Implement function type checker for the undefined behavior sanitizer.

This uses function prefix data to store function type information at the
function pointer.

Differential Revision: http://llvm-reviews.chandlerc.com/D1338

llvm-svn: 193058

1 files changed, 8 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/TargetInfo.h b/clang/lib/CodeGen/TargetInfo.h
index a7fb88649a3..f631f3102d0 100644
--- a/clang/lib/CodeGen/TargetInfo.h
+++ b/clang/lib/CodeGen/TargetInfo.h
@@ -21,6 +21,7 @@
 #include "llvm/ADT/SmallString.h"
 
 namespace llvm {
+  class Constant;
   class GlobalValue;
   class Type;
   class Value;
@@ -136,6 +137,13 @@ namespace clang {
       return "";
     }
 
+    /// Return a constant used by UBSan as a signature to identify functions
+    /// possessing type information, or 0 if the platform is unsupported.
+    virtual llvm::Constant *getUBSanFunctionSignature(
+        CodeGen::CodeGenModule &CGM) const {
+      return 0;
+    }
+
     /// Determine whether a call to an unprototyped functions under
     /// the given calling convention should use the variadic
     /// convention or the non-variadic convention.