[FuncAttrs] Remove "access range attributes" for read-none functions

The presence of readnone and an access range attribute (argmemonly,
inaccessiblememonly, inaccessiblemem_or_argmemonly) is considered an
error by the verifier. This seems strict but also not wrong. This
patch makes sure function attribute detection will remove all access
range attributes for readnone functions.

llvm-svn: 341927

1 files changed, 32 insertions, 0 deletions

diff --git a/llvm/test/Transforms/FunctionAttrs/incompatible_fn_attrs.ll b/llvm/test/Transforms/FunctionAttrs/incompatible_fn_attrs.ll
new file mode 100644
index 00000000000..79af817ff03
--- /dev/null
+++ b/llvm/test/Transforms/FunctionAttrs/incompatible_fn_attrs.ll
@@ -0,0 +1,32 @@
+; RUN: opt -S -o - -functionattrs %s | FileCheck %s
+; RUN: opt -S -o - -passes=function-attrs %s | FileCheck %s
+
+; Verify we remove argmemonly/inaccessiblememonly/inaccessiblemem_or_argmemonly
+; function attributes when we derive readnone.
+
+; Function Attrs: argmemonly
+define i32* @given_argmem_infer_readnone(i32* %p) #0 {
+; CHECK: define i32* @given_argmem_infer_readnone(i32* readnone returned %p) #0 {
+entry:
+  ret i32* %p
+}
+
+; Function Attrs: inaccessiblememonly
+define i32* @given_inaccessible_infer_readnone(i32* %p) #1 {
+; CHECK: define i32* @given_inaccessible_infer_readnone(i32* readnone returned %p) #0 {
+entry:
+  ret i32* %p
+}
+
+; Function Attrs: inaccessiblemem_or_argmemonly
+define i32* @given_inaccessible_or_argmem_infer_readnone(i32* %p) #2 {
+; CHECK: define i32* @given_inaccessible_or_argmem_infer_readnone(i32* readnone returned %p) #0 {
+entry:
+  ret i32* %p
+}
+
+attributes #0 = { argmemonly }
+attributes #1 = { inaccessiblememonly }
+attributes #2 = { inaccessiblemem_or_argmemonly }
+; CHECK: attributes #0 = { norecurse nounwind readnone }
+; CHECK-NOT: attributes