[clang][CGObjCMac] Remove no-op ptr-to-ptr bitcasts (NFC)

Opaque ptr cleanup effort (NFC).

Author: JOE1994

clang/lib/CodeGen/CGObjCMac.cpp

@@ -2961,8 +2961,7 @@ llvm::Value *CGObjCMac::GenerateProtocolRef(CodeGenFunction &CGF,
   // resolved. Investigate. Its also wasteful to look this up over and over.
   LazySymbols.insert(&CGM.getContext().Idents.get("Protocol"));
 
-  return llvm::ConstantExpr::getBitCast(GetProtocolRef(PD),
-                                        ObjCTypes.getExternalProtocolPtrTy());
+  return GetProtocolRef(PD);
 }
 
 void CGObjCCommonMac::GenerateProtocol(const ObjCProtocolDecl *PD) {
@@ -3182,7 +3181,7 @@ CGObjCMac::EmitProtocolList(Twine name,
 
   llvm::GlobalVariable *GV =
       CreateMetadataVar(name, values, section, CGM.getPointerAlign(), false);
-  return llvm::ConstantExpr::getBitCast(GV, ObjCTypes.ProtocolListPtrTy);
+  return GV;
 }
 
 static void
@@ -3290,7 +3289,7 @@ llvm::Constant *CGObjCCommonMac::EmitPropertyList(Twine Name,
 
   llvm::GlobalVariable *GV =
       CreateMetadataVar(Name, values, Section, CGM.getPointerAlign(), true);
-  return llvm::ConstantExpr::getBitCast(GV, ObjCTypes.PropertyListPtrTy);
+  return GV;
 }
 
 llvm::Constant *
@@ -3311,7 +3310,7 @@ CGObjCCommonMac::EmitProtocolMethodTypes(Twine Name,
 
   llvm::GlobalVariable *GV =
       CreateMetadataVar(Name, Init, Section, CGM.getPointerAlign(), true);
-  return llvm::ConstantExpr::getBitCast(GV, ObjCTypes.Int8PtrPtrTy);
+  return GV;
 }
 
 /*
@@ -3804,7 +3803,7 @@ llvm::Constant *CGObjCMac::EmitIvarList(const ObjCImplementationDecl *ID,
   GV = CreateMetadataVar("OBJC_INSTANCE_VARIABLES_" + ID->getName(), ivarList,
                          "__OBJC,__instance_vars,regular,no_dead_strip",
                          CGM.getPointerAlign(), true);
-  return llvm::ConstantExpr::getBitCast(GV, ObjCTypes.IvarListPtrTy);
+  return GV;
 }
 
 /// Build a struct objc_method_description constant for the given method.
@@ -3923,8 +3922,7 @@ llvm::Constant *CGObjCMac::emitMethodList(Twine name, MethodListType MLT,
 
     llvm::GlobalVariable *GV = CreateMetadataVar(prefix + name, values, section,
                                                  CGM.getPointerAlign(), true);
-    return llvm::ConstantExpr::getBitCast(GV,
-                                          ObjCTypes.MethodDescriptionListPtrTy);
+    return GV;
   }
 
   // Otherwise, it's an objc_method_list.
@@ -3941,7 +3939,7 @@ llvm::Constant *CGObjCMac::emitMethodList(Twine name, MethodListType MLT,
 
   llvm::GlobalVariable *GV = CreateMetadataVar(prefix + name, values, section,
                                                CGM.getPointerAlign(), true);
-  return llvm::ConstantExpr::getBitCast(GV, ObjCTypes.MethodListPtrTy);
+  return GV;
 }
 
 llvm::Function *CGObjCCommonMac::GenerateMethod(const ObjCMethodDecl *OMD,
@@ -3996,8 +3994,7 @@ CGObjCCommonMac::GenerateDirectMethod(const ObjCMethodDecl *OMD,
     Fn = llvm::Function::Create(MethodTy, llvm::GlobalValue::ExternalLinkage,
                                 "", &CGM.getModule());
     Fn->takeName(OldFn);
-    OldFn->replaceAllUsesWith(
-        llvm::ConstantExpr::getBitCast(Fn, OldFn->getType()));
+    OldFn->replaceAllUsesWith(Fn);
     OldFn->eraseFromParent();
 
     // Replace the cached function in the map.
@@ -5204,7 +5201,7 @@ llvm::Constant *CGObjCMac::EmitModuleSymbols() {
   llvm::GlobalVariable *GV = CreateMetadataVar(
       "OBJC_SYMBOLS", values, "__OBJC,__symbols,regular,no_dead_strip",
       CGM.getPointerAlign(), true);
-  return llvm::ConstantExpr::getBitCast(GV, ObjCTypes.SymtabPtrTy);
+  return GV;
 }
 
 llvm::Value *CGObjCMac::EmitClassRefFromId(CodeGenFunction &CGF,
@@ -5214,13 +5211,10 @@ llvm::Value *CGObjCMac::EmitClassRefFromId(CodeGenFunction &CGF,
   llvm::GlobalVariable *&Entry = ClassReferences[II];
 
   if (!Entry) {
-    llvm::Constant *Casted =
-    llvm::ConstantExpr::getBitCast(GetClassName(II->getName()),
-                                   ObjCTypes.ClassPtrTy);
-    Entry = CreateMetadataVar(
-        "OBJC_CLASS_REFERENCES_", Casted,
-        "__OBJC,__cls_refs,literal_pointers,no_dead_strip",
-        CGM.getPointerAlign(), true);
+    Entry =
+        CreateMetadataVar("OBJC_CLASS_REFERENCES_", GetClassName(II->getName()),
+                          "__OBJC,__cls_refs,literal_pointers,no_dead_strip",
+                          CGM.getPointerAlign(), true);
   }
 
