Index: lld/trunk/COFF/PDB.h
===================================================================
--- lld/trunk/COFF/PDB.h
+++ lld/trunk/COFF/PDB.h
@@ -27,7 +27,7 @@
void createPDB(SymbolTable *Symtab,
llvm::ArrayRef<OutputSection *> OutputSections,
llvm::ArrayRef<uint8_t> SectionTable,
- const llvm::codeview::DebugInfo *DI);
+ const llvm::codeview::DebugInfo &BuildId);
}
}
Index: lld/trunk/COFF/PDB.cpp
===================================================================
--- lld/trunk/COFF/PDB.cpp
+++ lld/trunk/COFF/PDB.cpp
@@ -76,7 +76,7 @@
IDTable(Alloc) {}
/// Emit the basic PDB structure: initial streams, headers, etc.
- void initialize(const llvm::codeview::DebugInfo *DI);
+ void initialize(const llvm::codeview::DebugInfo &BuildId);
/// Link CodeView from each object file in the symbol table into the PDB.
void addObjectsToPDB();
@@ -808,15 +808,15 @@
void coff::createPDB(SymbolTable *Symtab,
ArrayRef<OutputSection *> OutputSections,
ArrayRef<uint8_t> SectionTable,
- const llvm::codeview::DebugInfo *DI) {
+ const llvm::codeview::DebugInfo &BuildId) {
PDBLinker PDB(Symtab);
- PDB.initialize(DI);
+ PDB.initialize(BuildId);
PDB.addObjectsToPDB();
PDB.addSections(OutputSections, SectionTable);
PDB.commit();
}
-void PDBLinker::initialize(const llvm::codeview::DebugInfo *DI) {
+void PDBLinker::initialize(const llvm::codeview::DebugInfo &BuildId) {
ExitOnErr(Builder.initialize(4096)); // 4096 is blocksize
// Create streams in MSF for predefined streams, namely
@@ -826,17 +826,17 @@
// Add an Info stream.
auto &InfoBuilder = Builder.getInfoBuilder();
- InfoBuilder.setAge(DI ? DI->PDB70.Age : 0);
+ InfoBuilder.setAge(BuildId.PDB70.Age);
- GUID uuid{};
- if (DI)
- memcpy(&uuid, &DI->PDB70.Signature, sizeof(uuid));
+ GUID uuid;
+ memcpy(&uuid, &BuildId.PDB70.Signature, sizeof(uuid));
InfoBuilder.setGuid(uuid);
InfoBuilder.setSignature(time(nullptr));
InfoBuilder.setVersion(pdb::PdbRaw_ImplVer::PdbImplVC70);
// Add an empty DBI stream.
pdb::DbiStreamBuilder &DbiBuilder = Builder.getDbiBuilder();
+ DbiBuilder.setAge(BuildId.PDB70.Age);
DbiBuilder.setVersionHeader(pdb::PdbDbiV70);
ExitOnErr(DbiBuilder.addDbgStream(pdb::DbgHeaderType::NewFPO, {}));
}
Index: lld/trunk/COFF/Writer.cpp
===================================================================
--- lld/trunk/COFF/Writer.cpp
+++ lld/trunk/COFF/Writer.cpp
@@ -20,6 +20,7 @@
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/StringSwitch.h"
+#include "llvm/Support/BinaryStreamReader.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Endian.h"
#include "llvm/Support/FileOutputBuffer.h"
@@ -92,19 +93,17 @@
void writeTo(uint8_t *B) const override {
// Save off the DebugInfo entry to backfill the file signature (build id)
// in Writer::writeBuildId
- DI = reinterpret_cast<codeview::DebugInfo *>(B + OutputSectionOff);
-
- DI->Signature.CVSignature = OMF::Signature::PDB70;
+ BuildId = reinterpret_cast<codeview::DebugInfo *>(B + OutputSectionOff);
// variable sized field (PDB Path)
- auto *P = reinterpret_cast<char *>(B + OutputSectionOff + sizeof(*DI));
+ char *P = reinterpret_cast<char *>(B + OutputSectionOff + sizeof(*BuildId));
if (!PDBAbsPath.empty())
memcpy(P, PDBAbsPath.data(), PDBAbsPath.size());
P[PDBAbsPath.size()] = '\0';
}
SmallString<128> PDBAbsPath;
- mutable codeview::DebugInfo *DI = nullptr;
+ mutable codeview::DebugInfo *BuildId = nullptr;
};
// The writer writes a SymbolTable result to a file.
