llvm::BasicTTIImplBase::getPartialReductionCost

Synopsis

Declared in <llvm/CodeGen/BasicTTIImpl.h>

InstructionCost
getPartialReductionCost(
    unsigned int Opcode,
    Type* InputTypeA,
    Type* InputTypeB,
    Type* AccumType,
    ElementCount VF,
    TTI::PartialReductionExtendKind OpAExtend,
    TTI::PartialReductionExtendKind OpBExtend,
    std::optional<unsigned int> BinOp,
    TTI::TargetCostKind CostKind,
    std::optional<FastMathFlags> FMF) const override;

Description

Partial reductions use llvm.vector.partial.reduce.* intrinsics that accumulate into AccumType from a second vector with element count VF. BinOp and the extend kinds describe optional extends or a binary operation on extends.

Return Value

The cost of a partial reduction to a narrower vector.

Parameters

Name	Description
Opcode	Reduction opcode.
InputTypeA	Type of the first input before any extend.
InputTypeB	Type of the second input before any extend, or null.
AccumType	Accumulator vector element/result type.
VF	Element count of the vector being reduced into the accumulator.
OpAExtend	Extend kind applied to the first input, if any.
OpBExtend	Extend kind applied to the second input, if any.
BinOp	Optional binary opcode on extended inputs.
CostKind	Kind of cost to compute.
FMF	Fast-math flags for FP partial reductions, else nullopt.