include/llvm/DebugInfo/PDB/Native/TpiHashing.h

   1 //===- TpiHashing.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 LLVM_DEBUGINFO_PDB_TPIHASHING_H
  10 #define LLVM_DEBUGINFO_PDB_TPIHASHING_H
  11
  12 #include "llvm/DebugInfo/CodeView/TypeRecord.h"
  13 #include "llvm/Support/Error.h"
  14
  15 namespace llvm {
  16 namespace pdb {
  17
  18 Expected<uint32_t> hashTypeRecord(const llvm::codeview::CVType &Type);
  19
  20 struct TagRecordHash {
  21   explicit TagRecordHash(codeview::ClassRecord CR, uint32_t Full,
  22                          uint32_t Forward)
  23       : FullRecordHash(Full), ForwardDeclHash(Forward), Class(std::move(CR)) {
  24     State = 0;
  25   }
  26
  27   explicit TagRecordHash(codeview::EnumRecord ER, uint32_t Full,
  28                          uint32_t Forward)
  29       : FullRecordHash(Full), ForwardDeclHash(Forward), Enum(std::move(ER)) {
  30     State = 1;
  31   }
  32
  33   explicit TagRecordHash(codeview::UnionRecord UR, uint32_t Full,
  34                          uint32_t Forward)
  35       : FullRecordHash(Full), ForwardDeclHash(Forward), Union(std::move(UR)) {
  36     State = 2;
  37   }
  38
  39   uint32_t FullRecordHash;
  40   uint32_t ForwardDeclHash;
  41
  42   codeview::TagRecord &getRecord() {
  43     switch (State) {
  44     case 0:
  45       return Class;
  46     case 1:
  47       return Enum;
  48     case 2:
  49       return Union;
  50     }
  51     llvm_unreachable("unreachable!");
  52   }
  53
  54 private:
  55   union {
  56     codeview::ClassRecord Class;
  57     codeview::EnumRecord Enum;
  58     codeview::UnionRecord Union;
  59   };
  60
  61   uint8_t State = 0;
  62 };
  63
  64 /// Given a CVType referring to a class, structure, union, or enum, compute
  65 /// the hash of its forward decl and full decl.
  66 Expected<TagRecordHash> hashTagRecord(const codeview::CVType &Type);
  67
  68 } // end namespace pdb
  69 } // end namespace llvm
  70
  71 #endif // LLVM_DEBUGINFO_PDB_TPIHASHING_H