@@ -126,8 +125,8 @@
void fixSafeSEHSymbols();
void setSectionPermissions();
void writeSections();
- void sortExceptionTable();
void writeBuildId();
+ void sortExceptionTable();
llvm::Optional<coff_symbol16> createSymbol(Defined *D);
size_t addEntryToStringTable(StringRef Str);
@@ -153,6 +152,7 @@
Chunk *DebugDirectory = nullptr;
std::vector<Chunk *> DebugRecords;
CVDebugRecordChunk *BuildId = nullptr;
+ Optional<codeview::DebugInfo> PreviousBuildId;
ArrayRef<uint8_t> SectionTable;
uint64_t FileSize;
@@ -220,6 +220,65 @@
} // namespace coff
} // namespace lld
+// PDBs are matched against executables using a build id which consists of three
+// components:
+// 1. A 16-bit GUID
+// 2. An age
+// 3. A time stamp.
+//
+// Debuggers and symbol servers match executables against debug info by checking
+// each of these components of the EXE/DLL against the corresponding value in
+// the PDB and failing a match if any of the components differ. In the case of
+// symbol servers, symbols are cached in a folder that is a function of the
+// GUID. As a result, in order to avoid symbol cache pollution where every
+// incremental build copies a new PDB to the symbol cache, we must try to re-use
+// the existing GUID if one exists, but bump the age. This way the match will
+// fail, so the symbol cache knows to use the new PDB, but the GUID matches, so
+// it overwrites the existing item in the symbol cache rather than making a new
+// one.
+static Optional<codeview::DebugInfo> loadExistingBuildId(StringRef Path) {
+ // We don't need to incrementally update a previous build id if we're not
+ // writing codeview debug info.
+ if (!Config->Debug)
+ return None;
+
+ auto ExpectedBinary = llvm::object::createBinary(Path);
+ if (!ExpectedBinary) {
+ consumeError(ExpectedBinary.takeError());
+ return None;
+ }
+
+ auto Binary = std::move(*ExpectedBinary);
+ if (!Binary.getBinary()->isCOFF())
+ return None;
+
+ std::error_code EC;
+ COFFObjectFile File(Binary.getBinary()->getMemoryBufferRef(), EC);
+ if (EC)
+ return None;
+
+ // If the machine of the binary we're outputting doesn't match the machine
+ // of the existing binary, don't try to re-use the build id.
+ if (File.is64() != Config->is64() || File.getMachine() != Config->Machine)
+ return None;
+
+ for (const auto &DebugDir : File.debug_directories()) {
+ if (DebugDir.Type != IMAGE_DEBUG_TYPE_CODEVIEW)
+ continue;
+
+ const codeview::DebugInfo *ExistingDI = nullptr;
+ StringRef PDBFileName;
+ if (auto EC = File.getDebugPDBInfo(ExistingDI, PDBFileName))
+ return None;
+ // We only support writing PDBs in v70 format. So if this is not a build
+ // id that we recognize / support, ignore it.
+ if (ExistingDI->Signature.CVSignature != OMF::Signature::PDB70)
+ return None;
+ return *ExistingDI;
+ }
+ return None;
+}
+
// The main function of the writer.
void Writer::run() {
createSections();
@@ -232,6 +291,10 @@
removeEmptySections();
setSectionPermissions();
createSymbolAndStringTable();
+
+ // We must do this before opening the output file, as it depends on being able
+ // to read the contents of the existing output file.
