r287437 - Introduce a helper class for building complex constant initializers. NFC.

Galina Kistanova via cfe-commits cfe-commits at lists.llvm.org
Mon Nov 21 15:01:44 PST 2016


This revision also added few warning to this builder:
http://lab.llvm.org:8011/builders/clang-3stage-ubuntu/builds/388

/home/buildbot/Buildbot/Slave1a/clang-3stage-ubuntu/llvm.src/tools/clang/lib/CodeGen/CGBlocks.cpp:193:23:
warning: unused variable 'BlockHeaderSize' [-Wunused-const-variable]
1 warning generated.
/home/buildbot/Buildbot/Slave1a/clang-3stage-ubuntu/llvm.src/tools/clang/lib/CodeGen/CGBlocks.cpp:193:23:
warning: unused variable 'BlockHeaderSize' [-Wunused-const-variable]
1 warning generated.

Please have a look at this?

Thanks

Galina

On Sat, Nov 19, 2016 at 4:11 PM, Galina Kistanova <gkistanova at gmail.com>
wrote:

> Thanks, John!
> That fixed the problem.
>
>
> Thanks
>
> Galina
>
> On Sat, Nov 19, 2016 at 1:22 PM, John McCall <rjmccall at apple.com> wrote:
>
>>
>> On Nov 19, 2016, at 1:06 PM, Galina Kistanova <gkistanova at gmail.com>
>> wrote:
>>
>> Hello John,
>>
>> This change has introduced alignment problems for some variables.
>>
>> The build bots are broken.
>> http://lab.llvm.org:8011/builders/clang-3stage-ubuntu/builds/355
>> http://lab.llvm.org:8011/builders/clang-with-lto-ubuntu/builds/308
>>
>> Could you take care of the issue, please?
>>
>>
>> Please let me know if r287458 fixes the problem.
>>
>> John.
>>
>>
>> Thanks
>>
>> Galina
>>
>>
>>
>> On Sat, Nov 19, 2016 at 12:17 AM, John McCall via cfe-commits <
>> cfe-commits at lists.llvm.org> wrote:
>>
>>> Author: rjmccall
>>> Date: Sat Nov 19 02:17:24 2016
>>> New Revision: 287437
>>>
>>> URL: http://llvm.org/viewvc/llvm-project?rev=287437&view=rev
>>> Log:
>>> Introduce a helper class for building complex constant initializers.
>>> NFC.
>>>
>>> I've adopted this in most of the places it makes sense, but v-tables
>>> and CGObjCMac will need a second pass.
>>>
>>> Added:
>>>     cfe/trunk/lib/CodeGen/ConstantBuilder.h
>>> Modified:
>>>     cfe/trunk/include/clang/AST/DeclObjC.h
>>>     cfe/trunk/lib/CodeGen/CGBlocks.cpp
>>>     cfe/trunk/lib/CodeGen/CGCUDANV.cpp
>>>     cfe/trunk/lib/CodeGen/CGObjCGNU.cpp
>>>     cfe/trunk/lib/CodeGen/CGOpenMPRuntime.cpp
>>>     cfe/trunk/lib/CodeGen/CodeGenModule.cpp
>>>
>>> Modified: cfe/trunk/include/clang/AST/DeclObjC.h
>>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/
>>> AST/DeclObjC.h?rev=287437&r1=287436&r2=287437&view=diff
>>> ============================================================
>>> ==================
>>> --- cfe/trunk/include/clang/AST/DeclObjC.h (original)
>>> +++ cfe/trunk/include/clang/AST/DeclObjC.h Sat Nov 19 02:17:24 2016
>>> @@ -870,6 +870,9 @@ public:
>>>    PropertyControl getPropertyImplementation() const {
>>>      return PropertyControl(PropertyImplementation);
>>>    }
>>> +  bool isOptional() const {
>>> +    return getPropertyImplementation() == PropertyControl::Optional;
>>> +  }
>>>
>>>    void setPropertyIvarDecl(ObjCIvarDecl *Ivar) {
>>>      PropertyIvarDecl = Ivar;
>>>
>>> Modified: cfe/trunk/lib/CodeGen/CGBlocks.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CG
>>> Blocks.cpp?rev=287437&r1=287436&r2=287437&view=diff
>>> ============================================================
>>> ==================
>>> --- cfe/trunk/lib/CodeGen/CGBlocks.cpp (original)
>>> +++ cfe/trunk/lib/CodeGen/CGBlocks.cpp Sat Nov 19 02:17:24 2016
>>> @@ -16,6 +16,7 @@
>>>  #include "CGObjCRuntime.h"
>>>  #include "CodeGenFunction.h"
>>>  #include "CodeGenModule.h"
>>> +#include "ConstantBuilder.h"
>>>  #include "clang/AST/DeclObjC.h"
>>>  #include "llvm/ADT/SmallSet.h"
>>>  #include "llvm/IR/CallSite.h"
>>> @@ -77,63 +78,63 @@ static llvm::Constant *buildBlockDescrip
>>>                                              const CGBlockInfo
>>> &blockInfo) {
>>>    ASTContext &C = CGM.getContext();
>>>
>>> -  llvm::Type *ulong = CGM.getTypes().ConvertType(C.UnsignedLongTy);
>>> -  llvm::Type *i8p = nullptr;
>>> +  llvm::IntegerType *ulong =
>>> +    cast<llvm::IntegerType>(CGM.getTypes().ConvertType(C.Unsigne
>>> dLongTy));
>>> +  llvm::PointerType *i8p = nullptr;
>>>    if (CGM.getLangOpts().OpenCL)
>>>      i8p =
>>>        llvm::Type::getInt8PtrTy(
>>>             CGM.getLLVMContext(), C.getTargetAddressSpace(LangAS
>>> ::opencl_constant));
>>>    else
>>> -    i8p = CGM.getTypes().ConvertType(C.VoidPtrTy);
>>> +    i8p = CGM.VoidPtrTy;
>>>
>>> -  SmallVector<llvm::Constant*, 6> elements;
>>> +  ConstantBuilder builder(CGM);
>>> +  auto elements = builder.beginStruct();
>>>
>>>    // reserved
>>> -  elements.push_back(llvm::ConstantInt::get(ulong, 0));
>>> +  elements.addInt(ulong, 0);
>>>
>>>    // Size
>>>    // FIXME: What is the right way to say this doesn't fit?  We should
>>> give
>>>    // a user diagnostic in that case.  Better fix would be to change the
>>>    // API to size_t.
>>> -  elements.push_back(llvm::ConstantInt::get(ulong,
>>> -
>>> blockInfo.BlockSize.getQuantity()));
>>> +  elements.addInt(ulong, blockInfo.BlockSize.getQuantity());
>>>
>>>    // Optional copy/dispose helpers.
>>>    if (blockInfo.NeedsCopyDispose) {
>>>      // copy_func_helper_decl
>>> -    elements.push_back(buildCopyHelper(CGM, blockInfo));
>>> +    elements.add(buildCopyHelper(CGM, blockInfo));
>>>
>>>      // destroy_func_decl
>>> -    elements.push_back(buildDisposeHelper(CGM, blockInfo));
>>> +    elements.add(buildDisposeHelper(CGM, blockInfo));
>>>    }
>>>
>>>    // Signature.  Mandatory ObjC-style method descriptor @encode
>>> sequence.
>>>    std::string typeAtEncoding =
>>>      CGM.getContext().getObjCEncodingForBlock(blockInfo.getBlockExpr());
>>> -  elements.push_back(llvm::ConstantExpr::getBitCast(
>>> +  elements.add(llvm::ConstantExpr::getBitCast(
>>>      CGM.GetAddrOfConstantCString(typeAtEncoding).getPointer(), i8p));
>>>
>>>    // GC layout.
>>>    if (C.getLangOpts().ObjC1) {
>>>      if (CGM.getLangOpts().getGC() != LangOptions::NonGC)
>>> -      elements.push_back(CGM.getObjCRuntime().BuildGCBlockLayout(CGM,
>>> blockInfo));
>>> +      elements.add(CGM.getObjCRuntime().BuildGCBlockLayout(CGM,
>>> blockInfo));
>>>      else
>>> -      elements.push_back(CGM.getObjCRuntime().BuildRCBlockLayout(CGM,
>>> blockInfo));
>>> +      elements.add(CGM.getObjCRuntime().BuildRCBlockLayout(CGM,
>>> blockInfo));
>>>    }
>>>    else
>>> -    elements.push_back(llvm::Constant::getNullValue(i8p));
>>> -
>>> -  llvm::Constant *init = llvm::ConstantStruct::getAnon(elements);
>>> +    elements.addNullPointer(i8p);
>>>
>>>    unsigned AddrSpace = 0;
>>>    if (C.getLangOpts().OpenCL)
>>>      AddrSpace = C.getTargetAddressSpace(LangAS::opencl_constant);
>>> +
>>>    llvm::GlobalVariable *global =
>>> -    new llvm::GlobalVariable(CGM.getModule(), init->getType(), true,
>>> -                             llvm::GlobalValue::InternalLinkage,
>>> -                             init, "__block_descriptor_tmp", nullptr,
>>> -                             llvm::GlobalValue::NotThreadLocal,
>>> -                             AddrSpace);
>>> +    elements.finishAndCreateGlobal("__block_descriptor_tmp",
>>> +                                   CGM.getPointerAlign(),
>>> +                                   /*constant*/ true,
>>> +                                   llvm::GlobalValue::InternalLinkage,
>>> +                                   AddrSpace);
>>>
>>>    return llvm::ConstantExpr::getBitCast(global,
>>> CGM.getBlockDescriptorType());
>>>  }
>>> @@ -1080,36 +1081,31 @@ static llvm::Constant *buildGlobalBlock(
>>>    assert(blockInfo.CanBeGlobal);
>>>
>>>    // Generate the constants for the block literal initializer.
>>> -  llvm::Constant *fields[BlockHeaderSize];
>>> +  ConstantBuilder builder(CGM);
>>> +  auto fields = builder.beginStruct();
>>>
>>>    // isa
>>> -  fields[0] = CGM.getNSConcreteGlobalBlock();
>>> +  fields.add(CGM.getNSConcreteGlobalBlock());
>>>
>>>    // __flags
>>>    BlockFlags flags = BLOCK_IS_GLOBAL | BLOCK_HAS_SIGNATURE;
>>>    if (blockInfo.UsesStret) flags |= BLOCK_USE_STRET;
>>>
>>> -  fields[1] = llvm::ConstantInt::get(CGM.IntTy, flags.getBitMask());
>>> +  fields.addInt(CGM.IntTy, flags.getBitMask());
>>>
>>>    // Reserved
>>> -  fields[2] = llvm::Constant::getNullValue(CGM.IntTy);
>>> +  fields.addInt(CGM.IntTy, 0);
>>>
>>>    // Function
>>> -  fields[3] = blockFn;
>>> +  fields.add(blockFn);
>>>
>>>    // Descriptor
>>> -  fields[4] = buildBlockDescriptor(CGM, blockInfo);
>>> -
>>> -  llvm::Constant *init = llvm::ConstantStruct::getAnon(fields);
>>> +  fields.add(buildBlockDescriptor(CGM, blockInfo));
>>>
>>> -  llvm::GlobalVariable *literal =
>>> -    new llvm::GlobalVariable(CGM.getModule(),
>>> -                             init->getType(),
>>> -                             /*constant*/ true,
>>> -                             llvm::GlobalVariable::InternalLinkage,
>>> -                             init,
>>> -                             "__block_literal_global");
>>> -  literal->setAlignment(blockInfo.BlockAlign.getQuantity());
>>> +  llvm::Constant *literal =
>>> +    fields.finishAndCreateGlobal("__block_literal_global",
>>> +                                 blockInfo.BlockAlign,
>>> +                                 /*constant*/ true);
>>>
>>>    // Return a constant of the appropriately-casted type.
>>>    llvm::Type *requiredType =
>>>
>>> Modified: cfe/trunk/lib/CodeGen/CGCUDANV.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CG
>>> CUDANV.cpp?rev=287437&r1=287436&r2=287437&view=diff
>>> ============================================================
>>> ==================
>>> --- cfe/trunk/lib/CodeGen/CGCUDANV.cpp (original)
>>> +++ cfe/trunk/lib/CodeGen/CGCUDANV.cpp Sat Nov 19 02:17:24 2016
>>> @@ -15,6 +15,7 @@
>>>  #include "CGCUDARuntime.h"
>>>  #include "CodeGenFunction.h"
>>>  #include "CodeGenModule.h"
>>> +#include "ConstantBuilder.h"
>>>  #include "clang/AST/Decl.h"
>>>  #include "llvm/IR/BasicBlock.h"
>>>  #include "llvm/IR/CallSite.h"
>>> @@ -29,7 +30,8 @@ namespace {
>>>  class CGNVCUDARuntime : public CGCUDARuntime {
>>>
>>>  private:
>>> -  llvm::Type *IntTy, *SizeTy, *VoidTy;
>>> +  llvm::IntegerType *IntTy, *SizeTy;
>>> +  llvm::Type *VoidTy;
>>>    llvm::PointerType *CharPtrTy, *VoidPtrTy, *VoidPtrPtrTy;
>>>
>>>    /// Convenience reference to LLVM Context
>>> @@ -95,9 +97,9 @@ CGNVCUDARuntime::CGNVCUDARuntime(CodeGen
>>>    CodeGen::CodeGenTypes &Types = CGM.getTypes();
>>>    ASTContext &Ctx = CGM.getContext();
>>>
>>> -  IntTy = Types.ConvertType(Ctx.IntTy);
>>> -  SizeTy = Types.ConvertType(Ctx.getSizeType());
>>> -  VoidTy = llvm::Type::getVoidTy(Context);
>>> +  IntTy = CGM.IntTy;
>>> +  SizeTy = CGM.SizeTy;
>>> +  VoidTy = CGM.VoidTy;
>>>
>>>    CharPtrTy = llvm::PointerType::getUnqual(T
>>> ypes.ConvertType(Ctx.CharTy));
>>>    VoidPtrTy = cast<llvm::PointerType>(Types.
