X86: Do splat promotion later, so the optimizer can chew on it first.

This catches many cases where we can emit a more efficient shuffle for a
specific mask or when the mask contains undefs. Once the splat is lowered to
unpacks we can't do that anymore.

There is a possibility of moving the promotion after pshufb matching, but I'm
not sure if pshufb with a mask loaded from memory is faster than 3 shuffles, so
I avoided that for now.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173569 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 7 insertions, 17 deletions

diff --git a/test/CodeGen/X86/avx-splat.ll b/test/CodeGen/X86/avx-splat.ll
index 67e4b40810..5c01c2cc5b 100644
--- a/test/CodeGen/X86/avx-splat.ll
+++ b/test/CodeGen/X86/avx-splat.ll
@@ -3,8 +3,8 @@
 
 ; CHECK: vpunpcklbw %xmm
 ; CHECK-NEXT: vpunpckhbw %xmm
+; CHECK-NEXT: vpshufd $85
 ; CHECK-NEXT: vinsertf128 $1
-; CHECK-NEXT: vpermilps $85
 define <32 x i8> @funcA(<32 x i8> %a) nounwind uwtable readnone ssp {
 entry:
   %shuffle = shufflevector <32 x i8> %a, <32 x i8> undef, <32 x i32> <i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5>
@@ -12,8 +12,8 @@ entry:
 }
 
 ; CHECK: vpunpckhwd %xmm
+; CHECK-NEXT: vpshufd $85
 ; CHECK-NEXT: vinsertf128 $1
-; CHECK-NEXT: vpermilps $85
 define <16 x i16> @funcB(<16 x i16> %a) nounwind uwtable readnone ssp {
 entry:
   %shuffle = shufflevector <16 x i16> %a, <16 x i16> undef, <16 x i32> <i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5, i32 5>
diff --git a/test/CodeGen/X86/vec_splat-3.ll b/test/CodeGen/X86/vec_splat-3.ll
index 293ed48866..cf0ecf4055 100644
--- a/test/CodeGen/X86/vec_splat-3.ll
+++ b/test/CodeGen/X86/vec_splat-3.ll
@@ -1,14 +1,12 @@
 ; RUN: llc <%s -march=x86 -mcpu=penryn -mattr=sse41 | FileCheck %s
 
 ; Splat test for v8i16
-; Should generate with pshufd with masks $0, $85, $170, $255 (each mask is used twice)
 define <8 x i16> @shuf_8i16_0(<8 x i16> %T0, <8 x i16> %T1) nounwind readnone {
 	%tmp6 = shufflevector <8 x i16> %T0, <8 x i16> %T1, <8 x i32> <i32 0, i32 undef, i32 undef, i32 0, i32 undef, i32 undef, i32 undef, i32 undef>
 	ret <8 x i16> %tmp6
 
 ; CHECK: shuf_8i16_0:
-; CHECK: punpcklwd
-; CHECK-NEXT: pshufd $0
+; CHECK: pshuflw $0
 }
 
 define <8 x i16> @shuf_8i16_1(<8 x i16> %T0, <8 x i16> %T1) nounwind readnone {
@@ -16,8 +14,7 @@ define <8 x i16> @shuf_8i16_1(<8 x i16> %T0, <8 x i16> %T1) nounwind readnone {
 	ret <8 x i16> %tmp6
 
 ; CHECK: shuf_8i16_1:
-; CHECK: punpcklwd
-; CHECK-NEXT: pshufd $85
+; CHECK: pshuflw $5
 }
 
 define <8 x i16> @shuf_8i16_2(<8 x i16> %T0, <8 x i16> %T1) nounwind readnone {
@@ -34,8 +31,7 @@ define <8 x i16> @shuf_8i16_3(<8 x i16> %T0, <8 x i16> %T1) nounwind readnone {
 	ret <8 x i16> %tmp6
 
 ; CHECK: shuf_8i16_3:
-; CHECK: punpcklwd
-; CHECK-NEXT: pshufd $-1
+; CHECK: pshuflw $15
 }
 
 define <8 x i16> @shuf_8i16_4(<8 x i16> %T0, <8 x i16> %T1) nounwind readnone {
@@ -43,8 +39,7 @@ define <8 x i16> @shuf_8i16_4(<8 x i16> %T0, <8 x i16> %T1) nounwind readnone {
 	ret <8 x i16> %tmp6
 
 ; CHECK: shuf_8i16_4:
-; CHECK: punpckhwd
-; CHECK-NEXT: pshufd $0
+; CHECK: movhlps
 }
 
 define <8 x i16> @shuf_8i16_5(<8 x i16> %T0, <8 x i16> %T1) nounwind readnone {
@@ -65,7 +60,6 @@ define <8 x i16> @shuf_8i16_6(<8 x i16> %T0, <8 x i16> %T1) nounwind readnone {
 ; CHECK-NEXT: pshufd $-86
 }
 
-
 define <8 x i16> @shuf_8i16_7(<8 x i16> %T0, <8 x i16> %T1) nounwind readnone {
 	%tmp6 = shufflevector <8 x i16> %T0, <8 x i16> %T1, <8 x i32> <i32 7, i32 undef, i32 undef, i32 7, i32 undef, i32 undef, i32 undef, i32 undef>
 	ret <8 x i16> %tmp6
@@ -75,8 +69,6 @@ define <8 x i16> @shuf_8i16_7(<8 x i16> %T0, <8 x i16> %T1) nounwind readnone {
 ; CHECK-NEXT: pshufd $-1
 }
 
-; Should generate with pshufd with masks $0, $85, $170, $255 (each mask is used 4 times)
-
 ; Splat test for v16i8
 define <16 x i8> @shuf_16i8_8(<16 x i8> %T0, <16 x i8> %T1) nounwind readnone {
 	%tmp6 = shufflevector <16 x i8> %T0, <16 x i8> %T1, <16 x i32> <i32 0, i32 undef, i32 undef, i32 0, i32 undef, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0>
@@ -124,9 +116,7 @@ define <16 x i8> @shuf_16i8_12(<16 x i8> %T0, <16 x i8> %T1) nounwind readnone {
 	ret <16 x i8> %tmp6
 
 ; CHECK: shuf_16i8_12:
-; CHECK: punpcklbw
-; CHECK-NEXT: punpckhbw
-; CHECK-NEXT: pshufd $0
+; CHECK: pshufd $5
 }
 
 define <16 x i8> @shuf_16i8_13(<16 x i8> %T0, <16 x i8> %T1) nounwind readnone {