{
// Chain rules have a single nonterminal on the RHS.
// Get the rule that matches the RHS non-terminal and use that instead.
//
assert(nts[0] && ! nts[1]
&& "A chain rule should have only one RHS non-terminal!");
nextRule = burm_rule(subtreeRoot->state, nts[0]);
nts = burm_nts[nextRule];
GetInstructionsByRule(subtreeRoot, nextRule, nts, target, mvec);
}
else
{
switch(ruleForNode) {
case 1: // stmt: Ret
case 2: // stmt: RetValue(reg)
{ // NOTE: Prepass of register allocation is responsible
// for moving return value to appropriate register.
// Mark the return-address register as a hidden virtual reg.
// Mark the return value register as an implicit ref of
// the machine instruction.
// Finally put a NOP in the delay slot.
ReturnInst *returnInstr =
cast<ReturnInst>(subtreeRoot->getInstruction());
assert(returnInstr->getOpcode() == Instruction::Ret);
Instruction* returnReg = new TmpInstruction(returnInstr);
MachineCodeForInstruction::get(returnInstr).addTemp(returnReg);
M = new MachineInstr(JMPLRET);
M->SetMachineOperandReg(0, MachineOperand::MO_VirtualRegister,
returnReg);
M->SetMachineOperandConst(1,MachineOperand::MO_SignExtendedImmed,
(int64_t)8);
M->SetMachineOperandReg(2, target.getRegInfo().getZeroRegNum());
if (returnInstr->getReturnValue() != NULL)
M->addImplicitRef(returnInstr->getReturnValue());
mvec.push_back(M);
mvec.push_back(new MachineInstr(NOP));
break;
}
case 3: // stmt: Store(reg,reg)
case 4: // stmt: Store(reg,ptrreg)
mvec.push_back(new MachineInstr(
ChooseStoreInstruction(
subtreeRoot->leftChild()->getValue()->getType())));
SetOperandsForMemInstr(mvec, subtreeRoot, target);
break;
case 5: // stmt: BrUncond
M = new MachineInstr(BA);
M->SetMachineOperandVal(0, MachineOperand::MO_PCRelativeDisp,
cast<BranchInst>(subtreeRoot->getInstruction())->getSuccessor(0));
mvec.push_back(M);
// delay slot
mvec.push_back(new MachineInstr(NOP));
break;
case 206: // stmt: BrCond(setCCconst)
{ // setCCconst => boolean was computed with `%b = setCC type reg1 const'
// If the constant is ZERO, we can use the branch-on-integer-register
// instructions and avoid the SUBcc instruction entirely.
// Otherwise this is just the same as case 5, so just fall through.
//
InstrTreeNode* constNode = subtreeRoot->leftChild()->rightChild();
assert(constNode &&
constNode->getNodeType() ==InstrTreeNode::NTConstNode);
Constant *constVal = cast<Constant>(constNode->getValue());
bool isValidConst;
if ((constVal->getType()->isInteger()
|| isa<PointerType>(constVal->getType()))
&& GetConstantValueAsSignedInt(constVal, isValidConst) == 0
&& isValidConst)
{
// That constant is a zero after all...
// Use the left child of setCC as the first argument!
// Mark the setCC node so that no code is generated for it.
InstructionNode* setCCNode = (InstructionNode*)
subtreeRoot->leftChild();
assert(setCCNode->getOpLabel() == SetCCOp);
setCCNode->markFoldedIntoParent();
BranchInst* brInst=cast<BranchInst>(subtreeRoot->getInstruction());
M = new MachineInstr(ChooseBprInstruction(subtreeRoot));
M->SetMachineOperandVal(0, MachineOperand::MO_VirtualRegister,
setCCNode->leftChild()->getValue());
M->SetMachineOperandVal(1, MachineOperand::MO_PCRelativeDisp,
brInst->getSuccessor(0));
mvec.push_back(M);
// delay slot
mvec.push_back(new MachineInstr(NOP));
// false branch
M = new MachineInstr(BA);
M->SetMachineOperandVal(0, MachineOperand::MO_PCRelativeDisp,
brInst->getSuccessor(1));
mvec.push_back(M);
// delay slot
mvec.push_back(new MachineInstr(NOP));
break;
}
// ELSE FALL THROUGH
}
case 6: // stmt: BrCond(setCC)
{ // bool => boolean was computed with SetCC.
// The branch to use depends on whether it is FP, signed, or unsigned.
// If it is an integer CC, we also need to find the unique
// TmpInstruction representing that CC.
