[InstCombine] Update InstCombine to use poison instead of undef for shufflevector's placeholder (1/3)

This patch is for fixing potential shufflevector-related bugs like D93818.
As D93818, this patch change shufflevector's default placeholder to poison.
To reduce risk, it was divided into several patches, and this patch is for InstCombineCasts.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D110226

clang/test/Headers/wasm.c

@@ -825,7 +825,7 @@ v128_t test_u64x2_replace_lane(v128_t a, uint64_t b) {
 // CHECK-NEXT:  entry:
 // CHECK-NEXT:    [[VECINIT_I:%.*]] = insertelement <4 x float> undef, float [[A:%.*]], i32 0
 // CHECK-NEXT:    [[TMP0:%.*]] = bitcast <4 x float> [[VECINIT_I]] to <4 x i32>
-// CHECK-NEXT:    [[TMP1:%.*]] = shufflevector <4 x i32> [[TMP0]], <4 x i32> undef, <4 x i32> zeroinitializer
+// CHECK-NEXT:    [[TMP1:%.*]] = shufflevector <4 x i32> [[TMP0]], <4 x i32> poison, <4 x i32> zeroinitializer
 // CHECK-NEXT:    ret <4 x i32> [[TMP1]]
 //
 v128_t test_f32x4_splat(float a) {
@@ -1598,7 +1598,7 @@ v128_t test_i8x16_popcnt(v128_t a) {
 // CHECK-NEXT:    [[TMP0:%.*]] = bitcast <4 x i32> [[A:%.*]] to <16 x i8>
 // CHECK-NEXT:    [[TMP1:%.*]] = trunc i32 [[B:%.*]] to i8
 // CHECK-NEXT:    [[TMP2:%.*]] = insertelement <16 x i8> undef, i8 [[TMP1]], i32 0
-// CHECK-NEXT:    [[SH_PROM_I:%.*]] = shufflevector <16 x i8> [[TMP2]], <16 x i8> undef, <16 x i32> zeroinitializer
+// CHECK-NEXT:    [[SH_PROM_I:%.*]] = shufflevector <16 x i8> [[TMP2]], <16 x i8> poison, <16 x i32> zeroinitializer
 // CHECK-NEXT:    [[SHL_I:%.*]] = shl <16 x i8> [[TMP0]], [[SH_PROM_I]]
 // CHECK-NEXT:    [[TMP3:%.*]] = bitcast <16 x i8> [[SHL_I]] to <4 x i32>
 // CHECK-NEXT:    ret <4 x i32> [[TMP3]]
@@ -1612,7 +1612,7 @@ v128_t test_i8x16_shl(v128_t a, uint32_t b) {
 // CHECK-NEXT:    [[TMP0:%.*]] = bitcast <4 x i32> [[A:%.*]] to <16 x i8>
 // CHECK-NEXT:    [[TMP1:%.*]] = trunc i32 [[B:%.*]] to i8
 // CHECK-NEXT:    [[TMP2:%.*]] = insertelement <16 x i8> undef, i8 [[TMP1]], i32 0
-// CHECK-NEXT:    [[SH_PROM_I:%.*]] = shufflevector <16 x i8> [[TMP2]], <16 x i8> undef, <16 x i32> zeroinitializer
+// CHECK-NEXT:    [[SH_PROM_I:%.*]] = shufflevector <16 x i8> [[TMP2]], <16 x i8> poison, <16 x i32> zeroinitializer
 // CHECK-NEXT:    [[SHR_I:%.*]] = ashr <16 x i8> [[TMP0]], [[SH_PROM_I]]
 // CHECK-NEXT:    [[TMP3:%.*]] = bitcast <16 x i8> [[SHR_I]] to <4 x i32>
 // CHECK-NEXT:    ret <4 x i32> [[TMP3]]
@@ -1626,7 +1626,7 @@ v128_t test_i8x16_shr(v128_t a, uint32_t b) {
 // CHECK-NEXT:    [[TMP0:%.*]] = bitcast <4 x i32> [[A:%.*]] to <16 x i8>
 // CHECK-NEXT:    [[TMP1:%.*]] = trunc i32 [[B:%.*]] to i8
 // CHECK-NEXT:    [[TMP2:%.*]] = insertelement <16 x i8> undef, i8 [[TMP1]], i32 0
-// CHECK-NEXT:    [[SH_PROM_I:%.*]] = shufflevector <16 x i8> [[TMP2]], <16 x i8> undef, <16 x i32> zeroinitializer
