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Remove the assumption that FP's are either float or

Browse Source 
double from some of the many places in the optimizers
it appears, and do something reasonable with x86
long double.
Make APInt::dump() public, remove newline, use it to
dump ConstantSDNode's.
Allow APFloats in FoldingSet.
Expand X86 backend handling of long doubles (conversions
to/from int, mostly).

llvm-svn: 41967
This commit is contained in:
Dale Johannesen 2007-09-14 22:26:36 +00:00
parent 13797e4a74
commit 575bd6070a
13 changed files with 118 additions and 56 deletions
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10
include/llvm/ADT/APInt.h
View File

@ -153,11 +153,6 @@ class APInt {
const APInt &RHS, uint32_t rhsWords,
APInt *Quotient, APInt *Remainder);
#ifndef NDEBUG
/// @brief debug method
void dump() const;
#endif
public:
/// @name Constructors
/// @{
@ -1165,6 +1160,11 @@ public:
static void tcSetLeastSignificantBits(integerPart *, unsigned int,
unsigned int bits);
#ifndef NDEBUG
/// @brief debug method
void dump() const;
#endif
/// @}
};

2
include/llvm/ADT/FoldingSet.h
View File

@ -18,6 +18,7 @@
#include "llvm/Support/DataTypes.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/APFloat.h"
#include <string>
namespace llvm {
@ -153,6 +154,7 @@ public:
void AddInteger(uint64_t I);
void AddFloat(float F);
void AddDouble(double D);
void AddAPFloat(const APFloat& apf);
void AddString(const std::string &String);
/// ComputeHash - Compute a strong hash value for this NodeID, used to

3
include/llvm/Constants.h
View File

@ -231,6 +231,9 @@ public:
/// considers -0.0 to be null as well as 0.0. :(
virtual bool isNullValue() const;
// Get a negative zero.
static ConstantFP *getNegativeZero(const Type* Ty);
/// isExactlyValue - We don't rely on operator== working on double values, as
/// it returns true for things that are clearly not equal, like -0.0 and 0.0.
/// As such, this method can be used to do an exact bit-for-bit comparison of

