Implement runtime checks for undefined behavior. WIP.

This implements a new flag -fcatch-undefined-behavior.  The flag turns
on additional runtime checks for:

  T a[I];

  a[i]    abort when i < 0 or i >= I.

Future stuff includes shifts by >= bitwidth amounts.

llvm-svn: 91198

1 files changed, 6 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index 1ddfa6d6c02..8820e6ec8b7 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -108,6 +108,7 @@ public:
   uint32_t LLVMPointerWidth;
 
   bool Exceptions;
+  bool CatchUndefined;
 public:
   /// ObjCEHValueStack - Stack of Objective-C exception values, used for
   /// rethrows.
@@ -1266,6 +1267,11 @@ private:
                                     ArgType));
     }
   }
+
+  llvm::BasicBlock *AbortBB;
+  /// getAbortBB - Create a basic block that will call abort.  We'll generate
+  /// a branch around the created basic block as necessary.
+  llvm::BasicBlock* getAbortBB();
 };