Imported Upstream version 5.18.0.179

Former-commit-id: 67aa10e65b237e1c4537630979ee99ebe1374215

external/llvm/test/Transforms/DeadArgElim/2008-06-23-DeadAfterLive.ll

@@ -0,0 +1,23 @@
+; RUN: opt < %s -deadargelim -die -S > %t
+; RUN: cat %t | grep 123
+
+; This test tries to catch wrongful removal of return values for a specific case
+; that was breaking llvm-gcc builds.
+
+; This function has a live return value, it is used by @alive.
+define internal i32 @test5() {
+  ret i32 123 
+}
+
+; This function doesn't use the return value @test5 and tries to lure DAE into
+; marking @test5's return value dead because only this call is unused.
+define i32 @dead() {
+  %DEAD = call i32 @test5()
+  ret i32 0
+}
+
+; This function ensures the retval of @test5 is live.
+define i32 @alive() {
+  %LIVE = call i32 @test5()
+  ret i32 %LIVE
+}