new testcase that DS-AA is causing to be miscompiled.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@20813 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/Analysis/DSGraph/2005-03-24-Global-Arg-Alias.ll b/test/Analysis/DSGraph/2005-03-24-Global-Arg-Alias.ll
new file mode 100644 (file)
index 0000000..2293388
--- /dev/null
+++ b/test/Analysis/DSGraph/2005-03-24-Global-Arg-Alias.ll
@@ -0,0 +1,26 @@
+; RUN: llvm-as < %s | opt -ds-aa -load-vn -gcse | llvm-dis | grep 'load int* %L'
+
+%G = internal global int* null
+
+int %caller(bool %P) {
+  %L = alloca int
+  call void %callee(bool %P, int* %L)
+
+  ;; At this point, G could point to L, so we can't eliminate these operations.
+  %GP = load int** %G
+  store int 17, int* %L
+  store int 18, int* %GP  ;; might clober L
+
+  %A = load int* %L    ;; is not necessarily 17!
+  ret int %A
+}
+
+internal void %callee(bool %Cond, int* %P) {
+  br bool %Cond, label %T, label %F
+T:
+  store int* %P, int** %G
+  ret void
+F:
+  ret void
+}
+