Add a testcase which demonstrates alias analysis pass precedence.

llvm-svn: 118755

1 files changed, 21 insertions, 0 deletions

diff --git a/llvm/test/Analysis/TypeBasedAliasAnalysis/precedence.ll b/llvm/test/Analysis/TypeBasedAliasAnalysis/precedence.ll
new file mode 100644
index 00000000000..b2095b05722
--- /dev/null
+++ b/llvm/test/Analysis/TypeBasedAliasAnalysis/precedence.ll
@@ -0,0 +1,21 @@
+; RUN: opt -enable-tbaa -basicaa -tbaa -gvn -instcombine -S < %s | grep {ret i32 0}
+; RUN: opt -enable-tbaa -tbaa -basicaa -gvn -instcombine -S < %s | grep {ret i32 1075000115}
+
+; According to the TBAA metadata the load and store don't alias. However,
+; according to the actual code, they do. The order of the alias analysis
+; passes should determine which of these takes precedence.
+
+target datalayout = "e-p:64:64:64"
+
+define i32 @trouble(i32* %x) nounwind ssp {
+entry:
+  store i32 0, i32* %x, !tbaa !0
+  %0 = bitcast i32* %x to float*
+  store float 0x4002666660000000, float* %0, !tbaa !3
+  %tmp3 = load i32* %x, !tbaa !0
+  ret i32 %tmp3
+}
+
+!0 = metadata !{metadata !"int", metadata !1}
+!1 = metadata !{metadata !"simple"}
+!3 = metadata !{metadata !"float", metadata !1}