41
lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
View File

@ -486,15 +486,23 @@ static SDOperand ExpandConstantFP(ConstantFPSDNode *CFP, bool UseCP,
// double.
MVT::ValueType VT = CFP->getValueType(0);
bool isDouble = VT == MVT::f64;
ConstantFP *LLVMC = ConstantFP::get(isDouble ? Type::DoubleTy :
Type::FloatTy, CFP->getValueAPF());
ConstantFP *LLVMC = ConstantFP::get(VT==MVT::f64 ? Type::DoubleTy :
VT==MVT::f32 ? Type::FloatTy :
VT==MVT::f80 ? Type::X86_FP80Ty :
VT==MVT::f128 ? Type::FP128Ty :
VT==MVT::ppcf128 ? Type::PPC_FP128Ty :
Type::VoidTy, // error
CFP->getValueAPF());
if (!UseCP) {
if (VT!=MVT::f64 && VT!=MVT::f32)
assert(0 && "Invalid type expansion");
return DAG.getConstant(LLVMC->getValueAPF().convertToAPInt().getZExtValue(),
isDouble ? MVT::i64 : MVT::i32);
}
if (isDouble && CFP->isValueValidForType(MVT::f32, CFP->getValueAPF()) &&
// Only do this if the target has a native EXTLOAD instruction from f32.
// Do not try to be clever about long doubles (so far)
TLI.isLoadXLegal(ISD::EXTLOAD, MVT::f32)) {
LLVMC = cast<ConstantFP>(ConstantExpr::getFPTrunc(LLVMC,Type::FloatTy));
VT = MVT::f32;
@ -1976,19 +1984,22 @@ SDOperand SelectionDAGLegalize::LegalizeOp(SDOperand Op) {
// to phase ordering between legalized code and the dag combiner. This
// probably means that we need to integrate dag combiner and legalizer
// together.
if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(ST->getValue())) {
// We generally can't do this one for long doubles.
if (ConstantFPSDNode *CFP =dyn_cast<ConstantFPSDNode>(ST->getValue())) {
if (CFP->getValueType(0) == MVT::f32) {
Tmp3 = DAG.getConstant((uint32_t)CFP->getValueAPF().
convertToAPInt().getZExtValue(),
MVT::i32);
} else {
assert(CFP->getValueType(0) == MVT::f64 && "Unknown FP type!");
Result = DAG.getStore(Tmp1, Tmp3, Tmp2, ST->getSrcValue(),
SVOffset, isVolatile, Alignment);
break;
} else if (CFP->getValueType(0) == MVT::f64) {
Tmp3 = DAG.getConstant(CFP->getValueAPF().convertToAPInt().
getZExtValue(), MVT::i64);
Result = DAG.getStore(Tmp1, Tmp3, Tmp2, ST->getSrcValue(),
SVOffset, isVolatile, Alignment);
break;
}
Result = DAG.getStore(Tmp1, Tmp3, Tmp2, ST->getSrcValue(),
SVOffset, isVolatile, Alignment);
break;
}
switch (getTypeAction(ST->getStoredVT())) {
@ -4609,12 +4620,16 @@ ExpandIntToFP(bool isSigned, MVT::ValueType DestTy, SDOperand Source) {
SDOperand FudgeInReg;
if (DestTy == MVT::f32)
FudgeInReg = DAG.getLoad(MVT::f32, DAG.getEntryNode(), CPIdx, NULL, 0);
else {
assert(DestTy == MVT::f64 && "Unexpected conversion");
else if (DestTy == MVT::f64)
// FIXME: Avoid the extend by construction the right constantpool?
FudgeInReg = DAG.getExtLoad(ISD::EXTLOAD, MVT::f64, DAG.getEntryNode(),
CPIdx, NULL, 0, MVT::f32);
}
else if (DestTy == MVT::f80)
FudgeInReg = DAG.getExtLoad(ISD::EXTLOAD, MVT::f80, DAG.getEntryNode(),
CPIdx, NULL, 0, MVT::f32);
else
assert(0 && "Unexpected conversion");
MVT::ValueType SCVT = SignedConv.getValueType();
if (SCVT != DestTy) {
// Destination type needs to be expanded as well. The FADD now we are
@ -4722,9 +4737,11 @@ SDOperand SelectionDAGLegalize::ExpandLegalINT_TO_FP(bool isSigned,
if (DestVT == MVT::f64) {
// do nothing
Result = Sub;
} else {
} else if (DestVT == MVT::f32) {
// if f32 then cast to f32
Result = DAG.getNode(ISD::FP_ROUND, MVT::f32, Sub);
} else if (DestVT == MVT::f80) {
Result = DAG.getNode(ISD::FP_EXTEND, MVT::f80, Sub);
}
return Result;
}