+// CHECK-NEXT:    [[SH_PROM_I:%.*]] = shufflevector <16 x i8> [[TMP2]], <16 x i8> poison, <16 x i32> zeroinitializer
 // CHECK-NEXT:    [[SHR_I:%.*]] = lshr <16 x i8> [[TMP0]], [[SH_PROM_I]]
 // CHECK-NEXT:    [[TMP3:%.*]] = bitcast <16 x i8> [[SHR_I]] to <4 x i32>
 // CHECK-NEXT:    ret <4 x i32> [[TMP3]]
@@ -1819,7 +1819,7 @@ uint32_t test_i16x8_bitmask(v128_t a) {
 // CHECK-NEXT:    [[TMP0:%.*]] = bitcast <4 x i32> [[A:%.*]] to <8 x i16>
 // CHECK-NEXT:    [[TMP1:%.*]] = trunc i32 [[B:%.*]] to i16
 // CHECK-NEXT:    [[TMP2:%.*]] = insertelement <8 x i16> undef, i16 [[TMP1]], i32 0
-// CHECK-NEXT:    [[SH_PROM_I:%.*]] = shufflevector <8 x i16> [[TMP2]], <8 x i16> undef, <8 x i32> zeroinitializer
+// CHECK-NEXT:    [[SH_PROM_I:%.*]] = shufflevector <8 x i16> [[TMP2]], <8 x i16> poison, <8 x i32> zeroinitializer
 // CHECK-NEXT:    [[SHL_I:%.*]] = shl <8 x i16> [[TMP0]], [[SH_PROM_I]]
 // CHECK-NEXT:    [[TMP3:%.*]] = bitcast <8 x i16> [[SHL_I]] to <4 x i32>
 // CHECK-NEXT:    ret <4 x i32> [[TMP3]]
@@ -1833,7 +1833,7 @@ v128_t test_i16x8_shl(v128_t a, uint32_t b) {
 // CHECK-NEXT:    [[TMP0:%.*]] = bitcast <4 x i32> [[A:%.*]] to <8 x i16>
 // CHECK-NEXT:    [[TMP1:%.*]] = trunc i32 [[B:%.*]] to i16
 // CHECK-NEXT:    [[TMP2:%.*]] = insertelement <8 x i16> undef, i16 [[TMP1]], i32 0
-// CHECK-NEXT:    [[SH_PROM_I:%.*]] = shufflevector <8 x i16> [[TMP2]], <8 x i16> undef, <8 x i32> zeroinitializer
+// CHECK-NEXT:    [[SH_PROM_I:%.*]] = shufflevector <8 x i16> [[TMP2]], <8 x i16> poison, <8 x i32> zeroinitializer
 // CHECK-NEXT:    [[SHR_I:%.*]] = ashr <8 x i16> [[TMP0]], [[SH_PROM_I]]
 // CHECK-NEXT:    [[TMP3:%.*]] = bitcast <8 x i16> [[SHR_I]] to <4 x i32>
 // CHECK-NEXT:    ret <4 x i32> [[TMP3]]
@@ -1847,7 +1847,7 @@ v128_t test_i16x8_shr(v128_t a, uint32_t b) {
 // CHECK-NEXT:    [[TMP0:%.*]] = bitcast <4 x i32> [[A:%.*]] to <8 x i16>
 // CHECK-NEXT:    [[TMP1:%.*]] = trunc i32 [[B:%.*]] to i16
 // CHECK-NEXT:    [[TMP2:%.*]] = insertelement <8 x i16> undef, i16 [[TMP1]], i32 0
-// CHECK-NEXT:    [[SH_PROM_I:%.*]] = shufflevector <8 x i16> [[TMP2]], <8 x i16> undef, <8 x i32> zeroinitializer
+// CHECK-NEXT:    [[SH_PROM_I:%.*]] = shufflevector <8 x i16> [[TMP2]], <8 x i16> poison, <8 x i32> zeroinitializer
 // CHECK-NEXT:    [[SHR_I:%.*]] = lshr <8 x i16> [[TMP0]], [[SH_PROM_I]]
 // CHECK-NEXT:    [[TMP3:%.*]] = bitcast <8 x i16> [[SHR_I]] to <4 x i32>
 // CHECK-NEXT:    ret <4 x i32> [[TMP3]]

llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp

@@ -333,7 +333,7 @@ Instruction *InstCombinerImpl::commonCastTransforms(CastInst &CI) {
         SrcTy->getNumElements() == DestTy->getNumElements() &&
         SrcTy->getPrimitiveSizeInBits() == DestTy->getPrimitiveSizeInBits()) {
       Value *CastX = Builder.CreateCast(CI.getOpcode(), X, DestTy);
-      return new ShuffleVectorInst(CastX, UndefValue::get(DestTy), Mask);
+      return new ShuffleVectorInst(CastX, Mask);
     }
   }
 
