Commit b96ee8f5 authored by Simon Pilgrim's avatar Simon Pilgrim Committed by Tom Stellard
Browse files

[X86] combineX86ShuffleChain - ensure we only peek through bitcasts to vectors (PR51858) 

When searching for hidden identity shuffles (added at rG41146bfe82aecc79961c3de898cda02998172e4b), only peek through bitcasts to the source operand if it is a vector type as well.

(cherry picked from commit dcba9941)
parent dda88bfc

llvm/lib/Target/X86/X86ISelLowering.cpp

+1 −1
Original line number Diff line number Diff line
@@ -35823,7 +35823,7 @@ static SDValue combineX86ShuffleChain(ArrayRef<SDValue> Inputs, SDValue Root, 














  // See if the shuffle is a hidden identity shuffle - repeated args in HOPs















  // etc. can be simplified.













  if (VT1 == VT2 && VT1.getSizeInBits() == RootSizeInBits) {













  if (VT1 == VT2 && VT1.getSizeInBits() == RootSizeInBits && VT1.isVector()) {















    SmallVector<int> ScaledMask, IdentityMask;















    unsigned NumElts = VT1.getVectorNumElements();















    if (BaseMask.size() <= NumElts &&

























llvm/test/CodeGen/X86/vector-reduce-mul.ll



+58
−0






























Original line number
Diff line number
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@@ -2344,6 +2344,64 @@ define i8 @illegal_v8i8(i8 %a0, <8 x i8>* %a1) {













  ret i8 %mul















}





























define i8 @PR51858(i128 %arg) {













; SSE2-LABEL: PR51858:













; SSE2:       # %bb.0:













; SSE2-NEXT:    movq %rdi, %xmm0













; SSE2-NEXT:    movq %rsi, %xmm1













; SSE2-NEXT:    punpcklbw {{.*#+}} xmm1 = xmm1[0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7]













; SSE2-NEXT:    punpcklbw {{.*#+}} xmm0 = xmm0[0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7]













; SSE2-NEXT:    pmullw %xmm1, %xmm0













; SSE2-NEXT:    pshufd {{.*#+}} xmm1 = xmm0[2,3,2,3]













; SSE2-NEXT:    pmullw %xmm0, %xmm1













; SSE2-NEXT:    pshufd {{.*#+}} xmm0 = xmm1[1,1,1,1]













; SSE2-NEXT:    pmullw %xmm1, %xmm0













; SSE2-NEXT:    movdqa %xmm0, %xmm1













; SSE2-NEXT:    psrld $16, %xmm1













; SSE2-NEXT:    pmullw %xmm0, %xmm1













; SSE2-NEXT:    movd %xmm1, %eax













; SSE2-NEXT:    # kill: def $al killed $al killed $eax













; SSE2-NEXT:    retq













;













; SSE41-LABEL: PR51858:













; SSE41:       # %bb.0:













; SSE41-NEXT:    movq %rdi, %xmm0













; SSE41-NEXT:    movq %rsi, %xmm1













; SSE41-NEXT:    pmovzxbw {{.*#+}} xmm1 = xmm1[0],zero,xmm1[1],zero,xmm1[2],zero,xmm1[3],zero,xmm1[4],zero,xmm1[5],zero,xmm1[6],zero,xmm1[7],zero













; SSE41-NEXT:    pmovzxbw {{.*#+}} xmm0 = xmm0[0],zero,xmm0[1],zero,xmm0[2],zero,xmm0[3],zero,xmm0[4],zero,xmm0[5],zero,xmm0[6],zero,xmm0[7],zero













; SSE41-NEXT:    pmullw %xmm1, %xmm0













; SSE41-NEXT:    pshufd {{.*#+}} xmm1 = xmm0[2,3,2,3]













; SSE41-NEXT:    pmullw %xmm0, %xmm1













; SSE41-NEXT:    pshufd {{.*#+}} xmm0 = xmm1[1,1,1,1]













; SSE41-NEXT:    pmullw %xmm1, %xmm0













; SSE41-NEXT:    movdqa %xmm0, %xmm1













; SSE41-NEXT:    psrld $16, %xmm1













; SSE41-NEXT:    pmullw %xmm0, %xmm1













; SSE41-NEXT:    movd %xmm1, %eax













; SSE41-NEXT:    # kill: def $al killed $al killed $eax













; SSE41-NEXT:    retq













;













; AVX-LABEL: PR51858:













; AVX:       # %bb.0:













; AVX-NEXT:    vmovq %rdi, %xmm0













; AVX-NEXT:    vmovq %rsi, %xmm1













; AVX-NEXT:    vpmovzxbw {{.*#+}} xmm1 = xmm1[0],zero,xmm1[1],zero,xmm1[2],zero,xmm1[3],zero,xmm1[4],zero,xmm1[5],zero,xmm1[6],zero,xmm1[7],zero













; AVX-NEXT:    vpmovzxbw {{.*#+}} xmm0 = xmm0[0],zero,xmm0[1],zero,xmm0[2],zero,xmm0[3],zero,xmm0[4],zero,xmm0[5],zero,xmm0[6],zero,xmm0[7],zero













; AVX-NEXT:    vpmullw %xmm1, %xmm0, %xmm0













; AVX-NEXT:    vpshufd {{.*#+}} xmm1 = xmm0[2,3,2,3]













; AVX-NEXT:    vpmullw %xmm1, %xmm0, %xmm0













; AVX-NEXT:    vpshufd {{.*#+}} xmm1 = xmm0[1,1,1,1]













; AVX-NEXT:    vpmullw %xmm1, %xmm0, %xmm0













; AVX-NEXT:    vpsrld $16, %xmm0, %xmm1













; AVX-NEXT:    vpmullw %xmm1, %xmm0, %xmm0













; AVX-NEXT:    vmovd %xmm0, %eax













; AVX-NEXT:    # kill: def $al killed $al killed $eax













; AVX-NEXT:    retq













  %vec = bitcast i128 %arg to <16 x i8>













  %red = tail call i8 @llvm.vector.reduce.mul.v16i8(<16 x i8> %vec)













  ret i8 %red













}





























declare i64 @llvm.vector.reduce.mul.v2i64(<2 x i64>)















declare i64 @llvm.vector.reduce.mul.v4i64(<4 x i64>)















declare i64 @llvm.vector.reduce.mul.v8i64(<8 x i64>)