[X86][SSE] Avoid vector byte shuffles with zero by using pshufb to create zeros

pshufb can shuffle in zero bytes as well as bytes from a source vector - we can use this to avoid having to shuffle 2 vectors and ORing the result when the used inputs from a vector are all zeroable.

Differential Revision: http://reviews.llvm.org/D6878

llvm-svn: 225551

1 files changed, 76 insertions, 112 deletions

diff --git a/llvm/test/CodeGen/X86/vector-shuffle-128-v16.ll b/llvm/test/CodeGen/X86/vector-shuffle-128-v16.ll
index 131410606aa..fd25cc96330 100644
--- a/llvm/test/CodeGen/X86/vector-shuffle-128-v16.ll
+++ b/llvm/test/CodeGen/X86/vector-shuffle-128-v16.ll
@@ -467,32 +467,23 @@ define <16 x i8> @PR20540(<8 x i8> %a) {
 ; SSE2-NEXT:    pshufhw {{.*#+}} xmm1 = xmm1[0,1,2,3,4,4,4,4]
 ; SSE2-NEXT:    packuswb %xmm1, %xmm0
 ; SSE2-NEXT:    retq
-;
-; SSSE3-LABEL: PR20540:
-; SSSE3:       # BB#0:
-; SSSE3-NEXT:    pxor %xmm1, %xmm1
-; SSSE3-NEXT:    pshufb {{.*#+}} xmm1 = zero,zero,zero,zero,zero,zero,zero,zero,xmm1[0,0,0,0,0,0,0,0]
-; SSSE3-NEXT:    pshufb {{.*#+}} xmm0 = xmm0[0,2,4,6,8,10,12,14],zero,zero,zero,zero,zero,zero,zero,zero
-; SSSE3-NEXT:    por %xmm1, %xmm0
-; SSSE3-NEXT:    retq
-;
-; SSE41-LABEL: PR20540:
-; SSE41:       # BB#0:
-; SSE41-NEXT:    pxor %xmm1, %xmm1
-; SSE41-NEXT:    pshufb {{.*#+}} xmm1 = zero,zero,zero,zero,zero,zero,zero,zero,xmm1[0,0,0,0,0,0,0,0]
-; SSE41-NEXT:    pshufb {{.*#+}} xmm0 = xmm0[0,2,4,6,8,10,12,14],zero,zero,zero,zero,zero,zero,zero,zero
-; SSE41-NEXT:    por %xmm1, %xmm0
-; SSE41-NEXT:    retq
-;
-; AVX-LABEL: PR20540:
-; AVX:       # BB#0:
-; AVX-NEXT:    vpxor %xmm1, %xmm1, %xmm1
-; AVX-NEXT:    vpshufb {{.*#+}} xmm1 = zero,zero,zero,zero,zero,zero,zero,zero,xmm1[0,0,0,0,0,0,0,0]
-; AVX-NEXT:    vpshufb {{.*#+}} xmm0 = xmm0[0,2,4,6,8,10,12,14],zero,zero,zero,zero,zero,zero,zero,zero
-; AVX-NEXT:    vpor %xmm1, %xmm0, %xmm0
-; AVX-NEXT:    retq
-  %shuffle = shufflevector <8 x i8> %a, <8 x i8> zeroinitializer, <16 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 8, i32 8, i32 8, i32 8, i32 8, i32 8, i32 8>
-  ret <16 x i8> %shuffle
+;

+; SSSE3-LABEL: PR20540:

+; SSSE3:       # BB#0:

+; SSSE3-NEXT:    pshufb {{.*#+}} xmm0 = xmm0[0,2,4,6,8,10,12,14],zero,zero,zero,zero,zero,zero,zero,zero

+; SSSE3-NEXT:    retq

+;

+; SSE41-LABEL: PR20540:

+; SSE41:       # BB#0:

+; SSE41-NEXT:    pshufb {{.*#+}} xmm0 = xmm0[0,2,4,6,8,10,12,14],zero,zero,zero,zero,zero,zero,zero,zero

+; SSE41-NEXT:    retq

+;

+; AVX-LABEL: PR20540:

+; AVX:       # BB#0:

+; AVX-NEXT:    vpshufb {{.*#+}} xmm0 = xmm0[0,2,4,6,8,10,12,14],zero,zero,zero,zero,zero,zero,zero,zero

