release/18.x: [RISCV][ISel] Fix types in tryFoldSelectIntoOp (#90659)

[llvmbot]

Backport 2647bd7

Requested by: @dtcxzyw

[llvmbot]

@topperc What do you think about merging this PR to the release branch?

[llvmbot]

@llvm/pr-subscribers-backend-risc-v

Author: None (llvmbot)

Changes

Backport 2647bd7

Requested by: @dtcxzyw

---

Full diff: https://github.com/llvm/llvm-project/pull/90682.diff

2 Files Affected:

• (modified) llvm/lib/Target/RISCV/RISCVISelLowering.cpp (+1-1)
• (added) llvm/test/CodeGen/RISCV/pr90652.ll (+19)

diff --git a/llvm/lib/Target/RISCV/RISCVISelLowering.cpp b/llvm/lib/Target/RISCV/RISCVISelLowering.cpp
index a0cec426002b6f..d46093b9e260a2 100644
--- a/llvm/lib/Target/RISCV/RISCVISelLowering.cpp
+++ b/llvm/lib/Target/RISCV/RISCVISelLowering.cpp
@@ -14559,7 +14559,7 @@ static SDValue tryFoldSelectIntoOp(SDNode *N, SelectionDAG &DAG,
   EVT VT = N->getValueType(0);
   SDLoc DL(N);
   SDValue OtherOp = TrueVal.getOperand(1 - OpToFold);
-  EVT OtherOpVT = OtherOp->getValueType(0);
+  EVT OtherOpVT = OtherOp.getValueType();
   SDValue IdentityOperand =
       DAG.getNeutralElement(Opc, DL, OtherOpVT, N->getFlags());
   if (!Commutative)
diff --git a/llvm/test/CodeGen/RISCV/pr90652.ll b/llvm/test/CodeGen/RISCV/pr90652.ll
new file mode 100644
index 00000000000000..2162395b92ac3c
--- /dev/null
+++ b/llvm/test/CodeGen/RISCV/pr90652.ll
@@ -0,0 +1,19 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4
+; RUN: llc < %s -mtriple=riscv64 | FileCheck %s
+
+define i1 @test(i64 %x, i1 %cond1, i1 %cond2) {
+; CHECK-LABEL: test:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    addi a3, a0, 1
+; CHECK-NEXT:    slt a0, a3, a0
+; CHECK-NEXT:    not a1, a1
+; CHECK-NEXT:    and a0, a1, a0
+; CHECK-NEXT:    or a0, a2, a0
+; CHECK-NEXT:    ret
+entry:
+  %sadd = call { i64, i1 } @llvm.sadd.with.overflow.i64(i64 %x, i64 1)
+  %ov = extractvalue { i64, i1 } %sadd, 1
+  %or = or i1 %cond2, %ov
+  %sel = select i1 %cond1, i1 %cond2, i1 %or
+  ret i1 %sel
+}

[topperc]

LGTM

[tstellar]

Hi @dtcxzyw (or anyone else). If you would like to add a note about this fix in the release notes (completely optional). Please reply to this comment with a one or two sentence description of the fix. When you are done, please add the release:note label to this PR.

[dtcxzyw]

Fixed an incorrect type inference during RISC-V instruction selection, which causes an assertion failure when trying to fold selects into their operands.