[TargetLowering] Add SimplifyDemandedBits support for ISD::INSERT_VECTOR_ELT

This helps us relax the extension of a lot of scalar elements before they are inserted into a vector.

Its exposes an issue in DAGCombiner::convertBuildVecZextToZext as some/all the zero-extensions may be relaxed to ANY_EXTEND, so we need to handle that case to avoid a couple of AVX2 VPMOVZX test regressions.

Once this is in it should be easier to fix a number of remaining failures to fold loads into VBROADCAST nodes.

Differential Revision: https://reviews.llvm.org/D59484

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@356989 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 5d7ed8ab5c3dd89779e98862e7a8f186f09cfb96..d6b2b5b06b1e6af742bef68fb4cfb9ffe8c8d0f8 100644 (file)
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -16824,7 +16824,7 @@ SDValue DAGCombiner::reduceBuildVecToShuffle(SDNode *N) {
 
 // Try to turn a build vector of zero extends of extract vector elts into a
 // a vector zero extend and possibly an extract subvector.
-// TODO: Support sign extend or any extend?
+// TODO: Support sign extend?
 // TODO: Allow undef elements?
 SDValue DAGCombiner::convertBuildVecZextToZext(SDNode *N) {
   if (LegalOperations)
@@ -16832,9 +16832,12 @@ SDValue DAGCombiner::convertBuildVecZextToZext(SDNode *N) {
 
   EVT VT = N->getValueType(0);
 
+  bool FoundZeroExtend = false;
   SDValue Op0 = N->getOperand(0);
   auto checkElem = [&](SDValue Op) -> int64_t {
-    if (Op.getOpcode() == ISD::ZERO_EXTEND &&
+    unsigned Opc = Op.getOpcode();
+    FoundZeroExtend |= (Opc == ISD::ZERO_EXTEND);
+    if ((Op.getOpcode() == ISD::ZERO_EXTEND || Opc == ISD::ANY_EXTEND) &&
         Op.getOperand(0).getOpcode() == ISD::EXTRACT_VECTOR_ELT &&
         Op0.getOperand(0).getOperand(0) == Op.getOperand(0).getOperand(0))
       if (auto *C = dyn_cast<ConstantSDNode>(Op.getOperand(0).getOperand(1)))
@@ -16866,7 +16869,8 @@ SDValue DAGCombiner::convertBuildVecZextToZext(SDNode *N) {
   SDLoc DL(N);
   In = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, InVT, In,
                    Op0.getOperand(0).getOperand(1));
-  return DAG.getNode(ISD::ZERO_EXTEND, DL, VT, In);
+  return DAG.getNode(FoundZeroExtend ? ISD::ZERO_EXTEND : ISD::ANY_EXTEND, DL,
+                     VT, In);
 }
 
 SDValue DAGCombiner::visitBUILD_VECTOR(SDNode *N) {

diff --git a/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/lib/CodeGen/SelectionDAG/TargetLowering.cpp
index 5ebbd93a4327e4399e64b55d95a080c21bf03a8c..8796888c7e5012168caddf2ce5993ab98ffcc4ea 100644 (file)
--- a/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -557,6 +557,44 @@ bool TargetLowering::SimplifyDemandedBits(
       Known.Zero &= Known2.Zero;
     }
     return false; // Don't fall through, will infinitely loop.
+  case ISD::INSERT_VECTOR_ELT: {
+    SDValue Vec = Op.getOperand(0);
+    SDValue Scl = Op.getOperand(1);
+    auto *CIdx = dyn_cast<ConstantSDNode>(Op.getOperand(2));
+    EVT VecVT = Vec.getValueType();
+
+    // If index isn't constant, assume we need all vector elements AND the
+    // inserted element.
+    APInt DemandedVecElts(OriginalDemandedElts);
+    if (CIdx && CIdx->getAPIntValue().ult(VecVT.getVectorNumElements())) {
+      unsigned Idx = CIdx->getZExtValue();
+      DemandedVecElts.clearBit(Idx);
+
+      // Inserted element is not required.
+      if (!OriginalDemandedElts[Idx])
+        return TLO.CombineTo(Op, Vec);
+    }
+
+    KnownBits KnownScl;
+    unsigned NumSclBits = Scl.getScalarValueSizeInBits();
+    APInt DemandedSclBits = OriginalDemandedBits.zextOrTrunc(NumSclBits);
+    if (SimplifyDemandedBits(Scl, DemandedSclBits, KnownScl, TLO, Depth + 1))
+      return true;
+
+    Known = KnownScl.zextOrTrunc(BitWidth, false);
+
+    KnownBits KnownVec;
+    if (SimplifyDemandedBits(Vec, OriginalDemandedBits, DemandedVecElts,
+                             KnownVec, TLO, Depth + 1))
+      return true;
+
+    if (!!DemandedVecElts) {
+      Known.One &= KnownVec.One;
+      Known.Zero &= KnownVec.Zero;
+    }
+
+    return false;
+  }
   case ISD::CONCAT_VECTORS: {
     Known.Zero.setAllBits();
     Known.One.setAllBits();