//
BranchInst* brInst = cast<BranchInst>(subtreeRoot->getInstruction());
bool isFPBranch;
M = new MachineInstr(ChooseBccInstruction(subtreeRoot, isFPBranch));
Value* ccValue = GetTmpForCC(subtreeRoot->leftChild()->getValue(),
brInst->getParent()->getParent(),
isFPBranch? Type::FloatTy : Type::IntTy);
M->SetMachineOperandVal(0, MachineOperand::MO_CCRegister, ccValue);
M->SetMachineOperandVal(1, MachineOperand::MO_PCRelativeDisp,
brInst->getSuccessor(0));
mvec.push_back(M);
// delay slot
mvec.push_back(new MachineInstr(NOP));
// false branch
M = new MachineInstr(BA);
M->SetMachineOperandVal(0, MachineOperand::MO_PCRelativeDisp,
brInst->getSuccessor(1));
mvec.push_back(M);
// delay slot
mvec.push_back(new MachineInstr(NOP));
break;
}
case 208: // stmt: BrCond(boolconst)
{
// boolconst => boolean is a constant; use BA to first or second label
Constant* constVal =
cast<Constant>(subtreeRoot->leftChild()->getValue());
unsigned dest = cast<ConstantBool>(constVal)->getValue()? 0 : 1;
M = new MachineInstr(BA);
M->SetMachineOperandVal(0, MachineOperand::MO_PCRelativeDisp,
cast<BranchInst>(subtreeRoot->getInstruction())->getSuccessor(dest));
mvec.push_back(M);
// delay slot
mvec.push_back(new MachineInstr(NOP));
break;
}
case 8: // stmt: BrCond(boolreg)
{ // boolreg => boolean is stored in an existing register.
// Just use the branch-on-integer-register instruction!
//
M = new MachineInstr(BRNZ);
M->SetMachineOperandVal(0, MachineOperand::MO_VirtualRegister,
subtreeRoot->leftChild()->getValue());
M->SetMachineOperandVal(1, MachineOperand::MO_PCRelativeDisp,
cast<BranchInst>(subtreeRoot->getInstruction())->getSuccessor(0));
mvec.push_back(M);
// delay slot
mvec.push_back(new MachineInstr(NOP));
// false branch
M = new MachineInstr(BA);
M->SetMachineOperandVal(0, MachineOperand::MO_PCRelativeDisp,
cast<BranchInst>(subtreeRoot->getInstruction())->getSuccessor(1));
mvec.push_back(M);
// delay slot
mvec.push_back(new MachineInstr(NOP));
break;
}
case 9: // stmt: Switch(reg)
assert(0 && "*** SWITCH instruction is not implemented yet.");
break;
case 10: // reg: VRegList(reg, reg)
assert(0 && "VRegList should never be the topmost non-chain rule");
break;
case 21: // bool: Not(bool,reg): Both these are implemented as:
case 421: // reg: BNot(reg,reg): reg = reg XOR-NOT 0
{ // First find the unary operand. It may be left or right, usually right.
Value* notArg = BinaryOperator::getNotArgument(
cast<BinaryOperator>(subtreeRoot->getInstruction()));
mvec.push_back(Create3OperandInstr_Reg(XNOR, notArg,
target.getRegInfo().getZeroRegNum(),
subtreeRoot->getValue()));
break;
}
case 22: // reg: ToBoolTy(reg):
{
const Type* opType = subtreeRoot->leftChild()->getValue()->getType();
assert(opType->isIntegral() || isa<PointerType>(opType));
forwardOperandNum = 0; // forward first operand to user
break;
}
case 23: // reg: ToUByteTy(reg)
case 25: // reg: ToUShortTy(reg)
case 27: // reg: ToUIntTy(reg)
case 29: // reg: ToULongTy(reg)
{
Instruction* destI = subtreeRoot->getInstruction();
Value* opVal = subtreeRoot->leftChild()->getValue();
const Type* opType = subtreeRoot->leftChild()->getValue()->getType();
if (opType->isIntegral() || isa<PointerType>(opType))
{
unsigned opSize = target.DataLayout.getTypeSize(opType);
unsigned destSize = target.DataLayout.getTypeSize(destI->getType());
if (opSize > destSize ||
(opType->isSigned()
&& destSize < target.DataLayout.getIntegerRegize()))
{ // operand is larger than dest,
// OR both are equal but smaller than the full register size
// AND operand is signed, so it may have extra sign bits:
// mask high bits using AND
M = Create3OperandInstr(AND, opVal,
ConstantUInt::get(Type::ULongTy,
((uint64_t) 1 << 8*destSize) - 1),
destI);
mvec.push_back(M);
}
else
forwardOperandNum = 0; // forward first operand to user
}
else if (opType->isFloatingPoint())
{
CreateCodeToConvertFloatToInt(target, opVal, destI, mvec,
MachineCodeForInstruction::get(destI));
maskUnsignedResult = true; // not handled by convert code
}
else
assert(0 && "Unrecognized operand type for convert-to-unsigned");
break;
}
case 24: // reg: ToSByteTy(reg)
case 26: // reg: ToShortTy(reg)
case 28: // reg: ToIntTy(reg)
case 30: // reg: ToLongTy(reg)
{
Instruction* destI = subtreeRoot->getInstruction();
Value* opVal = subtreeRoot->leftChild()->getValue();
MachineCodeForInstruction& mcfi =MachineCodeForInstruction::get(destI);
const Type* opType = opVal->getType();
if (opType->isIntegral() || isa<PointerType>(opType))
{
// These operand types have the same format as the destination,
// but may have different size: add sign bits or mask as needed.
