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