clang/lib/CodeGen/CGBuilder.h

   1 //===-- CGBuilder.h - Choose IRBuilder implementation  ----------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #ifndef LLVM_CLANG_LIB_CODEGEN_CGBUILDER_H
  10 #define LLVM_CLANG_LIB_CODEGEN_CGBUILDER_H
  11
  12 #include "Address.h"
  13 #include "CodeGenTypeCache.h"
  14 #include "llvm/IR/DataLayout.h"
  15 #include "llvm/IR/IRBuilder.h"
  16 #include "llvm/IR/Type.h"
  17
  18 namespace clang {
  19 namespace CodeGen {
  20
  21 class CodeGenFunction;
  22
  23 /// This is an IRBuilder insertion helper that forwards to
  24 /// CodeGenFunction::InsertHelper, which adds necessary metadata to
  25 /// instructions.
  26 class CGBuilderInserter final : public llvm::IRBuilderDefaultInserter {
  27 public:
  28   CGBuilderInserter() = default;
  29   explicit CGBuilderInserter(CodeGenFunction *CGF) : CGF(CGF) {}
  30
  31   /// This forwards to CodeGenFunction::InsertHelper.
  32   void InsertHelper(llvm::Instruction *I, const llvm::Twine &Name,
  33                     llvm::BasicBlock *BB,
  34                     llvm::BasicBlock::iterator InsertPt) const override;
  35
  36 private:
  37   CodeGenFunction *CGF = nullptr;
  38 };
  39
  40 typedef CGBuilderInserter CGBuilderInserterTy;
  41
  42 typedef llvm::IRBuilder<llvm::ConstantFolder, CGBuilderInserterTy>
  43     CGBuilderBaseTy;
  44
  45 class CGBuilderTy : public CGBuilderBaseTy {
  46   /// Storing a reference to the type cache here makes it a lot easier
  47   /// to build natural-feeling, target-specific IR.
  48   const CodeGenTypeCache &TypeCache;
  49
  50 public:
  51   CGBuilderTy(const CodeGenTypeCache &TypeCache, llvm::LLVMContext &C)
  52       : CGBuilderBaseTy(C), TypeCache(TypeCache) {}
  53   CGBuilderTy(const CodeGenTypeCache &TypeCache, llvm::LLVMContext &C,
  54               const llvm::ConstantFolder &F,
  55               const CGBuilderInserterTy &Inserter)
  56       : CGBuilderBaseTy(C, F, Inserter), TypeCache(TypeCache) {}
  57   CGBuilderTy(const CodeGenTypeCache &TypeCache, llvm::Instruction *I)
  58       : CGBuilderBaseTy(I), TypeCache(TypeCache) {}
  59   CGBuilderTy(const CodeGenTypeCache &TypeCache, llvm::BasicBlock *BB)
  60       : CGBuilderBaseTy(BB), TypeCache(TypeCache) {}
  61
  62   llvm::ConstantInt *getSize(CharUnits N) {
  63     return llvm::ConstantInt::get(TypeCache.SizeTy, N.getQuantity());
  64   }
  65   llvm::ConstantInt *getSize(uint64_t N) {
  66     return llvm::ConstantInt::get(TypeCache.SizeTy, N);
  67   }
  68
  69   // Note that we intentionally hide the CreateLoad APIs that don't
  70   // take an alignment.
  71   llvm::LoadInst *CreateLoad(Address Addr, const llvm::Twine &Name = "") {
  72     return CreateAlignedLoad(Addr.getElementType(), Addr.getPointer(),
  73                              Addr.getAlignment().getAsAlign(), Name);
  74   }
  75   llvm::LoadInst *CreateLoad(Address Addr, const char *Name) {
  76     // This overload is required to prevent string literals from
  77     // ending up in the IsVolatile overload.