28
lib/CodeGen/SelectionDAG/SelectionDAG.cpp
View File

@ -322,13 +322,7 @@ static void AddNodeIDNode(FoldingSetNodeID &ID, SDNode *N) {
break;
case ISD::TargetConstantFP:
case ISD::ConstantFP: {
APFloat V = cast<ConstantFPSDNode>(N)->getValueAPF();
if (&V.getSemantics() == &APFloat::IEEEdouble)
ID.AddDouble(V.convertToDouble());
else if (&V.getSemantics() == &APFloat::IEEEsingle)
ID.AddDouble((double)V.convertToFloat());
else
assert(0);
ID.AddAPFloat(cast<ConstantFPSDNode>(N)->getValueAPF());
break;
}
case ISD::TargetGlobalAddress:
@ -709,25 +703,21 @@ SDOperand SelectionDAG::getConstantFP(const APFloat& V, MVT::ValueType VT,
MVT::ValueType EltVT =
MVT::isVector(VT) ? MVT::getVectorElementType(VT) : VT;
bool isDouble = (EltVT == MVT::f64);
double Val = isDouble ? V.convertToDouble() : (double)V.convertToFloat();
// Do the map lookup using the actual bit pattern for the floating point
// value, so that we don't have problems with 0.0 comparing equal to -0.0, and
// we don't have issues with SNANs.
unsigned Opc = isTarget ? ISD::TargetConstantFP : ISD::ConstantFP;
// ?? Should we store float/double/longdouble separately in ID?
FoldingSetNodeID ID;
AddNodeIDNode(ID, Opc, getVTList(EltVT), 0, 0);
ID.AddDouble(Val);
ID.AddAPFloat(V);
void *IP = 0;
SDNode *N = NULL;
if ((N = CSEMap.FindNodeOrInsertPos(ID, IP)))
if (!MVT::isVector(VT))
return SDOperand(N, 0);
if (!N) {
N = new ConstantFPSDNode(isTarget,
isDouble ? APFloat(Val) : APFloat((float)Val), EltVT);
N = new ConstantFPSDNode(isTarget, V, EltVT);
CSEMap.InsertNode(N, IP);
AllNodes.push_back(N);
}
@ -3724,9 +3714,15 @@ void SDNode::dump(const SelectionDAG *G) const {
if (const ConstantSDNode *CSDN = dyn_cast<ConstantSDNode>(this)) {
cerr << "<" << CSDN->getValue() << ">";
} else if (const ConstantFPSDNode *CSDN = dyn_cast<ConstantFPSDNode>(this)) {
cerr << "<" << (&CSDN->getValueAPF().getSemantics()==&APFloat::IEEEsingle ?
CSDN->getValueAPF().convertToFloat() :
CSDN->getValueAPF().convertToDouble()) << ">";
if (&CSDN->getValueAPF().getSemantics()==&APFloat::IEEEsingle)
cerr << "<" << CSDN->getValueAPF().convertToFloat() << ">";
else if (&CSDN->getValueAPF().getSemantics()==&APFloat::IEEEdouble)
cerr << "<" << CSDN->getValueAPF().convertToDouble() << ">";
else {
cerr << "<APFloat(";
CSDN->getValueAPF().convertToAPInt().dump();
cerr << ")>";
}
} else if (const GlobalAddressSDNode *GADN =
dyn_cast<GlobalAddressSDNode>(this)) {
int offset = GADN->getOffset();

5
lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
View File

@ -2004,8 +2004,7 @@ void SelectionDAGLowering::visitSub(User &I) {
const Type *ElTy = DestTy->getElementType();
if (ElTy->isFloatingPoint()) {
unsigned VL = DestTy->getNumElements();
std::vector<Constant*> NZ(VL, ConstantFP::get(ElTy,
ElTy==Type::FloatTy ? APFloat(-0.0f) : APFloat(-0.0)));
std::vector<Constant*> NZ(VL, ConstantFP::getNegativeZero(ElTy));
Constant *CNZ = ConstantVector::get(&NZ[0], NZ.size());
if (CV == CNZ) {
SDOperand Op2 = getValue(I.getOperand(1));
@ -2017,7 +2016,7 @@ void SelectionDAGLowering::visitSub(User &I) {
}
if (Ty->isFloatingPoint()) {
if (ConstantFP *CFP = dyn_cast<ConstantFP>(I.getOperand(0)))
if (CFP->isExactlyValue(-0.0)) {
if (CFP->isExactlyValue(ConstantFP::getNegativeZero(Ty)->getValueAPF())) {
SDOperand Op2 = getValue(I.getOperand(1));
setValue(&I, DAG.getNode(ISD::FNEG, Op2.getValueType(), Op2));
return;

2
lib/Support/APInt.cpp
View File

@ -2009,7 +2009,7 @@ void APInt::dump() const
cerr << pVal[i-1] << " ";
}
cerr << " U(" << this->toStringUnsigned(10) << ") S("
<< this->toStringSigned(10) << ")\n" << std::setbase(10);
<< this->toStringSigned(10) << ")" << std::setbase(10);
}
#endif

6
lib/Support/FoldingSet.cpp
View File

@ -56,6 +56,12 @@ void FoldingSetImpl::NodeID::AddFloat(float F) {
void FoldingSetImpl::NodeID::AddDouble(double D) {
AddInteger(DoubleToBits(D));
}
void FoldingSetImpl::NodeID::AddAPFloat(const APFloat& apf) {
APInt api = apf.convertToAPInt();
const uint64_t *p = api.getRawData();
for (int i=0; i<api.getNumWords(); i++)
AddInteger(*p++);
}
void FoldingSetImpl::NodeID::AddString(const std::string &String) {
unsigned Size = String.size();
Bits.push_back(Size);

