contrib/llvm-project/llvm/lib/DebugInfo/PDB/Native/HashTable.cpp

   1 //===- HashTable.cpp - PDB Hash Table -------------------------------------===//
   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 #include "llvm/DebugInfo/PDB/Native/HashTable.h"
  10 #include "llvm/ADT/Optional.h"
  11 #include "llvm/DebugInfo/PDB/Native/RawError.h"
  12 #include "llvm/Support/BinaryStreamReader.h"
  13 #include "llvm/Support/BinaryStreamWriter.h"
  14 #include "llvm/Support/Error.h"
  15 #include "llvm/Support/MathExtras.h"
  16 #include <algorithm>
  17 #include <cassert>
  18 #include <cstdint>
  19 #include <utility>
  20
  21 using namespace llvm;
  22 using namespace llvm::pdb;
  23
  24 Error llvm::pdb::readSparseBitVector(BinaryStreamReader &Stream,
  25                                      SparseBitVector<> &V) {
  26   uint32_t NumWords;
  27   if (auto EC = Stream.readInteger(NumWords))
  28     return joinErrors(
  29         std::move(EC),
  30         make_error<RawError>(raw_error_code::corrupt_file,
  31                              "Expected hash table number of words"));
  32
  33   for (uint32_t I = 0; I != NumWords; ++I) {
  34     uint32_t Word;
  35     if (auto EC = Stream.readInteger(Word))
  36       return joinErrors(std::move(EC),
  37                         make_error<RawError>(raw_error_code::corrupt_file,
  38                                              "Expected hash table word"));
  39     for (unsigned Idx = 0; Idx < 32; ++Idx)
  40       if (Word & (1U << Idx))
  41         V.set((I * 32) + Idx);
  42   }
  43   return Error::success();
  44 }
  45
  46 Error llvm::pdb::writeSparseBitVector(BinaryStreamWriter &Writer,
  47                                       SparseBitVector<> &Vec) {
  48   constexpr int BitsPerWord = 8 * sizeof(uint32_t);
  49
  50   int ReqBits = Vec.find_last() + 1;
  51   uint32_t ReqWords = alignTo(ReqBits, BitsPerWord) / BitsPerWord;
  52   if (auto EC = Writer.writeInteger(ReqWords))
  53     return joinErrors(
  54         std::move(EC),
  55         make_error<RawError>(raw_error_code::corrupt_file,
  56                              "Could not write linear map number of words"));
  57
  58   uint32_t Idx = 0;
  59   for (uint32_t I = 0; I != ReqWords; ++I) {
  60     uint32_t Word = 0;
  61     for (uint32_t WordIdx = 0; WordIdx < 32; ++WordIdx, ++Idx) {
  62       if (Vec.test(Idx))
  63         Word |= (1 << WordIdx);
  64     }
  65     if (auto EC = Writer.writeInteger(Word))
  66       return joinErrors(std::move(EC), make_error<RawError>(
  67                                            raw_error_code::corrupt_file,
  68                                            "Could not write linear map word"));
  69   }
  70   return Error::success();
  71 }