[UBSan] Add !nosanitize metadata to the code generated by UBSan.

This is used to mark the instructions emitted by Clang to implement
variety of UBSan checks. Generally, we don't want to instrument these
instructions with another sanitizers (like ASan).

Reviewed in http://reviews.llvm.org/D4544

llvm-svn: 213291

1 files changed, 6 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp
index a43cf30da73..63731b7b7d0 100644
--- a/clang/lib/CodeGen/CGExpr.cpp
+++ b/clang/lib/CodeGen/CGExpr.cpp
@@ -458,6 +458,8 @@ void CodeGenFunction::EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc,
   if (Address->getType()->getPointerAddressSpace())
     return;
 
+  SanitizerScope SanScope(this);
+
   llvm::Value *Cond = nullptr;
   llvm::BasicBlock *Done = nullptr;
 
@@ -654,6 +656,7 @@ void CodeGenFunction::EmitBoundsCheck(const Expr *E, const Expr *Base,
                                       bool Accessed) {
   assert(SanOpts->ArrayBounds &&
          "should not be called unless adding bounds checks");
+  SanitizerScope SanScope(this);
 
   QualType IndexedType;
   llvm::Value *Bound = getArrayIndexingBound(*this, Base, IndexedType);
@@ -1129,6 +1132,7 @@ llvm::Value *CodeGenFunction::EmitLoadOfScalar(llvm::Value *Addr, bool Volatile,
 
   if ((SanOpts->Bool && hasBooleanRepresentation(Ty)) ||
       (SanOpts->Enum && Ty->getAs<EnumType>())) {
+    SanitizerScope SanScope(this);
     llvm::APInt Min, End;
     if (getRangeForType(*this, Ty, Min, End, true)) {
       --End;
@@ -2183,6 +2187,7 @@ void CodeGenFunction::EmitCheck(llvm::Value *Checked, StringRef CheckName,
                                 ArrayRef<llvm::Value *> DynamicArgs,
                                 CheckRecoverableKind RecoverKind) {
   assert(SanOpts != &SanitizerOptions::Disabled);
+  assert(IsSanitizerScope);
 
   if (CGM.getCodeGenOpts().SanitizeUndefinedTrapOnError) {
     assert (RecoverKind != CRK_AlwaysRecoverable &&
@@ -3231,6 +3236,7 @@ RValue CodeGenFunction::EmitCall(QualType CalleeType, llvm::Value *Callee,
       (!TargetDecl || !isa<FunctionDecl>(TargetDecl))) {
     if (llvm::Constant *PrefixSig =
             CGM.getTargetCodeGenInfo().getUBSanFunctionSignature(CGM)) {
+      SanitizerScope SanScope(this);
       llvm::Constant *FTRTTIConst =
           CGM.GetAddrOfRTTIDescriptor(QualType(FnType, 0), /*ForEH=*/true);
       llvm::Type *PrefixStructTyElems[] = {