Add a new pass AddReadAttrs which works out which functions
can get the readnone/readonly attributes, and gives them it.
The plan is to remove markmodref (which did the same thing
by querying GlobalsModRef) and delete the analogous
functionality from GlobalsModRef.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56341 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Transforms/AddReadAttrs/2008-09-03-Mutual.ll b/test/Transforms/AddReadAttrs/2008-09-03-Mutual.ll
new file mode 100644
index 0000000..0a4f085
--- /dev/null
+++ b/test/Transforms/AddReadAttrs/2008-09-03-Mutual.ll
@@ -0,0 +1,11 @@
+; RUN: llvm-as < %s | opt -addreadattrs | llvm-dis | grep readnone
+
+define i32 @a() {
+	%tmp = call i32 @b( )		; <i32> [#uses=1]
+	ret i32 %tmp
+}
+
+define i32 @b() {
+	%tmp = call i32 @a( )		; <i32> [#uses=1]
+	ret i32 %tmp
+}