   return CGF.Builder.CreateAlignedLoad(Entry->getValueType(), Entry,
@@ -5253,11 +5247,8 @@ Address CGObjCMac::EmitSelectorAddr(Selector Sel) {
 
   llvm::GlobalVariable *&Entry = SelectorReferences[Sel];
   if (!Entry) {
-    llvm::Constant *Casted =
-      llvm::ConstantExpr::getBitCast(GetMethodVarName(Sel),
-                                     ObjCTypes.SelectorPtrTy);
     Entry = CreateMetadataVar(
-        "OBJC_SELECTOR_REFERENCES_", Casted,
+        "OBJC_SELECTOR_REFERENCES_", GetMethodVarName(Sel),
         "__OBJC,__message_refs,literal_pointers,no_dead_strip", Align, true);
     Entry->setExternallyInitialized(true);
   }
@@ -6166,8 +6157,8 @@ void CGObjCNonFragileABIMac::AddModuleClassList(
 
   SmallVector<llvm::Constant*, 8> Symbols(NumClasses);
   for (unsigned i=0; i<NumClasses; i++)
-    Symbols[i] = llvm::ConstantExpr::getBitCast(Container[i],
-                                                ObjCTypes.Int8PtrTy);
+    Symbols[i] = Container[i];
+
   llvm::Constant *Init =
     llvm::ConstantArray::get(llvm::ArrayType::get(ObjCTypes.Int8PtrTy,
                                                   Symbols.size()),
@@ -6603,9 +6594,7 @@ llvm::Value *CGObjCNonFragileABIMac::GenerateProtocolRef(CodeGenFunction &CGF,
   // of protocol's meta-data (not a reference to it!)
   assert(!PD->isNonRuntimeProtocol() &&
          "attempting to get a protocol ref to a static protocol.");
-  llvm::Constant *Init =
-    llvm::ConstantExpr::getBitCast(GetOrEmitProtocol(PD),
-                                   ObjCTypes.getExternalProtocolPtrTy());
+  llvm::Constant *Init = GetOrEmitProtocol(PD);
 
   std::string ProtocolName("_OBJC_PROTOCOL_REFERENCE_$_");
   ProtocolName += PD->getObjCRuntimeNameAsString();
@@ -6830,7 +6819,7 @@ CGObjCNonFragileABIMac::emitMethodList(Twine name, MethodListType kind,
 
   llvm::GlobalVariable *GV = finishAndCreateGlobal(values, prefix + name, CGM);
   CGM.addCompilerUsedGlobal(GV);
-  return llvm::ConstantExpr::getBitCast(GV, ObjCTypes.MethodListnfABIPtrTy);
+  return GV;
 }
 
 /// ObjCIvarOffsetVariable - Returns the ivar offset variable for
@@ -6972,7 +6961,7 @@ llvm::Constant *CGObjCNonFragileABIMac::EmitIvarList(
   llvm::GlobalVariable *GV = finishAndCreateGlobal(
       ivarList, Prefix + OID->getObjCRuntimeNameAsString(), CGM);
   CGM.addCompilerUsedGlobal(GV);
-  return llvm::ConstantExpr::getBitCast(GV, ObjCTypes.IvarListnfABIPtrTy);
+  return GV;
 }
 
 llvm::Constant *CGObjCNonFragileABIMac::GetOrEmitProtocolRef(
@@ -7146,7 +7135,7 @@ CGObjCNonFragileABIMac::EmitProtocolList(Twine Name,
   llvm::GlobalVariable *GV =
     CGM.getModule().getGlobalVariable(TmpName.str(), true);
   if (GV)
-    return llvm::ConstantExpr::getBitCast(GV, ObjCTypes.ProtocolListnfABIPtrTy);
+    return GV;
 
   ConstantInitBuilder builder(CGM);
   auto values = builder.beginStruct();
@@ -7164,8 +7153,7 @@ CGObjCNonFragileABIMac::EmitProtocolList(Twine Name,
 
   GV = finishAndCreateGlobal(values, Name, CGM);
   CGM.addCompilerUsedGlobal(GV);
-  return llvm::ConstantExpr::getBitCast(GV,
-                                        ObjCTypes.ProtocolListnfABIPtrTy);
+  return GV;
 }
 
 /// EmitObjCValueForIvar - Code Gen for nonfragile ivar reference.
@@ -7399,8 +7387,7 @@ CGObjCNonFragileABIMac::GetClassGlobal(StringRef Name,
       NewGV->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
 
     if (GV) {
-      GV->replaceAllUsesWith(
-          llvm::ConstantExpr::getBitCast(NewGV, GV->getType()));
+      GV->replaceAllUsesWith(NewGV);
       GV->eraseFromParent();
     }
     GV = NewGV;
@@ -7611,14 +7598,11 @@ Address CGObjCNonFragileABIMac::EmitSelectorAddr(Selector Sel) {
   llvm::GlobalVariable *&Entry = SelectorReferences[Sel];
   CharUnits Align = CGM.getPointerAlign();
   if (!Entry) {
-    llvm::Constant *Casted =
-      llvm::ConstantExpr::getBitCast(GetMethodVarName(Sel),
-                                     ObjCTypes.SelectorPtrTy);
     std::string SectionName =
         GetSectionName("__objc_selrefs", "literal_pointers,no_dead_strip");
     Entry = new llvm::GlobalVariable(
         CGM.getModule(), ObjCTypes.SelectorPtrTy, false,
-        getLinkageTypeForObjCMetadata(CGM, SectionName), Casted,
+        getLinkageTypeForObjCMetadata(CGM, SectionName), GetMethodVarName(Sel),
         "OBJC_SELECTOR_REFERENCES_");
     Entry->setExternallyInitialized(true);
     Entry->setSection(SectionName);