Vendor import of clang trunk r304460:vendor/clang/clang-trunk-r304460

https://llvm.org/svn/llvm-project/cfe/trunk@304460

1 files changed, 48 insertions, 12 deletions

diff --git a/lib/CodeGen/CGExpr.cpp b/lib/CodeGen/CGExpr.cpp
index b918a663ce5c..84ce896506d5 100644
--- a/lib/CodeGen/CGExpr.cpp
+++ b/lib/CodeGen/CGExpr.cpp
@@ -3002,9 +3002,10 @@ static llvm::Value *emitArraySubscriptGEP(CodeGenFunction &CGF,
                                           llvm::Value *ptr,
                                           ArrayRef<llvm::Value*> indices,
                                           bool inbounds,
+                                          SourceLocation loc,
                                     const llvm::Twine &name = "arrayidx") {
   if (inbounds) {
-    return CGF.Builder.CreateInBoundsGEP(ptr, indices, name);
+    return CGF.EmitCheckedInBoundsGEP(ptr, indices, loc, name);
   } else {
     return CGF.Builder.CreateGEP(ptr, indices, name);
   }
@@ -3035,8 +3036,9 @@ static QualType getFixedSizeElementType(const ASTContext &ctx,
 }
 
 static Address emitArraySubscriptGEP(CodeGenFunction &CGF, Address addr,
-                                     ArrayRef<llvm::Value*> indices,
+                                     ArrayRef<llvm::Value *> indices,
                                      QualType eltType, bool inbounds,
+                                     SourceLocation loc,
                                      const llvm::Twine &name = "arrayidx") {
   // All the indices except that last must be zero.
 #ifndef NDEBUG
@@ -3057,7 +3059,7 @@ static Address emitArraySubscriptGEP(CodeGenFunction &CGF, Address addr,
     getArrayElementAlign(addr.getAlignment(), indices.back(), eltSize);
 
   llvm::Value *eltPtr =
-    emitArraySubscriptGEP(CGF, addr.getPointer(), indices, inbounds, name);
+    emitArraySubscriptGEP(CGF, addr.getPointer(), indices, inbounds, loc, name);
   return Address(eltPtr, eltAlign);
 }
 
@@ -3110,7 +3112,8 @@ LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
     Address Addr = EmitExtVectorElementLValue(LV);
 
     QualType EltType = LV.getType()->castAs<VectorType>()->getElementType();
-    Addr = emitArraySubscriptGEP(*this, Addr, Idx, EltType, /*inbounds*/ true);
+    Addr = emitArraySubscriptGEP(*this, Addr, Idx, EltType, /*inbounds*/ true,
+                                 E->getExprLoc());
     return MakeAddrLValue(Addr, EltType, LV.getBaseInfo());
   }
 
@@ -3138,7 +3141,8 @@ LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
     }
 
     Addr = emitArraySubscriptGEP(*this, Addr, Idx, vla->getElementType(),
-                                 !getLangOpts().isSignedOverflowDefined());
+                                 !getLangOpts().isSignedOverflowDefined(),
+                                 E->getExprLoc());
 
   } else if (const ObjCObjectType *OIT = E->getType()->getAs<ObjCObjectType>()){
     // Indexing over an interface, as in "NSString *P; P[4];"
@@ -3163,8 +3167,8 @@ LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
     // Do the GEP.
     CharUnits EltAlign =
       getArrayElementAlign(Addr.getAlignment(), Idx, InterfaceSize);
-    llvm::Value *EltPtr =
-      emitArraySubscriptGEP(*this, Addr.getPointer(), ScaledIdx, false);
+    llvm::Value *EltPtr = emitArraySubscriptGEP(
+        *this, Addr.getPointer(), ScaledIdx, false, E->getExprLoc());
     Addr = Address(EltPtr, EltAlign);
 
     // Cast back.
@@ -3189,14 +3193,16 @@ LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
     Addr = emitArraySubscriptGEP(*this, ArrayLV.getAddress(),
                                  {CGM.getSize(CharUnits::Zero()), Idx},
                                  E->getType(),
-                                 !getLangOpts().isSignedOverflowDefined());
+                                 !getLangOpts().isSignedOverflowDefined(),
+                                 E->getExprLoc());
     BaseInfo = ArrayLV.getBaseInfo();
   } else {
     // The base must be a pointer; emit it with an estimate of its alignment.
     Addr = EmitPointerWithAlignment(E->getBase(), &BaseInfo);
     auto *Idx = EmitIdxAfterBase(/*Promote*/true);
     Addr = emitArraySubscriptGEP(*this, Addr, Idx, E->getType(),
-                                 !getLangOpts().isSignedOverflowDefined());
+                                 !getLangOpts().isSignedOverflowDefined(),
+                                 E->getExprLoc());
   }
 
   LValue LV = MakeAddrLValue(Addr, E->getType(), BaseInfo);
@@ -3368,7 +3374,8 @@ LValue CodeGenFunction::EmitOMPArraySectionExpr(const OMPArraySectionExpr *E,
     else
       Idx = Builder.CreateNSWMul(Idx, NumElements);
     EltPtr = emitArraySubscriptGEP(*this, Base, Idx, VLA->getElementType(),
-                                   !getLangOpts().isSignedOverflowDefined());
+                                   !getLangOpts().isSignedOverflowDefined(),
+                                   E->getExprLoc());
   } else if (const Expr *Array = isSimpleArrayDecayOperand(E->getBase())) {
     // If this is A[i] where A is an array, the frontend will have decayed the
     // base to be a ArrayToPointerDecay implicit cast.  While correct, it is
@@ -3387,13 +3394,15 @@ LValue CodeGenFunction::EmitOMPArraySectionExpr(const OMPArraySectionExpr *E,
     // Propagate the alignment from the array itself to the result.
     EltPtr = emitArraySubscriptGEP(
         *this, ArrayLV.getAddress(), {CGM.getSize(CharUnits::Zero()), Idx},
-        ResultExprTy, !getLangOpts().isSignedOverflowDefined());
+        ResultExprTy, !getLangOpts().isSignedOverflowDefined(),
+        E->getExprLoc());
     BaseInfo = ArrayLV.getBaseInfo();
   } else {
     Address Base = emitOMPArraySectionBase(*this, E->getBase(), BaseInfo,
                                            BaseTy, ResultExprTy, IsLowerBound);
     EltPtr = emitArraySubscriptGEP(*this, Base, Idx, ResultExprTy,
-                                   !getLangOpts().isSignedOverflowDefined());
+                                   !getLangOpts().isSignedOverflowDefined(),
+                                   E->getExprLoc());
   }
 
   return MakeAddrLValue(EltPtr, ResultExprTy, BaseInfo);
@@ -3530,6 +3539,25 @@ static Address emitAddrOfFieldStorage(CodeGenFunction &CGF, Address base,
   return CGF.Builder.CreateStructGEP(base, idx, offset, field->getName());
 }
 
+static bool hasAnyVptr(const QualType Type, const ASTContext &Context) {
+  const auto *RD = Type.getTypePtr()->getAsCXXRecordDecl();
+  if (!RD)
+    return false;
+
+  if (RD->isDynamicClass())
+    return true;
+
+  for (const auto &Base : RD->bases())
+    if (hasAnyVptr(Base.getType(), Context))
+      return true;
+
+  for (const FieldDecl *Field : RD->fields())
+    if (hasAnyVptr(Field->getType(), Context))
+      return true;
+
+  return false;
+}
+
 LValue CodeGenFunction::EmitLValueForField(LValue base,
                                            const FieldDecl *field) {
   LValueBaseInfo BaseInfo = base.getBaseInfo();
@@ -3572,6 +3600,14 @@ LValue CodeGenFunction::EmitLValueForField(LValue base,
     assert(!type->isReferenceType() && "union has reference member");
     // TODO: handle path-aware TBAA for union.
     TBAAPath = false;
+
+    const auto FieldType = field->getType();
+    if (CGM.getCodeGenOpts().StrictVTablePointers &&
+        hasAnyVptr(FieldType, getContext()))
+      // Because unions can easily skip invariant.barriers, we need to add
+      // a barrier every time CXXRecord field with vptr is referenced.
+      addr = Address(Builder.CreateInvariantGroupBarrier(addr.getPointer()),
+                     addr.getAlignment());
   } else {
     // For structs, we GEP to the field that the record layout suggests.
     addr = emitAddrOfFieldStorage(*this, addr, field);