Implement nonnull-attribute sanitizer

Summary:
This patch implements a new UBSan check, which verifies
that function arguments declared to be nonnull with __attribute__((nonnull))
are actually nonnull in runtime.

To implement this check, we pass FunctionDecl to CodeGenFunction::EmitCallArgs
(where applicable) and if function declaration has nonnull attribute specified
for a certain formal parameter, we compare the corresponding RValue to null as
soon as it's calculated.

Test Plan: regression test suite

Reviewers: rsmith

Reviewed By: rsmith

Subscribers: cfe-commits, rnk

Differential Revision: http://reviews.llvm.org/D5082

llvm-svn: 217389

1 files changed, 5 insertions, 2 deletions

diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index 4841b53..ff74ce9 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -2625,6 +2625,7 @@ public:
   void EmitCallArgs(CallArgList &Args, const T *CallArgTypeInfo,
                     CallExpr::const_arg_iterator ArgBeg,
                     CallExpr::const_arg_iterator ArgEnd,
+                    const FunctionDecl *CalleeDecl = nullptr,
                     unsigned ParamsToSkip = 0, bool ForceColumnInfo = false) {
     SmallVector<QualType, 16> ArgTypes;
     CallExpr::const_arg_iterator Arg = ArgBeg;
@@ -2673,13 +2674,15 @@ public:
     for (; Arg != ArgEnd; ++Arg)
       ArgTypes.push_back(Arg->getType());
 
-    EmitCallArgs(Args, ArgTypes, ArgBeg, ArgEnd, ForceColumnInfo);
+    EmitCallArgs(Args, ArgTypes, ArgBeg, ArgEnd, CalleeDecl, ParamsToSkip,
+                 ForceColumnInfo);
   }
 
   void EmitCallArgs(CallArgList &Args, ArrayRef<QualType> ArgTypes,
                     CallExpr::const_arg_iterator ArgBeg,
                     CallExpr::const_arg_iterator ArgEnd,
-                    bool ForceColumnInfo = false);
+                    const FunctionDecl *CalleeDecl = nullptr,
+                    unsigned ParamsToSkip = 0, bool ForceColumnInfo = false);
 
 private:
   const TargetCodeGenInfo &getTargetHooks() const {