3
lib/Target/CBackend/CBackend.cpp
View File

@ -604,6 +604,9 @@ void CWriter::printConstantVector(ConstantVector *CP) {
// only deal in IEEE FP).
//
static bool isFPCSafeToPrint(const ConstantFP *CFP) {
// Do long doubles the hard way for now.
if (CFP->getType()!=Type::FloatTy && CFP->getType()!=Type::DoubleTy)
return false;
APFloat APF = APFloat(CFP->getValueAPF()); // copy
if (CFP->getType()==Type::FloatTy)
APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven);

32
lib/Target/X86/X86ISelLowering.cpp
View File

@ -99,9 +99,11 @@ X86TargetLowering::X86TargetLowering(TargetMachine &TM)
setOperationAction(ISD::SINT_TO_FP , MVT::i1 , Promote);
setOperationAction(ISD::SINT_TO_FP , MVT::i8 , Promote);
// SSE has no i16 to fp conversion, only i32
if (X86ScalarSSE)
if (X86ScalarSSE) {
setOperationAction(ISD::SINT_TO_FP , MVT::i16 , Promote);
else {
// f32 and f64 cases are Legal, f80 case is not
setOperationAction(ISD::SINT_TO_FP , MVT::i32 , Custom);
} else {
setOperationAction(ISD::SINT_TO_FP , MVT::i16 , Custom);
setOperationAction(ISD::SINT_TO_FP , MVT::i32 , Custom);
}
@ -119,6 +121,8 @@ X86TargetLowering::X86TargetLowering(TargetMachine &TM)
if (X86ScalarSSE) {
setOperationAction(ISD::FP_TO_SINT , MVT::i16 , Promote);
// f32 and f64 cases are Legal, f80 case is not
setOperationAction(ISD::FP_TO_SINT , MVT::i32 , Custom);
} else {
setOperationAction(ISD::FP_TO_SINT , MVT::i16 , Custom);
setOperationAction(ISD::FP_TO_SINT , MVT::i32 , Custom);
@ -189,11 +193,13 @@ X86TargetLowering::X86TargetLowering(TargetMachine &TM)
setOperationAction(ISD::SELECT , MVT::i32 , Custom);
setOperationAction(ISD::SELECT , MVT::f32 , Custom);
setOperationAction(ISD::SELECT , MVT::f64 , Custom);
setOperationAction(ISD::SELECT , MVT::f80 , Custom);
setOperationAction(ISD::SETCC , MVT::i8 , Custom);
setOperationAction(ISD::SETCC , MVT::i16 , Custom);
setOperationAction(ISD::SETCC , MVT::i32 , Custom);
setOperationAction(ISD::SETCC , MVT::f32 , Custom);
setOperationAction(ISD::SETCC , MVT::f64 , Custom);
setOperationAction(ISD::SETCC , MVT::f80 , Custom);
if (Subtarget->is64Bit()) {
setOperationAction(ISD::SELECT , MVT::i64 , Custom);
setOperationAction(ISD::SETCC , MVT::i64 , Custom);
@ -334,6 +340,9 @@ X86TargetLowering::X86TargetLowering(TargetMachine &TM)
// Long double always uses X87.
addRegisterClass(MVT::f80, X86::RFP80RegisterClass);
setOperationAction(ISD::UNDEF, MVT::f80, Expand);
setOperationAction(ISD::FCOPYSIGN, MVT::f80, Expand);
setOperationAction(ISD::ConstantFP, MVT::f80, Expand);
// First set operation action for all vector types to expand. Then we
// will selectively turn on ones that can be effectively codegen'd.
@ -3326,9 +3335,14 @@ SDOperand X86TargetLowering::LowerSINT_TO_FP(SDOperand Op, SelectionDAG &DAG) {
SDOperand Chain = DAG.getStore(DAG.getEntryNode(), Op.getOperand(0),
StackSlot, NULL, 0);
// These are really Legal; caller falls through into that case.
if (SrcVT==MVT::i32 && Op.getValueType() != MVT::f80 && X86ScalarSSE)
return Result;
// Build the FILD
SDVTList Tys;
if (X86ScalarSSE)
bool useSSE = X86ScalarSSE && Op.getValueType() != MVT::f80;
if (useSSE)
Tys = DAG.getVTList(MVT::f64, MVT::Other, MVT::Flag);
else
Tys = DAG.getVTList(Op.getValueType(), MVT::Other);
@ -3336,10 +3350,10 @@ SDOperand X86TargetLowering::LowerSINT_TO_FP(SDOperand Op, SelectionDAG &DAG) {
Ops.push_back(Chain);
Ops.push_back(StackSlot);
Ops.push_back(DAG.getValueType(SrcVT));
Result = DAG.getNode(X86ScalarSSE ? X86ISD::FILD_FLAG :X86ISD::FILD,
Result = DAG.getNode(useSSE ? X86ISD::FILD_FLAG :X86ISD::FILD,
Tys, &Ops[0], Ops.size());
if (X86ScalarSSE) {
if (useSSE) {
Chain = Result.getValue(1);
SDOperand InFlag = Result.getValue(2);
@ -3368,11 +3382,17 @@ SDOperand X86TargetLowering::LowerFP_TO_SINT(SDOperand Op, SelectionDAG &DAG) {
"Unknown FP_TO_SINT to lower!");
// We lower FP->sint64 into FISTP64, followed by a load, all to a temporary
// stack slot.
SDOperand Result;
MachineFunction &MF = DAG.getMachineFunction();
unsigned MemSize = MVT::getSizeInBits(Op.getValueType())/8;
int SSFI = MF.getFrameInfo()->CreateStackObject(MemSize, MemSize);
SDOperand StackSlot = DAG.getFrameIndex(SSFI, getPointerTy());
// These are really Legal.
if (Op.getValueType() == MVT::i32 && X86ScalarSSE &&
Op.getOperand(0).getValueType() != MVT::f80)
return Result;
unsigned Opc;
switch (Op.getValueType()) {
default: assert(0 && "Invalid FP_TO_SINT to lower!");
@ -3383,7 +3403,7 @@ SDOperand X86TargetLowering::LowerFP_TO_SINT(SDOperand Op, SelectionDAG &DAG) {
SDOperand Chain = DAG.getEntryNode();
SDOperand Value = Op.getOperand(0);
if (X86ScalarSSE) {
if (X86ScalarSSE && Op.getOperand(0).getValueType() != MVT::f80) {
assert(Op.getValueType() == MVT::i64 && "Invalid FP_TO_SINT to lower!");
Chain = DAG.getStore(Chain, Value, StackSlot, NULL, 0);
SDVTList Tys = DAG.getVTList(Op.getOperand(0).getValueType(), MVT::Other);