>>> ConvertType(Ctx.VoidPtrTy));
>>> @@ -296,16 +298,21 @@ llvm::Function *CGNVCUDARuntime::makeMod
>>>          CGM.getTriple().isMacOSX() ? "__NV_CUDA,__fatbin" :
>>> ".nvFatBinSegment";
>>>
>>>      // Create initialized wrapper structure that points to the loaded
>>> GPU binary
>>> -    llvm::Constant *Values[] = {
>>> -        llvm::ConstantInt::get(IntTy, 0x466243b1), // Fatbin wrapper
>>> magic.
>>> -        llvm::ConstantInt::get(IntTy, 1),          // Fatbin version.
>>> -        makeConstantString(GpuBinaryOrErr.get()->getBuffer(), // Data.
>>> -                           "", FatbinConstantName, 8),
>>> -        llvm::ConstantPointerNull::get(VoidPtrTy)}; // Unused in
>>> fatbin v1.
>>> -    llvm::GlobalVariable *FatbinWrapper = new llvm::GlobalVariable(
>>> -        TheModule, FatbinWrapperTy, true, llvm::GlobalValue::InternalLin
>>> kage,
>>> -        llvm::ConstantStruct::get(FatbinWrapperTy, Values),
>>> -        "__cuda_fatbin_wrapper");
>>> +    ConstantBuilder Builder(CGM);
>>> +    auto Values = Builder.beginStruct(FatbinWrapperTy);
>>> +    // Fatbin wrapper magic.
>>> +    Values.addInt(IntTy, 0x466243b1);
>>> +    // Fatbin version.
>>> +    Values.addInt(IntTy, 1);
>>> +    // Data.
>>> +    Values.add(makeConstantString(GpuBinaryOrErr.get()->getBuffer(),
>>> +                                  "", FatbinConstantName, 8));
>>> +    // Unused in fatbin v1.
>>> +    Values.add(llvm::ConstantPointerNull::get(VoidPtrTy));
>>> +    llvm::GlobalVariable *FatbinWrapper =
>>> +      Values.finishAndCreateGlobal("__cuda_fatbin_wrapper",
>>> +                                   CGM.getPointerAlign(),
>>> +                                   /*constant*/ true);
>>>      FatbinWrapper->setSection(FatbinSectionName);
>>>
>>>      // GpuBinaryHandle = __cudaRegisterFatBinary(&FatbinWrapper);
>>>
>>> Modified: cfe/trunk/lib/CodeGen/CGObjCGNU.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CG
>>> ObjCGNU.cpp?rev=287437&r1=287436&r2=287437&view=diff
>>> ============================================================
>>> ==================
>>> --- cfe/trunk/lib/CodeGen/CGObjCGNU.cpp (original)
>>> +++ cfe/trunk/lib/CodeGen/CGObjCGNU.cpp Sat Nov 19 02:17:24 2016
>>> @@ -18,6 +18,7 @@
>>>  #include "CGCleanup.h"
>>>  #include "CodeGenFunction.h"
>>>  #include "CodeGenModule.h"
>>> +#include "ConstantBuilder.h"
>>>  #include "clang/AST/ASTContext.h"
>>>  #include "clang/AST/Decl.h"
>>>  #include "clang/AST/DeclObjC.h"
>>> @@ -190,47 +191,17 @@ protected:
>>>    /// Generates a global structure, initialized by the elements in the
>>> vector.
>>>    /// The element types must match the types of the structure elements
>>> in the
>>>    /// first argument.
>>> -  llvm::GlobalVariable *MakeGlobal(llvm::StructType *Ty,
>>> -                                   ArrayRef<llvm::Constant *> V,
>>> +  llvm::GlobalVariable *MakeGlobal(llvm::Constant *C,
>>>                                     CharUnits Align,
>>>                                     StringRef Name="",
>>>                                     llvm::GlobalValue::LinkageTypes
>>> linkage
>>>                                           =llvm::GlobalValue::InternalLinkage)
>>> {
>>> -    llvm::Constant *C = llvm::ConstantStruct::get(Ty, V);
>>> -    auto GV = new llvm::GlobalVariable(TheModule, Ty, false,
>>> +    auto GV = new llvm::GlobalVariable(TheModule, C->getType(), false,
>>>                                         linkage, C, Name);
>>>      GV->setAlignment(Align.getQuantity());
>>>      return GV;
>>>    }
>>>
>>> -  /// Generates a global array.  The vector must contain the same
>>> number of
>>> -  /// elements that the array type declares, of the type specified as
>>> the array
>>> -  /// element type.
>>> -  llvm::GlobalVariable *MakeGlobal(llvm::ArrayType *Ty,
>>> -                                   ArrayRef<llvm::Constant *> V,
>>> -                                   CharUnits Align,
>>> -                                   StringRef Name="",
>>> -                                   llvm::GlobalValue::LinkageTypes
>>> linkage
>>> -                                         =llvm::GlobalValue::InternalLinkage)
>>> {
>>> -    llvm::Constant *C = llvm::ConstantArray::get(Ty, V);
>>> -    auto GV = new llvm::GlobalVariable(TheModule, Ty, false,
>>> -                                       linkage, C, Name);
>>> -    GV->setAlignment(Align.getQuantity());
>>> -    return GV;
>>> -  }
>>> -
>>> -  /// Generates a global array, inferring the array type from the
>>> specified
>>> -  /// element type and the size of the initialiser.
>>> -  llvm::GlobalVariable *MakeGlobalArray(llvm::Type *Ty,
>>> -                                        ArrayRef<llvm::Constant *> V,
>>> -                                        CharUnits Align,
>>> -                                        StringRef Name="",
>>> -                                        llvm::GlobalValue::LinkageTypes
>>> linkage
>>> -                                         =llvm::GlobalValue::InternalLinkage)
>>> {
>>> -    llvm::ArrayType *ArrayTy = llvm::ArrayType::get(Ty, V.size());
>>> -    return MakeGlobal(ArrayTy, V, Align, Name, linkage);
>>> -  }
>>> -
>>>    /// Returns a property name and encoding string.
>>>    llvm::Constant *MakePropertyEncodingString(const ObjCPropertyDecl
>>> *PD,
>>>                                               const Decl *Container) {
>>> @@ -251,7 +222,7 @@ protected:
>>>    }
>>>
>>>    /// Push the property attributes into two structure fields.
>>> -  void PushPropertyAttributes(std::vector<llvm::Constant*> &Fields,
>>> +  void PushPropertyAttributes(ConstantBuilder::StructBuilder &Fields,
>>>        ObjCPropertyDecl *property, bool isSynthesized=true, bool
>>>        isDynamic=true) {
>>>      int attrs = property->getPropertyAttributes();
>>> @@ -263,7 +234,7 @@ protected:
>>>        attrs &= ~ObjCPropertyDecl::OBJC_PR_strong;
>>>      }
>>>      // The first flags field has the same attribute values as clang
>>> uses internally
>>> -    Fields.push_back(llvm::ConstantInt::get(Int8Ty, attrs & 0xff));
>>> +    Fields.addInt(Int8Ty, attrs & 0xff);
>>>      attrs >>= 8;
>>>      attrs <<= 2;
>>>      // For protocol properties, synthesized and dynamic have no
>>> meaning, so we
>>> @@ -273,10 +244,10 @@ protected:
>>>      attrs |= isDynamic ? (1<<1) : 0;
>>>      // The second field is the next four fields left shifted by two,
>>> with the
>>>      // low bit set to indicate whether the field is synthesized or
>>> dynamic.
>>> -    Fields.push_back(llvm::ConstantInt::get(Int8Ty, attrs & 0xff));
>>> +    Fields.addInt(Int8Ty, attrs & 0xff);
>>>      // Two padding fields
>>> -    Fields.push_back(llvm::ConstantInt::get(Int8Ty, 0));
>>> -    Fields.push_back(llvm::ConstantInt::get(Int8Ty, 0));
>>> +    Fields.addInt(Int8Ty, 0);
>>> +    Fields.addInt(Int8Ty, 0);
>>>    }
>>>
>>>    /// Ensures that the value has the required type, by inserting a
>>> bitcast if
>>> @@ -1233,14 +1204,15 @@ llvm::Constant *CGObjCGNUstep::GetEHType
>>>    llvm::Constant *typeName =
>>>      ExportUniqueString(className, "__objc_eh_typename_");
>>>
>>> -  std::vector<llvm::Constant*> fields;
>>> -  fields.push_back(BVtable);
>>> -  fields.push_back(typeName);
>>> -  llvm::Constant *TI =
>>> -      MakeGlobal(llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty,
>>> nullptr),
>>> -                 fields, CGM.getPointerAlign(),
>>> -                 "__objc_eh_typeinfo_" + className,
>>> -          llvm::GlobalValue::LinkOnceODRLinkage);
>>> +  ConstantBuilder builder(CGM);
>>> +  auto fields = builder.beginStruct();
>>> +  fields.add(BVtable);
>>> +  fields.add(typeName);
>>> +  llvm::Constant *TI =
>>> +    fields.finishAndCreateGlobal("__objc_eh_typeinfo_" + className,
>>> +                                 CGM.getPointerAlign(),
>>> +                                 /*constant*/ false,
>>> +                                 llvm::GlobalValue::LinkOnceOD
>>> RLinkage);
>>>    return llvm::ConstantExpr::getBitCast(TI, PtrToInt8Ty);
>>>  }
>>>
>>> @@ -1270,13 +1242,13 @@ ConstantAddress CGObjCGNU::GenerateConst
>>>    else if (isa->getType() != PtrToIdTy)
>>>      isa = llvm::ConstantExpr::getBitCast(isa, PtrToIdTy);
>>>
>>> -  std::vector<llvm::Constant*> Ivars;
>>> -  Ivars.push_back(isa);
>>> -  Ivars.push_back(MakeConstantString(Str));
>>> -  Ivars.push_back(llvm::ConstantInt::get(IntTy, Str.size()));
>>> -  llvm::Constant *ObjCStr = MakeGlobal(
>>> -    llvm::StructType::get(PtrToIdTy, PtrToInt8Ty, IntTy, nullptr),
>>> -    Ivars, Align, ".objc_str");
>>> +  ConstantBuilder Builder(CGM);
>>> +  auto Fields = Builder.beginStruct();
>>> +  Fields.add(isa);
>>> +  Fields.add(MakeConstantString(Str));
>>> +  Fields.addInt(IntTy, Str.size());
>>> +  llvm::Constant *ObjCStr =
>>> +    Fields.finishAndCreateGlobal(".objc_str", Align);
>>>    ObjCStr = llvm::ConstantExpr::getBitCast(ObjCStr, PtrToInt8Ty);
>>>    ObjCStrings[Str] = ObjCStr;
>>>    ConstantStrings.push_back(ObjCStr);
>>> @@ -1551,13 +1523,20 @@ GenerateMethodList(StringRef ClassName,
>>>                     bool isClassMethodList) {
>>>    if (MethodSels.empty())
>>>      return NULLPtr;
>>> +
>>> +  ConstantBuilder Builder(CGM);
>>> +
>>> +  auto MethodList = Builder.beginStruct();
>>> +  MethodList.addNullPointer(CGM.Int8PtrTy);
>>> +  MethodList.addInt(Int32Ty, MethodTypes.size());
>>> +
>>>    // Get the method structure type.
>>>    llvm::StructType *ObjCMethodTy = llvm::StructType::get(
>>>      PtrToInt8Ty, // Really a selector, but the runtime creates it us.
>>>      PtrToInt8Ty, // Method types
>>>      IMPTy, //Method pointer
>>>      nullptr);
>>> -  std::vector<llvm::Constant*> Methods;
>>> +  auto Methods = MethodList.beginArray();
>>>    for (unsigned int i = 0, e = MethodTypes.size(); i < e; ++i) {
>>>      llvm::Constant *Method =
>>>        TheModule.getFunction(SymbolNameForMethod(ClassName,
>>> CategoryName,
>>> @@ -1567,34 +1546,14 @@ GenerateMethodList(StringRef ClassName,
>>>      llvm::Constant *C = MakeConstantString(MethodSels[
>>> i].getAsString());
>>>      Method = llvm::ConstantExpr::getBitCast(Method,
>>>          IMPTy);
>>> -    Methods.push_back(
>>> +    Methods.add(
>>>          llvm::ConstantStruct::get(ObjCMethodTy, {C, MethodTypes[i],
>>> Method}));
>>>    }
>>> -
>>> -  // Array of method structures
>>> -  llvm::ArrayType *ObjCMethodArrayTy = llvm::ArrayType::get(ObjCMetho
>>> dTy,
>>> -
>>> Methods.size());
>>> -  llvm::Constant *MethodArray = llvm::ConstantArray::get(ObjCM
>>> ethodArrayTy,
>>> -                                                         Methods);
>>> -
>>> -  // Structure containing list pointer, array and array count
>>> -  llvm::StructType *ObjCMethodListTy = llvm::StructType::create(VMCon
>>> text);
>>> -  llvm::Type *NextPtrTy = llvm::PointerType::getUnqual(O
>>> bjCMethodListTy);
>>> -  ObjCMethodListTy->setBody(
>>> -      NextPtrTy,
>>> -      IntTy,
>>> -      ObjCMethodArrayTy,
>>> -      nullptr);
>>> -
>>> -  Methods.clear();
>>> -  Methods.push_back(llvm::ConstantPointerNull::get(
>>> -        llvm::PointerType::getUnqual(ObjCMethodListTy)));
>>> -  Methods.push_back(llvm::ConstantInt::get(Int32Ty,
>>> MethodTypes.size()));
>>> -  Methods.push_back(MethodArray);
>>> +  MethodList.add(Methods.finish());
>>>
>>>    // Create an instance of the structure
>>> -  return MakeGlobal(ObjCMethodListTy, Methods, CGM.getPointerAlign(),
>>> -                    ".objc_method_list");
>>> +  return MethodList.finishAndCreateGlobal(".objc_method_list",
>>> +                                          CGM.getPointerAlign());
>>>  }
>>>
>>>  /// Generates an IvarList.  Used in construction of a objc_class.
