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authorChandler Carruth <chandlerc@gmail.com>2014-06-27 18:25:23 +0000
committerChandler Carruth <chandlerc@gmail.com>2014-06-27 18:25:23 +0000
commit75504d45ec5b1c3c19b3db9ab7efe29d3d1ac1e9 (patch)
tree875c5e3cbf7485ca422e8f712e501502d6ddff8f
parentc8a1169c935ad9d3dfbdd4f72d80abf8f5acb03c (diff)
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[x86] Fix a miscompile in the new shuffle lowering uncovered by
a bootstrap. I managed to mis-remember how PACKUS worked on x86, and was using undef for the high bytes instead of zero. The fix is fairly obvious. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211922 91177308-0d34-0410-b5e6-96231b3b80d8
-rw-r--r--lib/Target/X86/X86ISelLowering.cpp26
-rw-r--r--test/CodeGen/X86/vector-shuffle-128-v16.ll42
2 files changed, 36 insertions, 32 deletions
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index c50f44daae..fa80717f99 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -7712,19 +7712,19 @@ static SDValue lowerV16I8VectorShuffle(SDValue Op, SDValue V1, SDValue V2,
return DAG.getNode(X86ISD::UNPCKL, DL, MVT::v16i8, Evens, Odds);
}
-
- SDValue LoV1 = DAG.getNode(ISD::BITCAST, DL, MVT::v8i16,
- DAG.getNode(X86ISD::UNPCKL, DL, MVT::v16i8, V1,
- DAG.getUNDEF(MVT::v8i16)));
- SDValue HiV1 = DAG.getNode(ISD::BITCAST, DL, MVT::v8i16,
- DAG.getNode(X86ISD::UNPCKH, DL, MVT::v16i8, V1,
- DAG.getUNDEF(MVT::v8i16)));
- SDValue LoV2 = DAG.getNode(ISD::BITCAST, DL, MVT::v8i16,
- DAG.getNode(X86ISD::UNPCKL, DL, MVT::v16i8, V2,
- DAG.getUNDEF(MVT::v8i16)));
- SDValue HiV2 = DAG.getNode(ISD::BITCAST, DL, MVT::v8i16,
- DAG.getNode(X86ISD::UNPCKH, DL, MVT::v16i8, V2,
- DAG.getUNDEF(MVT::v8i16)));
+ SDValue Zero = getZeroVector(MVT::v8i16, Subtarget, DAG, DL);
+ SDValue LoV1 =
+ DAG.getNode(ISD::BITCAST, DL, MVT::v8i16,
+ DAG.getNode(X86ISD::UNPCKL, DL, MVT::v16i8, V1, Zero));
+ SDValue HiV1 =
+ DAG.getNode(ISD::BITCAST, DL, MVT::v8i16,
+ DAG.getNode(X86ISD::UNPCKH, DL, MVT::v16i8, V1, Zero));
+ SDValue LoV2 =
+ DAG.getNode(ISD::BITCAST, DL, MVT::v8i16,
+ DAG.getNode(X86ISD::UNPCKL, DL, MVT::v16i8, V2, Zero));
+ SDValue HiV2 =
+ DAG.getNode(ISD::BITCAST, DL, MVT::v8i16,
+ DAG.getNode(X86ISD::UNPCKH, DL, MVT::v16i8, V2, Zero));
int V1LoBlendMask[8] = {-1, -1, -1, -1, -1, -1, -1, -1};
