[SDAG][X86] Extend SplitVecOp_VSETCC for STRICT_FSETCC.

[FreddyLeaf]

No description provided.

[llvmbot]

@llvm/pr-subscribers-backend-x86

@llvm/pr-subscribers-llvm-selectiondag

Author: Freddy Ye (FreddyLeaf)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/92509.diff

2 Files Affected:

• (modified) llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp (+16-3)
• (added) llvm/test/CodeGen/X86/vec-strict-cmp-512-skx.ll (+22)

diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
index cd858003cf03b..6ddb6dc4dd871 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
@@ -3033,6 +3033,7 @@ bool DAGTypeLegalizer::SplitVectorOperand(SDNode *N, unsigned OpNo) {
                        "operand!\n");
 
   case ISD::VP_SETCC:
+  case ISD::STRICT_FSETCC:
   case ISD::SETCC:             Res = SplitVecOp_VSETCC(N); break;
   case ISD::BITCAST:           Res = SplitVecOp_BITCAST(N); break;
   case ISD::EXTRACT_SUBVECTOR: Res = SplitVecOp_EXTRACT_SUBVECTOR(N); break;
@@ -3997,14 +3998,16 @@ SDValue DAGTypeLegalizer::SplitVecOp_TruncateHelper(SDNode *N) {
 }
 
 SDValue DAGTypeLegalizer::SplitVecOp_VSETCC(SDNode *N) {
+  bool isStrict = N->getOperand(N->getOpcode() == ISD::STRICT_FSETCC;
   assert(N->getValueType(0).isVector() &&
-         N->getOperand(0).getValueType().isVector() &&
+         N->getOperand(isStrict ? 1 : 0).getValueType().isVector() &&
          "Operand types must be vectors");
   // The result has a legal vector type, but the input needs splitting.
   SDValue Lo0, Hi0, Lo1, Hi1, LoRes, HiRes;
   SDLoc DL(N);
-  GetSplitVector(N->getOperand(0), Lo0, Hi0);
-  GetSplitVector(N->getOperand(1), Lo1, Hi1);
+  GetSplitVector(N->getOperand(isStrict ? 1 : 0), Lo0, Hi0);
+  GetSplitVector(N->getOperand(isStrict ? 2 : 1), Lo1, Hi1);
+
   auto PartEltCnt = Lo0.getValueType().getVectorElementCount();
 
   LLVMContext &Context = *DAG.getContext();
@@ -4014,6 +4017,16 @@ SDValue DAGTypeLegalizer::SplitVecOp_VSETCC(SDNode *N) {
   if (N->getOpcode() == ISD::SETCC) {
     LoRes = DAG.getNode(ISD::SETCC, DL, PartResVT, Lo0, Lo1, N->getOperand(2));
     HiRes = DAG.getNode(ISD::SETCC, DL, PartResVT, Hi0, Hi1, N->getOperand(2));
+  } else if (N->getOpcode() == ISD::STRICT_FSETCC) {
+    LoRes = DAG.getNode(ISD::STRICT_FSETCC, DL,
+                        DAG.getVTList(PartResVT, N->getValueType(1)),
+                        N->getOperand(0), Lo0, Lo1, N->getOperand(3));
+    HiRes = DAG.getNode(ISD::STRICT_FSETCC, DL,
+                        DAG.getVTList(PartResVT, N->getValueType(1)),
+                        N->getOperand(0), Hi0, Hi1, N->getOperand(3));
+    SDValue NewChain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other,
+                                   LoRes.getValue(1), HiRes.getValue(1));
+    ReplaceValueWith(SDValue(N, 1), NewChain);
   } else {
     assert(N->getOpcode() == ISD::VP_SETCC && "Expected VP_SETCC opcode");
     SDValue MaskLo, MaskHi, EVLLo, EVLHi;
diff --git a/llvm/test/CodeGen/X86/vec-strict-cmp-512-skx.ll b/llvm/test/CodeGen/X86/vec-strict-cmp-512-skx.ll
new file mode 100644
index 0000000000000..ccb0cd564ed1f
--- /dev/null
+++ b/llvm/test/CodeGen/X86/vec-strict-cmp-512-skx.ll
@@ -0,0 +1,22 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mtriple=x86_64 -mcpu=skx | FileCheck %s --check-prefixes=SKX
+
+; Test not crash for 512 targets but not prefer 512 vector width
+define <16 x i32> @test_v16f32_oeq_q(<16 x i32> %a, <16 x i32> %b, <16 x float> %f1, <16 x float> %f2) #0 {
+; SKX-LABEL: test_v16f32_oeq_q:
+; SKX:       # %bb.0:
+; SKX-NEXT:    vcmpeqps %ymm7, %ymm5, %k1
+; SKX-NEXT:    vcmpeqps %ymm6, %ymm4, %k2
+; SKX-NEXT:    vpblendmd %ymm0, %ymm2, %ymm0 {%k2}
+; SKX-NEXT:    vpblendmd %ymm1, %ymm3, %ymm1 {%k1}
+; SKX-NEXT:    retq
+  %cond = call <16 x i1> @llvm.experimental.constrained.fcmp.v16f32(
+                                               <16 x float> %f1, <16 x float> %f2, metadata !"oeq",
+                                               metadata !"fpexcept.strict") #0
+  %res = select <16 x i1> %cond, <16 x i32> %a, <16 x i32> %b
+  ret <16 x i32> %res
+}
+
+declare <16 x i1> @llvm.experimental.constrained.fcmp.v16f32(<16 x float>, <16 x float>, metadata, metadata)
+
+attributes #0 = { nounwind strictfp "min-legal-vector-width"="0" }

[arsenm]

Comment grammar

[FreddyLeaf]

7ff5d8d

[arsenm]

Test more vector types

[FreddyLeaf]

7ff5d8d

[FreddyLeaf]

This patch is to fix below backend crash:
https://gcc.godbolt.org/z/7cbTx7r1T

[RKSimon]

LGTM

[KanRobert]

LGTM