LLVM 17.0.0git
MCValue.h
Go to the documentation of this file.
1//===-- llvm/MC/MCValue.h - MCValue class -----------------------*- 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// This file contains the declaration of the MCValue class.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_MC_MCVALUE_H
14#define LLVM_MC_MCVALUE_H
15
16#include "llvm/MC/MCExpr.h"
18
19namespace llvm {
20class raw_ostream;
21
22/// This represents an "assembler immediate".
23///
24/// In its most general form, this can hold ":Kind:(SymbolA - SymbolB +
25/// imm64)". Not all targets supports relocations of this general form, but we
26/// need to represent this anyway.
27///
28/// In general both SymbolA and SymbolB will also have a modifier
29/// analogous to the top-level Kind. Current targets are not expected
30/// to make use of both though. The choice comes down to whether
31/// relocation modifiers apply to the closest symbol or the whole
32/// expression.
33///
34/// Note that this class must remain a simple POD value class, because we need
35/// it to live in unions etc.
36class MCValue {
37 const MCSymbolRefExpr *SymA = nullptr, *SymB = nullptr;
38 int64_t Cst = 0;
39 uint32_t RefKind = 0;
40
41public:
42 MCValue() = default;
43 int64_t getConstant() const { return Cst; }
44 const MCSymbolRefExpr *getSymA() const { return SymA; }
45 const MCSymbolRefExpr *getSymB() const { return SymB; }
46 uint32_t getRefKind() const { return RefKind; }
47
48 /// Is this an absolute (as opposed to relocatable) value.
49 bool isAbsolute() const { return !SymA && !SymB; }
50
51 /// Print the value to the stream \p OS.
52 void print(raw_ostream &OS) const;
53
54 /// Print the value to stderr.
55 void dump() const;
56
58
59 static MCValue get(const MCSymbolRefExpr *SymA,
60 const MCSymbolRefExpr *SymB = nullptr,
61 int64_t Val = 0, uint32_t RefKind = 0) {
62 MCValue R;
63 R.Cst = Val;
64 R.SymA = SymA;
65 R.SymB = SymB;
66 R.RefKind = RefKind;
67 return R;
68 }
69
70 static MCValue get(int64_t Val) {
71 MCValue R;
72 R.Cst = Val;
73 R.SymA = nullptr;
74 R.SymB = nullptr;
75 R.RefKind = 0;
76 return R;
77 }
78
79};
80
81} // end namespace llvm
82
83#endif
Represent a reference to a symbol from inside an expression.
Definition: MCExpr.h:192
This represents an "assembler immediate".
Definition: MCValue.h:36
int64_t getConstant() const
Definition: MCValue.h:43
uint32_t getRefKind() const
Definition: MCValue.h:46
MCSymbolRefExpr::VariantKind getAccessVariant() const
Definition: MCValue.cpp:46
static MCValue get(const MCSymbolRefExpr *SymA, const MCSymbolRefExpr *SymB=nullptr, int64_t Val=0, uint32_t RefKind=0)
Definition: MCValue.h:59
const MCSymbolRefExpr * getSymB() const
Definition: MCValue.h:45
void dump() const
Print the value to stderr.
Definition: MCValue.cpp:41
static MCValue get(int64_t Val)
Definition: MCValue.h:70
const MCSymbolRefExpr * getSymA() const
Definition: MCValue.h:44
MCValue()=default
void print(raw_ostream &OS) const
Print the value to the stream OS.
Definition: MCValue.cpp:18
bool isAbsolute() const
Is this an absolute (as opposed to relocatable) value.
Definition: MCValue.h:49
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:52
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18