Add the ShadowCallStack attribute

Summary:
Introduce the ShadowCallStack function attribute. It's added to
functions compiled with -fsanitize=shadow-call-stack in order to mark
functions to be instrumented by a ShadowCallStack pass to be submitted
in a separate change.

Reviewers: pcc, kcc, kubamracek

Reviewed By: pcc, kcc

Subscribers: cryptoad, mehdi_amini, javed.absar, llvm-commits, kcc

Differential Revision: https://reviews.llvm.org/D44800

llvm-svn: 329108

1 files changed, 9 insertions, 2 deletions

diff --git a/llvm/test/Bitcode/attributes.ll b/llvm/test/Bitcode/attributes.ll
index 8c74b3fb36b..de3cf8dd4d7 100644
--- a/llvm/test/Bitcode/attributes.ll
+++ b/llvm/test/Bitcode/attributes.ll
@@ -204,7 +204,7 @@ define void @f34()
 ; CHECK: define void @f34()
 {
         call void @nobuiltin() nobuiltin
-; CHECK: call void @nobuiltin() #35
+; CHECK: call void @nobuiltin() #36
         ret void;
 }
 
@@ -345,6 +345,12 @@ define void @f58() sanitize_hwaddress
         ret void;
 }
 
+; CHECK: define void @f59() #35
+define void @f59() shadowcallstack
+{
+  ret void
+}
+
 ; CHECK: attributes #0 = { noreturn }
 ; CHECK: attributes #1 = { nounwind }
 ; CHECK: attributes #2 = { readnone }
@@ -380,4 +386,5 @@ define void @f58() sanitize_hwaddress
 ; CHECK: attributes #32 = { writeonly }
 ; CHECK: attributes #33 = { speculatable }
 ; CHECK: attributes #34 = { sanitize_hwaddress }
-; CHECK: attributes #35 = { nobuiltin }
+; CHECK: attributes #35 = { shadowcallstack }
+; CHECK: attributes #36 = { nobuiltin }