//
const Type* destType = destI->getType();
unsigned opSize = target.DataLayout.getTypeSize(opType);
unsigned destSize = target.DataLayout.getTypeSize(destType);
if (opSize < destSize ||
(opSize == destSize &&
opSize == target.DataLayout.getIntegerRegize()))
{ // operand is smaller or both operand and result fill register
forwardOperandNum = 0; // forward first operand to user
}
else
{ // need to mask (possibly) and then sign-extend (definitely)
Value* srcForSignExt = opVal;
unsigned srcSizeForSignExt = 8 * opSize;
if (opSize > destSize)
{ // operand is larger than dest: mask high bits
TmpInstruction *tmpI = new TmpInstruction(destType, opVal,
destI, "maskHi");
mcfi.addTemp(tmpI);
M = Create3OperandInstr(AND, opVal,
ConstantUInt::get(Type::ULongTy,
((uint64_t) 1 << 8*destSize)-1),
tmpI);
mvec.push_back(M);
srcForSignExt = tmpI;
srcSizeForSignExt = 8 * destSize;
}
// sign-extend
target.getInstrInfo().CreateSignExtensionInstructions(target, destI->getParent()->getParent(), srcForSignExt, srcSizeForSignExt, destI, mvec, mcfi);
}
}
else if (opType->isFloatingPoint())
CreateCodeToConvertFloatToInt(target, opVal, destI, mvec, mcfi);
else
assert(0 && "Unrecognized operand type for convert-to-signed");
break;
}
case 31: // reg: ToFloatTy(reg):
case 32: // reg: ToDoubleTy(reg):
case 232: // reg: ToDoubleTy(Constant):
// If this instruction has a parent (a user) in the tree
// and the user is translated as an FsMULd instruction,
// then the cast is unnecessary. So check that first.
// In the future, we'll want to do the same for the FdMULq instruction,
// so do the check here instead of only for ToFloatTy(reg).
//
if (subtreeRoot->parent() != NULL)
{
const MachineCodeForInstruction& mcfi =
MachineCodeForInstruction::get(
cast<InstructionNode>(subtreeRoot->parent())->getInstruction());
if (mcfi.size() == 0 || mcfi.front()->getOpCode() == FSMULD)
forwardOperandNum = 0; // forward first operand to user
}
if (forwardOperandNum != 0) // we do need the cast
{
Value* leftVal = subtreeRoot->leftChild()->getValue();
const Type* opType = leftVal->getType();
MachineOpCode opCode=ChooseConvertToFloatInstr(
subtreeRoot->getOpLabel(), opType);
if (opCode == INVALID_OPCODE) // no conversion needed
{
forwardOperandNum = 0; // forward first operand to user
}
else
{
// If the source operand is a non-FP type it must be
// first copied from int to float register via memory!
Instruction *dest = subtreeRoot->getInstruction();
Value* srcForCast;
int n = 0;
if (! opType->isFloatingPoint())
{
// Create a temporary to represent the FP register
// into which the integer will be copied via memory.
// The type of this temporary will determine the FP
// register used: single-prec for a 32-bit int or smaller,
// double-prec for a 64-bit int.
