On certain architectures we can support efficient vectorized version of
instructions if the operand value is uniform (splat) or a constant scalar.
An example of this is a vector shift on x86.
We can efficiently support
for (i = 0 ; i < ; i += 4)
w[0:3] = v[0:3] << <2, 2, 2, 2>
but not
for (i = 0; i < ; i += 4)
w[0:3] = v[0:3] << x[0:3]
This patch adds a parameter to getArithmeticInstrCost to further qualify operand
values as uniform or uniform constant.
Targets can then choose to return a different cost for instructions with such
operand values.
A follow-up commit will test this feature on x86.
radar://
13576547
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178807
91177308-0d34-0410-b5e6-
96231b3b80d8
SK_ExtractSubvector ///< ExtractSubvector Index indicates start offset.
};
+ /// \brief Additonal information about an operand's possible values.
+ enum OperandValueKind {
+ OK_AnyValue, // Operand can have any value.
+ OK_UniformValue, // Operand is uniform (splat of a value).
+ OK_UniformConstantValue // Operand is uniform constant.
+ };
+
/// \return The number of scalar or vector registers that the target has.
/// If 'Vectors' is true, it returns the number of vector registers. If it is
/// set to false, it returns the number of scalar registers.
virtual unsigned getMaximumUnrollFactor() const;
/// \return The expected cost of arithmetic ops, such as mul, xor, fsub, etc.
- virtual unsigned getArithmeticInstrCost(unsigned Opcode, Type *Ty) const;
+ virtual unsigned getArithmeticInstrCost(unsigned Opcode, Type *Ty,
+ OperandValueKind Opd1Info = OK_AnyValue,
+ OperandValueKind Opd2Info = OK_AnyValue) const;
/// \return The cost of a shuffle instruction of kind Kind and of type Tp.
/// The index and subtype parameters are used by the subvector insertion and
return true;
}
+static TargetTransformInfo::OperandValueKind getOperandInfo(Value *V) {
+ TargetTransformInfo::OperandValueKind OpInfo =
+ TargetTransformInfo::OK_AnyValue;
+
+ // Check for a splat of a constant.
+ ConstantDataVector *CDV = 0;
+ if ((CDV = dyn_cast<ConstantDataVector>(V)))
+ if (CDV->getSplatValue() != NULL)
+ OpInfo = TargetTransformInfo::OK_UniformConstantValue;
+ ConstantVector *CV = 0;
+ if ((CV = dyn_cast<ConstantVector>(V)))
+ if (CV->getSplatValue() != NULL)
+ OpInfo = TargetTransformInfo::OK_UniformConstantValue;
+
+ return OpInfo;
+}
+
unsigned CostModelAnalysis::getInstructionCost(const Instruction *I) const {
if (!TTI)
return -1;
case Instruction::And:
case Instruction::Or:
case Instruction::Xor: {
- return TTI->getArithmeticInstrCost(I->getOpcode(), I->getType());
+ TargetTransformInfo::OperandValueKind Op1VK =
+ getOperandInfo(I->getOperand(0));
+ TargetTransformInfo::OperandValueKind Op2VK =
+ getOperandInfo(I->getOperand(1));
+ return TTI->getArithmeticInstrCost(I->getOpcode(), I->getType(), Op1VK,
+ Op2VK);
}
case Instruction::Select: {
const SelectInst *SI = cast<SelectInst>(I);
}
unsigned TargetTransformInfo::getArithmeticInstrCost(unsigned Opcode,
- Type *Ty) const {
- return PrevTTI->getArithmeticInstrCost(Opcode, Ty);
+ Type *Ty,
+ OperandValueKind Op1Info,
+ OperandValueKind Op2Info) const {
+ return PrevTTI->getArithmeticInstrCost(Opcode, Ty, Op1Info, Op2Info);
}
unsigned TargetTransformInfo::getShuffleCost(ShuffleKind Kind, Type *Tp,
return 1;
}
- unsigned getArithmeticInstrCost(unsigned Opcode, Type *Ty) const {
+ unsigned getArithmeticInstrCost(unsigned Opcode, Type *Ty, OperandValueKind,
+ OperandValueKind) const {
return 1;
}
virtual unsigned getNumberOfRegisters(bool Vector) const;
virtual unsigned getMaximumUnrollFactor() const;
virtual unsigned getRegisterBitWidth(bool Vector) const;
- virtual unsigned getArithmeticInstrCost(unsigned Opcode, Type *Ty) const;
+ virtual unsigned getArithmeticInstrCost(unsigned Opcode, Type *Ty,
+ OperandValueKind,
+ OperandValueKind) const;
virtual unsigned getShuffleCost(ShuffleKind Kind, Type *Tp,
int Index, Type *SubTp) const;
virtual unsigned getCastInstrCost(unsigned Opcode, Type *Dst,
return 1;
}
-unsigned BasicTTI::getArithmeticInstrCost(unsigned Opcode, Type *Ty) const {
+unsigned BasicTTI::getArithmeticInstrCost(unsigned Opcode, Type *Ty,
+ OperandValueKind,
+ OperandValueKind) const {
// Check if any of the operands are vector operands.
