AddressPool.h revision 341825 
1//===- llvm/CodeGen/AddressPool.h - Dwarf Debug Framework -------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef LLVM_LIB_CODEGEN_ASMPRINTER_ADDRESSPOOL_H
11#define LLVM_LIB_CODEGEN_ASMPRINTER_ADDRESSPOOL_H
12
13#include "llvm/ADT/DenseMap.h"
14
15namespace llvm {
16
17class AsmPrinter;
18class MCSection;
19class MCSymbol;
20
21// Collection of addresses for this unit and assorted labels.
22// A Symbol->unsigned mapping of addresses used by indirect
23// references.
24class AddressPool {
25  struct AddressPoolEntry {
26    unsigned Number;
27    bool TLS;
28
29    AddressPoolEntry(unsigned Number, bool TLS) : Number(Number), TLS(TLS) {}
30  };
31  DenseMap<const MCSymbol *, AddressPoolEntry> Pool;
32
33  /// Record whether the AddressPool has been queried for an address index since
34  /// the last "resetUsedFlag" call. Used to implement type unit fallback - a
35  /// type that references addresses cannot be placed in a type unit when using
36  /// fission.
37  bool HasBeenUsed = false;
38
39public:
40  AddressPool() = default;
41
42  /// Returns the index into the address pool with the given
43  /// label/symbol.
44  unsigned getIndex(const MCSymbol *Sym, bool TLS = false);
45
46  void emit(AsmPrinter &Asm, MCSection *AddrSection);
47
48  bool isEmpty() { return Pool.empty(); }
49
50  bool hasBeenUsed() const { return HasBeenUsed; }
51
52  void resetUsedFlag() { HasBeenUsed = false; }
53
54private:
55  void emitHeader(AsmPrinter &Asm, MCSection *Section);
56};
57
58} // end namespace llvm
59
60#endif // LLVM_LIB_CODEGEN_ASMPRINTER_ADDRESSPOOL_H
61