[llvm] ee3068b - [ConstantFolding] Fix type mismatch in ConstantFolding for vector types. (#181695)

[via llvm-commits]

Author: Marcos Maronas
Date: 2026-02-18T18:49:40Z
New Revision: ee3068bd18b23ceb30c0464395fa182cfa28a5fb

URL: https://github.com/llvm/llvm-project/commit/ee3068bd18b23ceb30c0464395fa182cfa28a5fb
DIFF: https://github.com/llvm/llvm-project/commit/ee3068bd18b23ceb30c0464395fa182cfa28a5fb.diff

LOG: [ConstantFolding] Fix type mismatch in ConstantFolding for vector types. (#181695)

Drop `Bitcast` case from `IsConstantOffsetFromGlobal` to avoid
misdetections.

Added: 
    llvm/test/Transforms/InstSimplify/ConstProp/vector-type-constant-folding.ll

Modified: 
    llvm/lib/Analysis/ConstantFolding.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Analysis/ConstantFolding.cpp b/llvm/lib/Analysis/ConstantFolding.cpp
index b0ac14ba8b393..738d0c063a5e4 100644
--- a/llvm/lib/Analysis/ConstantFolding.cpp
+++ b/llvm/lib/Analysis/ConstantFolding.cpp
@@ -329,8 +329,7 @@ bool llvm::IsConstantOffsetFromGlobal(Constant *C, GlobalValue *&GV,
 
   // Look through ptr->int and ptr->ptr casts.
   if (CE->getOpcode() == Instruction::PtrToInt ||
-      CE->getOpcode() == Instruction::PtrToAddr ||
-      CE->getOpcode() == Instruction::BitCast)
+      CE->getOpcode() == Instruction::PtrToAddr)
     return IsConstantOffsetFromGlobal(CE->getOperand(0), GV, Offset, DL,
                                       DSOEquiv);
 

diff  --git a/llvm/test/Transforms/InstSimplify/ConstProp/vector-type-constant-folding.ll b/llvm/test/Transforms/InstSimplify/ConstProp/vector-type-constant-folding.ll
new file mode 100644
index 0000000000000..5b12fd3ec545f
--- /dev/null
+++ b/llvm/test/Transforms/InstSimplify/ConstProp/vector-type-constant-folding.ll
@@ -0,0 +1,25 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
+; RUN: opt < %s -passes=instsimplify -S | FileCheck %s
+;
+; Test type mismatch in ConstantFolding for vector types.
+
+define internal void @f() {
+; CHECK-LABEL: define internal void @f() {
+; CHECK-NEXT:    ret void
+;
+  ret void
+}
+
+define void @test() {
+; CHECK-LABEL: define void @test() {
+; CHECK-NEXT:    store <4 x i16> <i16 sub (i16 extractelement (<4 x i16> bitcast (i64 ptrtoint (ptr @f to i64) to <4 x i16>), i32 0), i16 extractelement (<4 x i16> bitcast (i64 ptrtoint (ptr @f to i64) to <4 x i16>), i32 0)), i16 sub (i16 extractelement (<4 x i16> bitcast (i64 ptrtoint (ptr @f to i64) to <4 x i16>), i32 1), i16 extractelement (<4 x i16> bitcast (i64 ptrtoint (ptr @f to i64) to <4 x i16>), i32 1)), i16 sub (i16 extractelement (<4 x i16> bitcast (i64 ptrtoint (ptr @f to i64) to <4 x i16>), i32 2), i16 extractelement (<4 x i16> bitcast (i64 ptrtoint (ptr @f to i64) to <4 x i16>), i32 2)), i16 sub (i16 extractelement (<4 x i16> bitcast (i64 ptrtoint (ptr @f to i64) to <4 x i16>), i32 3), i16 extractelement (<4 x i16> bitcast (i64 ptrtoint (ptr @f to i64) to <4 x i16>), i32 3))>, ptr @f, align 8
+; CHECK-NEXT:    ret void
+;
+  %1 = ptrtoint ptr @f to i64
+  %2 = bitcast i64 %1 to <4 x i16>
+  %3 = ptrtoint ptr @f to i64
+  %4 = bitcast i64 %3 to <4 x i16>
+  %sub = sub <4 x i16> %2, %4
+  store <4 x i16> %sub, ptr @f, align 8
+  ret void
+}