>>> @@ -1602,35 +1561,36 @@ llvm::Constant *CGObjCGNU::
>>>  GenerateIvarList(ArrayRef<llvm::Constant *> IvarNames,
>>>                   ArrayRef<llvm::Constant *> IvarTypes,
>>>                   ArrayRef<llvm::Constant *> IvarOffsets) {
>>> -  if (IvarNames.size() == 0)
>>> +  if (IvarNames.empty())
>>>      return NULLPtr;
>>> -  // Get the method structure type.
>>> +
>>> +  ConstantBuilder Builder(CGM);
>>> +
>>> +  // Structure containing array count followed by array.
>>> +  auto IvarList = Builder.beginStruct();
>>> +  IvarList.addInt(IntTy, (int)IvarNames.size());
>>> +
>>> +  // Get the ivar structure type.
>>>    llvm::StructType *ObjCIvarTy = llvm::StructType::get(
>>>      PtrToInt8Ty,
>>>      PtrToInt8Ty,
>>>      IntTy,
>>>      nullptr);
>>> -  std::vector<llvm::Constant*> Ivars;
>>> +
>>> +  // Array of ivar structures.
>>> +  auto Ivars = IvarList.beginArray(ObjCIvarTy);
>>>    for (unsigned int i = 0, e = IvarNames.size() ; i < e ; i++) {
>>> -    Ivars.push_back(llvm::ConstantStruct::get(
>>> -        ObjCIvarTy, {IvarNames[i], IvarTypes[i], IvarOffsets[i]}));
>>> +    auto Ivar = Ivars.beginStruct(ObjCIvarTy);
>>> +    Ivar.add(IvarNames[i]);
>>> +    Ivar.add(IvarTypes[i]);
>>> +    Ivar.add(IvarOffsets[i]);
>>> +    Ivars.add(Ivar.finish());
>>>    }
>>> -
>>> -  // Array of method structures
>>> -  llvm::ArrayType *ObjCIvarArrayTy = llvm::ArrayType::get(ObjCIvarTy,
>>> -      IvarNames.size());
>>> -
>>> -  llvm::Constant *Elements[] = {
>>> -      llvm::ConstantInt::get(IntTy, (int)IvarNames.size()),
>>> -      llvm::ConstantArray::get(ObjCIvarArrayTy, Ivars)};
>>> -  // Structure containing array and array count
>>> -  llvm::StructType *ObjCIvarListTy = llvm::StructType::get(IntTy,
>>> -    ObjCIvarArrayTy,
>>> -    nullptr);
>>> +  IvarList.add(Ivars.finish());
>>>
>>>    // Create an instance of the structure
>>> -  return MakeGlobal(ObjCIvarListTy, Elements, CGM.getPointerAlign(),
>>> -                    ".objc_ivar_list");
>>> +  return IvarList.finishAndCreateGlobal(".objc_ivar_list",
>>> +                                        CGM.getPointerAlign());
>>>  }
>>>
>>>  /// Generate a class structure
>>> @@ -1678,34 +1638,55 @@ llvm::Constant *CGObjCGNU::GenerateClass
>>>        IntPtrTy,               // strong_pointers
>>>        IntPtrTy,               // weak_pointers
>>>        nullptr);
>>> -  llvm::Constant *Zero = llvm::ConstantInt::get(LongTy, 0);
>>> +
>>> +  ConstantBuilder Builder(CGM);
>>> +  auto Elements = Builder.beginStruct(ClassTy);
>>> +
>>>    // Fill in the structure
>>> -  std::vector<llvm::Constant*> Elements;
>>> -  Elements.push_back(llvm::ConstantExpr::getBitCast(MetaClass,
>>> PtrToInt8Ty));
>>> -  Elements.push_back(SuperClass);
>>> -  Elements.push_back(MakeConstantString(Name, ".class_name"));
>>> -  Elements.push_back(Zero);
>>> -  Elements.push_back(llvm::ConstantInt::get(LongTy, info));
>>> +
>>> +  // isa
>>> +  Elements.add(llvm::ConstantExpr::getBitCast(MetaClass, PtrToInt8Ty));
>>> +  // super_class
>>> +  Elements.add(SuperClass);
>>> +  // name
>>> +  Elements.add(MakeConstantString(Name, ".class_name"));
>>> +  // version
>>> +  Elements.addInt(LongTy, 0);
>>> +  // info
>>> +  Elements.addInt(LongTy, info);
>>> +  // instance_size
>>>    if (isMeta) {
>>>      llvm::DataLayout td(&TheModule);
>>> -    Elements.push_back(
>>> -        llvm::ConstantInt::get(LongTy,
>>> -                               td.getTypeSizeInBits(ClassTy) /
>>> -                                 CGM.getContext().getCharWidth()));
>>> +    Elements.addInt(LongTy,
>>> +                    td.getTypeSizeInBits(ClassTy) /
>>> +                      CGM.getContext().getCharWidth());
>>>    } else
>>> -    Elements.push_back(InstanceSize);
>>> -  Elements.push_back(IVars);
>>> -  Elements.push_back(Methods);
>>> -  Elements.push_back(NULLPtr);
>>> -  Elements.push_back(NULLPtr);
>>> -  Elements.push_back(NULLPtr);
>>> -  Elements.push_back(llvm::ConstantExpr::getBitCast(Protocols, PtrTy));
>>> -  Elements.push_back(NULLPtr);
>>> -  Elements.push_back(llvm::ConstantInt::get(LongTy, 1));
>>> -  Elements.push_back(IvarOffsets);
>>> -  Elements.push_back(Properties);
>>> -  Elements.push_back(StrongIvarBitmap);
>>> -  Elements.push_back(WeakIvarBitmap);
>>> +    Elements.add(InstanceSize);
>>> +  // ivars
>>> +  Elements.add(IVars);
>>> +  // methods
>>> +  Elements.add(Methods);
>>> +  // These are all filled in by the runtime, so we pretend
>>> +  // dtable
>>> +  Elements.add(NULLPtr);
>>> +  // subclass_list
>>> +  Elements.add(NULLPtr);
>>> +  // sibling_class
>>> +  Elements.add(NULLPtr);
>>> +  // protocols
>>> +  Elements.add(llvm::ConstantExpr::getBitCast(Protocols, PtrTy));
>>> +  // gc_object_type
>>> +  Elements.add(NULLPtr);
>>> +  // abi_version
>>> +  Elements.addInt(LongTy, 1);
>>> +  // ivar_offsets
>>> +  Elements.add(IvarOffsets);
>>> +  // properties
>>> +  Elements.add(Properties);
>>> +  // strong_pointers
>>> +  Elements.add(StrongIvarBitmap);
>>> +  // weak_pointers
>>> +  Elements.add(WeakIvarBitmap);
>>>    // Create an instance of the structure
>>>    // This is now an externally visible symbol, so that we can speed up
>>> class
>>>    // messages in the next ABI.  We may already have some weak
>>> references to
>>> @@ -1714,13 +1695,13 @@ llvm::Constant *CGObjCGNU::GenerateClass
>>>            std::string(Name));
>>>    llvm::GlobalVariable *ClassRef = TheModule.getNamedGlobal(ClassSym);
>>>    llvm::Constant *Class =
>>> -    MakeGlobal(ClassTy, Elements, CGM.getPointerAlign(), ClassSym,
>>> -               llvm::GlobalValue::ExternalLinkage);
>>> +    Elements.finishAndCreateGlobal(ClassSym, CGM.getPointerAlign(),
>>> false,
>>> +                                   llvm::GlobalValue::ExternalLinkage);
>>>    if (ClassRef) {
>>> -      ClassRef->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(
>>> Class,
>>> +    ClassRef->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(Class,
>>>                    ClassRef->getType()));
>>> -      ClassRef->removeFromParent();
>>> -      Class->setName(ClassSym);
>>> +    ClassRef->removeFromParent();
>>> +    Class->setName(ClassSym);
>>>    }
>>>    return Class;
>>>  }
>>> @@ -1729,38 +1710,33 @@ llvm::Constant *CGObjCGNU::
>>>  GenerateProtocolMethodList(ArrayRef<llvm::Constant *> MethodNames,
>>>                             ArrayRef<llvm::Constant *> MethodTypes) {
>>>    // Get the method structure type.
>>> -  llvm::StructType *ObjCMethodDescTy = llvm::StructType::get(
>>> -    PtrToInt8Ty, // Really a selector, but the runtime does the casting
>>> for us.
>>> -    PtrToInt8Ty,
>>> -    nullptr);
>>> -  std::vector<llvm::Constant*> Methods;
>>> +  llvm::StructType *ObjCMethodDescTy =
>>> +    llvm::StructType::get(CGM.getLLVMContext(), { PtrToInt8Ty,
>>> PtrToInt8Ty });
>>> +  ConstantBuilder Builder(CGM);
>>> +  auto MethodList = Builder.beginStruct();
>>> +  MethodList.addInt(IntTy, MethodNames.size());
>>> +  auto Methods = MethodList.beginArray(ObjCMethodDescTy);
>>>    for (unsigned int i = 0, e = MethodTypes.size() ; i < e ; i++) {
>>> -    Methods.push_back(llvm::ConstantStruct::get(
>>> -        ObjCMethodDescTy, {MethodNames[i], MethodTypes[i]}));
>>> -  }
>>> -  llvm::ArrayType *ObjCMethodArrayTy = llvm::ArrayType::get(ObjCMetho
>>> dDescTy,
>>> -      MethodNames.size());
>>> -  llvm::Constant *Array = llvm::ConstantArray::get(ObjCMethodArrayTy,
>>> -                                                   Methods);
>>> -  llvm::StructType *ObjCMethodDescListTy = llvm::StructType::get(
>>> -      IntTy, ObjCMethodArrayTy, nullptr);
>>> -  Methods.clear();
>>> -  Methods.push_back(llvm::ConstantInt::get(IntTy, MethodNames.size()));
>>> -  Methods.push_back(Array);
>>> -  return MakeGlobal(ObjCMethodDescListTy, Methods,
>>> CGM.getPointerAlign(),
>>> -                    ".objc_method_list");
>>> +    auto Method = Methods.beginStruct(ObjCMethodDescTy);
>>> +    Method.add(MethodNames[i]);
>>> +    Method.add(MethodTypes[i]);
>>> +    Methods.add(Method.finish());
>>> +  }
>>> +  MethodList.add(Methods.finish());
>>> +  return MethodList.finishAndCreateGlobal(".objc_method_list",
>>> +                                          CGM.getPointerAlign());
>>>  }
>>>
>>>  // Create the protocol list structure used in classes, categories and
>>> so on
>>> -llvm::Constant *CGObjCGNU::GenerateProtocolLi
>>> st(ArrayRef<std::string>Protocols){
>>> -  llvm::ArrayType *ProtocolArrayTy = llvm::ArrayType::get(PtrToInt8Ty,
>>> -      Protocols.size());
>>> -  llvm::StructType *ProtocolListTy = llvm::StructType::get(
>>> -      PtrTy, //Should be a recurisve pointer, but it's always NULL here.
>>> -      SizeTy,
>>> -      ProtocolArrayTy,
>>> -      nullptr);
>>> -  std::vector<llvm::Constant*> Elements;
>>> +llvm::Constant *
>>> +CGObjCGNU::GenerateProtocolList(ArrayRef<std::string> Protocols) {
>>> +
>>> +  ConstantBuilder Builder(CGM);
>>> +  auto ProtocolList = Builder.beginStruct();
>>> +  ProtocolList.add(NULLPtr);
>>> +  ProtocolList.addInt(LongTy, Protocols.size());
>>> +
>>> +  auto Elements = ProtocolList.beginArray(PtrToInt8Ty);
>>>    for (const std::string *iter = Protocols.begin(), *endIter =
>>> Protocols.end();
>>>        iter != endIter ; iter++) {
>>>      llvm::Constant *protocol = nullptr;
>>> @@ -1773,16 +1749,11 @@ llvm::Constant *CGObjCGNU::GenerateProto
>>>      }
>>>      llvm::Constant *Ptr = llvm::ConstantExpr::getBitCast(protocol,
>>>                                                             PtrToInt8Ty);
>>> -    Elements.push_back(Ptr);
>>> +    Elements.add(Ptr);
>>>    }
>>> -  llvm::Constant * ProtocolArray = llvm::ConstantArray::get(Proto
>>> colArrayTy,
>>> -      Elements);
>>> -  Elements.clear();
>>> -  Elements.push_back(NULLPtr);
>>> -  Elements.push_back(llvm::ConstantInt::get(LongTy, Protocols.size()));
>>> -  Elements.push_back(ProtocolArray);
>>> -  return MakeGlobal(ProtocolListTy, Elements, CGM.getPointerAlign(),
>>> -                    ".objc_protocol_list");
>>> +  ProtocolList.add(Elements.finish());
>>> +  return ProtocolList.finishAndCreateGlobal(".objc_protocol_list",
>>> +                                            CGM.getPointerAlign());
>>>  }
>>>
>>>  llvm::Value *CGObjCGNU::GenerateProtocolRef(CodeGenFunction &CGF,
>>> @@ -1793,33 +1764,28 @@ llvm::Value *CGObjCGNU::GenerateProtocol
>>>    return CGF.Builder.CreateBitCast(protocol,
>>> llvm::PointerType::getUnqual(T));
>>>  }
>>>
>>> -llvm::Constant *CGObjCGNU::GenerateEmptyProtocol(
>>> -  const std::string &ProtocolName) {
>>> -  SmallVector<std::string, 0> EmptyStringVector;
>>> -  SmallVector<llvm::Constant*, 0> EmptyConstantVector;
>>> -
>>> -  llvm::Constant *ProtocolList = GenerateProtocolList(EmptyStri
>>> ngVector);
>>> -  llvm::Constant *MethodList =
>>> -    GenerateProtocolMethodList(EmptyConstantVector,
>>> EmptyConstantVector);
>>> +llvm::Constant *
>>> +CGObjCGNU::GenerateEmptyProtocol(const std::string &ProtocolName) {
>>> +  llvm::Constant *ProtocolList = GenerateProtocolList({});
>>> +  llvm::Constant *MethodList = GenerateProtocolMethodList({}, {});
>>>    // Protocols are objects containing lists of the methods implemented
>>> and
>>>    // protocols adopted.
