add wraps bypass for implicit-(un)signed-integer-truncation sanitizers

Signed-off-by: Justin Stitt <[email protected]>

Author: JustinStitt

clang/lib/CodeGen/CGExprScalar.cpp

@@ -1108,7 +1108,8 @@ void ScalarExprEmitter::EmitIntegerTruncationCheck(Value *Src, QualType SrcType,
   // If the comparison result is 'i1 false', then the truncation was lossy.
 
   // Do we care about this type of truncation?
-  if (!CGF.SanOpts.has(Check.second.second))
+  if (!CGF.SanOpts.has(Check.second.second) ||
+      DstType.getTypePtr()->hasAttr(attr::Wraps))
     return;
 
   llvm::Constant *StaticArgs[] = {

clang/lib/Sema/SemaChecking.cpp

@@ -16439,7 +16439,8 @@ static void CheckImplicitConversion(Sema &S, Expr *E, QualType T,
       S.Context, E, S.isConstantEvaluatedContext(), /*Approximate=*/true);
   IntRange TargetRange = IntRange::forTargetOfCanonicalType(S.Context, Target);
 
-  if (LikelySourceRange.Width > TargetRange.Width) {
+  if (LikelySourceRange.Width > TargetRange.Width &&
+      !T.getTypePtr()->hasAttr(attr::Wraps)) {
     // If the source is a constant, use a default-on diagnostic.
     // TODO: this should happen for bitfield stores, too.
     Expr::EvalResult Result;
@@ -16487,7 +16488,7 @@ static void CheckImplicitConversion(Sema &S, Expr *E, QualType T,
 
   if (TargetRange.Width == LikelySourceRange.Width &&
       !TargetRange.NonNegative && LikelySourceRange.NonNegative &&
-      Source->isSignedIntegerType()) {
+      Source->isSignedIntegerType() && !T.getTypePtr()->hasAttr(attr::Wraps)) {
     // Warn when doing a signed to signed conversion, warn if the positive
     // source value is exactly the width of the target type, which will
     // cause a negative value to be stored.