lld/COFF/TypeMerger.h

   1 //===- TypeMerger.h ---------------------------------------------*- 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 LLD_COFF_TYPEMERGER_H
  10 #define LLD_COFF_TYPEMERGER_H
  11
  12 #include "Config.h"
  13 #include "DebugTypes.h"
  14 #include "lld/Common/Timer.h"
  15 #include "llvm/DebugInfo/CodeView/MergingTypeTableBuilder.h"
  16 #include "llvm/DebugInfo/CodeView/TypeHashing.h"
  17 #include "llvm/Support/Allocator.h"
  18 #include <atomic>
  19
  20 namespace lld::coff {
  21
  22 using llvm::codeview::GloballyHashedType;
  23 using llvm::codeview::TypeIndex;
  24
  25 struct GHashState;
  26
  27 class TypeMerger {
  28 public:
  29   TypeMerger(COFFLinkerContext &ctx, llvm::BumpPtrAllocator &alloc);
  30
  31   ~TypeMerger();
  32
  33   /// Get the type table or the global type table if /DEBUG:GHASH is enabled.
  34   inline llvm::codeview::TypeCollection &getTypeTable() {
  35     assert(!ctx.config.debugGHashes);
  36     return typeTable;
  37   }
  38
  39   /// Get the ID table or the global ID table if /DEBUG:GHASH is enabled.
  40   inline llvm::codeview::TypeCollection &getIDTable() {
  41     assert(!ctx.config.debugGHashes);
  42     return idTable;
  43   }
  44
  45   /// Use global hashes to eliminate duplicate types and identify unique type
  46   /// indices in each TpiSource.
  47   void mergeTypesWithGHash();
  48
  49   /// Map from PDB function id type indexes to PDB function type indexes.
  50   /// Populated after mergeTypesWithGHash.
  51   llvm::DenseMap<TypeIndex, TypeIndex> funcIdToType;
  52
  53   /// Type records that will go into the PDB TPI stream.
  54   llvm::codeview::MergingTypeTableBuilder typeTable;
  55
  56   /// Item records that will go into the PDB IPI stream.
  57   llvm::codeview::MergingTypeTableBuilder idTable;
  58
  59   // When showSummary is enabled, these are histograms of TPI and IPI records
  60   // keyed by type index.
  61   SmallVector<uint32_t, 0> tpiCounts;
  62   SmallVector<uint32_t, 0> ipiCounts;
  63
  64   /// Dependency type sources, such as type servers or PCH object files. These
  65   /// must be processed before objects that rely on them. Set by
  66   /// sortDependencies.
  67   ArrayRef<TpiSource *> dependencySources;
  68
  69   /// Object file sources. These must be processed after dependencySources.
  70   ArrayRef<TpiSource *> objectSources;
  71
  72   /// Sorts the dependencies and reassigns TpiSource indices.
  73   void sortDependencies();
  74
  75 private:
  76   void clearGHashes();
  77
  78   COFFLinkerContext &ctx;
  79 };
  80
  81 } // namespace lld::coff
  82
  83 #endif