+ PreviousBuildId = loadExistingBuildId(Config->OutputFile);
openFile(Config->OutputFile);
if (Config->is64()) {
writeHeader<pe32plus_header>();
@@ -244,10 +307,9 @@
writeBuildId();
if (!Config->PDBPath.empty() && Config->Debug) {
- const llvm::codeview::DebugInfo *DI = nullptr;
- if (Config->DebugTypes & static_cast<unsigned>(coff::DebugType::CV))
- DI = BuildId->DI;
- createPDB(Symtab, OutputSections, SectionTable, DI);
+
+ assert(BuildId);
+ createPDB(Symtab, OutputSections, SectionTable, *BuildId->BuildId);
}
writeMapFile(OutputSections);
@@ -311,13 +373,13 @@
if (Config->Debug) {
DebugDirectory = make<DebugDirectoryChunk>(DebugRecords);
- // TODO(compnerd) create a coffgrp entry if DebugType::CV is not enabled
- if (Config->DebugTypes & static_cast<unsigned>(coff::DebugType::CV)) {
- auto *Chunk = make<CVDebugRecordChunk>();
-
- BuildId = Chunk;
- DebugRecords.push_back(Chunk);
- }
+ // Make a CVDebugRecordChunk even when /DEBUG:CV is not specified. We
+ // output a PDB no matter what, and this chunk provides the only means of
+ // allowing a debugger to match a PDB and an executable. So we need it even
+ // if we're ultimately not going to write CodeView data to the PDB.
+ auto *CVChunk = make<CVDebugRecordChunk>();
+ BuildId = CVChunk;
+ DebugRecords.push_back(CVChunk);
RData->addChunk(DebugDirectory);
for (Chunk *C : DebugRecords)
@@ -782,6 +844,25 @@
}
}
+void Writer::writeBuildId() {
+ // If we're not writing a build id (e.g. because /debug is not specified),
+ // then just return;
+ if (!Config->Debug)
+ return;
+
+ assert(BuildId && "BuildId is not set!");
+
+ if (PreviousBuildId.hasValue()) {
+ *BuildId->BuildId = *PreviousBuildId;
+ BuildId->BuildId->PDB70.Age = BuildId->BuildId->PDB70.Age + 1;
+ return;
+ }
+
+ 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.
void Writer::sortExceptionTable() {
OutputSection *Sec = findSection(".pdata");
@@ -805,26 +886,6 @@
errs() << "warning: don't know how to handle .pdata.\n";
}
-// Backfill the CVSignature in a PDB70 Debug Record. This backfilling allows us
-// to get reproducible builds.
-void Writer::writeBuildId() {
- // There is nothing to backfill if BuildId was not setup.
- if (BuildId == nullptr)
- return;
-
- assert(BuildId->DI->Signature.CVSignature == OMF::Signature::PDB70 &&
- "only PDB 7.0 is supported");
- assert(sizeof(BuildId->DI->PDB70.Signature) == 16 &&
- "signature size mismatch");
-
- // Compute an MD5 hash.
- ArrayRef<uint8_t> Buf(Buffer->getBufferStart(), Buffer->getBufferEnd());
- memcpy(BuildId->DI->PDB70.Signature, MD5::hash(Buf).data(), 16);
-
- // TODO(compnerd) track the Age
- BuildId->DI->PDB70.Age = 1;
-}
-
OutputSection *Writer::findSection(StringRef Name) {
for (OutputSection *Sec : OutputSections)
if (Sec->getName() == Name)
Index: lld/trunk/test/COFF/pdb-diff.test
===================================================================
--- lld/trunk/test/COFF/pdb-diff.test
+++ lld/trunk/test/COFF/pdb-diff.test
@@ -4,8 +4,11 @@
file with LLD and compare the two PDBs. Since the baseline object file and
PDB are already checked in, we just run LLD on the object file.
