[opaque pointer types] Fix the CallInfo passed to EmitCall in some

edge cases.

Currently, EmitCall emits a call instruction with a function type
derived from the pointee-type of the callee. This *should* be the same
as the type created from the CallInfo parameter, but in some cases an
incorrect CallInfo was being passed.

All of these fixes were discovered by the addition of the assert in
EmitCall which verifies that the passed-in CallInfo matches the
Callee's function type.

As far as I know, these issues caused no bugs at the moment, as the
correct types were ultimately being emitted. But, some would become
problematic when pointee types are removed.

List of fixes:

* arrangeCXXConstructorCall was passing an incorrect value for the
  number of Required args, when calling an inheriting constructor
  where the inherited constructor is variadic. (The inheriting
  constructor doesn't actually get passed any of the user's args, but
  the code was calculating it as if it did).

* arrangeFreeFunctionLikeCall was not including the count of the
  pass_object_size arguments in the count of required args.

* OpenCL uses other address spaces for the "this" pointer. However,
  commonEmitCXXMemberOrOperatorCall was not annotating the address
  space on the "this" argument of the call.

* Destructor calls were being created with EmitCXXMemberOrOperatorCall
  instead of EmitCXXDestructorCall in a few places. This was a problem
  because the calling convention sometimes has destructors returning
  "this" rather than void, and the latter function knows about that,
  and sets up the types properly (through calling
  arrangeCXXStructorDeclaration), while the former does not.

* generateObjCGetterBody: the 'objc_getProperty' function returns type
  'id', but was being called as if it returned the particular
  property's type. (That is of course the *dynamic* return type, and
  there's a downcast immediately after.)

* OpenMP user-defined reduction functions (#pragma omp declare
  reduction) can be called with a subclass of the declared type. In
  such case, the call was being setup as if the function had been
  actually declared to take the subtype, rather than the base type.

Differential Revision: https://reviews.llvm.org/D57664

llvm-svn: 353181

7 files changed, 68 insertions, 45 deletions

diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index 2af2379476c..b2dda3c20db 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -67,10 +67,17 @@ unsigned CodeGenTypes::ClangCallConvToLLVMCallConv(CallingConv CC) {
 }
 
 /// Derives the 'this' type for codegen purposes, i.e. ignoring method CVR
-/// qualification.
-static CanQualType GetThisType(ASTContext &Context, const CXXRecordDecl *RD,
-                               const CXXMethodDecl *MD) {
-  QualType RecTy = Context.getTagDeclType(RD)->getCanonicalTypeInternal();
+/// qualification. Either or both of RD and MD may be null. A null RD indicates
+/// that there is no meaningful 'this' type, and a null MD can occur when
+/// calling a method pointer.
+CanQualType CodeGenTypes::DeriveThisType(const CXXRecordDecl *RD,
+                                         const CXXMethodDecl *MD) {
+  QualType RecTy;
+  if (RD)
+    RecTy = Context.getTagDeclType(RD)->getCanonicalTypeInternal();
+  else
+    RecTy = Context.VoidTy;
+
   if (MD)
     RecTy = Context.getAddrSpaceQualType(RecTy, MD->getMethodQualifiers().getAddressSpace());
   return Context.getPointerType(CanQualType::CreateUnsafe(RecTy));
@@ -235,7 +242,7 @@ static CallingConv getCallingConventionForDecl(const Decl *D, bool IsWindows) {
 
 /// Arrange the argument and result information for a call to an
 /// unknown C++ non-static member function of the given abstract type.
-/// (Zero value of RD means we don't have any meaningful "this" argument type,
+/// (A null RD means we don't have any meaningful "this" argument type,
 ///  so fall back to a generic pointer type).
 /// The member function must be an ordinary function, i.e. not a
 /// constructor or destructor.
@@ -246,10 +253,7 @@ CodeGenTypes::arrangeCXXMethodType(const CXXRecordDecl *RD,
   SmallVector<CanQualType, 16> argTypes;
 