int V1HiBlendMask[8] = {-1, -1, -1, -1, -1, -1, -1, -1};
diff --git a/test/CodeGen/X86/vector-shuffle-128-v16.ll b/test/CodeGen/X86/vector-shuffle-128-v16.ll
index 6203aedcc1..b5e0b79088 100644
--- a/test/CodeGen/X86/vector-shuffle-128-v16.ll
+++ b/test/CodeGen/X86/vector-shuffle-128-v16.ll
@@ -23,7 +23,8 @@ define <16 x i8> @shuffle_v16i8_00_16_01_17_02_18_03_19_04_20_05_21_06_22_07_23(
define <16 x i8> @shuffle_v16i8_16_00_16_01_16_02_16_03_16_04_16_05_16_06_16_07(<16 x i8> %a, <16 x i8> %b) {
; CHECK-SSE2-LABEL: @shuffle_v16i8_16_00_16_01_16_02_16_03_16_04_16_05_16_06_16_07
-; CHECK-SSE2: punpcklbw %xmm0, %xmm1
+; CHECK-SSE2: pxor %xmm2, %xmm2
+; CHECK-SSE2-NEXT: punpcklbw %xmm2, %xmm1
; CHECK-SSE2-NEXT: pshufd {{.*}} # xmm1 = xmm1[0,1,0,3]
; CHECK-SSE2-NEXT: pshuflw {{.*}} # xmm1 = xmm1[0,0,0,0,4,5,6,7]
; CHECK-SSE2-NEXT: pshufhw {{.*}} # xmm1 = xmm1[0,1,2,3,4,4,4,4]
@@ -37,14 +38,15 @@ define <16 x i8> @shuffle_v16i8_16_00_16_01_16_02_16_03_16_04_16_05_16_06_16_07(
define <16 x i8> @shuffle_v16i8_03_02_01_00_07_06_05_04_11_10_09_08_15_14_13_12(<16 x i8> %a, <16 x i8> %b) {
; CHECK-SSE2-LABEL: @shuffle_v16i8_03_02_01_00_07_06_05_04_11_10_09_08_15_14_13_12
-; CHECK-SSE2: movdqa %xmm0, %xmm1
-; CHECK-SSE2-NEXT: punpckhbw %xmm0, %xmm1
-; CHECK-SSE2-NEXT: pshuflw {{.*}} # xmm1 = xmm1[3,2,1,0,4,5,6,7]
-; CHECK-SSE2-NEXT: pshufhw {{.*}} # xmm1 = xmm1[0,1,2,3,7,6,5,4]
-; CHECK-SSE2-NEXT: punpcklbw %xmm0, %xmm0
+; CHECK-SSE2: pxor %xmm1, %xmm1
+; CHECK-SSE2-NEXT: movdqa %xmm0, %xmm2
+; CHECK-SSE2-NEXT: punpckhbw %xmm1, %xmm2
+; CHECK-SSE2-NEXT: pshuflw {{.*}} # xmm2 = xmm2[3,2,1,0,4,5,6,7]
+; CHECK-SSE2-NEXT: pshufhw {{.*}} # xmm2 = xmm2[0,1,2,3,7,6,5,4]
+; CHECK-SSE2-NEXT: punpcklbw %xmm1, %xmm0
; CHECK-SSE2-NEXT: pshuflw {{.*}} # xmm0 = xmm0[3,2,1,0,4,5,6,7]
; CHECK-SSE2-NEXT: pshufhw {{.*}} # xmm0 = xmm0[0,1,2,3,7,6,5,4]
-; CHECK-SSE2-NEXT: packuswb %xmm1, %xmm0
+; CHECK-SSE2-NEXT: packuswb %xmm2, %xmm0
; CHECK-SSE2-NEXT: retq
%shuffle = shufflevector <16 x i8> %a, <16 x i8> %b, <16 x i32> <i32 3, i32 2, i32 1, i32 0, i32 7, i32 6, i32 5, i32 4, i32 11, i32 10, i32 9, i32 8, i32 15, i32 14, i32 13, i32 12>
ret <16 x i8> %shuffle
@@ -52,10 +54,11 @@ define <16 x i8> @shuffle_v16i8_03_02_01_00_07_06_05_04_11_10_09_08_15_14_13_12(
define <16 x i8> @shuffle_v16i8_03_02_01_00_07_06_05_04_19_18_17_16_23_22_21_20(<16 x i8> %a, <16 x i8> %b) {
