Insert poisoned paddings between fields in C++ classes so that AddressSanitizer can find intra-object-overflow bugs

Summary:
The general approach is to add extra paddings after every field
in AST/RecordLayoutBuilder.cpp, then add code to CTORs/DTORs that poisons the paddings
(CodeGen/CGClass.cpp).

Everything is done under the flag -fsanitize-address-field-padding. 
The blacklist file (-fsanitize-blacklist) allows to avoid the transformation 
for given classes or source files. 

See also https://code.google.com/p/address-sanitizer/wiki/IntraObjectOverflow

Test Plan: run SPEC2006 and some of the Chromium tests with  -fsanitize-address-field-padding

Reviewers: samsonov, rnk, rsmith

Reviewed By: rsmith

Subscribers: majnemer, cfe-commits

Differential Revision: http://reviews.llvm.org/D5687

llvm-svn: 219961

1 files changed, 1 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index 09b12713a84..49810a8700e 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -1267,6 +1267,7 @@ public:
   void EmitLambdaBlockInvokeBody();
   void EmitLambdaDelegatingInvokeBody(const CXXMethodDecl *MD);
   void EmitLambdaStaticInvokeFunction(const CXXMethodDecl *MD);
+  void EmitAsanPrologueOrEpilogue(bool Prologue);
 
   /// EmitReturnBlock - Emit the unified return block, trying to avoid its
   /// emission when possible.