-RUN: lld-link /debug /pdb:%T/pdb-diff-lld.pdb /nodefaultlib /entry:main %S/Inputs/pdb-diff.obj
-RUN: llvm-pdbutil diff -result -values=false -left-bin-root=%S -right-bin-root=D:/src/llvm-mono/lld/test/COFF/ %T/pdb-diff-lld.pdb %S/Inputs/pdb-diff-cl.pdb | FileCheck %s
+RUN: rm -f %T/pdb-diff-lld.pdb %T/pdb-diff-lld.exe
+RUN: lld-link /debug /pdb:%T/pdb-diff-lld.pdb /out:%T/pdb-diff-lld.exe /nodefaultlib \
+RUN: /entry:main %S/Inputs/pdb-diff.obj
+RUN: llvm-pdbutil diff -result -values=false -left-bin-root=%S -right-bin-root=D:/src/llvm-mono/lld/test/COFF/ \
+RUN: %T/pdb-diff-lld.pdb %S/Inputs/pdb-diff-cl.pdb | FileCheck %s
CHECK: ----------------------
CHECK-NEXT: | MSF Super Block |
Index: lld/trunk/test/COFF/pdb-none.test
===================================================================
--- lld/trunk/test/COFF/pdb-none.test
+++ lld/trunk/test/COFF/pdb-none.test
@@ -1,12 +1,13 @@
# RUN: yaml2obj < %p/Inputs/pdb1.yaml > %t1.obj
# RUN: yaml2obj < %p/Inputs/pdb2.yaml > %t2.obj
+# RUN: rm -f %t.pdb %t.dll
# RUN: lld-link /debug /debugtype:pdata /pdb:%t.pdb /dll /out:%t.dll /entry:main /nodefaultlib \
# RUN: %t1.obj %t2.obj
# RUN: llvm-pdbutil pdb2yaml -pdb-stream %t.pdb | FileCheck %s
# CHECK: PdbStream:
-# CHECK-NEXT: Age: 0
+# CHECK-NEXT: Age: 1
# CHECK-NEXT: Guid:
# CHECK-NEXT: Signature:
# CHECK-NEXT: Features: [ VC140 ]
Index: lld/trunk/test/COFF/pdb-source-lines.test
===================================================================
--- lld/trunk/test/COFF/pdb-source-lines.test
+++ lld/trunk/test/COFF/pdb-source-lines.test
@@ -19,10 +19,11 @@
RUN: yaml2obj %S/Inputs/pdb_lines_1.yaml -o %t.pdb_lines_1.obj
RUN: yaml2obj %S/Inputs/pdb_lines_2.yaml -o %t.pdb_lines_2.obj
+RUN: rm -f %t.exe %t.pdb
RUN: lld-link -debug -entry:main -nodefaultlib -out:%t.exe -pdb:%t.pdb %t.pdb_lines_1.obj %t.pdb_lines_2.obj
RUN: llvm-pdbutil pdb2yaml -modules -module-files -subsections=lines,fc %t.pdb | FileCheck %s
-CHECK-LABEL: DbiStream:
+CHECK-LABEL: DbiStream:
CHECK-NEXT: VerHeader: V70
CHECK-NEXT: Age: 1
CHECK-NEXT: BuildNumber: 0
@@ -30,22 +31,22 @@
CHECK-NEXT: PdbDllRbld: 0
CHECK-NEXT: Flags: 0
CHECK-NEXT: MachineType: x86
-CHECK-NEXT: Modules:
+CHECK-NEXT: Modules:
CHECK-LABEL: - Module: {{.*}}pdb_lines_1.obj
CHECK-NEXT: ObjFile: {{.*}}pdb_lines_1.obj
