diff options
| -rw-r--r-- | lld/COFF/Writer.cpp | 64 |
1 files changed, 14 insertions, 50 deletions
diff --git a/lld/COFF/Writer.cpp b/lld/COFF/Writer.cpp index b7665f085dd..bb621eb97f5 100644 --- a/lld/COFF/Writer.cpp +++ b/lld/COFF/Writer.cpp @@ -28,7 +28,6 @@ #include "llvm/Support/Parallel.h" #include "llvm/Support/Path.h" #include "llvm/Support/RandomNumberGenerator.h" -#include "llvm/Support/xxhash.h" #include <algorithm> #include <cstdio> #include <map> @@ -72,18 +71,11 @@ public: uint64_t Offs = OS->getFileOff() + (Record->getRVA() - OS->getRVA()); D->PointerToRawData = Offs; - TimeDateStamps.push_back(&D->TimeDateStamp); ++D; } } - void setTimeDateStamp(uint32_t TimeDateStamp) { - for (support::ulittle32_t *TDS : TimeDateStamps) - *TDS = TimeDateStamp; - } - private: - mutable std::vector<support::ulittle32_t *> TimeDateStamps; const std::vector<Chunk *> &Records; }; @@ -165,7 +157,7 @@ private: RVATableChunk *GuardFidsTable = nullptr; RVATableChunk *SEHTable = nullptr; - DebugDirectoryChunk *DebugDirectory = nullptr; + Chunk *DebugDirectory = nullptr; std::vector<Chunk *> DebugRecords; CVDebugRecordChunk *BuildId = nullptr; Optional<codeview::DebugInfo> PreviousBuildId; @@ -1034,50 +1026,22 @@ void Writer::writeSections() { } void Writer::writeBuildId() { - // There are two important parts to the build ID. - // 1) If building with debug info, the COFF debug directory contains a - // timestamp as well as a Guid and Age of the PDB. - // 2) In all cases, the PE COFF file header also contains a timestamp. - // For reproducibility, instead of a timestamp we want to use a hash of the - // binary, however when building with debug info the hash needs to take into - // account the debug info, since it's possible to add blank lines to a file - // which causes the debug info to change but not the generated code. - // - // To handle this, we first set the Guid and Age in the debug directory (but - // only if we're doing a debug build). Then, we hash the binary (thus causing - // the hash to change if only the debug info changes, since the Age will be - // different). Finally, we write that hash into the debug directory (if - // present) as well as the COFF file header (always). - if (Config->Debug) { - assert(BuildId && "BuildId is not set!"); - if (PreviousBuildId.hasValue()) { - *BuildId->BuildId = *PreviousBuildId; - BuildId->BuildId->PDB70.Age = BuildId->BuildId->PDB70.Age + 1; - } else { - BuildId->BuildId->Signature.CVSignature = OMF::Signature::PDB70; - BuildId->BuildId->PDB70.Age = 1; - llvm::getRandomBytes(BuildId->BuildId->PDB70.Signature, 16); - } - } - - // At this point the only fields in the COFF file which remain unset are the - // "timestamp" in the COFF file header, and the ones in the coff debug - // directory. Now we can hash the file and write that hash to the various - // timestamp fields in the file. - StringRef OutputFileData( - reinterpret_cast<const char *>(Buffer->getBufferStart()), - Buffer->getBufferSize()); + // If we're not writing a build id (e.g. because /debug is not specified), + // then just return; + if (!Config->Debug) + return; - uint32_t Hash = static_cast<uint32_t>(xxHash64(OutputFileData)); + assert(BuildId && "BuildId is not set!"); - if (DebugDirectory) - DebugDirectory->setTimeDateStamp(Hash); + if (PreviousBuildId.hasValue()) { + *BuildId->BuildId = *PreviousBuildId; + BuildId->BuildId->PDB70.Age = BuildId->BuildId->PDB70.Age + 1; + return; + } - uint8_t *Buf = Buffer->getBufferStart(); - Buf += DOSStubSize + sizeof(PEMagic); - object::coff_file_header *CoffHeader = - reinterpret_cast<coff_file_header *>(Buf); - CoffHeader->TimeDateStamp = Hash; + BuildId->BuildId->Signature.CVSignature = OMF::Signature::PDB70; + BuildId->BuildId->PDB70.Age = 1; + llvm::getRandomBytes(BuildId->BuildId->PDB70.Signature, 16); } // Sort .pdata section contents according to PE/COFF spec 5.5. |