>>> -  llvm::StructType *ProtocolTy = llvm::StructType::get(IdTy,
>>> -      PtrToInt8Ty,
>>> -      ProtocolList->getType(),
>>> -      MethodList->getType(),
>>> -      MethodList->getType(),
>>> -      MethodList->getType(),
>>> -      MethodList->getType(),
>>> -      nullptr);
>>> +  ConstantBuilder Builder(CGM);
>>> +  auto Elements = Builder.beginStruct();
>>> +
>>>    // The isa pointer must be set to a magic number so the runtime knows
>>> it's
>>>    // the correct layout.
>>> -  llvm::Constant *Elements[] = {
>>> -      llvm::ConstantExpr::getIntToPtr(
>>> -          llvm::ConstantInt::get(Int32Ty, ProtocolVersion), IdTy),
>>> -      MakeConstantString(ProtocolName, ".objc_protocol_name"),
>>> ProtocolList,
>>> -      MethodList, MethodList, MethodList, MethodList};
>>> -  return MakeGlobal(ProtocolTy, Elements, CGM.getPointerAlign(),
>>> -                    ".objc_protocol");
>>> +  Elements.add(llvm::ConstantExpr::getIntToPtr(
>>> +          llvm::ConstantInt::get(Int32Ty, ProtocolVersion), IdTy));
>>> +
>>> +  Elements.add(MakeConstantString(ProtocolName,
>>> ".objc_protocol_name"));
>>> +  Elements.add(ProtocolList);
>>> +  Elements.add(MethodList);
>>> +  Elements.add(MethodList);
>>> +  Elements.add(MethodList);
>>> +  Elements.add(MethodList);
>>> +  return Elements.finishAndCreateGlobal(".objc_protocol",
>>> +                                        CGM.getPointerAlign());
>>>  }
>>>
>>>  void CGObjCGNU::GenerateProtocol(const ObjCProtocolDecl *PD) {
>>> @@ -1886,142 +1852,143 @@ void CGObjCGNU::GenerateProtocol(const O
>>>    // The isSynthesized value is always set to 0 in a protocol.  It
>>> exists to
>>>    // simplify the runtime library by allowing it to use the same data
>>>    // structures for protocol metadata everywhere.
>>> -  llvm::StructType *PropertyMetadataTy = llvm::StructType::get(
>>> -          PtrToInt8Ty, Int8Ty, Int8Ty, Int8Ty, Int8Ty, PtrToInt8Ty,
>>> -          PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty, nullptr);
>>> -  std::vector<llvm::Constant*> Properties;
>>> -  std::vector<llvm::Constant*> OptionalProperties;
>>>
>>> -  // Add all of the property methods need adding to the method list and
>>> to the
>>> -  // property metadata list.
>>> -  for (auto *property : PD->instance_properties()) {
>>> -    std::vector<llvm::Constant*> Fields;
>>> -
>>> -    Fields.push_back(MakePropertyEncodingString(property, nullptr));
>>> -    PushPropertyAttributes(Fields, property);
>>> +  llvm::Constant *PropertyList;
>>> +  llvm::Constant *OptionalPropertyList;
>>> +  {
>>> +    llvm::StructType *propertyMetadataTy =
>>> +      llvm::StructType::get(CGM.getLLVMContext(),
>>> +        { PtrToInt8Ty, Int8Ty, Int8Ty, Int8Ty, Int8Ty, PtrToInt8Ty,
>>> +          PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty });
>>> +
>>> +    unsigned numReqProperties = 0, numOptProperties = 0;
>>> +    for (auto property : PD->instance_properties()) {
>>> +      if (property->isOptional())
>>> +        numOptProperties++;
>>> +      else
>>> +        numReqProperties++;
>>> +    }
>>> +
>>> +    ConstantBuilder reqPropertyListBuilder(CGM);
>>> +    auto reqPropertiesList = reqPropertyListBuilder.beginStruct();
>>> +    reqPropertiesList.addInt(IntTy, numReqProperties);
>>> +    reqPropertiesList.add(NULLPtr);
>>> +    auto reqPropertiesArray = reqPropertiesList.beginArray(p
>>> ropertyMetadataTy);
>>> +
>>> +    ConstantBuilder optPropertyListBuilder(CGM);
>>> +    auto optPropertiesList = optPropertyListBuilder.beginStruct();
>>> +    optPropertiesList.addInt(IntTy, numOptProperties);
>>> +    optPropertiesList.add(NULLPtr);
>>> +    auto optPropertiesArray = optPropertiesList.beginArray(p
>>> ropertyMetadataTy);
>>> +
>>> +    // Add all of the property methods need adding to the method list
>>> and to the
>>> +    // property metadata list.
>>> +    for (auto *property : PD->instance_properties()) {
>>> +      auto &propertiesArray =
>>> +        (property->isOptional() ? optPropertiesArray :
>>> reqPropertiesArray);
>>> +      auto fields = propertiesArray.beginStruct(propertyMetadataTy);
>>> +
>>> +      fields.add(MakePropertyEncodingString(property, nullptr));
>>> +      PushPropertyAttributes(fields, property);
>>> +
>>> +      if (ObjCMethodDecl *getter = property->getGetterMethodDecl()) {
>>> +        std::string typeStr;
>>> +        Context.getObjCEncodingForMethodDecl(getter, typeStr);
>>> +        llvm::Constant *typeEncoding = MakeConstantString(typeStr);
>>> +        InstanceMethodTypes.push_back(typeEncoding);
>>> +        fields.add(MakeConstantString(getter->getSelector().getAsStr
>>> ing()));
>>> +        fields.add(typeEncoding);
>>> +      } else {
>>> +        fields.add(NULLPtr);
>>> +        fields.add(NULLPtr);
>>> +      }
>>> +      if (ObjCMethodDecl *setter = property->getSetterMethodDecl()) {
>>> +        std::string typeStr;
>>> +        Context.getObjCEncodingForMethodDecl(setter, typeStr);
>>> +        llvm::Constant *typeEncoding = MakeConstantString(typeStr);
>>> +        InstanceMethodTypes.push_back(typeEncoding);
>>> +        fields.add(MakeConstantString(setter->getSelector().getAsStr
>>> ing()));
>>> +        fields.add(typeEncoding);
>>> +      } else {
>>> +        fields.add(NULLPtr);
>>> +        fields.add(NULLPtr);
>>> +      }
>>>
>>> -    if (ObjCMethodDecl *getter = property->getGetterMethodDecl()) {
>>> -      std::string TypeStr;
>>> -      Context.getObjCEncodingForMethodDecl(getter,TypeStr);
>>> -      llvm::Constant *TypeEncoding = MakeConstantString(TypeStr);
>>> -      InstanceMethodTypes.push_back(TypeEncoding);
>>> -      Fields.push_back(MakeConstantString(getter->getSelector().ge
>>> tAsString()));
>>> -      Fields.push_back(TypeEncoding);
>>> -    } else {
>>> -      Fields.push_back(NULLPtr);
>>> -      Fields.push_back(NULLPtr);
>>> -    }
>>> -    if (ObjCMethodDecl *setter = property->getSetterMethodDecl()) {
>>> -      std::string TypeStr;
>>> -      Context.getObjCEncodingForMethodDecl(setter,TypeStr);
>>> -      llvm::Constant *TypeEncoding = MakeConstantString(TypeStr);
>>> -      InstanceMethodTypes.push_back(TypeEncoding);
>>> -      Fields.push_back(MakeConstantString(setter->getSelector().ge
>>> tAsString()));
>>> -      Fields.push_back(TypeEncoding);
>>> -    } else {
>>> -      Fields.push_back(NULLPtr);
>>> -      Fields.push_back(NULLPtr);
>>> -    }
>>> -    if (property->getPropertyImplementation() ==
>>> ObjCPropertyDecl::Optional) {
>>> -      OptionalProperties.push_back(llvm::ConstantStruct::get(PropertyMetadataTy,
>>> Fields));
>>> -    } else {
>>> -      Properties.push_back(llvm::ConstantStruct::get(PropertyMetadataTy,
>>> Fields));
>>> +      propertiesArray.add(fields.finish());
>>>      }
>>> +
>>> +    reqPropertiesList.add(reqPropertiesArray.finish());
>>> +    PropertyList =
>>> +      reqPropertiesList.finishAndCreateGlobal(".objc_property_list",
>>> +                                              CGM.getPointerAlign());
>>> +
>>> +    optPropertiesList.add(optPropertiesArray.finish());
>>> +    OptionalPropertyList =
>>> +      optPropertiesList.finishAndCreateGlobal(".objc_property_list",
>>> +                                              CGM.getPointerAlign());
>>>    }
>>> -  llvm::Constant *PropertyArray = llvm::ConstantArray::get(
>>> -      llvm::ArrayType::get(PropertyMetadataTy, Properties.size()),
>>> Properties);
>>> -  llvm::Constant* PropertyListInitFields[] =
>>> -    {llvm::ConstantInt::get(IntTy, Properties.size()), NULLPtr,
>>> PropertyArray};
>>> -
>>> -  llvm::Constant *PropertyListInit =
>>> -      llvm::ConstantStruct::getAnon(PropertyListInitFields);
>>> -  llvm::Constant *PropertyList = new llvm::GlobalVariable(TheModule,
>>> -      PropertyListInit->getType(), false, llvm::GlobalValue::InternalLin
>>> kage,
>>> -      PropertyListInit, ".objc_property_list");
>>> -
>>> -  llvm::Constant *OptionalPropertyArray =
>>> -      llvm::ConstantArray::get(llvm::ArrayType::get(PropertyMetadataTy,
>>> -          OptionalProperties.size()) , OptionalProperties);
>>> -  llvm::Constant* OptionalPropertyListInitFields[] = {
>>> -      llvm::ConstantInt::get(IntTy, OptionalProperties.size()), NULLPtr,
>>> -      OptionalPropertyArray };
>>> -
>>> -  llvm::Constant *OptionalPropertyListInit =
>>> -      llvm::ConstantStruct::getAnon(OptionalPropertyListInitFields);
>>> -  llvm::Constant *OptionalPropertyList = new
>>> llvm::GlobalVariable(TheModule,
>>> -          OptionalPropertyListInit->getType(), false,
>>> -          llvm::GlobalValue::InternalLinkage, OptionalPropertyListInit,
>>> -          ".objc_property_list");
>>>
>>>    // Protocols are objects containing lists of the methods implemented
>>> and
>>>    // protocols adopted.
>>> -  llvm::StructType *ProtocolTy = llvm::StructType::get(IdTy,
>>> -      PtrToInt8Ty,
>>> -      ProtocolList->getType(),
>>> -      InstanceMethodList->getType(),
>>> -      ClassMethodList->getType(),
>>> -      OptionalInstanceMethodList->getType(),
>>> -      OptionalClassMethodList->getType(),
>>> -      PropertyList->getType(),
>>> -      OptionalPropertyList->getType(),
>>> -      nullptr);
>>>    // The isa pointer must be set to a magic number so the runtime knows
>>> it's
>>>    // the correct layout.
