SLPVectorizer: handle scalars that are extracted from vectors (using ExtractElementInst).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184325 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Nadav Rotem 2013-06-19 17:33:16 +00:00
parent dd3ef1a13b
commit 80a6d6526c
2 changed files with 103 additions and 0 deletions

View File

@ -331,6 +331,34 @@ int BoUpSLP::getTreeCost(ArrayRef<Value *> VL) {
return getTreeCost_rec(VL, 0);
}
static bool CanReuseExtract(ArrayRef<Value *> VL, unsigned VF,
VectorType *VecTy) {
// Check if all of the extracts come from the same vector and from the
// correct offset.
Value *VL0 = VL[0];
ExtractElementInst *E0 = cast<ExtractElementInst>(VL0);
Value *Vec = E0->getOperand(0);
// We have to extract from the same vector type.
if (Vec->getType() != VecTy)
return false;
// Check that all of the indices extract from the correct offset.
ConstantInt *CI = dyn_cast<ConstantInt>(E0->getOperand(1));
if (!CI || CI->getZExtValue())
return false;
for (unsigned i = 1, e = VF; i < e; ++i) {
ExtractElementInst *E = cast<ExtractElementInst>(VL[i]);
ConstantInt *CI = dyn_cast<ConstantInt>(E->getOperand(1));
if (!CI || CI->getZExtValue() != i || E->getOperand(0) != Vec)
return false;
}
return true;
}
void BoUpSLP::getTreeUses_rec(ArrayRef<Value *> VL, unsigned Depth) {
if (Depth == RecursionMaxDepth) return;
@ -386,6 +414,12 @@ void BoUpSLP::getTreeUses_rec(ArrayRef<Value *> VL, unsigned Depth) {
}
switch (Opcode) {
case Instruction::ExtractElement: {
VectorType *VecTy = VectorType::get(VL[0]->getType(), VL.size());
// No need to follow ExtractElements that are going to be optimized away.
if (CanReuseExtract(VL, VL.size(), VecTy)) return;
// Fall through.
}
case Instruction::ZExt:
case Instruction::SExt:
case Instruction::FPToUI:
@ -523,6 +557,11 @@ int BoUpSLP::getTreeCost_rec(ArrayRef<Value *> VL, unsigned Depth) {
TTI->getVectorInstrCost(Instruction::ExtractElement, VecTy, i);
switch (Opcode) {
case Instruction::ExtractElement: {
if (CanReuseExtract(VL, VL.size(), VecTy))
return 0;
return getScalarizationCost(VecTy);
}
case Instruction::ZExt:
case Instruction::SExt:
case Instruction::FPToUI:
@ -786,6 +825,11 @@ Value *BoUpSLP::vectorizeTree_rec(ArrayRef<Value *> VL, int VF) {
}
switch (Opcode) {
case Instruction::ExtractElement: {
if (CanReuseExtract(VL, VL.size(), VecTy))
return VL0->getOperand(0);
return Scalarize(VL, VecTy);
}
case Instruction::ZExt:
case Instruction::SExt:
case Instruction::FPToUI:

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@ -0,0 +1,59 @@
; RUN: opt < %s -basicaa -slp-vectorizer -dce -S -mtriple=x86_64-apple-macosx10.8.0 -mcpu=corei7-avx | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.8.0"
;CHECK: fextr
;CHECK-NOT: insertelement
;CHECK-NOT: extractelement
;CHECK: fadd <2 x double>
;CHECK: ret void
define void @fextr(double* %ptr) {
entry:
%LD = load <2 x double>* undef
%V0 = extractelement <2 x double> %LD, i32 0
%V1 = extractelement <2 x double> %LD, i32 1
%P0 = getelementptr inbounds double* %ptr, i64 0
%P1 = getelementptr inbounds double* %ptr, i64 1
%A0 = fadd double %V0, 0.0
%A1 = fadd double %V1, 1.1
store double %A0, double* %P0, align 4
store double %A1, double* %P1, align 4
ret void
}
;CHECK: fextr1
;CHECK: insertelement
;CHECK: insertelement
;CHECK: ret void
define void @fextr1(double* %ptr) {
entry:
%LD = load <2 x double>* undef
%V0 = extractelement <2 x double> %LD, i32 0
%V1 = extractelement <2 x double> %LD, i32 1
%P0 = getelementptr inbounds double* %ptr, i64 1 ; <--- incorrect order
%P1 = getelementptr inbounds double* %ptr, i64 0
%A0 = fadd double %V0, 1.2
%A1 = fadd double %V1, 3.4
store double %A0, double* %P0, align 4
store double %A1, double* %P1, align 4
ret void
}
;CHECK: fextr2
;CHECK: insertelement
;CHECK: insertelement
;CHECK: ret void
define void @fextr2(double* %ptr) {
entry:
%LD = load <4 x double>* undef
%V0 = extractelement <4 x double> %LD, i32 0 ; <--- invalid size.
%V1 = extractelement <4 x double> %LD, i32 1
%P0 = getelementptr inbounds double* %ptr, i64 0
%P1 = getelementptr inbounds double* %ptr, i64 1
%A0 = fadd double %V0, 5.5
%A1 = fadd double %V1, 6.6
store double %A0, double* %P0, align 4
store double %A1, double* %P1, align 4
ret void
}