  78     return CreateAlignedLoad(Addr.getElementType(), Addr.getPointer(),
  79                              Addr.getAlignment().getAsAlign(), Name);
  80   }
  81   llvm::LoadInst *CreateLoad(Address Addr, bool IsVolatile,
  82                              const llvm::Twine &Name = "") {
  83     return CreateAlignedLoad(Addr.getElementType(), Addr.getPointer(),
  84                              Addr.getAlignment().getAsAlign(), IsVolatile,
  85                              Name);
  86   }
  87
  88   using CGBuilderBaseTy::CreateAlignedLoad;
  89   llvm::LoadInst *CreateAlignedLoad(llvm::Type *Ty, llvm::Value *Addr,
  90                                     CharUnits Align,
  91                                     const llvm::Twine &Name = "") {
  92     return CreateAlignedLoad(Ty, Addr, Align.getAsAlign(), Name);
  93   }
  94
  95   // Note that we intentionally hide the CreateStore APIs that don't
  96   // take an alignment.
  97   llvm::StoreInst *CreateStore(llvm::Value *Val, Address Addr,
  98                                bool IsVolatile = false) {
  99     return CreateAlignedStore(Val, Addr.getPointer(),
 100                               Addr.getAlignment().getAsAlign(), IsVolatile);
 101   }
 102
 103   using CGBuilderBaseTy::CreateAlignedStore;
 104   llvm::StoreInst *CreateAlignedStore(llvm::Value *Val, llvm::Value *Addr,
 105                                       CharUnits Align,
 106                                       bool IsVolatile = false) {
 107     return CreateAlignedStore(Val, Addr, Align.getAsAlign(), IsVolatile);
 108   }
 109
 110   // FIXME: these "default-aligned" APIs should be removed,
 111   // but I don't feel like fixing all the builtin code right now.
 112   llvm::StoreInst *CreateDefaultAlignedStore(llvm::Value *Val,
 113                                              llvm::Value *Addr,
 114                                              bool IsVolatile = false) {
 115     return CGBuilderBaseTy::CreateStore(Val, Addr, IsVolatile);
 116   }
 117
 118   /// Emit a load from an i1 flag variable.
 119   llvm::LoadInst *CreateFlagLoad(llvm::Value *Addr,
 120                                  const llvm::Twine &Name = "") {
 121     return CreateAlignedLoad(getInt1Ty(), Addr, CharUnits::One(), Name);
 122   }
 123
 124   /// Emit a store to an i1 flag variable.
 125   llvm::StoreInst *CreateFlagStore(bool Value, llvm::Value *Addr) {
 126     return CreateAlignedStore(getInt1(Value), Addr, CharUnits::One());
 127   }
 128
 129   // Temporarily use old signature; clang will be updated to an Address overload
 130   // in a subsequent patch.
 131   llvm::AtomicCmpXchgInst *
 132   CreateAtomicCmpXchg(llvm::Value *Ptr, llvm::Value *Cmp, llvm::Value *New,
 133                       llvm::AtomicOrdering SuccessOrdering,
 134                       llvm::AtomicOrdering FailureOrdering,
 135                       llvm::SyncScope::ID SSID = llvm::SyncScope::System) {
 136     return CGBuilderBaseTy::CreateAtomicCmpXchg(
 137         Ptr, Cmp, New, llvm::MaybeAlign(), SuccessOrdering, FailureOrdering,
 138         SSID);
 139   }
 140
 141   // Temporarily use old signature; clang will be updated to an Address overload
 142   // in a subsequent patch.
