llvm/test/CodeGen/X86/pr14161.ll
Simon Pilgrim 62ba058dea [DAGCombiner] SCALAR_TO_VECTOR(EXTRACT_VECTOR_ELT(V,C)) -> VECTOR_SHUFFLE
This patch attempts to convert a SCALAR_TO_VECTOR using an operand from an EXTRACT_VECTOR_ELT into a VECTOR_SHUFFLE.

This prevents many cases of spilling scalar data between the gpr + simd registers. 

At present the optimization only accepts cases where there is no TRUNC of the scalar type (i.e. all types must match).

Differential Revision: http://reviews.llvm.org/D8132

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@231554 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-07 05:52:42 +00:00

43 lines
1.5 KiB
LLVM

; RUN: llc < %s -mtriple=x86_64-linux-pc -mcpu=corei7 | FileCheck %s
declare <4 x i32> @llvm.x86.sse41.pminud(<4 x i32>, <4 x i32>)
define <2 x i16> @good(<4 x i32>*, <4 x i8>*) {
; CHECK-LABEL: good:
; CHECK: # BB#0: # %entry
; CHECK-NEXT: movdqa (%rdi), %xmm0
; CHECK-NEXT: pminud {{.*}}(%rip), %xmm0
; CHECK-NEXT: pmovzxwq %xmm0, %xmm0
; CHECK-NEXT: retq
entry:
%2 = load <4 x i32>, <4 x i32>* %0, align 16
%3 = call <4 x i32> @llvm.x86.sse41.pminud(<4 x i32> %2, <4 x i32> <i32 127, i32 127, i32 127, i32 127>)
%4 = extractelement <4 x i32> %3, i32 0
%5 = extractelement <4 x i32> %3, i32 1
%6 = extractelement <4 x i32> %3, i32 2
%7 = extractelement <4 x i32> %3, i32 3
%8 = bitcast i32 %4 to <2 x i16>
%9 = bitcast i32 %5 to <2 x i16>
ret <2 x i16> %8
}
define <2 x i16> @bad(<4 x i32>*, <4 x i8>*) {
; CHECK-LABEL: bad:
; CHECK: # BB#0: # %entry
; CHECK-NEXT: movdqa (%rdi), %xmm0
; CHECK-NEXT: pminud {{.*}}(%rip), %xmm0
; CHECK-NEXT: pshufd {{.*#+}} xmm0 = xmm0[1,1,2,3]
; CHECK-NEXT: pmovzxwq {{.*#+}} xmm0 = xmm0[0],zero,zero,zero,xmm0[1],zero,zero,zero
; CHECK-NEXT: retq
entry:
%2 = load <4 x i32>, <4 x i32>* %0, align 16
%3 = call <4 x i32> @llvm.x86.sse41.pminud(<4 x i32> %2, <4 x i32> <i32 127, i32 127, i32 127, i32 127>)
%4 = extractelement <4 x i32> %3, i32 0
%5 = extractelement <4 x i32> %3, i32 1
%6 = extractelement <4 x i32> %3, i32 2
%7 = extractelement <4 x i32> %3, i32 3
%8 = bitcast i32 %4 to <2 x i16>
%9 = bitcast i32 %5 to <2 x i16>
ret <2 x i16> %9
}