//
uint64_t srcSize =
target.DataLayout.getTypeSize(leftVal->getType());
Type* tmpTypeToUse =
(srcSize <= 4)? Type::FloatTy : Type::DoubleTy;
srcForCast = new TmpInstruction(tmpTypeToUse, dest);
MachineCodeForInstruction &destMCFI =
MachineCodeForInstruction::get(dest);
destMCFI.addTemp(srcForCast);
target.getInstrInfo().CreateCodeToCopyIntToFloat(target,
dest->getParent()->getParent(),
leftVal, cast<Instruction>(srcForCast),
mvec, destMCFI);
}
else
srcForCast = leftVal;
M = new MachineInstr(opCode);
M->SetMachineOperandVal(0, MachineOperand::MO_VirtualRegister,
srcForCast);
M->SetMachineOperandVal(1, MachineOperand::MO_VirtualRegister,
dest);
mvec.push_back(M);
}
}
break;
case 19: // reg: ToArrayTy(reg):
case 20: // reg: ToPointerTy(reg):
forwardOperandNum = 0; // forward first operand to user
break;
case 233: // reg: Add(reg, Constant)
maskUnsignedResult = true;
M = CreateAddConstInstruction(subtreeRoot);
if (M != NULL)
{
mvec.push_back(M);
break;
}
// ELSE FALL THROUGH
case 33: // reg: Add(reg, reg)
maskUnsignedResult = true;
mvec.push_back(new MachineInstr(ChooseAddInstruction(subtreeRoot)));
Set3OperandsFromInstr(mvec.back(), subtreeRoot, target);
break;
case 234: // reg: Sub(reg, Constant)
maskUnsignedResult = true;
M = CreateSubConstInstruction(subtreeRoot);
if (M != NULL)
{
mvec.push_back(M);
break;
}
// ELSE FALL THROUGH
case 34: // reg: Sub(reg, reg)
maskUnsignedResult = true;
mvec.push_back(new MachineInstr(ChooseSubInstructionByType(
subtreeRoot->getInstruction()->getType())));
Set3OperandsFromInstr(mvec.back(), subtreeRoot, target);
break;
case 135: // reg: Mul(todouble, todouble)
checkCast = true;
// FALL THROUGH
case 35: // reg: Mul(reg, reg)
{
maskUnsignedResult = true;
MachineOpCode forceOp = ((checkCast && BothFloatToDouble(subtreeRoot))
? FSMULD
: INVALID_MACHINE_OPCODE);
Instruction* mulInstr = subtreeRoot->getInstruction();
CreateMulInstruction(target, mulInstr->getParent()->getParent(),
subtreeRoot->leftChild()->getValue(),
subtreeRoot->rightChild()->getValue(),
mulInstr, mvec,
MachineCodeForInstruction::get(mulInstr),forceOp);
break;
}
case 335: // reg: Mul(todouble, todoubleConst)
checkCast = true;
// FALL THROUGH
case 235: // reg: Mul(reg, Constant)
{
maskUnsignedResult = true;
MachineOpCode forceOp = ((checkCast && BothFloatToDouble(subtreeRoot))
? FSMULD
: INVALID_MACHINE_OPCODE);
Instruction* mulInstr = subtreeRoot->getInstruction();
CreateMulInstruction(target, mulInstr->getParent()->getParent(),
subtreeRoot->leftChild()->getValue(),
subtreeRoot->rightChild()->getValue(),
mulInstr, mvec,
MachineCodeForInstruction::get(mulInstr),
forceOp);
break;
}
case 236: // reg: Div(reg, Constant)
maskUnsignedResult = true;
L = mvec.size();
CreateDivConstInstruction(target, subtreeRoot, mvec);
if (mvec.size() > L)
break;
// ELSE FALL THROUGH
case 36: // reg: Div(reg, reg)
maskUnsignedResult = true;
mvec.push_back(new MachineInstr(ChooseDivInstruction(target, subtreeRoot)));
Set3OperandsFromInstr(mvec.back(), subtreeRoot, target);
break;
case 37: // reg: Rem(reg, reg)
case 237: // reg: Rem(reg, Constant)
{
maskUnsignedResult = true;
Instruction* remInstr = subtreeRoot->getInstruction();
TmpInstruction* quot = new TmpInstruction(
subtreeRoot->leftChild()->getValue(),
subtreeRoot->rightChild()->getValue());
TmpInstruction* prod = new TmpInstruction(
quot,
subtreeRoot->rightChild()->getValue());
MachineCodeForInstruction::get(remInstr).addTemp(quot).addTemp(prod);
M = new MachineInstr(ChooseDivInstruction(target, subtreeRoot));
Set3OperandsFromInstr(M, subtreeRoot, target);
M->SetMachineOperandVal(2, MachineOperand::MO_VirtualRegister,quot);
mvec.push_back(M);
M = Create3OperandInstr(ChooseMulInstructionByType(
subtreeRoot->getInstruction()->getType()),
quot, subtreeRoot->rightChild()->getValue(),
prod);
mvec.push_back(M);
M = new MachineInstr(ChooseSubInstructionByType(
subtreeRoot->getInstruction()->getType()));
Set3OperandsFromInstr(M, subtreeRoot, target);
M->SetMachineOperandVal(1, MachineOperand::MO_VirtualRegister,prod);
mvec.push_back(M);
break;
}
case 38: // bool: And(bool, bool)
case 238: // bool: And(bool, boolconst)
case 338: // reg : BAnd(reg, reg)
case 538: // reg : BAnd(reg, Constant)
mvec.push_back(new MachineInstr(AND));
Set3OperandsFromInstr(mvec.back(), subtreeRoot, target);
break;
case 138: // bool: And(bool, not)
case 438: // bool: BAnd(bool, bnot)
{ // Use the argument of NOT as the second argument!
