llvm/lib/CodeGen/AsmPrinter/DwarfStringPool.h

   1 //===- llvm/CodeGen/DwarfStringPool.h - Dwarf Debug Framework ---*- 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 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_DWARFSTRINGPOOL_H
  10 #define LLVM_LIB_CODEGEN_ASMPRINTER_DWARFSTRINGPOOL_H
  11
  12 #include "llvm/ADT/StringMap.h"
  13 #include "llvm/ADT/StringRef.h"
  14 #include "llvm/CodeGen/DwarfStringPoolEntry.h"
  15 #include "llvm/Support/Allocator.h"
  16
  17 namespace llvm {
  18
  19 class AsmPrinter;
  20 class MCSection;
  21 class MCSymbol;
  22
  23 // Collection of strings for this unit and assorted symbols.
  24 // A String->Symbol mapping of strings used by indirect
  25 // references.
  26 class DwarfStringPool {
  27   using EntryTy = DwarfStringPoolEntry;
  28
  29   StringMap<EntryTy, BumpPtrAllocator &> Pool;
  30   StringRef Prefix;
  31   uint64_t NumBytes = 0;
  32   unsigned NumIndexedStrings = 0;
  33   bool ShouldCreateSymbols;
  34
  35   StringMapEntry<EntryTy> &getEntryImpl(AsmPrinter &Asm, StringRef Str);
  36
  37 public:
  38   using EntryRef = DwarfStringPoolEntryRef;
  39
  40   DwarfStringPool(BumpPtrAllocator &A, AsmPrinter &Asm, StringRef Prefix);
  41
  42   void emitStringOffsetsTableHeader(AsmPrinter &Asm, MCSection *OffsetSection,
  43                                     MCSymbol *StartSym);
  44
  45   void emit(AsmPrinter &Asm, MCSection *StrSection,
  46             MCSection *OffsetSection = nullptr,
  47             bool UseRelativeOffsets = false);
  48
  49   bool empty() const { return Pool.empty(); }
  50
  51   unsigned size() const { return Pool.size(); }
  52
  53   unsigned getNumIndexedStrings() const { return NumIndexedStrings; }
  54
  55   /// Get a reference to an entry in the string pool.
  56   EntryRef getEntry(AsmPrinter &Asm, StringRef Str);
  57
  58   /// Same as getEntry, except that you can use EntryRef::getIndex to obtain a
  59   /// unique ID of this entry (e.g., for use in indexed forms like
  60   /// DW_FORM_strx).
  61   EntryRef getIndexedEntry(AsmPrinter &Asm, StringRef Str);
  62 };
  63
  64 } // end namespace llvm
  65
  66 #endif // LLVM_LIB_CODEGEN_ASMPRINTER_DWARFSTRINGPOOL_H