int ISD = TLI->InstructionOpcodeToISD(Opcode);
assert(ISD && "Invalid opcode");
virtual unsigned getNumberOfRegisters(bool Vector) const;
virtual unsigned getRegisterBitWidth(bool Vector) const;
virtual unsigned getMaximumUnrollFactor() const;
- virtual unsigned getArithmeticInstrCost(unsigned Opcode, Type *Ty) const;
+ virtual unsigned getArithmeticInstrCost(unsigned Opcode, Type *Ty,
+ OperandValueKind,
+ OperandValueKind) const;
virtual unsigned getShuffleCost(ShuffleKind Kind, Type *Tp,
int Index, Type *SubTp) const;
virtual unsigned getCastInstrCost(unsigned Opcode, Type *Dst,
return 2;
}
-unsigned PPCTTI::getArithmeticInstrCost(unsigned Opcode, Type *Ty) const {
+unsigned PPCTTI::getArithmeticInstrCost(unsigned Opcode, Type *Ty,
+ OperandValueKind Op1Info,
+ OperandValueKind Op2Info) const {
assert(TLI->InstructionOpcodeToISD(Opcode) && "Invalid opcode");
// Fallback to the default implementation.
- return TargetTransformInfo::getArithmeticInstrCost(Opcode, Ty);
+ return TargetTransformInfo::getArithmeticInstrCost(Opcode, Ty, Op1Info,
+ Op2Info);
}
unsigned PPCTTI::getShuffleCost(ShuffleKind Kind, Type *Tp, int Index,
virtual unsigned getNumberOfRegisters(bool Vector) const;
virtual unsigned getRegisterBitWidth(bool Vector) const;
virtual unsigned getMaximumUnrollFactor() const;
- virtual unsigned getArithmeticInstrCost(unsigned Opcode, Type *Ty) const;
+ virtual unsigned getArithmeticInstrCost(unsigned Opcode, Type *Ty,
+ OperandValueKind,
+ OperandValueKind) const;
virtual unsigned getShuffleCost(ShuffleKind Kind, Type *Tp,
int Index, Type *SubTp) const;
virtual unsigned getCastInstrCost(unsigned Opcode, Type *Dst,
return 2;
}
-unsigned X86TTI::getArithmeticInstrCost(unsigned Opcode, Type *Ty) const {
+unsigned X86TTI::getArithmeticInstrCost(unsigned Opcode, Type *Ty,
+ OperandValueKind Op1Info,
+ OperandValueKind Op2Info) const {
// Legalize the type.
std::pair<unsigned, MVT> LT = TLI->getTypeLegalizationCost(Ty);
return 6;
// Fallback to the default implementation.
- return TargetTransformInfo::getArithmeticInstrCost(Opcode, Ty);
+ return TargetTransformInfo::getArithmeticInstrCost(Opcode, Ty, Op1Info,
+ Op2Info);
}
unsigned X86TTI::getShuffleCost(ShuffleKind Kind, Type *Tp, int Index,