// Mark the NOT node so that no code is generated for it.
InstructionNode* notNode = (InstructionNode*) subtreeRoot->rightChild();
Value* notArg = BinaryOperator::getNotArgument(
cast<BinaryOperator>(notNode->getInstruction()));
notNode->markFoldedIntoParent();
mvec.push_back(Create3OperandInstr(ANDN,
subtreeRoot->leftChild()->getValue(),
notArg, subtreeRoot->getValue()));
break;
}
case 39: // bool: Or(bool, bool)
case 239: // bool: Or(bool, boolconst)
case 339: // reg : BOr(reg, reg)
case 539: // reg : BOr(reg, Constant)
mvec.push_back(new MachineInstr(OR));
Set3OperandsFromInstr(mvec.back(), subtreeRoot, target);
break;
case 139: // bool: Or(bool, not)
case 439: // bool: BOr(bool, bnot)
{ // Use the argument of NOT as the second argument!
// Mark the NOT node so that no code is generated for it.
InstructionNode* notNode = (InstructionNode*) subtreeRoot->rightChild();
Value* notArg = BinaryOperator::getNotArgument(
cast<BinaryOperator>(notNode->getInstruction()));
notNode->markFoldedIntoParent();
mvec.push_back(Create3OperandInstr(ORN,
subtreeRoot->leftChild()->getValue(),
notArg, subtreeRoot->getValue()));
break;
}
case 40: // bool: Xor(bool, bool)
case 240: // bool: Xor(bool, boolconst)
case 340: // reg : BXor(reg, reg)
case 540: // reg : BXor(reg, Constant)
mvec.push_back(new MachineInstr(XOR));
Set3OperandsFromInstr(mvec.back(), subtreeRoot, target);
break;
case 140: // bool: Xor(bool, not)
case 440: // bool: BXor(bool, bnot)
{ // Use the argument of NOT as the second argument!
// Mark the NOT node so that no code is generated for it.
InstructionNode* notNode = (InstructionNode*) subtreeRoot->rightChild();
Value* notArg = BinaryOperator::getNotArgument(
cast<BinaryOperator>(notNode->getInstruction()));
notNode->markFoldedIntoParent();
mvec.push_back(Create3OperandInstr(XNOR,
subtreeRoot->leftChild()->getValue(),
notArg, subtreeRoot->getValue()));
break;
}
case 41: // boolconst: SetCC(reg, Constant)
//
// If the SetCC was folded into the user (parent), it will be
// caught above. All other cases are the same as case 42,
// so just fall through.
//
case 42: // bool: SetCC(reg, reg):
{
// This generates a SUBCC instruction, putting the difference in
// a result register, and setting a condition code.
//
// If the boolean result of the SetCC is used by anything other
// than a branch instruction, or if it is used outside the current
// basic block, the boolean must be
// computed and stored in the result register. Otherwise, discard
// the difference (by using %g0) and keep only the condition code.
//
// To compute the boolean result in a register we use a conditional
// move, unless the result of the SUBCC instruction can be used as
// the bool! This assumes that zero is FALSE and any non-zero
// integer is TRUE.