 143   llvm::AtomicRMWInst *
 144   CreateAtomicRMW(llvm::AtomicRMWInst::BinOp Op, llvm::Value *Ptr,
 145                   llvm::Value *Val, llvm::AtomicOrdering Ordering,
 146                   llvm::SyncScope::ID SSID = llvm::SyncScope::System) {
 147     return CGBuilderBaseTy::CreateAtomicRMW(Op, Ptr, Val, llvm::MaybeAlign(),
 148                                             Ordering, SSID);
 149   }
 150
 151   using CGBuilderBaseTy::CreateAddrSpaceCast;
 152   Address CreateAddrSpaceCast(Address Addr, llvm::Type *Ty,
 153                               const llvm::Twine &Name = "") {
 154     return Addr.withPointer(CreateAddrSpaceCast(Addr.getPointer(), Ty, Name),
 155                             Addr.isKnownNonNull());
 156   }
 157
 158   using CGBuilderBaseTy::CreatePointerBitCastOrAddrSpaceCast;
 159   Address CreatePointerBitCastOrAddrSpaceCast(Address Addr, llvm::Type *Ty,
 160                                               llvm::Type *ElementTy,
 161                                               const llvm::Twine &Name = "") {
 162     llvm::Value *Ptr =
 163         CreatePointerBitCastOrAddrSpaceCast(Addr.getPointer(), Ty, Name);
 164     return Address(Ptr, ElementTy, Addr.getAlignment(), Addr.isKnownNonNull());
 165   }
 166
 167   /// Given
 168   ///   %addr = {T1, T2...}* ...
 169   /// produce
 170   ///   %name = getelementptr inbounds %addr, i32 0, i32 index
 171   ///
 172   /// This API assumes that drilling into a struct like this is always an
 173   /// inbounds operation.
 174   using CGBuilderBaseTy::CreateStructGEP;
 175   Address CreateStructGEP(Address Addr, unsigned Index,
 176                           const llvm::Twine &Name = "") {
 177     llvm::StructType *ElTy = cast<llvm::StructType>(Addr.getElementType());
 178     const llvm::DataLayout &DL = BB->getParent()->getParent()->getDataLayout();
 179     const llvm::StructLayout *Layout = DL.getStructLayout(ElTy);
 180     auto Offset = CharUnits::fromQuantity(Layout->getElementOffset(Index));
 181
 182     return Address(
 183         CreateStructGEP(Addr.getElementType(), Addr.getPointer(), Index, Name),
 184         ElTy->getElementType(Index),
 185         Addr.getAlignment().alignmentAtOffset(Offset), Addr.isKnownNonNull());
 186   }
 187
 188   /// Given
 189   ///   %addr = [n x T]* ...
 190   /// produce
 191   ///   %name = getelementptr inbounds %addr, i64 0, i64 index
 192   /// where i64 is actually the target word size.
 193   ///
 194   /// This API assumes that drilling into an array like this is always
 195   /// an inbounds operation.
 196   Address CreateConstArrayGEP(Address Addr, uint64_t Index,
 197                               const llvm::Twine &Name = "") {
 198     llvm::ArrayType *ElTy = cast<llvm::ArrayType>(Addr.getElementType());
 199     const llvm::DataLayout &DL = BB->getParent()->getParent()->getDataLayout();
 200     CharUnits EltSize =
 201         CharUnits::fromQuantity(DL.getTypeAllocSize(ElTy->getElementType()));
 202
 203     return Address(
 204         CreateInBoundsGEP(Addr.getElementType(), Addr.getPointer(),
 205                           {getSize(CharUnits::Zero()), getSize(Index)}, Name),
 206         ElTy->getElementType(),
 207         Addr.getAlignment().alignmentAtOffset(Index * EltSize),
 208         Addr.isKnownNonNull());
 209   }
 210
 211   /// Given
 212   ///   %addr = T* ...
 213   /// produce
 214   ///   %name = getelementptr inbounds %addr, i64 index
 215   /// where i64 is actually the target word size.
 216   Address CreateConstInBoundsGEP(Address Addr, uint64_t Index,
 217                                  const llvm::Twine &Name = "") {
 218     llvm::Type *ElTy = Addr.getElementType();
 219     const llvm::DataLayout &DL = BB->getParent()->getParent()->getDataLayout();
 220     CharUnits EltSize = CharUnits::fromQuantity(DL.getTypeAllocSize(ElTy));
 221
 222     return Address(CreateInBoundsGEP(Addr.getElementType(), Addr.getPointer(),
 223                                      getSize(Index), Name),
 224                    ElTy, Addr.getAlignment().alignmentAtOffset(Index * EltSize),
 225                    Addr.isKnownNonNull());
 226   }
 227
 228   /// Given
 229   ///   %addr = T* ...
 230   /// produce
 231   ///   %name = getelementptr inbounds %addr, i64 index
 232   /// where i64 is actually the target word size.
 233   Address CreateConstGEP(Address Addr, uint64_t Index,
 234                          const llvm::Twine &Name = "") {
 235     const llvm::DataLayout &DL = BB->getParent()->getParent()->getDataLayout();
 236     CharUnits EltSize =
 237         CharUnits::fromQuantity(DL.getTypeAllocSize(Addr.getElementType()));
 238
 239     return Address(CreateGEP(Addr.getElementType(), Addr.getPointer(),
 240                              getSize(Index), Name),
 241                    Addr.getElementType(),
 242                    Addr.getAlignment().alignmentAtOffset(Index * EltSize),
 243                    NotKnownNonNull);
 244   }
 245
 246   /// Create GEP with single dynamic index. The address alignment is reduced
 247   /// according to the element size.
 248   using CGBuilderBaseTy::CreateGEP;
 249   Address CreateGEP(Address Addr, llvm::Value *Index,
 250                     const llvm::Twine &Name = "") {
 251     const llvm::DataLayout &DL = BB->getParent()->getParent()->getDataLayout();
 252     CharUnits EltSize =
 253         CharUnits::fromQuantity(DL.getTypeAllocSize(Addr.getElementType()));
 254
 255     return Address(
 256         CreateGEP(Addr.getElementType(), Addr.getPointer(), Index, Name),
 257         Addr.getElementType(),
 258         Addr.getAlignment().alignmentOfArrayElement(EltSize), NotKnownNonNull);
 259   }
 260
 261   /// Given a pointer to i8, adjust it by a given constant offset.
 262   Address CreateConstInBoundsByteGEP(Address Addr, CharUnits Offset,
 263                                      const llvm::Twine &Name = "") {
 264     assert(Addr.getElementType() == TypeCache.Int8Ty);
 265     return Address(CreateInBoundsGEP(Addr.getElementType(), Addr.getPointer(),
 266                                      getSize(Offset), Name),
 267                    Addr.getElementType(),
 268                    Addr.getAlignment().alignmentAtOffset(Offset),
 269                    Addr.isKnownNonNull());
 270   }
 271   Address CreateConstByteGEP(Address Addr, CharUnits Offset,
 272                              const llvm::Twine &Name = "") {
 273     assert(Addr.getElementType() == TypeCache.Int8Ty);
 274     return Address(CreateGEP(Addr.getElementType(), Addr.getPointer(),
 275                              getSize(Offset), Name),
 276                    Addr.getElementType(),
 277                    Addr.getAlignment().alignmentAtOffset(Offset),
 278                    NotKnownNonNull);
 279   }
 280
 281   using CGBuilderBaseTy::CreateConstInBoundsGEP2_32;
 282   Address CreateConstInBoundsGEP2_32(Address Addr, unsigned Idx0, unsigned Idx1,
 283                                      const llvm::Twine &Name = "") {
 284     const llvm::DataLayout &DL = BB->getParent()->getParent()->getDataLayout();
 285
 286     auto *GEP = cast<llvm::GetElementPtrInst>(CreateConstInBoundsGEP2_32(
 287         Addr.getElementType(), Addr.getPointer(), Idx0, Idx1, Name));
 288     llvm::APInt Offset(
 289         DL.getIndexSizeInBits(Addr.getType()->getPointerAddressSpace()), 0,
 290         /*isSigned=*/true);
 291     if (!GEP->accumulateConstantOffset(DL, Offset))
 292       llvm_unreachable("offset of GEP with constants is always computable");
 293     return Address(GEP, GEP->getResultElementType(),
 294                    Addr.getAlignment().alignmentAtOffset(
 295                        CharUnits::fromQuantity(Offset.getSExtValue())),