>>> -  llvm::Constant *Elements[] = {
>>> +  ConstantBuilder Builder(CGM);
>>> +  auto Elements = Builder.beginStruct();
>>> +  Elements.add(
>>>        llvm::ConstantExpr::getIntToPtr(
>>> -          llvm::ConstantInt::get(Int32Ty, ProtocolVersion), IdTy),
>>> -      MakeConstantString(ProtocolName, ".objc_protocol_name"),
>>> ProtocolList,
>>> -      InstanceMethodList, ClassMethodList, OptionalInstanceMethodList,
>>> -      OptionalClassMethodList, PropertyList, OptionalPropertyList};
>>> +          llvm::ConstantInt::get(Int32Ty, ProtocolVersion), IdTy));
>>> +  Elements.add(
>>> +      MakeConstantString(ProtocolName, ".objc_protocol_name"));
>>> +  Elements.add(ProtocolList);
>>> +  Elements.add(InstanceMethodList);
>>> +  Elements.add(ClassMethodList);
>>> +  Elements.add(OptionalInstanceMethodList);
>>> +  Elements.add(OptionalClassMethodList);
>>> +  Elements.add(PropertyList);
>>> +  Elements.add(OptionalPropertyList);
>>>    ExistingProtocols[ProtocolName] =
>>> -    llvm::ConstantExpr::getBitCast(MakeGlobal(ProtocolTy, Elements,
>>> -          CGM.getPointerAlign(), ".objc_protocol"), IdTy);
>>> +    llvm::ConstantExpr::getBitCast(
>>> +      Elements.finishAndCreateGlobal(".objc_protocol",
>>> CGM.getPointerAlign()),
>>> +      IdTy);
>>>  }
>>>  void CGObjCGNU::GenerateProtocolHolderCategory() {
>>>    // Collect information about instance methods
>>>    SmallVector<Selector, 1> MethodSels;
>>>    SmallVector<llvm::Constant*, 1> MethodTypes;
>>>
>>> -  std::vector<llvm::Constant*> Elements;
>>> +  ConstantBuilder Builder(CGM);
>>> +  auto Elements = Builder.beginStruct();
>>> +
>>>    const std::string ClassName = "__ObjC_Protocol_Holder_Ugly_Hack";
>>>    const std::string CategoryName = "AnotherHack";
>>> -  Elements.push_back(MakeConstantString(CategoryName));
>>> -  Elements.push_back(MakeConstantString(ClassName));
>>> +  Elements.add(MakeConstantString(CategoryName));
>>> +  Elements.add(MakeConstantString(ClassName));
>>>    // Instance method list
>>> -  Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList(
>>> +  Elements.add(llvm::ConstantExpr::getBitCast(GenerateMethodList(
>>>            ClassName, CategoryName, MethodSels, MethodTypes, false),
>>> PtrTy));
>>>    // Class method list
>>> -  Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList(
>>> +  Elements.add(llvm::ConstantExpr::getBitCast(GenerateMethodList(
>>>            ClassName, CategoryName, MethodSels, MethodTypes, true),
>>> PtrTy));
>>> +
>>>    // Protocol list
>>> -  llvm::ArrayType *ProtocolArrayTy = llvm::ArrayType::get(PtrTy,
>>> -      ExistingProtocols.size());
>>> -  llvm::StructType *ProtocolListTy = llvm::StructType::get(
>>> -      PtrTy, //Should be a recurisve pointer, but it's always NULL here.
>>> -      SizeTy,
>>> -      ProtocolArrayTy,
>>> -      nullptr);
>>> -  std::vector<llvm::Constant*> ProtocolElements;
>>> -  for (llvm::StringMapIterator<llvm::Constant*> iter =
>>> -       ExistingProtocols.begin(), endIter = ExistingProtocols.end();
>>> +  ConstantBuilder ProtocolListBuilder(CGM);
>>> +  auto ProtocolList = ProtocolListBuilder.beginStruct();
>>> +  ProtocolList.add(NULLPtr);
>>> +  ProtocolList.addInt(LongTy, ExistingProtocols.size());
>>> +  auto ProtocolElements = ProtocolList.beginArray(PtrTy);
>>> +  for (auto iter = ExistingProtocols.begin(), endIter =
>>> ExistingProtocols.end();
>>>         iter != endIter ; iter++) {
>>>      llvm::Constant *Ptr = llvm::ConstantExpr::getBitCast
>>> (iter->getValue(),
>>>              PtrTy);
>>> -    ProtocolElements.push_back(Ptr);
>>> +    ProtocolElements.add(Ptr);
>>>    }
>>> -  llvm::Constant * ProtocolArray = llvm::ConstantArray::get(Proto
>>> colArrayTy,
>>> -      ProtocolElements);
>>> -  ProtocolElements.clear();
>>> -  ProtocolElements.push_back(NULLPtr);
>>> -  ProtocolElements.push_back(llvm::ConstantInt::get(LongTy,
>>> -              ExistingProtocols.size()));
>>> -  ProtocolElements.push_back(ProtocolArray);
>>> -  Elements.push_back(llvm::ConstantExpr::getBitCast(MakeGlobal
>>> (ProtocolListTy,
>>> -                  ProtocolElements, CGM.getPointerAlign(),
>>> -                  ".objc_protocol_list"), PtrTy));
>>> +  ProtocolList.add(ProtocolElements.finish());
>>> +  Elements.add(llvm::ConstantExpr::getBitCast(
>>> +                   ProtocolList.finishAndCreateG
>>> lobal(".objc_protocol_list",
>>> +
>>> CGM.getPointerAlign()),
>>> +                   PtrTy));
>>>    Categories.push_back(llvm::ConstantExpr::getBitCast(
>>> -        MakeGlobal(llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty,
>>> -            PtrTy, PtrTy, PtrTy, nullptr), Elements,
>>> CGM.getPointerAlign()),
>>> +        Elements.finishAndCreateGlobal("", CGM.getPointerAlign()),
>>>          PtrTy));
>>>  }
>>>
>>> @@ -2056,13 +2023,16 @@ llvm::Constant *CGObjCGNU::MakeBitField(
>>>      }
>>>      values.push_back(llvm::ConstantInt::get(Int32Ty, word));
>>>    }
>>> -  llvm::ArrayType *arrayTy = llvm::ArrayType::get(Int32Ty,
>>> values.size());
>>> -  llvm::Constant *array = llvm::ConstantArray::get(arrayTy, values);
>>> -  llvm::Constant *fields[2] = {
>>> -      llvm::ConstantInt::get(Int32Ty, values.size()),
>>> -      array };
>>> -  llvm::Constant *GS = MakeGlobal(llvm::StructType::get(Int32Ty,
>>> arrayTy,
>>> -        nullptr), fields, CharUnits::fromQuantity(4));
>>> +
>>> +  ConstantBuilder builder(CGM);
>>> +  auto fields = builder.beginStruct();
>>> +  fields.addInt(Int32Ty, values.size());
>>> +  auto array = fields.beginArray();
>>> +  for (auto v : values) array.add(v);
>>> +  fields.add(array.finish());
>>> +
>>> +  llvm::Constant *GS =
>>> +    fields.finishAndCreateGlobal("", CharUnits::fromQuantity(4));
>>>    llvm::Constant *ptr = llvm::ConstantExpr::getPtrToInt(GS, IntPtrTy);
>>>    return ptr;
>>>  }
>>> @@ -2098,23 +2068,25 @@ void CGObjCGNU::GenerateCategory(const O
>>>         E = Protos.end(); I != E; ++I)
>>>      Protocols.push_back((*I)->getNameAsString());
>>>
>>> -  llvm::Constant *Elements[] = {
>>> -      MakeConstantString(CategoryName), MakeConstantString(ClassName),
>>> -      // Instance method list
>>> -      llvm::ConstantExpr::getBitCast(
>>> +  ConstantBuilder Builder(CGM);
>>> +  auto Elements = Builder.beginStruct();
>>> +  Elements.add(MakeConstantString(CategoryName));
>>> +  Elements.add(MakeConstantString(ClassName));
>>> +  // Instance method list
>>> +  Elements.add(llvm::ConstantExpr::getBitCast(
>>>            GenerateMethodList(ClassName, CategoryName,
>>> InstanceMethodSels,
>>>                               InstanceMethodTypes, false),
>>> -          PtrTy),
>>> -      // Class method list
>>> -      llvm::ConstantExpr::getBitCast(GenerateMethodList(ClassName,
>>> CategoryName,
>>> -                                                        ClassMethodSels,
>>> -
>>> ClassMethodTypes, true),
>>> -                                     PtrTy),
>>> -      // Protocol list
>>> -      llvm::ConstantExpr::getBitCast(GenerateProtocolList(Protocols),
>>> PtrTy)};
>>> +          PtrTy));
>>> +  // Class method list
>>> +  Elements.add(llvm::ConstantExpr::getBitCast(
>>> +                 GenerateMethodList(ClassName, CategoryName,
>>> +                                    ClassMethodSels, ClassMethodTypes,
>>> true),
>>> +                  PtrTy));
>>> +  // Protocol list
>>> +  Elements.add(llvm::ConstantExpr::getBitCast(
>>> +                 GenerateProtocolList(Protocols), PtrTy));
>>>    Categories.push_back(llvm::ConstantExpr::getBitCast(
>>> -        MakeGlobal(llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty,
>>> -            PtrTy, PtrTy, PtrTy, nullptr), Elements,
>>> CGM.getPointerAlign()),
>>> +        Elements.finishAndCreateGlobal("", CGM.getPointerAlign()),
>>>          PtrTy));
>>>  }
>>>
>>> @@ -2124,23 +2096,35 @@ llvm::Constant *CGObjCGNU::GeneratePrope
>>>    ASTContext &Context = CGM.getContext();
>>>    // Property metadata: name, attributes, attributes2, padding1,
>>> padding2,
>>>    // setter name, setter types, getter name, getter types.
>>> -  llvm::StructType *PropertyMetadataTy = llvm::StructType::get(
>>> -          PtrToInt8Ty, Int8Ty, Int8Ty, Int8Ty, Int8Ty, PtrToInt8Ty,
>>> -          PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty, nullptr);
>>> -  std::vector<llvm::Constant*> Properties;
>>> +  llvm::StructType *propertyMetadataTy =
>>> +    llvm::StructType::get(CGM.getLLVMContext(),
>>> +        { PtrToInt8Ty, Int8Ty, Int8Ty, Int8Ty, Int8Ty, PtrToInt8Ty,
>>> +          PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty });
>>> +
>>> +  unsigned numProperties = 0;
>>> +  for (auto *propertyImpl : OID->property_impls()) {
>>> +    (void) propertyImpl;
>>> +    numProperties++;
>>> +  }
>>> +
>>> +  ConstantBuilder builder(CGM);
>>> +  auto propertyList = builder.beginStruct();
>>> +  propertyList.addInt(IntTy, numProperties);
>>> +  propertyList.add(NULLPtr);
>>> +  auto properties = propertyList.beginArray(propertyMetadataTy);
>>>
>>>    // Add all of the property methods need adding to the method list and
>>> to the
>>>    // property metadata list.