//
InstructionNode* parentNode = (InstructionNode*) subtreeRoot->parent();
Instruction* setCCInstr = subtreeRoot->getInstruction();
bool keepBoolVal = parentNode == NULL ||
! AllUsesAreBranches(setCCInstr);
bool subValIsBoolVal = setCCInstr->getOpcode() == Instruction::SetNE;
bool keepSubVal = keepBoolVal && subValIsBoolVal;
bool computeBoolVal = keepBoolVal && ! subValIsBoolVal;
bool mustClearReg;
int valueToMove;
MachineOpCode movOpCode = 0;
// Mark the 4th operand as being a CC register, and as a def
// A TmpInstruction is created to represent the CC "result".
// Unlike other instances of TmpInstruction, this one is used
// by machine code of multiple LLVM instructions, viz.,
// the SetCC and the branch. Make sure to get the same one!
// Note that we do this even for FP CC registers even though they
// are explicit operands, because the type of the operand
// needs to be a floating point condition code, not an integer
// condition code. Think of this as casting the bool result to
// a FP condition code register.
//
Value* leftVal = subtreeRoot->leftChild()->getValue();
bool isFPCompare = leftVal->getType()->isFloatingPoint();
TmpInstruction* tmpForCC = GetTmpForCC(setCCInstr,
setCCInstr->getParent()->getParent(),
isFPCompare ? Type::FloatTy : Type::IntTy);
MachineCodeForInstruction::get(setCCInstr).addTemp(tmpForCC);
if (! isFPCompare)
{
// Integer condition: dest. should be %g0 or an integer register.
// If result must be saved but condition is not SetEQ then we need
// a separate instruction to compute the bool result, so discard
// result of SUBcc instruction anyway.
//
M = new MachineInstr(SUBcc);
Set3OperandsFromInstr(M, subtreeRoot, target, ! keepSubVal);
M->SetMachineOperandVal(3, MachineOperand::MO_CCRegister,
tmpForCC, /*def*/true);
mvec.push_back(M);
if (computeBoolVal)
{ // recompute bool using the integer condition codes
movOpCode =
ChooseMovpccAfterSub(subtreeRoot,mustClearReg,valueToMove);
}
}
else
{
// FP condition: dest of FCMP should be some FCCn register
M = new MachineInstr(ChooseFcmpInstruction(subtreeRoot));
M->SetMachineOperandVal(0, MachineOperand::MO_CCRegister,
tmpForCC);
M->SetMachineOperandVal(1,MachineOperand::MO_VirtualRegister,
subtreeRoot->leftChild()->getValue());
M->SetMachineOperandVal(2,MachineOperand::MO_VirtualRegister,
subtreeRoot->rightChild()->getValue());
mvec.push_back(M);
if (computeBoolVal)
{// recompute bool using the FP condition codes
mustClearReg = true;
valueToMove = 1;
movOpCode = ChooseMovFpccInstruction(subtreeRoot);
}
}
if (computeBoolVal)
{
if (mustClearReg)
{// Unconditionally set register to 0
M = new MachineInstr(SETHI);
M->SetMachineOperandConst(0,MachineOperand::MO_UnextendedImmed,
(int64_t)0);
M->SetMachineOperandVal(1, MachineOperand::MO_VirtualRegister,
setCCInstr);
mvec.push_back(M);
}
// Now conditionally move `valueToMove' (0 or 1) into the register
// Mark the register as a use (as well as a def) because the old
// value should be retained if the condition is false.
M = new MachineInstr(movOpCode);
M->SetMachineOperandVal(0, MachineOperand::MO_CCRegister,
tmpForCC);
M->SetMachineOperandConst(1, MachineOperand::MO_UnextendedImmed,
valueToMove);
M->SetMachineOperandVal(2, MachineOperand::MO_VirtualRegister,
setCCInstr, /*isDef*/ true,
/*isDefAndUse*/ true);
mvec.push_back(M);
}
break;
}
case 51: // reg: Load(reg)
case 52: // reg: Load(ptrreg)
mvec.push_back(new MachineInstr(ChooseLoadInstruction(
subtreeRoot->getValue()->getType())));
SetOperandsForMemInstr(mvec, subtreeRoot, target);
break;
case 55: // reg: GetElemPtr(reg)
case 56: // reg: GetElemPtrIdx(reg,reg)
// If the GetElemPtr was folded into the user (parent), it will be
// caught above. For other cases, we have to compute the address.