8
lib/Target/X86/X86RegisterInfo.cpp
View File

@ -168,7 +168,11 @@ void X86RegisterInfo::storeRegToStackSlot(MachineBasicBlock &MBB,
Opc = X86::MOV32_mr;
} else if (RC == &X86::GR16_RegClass) {
Opc = X86::MOV16_mr;
} else if (RC == &X86::RFP80RegClass) {
Opc = X86::ST_FpP80m; // pops
} else if (RC == &X86::RFP64RegClass || RC == &X86::RSTRegClass) {
/// FIXME spilling long double values as 64 bit does not work.
/// We need RST80, unfortunately.
Opc = X86::ST_Fp64m;
} else if (RC == &X86::RFP32RegClass) {
Opc = X86::ST_Fp32m;
@ -205,6 +209,8 @@ void X86RegisterInfo::loadRegFromStackSlot(MachineBasicBlock &MBB,
Opc = X86::MOV32_rm;
} else if (RC == &X86::GR16_RegClass) {
Opc = X86::MOV16_rm;
} else if (RC == &X86::RFP80RegClass) {
Opc = X86::LD_Fp80m;
} else if (RC == &X86::RFP64RegClass || RC == &X86::RSTRegClass) {
Opc = X86::LD_Fp64m;
} else if (RC == &X86::RFP32RegClass) {
@ -245,6 +251,8 @@ void X86RegisterInfo::copyRegToReg(MachineBasicBlock &MBB,
Opc = X86::MOV_Fp3232;
} else if (RC == &X86::RFP64RegClass || RC == &X86::RSTRegClass) {
Opc = X86::MOV_Fp6464;
} else if (RC == &X86::RFP80RegClass) {
Opc = X86::MOV_Fp8080;
} else if (RC == &X86::FR32RegClass) {
Opc = X86::FsMOVAPSrr;
} else if (RC == &X86::FR64RegClass) {