@@ -701,10 +701,10 @@ static Instruction *shrinkSplatShuffle(TruncInst &Trunc,
   if (Shuf && Shuf->hasOneUse() && match(Shuf->getOperand(1), m_Undef()) &&
       is_splat(Shuf->getShuffleMask()) &&
       Shuf->getType() == Shuf->getOperand(0)->getType()) {
-    // trunc (shuf X, Undef, SplatMask) --> shuf (trunc X), Undef, SplatMask
+    // trunc (shuf X, Undef, SplatMask) --> shuf (trunc X), Poison, SplatMask
-    Constant *NarrowUndef = UndefValue::get(Trunc.getType());
+    // trunc (shuf X, Poison, SplatMask) --> shuf (trunc X), Poison, SplatMask
     Value *NarrowOp = Builder.CreateTrunc(Shuf->getOperand(0), Trunc.getType());
-    return new ShuffleVectorInst(NarrowOp, NarrowUndef, Shuf->getShuffleMask());
+    return new ShuffleVectorInst(NarrowOp, Shuf->getShuffleMask());
   }
 
   return nullptr;
@@ -2144,9 +2144,9 @@ optimizeVectorResizeWithIntegerBitCasts(Value *InVal, VectorType *DestTy,
   if (SrcElts > DestElts) {
     // If we're shrinking the number of elements (rewriting an integer
     // truncate), just shuffle in the elements corresponding to the least
-    // significant bits from the input and use undef as the second shuffle
+    // significant bits from the input and use poison as the second shuffle
     // input.
-    V2 = UndefValue::get(SrcTy);
+    V2 = PoisonValue::get(SrcTy);
     // Make sure the shuffle mask selects the "least significant bits" by
     // keeping elements from back of the src vector for big endian, and from the
     // front for little endian.

llvm/test/Transforms/InstCombine/X86/x86-f16c-inseltpoison.ll

@@ -25,7 +25,7 @@ define <4 x float> @demand_vcvtph2ps_128(<8 x i16> %A) {
 define <8 x float> @demand_vcvtph2ps_256(<8 x i16> %A) {
 ; CHECK-LABEL: @demand_vcvtph2ps_256(
 ; CHECK-NEXT:    [[TMP1:%.*]] = bitcast <8 x i16> [[A:%.*]] to <8 x half>
-; CHECK-NEXT:    [[TMP2:%.*]] = shufflevector <8 x half> [[TMP1]], <8 x half> undef, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 0, i32 1, i32 2, i32 3>
+; CHECK-NEXT:    [[TMP2:%.*]] = shufflevector <8 x half> [[TMP1]], <8 x half> poison, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 0, i32 1, i32 2, i32 3>
 ; CHECK-NEXT:    [[CVTPH2PS:%.*]] = fpext <8 x half> [[TMP2]] to <8 x float>
 ; CHECK-NEXT:    ret <8 x float> [[CVTPH2PS]]
 ;

llvm/test/Transforms/InstCombine/X86/x86-f16c.ll

@@ -25,7 +25,7 @@ define <4 x float> @demand_vcvtph2ps_128(<8 x i16> %A) {
 define <8 x float> @demand_vcvtph2ps_256(<8 x i16> %A) {
 ; CHECK-LABEL: @demand_vcvtph2ps_256(
 ; CHECK-NEXT:    [[TMP1:%.*]] = bitcast <8 x i16> [[A:%.*]] to <8 x half>
-; CHECK-NEXT:    [[TMP2:%.*]] = shufflevector <8 x half> [[TMP1]], <8 x half> undef, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 0, i32 1, i32 2, i32 3>
+; CHECK-NEXT:    [[TMP2:%.*]] = shufflevector <8 x half> [[TMP1]], <8 x half> poison, <8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 0, i32 1, i32 2, i32 3>
 ; CHECK-NEXT:    [[CVTPH2PS:%.*]] = fpext <8 x half> [[TMP2]] to <8 x float>
 ; CHECK-NEXT:    ret <8 x float> [[CVTPH2PS]]
 ;