>>>    for (auto *propertyImpl : OID->property_impls()) {
>>> -    std::vector<llvm::Constant*> Fields;
>>> +    auto fields = properties.beginStruct(propertyMetadataTy);
>>>      ObjCPropertyDecl *property = propertyImpl->getPropertyDecl();
>>>      bool isSynthesized = (propertyImpl->getPropertyImplementation() ==
>>>          ObjCPropertyImplDecl::Synthesize);
>>>      bool isDynamic = (propertyImpl->getPropertyImplementation() ==
>>>          ObjCPropertyImplDecl::Dynamic);
>>>
>>> -    Fields.push_back(MakePropertyEncodingString(property, OID));
>>> -    PushPropertyAttributes(Fields, property, isSynthesized, isDynamic);
>>> +    fields.add(MakePropertyEncodingString(property, OID));
>>> +    PushPropertyAttributes(fields, property, isSynthesized, isDynamic);
>>>      if (ObjCMethodDecl *getter = property->getGetterMethodDecl()) {
>>>        std::string TypeStr;
>>>        Context.getObjCEncodingForMethodDecl(getter,TypeStr);
>>> @@ -2149,11 +2133,11 @@ llvm::Constant *CGObjCGNU::GeneratePrope
>>>          InstanceMethodTypes.push_back(TypeEncoding);
>>>          InstanceMethodSels.push_back(getter->getSelector());
>>>        }
>>> -      Fields.push_back(MakeConstantString(getter->getSelector().ge
>>> tAsString()));
>>> -      Fields.push_back(TypeEncoding);
>>> +      fields.add(MakeConstantString(getter->getSelector().getAsStr
>>> ing()));
>>> +      fields.add(TypeEncoding);
>>>      } else {
>>> -      Fields.push_back(NULLPtr);
>>> -      Fields.push_back(NULLPtr);
>>> +      fields.add(NULLPtr);
>>> +      fields.add(NULLPtr);
>>>      }
>>>      if (ObjCMethodDecl *setter = property->getSetterMethodDecl()) {
>>>        std::string TypeStr;
>>> @@ -2163,26 +2147,18 @@ llvm::Constant *CGObjCGNU::GeneratePrope
>>>          InstanceMethodTypes.push_back(TypeEncoding);
>>>          InstanceMethodSels.push_back(setter->getSelector());
>>>        }
>>> -      Fields.push_back(MakeConstantString(setter->getSelector().ge
>>> tAsString()));
>>> -      Fields.push_back(TypeEncoding);
>>> +      fields.add(MakeConstantString(setter->getSelector().getAsStr
>>> ing()));
>>> +      fields.add(TypeEncoding);
>>>      } else {
>>> -      Fields.push_back(NULLPtr);
>>> -      Fields.push_back(NULLPtr);
>>> +      fields.add(NULLPtr);
>>> +      fields.add(NULLPtr);
>>>      }
>>> -    Properties.push_back(llvm::ConstantStruct::get(PropertyMetadataTy,
>>> Fields));
>>> +    properties.add(fields.finish());
>>>    }
>>> -  llvm::ArrayType *PropertyArrayTy =
>>> -      llvm::ArrayType::get(PropertyMetadataTy, Properties.size());
>>> -  llvm::Constant *PropertyArray = llvm::ConstantArray::get(Prope
>>> rtyArrayTy,
>>> -          Properties);
>>> -  llvm::Constant* PropertyListInitFields[] =
>>> -    {llvm::ConstantInt::get(IntTy, Properties.size()), NULLPtr,
>>> PropertyArray};
>>> -
>>> -  llvm::Constant *PropertyListInit =
>>> -      llvm::ConstantStruct::getAnon(PropertyListInitFields);
>>> -  return new llvm::GlobalVariable(TheModule,
>>> PropertyListInit->getType(), false,
>>> -          llvm::GlobalValue::InternalLinkage, PropertyListInit,
>>> -          ".objc_property_list");
>>> +  propertyList.add(properties.finish());
>>> +
>>> +  return propertyList.finishAndCreateGlobal(".objc_property_list",
>>> +                                            CGM.getPointerAlign());
>>>  }
>>>
>>>  void CGObjCGNU::RegisterAlias(const ObjCCompatibleAliasDecl *OAD) {
>>> @@ -2231,7 +2207,8 @@ void CGObjCGNU::GenerateClass(const ObjC
>>>    SmallVector<llvm::Constant*, 16> IvarTypes;
>>>    SmallVector<llvm::Constant*, 16> IvarOffsets;
>>>
>>> -  std::vector<llvm::Constant*> IvarOffsetValues;
>>> +  ConstantBuilder IvarOffsetBuilder(CGM);
>>> +  auto IvarOffsetValues = IvarOffsetBuilder.beginArray(PtrToIntTy);
>>>    SmallVector<bool, 16> WeakIvars;
>>>    SmallVector<bool, 16> StrongIvars;
>>>
>>> @@ -2275,7 +2252,7 @@ void CGObjCGNU::GenerateClass(const ObjC
>>>            "__objc_ivar_offset_value_" + ClassName +"." +
>>>            IVD->getNameAsString());
>>>        IvarOffsets.push_back(OffsetValue);
>>> -      IvarOffsetValues.push_back(OffsetVar);
>>> +      IvarOffsetValues.add(OffsetVar);
>>>        Qualifiers::ObjCLifetime lt = IVD->getType().getQualifiers()
>>> .getObjCLifetime();
>>>        switch (lt) {
>>>          case Qualifiers::OCL_Strong:
>>> @@ -2294,8 +2271,8 @@ void CGObjCGNU::GenerateClass(const ObjC
>>>    llvm::Constant *StrongIvarBitmap = MakeBitField(StrongIvars);
>>>    llvm::Constant *WeakIvarBitmap = MakeBitField(WeakIvars);
>>>    llvm::GlobalVariable *IvarOffsetArray =
>>> -    MakeGlobalArray(PtrToIntTy, IvarOffsetValues, CGM.getPointerAlign(),
>>> -                    ".ivar.offsets");
>>> +    IvarOffsetValues.finishAndCreateGlobal(".ivar.offsets",
>>> +                                           CGM.getPointerAlign());
>>>
>>>    // Collect information about instance methods
>>>    SmallVector<Selector, 16> InstanceMethodSels;
>>> @@ -2461,21 +2438,18 @@ llvm::Function *CGObjCGNU::ModuleInitFun
>>>      if (StringClass.empty()) StringClass = "NXConstantString";
>>>
>>>      Elements.push_back(MakeConstantString(StringClass,
>>> -                ".objc_static_class_name"));
>>> +                                          ".objc_static_class_name"));
>>>      Elements.push_back(llvm::ConstantArray::get(StaticsArrayTy,
>>> -       ConstantStrings));
>>> -    llvm::StructType *StaticsListTy =
>>> -      llvm::StructType::get(PtrToInt8Ty, StaticsArrayTy, nullptr);
>>> -    llvm::Type *StaticsListPtrTy =
>>> -      llvm::PointerType::getUnqual(StaticsListTy);
>>> -    Statics = MakeGlobal(StaticsListTy, Elements, CGM.getPointerAlign(),
>>> -                         ".objc_statics");
>>> +                                                ConstantStrings));
>>> +    Statics = MakeGlobal(llvm::ConstantStruct::getAnon(Elements),
>>> +                         CGM.getPointerAlign(), ".objc_statics");
>>> +    llvm::Type *StaticsListPtrTy = Statics->getType();
>>>      llvm::ArrayType *StaticsListArrayTy =
>>>        llvm::ArrayType::get(StaticsListPtrTy, 2);
>>>      Elements.clear();
>>>      Elements.push_back(Statics);
>>>      Elements.push_back(llvm::Constant::getNullValue(StaticsListPtrTy));
>>> -    Statics = MakeGlobal(StaticsListArrayTy, Elements,
>>> +    Statics = MakeGlobal(llvm::ConstantArray::get(StaticsListArrayTy,
>>> Elements),
>>>                           CGM.getPointerAlign(), ".objc_statics_ptr");
>>>      Statics = llvm::ConstantExpr::getBitCast(Statics, PtrTy);
>>>    }
>>> @@ -2489,7 +2463,8 @@ llvm::Function *CGObjCGNU::ModuleInitFun
>>>
>>>    Elements.clear();
>>>    // Pointer to an array of selectors used in this module.
>>> -  std::vector<llvm::Constant*> Selectors;
>>> +  ConstantBuilder SelectorBuilder(CGM);
>>> +  auto Selectors = SelectorBuilder.beginArray(SelStructTy);
>>>    std::vector<llvm::GlobalAlias*> SelectorAliases;
>>>    for (SelectorMap::iterator iter = SelectorTable.begin(),
>>>        iterEnd = SelectorTable.end(); iter != iterEnd ; ++iter) {
>>> @@ -2505,10 +2480,10 @@ llvm::Function *CGObjCGNU::ModuleInitFun
>>>        if (!i->first.empty())
>>>          SelectorTypeEncoding = MakeConstantString(i->first,
>>> ".objc_sel_types");
>>>
>>> -      Elements.push_back(SelName);
>>> -      Elements.push_back(SelectorTypeEncoding);
>>> -      Selectors.push_back(llvm::ConstantStruct::get(SelStructTy,
>>> Elements));
>>> -      Elements.clear();
>>> +      auto SelStruct = Selectors.beginStruct(SelStructTy);
>>> +      SelStruct.add(SelName);
>>> +      SelStruct.add(SelectorTypeEncoding);
>>> +      Selectors.add(SelStruct.finish());
>>>
>>>        // Store the selector alias for later replacement
>>>        SelectorAliases.push_back(i->second);
>>> @@ -2519,16 +2494,18 @@ llvm::Function *CGObjCGNU::ModuleInitFun
>>>    // because the selector list has a length field.  Unfortunately, the
>>> GCC
>>>    // runtime decides to ignore the length field and expects a NULL
>>> terminator,
>>>    // and GCC cooperates with this by always setting the length to 0.
>>> -  Elements.push_back(NULLPtr);
>>> -  Elements.push_back(NULLPtr);
>>> -  Selectors.push_back(llvm::ConstantStruct::get(SelStructTy,
>>> Elements));
>>> -  Elements.clear();
>>> +  {
>>> +    auto SelStruct = Selectors.beginStruct(SelStructTy);
>>> +    SelStruct.add(NULLPtr);
>>> +    SelStruct.add(NULLPtr);
>>> +    Selectors.add(SelStruct.finish());
>>> +  }
>>>
>>>    // Number of static selectors
>>>    Elements.push_back(llvm::ConstantInt::get(LongTy, SelectorCount));
>>>    llvm::GlobalVariable *SelectorList =
>>> -      MakeGlobalArray(SelStructTy, Selectors, CGM.getPointerAlign(),
>>> -                      ".objc_selector_list");
>>> +      Selectors.finishAndCreateGlobal(".objc_selector_list",
>>> +                                      CGM.getPointerAlign());
>>>    Elements.push_back(llvm::ConstantExpr::getBitCast(SelectorList,
>>>      SelStructPtrTy));
>>>
>>> @@ -2562,7 +2539,8 @@ llvm::Function *CGObjCGNU::ModuleInitFun
>>>    Elements.push_back(ClassList);
>>>    // Construct the symbol table
>>>    llvm::Constant *SymTab =
>>> -    MakeGlobal(SymTabTy, Elements, CGM.getPointerAlign());
>>> +    MakeGlobal(llvm::ConstantStruct::get(SymTabTy, Elements),
>>> +               CGM.getPointerAlign());
>>>
>>>    // The symbol table is contained in a module which has some
>>> version-checking
>>>    // constants
>>> @@ -2603,7 +2581,9 @@ llvm::Function *CGObjCGNU::ModuleInitFun
>>>          break;
>>>      }
>>>
>>> -  llvm::Value *Module = MakeGlobal(ModuleTy, Elements,
>>> CGM.getPointerAlign());
>>> +  llvm::Value *Module =
>>> +    MakeGlobal(llvm::ConstantStruct::get(ModuleTy, Elements),
>>> +               CGM.getPointerAlign());
>>>
>>>    // Create the load function calling the runtime entry point with the
>>> module
>>>    // structure
>>>
>>> Modified: cfe/trunk/lib/CodeGen/CGOpenMPRuntime.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CG
>>> OpenMPRuntime.cpp?rev=287437&r1=287436&r2=287437&view=diff
>>> ============================================================
>>> ==================
>>> --- cfe/trunk/lib/CodeGen/CGOpenMPRuntime.cpp (original)
>>> +++ cfe/trunk/lib/CodeGen/CGOpenMPRuntime.cpp Sat Nov 19 02:17:24 2016
>>> @@ -15,6 +15,7 @@
>>>  #include "CGCleanup.h"
>>>  #include "CGOpenMPRuntime.h"
>>>  #include "CodeGenFunction.h"
>>> +#include "ConstantBuilder.h"
>>>  #include "clang/AST/Decl.h"
>>>  #include "clang/AST/StmtOpenMP.h"
>>>  #include "llvm/ADT/ArrayRef.h"
>>> @@ -906,18 +907,19 @@ Address CGOpenMPRuntime::getOrCreateDefa
>>>        DefaultOpenMPPSource =
>>>            llvm::ConstantExpr::getBitCast(DefaultOpenMPPSource,
>>> CGM.Int8PtrTy);
>>>      }
>>> -    auto DefaultOpenMPLocation = new llvm::GlobalVariable(
>>> -        CGM.getModule(), IdentTy, /*isConstant*/ true,
>>> -        llvm::GlobalValue::PrivateLinkage, /*Initializer*/ nullptr);
>>> +
>>> +    ConstantBuilder builder(CGM);
>>>
>>> +    auto fields = builder.beginStruct(IdentTy);
>>> +    fields.addInt(CGM.Int32Ty, 0);
>>> +    fields.addInt(CGM.Int32Ty, Flags);
>>> +    fields.addInt(CGM.Int32Ty, 0);
>>> +    fields.addInt(CGM.Int32Ty, 0);
>>> +    fields.add(DefaultOpenMPPSource);
>>> +    auto DefaultOpenMPLocation =
>>> +      fields.finishAndCreateGlobal("", Align, /*isConstant*/ true,
>>> +                                   llvm::GlobalValue::PrivateLinkage);
>>>      DefaultOpenMPLocation->setUnnamedAddr(llvm::GlobalValue::Un
>>> namedAddr::Global);
>>> -    DefaultOpenMPLocation->setAlignment(Align.getQuantity());
>>>
>>> -    llvm::Constant *Zero = llvm::ConstantInt::get(CGM.Int32Ty, 0,
>>> true);
>>> -    llvm::Constant *Values[] = {Zero,
>>> -                                llvm::ConstantInt::get(CGM.Int32Ty,
>>> Flags),
>>> -                                Zero, Zero, DefaultOpenMPPSource};
>>> -    llvm::Constant *Init = llvm::ConstantStruct::get(IdentTy, Values);
>>> -    DefaultOpenMPLocation->setInitializer(Init);
>>>      OpenMPDefaultLocMap[Flags] = Entry = DefaultOpenMPLocation;
>>>    }
>>>    return Address(Entry, Align);
>>> @@ -2810,9 +2812,10 @@ CGOpenMPRuntime::createOffloadingBinaryD
>>>        ".omp_offloading.entries_end");
>>>
>>>    // Create all device images
>>> -  llvm::SmallVector<llvm::Constant *, 4> DeviceImagesEntires;
>>>    auto *DeviceImageTy = cast<llvm::StructType>(
>>>        CGM.getTypes().ConvertTypeForMem(getTgtDeviceImageQTy()));
>>> +  ConstantBuilder DeviceImagesBuilder(CGM);
>>> +  auto DeviceImagesEntries = DeviceImagesBuilder.beginArray
>>> (DeviceImageTy);
>>>
>>>    for (unsigned i = 0; i < Devices.size(); ++i) {
>>>      StringRef T = Devices[i].getTriple();
>>> @@ -2824,22 +2827,19 @@ CGOpenMPRuntime::createOffloadingBinaryD
>>>          M, CGM.Int8Ty, /*isConstant=*/true,
>>> llvm::GlobalValue::ExternalLinkage,
>>>          /*Initializer=*/nullptr, Twine(".omp_offloading.img_end.") +
>>> Twine(T));
>>>
>>> -    llvm::Constant *Dev =
>>> -        llvm::ConstantStruct::get(DeviceImageTy, ImgBegin, ImgEnd,
>>> -                                  HostEntriesBegin, HostEntriesEnd,
>>> nullptr);
>>> -    DeviceImagesEntires.push_back(Dev);
>>> +    auto Dev = DeviceImagesEntries.beginStruct(DeviceImageTy);
>>> +    Dev.add(ImgBegin);
>>> +    Dev.add(ImgEnd);
>>> +    Dev.add(HostEntriesBegin);
>>> +    Dev.add(HostEntriesEnd);
>>> +    DeviceImagesEntries.add(Dev.finish());
>>>    }
>>>
>>>    // Create device images global array.
>>> -  llvm::ArrayType *DeviceImagesInitTy =
>>> -      llvm::ArrayType::get(DeviceImageTy, DeviceImagesEntires.size());
>>> -  llvm::Constant *DeviceImagesInit =
>>> -      llvm::ConstantArray::get(DeviceImagesInitTy,
>>> DeviceImagesEntires);
>>> -
>>> -  llvm::GlobalVariable *DeviceImages = new llvm::GlobalVariable(
>>> -      M, DeviceImagesInitTy, /*isConstant=*/true,
>>> -      llvm::GlobalValue::InternalLinkage, DeviceImagesInit,
>>> -      ".omp_offloading.device_images");
>>> +  llvm::GlobalVariable *DeviceImages =
>>> +    DeviceImagesEntries.finishAndCreateGlobal(".omp_offloading.d
>>> evice_images",
>>> +                                              CGM.getPointerAlign(),
>>> +                                              /*isConstant=*/true);
>>>    DeviceImages->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
>>>
>>>    // This is a Zero array to be used in the creation of the constant
>>> expressions
>>> @@ -2849,16 +2849,18 @@ CGOpenMPRuntime::createOffloadingBinaryD
>>>    // Create the target region descriptor.
