From 6c0c3010dab5581a994c82d9796e05e177fb279e Mon Sep 17 00:00:00 2001 From: "Vikram S. Adve" Date: Tue, 13 Aug 2002 18:04:08 +0000 Subject: [PATCH] Several bug fixes in casting to signed int values. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@3301 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/SparcV9/SparcV9InstrInfo.cpp | 210 ++++++++++++++++-------- 1 file changed, 141 insertions(+), 69 deletions(-) diff --git a/lib/Target/SparcV9/SparcV9InstrInfo.cpp b/lib/Target/SparcV9/SparcV9InstrInfo.cpp index bf522d91067..9c82d8083e1 100644 --- a/lib/Target/SparcV9/SparcV9InstrInfo.cpp +++ b/lib/Target/SparcV9/SparcV9InstrInfo.cpp @@ -17,24 +17,38 @@ static const uint32_t MAXLO = (1 << 10) - 1; // set bits set by %lo(*) static const uint32_t MAXSIMM = (1 << 12) - 1; // set bits in simm13 field of OR -// Set a 32-bit unsigned constant in the register `dest'. +//---------------------------------------------------------------------------- +// Function: CreateSETUWConst // +// Set a 32-bit unsigned constant in the register `dest', using +// SETHI, OR in the worst case. This function correctly emulates +// the SETUW pseudo-op for SPARC v9 (if argument isSigned == false). +// +// The isSigned=true case is used to implement SETSW without duplicating code. +// +// Optimize some common cases: +// (1) Small value that fits in simm13 field of OR: don't need SETHI. +// (2) isSigned = true and C is a small negative signed value, i.e., +// high bits are 1, and the remaining bits fit in simm13(OR). +//---------------------------------------------------------------------------- + static inline void CreateSETUWConst(const TargetMachine& target, uint32_t C, - Instruction* dest, vector& mvec) + Instruction* dest, vector& mvec, + bool isSigned = false) { MachineInstr *miSETHI = NULL, *miOR = NULL; - + // In order to get efficient code, we should not generate the SETHI if // all high bits are 1 (i.e., this is a small signed value that fits in // the simm13 field of OR). So we check for and handle that case specially. // NOTE: The value C = 0x80000000 is bad: sC < 0 *and* -sC < 0. // In fact, sC == -sC, so we have to check for this explicitly. int32_t sC = (int32_t) C; - bool smallSignedValue = sC < 0 && sC != -sC && -sC < (int32_t) MAXSIMM; - + bool smallNegValue =isSigned && sC < 0 && sC != -sC && -sC < (int32_t)MAXSIMM; + // Set the high 22 bits in dest if non-zero and simm13 field of OR not enough - if (!smallSignedValue && (C & ~MAXLO) && C > MAXSIMM) + if (!smallNegValue && (C & ~MAXLO) && C > MAXSIMM) { miSETHI = Create2OperandInstr_UImmed(SETHI, C, dest); miSETHI->setOperandHi32(0); @@ -52,7 +66,7 @@ CreateSETUWConst(const TargetMachine& target, uint32_t C, } else { // unsigned or small signed value that fits in simm13 field of OR - assert(smallSignedValue || (C & ~MAXSIMM) == 0); + assert(smallNegValue || (C & ~MAXSIMM) == 0); miOR = new MachineInstr(OR); miOR->SetMachineOperandReg(0, target.getRegInfo().getZeroRegNum()); miOR->SetMachineOperandConst(1, MachineOperand::MO_SignExtendedImmed, @@ -65,37 +79,27 @@ CreateSETUWConst(const TargetMachine& target, uint32_t C, assert((miSETHI || miOR) && "Oops, no code was generated!"); } -// Set a 32-bit constant (given by a symbolic label) in the register `dest'. -// Not needed for SPARC v9 but useful to make the two SETX functions similar -static inline void -CreateSETUWLabel(const TargetMachine& target, Value* val, - Instruction* dest, vector& mvec) -{ - MachineInstr* MI; - - // Set the high 22 bits in dest - MI = Create2OperandInstr(SETHI, val, dest); - MI->setOperandHi32(0); - mvec.push_back(MI); - - // Set the low 10 bits in dest - MI = Create3OperandInstr(OR, dest, val, dest); - MI->setOperandLo32(1); - mvec.push_back(MI); -} +//---------------------------------------------------------------------------- +// Function: CreateSETSWConst +// +// Set a 32-bit signed constant in the register `dest', with sign-extension +// to 64 bits. This uses SETHI, OR, SRA in the worst case. +// This function correctly emulates the SETSW pseudo-op for SPARC v9. +// +// Optimize the same cases as SETUWConst, plus: +// (1) SRA is not needed for positive or small negative values. +//---------------------------------------------------------------------------- -// Set a 32-bit signed constant in the register `dest', -// with sign-extension to 64 bits. static inline void CreateSETSWConst(const TargetMachine& target, int32_t C, Instruction* dest, vector& mvec) { MachineInstr* MI; - + // Set the low 32 bits of dest - CreateSETUWConst(target, (uint32_t) C, dest, mvec); - + CreateSETUWConst(target, (uint32_t) C, dest, mvec, /*isSigned*/true); + // Sign-extend to the high 32 bits if needed if (C < 0 && (-C) > (int32_t) MAXSIMM) { @@ -105,7 +109,16 @@ CreateSETSWConst(const TargetMachine& target, int32_t C, } +//---------------------------------------------------------------------------- +// Function: CreateSETXConst +// // Set a 64-bit signed or unsigned constant in the register `dest'. +// Use SETUWConst for each 32 bit word, plus a left-shift-by-32 in between. +// This function correctly emulates the SETX pseudo-op for SPARC v9. +// +// Optimize the same cases as SETUWConst for each 32 bit word. +//---------------------------------------------------------------------------- + static inline void CreateSETXConst(const TargetMachine& target, uint64_t C, Instruction* tmpReg, Instruction* dest, @@ -131,7 +144,36 @@ CreateSETXConst(const TargetMachine& target, uint64_t C, } +//---------------------------------------------------------------------------- +// Function: CreateSETUWLabel +// +// Set a 32-bit constant (given by a symbolic label) in the register `dest'. +//---------------------------------------------------------------------------- + +static inline void +CreateSETUWLabel(const TargetMachine& target, Value* val, + Instruction* dest, vector& mvec) +{ + MachineInstr* MI; + + // Set the high 22 bits in dest + MI = Create2OperandInstr(SETHI, val, dest); + MI->setOperandHi32(0); + mvec.push_back(MI); + + // Set the low 10 bits in dest + MI = Create3OperandInstr(OR, dest, val, dest); + MI->setOperandLo32(1); + mvec.push_back(MI); +} + + +//---------------------------------------------------------------------------- +// Function: CreateSETXLabel +// // Set a 64-bit constant (given by a symbolic label) in the register `dest'. +//---------------------------------------------------------------------------- + static inline void CreateSETXLabel(const TargetMachine& target, Value* val, Instruction* tmpReg, Instruction* dest, @@ -166,47 +208,53 @@ CreateSETXLabel(const TargetMachine& target, } -static inline void -CreateIntSetInstruction(const TargetMachine& target, - int64_t C, Instruction* dest, - vector& mvec, - MachineCodeForInstruction& mcfi) -{ - assert(dest->getType()->isSigned() && "Use CreateUIntSetInstruction()"); - - uint64_t absC = (C >= 0)? C : -C; - if (absC > (uint32_t) ~0) - { // C does not fit in 32 bits - TmpInstruction* tmpReg = new TmpInstruction(Type::IntTy); - mcfi.addTemp(tmpReg); - CreateSETXConst(target, (uint64_t) C, tmpReg, dest, mvec); - } - else - CreateSETSWConst(target, (int32_t) C, dest, mvec); -} - +//---------------------------------------------------------------------------- +// Function: CreateUIntSetInstruction +// +// Create code to Set an unsigned constant in the register `dest'. +// Uses CreateSETUWConst, CreateSETSWConst or