| //===-- Address.h - An aligned address -------------------------*- C++ -*-===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This class provides a simple wrapper for a pair of a pointer and an |
| // alignment. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_CLANG_LIB_CODEGEN_ADDRESS_H |
| #define LLVM_CLANG_LIB_CODEGEN_ADDRESS_H |
| |
| #include "clang/AST/CharUnits.h" |
| #include "llvm/ADT/PointerIntPair.h" |
| #include "llvm/IR/Constants.h" |
| #include "llvm/Support/MathExtras.h" |
| |
| namespace clang { |
| namespace CodeGen { |
| |
| // Indicates whether a pointer is known not to be null. |
| enum KnownNonNull_t { NotKnownNonNull, KnownNonNull }; |
| |
| /// An aligned address. |
| class Address { |
| llvm::PointerIntPair<llvm::Value *, 1, bool> PointerAndKnownNonNull; |
| llvm::Type *ElementType; |
| CharUnits Alignment; |
| |
| protected: |
| Address(std::nullptr_t) : ElementType(nullptr) {} |
| |
| public: |
| Address(llvm::Value *Pointer, llvm::Type *ElementType, CharUnits Alignment, |
| KnownNonNull_t IsKnownNonNull = NotKnownNonNull) |
| : PointerAndKnownNonNull(Pointer, IsKnownNonNull), |
| ElementType(ElementType), Alignment(Alignment) { |
| assert(Pointer != nullptr && "Pointer cannot be null"); |
| assert(ElementType != nullptr && "Element type cannot be null"); |
| assert(llvm::cast<llvm::PointerType>(Pointer->getType()) |
| ->isOpaqueOrPointeeTypeMatches(ElementType) && |
| "Incorrect pointer element type"); |
| } |
| |
| static Address invalid() { return Address(nullptr); } |
| bool isValid() const { |
| return PointerAndKnownNonNull.getPointer() != nullptr; |
| } |
| |
| llvm::Value *getPointer() const { |
| assert(isValid()); |
| return PointerAndKnownNonNull.getPointer(); |
| } |
| |
| /// Return the type of the pointer value. |
| llvm::PointerType *getType() const { |
| return llvm::cast<llvm::PointerType>(getPointer()->getType()); |
| } |
| |
| /// Return the type of the values stored in this address. |
| llvm::Type *getElementType() const { |
| assert(isValid()); |
| return ElementType; |
| } |
| |
| /// Return the address space that this address resides in. |
| unsigned getAddressSpace() const { |
| return getType()->getAddressSpace(); |
| } |
| |
| /// Return the IR name of the pointer value. |
| llvm::StringRef getName() const { |
| return getPointer()->getName(); |
| } |
| |
| /// Return the alignment of this pointer. |
| CharUnits getAlignment() const { |
| assert(isValid()); |
| return Alignment; |
| } |
| |
| /// Return address with different pointer, but same element type and |
| /// alignment. |
| Address withPointer(llvm::Value *NewPointer, |
| KnownNonNull_t IsKnownNonNull) const { |
| return Address(NewPointer, getElementType(), getAlignment(), |
| IsKnownNonNull); |
| } |
| |
| /// Return address with different alignment, but same pointer and element |
| /// type. |
| Address withAlignment(CharUnits NewAlignment) const { |
| return Address(getPointer(), getElementType(), NewAlignment, |
| isKnownNonNull()); |
| } |
| |
| /// Whether the pointer is known not to be null. |
| KnownNonNull_t isKnownNonNull() const { |
| assert(isValid()); |
| return (KnownNonNull_t)PointerAndKnownNonNull.getInt(); |
| } |
| |
| /// Set the non-null bit. |
| Address setKnownNonNull() { |
| assert(isValid()); |
| PointerAndKnownNonNull.setInt(true); |
| return *this; |
| } |
| }; |
| |
| /// A specialization of Address that requires the address to be an |
| /// LLVM Constant. |
| class ConstantAddress : public Address { |
| ConstantAddress(std::nullptr_t) : Address(nullptr) {} |
| |
| public: |
| ConstantAddress(llvm::Constant *pointer, llvm::Type *elementType, |
| CharUnits alignment) |
| : Address(pointer, elementType, alignment) {} |
| |
| static ConstantAddress invalid() { |
| return ConstantAddress(nullptr); |
| } |
| |
| llvm::Constant *getPointer() const { |
| return llvm::cast<llvm::Constant>(Address::getPointer()); |
| } |
| |
| ConstantAddress getElementBitCast(llvm::Type *ElemTy) const { |
| llvm::Constant *BitCast = llvm::ConstantExpr::getBitCast( |
| getPointer(), ElemTy->getPointerTo(getAddressSpace())); |
| return ConstantAddress(BitCast, ElemTy, getAlignment()); |
| } |
| |
| static bool isaImpl(Address addr) { |
| return llvm::isa<llvm::Constant>(addr.getPointer()); |
| } |
| static ConstantAddress castImpl(Address addr) { |
| return ConstantAddress(llvm::cast<llvm::Constant>(addr.getPointer()), |
| addr.getElementType(), addr.getAlignment()); |
| } |
| }; |
| |
| } |
| |
| // Present a minimal LLVM-like casting interface. |
| template <class U> inline U cast(CodeGen::Address addr) { |
| return U::castImpl(addr); |
| } |
| template <class U> inline bool isa(CodeGen::Address addr) { |
| return U::isaImpl(addr); |
| } |
| |
| } |
| |
| #endif |