1327952Sdim//===- GlobalsStream.cpp - PDB Index of Symbols by Name ---------*- C++ -*-===// 2317017Sdim// 3353358Sdim// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4353358Sdim// See https://llvm.org/LICENSE.txt for license information. 5353358Sdim// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6317017Sdim// 7317017Sdim//===----------------------------------------------------------------------===// 8327952Sdim// 9327952Sdim// The on-disk structores used in this file are based on the reference 10327952Sdim// implementation which is available at 11327952Sdim// https://github.com/Microsoft/microsoft-pdb/blob/master/PDB/dbi/gsi.h 12327952Sdim// 13327952Sdim// When you are reading the reference source code, you'd find the 14327952Sdim// information below useful. 15327952Sdim// 16327952Sdim// - ppdb1->m_fMinimalDbgInfo seems to be always true. 17327952Sdim// - SMALLBUCKETS macro is defined. 18327952Sdim// 19327952Sdim//===----------------------------------------------------------------------===// 20317017Sdim 21317017Sdim#include "llvm/DebugInfo/PDB/Native/GlobalsStream.h" 22344779Sdim 23344779Sdim#include "llvm/DebugInfo/CodeView/RecordName.h" 24344779Sdim#include "llvm/DebugInfo/PDB/Native/Hash.h" 25327952Sdim#include "llvm/DebugInfo/PDB/Native/RawError.h" 26344779Sdim#include "llvm/DebugInfo/PDB/Native/SymbolStream.h" 27317017Sdim#include "llvm/Support/BinaryStreamReader.h" 28317017Sdim#include "llvm/Support/Error.h" 29317017Sdim#include <algorithm> 30317017Sdim 31317017Sdimusing namespace llvm; 32317017Sdimusing namespace llvm::msf; 33317017Sdimusing namespace llvm::pdb; 34317017Sdim 35317017SdimGlobalsStream::GlobalsStream(std::unique_ptr<MappedBlockStream> Stream) 36317017Sdim : Stream(std::move(Stream)) {} 37317017Sdim 38317017SdimGlobalsStream::~GlobalsStream() = default; 39317017Sdim 40317017SdimError GlobalsStream::reload() { 41317017Sdim BinaryStreamReader Reader(*Stream); 42327952Sdim if (auto E = GlobalsTable.read(Reader)) 43327952Sdim return E; 44327952Sdim return Error::success(); 45327952Sdim} 46317017Sdim 47344779Sdimstd::vector<std::pair<uint32_t, codeview::CVSymbol>> 48344779SdimGlobalsStream::findRecordsByName(StringRef Name, 49344779Sdim const SymbolStream &Symbols) const { 50344779Sdim std::vector<std::pair<uint32_t, codeview::CVSymbol>> Result; 51344779Sdim 52344779Sdim // Hash the name to figure out which bucket this goes into. 53344779Sdim size_t ExpandedBucketIndex = hashStringV1(Name) % IPHR_HASH; 54344779Sdim int32_t CompressedBucketIndex = GlobalsTable.BucketMap[ExpandedBucketIndex]; 55344779Sdim if (CompressedBucketIndex == -1) 56344779Sdim return Result; 57344779Sdim 58344779Sdim uint32_t LastBucketIndex = GlobalsTable.HashBuckets.size() - 1; 59344779Sdim uint32_t StartRecordIndex = 60344779Sdim GlobalsTable.HashBuckets[CompressedBucketIndex] / 12; 61344779Sdim uint32_t EndRecordIndex = 0; 62344779Sdim if (LLVM_LIKELY(uint32_t(CompressedBucketIndex) < LastBucketIndex)) { 63344779Sdim EndRecordIndex = GlobalsTable.HashBuckets[CompressedBucketIndex + 1]; 64344779Sdim } else { 65344779Sdim // If this is the last bucket, it consists of all hash records until the end 66344779Sdim // of the HashRecords array. 67344779Sdim EndRecordIndex = GlobalsTable.HashRecords.size() * 12; 68344779Sdim } 69344779Sdim 70344779Sdim EndRecordIndex /= 12; 71344779Sdim 72344779Sdim assert(EndRecordIndex <= GlobalsTable.HashRecords.size()); 73344779Sdim while (StartRecordIndex < EndRecordIndex) { 74344779Sdim PSHashRecord PSH = GlobalsTable.HashRecords[StartRecordIndex]; 75344779Sdim uint32_t Off = PSH.Off - 1; 76344779Sdim codeview::CVSymbol Record = Symbols.readRecord(Off); 77344779Sdim if (codeview::getSymbolName(Record) == Name) 78344779Sdim Result.push_back(std::make_pair(Off, std::move(Record))); 79344779Sdim ++StartRecordIndex; 80344779Sdim } 81344779Sdim return Result; 82344779Sdim} 83344779Sdim 84327952Sdimstatic Error checkHashHdrVersion(const GSIHashHeader *HashHdr) { 85327952Sdim if (HashHdr->VerHdr != GSIHashHeader::HdrVersion) 86327952Sdim return make_error<RawError>( 87327952Sdim raw_error_code::feature_unsupported, 