>>>    auto *BinaryDescriptorTy = cast<llvm::StructType>(
>>>        CGM.getTypes().ConvertTypeForMem(getTgtBinaryDescriptorQTy()));
>>> -  llvm::Constant *TargetRegionsDescriptorInit =
>>> llvm::ConstantStruct::get(
>>> -      BinaryDescriptorTy, llvm::ConstantInt::get(CGM.Int32Ty,
>>> Devices.size()),
>>> -      llvm::ConstantExpr::getGetElementPtr(DeviceImagesInitTy,
>>> DeviceImages,
>>> -                                           Index),
>>> -      HostEntriesBegin, HostEntriesEnd, nullptr);
>>> -
>>> -  auto *Desc = new llvm::GlobalVariable(
>>> -      M, BinaryDescriptorTy, /*isConstant=*/true,
>>> -      llvm::GlobalValue::InternalLinkage, TargetRegionsDescriptorInit,
>>> -      ".omp_offloading.descriptor");
>>> +  ConstantBuilder DescBuilder(CGM);
>>> +  auto DescInit = DescBuilder.beginStruct(BinaryDescriptorTy);
>>> +  DescInit.addInt(CGM.Int32Ty, Devices.size());
>>> +  DescInit.add(llvm::ConstantExpr::getGetElementPtr(DeviceImag
>>> es->getValueType(),
>>> +                                                    DeviceImages,
>>> +                                                    Index));
>>> +  DescInit.add(HostEntriesBegin);
>>> +  DescInit.add(HostEntriesEnd);
>>> +
>>> +  auto *Desc = DescInit.finishAndCreateGlobal
>>> (".omp_offloading.descriptor",
>>> +                                              CGM.getPointerAlign(),
>>> +                                              /*isConstant=*/true);
>>>
>>>    // Emit code to register or unregister the descriptor at execution
>>>    // startup or closing, respectively.
>>> @@ -2906,19 +2908,24 @@ void CGOpenMPRuntime::createOffloadEntry
>>>    Str->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
>>>    llvm::Constant *StrPtr = llvm::ConstantExpr::getBitCast(Str,
>>> CGM.Int8PtrTy);
>>>
>>> +  // We can't have any padding between symbols, so we need to have
>>> 1-byte
>>> +  // alignment.
>>> +  auto Align = CharUnits::fromQuantity(1);
>>> +
>>>    // Create the entry struct.
>>> -  llvm::Constant *EntryInit = llvm::ConstantStruct::get(
>>> -      TgtOffloadEntryType, AddrPtr, StrPtr,
>>> -      llvm::ConstantInt::get(CGM.SizeTy, Size), nullptr);
>>> -  llvm::GlobalVariable *Entry = new llvm::GlobalVariable(
>>> -      M, TgtOffloadEntryType, true, llvm::GlobalValue::ExternalLinkage,
>>> -      EntryInit, ".omp_offloading.entry");
>>> +  ConstantBuilder EntryBuilder(CGM);
>>> +  auto EntryInit = EntryBuilder.beginStruct(TgtOffloadEntryType);
>>> +  EntryInit.add(AddrPtr);
>>> +  EntryInit.add(StrPtr);
>>> +  EntryInit.addInt(CGM.SizeTy, Size);
>>> +  llvm::GlobalVariable *Entry =
>>> +    EntryInit.finishAndCreateGlobal(".omp_offloading.entry",
>>> +                                    Align,
>>> +                                    /*constant*/ true,
>>>
>>> +                                    llvm::GlobalValue::ExternalLin
>>> kage);
>>>
>>>    // The entry has to be created in the section the linker expects it
>>> to be.
>>>    Entry->setSection(".omp_offloading.entries");
>>> -  // We can't have any padding between symbols, so we need to have
>>> 1-byte
>>> -  // alignment.
>>> -  Entry->setAlignment(1);
>>>  }
>>>
>>>  void CGOpenMPRuntime::createOffloadEntriesAndInfoMetadata() {
>>>
>>> Modified: cfe/trunk/lib/CodeGen/CodeGenModule.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/Co
>>> deGenModule.cpp?rev=287437&r1=287436&r2=287437&view=diff
>>> ============================================================
>>> ==================
>>> --- cfe/trunk/lib/CodeGen/CodeGenModule.cpp (original)
>>> +++ cfe/trunk/lib/CodeGen/CodeGenModule.cpp Sat Nov 19 02:17:24 2016
>>> @@ -24,6 +24,7 @@
>>>  #include "CodeGenFunction.h"
>>>  #include "CodeGenPGO.h"
>>>  #include "CodeGenTBAA.h"
>>> +#include "ConstantBuilder.h"
>>>  #include "CoverageMappingGen.h"
>>>  #include "TargetInfo.h"
>>>  #include "clang/AST/ASTContext.h"
>>> @@ -731,6 +732,8 @@ void CodeGenModule::AddGlobalDtor(llvm::
>>>  }
>>>
>>>  void CodeGenModule::EmitCtorList(CtorList &Fns, const char
>>> *GlobalName) {
>>> +  if (Fns.empty()) return;
>>> +
>>>    // Ctor function type is void()*.
>>>    llvm::FunctionType* CtorFTy = llvm::FunctionType::get(VoidTy, false);
>>>    llvm::Type *CtorPFTy = llvm::PointerType::getUnqual(CtorFTy);
>>> @@ -740,24 +743,22 @@ void CodeGenModule::EmitCtorList(CtorLis
>>>        Int32Ty, llvm::PointerType::getUnqual(CtorFTy), VoidPtrTy,
>>> nullptr);
>>>
>>>    // Construct the constructor and destructor arrays.
>>> -  SmallVector<llvm::Constant *, 8> Ctors;
>>> +  ConstantBuilder builder(*this);
>>> +  auto ctors = builder.beginArray(CtorStructTy);
>>>    for (const auto &I : Fns) {
>>> -    llvm::Constant *S[] = {
>>> -        llvm::ConstantInt::get(Int32Ty, I.Priority, false),
>>> -        llvm::ConstantExpr::getBitCast(I.Initializer, CtorPFTy),
>>> -        (I.AssociatedData
>>> -             ? llvm::ConstantExpr::getBitCast(I.AssociatedData,
>>> VoidPtrTy)
>>> -             : llvm::Constant::getNullValue(VoidPtrTy))};
>>> -    Ctors.push_back(llvm::ConstantStruct::get(CtorStructTy, S));
>>> +    auto ctor = ctors.beginStruct(CtorStructTy);
>>> +    ctor.addInt(Int32Ty, I.Priority);
>>> +    ctor.add(llvm::ConstantExpr::getBitCast(I.Initializer, CtorPFTy));
>>> +    if (I.AssociatedData)
>>> +      ctor.add(llvm::ConstantExpr::getBitCast(I.AssociatedData,
>>> VoidPtrTy));
>>> +    else
>>> +      ctor.addNullPointer(VoidPtrTy);
>>> +    ctors.add(ctor.finish());
>>>    }
>>>
>>> -  if (!Ctors.empty()) {
>>> -    llvm::ArrayType *AT = llvm::ArrayType::get(CtorStructTy,
>>> Ctors.size());
>>> -    new llvm::GlobalVariable(TheModule, AT, false,
>>> -                             llvm::GlobalValue::AppendingLinkage,
>>> -                             llvm::ConstantArray::get(AT, Ctors),
>>> -                             GlobalName);
>>> -  }
>>> +  (void) ctors.finishAndCreateGlobal(GlobalName, getPointerAlign(),
>>> +                                     /*constant*/ false,
>>>
>>> +                                     llvm::GlobalValue::AppendingL
>>> inkage);
>>>    Fns.clear();
>>>  }
>>>
>>> @@ -3190,15 +3191,14 @@ CodeGenModule::GetAddrOfConstantCFString
>>>
>>>    auto *STy = cast<llvm::StructType>(getTypes().ConvertType(CFTy));
>>>
>>> -  llvm::Constant *Fields[4];
>>> +  ConstantBuilder Builder(*this);
>>> +  auto Fields = Builder.beginStruct(STy);
>>>
>>>    // Class pointer.
>>> -  Fields[0] = cast<llvm::ConstantExpr>(CFConstantStringClassRef);
>>> +  Fields.add(cast<llvm::ConstantExpr>(CFConstantStringClassRef));
>>>
>>>    // Flags.
>>> -  llvm::Type *Ty = getTypes().ConvertType(getContext().UnsignedIntTy);
>>> -  Fields[1] = isUTF16 ? llvm::ConstantInt::get(Ty, 0x07d0)
>>> -                      : llvm::ConstantInt::get(Ty, 0x07C8);
>>> +  Fields.addInt(IntTy, isUTF16 ? 0x07d0 : 0x07C8);
>>>
>>>    // String pointer.
>>>    llvm::Constant *C = nullptr;
>>> @@ -3232,25 +3232,24 @@ CodeGenModule::GetAddrOfConstantCFString
>>>                             : "__TEXT,__cstring,cstring_literals");
>>>
>>>    // String.
>>> -  Fields[2] =
>>> +  llvm::Constant *Str =
>>>        llvm::ConstantExpr::getGetElementPtr(GV->getValueType(), GV,
>>> Zeros);
>>>
>>>    if (isUTF16)
>>>      // Cast the UTF16 string to the correct type.
>>> -    Fields[2] = llvm::ConstantExpr::getBitCast(Fields[2], Int8PtrTy);
>>> +    Str = llvm::ConstantExpr::getBitCast(Str, Int8PtrTy);
>>> +  Fields.add(Str);
>>>
>>>    // String length.
>>> -  Ty = getTypes().ConvertType(getContext().LongTy);
>>> -  Fields[3] = llvm::ConstantInt::get(Ty, StringLength);
>>> +  auto Ty = getTypes().ConvertType(getContext().LongTy);
>>> +  Fields.addInt(cast<llvm::IntegerType>(Ty), StringLength);
>>>
>>>    CharUnits Alignment = getPointerAlign();
>>>
>>>    // The struct.
>>> -  C = llvm::ConstantStruct::get(STy, Fields);
>>> -  GV = new llvm::GlobalVariable(getModule(), C->getType(),
>>> /*isConstant=*/false,
>>> -                                llvm::GlobalVariable::PrivateLinkage,
>>> C,
>>> -                                "_unnamed_cfstring_");
>>> -  GV->setAlignment(Alignment.getQuantity());
>>> +  GV = Fields.finishAndCreateGlobal("_unnamed_cfstring_", Alignment,
>>> +                                    /*isConstant=*/false,
>>> +                                    llvm::GlobalVariable::PrivateL
>>> inkage);
>>>    switch (getTriple().getObjectFormat()) {
>>>    case llvm::Triple::UnknownObjectFormat:
>>>      llvm_unreachable("unknown file format");
>>> @@ -3338,19 +3337,18 @@ CodeGenModule::GetAddrOfConstantString(c
>>>      NSConstantStringType = cast<llvm::StructType>(getType
>>> s().ConvertType(NSTy));
>>>    }
>>>
>>> -  llvm::Constant *Fields[3];
>>> +  ConstantBuilder Builder(*this);
>>> +  auto Fields = Builder.beginStruct(NSConstantStringType);
>>>
>>>    // Class pointer.
>>> -  Fields[0] = cast<llvm::ConstantExpr>(V);
>>> +  Fields.add(cast<llvm::ConstantExpr>(V));
>>>
>>>    // String pointer.
>>>    llvm::Constant *C =
>>>
>>>        llvm::ConstantDataArray::getString(VMContext, Entry.first());
>>>
>>> -  llvm::GlobalValue::LinkageTypes Linkage;
>>> -  bool isConstant;
>>> -  Linkage = llvm::GlobalValue::PrivateLinkage;
>>> -  isConstant = !LangOpts.WritableStrings;
>>> +  llvm::GlobalValue::LinkageTypes Linkage =
>>> llvm::GlobalValue::PrivateLinkage;
>>> +  bool isConstant = !LangOpts.WritableStrings;
>>>
>>>    auto *GV = new llvm::GlobalVariable(getModule(), C->getType(),
>>> isConstant,
>>>                                        Linkage, C, ".str");
>>> @@ -3359,20 +3357,17 @@ CodeGenModule::GetAddrOfConstantString(c
>>>    // of the string is via this class initializer.
>>>    CharUnits Align = getContext().getTypeAlignInCha
>>> rs(getContext().CharTy);
>>>    GV->setAlignment(Align.getQuantity());
>>> -  Fields[1] =
>>> -      llvm::ConstantExpr::getGetElementPtr(GV->getValueType(), GV,
>>> Zeros);
>>> +  Fields.add(
>>> +      llvm::ConstantExpr::getGetElementPtr(GV->getValueType(), GV,
>>> Zeros));
>>>
>>>    // String length.
>>> -  llvm::Type *Ty = getTypes().ConvertType(getContext().UnsignedIntTy);
>>> -  Fields[2] = llvm::ConstantInt::get(Ty, StringLength);
>>> +  Fields.addInt(IntTy, StringLength);
>>>
>>>    // The struct.