9
lib/Transforms/Scalar/InstructionCombining.cpp
View File

@ -1949,7 +1949,8 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
if (RHSC->isNullValue())
return ReplaceInstUsesWith(I, LHS);
} else if (ConstantFP *CFP = dyn_cast<ConstantFP>(RHSC)) {
if (CFP->isExactlyValue(-0.0))
if (CFP->isExactlyValue(ConstantFP::getNegativeZero
(I.getType())->getValueAPF()))
return ReplaceInstUsesWith(I, LHS);
}
@ -2349,8 +2350,10 @@ Instruction *InstCombiner::visitMul(BinaryOperator &I) {
// "In IEEE floating point, x*1 is not equivalent to x for nans. However,
// ANSI says we can drop signals, so we can do this anyway." (from GCC)
if (Op1F->isExactlyValue(1.0))
return ReplaceInstUsesWith(I, Op0); // Eliminate 'mul double %X, 1.0'
// We need a better interface for long double here.
if (Op1->getType() == Type::FloatTy || Op1->getType() == Type::DoubleTy)
if (Op1F->isExactlyValue(1.0))
return ReplaceInstUsesWith(I, Op0); // Eliminate 'mul double %X, 1.0'
}
if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0))

25
lib/VMCore/Constants.cpp
View File

@ -103,17 +103,19 @@ bool Constant::ContainsRelocations() const {
// Static constructor to create a '0' constant of arbitrary type...
Constant *Constant::getNullValue(const Type *Ty) {
static uint64_t zero[2] = {0, 0};
switch (Ty->getTypeID()) {
case Type::IntegerTyID:
return ConstantInt::get(Ty, 0);
case Type::FloatTyID:
return ConstantFP::get(Ty, APFloat(0.0f));
return ConstantFP::get(Ty, APFloat(APInt(32, 0)));
case Type::DoubleTyID:
return ConstantFP::get(Ty, APFloat(0.0));
return ConstantFP::get(Ty, APFloat(APInt(64, 0)));
case Type::X86_FP80TyID:
case Type::PPC_FP128TyID:
return ConstantFP::get(Ty, APFloat(APInt(80, 2, zero)));
case Type::FP128TyID:
return ConstantFP::get(Ty, APFloat(0.0)); //FIXME
case Type::PPC_FP128TyID:
return ConstantFP::get(Ty, APFloat(APInt(128, 2, zero)));
case Type::PointerTyID:
return ConstantPointerNull::get(cast<PointerType>(Ty));
case Type::StructTyID:
@ -259,6 +261,12 @@ bool ConstantFP::isNullValue() const {
return Val.isZero() && !Val.isNegative();
}
ConstantFP *ConstantFP::getNegativeZero(const Type *Ty) {
APFloat apf = cast <ConstantFP>(Constant::getNullValue(Ty))->getValueAPF();
apf.changeSign();
return ConstantFP::get(Ty, apf);
}
bool ConstantFP::isExactlyValue(const APFloat& V) const {
return Val.bitwiseIsEqual(V);
}
@ -1925,15 +1933,12 @@ Constant *ConstantExpr::getZeroValueForNegationExpr(const Type *Ty) {
if (const VectorType *PTy = dyn_cast<VectorType>(Ty))
if (PTy->getElementType()->isFloatingPoint()) {
std::vector<Constant*> zeros(PTy->getNumElements(),
ConstantFP::get(PTy->getElementType(),
PTy->getElementType()==Type::FloatTy ?
APFloat(-0.0f) : APFloat(0.0)));
ConstantFP::getNegativeZero(PTy->getElementType()));
return ConstantVector::get(PTy, zeros);
}
if (Ty->isFloatingPoint())
return ConstantFP::get(Ty, Ty==Type::FloatTy ? APFloat(-0.0f) :
APFloat(-0.0));
if (Ty->isFloatingPoint())
return ConstantFP::getNegativeZero(Ty);
return Constant::getNullValue(Ty);
}