[ubsan] Use the nicer nullability diagnostic handlers

This is a follow-up to r297700 (Add a nullability sanitizer).

It addresses some FIXME's re: using nullability-specific diagnostic
handlers from compiler-rt, now that the necessary handlers exist.

check-ubsan test updates to follow.

llvm-svn: 297750

3 files changed, 15 insertions, 9 deletions

diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index 5f069bfe46b..34ac95eadc5 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -2938,18 +2938,20 @@ void CodeGenFunction::EmitReturnValueCheck(llvm::Value *RV,
   // Prefer the returns_nonnull attribute if it's present.
   SourceLocation AttrLoc;
   SanitizerMask CheckKind;
+  SanitizerHandler Handler;
   if (RetNNAttr) {
     assert(!requiresReturnValueNullabilityCheck() &&
            "Cannot check nullability and the nonnull attribute");
     AttrLoc = RetNNAttr->getLocation();
     CheckKind = SanitizerKind::ReturnsNonnullAttribute;
+    Handler = SanitizerHandler::NonnullReturn;
   } else {
-    // FIXME: The runtime shouldn't refer to the 'returns_nonnull' attribute.
     if (auto *DD = dyn_cast<DeclaratorDecl>(CurCodeDecl))
       if (auto *TSI = DD->getTypeSourceInfo())
         if (auto FTL = TSI->getTypeLoc().castAs<FunctionTypeLoc>())
           AttrLoc = FTL.getReturnLoc().findNullabilityLoc();
     CheckKind = SanitizerKind::NullabilityReturn;
+    Handler = SanitizerHandler::NullabilityReturn;
   }
 
   SanitizerScope SanScope(this);
@@ -2971,8 +2973,7 @@ void CodeGenFunction::EmitReturnValueCheck(llvm::Value *RV,
   llvm::Constant *StaticData[] = {
       EmitCheckSourceLocation(EndLoc), EmitCheckSourceLocation(AttrLoc),
   };
-  EmitCheck(std::make_pair(Cond, CheckKind), SanitizerHandler::NonnullReturn,
-            StaticData, None);
+  EmitCheck(std::make_pair(Cond, CheckKind), Handler, StaticData, None);
 
   if (requiresReturnValueNullabilityCheck())
     EmitBlock(NoCheck);
@@ -3314,12 +3315,15 @@ void CodeGenFunction::EmitNonNullArgCheck(RValue RV, QualType ArgType,
 
   SourceLocation AttrLoc;
   SanitizerMask CheckKind;
+  SanitizerHandler Handler;
   if (NNAttr) {
     AttrLoc = NNAttr->getLocation();
     CheckKind = SanitizerKind::NonnullAttribute;
+    Handler = SanitizerHandler::NonnullArg;
   } else {
     AttrLoc = PVD->getTypeSourceInfo()->getTypeLoc().findNullabilityLoc();
     CheckKind = SanitizerKind::NullabilityArg;
+    Handler = SanitizerHandler::NullabilityArg;
   }
 
   SanitizerScope SanScope(this);
@@ -3331,8 +3335,7 @@ void CodeGenFunction::EmitNonNullArgCheck(RValue RV, QualType ArgType,
       EmitCheckSourceLocation(ArgLoc), EmitCheckSourceLocation(AttrLoc),
       llvm::ConstantInt::get(Int32Ty, ArgNo + 1),
   };
-  EmitCheck(std::make_pair(Cond, CheckKind), SanitizerHandler::NonnullArg,
-            StaticData, None);
+  EmitCheck(std::make_pair(Cond, CheckKind), Handler, StaticData, None);
 }
 
 void CodeGenFunction::EmitCallArgs(
diff --git a/clang/lib/CodeGen/CGDecl.cpp b/clang/lib/CodeGen/CGDecl.cpp
index cfadce5c221..edfc6741374 100644
--- a/clang/lib/CodeGen/CGDecl.cpp
+++ b/clang/lib/CodeGen/CGDecl.cpp
@@ -685,11 +685,10 @@ void CodeGenFunction::EmitNullabilityCheck(LValue LHS, llvm::Value *RHS,
   // hand side must be nonnull.
   SanitizerScope SanScope(this);
   llvm::Value *IsNotNull = Builder.CreateIsNotNull(RHS);
-  // FIXME: The runtime shouldn't refer to a 'reference'.
   llvm::Constant *StaticData[] = {
       EmitCheckSourceLocation(Loc), EmitCheckTypeDescriptor(LHS.getType()),
-      llvm::ConstantInt::get(Int8Ty, 1),
-      llvm::ConstantInt::get(Int8Ty, TCK_ReferenceBinding)};
+      llvm::ConstantInt::get(Int8Ty, 0), //< The LogAlignment info is unused.
+      llvm::ConstantInt::get(Int8Ty, TCK_NonnullAssign)};
   EmitCheck({{IsNotNull, SanitizerKind::NullabilityAssign}},
             SanitizerHandler::TypeMismatch, StaticData, RHS);
 }
diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index 2db8a18ceff..7e99bdb73c4 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -115,6 +115,8 @@ enum TypeEvaluationKind {
   SANITIZER_CHECK(MissingReturn, missing_return, 0)                            \
   SANITIZER_CHECK(MulOverflow, mul_overflow, 0)                                \
   SANITIZER_CHECK(NegateOverflow, negate_overflow, 0)                          \
+  SANITIZER_CHECK(NullabilityArg, nullability_arg, 0)                          \
+  SANITIZER_CHECK(NullabilityReturn, nullability_return, 0)                    \
   SANITIZER_CHECK(NonnullArg, nonnull_arg, 0)                                  \
   SANITIZER_CHECK(NonnullReturn, nonnull_return, 0)                            \
   SANITIZER_CHECK(OutOfBounds, out_of_bounds, 0)                               \
@@ -2290,7 +2292,9 @@ public:
     TCK_Upcast,
     /// Checking the operand of a cast to a virtual base object. Must be an
     /// object within its lifetime.
-    TCK_UpcastToVirtualBase
+    TCK_UpcastToVirtualBase,
+    /// Checking the value assigned to a _Nonnull pointer. Must not be null.
+    TCK_NonnullAssign
   };
 
   /// \brief Whether any type-checking sanitizers are enabled. If \c false,