1 files changed, 42 insertions, 0 deletions
diff --git a/llvm/test/Analysis/BasicAA/licmtest.ll b/llvm/test/Analysis/BasicAA/licmtest.ll
new file mode 100644
index 00000000000..0b1394394e9
--- /dev/null
+++ b/llvm/test/Analysis/BasicAA/licmtest.ll
@@ -0,0 +1,42 @@
+; Test that LICM uses basicaa to do alias analysis, which is capable of 
+; disambiguating some obvious cases.  If LICM is able to disambiguate the
+; two pointers, then the load should be hoisted, and the store sunk.  Thus
+; the loop becomes empty and can be deleted by ADCE. 
+
+; RUN: llvm-upgrade < %s | llvm-as | opt -basicaa -licm --adce | llvm-dis | not grep Loop
+
+%A = global int 7
+%B = global int 8
+%C = global [2 x int ] [ int 4, int 8 ]
+implementation
+
+int %test(bool %c) {
+	%Atmp = load int* %A
+	br label %Loop
+Loop:
+	%ToRemove = load int* %A
+	store int %Atmp, int* %B  ; Store cannot alias %A
+
+	br bool %c, label %Out, label %Loop
+Out:
+	%X = sub int %ToRemove, %Atmp
+	ret int %X
+}
+
+int %test2(bool %c) {
+	br label %Loop
+Loop:
+	%AVal = load int* %A
+	%C0 = getelementptr [2 x int ]* %C, long 0, long 0
+	store int %AVal, int* %C0  ; Store cannot alias %A
+
+	%BVal = load int* %B
+	%C1 = getelementptr [2 x int ]* %C, long 0, long 1
+	store int %BVal, int* %C1  ; Store cannot alias %A, %B, or %C0
+
+	br bool %c, label %Out, label %Loop
+Out:
+	%X = sub int %AVal, %BVal
+	ret int %X
+}
+