diff --git a/test/CodeGen/X86/known-signbits-vector.ll b/test/CodeGen/X86/known-signbits-vector.ll
index d2135a6a3bb70928814828707528e7f99ff98378..0e6c067c159c1359c44a3d02adfaf586891d9f29 100644 (file)
--- a/test/CodeGen/X86/known-signbits-vector.ll
+++ b/test/CodeGen/X86/known-signbits-vector.ll
@@ -144,9 +144,9 @@ define float @signbits_ashr_insert_ashr_extract_sitofp(i64 %a0, i64 %a1) nounwin
 ; X32:       # %bb.0:
 ; X32-NEXT:    pushl %eax
 ; X32-NEXT:    movl {{[0-9]+}}(%esp), %eax
-; X32-NEXT:    movl {{[0-9]+}}(%esp), %ecx
-; X32-NEXT:    shrdl $30, %ecx, %eax
+; X32-NEXT:    movl %eax, %ecx
 ; X32-NEXT:    sarl $30, %ecx
+; X32-NEXT:    shll $2, %eax
 ; X32-NEXT:    vmovd %eax, %xmm0
 ; X32-NEXT:    vpinsrd $1, %ecx, %xmm0, %xmm0
 ; X32-NEXT:    vpsrlq $3, %xmm0, %xmm0

diff --git a/test/CodeGen/X86/mulvi32.ll b/test/CodeGen/X86/mulvi32.ll
index fc185d18044733ddaca90b3687344f5bbceb1096..550bc60399d9292d6884e02cf820f92e986c40f1 100644 (file)
--- a/test/CodeGen/X86/mulvi32.ll
+++ b/test/CodeGen/X86/mulvi32.ll
@@ -312,18 +312,10 @@ define <4 x i64> @_mul4xi32toi64c(<4 x i32>, <4 x i32>) {
 ; %ext0 = zext <2 x i32> %0 to <2 x i64>
 ; %ext1 = zext <2 x i32> %1 to <2 x i64>
 define <2 x i64> @_mul2xi64toi64a(<2 x i64>, <2 x i64>) {
-; SSE2-LABEL: _mul2xi64toi64a:
-; SSE2:       # %bb.0:
-; SSE2-NEXT:    movdqa {{.*#+}} xmm2 = [4294967295,4294967295]
-; SSE2-NEXT:    pand %xmm2, %xmm0
-; SSE2-NEXT:    pand %xmm2, %xmm1
-; SSE2-NEXT:    pmuludq %xmm1, %xmm0
-; SSE2-NEXT:    retq
-;
-; SSE42-LABEL: _mul2xi64toi64a:
-; SSE42:       # %bb.0:
-; SSE42-NEXT:    pmuludq %xmm1, %xmm0
-; SSE42-NEXT:    retq
+; SSE-LABEL: _mul2xi64toi64a:
+; SSE:       # %bb.0:
+; SSE-NEXT:    pmuludq %xmm1, %xmm0
+; SSE-NEXT:    retq
 ;
 ; AVX-LABEL: _mul2xi64toi64a:
 ; AVX:       # %bb.0:

