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/2008-09-13-VolatileRead.ll b/test/Transforms/AddReadAttrs/2008-09-13-VolatileRead.ll
new file mode 100644
index 0000000..0690083
--- /dev/null
+++ b/test/Transforms/AddReadAttrs/2008-09-13-VolatileRead.ll
@@ -0,0 +1,9 @@
+; RUN: llvm-as < %s | opt -addreadattrs | llvm-dis | not grep read
+; PR2792
+
+@g = global i32 0 ; <i32*> [#uses=1]
+
+define i32 @f() {
+ %t = volatile load i32* @g ; <i32> [#uses=1]
+ ret i32 %t
+}