; CHECK-SSE2-LABEL: @shuffle_v16i8_03_02_01_00_07_06_05_04_19_18_17_16_23_22_21_20
-; CHECK-SSE2: punpcklbw %xmm0, %xmm1
+; CHECK-SSE2: pxor %xmm2, %xmm2
+; CHECK-SSE2-NEXT: punpcklbw %xmm2, %xmm1
; CHECK-SSE2-NEXT: pshuflw {{.*}} # xmm1 = xmm1[3,2,1,0,4,5,6,7]
; CHECK-SSE2-NEXT: pshufhw {{.*}} # xmm1 = xmm1[0,1,2,3,7,6,5,4]
-; CHECK-SSE2-NEXT: punpcklbw %xmm0, %xmm0
+; CHECK-SSE2-NEXT: punpcklbw %xmm2, %xmm0
; CHECK-SSE2-NEXT: pshuflw {{.*}} # xmm0 = xmm0[3,2,1,0,4,5,6,7]
; CHECK-SSE2-NEXT: pshufhw {{.*}} # xmm0 = xmm0[0,1,2,3,7,6,5,4]
; CHECK-SSE2-NEXT: packuswb %xmm1, %xmm0
@@ -66,19 +69,20 @@ define <16 x i8> @shuffle_v16i8_03_02_01_00_07_06_05_04_19_18_17_16_23_22_21_20(
define <16 x i8> @shuffle_v16i8_03_02_01_00_31_30_29_28_11_10_09_08_23_22_21_20(<16 x i8> %a, <16 x i8> %b) {
; CHECK-SSE2-LABEL: @shuffle_v16i8_03_02_01_00_31_30_29_28_11_10_09_08_23_22_21_20
-; CHECK-SSE2: movdqa %xmm1, %xmm2
-; CHECK-SSE2-NEXT: punpcklbw %xmm0, %xmm2
-; CHECK-SSE2-NEXT: pshufhw {{.*}} # xmm2 = xmm2[0,1,2,3,7,6,5,4]
-; CHECK-SSE2-NEXT: movdqa %xmm0, %xmm3
-; CHECK-SSE2-NEXT: punpckhbw %xmm0, %xmm3
-; CHECK-SSE2-NEXT: pshuflw {{.*}} # xmm3 = xmm3[3,2,1,0,4,5,6,7]
-; CHECK-SSE2-NEXT: shufpd {{.*}} # xmm3 = xmm3[0],xmm2[1]
-; CHECK-SSE2-NEXT: punpckhbw %xmm0, %xmm1
+; CHECK-SSE2: pxor %xmm2, %xmm2
+; CHECK-SSE2-NEXT: movdqa %xmm1, %xmm3
+; CHECK-SSE2-NEXT: punpcklbw %xmm2, %xmm3
+; CHECK-SSE2-NEXT: pshufhw {{.*}} # xmm3 = xmm3[0,1,2,3,7,6,5,4]
+; CHECK-SSE2-NEXT: movdqa %xmm0, %xmm4
+; CHECK-SSE2-NEXT: punpckhbw %xmm2, %xmm4
+; CHECK-SSE2-NEXT: pshuflw {{.*}} # xmm4 = xmm4[3,2,1,0,4,5,6,7]
+; CHECK-SSE2-NEXT: shufpd {{.*}} # xmm4 = xmm4[0],xmm3[1]
+; CHECK-SSE2-NEXT: punpckhbw %xmm2, %xmm1
; CHECK-SSE2-NEXT: pshufhw {{.*}} # xmm1 = xmm1[0,1,2,3,7,6,5,4]
-; CHECK-SSE2-NEXT: punpcklbw %xmm0, %xmm0
+; CHECK-SSE2-NEXT: punpcklbw %xmm2, %xmm0
; CHECK-SSE2-NEXT: pshuflw {{.*}} # xmm0 = xmm0[3,2,1,0,4,5,6,7]
; CHECK-SSE2-NEXT: shufpd {{.*}} # xmm0 = xmm0[0],xmm1[1]
-; CHECK-SSE2-NEXT: packuswb %xmm3, %xmm0
+; CHECK-SSE2-NEXT: packuswb %xmm4, %xmm0
; CHECK-SSE2-NEXT: retq
%shuffle = shufflevector <16 x i8> %a, <16 x i8> %b, <16 x i32> <i32 3, i32 2, i32 1, i32 0, i32 31, i32 30, i32 29, i32 28, i32 11, i32 10, i32 9, i32 8, i32 23, i32 22, i32 21, i32 20>
ret <16 x i8> %shuffle