[llvm] [InstCombine] Remove transformation on call instruction where return value need void to non-void conversion (PR #98536)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,24 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt --passes=instcombine -S < %s | FileCheck %s
+
+define dso_local void @foo() {
+; CHECK-LABEL: define dso_local void @foo() {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    ret void
+;
+entry:
+  ret void
+}
+
+define dso_local i32 @bar() {
+; CHECK-LABEL: define dso_local i32 @bar() {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[TMP0:%.*]] = tail call i32 @foo()
+; CHECK-NEXT:    [[TMP1:%.*]] = add i32 [[TMP0]], 1
+; CHECK-NEXT:    ret i32 [[TMP1]]
+;
+entry:
+  %1 = tail call i32 @foo()
+  %2 = add i32 %1, 1
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nikic wrote:

Can drop the add too :)

https://github.com/llvm/llvm-project/pull/98536