diff --git a/test/CodeGen/X86/vector-shuffle-128-v16.ll b/test/CodeGen/X86/vector-shuffle-128-v16.ll
index 20a8095be4c55c902d4f56426eab6ffbf35fbd2c..1a2851e465ed5f76f9c66101f4b050e63136e3ad 100644 (file)
--- a/test/CodeGen/X86/vector-shuffle-128-v16.ll
+++ b/test/CodeGen/X86/vector-shuffle-128-v16.ll
@@ -1736,7 +1736,7 @@ define <16 x i8> @insert_dup_mem_v16i8_i32(i32* %ptr) {
 define <16 x i8> @insert_dup_mem_v16i8_sext_i8(i8* %ptr) {
 ; SSE2-LABEL: insert_dup_mem_v16i8_sext_i8:
 ; SSE2:       # %bb.0:
-; SSE2-NEXT:    movsbl (%rdi), %eax
+; SSE2-NEXT:    movzbl (%rdi), %eax
 ; SSE2-NEXT:    movd %eax, %xmm0
 ; SSE2-NEXT:    punpcklbw {{.*#+}} xmm0 = xmm0[0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7]
 ; SSE2-NEXT:    pshuflw {{.*#+}} xmm0 = xmm0[0,0,2,3,4,5,6,7]
@@ -1745,7 +1745,7 @@ define <16 x i8> @insert_dup_mem_v16i8_sext_i8(i8* %ptr) {
 ;
 ; SSSE3-LABEL: insert_dup_mem_v16i8_sext_i8:
 ; SSSE3:       # %bb.0:
-; SSSE3-NEXT:    movsbl (%rdi), %eax
+; SSSE3-NEXT:    movzbl (%rdi), %eax
 ; SSSE3-NEXT:    movd %eax, %xmm0
 ; SSSE3-NEXT:    pxor %xmm1, %xmm1
 ; SSSE3-NEXT:    pshufb %xmm1, %xmm0
@@ -1753,7 +1753,7 @@ define <16 x i8> @insert_dup_mem_v16i8_sext_i8(i8* %ptr) {
 ;
 ; SSE41-LABEL: insert_dup_mem_v16i8_sext_i8:
 ; SSE41:       # %bb.0:
-; SSE41-NEXT:    movsbl (%rdi), %eax
+; SSE41-NEXT:    movzbl (%rdi), %eax
 ; SSE41-NEXT:    movd %eax, %xmm0
 ; SSE41-NEXT:    pxor %xmm1, %xmm1
 ; SSE41-NEXT:    pshufb %xmm1, %xmm0
@@ -1761,7 +1761,7 @@ define <16 x i8> @insert_dup_mem_v16i8_sext_i8(i8* %ptr) {
 ;
 ; AVX1-LABEL: insert_dup_mem_v16i8_sext_i8:
 ; AVX1:       # %bb.0:
-; AVX1-NEXT:    movsbl (%rdi), %eax
+; AVX1-NEXT:    movzbl (%rdi), %eax
 ; AVX1-NEXT:    vmovd %eax, %xmm0
 ; AVX1-NEXT:    vpxor %xmm1, %xmm1, %xmm1
 ; AVX1-NEXT:    vpshufb %xmm1, %xmm0, %xmm0