llvm/test/Transforms/InstCombine/cast.ll

@@ -858,11 +858,11 @@ define i64 @test59(i8 %A, i8 %B) {
 
 define <3 x i32> @test60(<4 x i32> %call4) {
 ; BE-LABEL: @test60(
-; BE-NEXT:    [[P10:%.*]] = shufflevector <4 x i32> [[CALL4:%.*]], <4 x i32> undef, <3 x i32> <i32 1, i32 2, i32 3>
+; BE-NEXT:    [[P10:%.*]] = shufflevector <4 x i32> [[CALL4:%.*]], <4 x i32> poison, <3 x i32> <i32 1, i32 2, i32 3>
 ; BE-NEXT:    ret <3 x i32> [[P10]]
 ;
 ; LE-LABEL: @test60(
-; LE-NEXT:    [[P10:%.*]] = shufflevector <4 x i32> [[CALL4:%.*]], <4 x i32> undef, <3 x i32> <i32 0, i32 1, i32 2>
+; LE-NEXT:    [[P10:%.*]] = shufflevector <4 x i32> [[CALL4:%.*]], <4 x i32> poison, <3 x i32> <i32 0, i32 1, i32 2>
 ; LE-NEXT:    ret <3 x i32> [[P10]]
 ;
   %p11 = bitcast <4 x i32> %call4 to i128

llvm/test/Transforms/InstCombine/shuffle-cast-dist.ll

@@ -5,7 +5,7 @@ define <2 x float> @vtrn1(<2 x i32> %v)
 ; CHECK-LABEL: @vtrn1(
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    [[TMP0:%.*]] = bitcast <2 x i32> [[V:%.*]] to <2 x float>
-; CHECK-NEXT:    [[R:%.*]] = shufflevector <2 x float> [[TMP0]], <2 x float> undef, <2 x i32> zeroinitializer
+; CHECK-NEXT:    [[R:%.*]] = shufflevector <2 x float> [[TMP0]], <2 x float> poison, <2 x i32> zeroinitializer
 ; CHECK-NEXT:    ret <2 x float> [[R]]
 ;
 {

llvm/test/Transforms/InstCombine/shufflevec-bitcast-inseltpoison.ll

@@ -57,7 +57,7 @@ define <4 x i16> @splat_bitcast_operand_uses(<8 x i8> %x) {
 define <4 x i32> @splat_bitcast_operand_same_size_src_elt(<4 x float> %x) {
 ; CHECK-LABEL: @splat_bitcast_operand_same_size_src_elt(
 ; CHECK-NEXT:    [[TMP1:%.*]] = bitcast <4 x float> [[X:%.*]] to <4 x i32>
-; CHECK-NEXT:    [[BC:%.*]] = shufflevector <4 x i32> [[TMP1]], <4 x i32> undef, <4 x i32> <i32 2, i32 2, i32 2, i32 2>
+; CHECK-NEXT:    [[BC:%.*]] = shufflevector <4 x i32> [[TMP1]], <4 x i32> poison, <4 x i32> <i32 2, i32 2, i32 2, i32 2>
 ; CHECK-NEXT:    ret <4 x i32> [[BC]]
 ;
   %s1 = shufflevector <4 x float> %x, <4 x float> poison, <4 x i32> <i32 2, i32 2, i32 2, i32 2>

llvm/test/Transforms/InstCombine/shufflevec-bitcast.ll

@@ -57,7 +57,7 @@ define <4 x i16> @splat_bitcast_operand_uses(<8 x i8> %x) {
 define <4 x i32> @splat_bitcast_operand_same_size_src_elt(<4 x float> %x) {
 ; CHECK-LABEL: @splat_bitcast_operand_same_size_src_elt(
 ; CHECK-NEXT:    [[TMP1:%.*]] = bitcast <4 x float> [[X:%.*]] to <4 x i32>
-; CHECK-NEXT:    [[BC:%.*]] = shufflevector <4 x i32> [[TMP1]], <4 x i32> undef, <4 x i32> <i32 2, i32 2, i32 2, i32 2>
+; CHECK-NEXT:    [[BC:%.*]] = shufflevector <4 x i32> [[TMP1]], <4 x i32> poison, <4 x i32> <i32 2, i32 2, i32 2, i32 2>
 ; CHECK-NEXT:    ret <4 x i32> [[BC]]
 ;
   %s1 = shufflevector <4 x float> %x, <4 x float> undef, <4 x i32> <i32 2, i32 2, i32 2, i32 2>