>>>    CharUnits Alignment = getPointerAlign();
>>> -  C = llvm::ConstantStruct::get(NSConstantStringType, Fields);
>>> -  GV = new llvm::GlobalVariable(getModule(), C->getType(), true,
>>> -                                llvm::GlobalVariable::PrivateLinkage,
>>> C,
>>> -                                "_unnamed_nsstring_");
>>> -  GV->setAlignment(Alignment.getQuantity());
>>> +  GV = Fields.finishAndCreateGlobal("_unnamed_nsstring_", Alignment,
>>> +                                    /*constant*/ true,
>>>
>>> +                                    llvm::GlobalVariable::PrivateL
>>> inkage);
>>>    const char *NSStringSection = "__OBJC,__cstring_object,regul
>>> ar,no_dead_strip";
>>>    const char *NSStringNonFragileABISection =
>>>        "__DATA,__objc_stringobj,regular,no_dead_strip";
>>>
>>> Added: cfe/trunk/lib/CodeGen/ConstantBuilder.h
>>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/Co
>>> nstantBuilder.h?rev=287437&view=auto
>>> ============================================================
>>> ==================
>>> --- cfe/trunk/lib/CodeGen/ConstantBuilder.h (added)
>>> +++ cfe/trunk/lib/CodeGen/ConstantBuilder.h Sat Nov 19 02:17:24 2016
>>> @@ -0,0 +1,274 @@
>>> +//===----- ConstantBuilder.h - Builder for LLVM IR constants ----*- C++
>>> -*-===//
>>> +//
>>> +//                     The LLVM Compiler Infrastructure
>>> +//
>>> +// This file is distributed under the University of Illinois Open Source
>>> +// License. See LICENSE.TXT for details.
>>> +//
>>> +//===------------------------------------------------------
>>> ----------------===//
>>> +//
>>> +// This class provides a convenient interface for building complex
>>> +// global initializers.
>>> +//
>>> +//===------------------------------------------------------
>>> ----------------===//
>>> +
>>> +#ifndef LLVM_CLANG_LIB_CODEGEN_CONSTANTBUILDER_H
>>> +#define LLVM_CLANG_LIB_CODEGEN_CONSTANTBUILDER_H
>>> +
>>> +#include "llvm/ADT/ArrayRef.h"
>>> +#include "llvm/ADT/SmallVector.h"
>>> +#include "llvm/IR/Constants.h"
>>> +
>>> +#include "CodeGenModule.h"
>>> +
>>> +namespace clang {
>>> +namespace CodeGen {
>>> +
>>> +class ConstantBuilder;
>>> +
>>> +/// A convenience builder class for complex constant initializers,
>>> +/// especially for anonymous global structures used by various language
>>> +/// runtimes.
>>> +///
>>> +/// The basic usage pattern is expected to be something like:
>>> +///    ConstantBuilder builder(CGM);
>>> +///    auto toplevel = builder.beginStruct();
>>> +///    toplevel.addInt(CGM.SizeTy, widgets.size());
>>> +///    auto widgetArray = builder.beginArray();
>>> +///    for (auto &widget : widgets) {
>>> +///      auto widgetDesc = widgetArray.beginStruct();
>>> +///      widgetDesc.addInt(CGM.SizeTy, widget.getPower());
>>> +///      widgetDesc.add(CGM.GetAddrOfConstantString(widget.getName()));
>>> +///      widgetDesc.add(CGM.GetAddrOfGlobal(widget.getInitializerDecl
>>> ()));
>>> +///      widgetArray.add(widgetDesc.finish());
>>> +///    }
>>> +///    toplevel.add(widgetArray.finish());
>>> +///    auto global = toplevel.finishAndCreateGlobal("WIDGET_LIST",
>>> Align,
>>> +///                                                 /*constant*/ true);
>>> +class ConstantBuilder {
>>> +  CodeGenModule &CGM;
>>> +  llvm::SmallVector<llvm::Constant*, 16> Buffer;
>>> +  bool Frozen = false;
>>> +
>>> +public:
>>> +  explicit ConstantBuilder(CodeGenModule &CGM) : CGM(CGM) {}
>>> +
>>> +  ~ConstantBuilder() {
>>> +    assert(Buffer.empty() && "didn't claim all values out of buffer");
>>> +  }
>>> +
>>> +  class ArrayBuilder;
>>> +  class StructBuilder;
>>> +
>>> +  class AggregateBuilder {
>>> +  protected:
>>> +    ConstantBuilder &Builder;
>>> +    AggregateBuilder *Parent;
>>> +    size_t Begin;
>>> +    bool Finished = false;
>>> +    bool Frozen = false;
>>> +
>>> +    AggregateBuilder(ConstantBuilder &builder, AggregateBuilder
>>> *parent)
>>> +        : Builder(builder), Parent(parent),
>>> Begin(builder.Buffer.size()) {
>>> +      if (parent) {
>>> +        assert(!parent->Frozen && "parent already has child builder
>>> active");
>>> +        parent->Frozen = true;
>>> +      } else {
>>> +        assert(!builder.Frozen && "builder already has child builder
>>> active");
>>> +        builder.Frozen = true;
>>> +      }
>>> +    }
>>> +
>>> +    ~AggregateBuilder() {
>>> +      assert(Finished && "didn't claim value from aggregate builder");
>>> +    }
>>> +
>>> +    void markFinished() {
>>> +      assert(!Frozen && "child builder still active");
>>> +      assert(!Finished && "builder already finished");
>>> +      Finished = true;
>>> +      if (Parent) {
>>> +        assert(Parent->Frozen &&
>>> +               "parent not frozen while child builder active");
>>> +        Parent->Frozen = false;
>>> +      } else {
>>> +        assert(Builder.Frozen &&
>>> +               "builder not frozen while child builder active");
>>> +        Builder.Frozen = false;
>>> +      }
>>> +    }
>>> +
>>> +  public:
>>> +    // Not copyable.
>>> +    AggregateBuilder(const AggregateBuilder &) = delete;
>>> +    AggregateBuilder &operator=(const AggregateBuilder &) = delete;
>>> +
>>> +    // Movable, mostly to allow returning.  But we have to write this
>>> out
>>> +    // properly to satisfy the assert in the destructor.
>>> +    AggregateBuilder(AggregateBuilder &&other)
>>> +      : Builder(other.Builder), Parent(other.Parent),
>>> Begin(other.Begin),
>>> +        Finished(other.Finished), Frozen(other.Frozen) {
>>> +      other.Finished = false;
>>> +    }
>>> +    AggregateBuilder &operator=(AggregateBuilder &&other) = delete;
>>> +
>>> +    void add(llvm::Constant *value) {
>>> +      assert(!Finished && "cannot add more values after finishing
>>> builder");
>>> +      Builder.Buffer.push_back(value);
>>> +    }
>>> +
>>> +    void addSize(CharUnits size) {
>>> +      add(Builder.CGM.getSize(size));
>>> +    }
>>> +
>>> +    void addInt(llvm::IntegerType *intTy, uint64_t value,
>>> +                bool isSigned = false) {
>>> +      add(llvm::ConstantInt::get(intTy, value, isSigned));
>>> +    }
>>> +
>>> +    void addNullPointer(llvm::PointerType *ptrTy) {
>>> +      add(llvm::ConstantPointerNull::get(ptrTy));
>>> +    }
>>> +
>>> +    ArrayRef<llvm::Constant*> getGEPIndicesToCurrentPosition(
>>> +                             llvm::SmallVectorImpl<llvm::Constant*>
>>> &indices) {
>>> +      getGEPIndicesTo(indices, Builder.Buffer.size());
>>> +      return indices;
>>> +    }
>>> +
>>> +    ArrayBuilder beginArray(llvm::Type *eltTy = nullptr);
>>> +    StructBuilder beginStruct(llvm::StructType *structTy = nullptr);
>>> +
>>> +  private:
>>> +    void getGEPIndicesTo(llvm::SmallVectorImpl<llvm::Constant*>
>>> &indices,
>>> +                         size_t position) const {
>>> +      // Recurse on the parent builder if present.
>>> +      if (Parent) {
>>> +        Parent->getGEPIndicesTo(indices, Begin);
>>> +
>>> +      // Otherwise, add an index to drill into the first level of
>>> pointer.
>>> +      } else {
>>> +        assert(indices.empty());
>>> +        indices.push_back(llvm::ConstantInt::get(Builder.CGM.SizeTy,
>>> 0));
>>> +      }
>>> +
>>> +      assert(position >= Begin);
>>> +      indices.push_back(llvm::ConstantInt::get(Builder.CGM.SizeTy,
>>> +                                               position - Begin));
>>> +    }
>>> +  };
>>> +
>>> +  class ArrayBuilder : public AggregateBuilder {
>>> +    llvm::Type *EltTy;
>>> +    friend class ConstantBuilder;
>>> +    ArrayBuilder(ConstantBuilder &builder, AggregateBuilder *parent,
>>> +                 llvm::Type *eltTy)
>>> +      : AggregateBuilder(builder, parent), EltTy(eltTy) {}
>>> +  public:
>>> +    size_t size() const {
>>> +      assert(!Finished);
>>> +      assert(!Frozen);
>>> +      assert(Begin <= Builder.Buffer.size());
>>> +      return Builder.Buffer.size() - Begin;
>>> +    }
>>> +
>>> +    /// Form an array constant from the values that have been added to
>>> this
>>> +    /// builder.
>>> +    llvm::Constant *finish() {
>>> +      markFinished();
>>> +
>>> +      auto &buffer = Builder.Buffer;
>>> +      assert((Begin < buffer.size() ||
>>> +              (Begin == buffer.size() && EltTy))
>>> +             && "didn't add any array elements without element type");
>>> +      auto elts = llvm::makeArrayRef(buffer).slice(Begin);
>>> +      auto eltTy = EltTy ? EltTy : elts[0]->getType();
>>> +      auto type = llvm::ArrayType::get(eltTy, elts.size());
>>> +      auto constant = llvm::ConstantArray::get(type, elts);
>>> +      buffer.erase(buffer.begin() + Begin, buffer.end());
>>> +      return constant;
>>> +    }
>>> +
>>> +    template <class... As>
>>> +    llvm::GlobalVariable *finishAndCreateGlobal(As &&...args) {
>>> +      assert(!Parent && "finishing non-root builder");
>>> +      return Builder.createGlobal(finish(), std::forward<As>(args)...);
>>> +    }
>>> +  };
>>> +
>>> +  ArrayBuilder beginArray(llvm::Type *eltTy = nullptr) {
>>> +    return ArrayBuilder(*this, nullptr, eltTy);
>>> +  }
>>> +
>>> +  class StructBuilder : public AggregateBuilder {
>>> +    llvm::StructType *Ty;
>>> +    friend class ConstantBuilder;
>>> +    StructBuilder(ConstantBuilder &builder, AggregateBuilder *parent,
>>> +                  llvm::StructType *ty)
>>> +      : AggregateBuilder(builder, parent), Ty(ty) {}
>>> +  public:
>>> +    /// Finish the struct.
>>> +    llvm::Constant *finish(bool packed = false) {
>>> +      markFinished();
>>> +
>>> +      auto &buffer = Builder.Buffer;
>>> +      assert(Begin < buffer.size() && "didn't add any struct
>>> elements?");
>>> +      auto elts = llvm::makeArrayRef(buffer).slice(Begin);
>>> +
>>> +      llvm::Constant *constant;
>>> +      if (Ty) {
>>> +        constant = llvm::ConstantStruct::get(Ty, elts);
>>> +      } else {
>>> +        constant = llvm::ConstantStruct::getAnon(elts, packed);
>>> +      }
>>> +
>>> +      buffer.erase(buffer.begin() + Begin, buffer.end());
>>> +      return constant;
>>> +    }
>>> +
>>> +    template <class... As>
>>> +    llvm::GlobalVariable *finishAndCreateGlobal(As &&...args) {
>>> +      assert(!Parent && "finishing non-root builder");
>>> +      return Builder.createGlobal(finish(), std::forward<As>(args)...);
>>> +    }
>>> +  };
>>> +
>>> +  StructBuilder beginStruct(llvm::StructType *structTy = nullptr) {
>>> +    return StructBuilder(*this, nullptr, structTy);
>>> +  }
>>> +
>>> +  llvm::GlobalVariable *createGlobal(llvm::Constant *initializer,
>>> +                                     StringRef name,
>>> +                                     CharUnits alignment,
>>> +                                     bool constant = false,
>>> +                                     llvm::GlobalValue::LinkageTypes
>>> linkage
>>> +                                       = llvm::GlobalValue::InternalLin
>>> kage,
>>> +                                     unsigned addressSpace = 0) {
>>> +    auto GV = new llvm::GlobalVariable(CGM.getModule(),
>>> +                                       initializer->getType(),
>>> +                                       constant,
>>> +                                       linkage,
>>> +                                       initializer,
>>> +                                       name,
>>> +                                       /*insert before*/ nullptr,
>>> +                                       llvm::GlobalValue::NotThreadL
>>> ocal,
>>> +                                       addressSpace);
>>> +    GV->setAlignment(alignment.getQuantity());
>>> +    return GV;
>>> +  }
>>> +};
>>> +
>>> +inline ConstantBuilder::ArrayBuilder
>>> +ConstantBuilder::AggregateBuilder::beginArray(llvm::Type *eltTy) {
>>> +  return ArrayBuilder(Builder, this, eltTy);
>>> +}
>>> +
>>> +inline ConstantBuilder::StructBuilder
>>> +ConstantBuilder::AggregateBuilder::beginStruct(llvm::StructType
>>> *structTy) {
>>> +  return StructBuilder(Builder, this, structTy);
>>> +}
>>> +
>>> +}  // end namespace CodeGen
>>> +}  // end namespace clang
>>> +
>>> +#endif
>>>
>>>
>>> _______________________________________________
>>> cfe-commits mailing list
>>> cfe-commits at lists.llvm.org
>>> http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
>>>
>>
>>
>>
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