+; AVX-NEXT:    retq

+  %shuffle = shufflevector <8 x i8> %a, <8 x i8> zeroinitializer, <16 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 8, i32 8, i32 8, i32 8, i32 8, i32 8, i32 8>

+  ret <16 x i8> %shuffle

 }
 
 define <16 x i8> @shuffle_v16i8_16_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz(i8 %i) {
@@ -502,34 +493,25 @@ define <16 x i8> @shuffle_v16i8_16_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz(
 ; SSE2-NEXT:    movd %eax, %xmm0
 ; SSE2-NEXT:    retq
 ;
-; SSSE3-LABEL: shuffle_v16i8_16_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:
-; SSSE3:       # BB#0:
-; SSSE3-NEXT:    movd %edi, %xmm0
-; SSSE3-NEXT:    pxor %xmm1, %xmm1
-; SSSE3-NEXT:    pshufb {{.*#+}} xmm1 = zero,xmm1[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15]
-; SSSE3-NEXT:    pshufb {{.*#+}} xmm0 = xmm0[0],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero
-; SSSE3-NEXT:    por %xmm1, %xmm0
-; SSSE3-NEXT:    retq
-;
-; SSE41-LABEL: shuffle_v16i8_16_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:
-; SSE41:       # BB#0:
-; SSE41-NEXT:    movd %edi, %xmm0
-; SSE41-NEXT:    pxor %xmm1, %xmm1
-; SSE41-NEXT:    pshufb {{.*#+}} xmm1 = zero,xmm1[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15]
-; SSE41-NEXT:    pshufb {{.*#+}} xmm0 = xmm0[0],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero
-; SSE41-NEXT:    por %xmm1, %xmm0
-; SSE41-NEXT:    retq
-;
-; AVX-LABEL: shuffle_v16i8_16_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:
-; AVX:       # BB#0:
-; AVX-NEXT:    vmovd %edi, %xmm0
-; AVX-NEXT:    vpxor %xmm1, %xmm1, %xmm1
-; AVX-NEXT:    vpshufb {{.*#+}} xmm1 = zero,xmm1[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15]
-; AVX-NEXT:    vpshufb {{.*#+}} xmm0 = xmm0[0],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero
-; AVX-NEXT:    vpor %xmm0, %xmm1, %xmm0
-; AVX-NEXT:    retq
-  %a = insertelement <16 x i8> undef, i8 %i, i32 0
-  %shuffle = shufflevector <16 x i8> zeroinitializer, <16 x i8> %a, <16 x i32> <i32 16, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15>
+; SSSE3-LABEL: shuffle_v16i8_16_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:

+; SSSE3:       # BB#0:

+; SSSE3-NEXT:    movd %edi, %xmm0

+; SSSE3-NEXT:    pshufb {{.*#+}} xmm0 = xmm0[0],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero

+; SSSE3-NEXT:    retq

+;

+; SSE41-LABEL: shuffle_v16i8_16_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:

+; SSE41:       # BB#0:

+; SSE41-NEXT:    movd %edi, %xmm0

+; SSE41-NEXT:    pshufb {{.*#+}} xmm0 = xmm0[0],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero

+; SSE41-NEXT:    retq

+;

+; AVX-LABEL: shuffle_v16i8_16_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:

+; AVX:       # BB#0:

+; AVX-NEXT:    vmovd %edi, %xmm0

+; AVX-NEXT:    vpshufb {{.*#+}} xmm0 = xmm0[0],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero

+; AVX-NEXT:    retq

+  %a = insertelement <16 x i8> undef, i8 %i, i32 0

+  %shuffle = shufflevector <16 x i8> zeroinitializer, <16 x i8> %a, <16 x i32> <i32 16, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15>