CreateSETXConst as needed. +// CreateSETSWConst is an optimization for the case that the unsigned value +// has all ones in the 33 high bits (so that sign-extension sets them all). +//---------------------------------------------------------------------------- static inline void CreateUIntSetInstruction(const TargetMachine& target, uint64_t C, Instruction* dest, - vector& mvec, + std::vector& mvec, MachineCodeForInstruction& mcfi) { - assert(! dest->getType()->isSigned() && "Use CreateIntSetInstruction()"); - MachineInstr* M; - - if (C > (uint32_t) ~0) + static const uint64_t lo32 = (uint32_t) ~0; + if (C <= lo32) // High 32 bits are 0. Set low 32 bits. + CreateSETUWConst(target, (uint32_t) C, dest, mvec); + else if ((C & ~lo32) == ~lo32 && (C & (1 << 31))) + { // All high 33 (not 32) bits are 1s: sign-extension will take care + // of high 32 bits, so use the sequence for signed int + CreateSETSWConst(target, (int32_t) C, dest, mvec); + } + else if (C > lo32) { // C does not fit in 32 bits - assert(dest->getType() == Type::ULongTy && "Sign extension problems"); - TmpInstruction *tmpReg = new TmpInstruction(Type::IntTy); + TmpInstruction* tmpReg = new TmpInstruction(Type::IntTy); mcfi.addTemp(tmpReg); CreateSETXConst(target, C, tmpReg, dest, mvec); } - else - CreateSETUWConst(target, C, dest, mvec); } +//---------------------------------------------------------------------------- +// Function: CreateIntSetInstruction +// +// Create code to Set a signed constant in the register `dest'. +// Really the same as CreateUIntSetInstruction. +//---------------------------------------------------------------------------- + +static inline void +CreateIntSetInstruction(const TargetMachine& target, + int64_t C, Instruction* dest, + std::vector& mvec, + MachineCodeForInstruction& mcfi) +{ + CreateUIntSetInstruction(target, (uint64_t) C, dest, mvec, mcfi); +} //--------------------------------------------------------------------------- @@ -253,27 +301,51 @@ UltraSparcInstrInfo::CreateCodeToLoadConst(const TargetMachine& target, // const Type* valType = val->getType(); - if (isa(val) || valType->isIntegral() || valType == Type::BoolTy) + if (isa(val)) { - if (isa(val)) - { - TmpInstruction* tmpReg = - new TmpInstruction(PointerType::get(val->getType()), val); - mcfi.addTemp(tmpReg); - CreateSETXLabel(target, val, tmpReg, dest, mvec); - } - else if (! dest->getType()->isSigned()) + TmpInstruction* tmpReg = + new TmpInstruction(PointerType::get(val->getType()), val); + mcfi.addTemp(tmpReg); + CreateSETXLabel(target, val, tmpReg, dest, mvec); + } + else if (valType->isIntegral() || valType == Type::BoolTy) + { + bool isValidConstant; + unsigned opSize = target.DataLayout.getTypeSize(val->getType()); + unsigned destSize = target.DataLayout.getTypeSize(dest->getType()); + + if (! dest->getType()->isSigned()) { - bool isValidConstant; uint64_t C = GetConstantValueAsUnsignedInt(val, isValidConstant); assert(isValidConstant && "Unrecognized constant"); + + if (opSize > destSize || + (val->getType()->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 + C = C & ((1U << 8*destSize) - 1); + } CreateUIntSetInstruction(target, C, dest, mvec, mcfi); } else { - bool isValidConstant; int64_t C = GetConstantValueAsSignedInt(val, isValidConstant); assert(isValidConstant && "Unrecognized constant"); + + if (opSize > destSize) + // operand is larger than dest: mask high bits + C = C & ((1U << 8*destSize) - 1); + + if (opSize > destSize || + (opSize == destSize && !val->getType()->isSigned())) + // sign-extend from destSize to 64 bits + C = ((C & (1U << (8*destSize - 1))) + ? C | ~((1U << 8*destSize) - 1) + : C); + CreateIntSetInstruction(target, C, dest, mvec, mcfi); } } -- 2.34.1