   // Add the 'this' pointer.
-  if (RD)
-    argTypes.push_back(GetThisType(Context, RD, MD));
-  else
-    argTypes.push_back(Context.VoidPtrTy);
+  argTypes.push_back(DeriveThisType(RD, MD));
 
   return ::arrangeLLVMFunctionInfo(
       *this, true, argTypes,
@@ -303,7 +307,7 @@ CodeGenTypes::arrangeCXXStructorDeclaration(const CXXMethodDecl *MD,
 
   SmallVector<CanQualType, 16> argTypes;
   SmallVector<FunctionProtoType::ExtParameterInfo, 16> paramInfos;
-  argTypes.push_back(GetThisType(Context, MD->getParent(), MD));
+  argTypes.push_back(DeriveThisType(MD->getParent(), MD));
 
   bool PassParams = true;
 
@@ -403,8 +407,11 @@ CodeGenTypes::arrangeCXXConstructorCall(const CallArgList &args,
   unsigned TotalPrefixArgs = 1 + ExtraPrefixArgs;
 
   CanQual<FunctionProtoType> FPT = GetFormalType(D);
-  RequiredArgs Required =
-      RequiredArgs::forPrototypePlus(FPT, TotalPrefixArgs + ExtraSuffixArgs);
+  RequiredArgs Required = PassProtoArgs
+                              ? RequiredArgs::forPrototypePlus(
+                                    FPT, TotalPrefixArgs + ExtraSuffixArgs)
+                              : RequiredArgs::All;
+
   GlobalDecl GD(D, CtorKind);
   CanQualType ResultType = TheCXXABI.HasThisReturn(GD)
                                ? ArgTypes.front()
@@ -530,7 +537,7 @@ const CGFunctionInfo &
 CodeGenTypes::arrangeUnprototypedMustTailThunk(const CXXMethodDecl *MD) {
   assert(MD->isVirtual() && "only methods have thunks");
   CanQual<FunctionProtoType> FTP = GetFormalType(MD);
-  CanQualType ArgTys[] = { GetThisType(Context, MD->getParent(), MD) };
+  CanQualType ArgTys[] = {DeriveThisType(MD->getParent(), MD)};
   return arrangeLLVMFunctionInfo(Context.VoidTy, /*instanceMethod=*/false,
                                  /*chainCall=*/false, ArgTys,
                                  FTP->getExtInfo(), {}, RequiredArgs(1));
@@ -544,7 +551,7 @@ CodeGenTypes::arrangeMSCtorClosure(const CXXConstructorDecl *CD,
   CanQual<FunctionProtoType> FTP = GetFormalType(CD);
   SmallVector<CanQualType, 2> ArgTys;
   const CXXRecordDecl *RD = CD->getParent();
-  ArgTys.push_back(GetThisType(Context, RD, CD));
+  ArgTys.push_back(DeriveThisType(RD, CD));
   if (CT == Ctor_CopyingClosure)
     ArgTys.push_back(*FTP->param_type_begin());
   if (RD->getNumVBases() > 0)
@@ -577,7 +584,7 @@ arrangeFreeFunctionLikeCall(CodeGenTypes &CGT,
   // extra prefix plus the arguments in the prototype.
   if (const FunctionProtoType *proto = dyn_cast<FunctionProtoType>(fnType)) {
     if (proto->isVariadic())
-      required = RequiredArgs(proto->getNumParams() + numExtraRequiredArgs);
+      required = RequiredArgs::forPrototypePlus(proto, numExtraRequiredArgs);
 
     if (proto->hasExtParameterInfos())
       addExtParameterInfosForCall(paramInfos, proto, numExtraRequiredArgs,
@@ -802,6 +809,8 @@ CGFunctionInfo *CGFunctionInfo::create(unsigned llvmCC,
                                        ArrayRef<CanQualType> argTypes,
                                        RequiredArgs required) {
   assert(paramInfos.empty() || paramInfos.size() == argTypes.size());
+  assert(!required.allowsOptionalArgs() ||
+         required.getNumRequiredArgs() <= argTypes.size());
 
   void *buffer =
     operator new(totalSizeToAlloc<ArgInfo,             ExtParameterInfo>(
@@ -3818,6 +3827,20 @@ RValue CodeGenFunction::EmitCall(const CGFunctionInfo &CallInfo,
 
   llvm::FunctionType *IRFuncTy = Callee.getFunctionType();
 