 296                    Addr.isKnownNonNull());
 297   }
 298
 299   using CGBuilderBaseTy::CreateMemCpy;
 300   llvm::CallInst *CreateMemCpy(Address Dest, Address Src, llvm::Value *Size,
 301                                bool IsVolatile = false) {
 302     return CreateMemCpy(Dest.getPointer(), Dest.getAlignment().getAsAlign(),
 303                         Src.getPointer(), Src.getAlignment().getAsAlign(), Size,
 304                         IsVolatile);
 305   }
 306   llvm::CallInst *CreateMemCpy(Address Dest, Address Src, uint64_t Size,
 307                                bool IsVolatile = false) {
 308     return CreateMemCpy(Dest.getPointer(), Dest.getAlignment().getAsAlign(),
 309                         Src.getPointer(), Src.getAlignment().getAsAlign(), Size,
 310                         IsVolatile);
 311   }
 312
 313   using CGBuilderBaseTy::CreateMemCpyInline;
 314   llvm::CallInst *CreateMemCpyInline(Address Dest, Address Src, uint64_t Size) {
 315     return CreateMemCpyInline(
 316         Dest.getPointer(), Dest.getAlignment().getAsAlign(), Src.getPointer(),
 317         Src.getAlignment().getAsAlign(), getInt64(Size));
 318   }
 319
 320   using CGBuilderBaseTy::CreateMemMove;
 321   llvm::CallInst *CreateMemMove(Address Dest, Address Src, llvm::Value *Size,
 322                                 bool IsVolatile = false) {
 323     return CreateMemMove(Dest.getPointer(), Dest.getAlignment().getAsAlign(),
 324                          Src.getPointer(), Src.getAlignment().getAsAlign(),
 325                          Size, IsVolatile);
 326   }
 327
 328   using CGBuilderBaseTy::CreateMemSet;
 329   llvm::CallInst *CreateMemSet(Address Dest, llvm::Value *Value,
 330                                llvm::Value *Size, bool IsVolatile = false) {
 331     return CreateMemSet(Dest.getPointer(), Value, Size,
 332                         Dest.getAlignment().getAsAlign(), IsVolatile);
 333   }
 334
 335   using CGBuilderBaseTy::CreateMemSetInline;
 336   llvm::CallInst *CreateMemSetInline(Address Dest, llvm::Value *Value,
 337                                      uint64_t Size) {
 338     return CreateMemSetInline(Dest.getPointer(),
 339                               Dest.getAlignment().getAsAlign(), Value,
 340                               getInt64(Size));
 341   }
 342
 343   using CGBuilderBaseTy::CreatePreserveStructAccessIndex;
 344   Address CreatePreserveStructAccessIndex(Address Addr, unsigned Index,
 345                                           unsigned FieldIndex,
 346                                           llvm::MDNode *DbgInfo) {
 347     llvm::StructType *ElTy = cast<llvm::StructType>(Addr.getElementType());
 348     const llvm::DataLayout &DL = BB->getParent()->getParent()->getDataLayout();
 349     const llvm::StructLayout *Layout = DL.getStructLayout(ElTy);
 350     auto Offset = CharUnits::fromQuantity(Layout->getElementOffset(Index));
 351
 352     return Address(CreatePreserveStructAccessIndex(ElTy, Addr.getPointer(),
 353                                                    Index, FieldIndex, DbgInfo),
 354                    ElTy->getElementType(Index),
 355                    Addr.getAlignment().alignmentAtOffset(Offset));
 356   }
 357
 358   using CGBuilderBaseTy::CreateLaunderInvariantGroup;
 359   Address CreateLaunderInvariantGroup(Address Addr) {
 360     return Addr.withPointer(CreateLaunderInvariantGroup(Addr.getPointer()),
 361                             Addr.isKnownNonNull());
 362   }
 363 };
 364
 365 } // end namespace CodeGen
 366 } // end namespace clang
 367
 368 #endif