[CodeGen][arm64e] Add methods and data members to Address, which are needed to authenticate signed pointers (#86923)

To authenticate pointers, CodeGen needs access to the key and
discriminators that were used to sign the pointer. That information is
sometimes known from the context, but not always, which is why `Address`
needs to hold that information.

This patch adds methods and data members to `Address`, which will be
needed in subsequent patches to authenticate signed pointers, and uses
the newly added methods throughout CodeGen. Although this patch isn't
strictly NFC as it causes CodeGen to use different code paths in some
cases (e.g., `mergeAddressesInConditionalExpr`), it doesn't cause any
changes in functionality as it doesn't add any information needed for
authentication.

In addition to the changes mentioned above, this patch introduces class
`RawAddress`, which contains a pointer that we know is unsigned, and
adds several new functions for creating `Address` and `LValue` objects.

This reapplies d9a685a9dd589486e882b722e513ee7b8c84870c, which was
reverted because it broke ubsan bots. There seems to be a bug in
coroutine code-gen, which is causing EmitTypeCheck to use the wrong
alignment. For now, pass alignment zero to EmitTypeCheck so that it can
compute the correct alignment based on the passed type (see function
EmitCXXMemberOrOperatorMemberCallExpr).

1 files changed, 55 insertions, 60 deletions

diff --git a/clang/lib/CodeGen/CGExprCXX.cpp b/clang/lib/CodeGen/CGExprCXX.cpp
index 35da0f1a89bc..a4fb673284ce 100644
--- a/clang/lib/CodeGen/CGExprCXX.cpp
+++ b/clang/lib/CodeGen/CGExprCXX.cpp
@@ -280,7 +280,8 @@ RValue CodeGenFunction::EmitCXXMemberOrOperatorMemberCallExpr(
     LValueBaseInfo BaseInfo;
     TBAAAccessInfo TBAAInfo;
     Address ThisValue = EmitPointerWithAlignment(Base, &BaseInfo, &TBAAInfo);
-    This = MakeAddrLValue(ThisValue, Base->getType(), BaseInfo, TBAAInfo);
+    This = MakeAddrLValue(ThisValue, Base->getType()->getPointeeType(),
+                          BaseInfo, TBAAInfo);
   } else {
     This = EmitLValue(Base);
   }
@@ -353,10 +354,12 @@ RValue CodeGenFunction::EmitCXXMemberOrOperatorMemberCallExpr(
     if (IsImplicitObjectCXXThis || isa<DeclRefExpr>(IOA))
       SkippedChecks.set(SanitizerKind::Null, true);
   }
-  EmitTypeCheck(CodeGenFunction::TCK_MemberCall, CallLoc,
-                This.getPointer(*this),
-                C.getRecordType(CalleeDecl->getParent()),
-                /*Alignment=*/CharUnits::Zero(), SkippedChecks);
+
+  if (sanitizePerformTypeCheck())
+    EmitTypeCheck(CodeGenFunction::TCK_MemberCall, CallLoc,
+                  This.emitRawPointer(*this),
+                  C.getRecordType(CalleeDecl->getParent()),
+                  /*Alignment=*/CharUnits::Zero(), SkippedChecks);
 
   // C++ [class.virtual]p12:
   //   Explicit qualification with the scope operator (5.1) suppresses the
@@ -455,7 +458,7 @@ CodeGenFunction::EmitCXXMemberPointerCallExpr(const CXXMemberCallExpr *E,
   else
     This = EmitLValue(BaseExpr, KnownNonNull).getAddress(*this);
 
-  EmitTypeCheck(TCK_MemberCall, E->getExprLoc(), This.getPointer(),
+  EmitTypeCheck(TCK_MemberCall, E->getExprLoc(), This.emitRawPointer(*this),
                 QualType(MPT->getClass(), 0));
 