mvec.push_back(new MachineInstr(ADD));
SetOperandsForMemInstr(mvec, subtreeRoot, target);
break;
case 57: // reg: Alloca: Implement as 1 instruction:
{ // add %fp, offsetFromFP -> result
AllocationInst* instr =
cast<AllocationInst>(subtreeRoot->getInstruction());
unsigned int tsize =
target.findOptimalStorageSize(instr->getAllocatedType());
assert(tsize != 0);
CreateCodeForFixedSizeAlloca(target, instr, tsize, 1, mvec);
break;
}
case 58: // reg: Alloca(reg): Implement as 3 instructions:
// mul num, typeSz -> tmp
// sub %sp, tmp -> %sp
{ // add %sp, frameSizeBelowDynamicArea -> result
AllocationInst* instr =
cast<AllocationInst>(subtreeRoot->getInstruction());
const Type* eltType = instr->getAllocatedType();
// If #elements is constant, use simpler code for fixed-size allocas
int tsize = (int) target.findOptimalStorageSize(eltType);
Value* numElementsVal = NULL;
bool isArray = instr->isArrayAllocation();
if (!isArray ||
isa<Constant>(numElementsVal = instr->getArraySize()))
{ // total size is constant: generate code for fixed-size alloca
unsigned int numElements = isArray?
cast<ConstantUInt>(numElementsVal)->getValue() : 1;
CreateCodeForFixedSizeAlloca(target, instr, tsize,
numElements, mvec);
}
else // total size is not constant.
CreateCodeForVariableSizeAlloca(target, instr, tsize,
numElementsVal, mvec);
break;
}
case 61: // reg: Call
{ // Generate a direct (CALL) or indirect (JMPL). depending
// Mark the return-address register and the indirection
// register (if any) as hidden virtual registers.
// Also, mark the operands of the Call and return value (if
// any) as implicit operands of the CALL machine instruction.
//
// If this is a varargs function, floating point arguments
// have to passed in integer registers so insert
// copy-float-to-int instructions for each float operand.
//
CallInst *callInstr = cast<CallInst>(subtreeRoot->getInstruction());
Value *callee = callInstr->getCalledValue();
// Create hidden virtual register for return address, with type void*.
TmpInstruction* retAddrReg =
new TmpInstruction(PointerType::get(Type::VoidTy), callInstr);
MachineCodeForInstruction::get(callInstr).addTemp(retAddrReg);
// Generate the machine instruction and its operands.
// Use CALL for direct function calls; this optimistically assumes
// the PC-relative address fits in the CALL address field (22 bits).
// Use JMPL for indirect calls.
//
if (isa<Function>(callee))
{ // direct function call
M = new MachineInstr(CALL);
M->SetMachineOperandVal(0, MachineOperand::MO_PCRelativeDisp,
callee);
}
else
{ // indirect function call
M = new MachineInstr(JMPLCALL);
M->SetMachineOperandVal(0, MachineOperand::MO_VirtualRegister,
callee);
M->SetMachineOperandConst(1, MachineOperand::MO_SignExtendedImmed,
(int64_t) 0);
M->SetMachineOperandVal(2, MachineOperand::MO_VirtualRegister,
retAddrReg);
}
mvec.push_back(M);
const FunctionType* funcType =
cast<FunctionType>(cast<PointerType>(callee->getType())
->getElementType());
bool isVarArgs = funcType->isVarArg();
bool noPrototype = isVarArgs && funcType->getNumParams() == 0;
// Use an annotation to pass information about call arguments
// to the register allocator.
CallArgsDescriptor* argDesc = new CallArgsDescriptor(callInstr,
retAddrReg, isVarArgs, noPrototype);
M->addAnnotation(argDesc);
assert(callInstr->getOperand(0) == callee
&& "This is assumed in the loop below!");
for (unsigned i=1, N=callInstr->getNumOperands(); i < N; ++i)
{
Value* argVal = callInstr->getOperand(i);
Instruction* intArgReg = NULL;
// Check for FP arguments to varargs functions.
// Any such argument in the first $K$ args must be passed in an
// integer register, where K = #integer argument registers.
if (isVarArgs && argVal->getType()->isFloatingPoint())
{
// If it is a function with no prototype, pass value
// as an FP value as well as a varargs value
if (noPrototype)
argDesc->getArgInfo(i-1).setUseFPArgReg();
// If this arg. is in the first $K$ regs, add a copy
// float-to-int instruction to pass the value as an integer.