   ret <16 x i8> %shuffle
 }
 
@@ -541,34 +523,25 @@ define <16 x i8> @shuffle_v16i8_zz_zz_zz_zz_zz_16_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz(
 ; SSE2-NEXT:    pslldq {{.*#+}} xmm0 = zero,zero,zero,zero,zero,xmm0[0,1,2,3,4,5,6,7,8,9,10]
 ; SSE2-NEXT:    retq
 ;
-; SSSE3-LABEL: shuffle_v16i8_zz_zz_zz_zz_zz_16_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:
-; SSSE3:       # BB#0:
-; SSSE3-NEXT:    movd %edi, %xmm0
-; SSSE3-NEXT:    pxor %xmm1, %xmm1
-; SSSE3-NEXT:    pshufb {{.*#+}} xmm1 = xmm1[0,0,0,0,0],zero,xmm1[0,0,0,0,0,0,0,0,0,0]
-; SSSE3-NEXT:    pshufb {{.*#+}} xmm0 = zero,zero,zero,zero,zero,xmm0[0],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero
-; SSSE3-NEXT:    por %xmm1, %xmm0
-; SSSE3-NEXT:    retq
-;
-; SSE41-LABEL: shuffle_v16i8_zz_zz_zz_zz_zz_16_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:
-; SSE41:       # BB#0:
-; SSE41-NEXT:    movd %edi, %xmm0
-; SSE41-NEXT:    pxor %xmm1, %xmm1
-; SSE41-NEXT:    pshufb {{.*#+}} xmm1 = xmm1[0,0,0,0,0],zero,xmm1[0,0,0,0,0,0,0,0,0,0]
-; SSE41-NEXT:    pshufb {{.*#+}} xmm0 = zero,zero,zero,zero,zero,xmm0[0],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero
-; SSE41-NEXT:    por %xmm1, %xmm0
-; SSE41-NEXT:    retq
-;
-; AVX-LABEL: shuffle_v16i8_zz_zz_zz_zz_zz_16_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:
-; AVX:       # BB#0:
-; AVX-NEXT:    vmovd %edi, %xmm0
-; AVX-NEXT:    vpxor %xmm1, %xmm1, %xmm1
-; AVX-NEXT:    vpshufb {{.*#+}} xmm1 = xmm1[0,0,0,0,0],zero,xmm1[0,0,0,0,0,0,0,0,0,0]
-; AVX-NEXT:    vpshufb {{.*#+}} xmm0 = zero,zero,zero,zero,zero,xmm0[0],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero
-; AVX-NEXT:    vpor %xmm0, %xmm1, %xmm0
-; AVX-NEXT:    retq
-  %a = insertelement <16 x i8> undef, i8 %i, i32 0
-  %shuffle = shufflevector <16 x i8> zeroinitializer, <16 x i8> %a, <16 x i32> <i32 0, i32 0, i32 0, i32 0, i32 0, i32 16, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0>
+; SSSE3-LABEL: shuffle_v16i8_zz_zz_zz_zz_zz_16_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:

+; SSSE3:       # BB#0:

+; SSSE3-NEXT:    movd %edi, %xmm0

+; SSSE3-NEXT:    pshufb {{.*#+}} xmm0 = zero,zero,zero,zero,zero,xmm0[0],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero

+; SSSE3-NEXT:    retq

+;

+; SSE41-LABEL: shuffle_v16i8_zz_zz_zz_zz_zz_16_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:

+; SSE41:       # BB#0:

+; SSE41-NEXT:    movd %edi, %xmm0

+; SSE41-NEXT:    pshufb {{.*#+}} xmm0 = zero,zero,zero,zero,zero,xmm0[0],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero

+; SSE41-NEXT:    retq

+;

+; AVX-LABEL: shuffle_v16i8_zz_zz_zz_zz_zz_16_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:

+; AVX:       # BB#0:

+; AVX-NEXT:    vmovd %edi, %xmm0

+; AVX-NEXT:    vpshufb {{.*#+}} xmm0 = zero,zero,zero,zero,zero,xmm0[0],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero

+; AVX-NEXT:    retq

+  %a = insertelement <16 x i8> undef, i8 %i, i32 0

+  %shuffle = shufflevector <16 x i8> zeroinitializer, <16 x i8> %a, <16 x i32> <i32 0, i32 0, i32 0, i32 0, i32 0, i32 16, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0>

