[llvm] [GlobalOpt] add support for CallInst and InvokeInst users (PR #221955)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,21 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
+; RUN: opt -S -passes=globalopt < %s | FileCheck %s
+
+ at g0 = internal global ptr null, align 8
+ at g30 = internal global ptr @g0, align 8
+
+declare void @g21()
+declare void @llvm.memmove.p0.p0.i64(ptr, ptr, i64, i1)
+
+define i32 @main() {
+; CHECK-LABEL: define i32 @main() local_unnamed_addr {
+; CHECK-NEXT:    store ptr @g21, ptr @g0, align 8
+; CHECK-NEXT:    call void @llvm.memmove.p0.p0.i64(ptr null, ptr @g0, i64 0, i1 false)
+; CHECK-NEXT:    ret i32 0
+;
+  store ptr @g21, ptr @g0, align 8
+  %v = load ptr, ptr @g30, align 8
+  call void @llvm.memmove.p0.p0.i64(ptr null, ptr %v, i64 0, i1 false)
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nikic wrote:

Replace null with a pointer argument to avoid UB.

https://github.com/llvm/llvm-project/pull/221955