llvm/test/Transforms/InstCombine/trunc-inseltpoison.ll

@@ -922,7 +922,7 @@ define <4 x i8> @wide_shuf(<4 x i32> %x) {
 define <4 x i8> @wide_splat1(<4 x i32> %x) {
 ; CHECK-LABEL: @wide_splat1(
 ; CHECK-NEXT:    [[TMP1:%.*]] = trunc <4 x i32> [[X:%.*]] to <4 x i8>
-; CHECK-NEXT:    [[TRUNC:%.*]] = shufflevector <4 x i8> [[TMP1]], <4 x i8> undef, <4 x i32> <i32 2, i32 2, i32 2, i32 2>
+; CHECK-NEXT:    [[TRUNC:%.*]] = shufflevector <4 x i8> [[TMP1]], <4 x i8> poison, <4 x i32> <i32 2, i32 2, i32 2, i32 2>
 ; CHECK-NEXT:    ret <4 x i8> [[TRUNC]]
 ;
   %shuf = shufflevector <4 x i32> %x, <4 x i32> poison, <4 x i32> <i32 2, i32 2, i32 2, i32 2>
@@ -936,7 +936,7 @@ define <4 x i8> @wide_splat1(<4 x i32> %x) {
 define <3 x i31> @wide_splat2(<3 x i33> %x) {
 ; CHECK-LABEL: @wide_splat2(
 ; CHECK-NEXT:    [[TMP1:%.*]] = trunc <3 x i33> [[X:%.*]] to <3 x i31>
-; CHECK-NEXT:    [[TRUNC:%.*]] = shufflevector <3 x i31> [[TMP1]], <3 x i31> undef, <3 x i32> <i32 1, i32 1, i32 1>
+; CHECK-NEXT:    [[TRUNC:%.*]] = shufflevector <3 x i31> [[TMP1]], <3 x i31> poison, <3 x i32> <i32 1, i32 1, i32 1>
 ; CHECK-NEXT:    ret <3 x i31> [[TRUNC]]
 ;
   %shuf = shufflevector <3 x i33> %x, <3 x i33> poison, <3 x i32> <i32 1, i32 1, i32 1>

llvm/test/Transforms/InstCombine/trunc.ll

@@ -922,7 +922,7 @@ define <4 x i8> @wide_shuf(<4 x i32> %x) {
 define <4 x i8> @wide_splat1(<4 x i32> %x) {
 ; CHECK-LABEL: @wide_splat1(
 ; CHECK-NEXT:    [[TMP1:%.*]] = trunc <4 x i32> [[X:%.*]] to <4 x i8>
-; CHECK-NEXT:    [[TRUNC:%.*]] = shufflevector <4 x i8> [[TMP1]], <4 x i8> undef, <4 x i32> <i32 2, i32 2, i32 2, i32 2>
+; CHECK-NEXT:    [[TRUNC:%.*]] = shufflevector <4 x i8> [[TMP1]], <4 x i8> poison, <4 x i32> <i32 2, i32 2, i32 2, i32 2>
 ; CHECK-NEXT:    ret <4 x i8> [[TRUNC]]
 ;
   %shuf = shufflevector <4 x i32> %x, <4 x i32> undef, <4 x i32> <i32 2, i32 2, i32 2, i32 2>
@@ -936,7 +936,7 @@ define <4 x i8> @wide_splat1(<4 x i32> %x) {
 define <3 x i31> @wide_splat2(<3 x i33> %x) {
 ; CHECK-LABEL: @wide_splat2(
 ; CHECK-NEXT:    [[TMP1:%.*]] = trunc <3 x i33> [[X:%.*]] to <3 x i31>
-; CHECK-NEXT:    [[TRUNC:%.*]] = shufflevector <3 x i31> [[TMP1]], <3 x i31> undef, <3 x i32> <i32 1, i32 1, i32 1>
+; CHECK-NEXT:    [[TRUNC:%.*]] = shufflevector <3 x i31> [[TMP1]], <3 x i31> poison, <3 x i32> <i32 1, i32 1, i32 1>
 ; CHECK-NEXT:    ret <3 x i31> [[TRUNC]]
 ;
   %shuf = shufflevector <3 x i33> %x, <3 x i33> undef, <3 x i32> <i32 1, i32 1, i32 1>