diff --git a/test/CodeGen/X86/vector-shuffle-128-v8.ll b/test/CodeGen/X86/vector-shuffle-128-v8.ll
index d74aac174b3cb32a5e2f2102ffcd5858dcd785d0..020354bbd84508292ad7c7a4c37ab813142cbf19 100644 (file)
--- a/test/CodeGen/X86/vector-shuffle-128-v8.ll
+++ b/test/CodeGen/X86/vector-shuffle-128-v8.ll
@@ -2652,7 +2652,7 @@ define <8 x i16> @insert_dup_mem_v8i16_i32(i32* %ptr) {
 define <8 x i16> @insert_dup_mem_v8i16_sext_i16(i16* %ptr) {
 ; SSE-LABEL: insert_dup_mem_v8i16_sext_i16:
 ; SSE:       # %bb.0:
-; SSE-NEXT:    movswl (%rdi), %eax
+; SSE-NEXT:    movzwl (%rdi), %eax
 ; SSE-NEXT:    movd %eax, %xmm0
 ; SSE-NEXT:    pshuflw {{.*#+}} xmm0 = xmm0[0,0,2,3,4,5,6,7]
 ; SSE-NEXT:    pshufd {{.*#+}} xmm0 = xmm0[0,0,0,0]
@@ -2660,7 +2660,7 @@ define <8 x i16> @insert_dup_mem_v8i16_sext_i16(i16* %ptr) {
 ;
 ; AVX1-LABEL: insert_dup_mem_v8i16_sext_i16:
 ; AVX1:       # %bb.0:
-; AVX1-NEXT:    movswl (%rdi), %eax
+; AVX1-NEXT:    movzwl (%rdi), %eax
 ; AVX1-NEXT:    vmovd %eax, %xmm0
 ; AVX1-NEXT:    vpshuflw {{.*#+}} xmm0 = xmm0[0,0,2,3,4,5,6,7]
 ; AVX1-NEXT:    vpshufd {{.*#+}} xmm0 = xmm0[0,0,0,0]
@@ -2668,14 +2668,14 @@ define <8 x i16> @insert_dup_mem_v8i16_sext_i16(i16* %ptr) {
 ;
 ; AVX2-LABEL: insert_dup_mem_v8i16_sext_i16:
 ; AVX2:       # %bb.0:
-; AVX2-NEXT:    movswl (%rdi), %eax
+; AVX2-NEXT:    movzwl (%rdi), %eax
 ; AVX2-NEXT:    vmovd %eax, %xmm0
 ; AVX2-NEXT:    vpbroadcastw %xmm0, %xmm0
 ; AVX2-NEXT:    retq
 ;
 ; AVX512VL-LABEL: insert_dup_mem_v8i16_sext_i16:
 ; AVX512VL:       # %bb.0:
-; AVX512VL-NEXT:    movswl (%rdi), %eax
+; AVX512VL-NEXT:    movzwl (%rdi), %eax
 ; AVX512VL-NEXT:    vpbroadcastw %eax, %xmm0
 ; AVX512VL-NEXT:    retq
   %tmp = load i16, i16* %ptr, align 2

diff --git a/test/CodeGen/X86/vector-shuffle-256-v16.ll b/test/CodeGen/X86/vector-shuffle-256-v16.ll
index 7b093062f41f05b0761a26e2bd41b8223bcd1687..7d2b6c8a35d0e02611067b08b27069c4a831605a 100644 (file)
--- a/test/CodeGen/X86/vector-shuffle-256-v16.ll
+++ b/test/CodeGen/X86/vector-shuffle-256-v16.ll
@@ -4722,7 +4722,7 @@ define <16 x i16> @insert_dup_mem_v16i16_i32(i32* %ptr) {
 define <16 x i16> @insert_dup_mem_v16i16_sext_i16(i16* %ptr) {
 ; AVX1-LABEL: insert_dup_mem_v16i16_sext_i16:
 ; AVX1:       # %bb.0:
-; AVX1-NEXT:    movswl (%rdi), %eax
+; AVX1-NEXT:    movzwl (%rdi), %eax
 ; AVX1-NEXT:    vmovd %eax, %xmm0
 ; AVX1-NEXT:    vpshuflw {{.*#+}} xmm0 = xmm0[0,0,2,3,4,5,6,7]
 ; AVX1-NEXT:    vpshufd {{.*#+}} xmm0 = xmm0[0,0,0,0]
@@ -4731,14 +4731,14 @@ define <16 x i16> @insert_dup_mem_v16i16_sext_i16(i16* %ptr) {
 ;
 ; AVX2-LABEL: insert_dup_mem_v16i16_sext_i16:
 ; AVX2:       # %bb.0:
-; AVX2-NEXT:    movswl (%rdi), %eax
+; AVX2-NEXT:    movzwl (%rdi), %eax
 ; AVX2-NEXT:    vmovd %eax, %xmm0
 ; AVX2-NEXT:    vpbroadcastw %xmm0, %ymm0
 ; AVX2-NEXT:    retq
 ;
 ; AVX512VL-LABEL: insert_dup_mem_v16i16_sext_i16:
 ; AVX512VL:       # %bb.0:
-; AVX512VL-NEXT:    movswl (%rdi), %eax
+; AVX512VL-NEXT:    movzwl (%rdi), %eax
 ; AVX512VL-NEXT:    vpbroadcastw %eax, %ymm0
 ; AVX512VL-NEXT:    retq
   %tmp = load i16, i16* %ptr, align 2