-CHECK-NEXT: SourceFiles:
+CHECK-NEXT: SourceFiles:
CHECK-NEXT: - '{{.*}}pdb_lines_1.c'
CHECK-NEXT: - '{{.*}}foo.h'
-CHECK-NEXT: Subsections:
+CHECK-NEXT: Subsections:
CHECK-NEXT: - !Lines
CHECK-NEXT: CodeSize: 19
CHECK-NEXT: Flags: [ ]
CHECK-NEXT: RelocOffset: 0
CHECK-NEXT: RelocSegment: 2
-CHECK-NEXT: Blocks:
+CHECK-NEXT: Blocks:
CHECK-NEXT: - FileName: '{{.*}}pdb_lines_1.c'
-CHECK-NEXT: Lines:
+CHECK-NEXT: Lines:
CHECK-NEXT: - Offset: 0
CHECK-NEXT: LineStart: 2
CHECK-NEXT: IsStatement: true
@@ -62,9 +63,9 @@
CHECK-NEXT: LineStart: 5
CHECK-NEXT: IsStatement: true
CHECK-NEXT: EndDelta: 0
-CHECK-NEXT: Columns:
+CHECK-NEXT: Columns:
CHECK-NEXT: - !FileChecksums
-CHECK-NEXT: Checksums:
+CHECK-NEXT: Checksums:
CHECK-NEXT: - FileName: '{{.*}}pdb_lines_1.c'
CHECK-NEXT: Kind: MD5
CHECK-NEXT: Checksum: 4EB19DCD86C3BA2238A255C718572E7B
@@ -76,9 +77,9 @@
CHECK-NEXT: Flags: [ ]
CHECK-NEXT: RelocOffset: 32
CHECK-NEXT: RelocSegment: 2
-CHECK-NEXT: Blocks:
+CHECK-NEXT: Blocks:
CHECK-NEXT: - FileName: '{{.*}}foo.h'
-CHECK-NEXT: Lines:
+CHECK-NEXT: Lines:
CHECK-NEXT: - Offset: 0
CHECK-NEXT: LineStart: 2
CHECK-NEXT: IsStatement: true
@@ -91,21 +92,21 @@
CHECK-NEXT: LineStart: 4
CHECK-NEXT: IsStatement: true
CHECK-NEXT: EndDelta: 0
-CHECK-NEXT: Columns:
+CHECK-NEXT: Columns:
CHECK-LABEL: - Module: {{.*}}pdb_lines_2.obj
CHECK-NEXT: ObjFile: {{.*}}pdb_lines_2.obj
-CHECK-NEXT: SourceFiles:
+CHECK-NEXT: SourceFiles:
CHECK-NEXT: - '{{.*}}pdb_lines_2.c'
-CHECK-NEXT: Subsections:
+CHECK-NEXT: Subsections:
CHECK-NEXT: - !Lines
CHECK-NEXT: CodeSize: 1
CHECK-NEXT: Flags: [ ]
CHECK-NEXT: RelocOffset: 48
CHECK-NEXT: RelocSegment: 2
-CHECK-NEXT: Blocks:
+CHECK-NEXT: Blocks:
CHECK-NEXT: - FileName: '{{.*}}pdb_lines_2.c'
-CHECK-NEXT: Lines:
+CHECK-NEXT: Lines:
CHECK-NEXT: - Offset: 0
CHECK-NEXT: LineStart: 1
CHECK-NEXT: IsStatement: true
@@ -114,9 +115,9 @@
CHECK-NEXT: LineStart: 2
CHECK-NEXT: IsStatement: true
CHECK-NEXT: EndDelta: 0
-CHECK-NEXT: Columns:
+CHECK-NEXT: Columns:
CHECK-NEXT: - !FileChecksums
-CHECK-NEXT: Checksums:
+CHECK-NEXT: Checksums:
CHECK-NEXT: - FileName: '{{.*}}pdb_lines_2.c'
CHECK-NEXT: Kind: MD5
CHECK-NEXT: Checksum: DF91CB3A2B8D917486574BB50CAC4CC7
Index: lld/trunk/test/COFF/pdb.test
===================================================================