88327952Sdim "Encountered unsupported globals stream version."); 89317017Sdim 90327952Sdim return Error::success(); 91327952Sdim} 92327952Sdim 93327952Sdimstatic Error readGSIHashHeader(const GSIHashHeader *&HashHdr, 94327952Sdim BinaryStreamReader &Reader) { 95327952Sdim if (Reader.readObject(HashHdr)) 96327952Sdim return make_error<RawError>(raw_error_code::corrupt_file, 97327952Sdim "Stream does not contain a GSIHashHeader."); 98327952Sdim 99327952Sdim if (HashHdr->VerSignature != GSIHashHeader::HdrSignature) 100327952Sdim return make_error<RawError>( 101327952Sdim raw_error_code::feature_unsupported, 102327952Sdim "GSIHashHeader signature (0xffffffff) not found."); 103327952Sdim 104327952Sdim return Error::success(); 105327952Sdim} 106327952Sdim 107327952Sdimstatic Error readGSIHashRecords(FixedStreamArray<PSHashRecord> &HashRecords, 108327952Sdim const GSIHashHeader *HashHdr, 109327952Sdim BinaryStreamReader &Reader) { 110327952Sdim if (auto EC = checkHashHdrVersion(HashHdr)) 111317017Sdim return EC; 112317017Sdim 113327952Sdim // HashHdr->HrSize specifies the number of bytes of PSHashRecords we have. 114327952Sdim // Verify that we can read them all. 115327952Sdim if (HashHdr->HrSize % sizeof(PSHashRecord)) 116327952Sdim return make_error<RawError>(raw_error_code::corrupt_file, 117327952Sdim "Invalid HR array size."); 118327952Sdim uint32_t NumHashRecords = HashHdr->HrSize / sizeof(PSHashRecord); 119327952Sdim if (auto EC = Reader.readArray(HashRecords, NumHashRecords)) 120327952Sdim return joinErrors(std::move(EC), 121327952Sdim make_error<RawError>(raw_error_code::corrupt_file, 122327952Sdim "Error reading hash records.")); 123327952Sdim 124327952Sdim return Error::success(); 125327952Sdim} 126327952Sdim 127327952Sdimstatic Error 128327952SdimreadGSIHashBuckets(FixedStreamArray<support::ulittle32_t> &HashBuckets, 129344779Sdim FixedStreamArray<support::ulittle32_t> &HashBitmap, 130344779Sdim const GSIHashHeader *HashHdr, 131344779Sdim MutableArrayRef<int32_t> BucketMap, 132327952Sdim BinaryStreamReader &Reader) { 133327952Sdim if (auto EC = checkHashHdrVersion(HashHdr)) 134317017Sdim return EC; 135317017Sdim 136327952Sdim // Before the actual hash buckets, there is a bitmap of length determined by 137327952Sdim // IPHR_HASH. 138327952Sdim size_t BitmapSizeInBits = alignTo(IPHR_HASH + 1, 32); 139344779Sdim uint32_t NumBitmapEntries = BitmapSizeInBits / 32; 140344779Sdim if (auto EC = Reader.readArray(HashBitmap, NumBitmapEntries)) 141327952Sdim return joinErrors(std::move(EC), 142327952Sdim make_error<RawError>(raw_error_code::corrupt_file, 143327952Sdim "Could not read a bitmap.")); 144344779Sdim uint32_t NumBuckets1 = 0; 145344779Sdim uint32_t CompressedBucketIdx = 0; 146344779Sdim for (uint32_t I = 0; I <= IPHR_HASH; ++I) { 147344779Sdim uint8_t WordIdx = I / 32; 148344779Sdim uint8_t BitIdx = I % 32; 149344779Sdim bool IsSet = HashBitmap[WordIdx] & (1U << BitIdx); 150344779Sdim if (IsSet) { 151344779Sdim ++NumBuckets1; 152344779Sdim BucketMap[I] = CompressedBucketIdx++; 153344779Sdim } else { 154344779Sdim BucketMap[I] = -1; 155344779Sdim } 156344779Sdim } 157344779Sdim 158327952Sdim uint32_t NumBuckets = 0; 159344779Sdim for (uint32_t B : HashBitmap) 160327952Sdim NumBuckets += countPopulation(B); 161327952Sdim 162327952Sdim // Hash buckets follow. 163327952Sdim if (auto EC = Reader.readArray(HashBuckets, NumBuckets)) 164327952Sdim return joinErrors(std::move(EC), 165327952Sdim make_error<RawError>(raw_error_code::corrupt_file, 166327952Sdim "Hash buckets corrupted.")); 167327952Sdim 168317017Sdim return Error::success(); 169317017Sdim} 170317017Sdim 171327952SdimError GSIHashTable::read(BinaryStreamReader &Reader) { 172327952Sdim if (auto EC = readGSIHashHeader(HashHdr, Reader)) 173327952Sdim return EC; 174327952Sdim if (auto EC = readGSIHashRecords(HashRecords, HashHdr, Reader)) 175327952Sdim return EC; 176327952Sdim if (HashHdr->HrSize > 0) 177344779Sdim if (auto EC = readGSIHashBuckets(HashBuckets, HashBitmap, HashHdr, 178344779Sdim BucketMap, Reader)) 179327952Sdim return EC; 180327952Sdim return Error::success(); 181327952Sdim} 182