   ret <16 x i8> %shuffle
 }
 
@@ -598,36 +571,27 @@ define <16 x i8> @shuffle_v16i8_zz_zz_19_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz(
 ; SSE2-NEXT:    retq
 ;
 ; SSSE3-LABEL: shuffle_v16i8_zz_zz_19_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:
-; SSSE3:       # BB#0:
-; SSSE3-NEXT:    movd %edi, %xmm0
-; SSSE3-NEXT:    pslldq {{.*#+}} xmm0 = zero,zero,zero,xmm0[0,1,2,3,4,5,6,7,8,9,10,11,12]
-; SSSE3-NEXT:    pxor %xmm1, %xmm1
-; SSSE3-NEXT:    pshufb {{.*#+}} xmm1 = xmm1[0,1],zero,xmm1[3,4,5,6,7,8,9,10,11,12,13,14,15]
-; SSSE3-NEXT:    pshufb {{.*#+}} xmm0 = zero,zero,xmm0[3],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero
-; SSSE3-NEXT:    por %xmm1, %xmm0
-; SSSE3-NEXT:    retq
-;
-; SSE41-LABEL: shuffle_v16i8_zz_zz_19_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:
-; SSE41:       # BB#0:
-; SSE41-NEXT:    movd %edi, %xmm0
-; SSE41-NEXT:    pslldq {{.*#+}} xmm0 = zero,zero,zero,xmm0[0,1,2,3,4,5,6,7,8,9,10,11,12]
-; SSE41-NEXT:    pxor %xmm1, %xmm1
-; SSE41-NEXT:    pshufb {{.*#+}} xmm1 = xmm1[0,1],zero,xmm1[3,4,5,6,7,8,9,10,11,12,13,14,15]
-; SSE41-NEXT:    pshufb {{.*#+}} xmm0 = zero,zero,xmm0[3],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero
-; SSE41-NEXT:    por %xmm1, %xmm0
-; SSE41-NEXT:    retq
-;
-; AVX-LABEL: shuffle_v16i8_zz_zz_19_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:
-; AVX:       # BB#0:
-; AVX-NEXT:    vmovd %edi, %xmm0
-; AVX-NEXT:    vpslldq {{.*#+}} xmm0 = zero,zero,zero,xmm0[0,1,2,3,4,5,6,7,8,9,10,11,12]
-; AVX-NEXT:    vpxor %xmm1, %xmm1, %xmm1
-; AVX-NEXT:    vpshufb {{.*#+}} xmm1 = xmm1[0,1],zero,xmm1[3,4,5,6,7,8,9,10,11,12,13,14,15]
-; AVX-NEXT:    vpshufb {{.*#+}} xmm0 = zero,zero,xmm0[3],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero
-; AVX-NEXT:    vpor %xmm0, %xmm1, %xmm0
-; AVX-NEXT:    retq
-  %a = insertelement <16 x i8> undef, i8 %i, i32 3
-  %shuffle = shufflevector <16 x i8> zeroinitializer, <16 x i8> %a, <16 x i32> <i32 0, i32 1, i32 19, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15>
+; SSSE3:       # BB#0:

+; SSSE3-NEXT:    movd %edi, %xmm0

+; SSSE3-NEXT:    pslldq {{.*#+}} xmm0 = zero,zero,zero,xmm0[0,1,2,3,4,5,6,7,8,9,10,11,12]

+; SSSE3-NEXT:    pshufb {{.*#+}} xmm0 = zero,zero,xmm0[3],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero

+; SSSE3-NEXT:    retq

+;

+; SSE41-LABEL: shuffle_v16i8_zz_zz_19_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:

+; SSE41:       # BB#0:

+; SSE41-NEXT:    movd %edi, %xmm0

+; SSE41-NEXT:    pslldq {{.*#+}} xmm0 = zero,zero,zero,xmm0[0,1,2,3,4,5,6,7,8,9,10,11,12]

+; SSE41-NEXT:    pshufb {{.*#+}} xmm0 = zero,zero,xmm0[3],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero

+; SSE41-NEXT:    retq

+;

+; AVX-LABEL: shuffle_v16i8_zz_zz_19_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz_zz:

+; AVX:       # BB#0:

+; AVX-NEXT:    vmovd %edi, %xmm0

+; AVX-NEXT:    vpslldq {{.*#+}} xmm0 = zero,zero,zero,xmm0[0,1,2,3,4,5,6,7,8,9,10,11,12]

+; AVX-NEXT:    vpshufb {{.*#+}} xmm0 = zero,zero,xmm0[3],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero

+; AVX-NEXT:    retq

+  %a = insertelement <16 x i8> undef, i8 %i, i32 3

+  %shuffle = shufflevector <16 x i8> zeroinitializer, <16 x i8> %a, <16 x i32> <i32 0, i32 1, i32 19, i32 3, i32 4, i32 5, i32 6, i32 7, i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15>

   ret <16 x i8> %shuffle
 }