llvm/test/Transforms/InstCombine/vector-casts.ll

@@ -414,7 +414,7 @@ define <2 x i64> @zext_less_casting_with_wideop(<2 x i64> %x, <2 x i64> %y) {
 define <4 x float> @sitofp_shuf(<4 x i32> %x) {
 ; CHECK-LABEL: @sitofp_shuf(
 ; CHECK-NEXT:    [[TMP1:%.*]] = sitofp <4 x i32> [[X:%.*]] to <4 x float>
-; CHECK-NEXT:    [[R:%.*]] = shufflevector <4 x float> [[TMP1]], <4 x float> undef, <4 x i32> <i32 1, i32 2, i32 3, i32 undef>
+; CHECK-NEXT:    [[R:%.*]] = shufflevector <4 x float> [[TMP1]], <4 x float> poison, <4 x i32> <i32 1, i32 2, i32 3, i32 undef>
 ; CHECK-NEXT:    ret <4 x float> [[R]]
 ;
   %s = shufflevector <4 x i32> %x, <4 x i32> poison, <4 x i32> <i32 1, i32 2, i32 3, i32 undef>
@@ -425,7 +425,7 @@ define <4 x float> @sitofp_shuf(<4 x i32> %x) {
 define <3 x half> @uitofp_shuf(<3 x i16> %x) {
 ; CHECK-LABEL: @uitofp_shuf(
 ; CHECK-NEXT:    [[TMP1:%.*]] = uitofp <3 x i16> [[X:%.*]] to <3 x half>
-; CHECK-NEXT:    [[R:%.*]] = shufflevector <3 x half> [[TMP1]], <3 x half> undef, <3 x i32> <i32 2, i32 undef, i32 0>
+; CHECK-NEXT:    [[R:%.*]] = shufflevector <3 x half> [[TMP1]], <3 x half> poison, <3 x i32> <i32 2, i32 undef, i32 0>
 ; CHECK-NEXT:    ret <3 x half> [[R]]
 ;
   %s = shufflevector <3 x i16> %x, <3 x i16> poison, <3 x i32> <i32 2, i32 undef, i32 0>
@@ -436,7 +436,7 @@ define <3 x half> @uitofp_shuf(<3 x i16> %x) {
 define <4 x i64> @fptosi_shuf(<4 x double> %x) {
 ; CHECK-LABEL: @fptosi_shuf(
 ; CHECK-NEXT:    [[TMP1:%.*]] = fptosi <4 x double> [[X:%.*]] to <4 x i64>
-; CHECK-NEXT:    [[R:%.*]] = shufflevector <4 x i64> [[TMP1]], <4 x i64> undef, <4 x i32> <i32 undef, i32 2, i32 3, i32 undef>
+; CHECK-NEXT:    [[R:%.*]] = shufflevector <4 x i64> [[TMP1]], <4 x i64> poison, <4 x i32> <i32 undef, i32 2, i32 3, i32 undef>
 ; CHECK-NEXT:    ret <4 x i64> [[R]]
 ;
   %s = shufflevector <4 x double> %x, <4 x double> poison, <4 x i32> <i32 undef, i32 2, i32 3, i32 undef>
@@ -447,7 +447,7 @@ define <4 x i64> @fptosi_shuf(<4 x double> %x) {
 define <2 x i32> @fptoui_shuf(<2 x float> %x) {
 ; CHECK-LABEL: @fptoui_shuf(
 ; CHECK-NEXT:    [[TMP1:%.*]] = fptoui <2 x float> [[X:%.*]] to <2 x i32>
-; CHECK-NEXT:    [[R:%.*]] = shufflevector <2 x i32> [[TMP1]], <2 x i32> undef, <2 x i32> <i32 1, i32 1>
+; CHECK-NEXT:    [[R:%.*]] = shufflevector <2 x i32> [[TMP1]], <2 x i32> poison, <2 x i32> <i32 1, i32 1>
 ; CHECK-NEXT:    ret <2 x i32> [[R]]
 ;
   %s = shufflevector <2 x float> %x, <2 x float> poison, <2 x i32> <i32 1, i32 1>