--- lld/trunk/test/COFF/pdb.test
+++ lld/trunk/test/COFF/pdb.test
@@ -1,5 +1,6 @@
# RUN: yaml2obj < %p/Inputs/pdb1.yaml > %t1.obj
# RUN: yaml2obj < %p/Inputs/pdb2.yaml > %t2.obj
+# RUN: rm -f %t.dll %t.pdb
# RUN: lld-link /debug /pdb:%t.pdb /dll /out:%t.dll /entry:main /nodefaultlib \
# RUN: %t1.obj %t2.obj
Index: lld/trunk/test/COFF/rsds.test
===================================================================
--- lld/trunk/test/COFF/rsds.test
+++ lld/trunk/test/COFF/rsds.test
@@ -1,11 +1,20 @@
# RUN: yaml2obj %s > %t.obj
+# RUN: rm -f %t.dll %t.pdb
# RUN: lld-link /debug /dll /out:%t.dll /entry:DllMain %t.obj
-# RUN: llvm-readobj -coff-debug-directory %t.dll | FileCheck %s
+# RUN: llvm-readobj -coff-debug-directory %t.dll > %t.1.txt
+# RUN: lld-link /debug /dll /out:%t.dll /entry:DllMain %t.obj
+# RUN: llvm-readobj -coff-debug-directory %t.dll > %t.2.txt
+# RUN: cat %t.1.txt %t.2.txt | FileCheck %s
+# RUN: rm -f %t.dll %t.pdb
+# RUN: lld-link /debug /pdb:%t.pdb /dll /out:%t.dll /entry:DllMain %t.obj
+# RUN: llvm-readobj -coff-debug-directory %t.dll > %t.3.txt
# RUN: lld-link /debug /pdb:%t.pdb /dll /out:%t.dll /entry:DllMain %t.obj
-# RUN: llvm-readobj -coff-debug-directory %t.dll | FileCheck %s
+# RUN: llvm-readobj -coff-debug-directory %t.dll > %t.4.txt
+# RUN: cat %t.3.txt %t.4.txt | FileCheck %s
+# CHECK: File: [[FILE:.*]].dll
# CHECK: DebugDirectory [
# CHECK: DebugEntry {
# CHECK: Characteristics: 0x0
@@ -18,12 +27,31 @@
# CHECK: PointerToRawData: 0x{{[^0]}}
# CHECK: PDBInfo {
# CHECK: PDBSignature: 0x53445352
-# CHECK: PDBGUID:
+# CHECK: PDBGUID: [[GUID:\(([A-Za-z0-9]{2} ?){16}\)]]
# CHECK: PDBAge: 1
# CHECK: PDBFileName: {{.*}}.pdb
# CHECK: }
# CHECK: }
# CHECK: ]
+# CHECK: File: [[FILE]].dll
+# CHECK: DebugDirectory [
+# CHECK: DebugEntry {
+# CHECK: Characteristics: 0x0
+# CHECK: TimeDateStamp: 1970-01-01 00:00:00 (0x0)
+# CHECK: MajorVersion: 0x0
+# CHECK: MinorVersion: 0x0
+# CHECK: Type: CodeView (0x2)
+# CHECK: SizeOfData: 0x{{[^0]}}
+# CHECK: AddressOfRawData: 0x{{[^0]}}
+# CHECK: PointerToRawData: 0x{{[^0]}}
+# CHECK: PDBInfo {
+# CHECK: PDBSignature: 0x53445352
+# CHECK: PDBGUID: [[GUID]]
+# CHECK: PDBAge: 2
+# CHECK: PDBFileName: {{.*}}.pdb
+# CHECK: }
+# CHECK: }
+# CHECK: ]
--- !COFF
header: