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//===-- llvm/MC/MCValue.h - MCValue class -----------------------*- C++ -*-===//
// The LLVM Compiler Infrastructure
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
// This file contains the declaration of the MCValue class.
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Support/DataTypes.h"
#include <cassert>
namespace llvm {
class MCAsmInfo;
class raw_ostream;
/// MCValue - This represents an "assembler immediate". In its most
/// general form, this can hold ":Kind:(SymbolA - SymbolB + imm64)".
/// Not all targets supports relocations of this general form, but we
/// need to represent this anyway.
/// In general both SymbolA and SymbolB will also have a modifier
/// analogous to the top-level Kind. Current targets are not expected
/// to make use of both though. The choice comes down to whether
/// relocation modifiers apply to the closest symbol or the whole
/// expression.
/// In the general form, SymbolB can only be defined if SymbolA is, and both
/// must be in the same (non-external) section. The latter constraint is not
/// enforced, since a symbol's section may not be known at construction.
/// Note that this class must remain a simple POD value class, because we need
/// it to live in unions etc.
class MCValue {
const MCSymbolRefExpr *SymA, *SymB;
int64_t Cst;
uint32_t RefKind;
int64_t getConstant() const { return Cst; }
const MCSymbolRefExpr *getSymA() const { return SymA; }
const MCSymbolRefExpr *getSymB() const { return SymB; }
uint32_t getRefKind() const { return RefKind; }
/// isAbsolute - Is this an absolute (as opposed to relocatable) value.
bool isAbsolute() const { return !SymA && !SymB; }
/// print - Print the value to the stream \p OS.
void print(raw_ostream &OS, const MCAsmInfo *MAI) const;
/// dump - Print the value to stderr.
void dump() const;
MCSymbolRefExpr::VariantKind getAccessVariant() const;
static MCValue get(const MCSymbolRefExpr *SymA,
const MCSymbolRefExpr *SymB = nullptr,
int64_t Val = 0, uint32_t RefKind = 0) {
MCValue R;
assert((!SymB || SymA) && "Invalid relocatable MCValue!");
R.Cst = Val;
R.SymA = SymA;
R.SymB = SymB;
R.RefKind = RefKind;
return R;
static MCValue get(int64_t Val) {
MCValue R;
R.Cst = Val;
R.SymA = nullptr;
R.SymB = nullptr;
R.RefKind = 0;
return R;
} // end namespace llvm