LLVM 18.0.0git
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1//===- PublicsStream.cpp - PDB Public Symbol Stream -----------------------===//
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
9// The data structures defined in this file are based on the reference
10// implementation which is available at
11// https://github.com/Microsoft/microsoft-pdb/blob/master/PDB/dbi/gsi.h
13// When you are reading the reference source code, you'd find the
14// information below useful.
16// - ppdb1->m_fMinimalDbgInfo seems to be always true.
17// - SMALLBUCKETS macro is defined.
19// The reference doesn't compile, so I learned just by reading code.
20// It's not guaranteed to be correct.
29#include "llvm/Support/Endian.h"
30#include "llvm/Support/Error.h"
31#include <cstdint>
33using namespace llvm;
34using namespace llvm::msf;
35using namespace llvm::support;
36using namespace llvm::pdb;
38PublicsStream::PublicsStream(std::unique_ptr<MappedBlockStream> Stream)
39 : Stream(std::move(Stream)) {}
43uint32_t PublicsStream::getSymHash() const { return Header->SymHash; }
45 return Header->ISectThunkTable;
48 return Header->OffThunkTable;
51// Publics stream contains fixed-size headers and a serialized hash table.
52// This implementation is not complete yet. It reads till the end of the
53// stream so that we verify the stream is at least not corrupted. However,
54// we skip over the hash table which we believe contains information about
55// public symbols.
57 BinaryStreamReader Reader(*Stream);
59 // Check stream size.
60 if (Reader.bytesRemaining() <
61 sizeof(PublicsStreamHeader) + sizeof(GSIHashHeader))
62 return make_error<RawError>(raw_error_code::corrupt_file,
63 "Publics Stream does not contain a header.");
65 // Read PSGSIHDR struct.
66 if (Reader.readObject(Header))
67 return make_error<RawError>(raw_error_code::corrupt_file,
68 "Publics Stream does not contain a header.");
70 // Read the hash table.
71 if (auto E = PublicsTable.read(Reader))
72 return E;
74 // Something called "address map" follows.
75 uint32_t NumAddressMapEntries = Header->AddrMap / sizeof(uint32_t);
76 if (auto EC = Reader.readArray(AddressMap, NumAddressMapEntries))
77 return joinErrors(std::move(EC),
78 make_error<RawError>(raw_error_code::corrupt_file,
79 "Could not read an address map."));
81 // Something called "thunk map" follows.
82 if (auto EC = Reader.readArray(ThunkMap, Header->NumThunks))
83 return joinErrors(std::move(EC),
84 make_error<RawError>(raw_error_code::corrupt_file,
85 "Could not read a thunk map."));
87 // Something called "section map" follows.
88 if (Reader.bytesRemaining() > 0) {
89 if (auto EC = Reader.readArray(SectionOffsets, Header->NumSections))
90 return joinErrors(std::move(EC),
91 make_error<RawError>(raw_error_code::corrupt_file,
92 "Could not read a section map."));
93 }
95 if (Reader.bytesRemaining() > 0)
96 return make_error<RawError>(raw_error_code::corrupt_file,
97 "Corrupted publics stream.");
98 return Error::success();
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
Provides read only access to a subclass of BinaryStream.
Error readObject(const T *&Dest)
Get a pointer to an object of type T from the underlying stream, as if by memcpy, and store the resul...
uint64_t bytesRemaining() const
Error readArray(ArrayRef< T > &Array, uint32_t NumElements)
Get a reference to a NumElements element array of objects of type T from the underlying stream as if ...
Lightweight error class with error context and mandatory checking.
Definition: Error.h:160
static ErrorSuccess success()
Create a success value.
Definition: Error.h:334
Error read(BinaryStreamReader &Reader)
uint32_t getSymHash() const
uint32_t getThunkTableOffset() const
PublicsStream(std::unique_ptr< msf::MappedBlockStream > Stream)
uint16_t getThunkTableSection() const
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
Error joinErrors(Error E1, Error E2)
Concatenate errors.
Definition: Error.h:431
OutputIt move(R &&Range, OutputIt Out)
Provide wrappers to std::move which take ranges instead of having to pass begin/end explicitly.
Definition: STLExtras.h:1854
Implement std::hash so that hash_code can be used in STL containers.
Definition: BitVector.h:858
Header of the hash tables found in the globals and publics sections.
Definition: RawTypes.h:28
support::ulittle32_t OffThunkTable
Definition: RawTypes.h:271
support::ulittle32_t AddrMap
Definition: RawTypes.h:266
support::ulittle32_t NumThunks
Definition: RawTypes.h:267
support::ulittle32_t SymHash
Definition: RawTypes.h:265
support::ulittle16_t ISectThunkTable
Definition: RawTypes.h:269
support::ulittle32_t NumSections
Definition: RawTypes.h:272