llvm-project/clang/lib/CodeGen/Address.h

120 lines
3.3 KiB
C++

//===-- Address.h - An aligned address -------------------------*- 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 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 "llvm/IR/Constants.h"
#include "clang/AST/CharUnits.h"
namespace clang {
namespace CodeGen {
/// An aligned address.
class Address {
llvm::Value *Pointer;
CharUnits Alignment;
public:
Address(llvm::Value *pointer, CharUnits alignment)
: Pointer(pointer), Alignment(alignment) {
assert((!alignment.isZero() || pointer == nullptr) &&
"creating valid address with invalid alignment");
}
static Address invalid() { return Address(nullptr, CharUnits()); }
bool isValid() const { return Pointer != nullptr; }
llvm::Value *getPointer() const {
assert(isValid());
return Pointer;
}
/// 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.
///
/// When IR pointer types lose their element type, we should simply
/// store it in Address instead for the convenience of writing code.
llvm::Type *getElementType() const {
return getType()->getElementType();
}
/// 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;
}
};
/// A specialization of Address that requires the address to be an
/// LLVM Constant.
class ConstantAddress : public Address {
public:
ConstantAddress(llvm::Constant *pointer, CharUnits alignment)
: Address(pointer, alignment) {}
static ConstantAddress invalid() {
return ConstantAddress(nullptr, CharUnits());
}
llvm::Constant *getPointer() const {
return llvm::cast<llvm::Constant>(Address::getPointer());
}
ConstantAddress getBitCast(llvm::Type *ty) const {
return ConstantAddress(llvm::ConstantExpr::getBitCast(getPointer(), ty),
getAlignment());
}
ConstantAddress getElementBitCast(llvm::Type *ty) const {
return getBitCast(ty->getPointerTo(getAddressSpace()));
}
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.getAlignment());
}
};
}
}
namespace llvm {
// Present a minimal LLVM-like casting interface.
template <class U> inline U cast(clang::CodeGen::Address addr) {
return U::castImpl(addr);
}
template <class U> inline bool isa(clang::CodeGen::Address addr) {
return U::isaImpl(addr);
}
}
#endif