Imported Upstream version 6.0.0.172

Former-commit-id: f3cc9b82f3e5bd8f0fd3ebc098f789556b44e9cd

external/llvm/test/Analysis/BasicAA/tailcall-modref.ll

@@ -0,0 +1,16 @@
+; RUN: opt < %s -basicaa -gvn -instcombine -S | FileCheck %s
+
+define i32 @test() {
+; CHECK: ret i32 0
+        %A = alloca i32         ; <i32*> [#uses=3]
+        call void @foo( i32* %A )
+        %X = load i32, i32* %A               ; <i32> [#uses=1]
+        tail call void @bar( )
+        %Y = load i32, i32* %A               ; <i32> [#uses=1]
+        %Z = sub i32 %X, %Y             ; <i32> [#uses=1]
+        ret i32 %Z
+}
+
+declare void @foo(i32*)
+
+declare void @bar()