diff --git a/test/CodeGen/X86/vector-shuffle-256-v32.ll b/test/CodeGen/X86/vector-shuffle-256-v32.ll
index e0c3a51db250f3f51714db726b668999666546a0..16cbb1a8903f60233a372641cc11110f2195a059 100644 (file)
--- a/test/CodeGen/X86/vector-shuffle-256-v32.ll
+++ b/test/CodeGen/X86/vector-shuffle-256-v32.ll
@@ -3154,7 +3154,7 @@ define <32 x i8> @insert_dup_mem_v32i8_i32(i32* %ptr) {
 define <32 x i8> @insert_dup_mem_v32i8_sext_i8(i8* %ptr) {
 ; AVX1-LABEL: insert_dup_mem_v32i8_sext_i8:
 ; AVX1:       # %bb.0:
-; AVX1-NEXT:    movsbl (%rdi), %eax
+; AVX1-NEXT:    movzbl (%rdi), %eax
 ; AVX1-NEXT:    vmovd %eax, %xmm0
 ; AVX1-NEXT:    vpxor %xmm1, %xmm1, %xmm1
 ; AVX1-NEXT:    vpshufb %xmm1, %xmm0, %xmm0

diff --git a/test/CodeGen/X86/vector-shuffle-512-v32.ll b/test/CodeGen/X86/vector-shuffle-512-v32.ll
index d27bcfc85c356660a5fffc13d5d6de692a72f483..d9a0ab539aa3dedb27f2fae0c1c5e3e874150615 100644 (file)
--- a/test/CodeGen/X86/vector-shuffle-512-v32.ll
+++ b/test/CodeGen/X86/vector-shuffle-512-v32.ll
@@ -233,7 +233,7 @@ define <32 x i16> @insert_dup_mem_v32i16_i32(i32* %ptr) {
 define <32 x i16> @insert_dup_mem_v32i16_sext_i16(i16* %ptr) {
 ; KNL-LABEL: insert_dup_mem_v32i16_sext_i16:
 ; KNL:       ## %bb.0:
-; KNL-NEXT:    movswl (%rdi), %eax
+; KNL-NEXT:    movzwl (%rdi), %eax
 ; KNL-NEXT:    vmovd %eax, %xmm0
 ; KNL-NEXT:    vpbroadcastw %xmm0, %ymm0
 ; KNL-NEXT:    vmovdqa %ymm0, %ymm1
@@ -241,7 +241,7 @@ define <32 x i16> @insert_dup_mem_v32i16_sext_i16(i16* %ptr) {
 ;
 ; SKX-LABEL: insert_dup_mem_v32i16_sext_i16:
 ; SKX:       ## %bb.0:
-; SKX-NEXT:    movswl (%rdi), %eax
+; SKX-NEXT:    movzwl (%rdi), %eax
 ; SKX-NEXT:    vpbroadcastw %eax, %zmm0
 ; SKX-NEXT:    retq
   %tmp = load i16, i16* %ptr, align 2