if (i < target.getRegInfo().GetNumOfIntArgRegs())
{
MachineCodeForInstruction &destMCFI =
MachineCodeForInstruction::get(callInstr);
intArgReg = new TmpInstruction(Type::IntTy, argVal);
destMCFI.addTemp(intArgReg);
vector<MachineInstr*> copyMvec;
target.getInstrInfo().CreateCodeToCopyFloatToInt(target,
callInstr->getParent()->getParent(),
argVal, (TmpInstruction*) intArgReg,
copyMvec, destMCFI);
mvec.insert(mvec.begin(),copyMvec.begin(),copyMvec.end());
argDesc->getArgInfo(i-1).setUseIntArgReg();
argDesc->getArgInfo(i-1).setArgCopy(intArgReg);
}
else
// Cannot fit in first $K$ regs so pass the arg on the stack
argDesc->getArgInfo(i-1).setUseStackSlot();
}
if (intArgReg)
mvec.back()->addImplicitRef(intArgReg);
mvec.back()->addImplicitRef(argVal);
}
// Add the return value as an implicit ref. The call operands
// were added above.
if (callInstr->getType() != Type::VoidTy)
mvec.back()->addImplicitRef(callInstr, /*isDef*/ true);
// For the CALL instruction, the ret. addr. reg. is also implicit
if (isa<Function>(callee))
mvec.back()->addImplicitRef(retAddrReg, /*isDef*/ true);
// delay slot
mvec.push_back(new MachineInstr(NOP));
break;
}
case 62: // reg: Shl(reg, reg)
{
Value* argVal1 = subtreeRoot->leftChild()->getValue();
Value* argVal2 = subtreeRoot->rightChild()->getValue();
Instruction* shlInstr = subtreeRoot->getInstruction();
const Type* opType = argVal1->getType();
assert((opType->isInteger() || isa<PointerType>(opType)) &&
"Shl unsupported for other types");
CreateShiftInstructions(target, shlInstr->getParent()->getParent(),
(opType == Type::LongTy)? SLLX : SLL,
argVal1, argVal2, 0, shlInstr, mvec,
MachineCodeForInstruction::get(shlInstr));
break;
}
case 63: // reg: Shr(reg, reg)
{ const Type* opType = subtreeRoot->leftChild()->getValue()->getType();
assert((opType->isInteger() || isa<PointerType>(opType)) &&
"Shr unsupported for other types");
mvec.push_back(new MachineInstr((opType->isSigned()
? ((opType == Type::LongTy)? SRAX : SRA)
: ((opType == Type::LongTy)? SRLX : SRL))));
Set3OperandsFromInstr(mvec.back(), subtreeRoot, target);
break;
}
case 64: // reg: Phi(reg,reg)
break; // don't forward the value
case 71: // reg: VReg
case 72: // reg: Constant
break; // don't forward the value
default:
assert(0 && "Unrecognized BURG rule");
break;
}
}
if (forwardOperandNum >= 0)
{ // We did not generate a machine instruction but need to use operand.
// If user is in the same tree, replace Value in its machine operand.
// If not, insert a copy instruction which should get coalesced away
// by register allocation.
if (subtreeRoot->parent() != NULL)
ForwardOperand(subtreeRoot, subtreeRoot->parent(), forwardOperandNum);
else
{
vector<MachineInstr*> minstrVec;
Instruction* instr = subtreeRoot->getInstruction();
target.getInstrInfo().
CreateCopyInstructionsByType(target,
instr->getParent()->getParent(),
instr->getOperand(forwardOperandNum),
instr, minstrVec,
MachineCodeForInstruction::get(instr));
assert(minstrVec.size() > 0);
mvec.insert(mvec.end(), minstrVec.begin(), minstrVec.end());
}
}
if (maskUnsignedResult)
{ // If result is unsigned and smaller than int reg size,
// we need to clear high bits of result value.
assert(forwardOperandNum < 0 && "Need mask but no instruction generated");
Instruction* dest = subtreeRoot->getInstruction();
if (dest->getType()->isUnsigned())
{
unsigned destSize = target.DataLayout.getTypeSize(dest->getType());
if (destSize <= 4)
{ // Mask high bits. Use a TmpInstruction to represent the
// intermediate result before masking. Since those instructions
// have already been generated, go back and substitute tmpI
// for dest in the result position of each one of them.
TmpInstruction *tmpI = new TmpInstruction(dest->getType(), dest,
NULL, "maskHi");
MachineCodeForInstruction::get(dest).addTemp(tmpI);
for (unsigned i=0, N=mvec.size(); i < N; ++i)
mvec[i]->substituteValue(dest, tmpI);
M = Create3OperandInstr_UImmed(SRL, tmpI, 4-destSize, dest);
mvec.push_back(M);
}
else if (destSize < target.DataLayout.getIntegerRegize())
assert(0 && "Unsupported type size: 32 < size < 64 bits");
}
}
}
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