+#ifndef NDEBUG
+  if (!(CallInfo.isVariadic() && CallInfo.getArgStruct())) {
+    // For an inalloca varargs function, we don't expect CallInfo to match the
+    // function pointer's type, because the inalloca struct a will have extra
+    // fields in it for the varargs parameters.  Code later in this function
+    // bitcasts the function pointer to the type derived from CallInfo.
+    //
+    // In other cases, we assert that the types match up (until pointers stop
+    // having pointee types).
+    llvm::FunctionType *IRFuncTyFromInfo = getTypes().GetFunctionType(CallInfo);
+    assert(IRFuncTy == IRFuncTyFromInfo);
+  }
+#endif
+
   // 1. Set up the arguments.
 
   // If we're using inalloca, insert the allocation after the stack save.
diff --git a/clang/lib/CodeGen/CGExprCXX.cpp b/clang/lib/CodeGen/CGExprCXX.cpp
index 86ec18dbe2a..13612d377c6 100644
--- a/clang/lib/CodeGen/CGExprCXX.cpp
+++ b/clang/lib/CodeGen/CGExprCXX.cpp
@@ -40,13 +40,11 @@ commonEmitCXXMemberOrOperatorCall(CodeGenFunction &CGF, const CXXMethodDecl *MD,
          isa<CXXOperatorCallExpr>(CE));
   assert(MD->isInstance() &&
          "Trying to emit a member or operator call expr on a static method!");
-  ASTContext &C = CGF.getContext();
 
   // Push the this ptr.
   const CXXRecordDecl *RD =
       CGF.CGM.getCXXABI().getThisArgumentTypeForMethod(MD);
-  Args.add(RValue::get(This),
-           RD ? C.getPointerType(C.getTypeDeclType(RD)) : C.VoidPtrTy);
+  Args.add(RValue::get(This), CGF.getTypes().DeriveThisType(RD, MD));
 
   // If there is an implicit parameter (e.g. VTT), emit it.
   if (ImplicitParam) {
@@ -326,9 +324,6 @@ RValue CodeGenFunction::EmitCXXMemberOrOperatorMemberCallExpr(
       CallLoc, This.getPointer(), C.getRecordType(CalleeDecl->getParent()),
       /*Alignment=*/CharUnits::Zero(), SkippedChecks);
 
-  // FIXME: Uses of 'MD' past this point need to be audited. We may need to use
-  // 'CalleeDecl' instead.
-
   // C++ [class.virtual]p12:
   //   Explicit qualification with the scope operator (5.1) suppresses the
   //   virtual call mechanism.
@@ -337,7 +332,7 @@ RValue CodeGenFunction::EmitCXXMemberOrOperatorMemberCallExpr(
   // because then we know what the type is.
   bool UseVirtualCall = CanUseVirtualCall && !DevirtualizedMethod;
 