   // Get the member function pointer.
@@ -1109,9 +1112,10 @@ void CodeGenFunction::EmitNewArrayInitializer(
       // alloca.
       EndOfInit = CreateTempAlloca(BeginPtr.getType(), getPointerAlign(),
                                    "array.init.end");
-      CleanupDominator = Builder.CreateStore(BeginPtr.getPointer(), EndOfInit);
-      pushIrregularPartialArrayCleanup(BeginPtr.getPointer(), EndOfInit,
-                                       ElementType, ElementAlign,
+      CleanupDominator =
+          Builder.CreateStore(BeginPtr.emitRawPointer(*this), EndOfInit);
+      pushIrregularPartialArrayCleanup(BeginPtr.emitRawPointer(*this),
+                                       EndOfInit, ElementType, ElementAlign,
                                        getDestroyer(DtorKind));
       Cleanup = EHStack.stable_begin();
     }
@@ -1123,16 +1127,17 @@ void CodeGenFunction::EmitNewArrayInitializer(
       // element.  TODO: some of these stores can be trivially
       // observed to be unnecessary.
       if (EndOfInit.isValid()) {
-        Builder.CreateStore(CurPtr.getPointer(), EndOfInit);
+        Builder.CreateStore(CurPtr.emitRawPointer(*this), EndOfInit);
       }
       // FIXME: If the last initializer is an incomplete initializer list for
       // an array, and we have an array filler, we can fold together the two
       // initialization loops.
       StoreAnyExprIntoOneUnit(*this, IE, IE->getType(), CurPtr,
                               AggValueSlot::DoesNotOverlap);
-      CurPtr = Address(Builder.CreateInBoundsGEP(
-                           CurPtr.getElementType(), CurPtr.getPointer(),
-                           Builder.getSize(1), "array.exp.next"),
+      CurPtr = Address(Builder.CreateInBoundsGEP(CurPtr.getElementType(),
+                                                 CurPtr.emitRawPointer(*this),
+                                                 Builder.getSize(1),
+                                                 "array.exp.next"),
                        CurPtr.getElementType(),
                        StartAlign.alignmentAtOffset((++i) * ElementSize));
     }
@@ -1186,7 +1191,7 @@ void CodeGenFunction::EmitNewArrayInitializer(
     // FIXME: Share this cleanup with the constructor call emission rather than
     // having it create a cleanup of its own.
     if (EndOfInit.isValid())
-      Builder.CreateStore(CurPtr.getPointer(), EndOfInit);
+      Builder.CreateStore(CurPtr.emitRawPointer(*this), EndOfInit);
 
     // Emit a constructor call loop to initialize the remaining elements.
     if (InitListElements)
@@ -1249,15 +1254,15 @@ void CodeGenFunction::EmitNewArrayInitializer(
   llvm::BasicBlock *ContBB = createBasicBlock("new.loop.end");
 
   // Find the end of the array, hoisted out of the loop.
-  llvm::Value *EndPtr =
-    Builder.CreateInBoundsGEP(BeginPtr.getElementType(), BeginPtr.getPointer(),
-                              NumElements, "array.end");
+  llvm::Value *EndPtr = Builder.CreateInBoundsGEP(
+      BeginPtr.getElementType(), BeginPtr.emitRawPointer(*this), NumElements,
+      "array.end");
 
   // If the number of elements isn't constant, we have to now check if there is
   // anything left to initialize.
   if (!ConstNum) {
-    llvm::Value *IsEmpty =
-      Builder.CreateICmpEQ(CurPtr.getPointer(), EndPtr, "array.isempty");
+    llvm::Value *IsEmpty = Builder.CreateICmpEQ(CurPtr.emitRawPointer(*this),
+                                                EndPtr, "array.isempty");
     Builder.CreateCondBr(IsEmpty, ContBB, LoopBB);
   }
 
@@ -1267,19 +1272,20 @@ void CodeGenFunction::EmitNewArrayInitializer(
   // Set up the current-element phi.
   llvm::PHINode *CurPtrPhi =
       Builder.CreatePHI(CurPtr.getType(), 2, "array.cur");
-  CurPtrPhi->addIncoming(CurPtr.getPointer(), EntryBB);
+  CurPtrPhi->addIncoming(CurPtr.emitRawPointer(*this), EntryBB);
 
   CurPtr = Address(CurPtrPhi, CurPtr.getElementType(), ElementAlign);
 
   // Store the new Cleanup position for irregular Cleanups.
   if (EndOfInit.isValid())
-    Builder.CreateStore(CurPtr.getPointer(), EndOfInit);
+    Builder.CreateStore(CurPtr.emitRawPointer(*this), EndOfInit);
 
   // Enter a partial-destruction Cleanup if necessary.
   if (!CleanupDominator && needsEHCleanup(DtorKind)) {
-    pushRegularPartialArrayCleanup(BeginPtr.getPointer(), CurPtr.getPointer(),
-                                   ElementType, ElementAlign,
-                                   getDestroyer(DtorKind));
+    llvm::Value *BeginPtrRaw = BeginPtr.emitRawPointer(*this);
+    llvm::Value *CurPtrRaw = CurPtr.emitRawPointer(*this);
+    pushRegularPartialArrayCleanup(BeginPtrRaw, CurPtrRaw, ElementType,
+                                   ElementAlign, getDestroyer(DtorKind));
     Cleanup = EHStack.stable_begin();
     CleanupDominator = Builder.CreateUnreachable();
   }
@@ -1295,9 +1301,8 @@ void CodeGenFunction::EmitNewArrayInitializer(
   }
 
   // Advance to the next element by adjusting the pointer type as necessary.
-  llvm::Value *NextPtr =
-    Builder.CreateConstInBoundsGEP1_32(ElementTy, CurPtr.getPointer(), 1,
-                                       "array.next");
+  llvm::Value *NextPtr = Builder.CreateConstInBoundsGEP1_32(
+      ElementTy, CurPtr.emitRawPointer(*this), 1, "array.next");
 
   // Check whether we've gotten to the end of the array and, if so,
   // exit the loop.
@@ -1523,14 +1528,9 @@ static void EnterNewDeleteCleanup(CodeGenFunction &CGF,
 
     typedef CallDeleteDuringNew<DirectCleanupTraits> DirectCleanup;
 
-    DirectCleanup *Cleanup = CGF.EHStack
-      .pushCleanupWithExtra<DirectCleanup>(EHCleanup,
-                                           E->getNumPlacementArgs(),
-                                           E->getOperatorDelete(),
-                                           NewPtr.getPointer(),
-                                           AllocSize,
-                                           E->passAlignment(),
-                                           AllocAlign);
+    DirectCleanup *Cleanup = CGF.EHStack.pushCleanupWithExtra<DirectCleanup>(
+        EHCleanup, E->getNumPlacementArgs(), E->getOperatorDelete(),
+        NewPtr.emitRawPointer(CGF), AllocSize, E->passAlignment(), AllocAlign);
     for (unsigned I = 0, N = E->getNumPlacementArgs(); I != N; ++I) {
       auto &Arg = NewArgs[I + NumNonPlacementArgs];
       Cleanup->setPlacementArg(I, Arg.getRValue(CGF), Arg.Ty);
@@ -1541,7 +1541,7 @@ static void EnterNewDeleteCleanup(CodeGenFunction &CGF,
 
   // Otherwise, we need to save all this stuff.
   DominatingValue<RValue>::saved_type SavedNewPtr =
-    DominatingValue<RValue>::save(CGF, RValue::get(NewPtr.getPointer()));
+      DominatingValue<RValue>::save(CGF, RValue::get(NewPtr, CGF));
   DominatingValue<RValue>::saved_type SavedAllocSize =
     DominatingValue<RValue>::save(CGF, RValue::get(AllocSize));
 
@@ -1618,14 +1618,14 @@ llvm::Value *CodeGenFunction::EmitCXXNewExpr(const CXXNewExpr *E) {
     // In these cases, discard the computed alignment and use the
     // formal alignment of the allocated type.
     if (BaseInfo.getAlignmentSource() != AlignmentSource::Decl)
-      allocation = allocation.withAlignment(allocAlign);
+      allocation.setAlignment(allocAlign);
 
     // Set up allocatorArgs for the call to operator delete if it's not
     // the reserved global operator.
     if (E->getOperatorDelete() &&
         !E->getOperatorDelete()->isReservedGlobalPlacementOperator()) {
       allocatorArgs.add(RValue::get(allocSize), getContext().getSizeType());
-      allocatorArgs.add(RValue::get(allocation.getPointer()), arg->getType());
+      allocatorArgs.add(RValue::get(allocation, *this), arg->getType());
     }
 
   } else {
@@ -1713,8 +1713,7 @@ llvm::Value *CodeGenFunction::EmitCXXNewExpr(const CXXNewExpr *E) {
     llvm::BasicBlock *notNullBB = createBasicBlock("new.notnull");
     contBB = createBasicBlock("new.cont");
 
-    llvm::Value *isNull =
-      Builder.CreateIsNull(allocation.getPointer(), "new.isnull");
+    llvm::Value *isNull = Builder.CreateIsNull(allocation, "new.isnull");
     Builder.CreateCondBr(isNull, contBB, notNullBB);
     EmitBlock(notNullBB);
   }
@@ -1760,12 +1759,12 @@ llvm::Value *CodeGenFunction::EmitCXXNewExpr(const CXXNewExpr *E) {
   SkippedChecks.set(SanitizerKind::Null, nullCheck);
   EmitTypeCheck(CodeGenFunction::TCK_ConstructorCall,
                 E->getAllocatedTypeSourceInfo()->getTypeLoc().getBeginLoc(),
-                result.getPointer(), allocType, result.getAlignment(),
-                SkippedChecks, numElements);
+                result, allocType, result.getAlignment(), SkippedChecks,
+                numElements);
 
   EmitNewInitializer(*this, E, allocType, elementTy, result, numElements,
                      allocSizeWithoutCookie);
-  llvm::Value *resultPtr = result.getPointer();
+  llvm::Value *resultPtr = result.emitRawPointer(*this);
   if (E->isArray()) {
     // NewPtr is a pointer to the base element type.  If we're
     // allocating an array of arrays, we'll need to cast back to the
@@ -1909,7 +1908,8 @@ static void EmitDestroyingObjectDelete(CodeGenFunction &CGF,
     CGF.CGM.getCXXABI().emitVirtualObjectDelete(CGF, DE, Ptr, ElementType,
                                                 Dtor);
   else
-    CGF.EmitDeleteCall(DE->getOperatorDelete(), Ptr.getPointer(), ElementType);
+    CGF.EmitDeleteCall(DE->getOperatorDelete(), Ptr.emitRawPointer(CGF),
+                       ElementType);
 }
 
 /// Emit the code for deleting a single object.
@@ -1925,8 +1925,7 @@ static bool EmitObjectDelete(CodeGenFunction &CGF,
   //   dynamic type, the static type shall be a base class of the dynamic type
   //   of the object to be deleted and the static type shall have a virtual
   //   destructor or the behavior is undefined.
-  CGF.EmitTypeCheck(CodeGenFunction::TCK_MemberCall,
-                    DE->getExprLoc(), Ptr.getPointer(),
+  CGF.EmitTypeCheck(CodeGenFunction::TCK_MemberCall, DE->getExprLoc(), Ptr,
                     ElementType);
 
   const FunctionDecl *OperatorDelete = DE->getOperatorDelete();
@@ -1975,9 +1974,8 @@ static bool EmitObjectDelete(CodeGenFunction &CGF,
   // Make sure that we call delete even if the dtor throws.
   // This doesn't have to a conditional cleanup because we're going
   // to pop it off in a second.
-  CGF.EHStack.pushCleanup<CallObjectDelete>(NormalAndEHCleanup,
-                                            Ptr.getPointer(),
-                                            OperatorDelete, ElementType);
+  CGF.EHStack.pushCleanup<CallObjectDelete>(
+      NormalAndEHCleanup, Ptr.emitRawPointer(CGF), OperatorDelete, ElementType);
 
   if (Dtor)
     CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete,
@@ -2064,7 +2062,7 @@ static void EmitArrayDelete(CodeGenFunction &CGF,
     CharUnits elementAlign =
       deletedPtr.getAlignment().alignmentOfArrayElement(elementSize);
 
-    llvm::Value *arrayBegin = deletedPtr.getPointer();
+    llvm::Value *arrayBegin = deletedPtr.emitRawPointer(CGF);
     llvm::Value *arrayEnd = CGF.Builder.CreateInBoundsGEP(
       deletedPtr.getElementType(), arrayBegin, numElements, "delete.end");
 
@@ -2095,7 +2093,7 @@ void CodeGenFunction::EmitCXXDeleteExpr(const CXXDeleteExpr *E) {
   llvm::BasicBlock *DeleteNotNull = createBasicBlock("delete.notnull");
   llvm::BasicBlock *DeleteEnd = createBasicBlock("delete.end");
 
-  llvm::Value *IsNull = Builder.CreateIsNull(Ptr.getPointer(), "isnull");
+  llvm::Value *IsNull = Builder.CreateIsNull(Ptr, "isnull");
 
   Builder.CreateCondBr(IsNull, DeleteEnd, DeleteNotNull);
   EmitBlock(DeleteNotNull);
@@ -2130,10 +2128,8 @@ void CodeGenFunction::EmitCXXDeleteExpr(const CXXDeleteExpr *E) {
       GEP.push_back(Zero);
     }
 
-    Ptr = Address(Builder.CreateInBoundsGEP(Ptr.getElementType(),
-                                            Ptr.getPointer(), GEP, "del.first"),
-                  ConvertTypeForMem(DeleteTy), Ptr.getAlignment(),
-                  Ptr.isKnownNonNull());
+    Ptr = Builder.CreateInBoundsGEP(Ptr, GEP, ConvertTypeForMem(DeleteTy),
+                                    Ptr.getAlignment(), "del.first");
   }
 
   assert(ConvertTypeForMem(DeleteTy) == Ptr.getElementType());
@@ -2191,7 +2187,7 @@ static llvm::Value *EmitTypeidFromVTable(CodeGenFunction &CGF, const Expr *E,
   //   destruction and the static type of the operand is neither the constructor
   //   or destructor’s class nor one of its bases, the behavior is undefined.
   CGF.EmitTypeCheck(CodeGenFunction::TCK_DynamicOperation, E->getExprLoc(),
-                    ThisPtr.getPointer(), SrcRecordTy);
+                    ThisPtr, SrcRecordTy);
 
   // C++ [expr.typeid]p2:
   //   If the glvalue expression is obtained by applying the unary * operator to
@@ -2207,7 +2203,7 @@ static llvm::Value *EmitTypeidFromVTable(CodeGenFunction &CGF, const Expr *E,
         CGF.createBasicBlock("typeid.bad_typeid");
     llvm::BasicBlock *EndBlock = CGF.createBasicBlock("typeid.end");
 
-    llvm::Value *IsNull = CGF.Builder.CreateIsNull(ThisPtr.getPointer());
+    llvm::Value *IsNull = CGF.Builder.CreateIsNull(ThisPtr);
     CGF.Builder.CreateCondBr(IsNull, BadTypeidBlock, EndBlock);
 
     CGF.EmitBlock(BadTypeidBlock);
@@ -2293,8 +2289,7 @@ llvm::Value *CodeGenFunction::EmitDynamicCast(Address ThisAddr,
   //   construction or destruction and the static type of the operand is not a
   //   pointer to or object of the constructor or destructor’s own class or one
   //   of its bases, the dynamic_cast results in undefined behavior.
-  EmitTypeCheck(TCK_DynamicOperation, DCE->getExprLoc(), ThisAddr.getPointer(),
-                SrcRecordTy);
+  EmitTypeCheck(TCK_DynamicOperation, DCE->getExprLoc(), ThisAddr, SrcRecordTy);
 
   if (DCE->isAlwaysNull()) {
     if (llvm::Value *T = EmitDynamicCastToNull(*this, DestTy)) {
@@ -2329,7 +2324,7 @@ llvm::Value *CodeGenFunction::EmitDynamicCast(Address ThisAddr,
     CastNull = createBasicBlock("dynamic_cast.null");
     CastNotNull = createBasicBlock("dynamic_cast.notnull");
 
-    llvm::Value *IsNull = Builder.CreateIsNull(ThisAddr.getPointer());
+    llvm::Value *IsNull = Builder.CreateIsNull(ThisAddr);
     Builder.CreateCondBr(IsNull, CastNull, CastNotNull);
     EmitBlock(CastNotNull);
   }