-  if (const CXXDestructorDecl *Dtor = dyn_cast<CXXDestructorDecl>(MD)) {
+  if (const CXXDestructorDecl *Dtor = dyn_cast<CXXDestructorDecl>(CalleeDecl)) {
     assert(CE->arg_begin() == CE->arg_end() &&
            "Destructor shouldn't have explicit parameters");
     assert(ReturnValue.isNull() && "Destructor shouldn't have return value");
@@ -347,26 +342,29 @@ RValue CodeGenFunction::EmitCXXMemberOrOperatorMemberCallExpr(
           cast<CXXMemberCallExpr>(CE));
     } else {
       CGCallee Callee;
-      if (getLangOpts().AppleKext && MD->isVirtual() && HasQualifier)
-        Callee = BuildAppleKextVirtualCall(MD, Qualifier, Ty);
+      if (getLangOpts().AppleKext && Dtor->isVirtual() && HasQualifier)
+        Callee = BuildAppleKextVirtualCall(Dtor, Qualifier, Ty);
       else if (!DevirtualizedMethod)
         Callee = CGCallee::forDirect(
             CGM.getAddrOfCXXStructor(Dtor, StructorType::Complete, FInfo, Ty),
             GlobalDecl(Dtor, Dtor_Complete));
       else {
-        const CXXDestructorDecl *DDtor =
-          cast<CXXDestructorDecl>(DevirtualizedMethod);
         Callee = CGCallee::forDirect(
-            CGM.GetAddrOfFunction(GlobalDecl(DDtor, Dtor_Complete), Ty),
-            GlobalDecl(DDtor, Dtor_Complete));
+            CGM.GetAddrOfFunction(GlobalDecl(Dtor, Dtor_Complete), Ty),
+            GlobalDecl(Dtor, Dtor_Complete));
       }
-      EmitCXXMemberOrOperatorCall(
-          CalleeDecl, Callee, ReturnValue, This.getPointer(),
-          /*ImplicitParam=*/nullptr, QualType(), CE, nullptr);
+
+      EmitCXXDestructorCall(Dtor, Callee, This.getPointer(),
+                            /*ImplicitParam=*/nullptr,
+                            /*ImplicitParamTy=*/QualType(), nullptr,
+                            getFromDtorType(Dtor_Complete));
     }
     return RValue::get(nullptr);
   }
 
+  // FIXME: Uses of 'MD' past this point need to be audited. We may need to use
+  // 'CalleeDecl' instead.
+
   CGCallee Callee;
   if (const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(MD)) {
     Callee = CGCallee::forDirect(
diff --git a/clang/lib/CodeGen/CGObjC.cpp b/clang/lib/CodeGen/CGObjC.cpp
index 9a212969f4a..b70dab71a60 100644
--- a/clang/lib/CodeGen/CGObjC.cpp
+++ b/clang/lib/CodeGen/CGObjC.cpp
@@ -1051,9 +1051,9 @@ CodeGenFunction::generateObjCGetterBody(const ObjCImplementationDecl *classImpl,
     // FIXME: We shouldn't need to get the function info here, the
     // runtime already should have computed it to build the function.
     llvm::CallBase *CallInstruction;
-    RValue RV = EmitCall(
-        getTypes().arrangeBuiltinFunctionCall(propType, args),
-        callee, ReturnValueSlot(), args, &CallInstruction);
+    RValue RV = EmitCall(getTypes().arrangeBuiltinFunctionCall(
+                             getContext().getObjCIdType(), args),
+                         callee, ReturnValueSlot(), args, &CallInstruction);
     if (llvm::CallInst *call = dyn_cast<llvm::CallInst>(CallInstruction))
       call->setTailCall();
 
diff --git a/clang/lib/CodeGen/CodeGenTypes.h b/clang/lib/CodeGen/CodeGenTypes.h
index d7e6edde831..c5491730cba 100644
--- a/clang/lib/CodeGen/CodeGenTypes.h
+++ b/clang/lib/CodeGen/CodeGenTypes.h
@@ -182,6 +182,10 @@ public:
   /// Convert clang calling convention to LLVM callilng convention.
   unsigned ClangCallConvToLLVMCallConv(CallingConv CC);
 
+  /// Derives the 'this' type for codegen purposes, i.e. ignoring method CVR
+  /// qualification.
+  CanQualType DeriveThisType(const CXXRecordDecl *RD, const CXXMethodDecl *MD);
+
   /// ConvertType - Convert type T into a llvm::Type.
   llvm::Type *ConvertType(QualType T);
 
diff --git a/clang/lib/CodeGen/ItaniumCXXABI.cpp b/clang/lib/CodeGen/ItaniumCXXABI.cpp
index 453bd2faa7e..073857699c8 100644
--- a/clang/lib/CodeGen/ItaniumCXXABI.cpp
+++ b/clang/lib/CodeGen/ItaniumCXXABI.cpp
@@ -1566,9 +1566,8 @@ void ItaniumCXXABI::EmitDestructorCall(CodeGenFunction &CGF,
     Callee = CGCallee::forDirect(
         CGM.getAddrOfCXXStructor(DD, getFromDtorType(Type)), GD);
 
-  CGF.EmitCXXMemberOrOperatorCall(DD, Callee, ReturnValueSlot(),
-                                  This.getPointer(), VTT, VTTTy,
-                                  nullptr, nullptr);
+  CGF.EmitCXXDestructorCall(DD, Callee, This.getPointer(), VTT, VTTTy, nullptr,
+                            getFromDtorType(Type));
 }
 
 void ItaniumCXXABI::emitVTableDefinitions(CodeGenVTables &CGVT,
@@ -1766,9 +1765,8 @@ llvm::Value *ItaniumCXXABI::EmitVirtualDestructorCall(
   CGCallee Callee =
       CGCallee::forVirtual(CE, GlobalDecl(Dtor, DtorType), This, Ty);
 
-  CGF.EmitCXXMemberOrOperatorCall(Dtor, Callee, ReturnValueSlot(),
-                                  This.getPointer(), /*ImplicitParam=*/nullptr,
-                                  QualType(), CE, nullptr);
+  CGF.EmitCXXDestructorCall(Dtor, Callee, This.getPointer(), nullptr,
+                            QualType(), nullptr, getFromDtorType(DtorType));
   return nullptr;
 }
 
diff --git a/clang/lib/Sema/SemaOpenMP.cpp b/clang/lib/Sema/SemaOpenMP.cpp
index 6716329e26a..5ee5eb0b6bf 100644
--- a/clang/lib/Sema/SemaOpenMP.cpp
+++ b/clang/lib/Sema/SemaOpenMP.cpp
@@ -10747,7 +10747,8 @@ buildDeclareReductionRef(Sema &SemaRef, SourceLocation Loc, SourceRange Range,
               return D;
             return nullptr;
           }))
-    return SemaRef.BuildDeclRefExpr(VD, Ty, VK_LValue, Loc);
+    return SemaRef.BuildDeclRefExpr(VD, VD->getType().getNonReferenceType(),
+                                    VK_LValue, Loc);
   if (auto *VD = filterLookupForUDR<ValueDecl *>(
           Lookups, [&SemaRef, Ty, Loc](ValueDecl *D) -> ValueDecl * {
             if (!D->isInvalidDecl() &&
@@ -10765,7 +10766,8 @@ buildDeclareReductionRef(Sema &SemaRef, SourceLocation Loc, SourceRange Range,
                                          /*DiagID=*/0) !=
             Sema::AR_inaccessible) {
           SemaRef.BuildBasePathArray(Paths, BasePath);
-          return SemaRef.BuildDeclRefExpr(VD, Ty, VK_LValue, Loc);
+          return SemaRef.BuildDeclRefExpr(
+              VD, VD->getType().getNonReferenceType(), VK_LValue, Loc);
         }
       }
     }
diff --git a/clang/test/CodeGenObjC/getter-property-mismatch.m b/clang/test/CodeGenObjC/getter-property-mismatch.m
index fe415d5358d..cc54fa65196 100644
--- a/clang/test/CodeGenObjC/getter-property-mismatch.m
+++ b/clang/test/CodeGenObjC/getter-property-mismatch.m
@@ -15,6 +15,4 @@
 
 // CHECK:  [[CALL:%.*]] = tail call i8* @objc_getProperty
 // CHECK:  [[ONE:%.*]] = bitcast i8* [[CALL:%.*]] to [[T1:%.*]]*
-// CHECK:  [[TWO:%.*]] = bitcast [[T1]]* [[ONE]] to [[T2:%.*]]*
-// CHECK:  ret [[T2]]* [[TWO]]
-
+// CHECK:  ret [[T1]]* [[ONE]]