[llvm] r323477 - [llvm-objcopy] Add --add-gnu-debuglink
Jake Ehrlich via llvm-commits
llvm-commits at lists.llvm.org
Thu Jan 25 14:15:15 PST 2018
Author: jakehehrlich
Date: Thu Jan 25 14:15:14 2018
New Revision: 323477
URL: http://llvm.org/viewvc/llvm-project?rev=323477&view=rev
Log:
[llvm-objcopy] Add --add-gnu-debuglink
This change adds support for --add-gnu-debuglink to llvm-objcopy
Differential Revision: https://reviews.llvm.org/D41731
Added:
llvm/trunk/test/tools/llvm-objcopy/add-gnu-debuglink.test
Modified:
llvm/trunk/tools/llvm-objcopy/Object.cpp
llvm/trunk/tools/llvm-objcopy/Object.h
llvm/trunk/tools/llvm-objcopy/llvm-objcopy.cpp
Added: llvm/trunk/test/tools/llvm-objcopy/add-gnu-debuglink.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/tools/llvm-objcopy/add-gnu-debuglink.test?rev=323477&view=auto
==============================================================================
--- llvm/trunk/test/tools/llvm-objcopy/add-gnu-debuglink.test (added)
+++ llvm/trunk/test/tools/llvm-objcopy/add-gnu-debuglink.test Thu Jan 25 14:15:14 2018
@@ -0,0 +1,27 @@
+# RUN: yaml2obj %s > %t
+# RUN: printf 0000 > %t.blob
+# RUN: llvm-objcopy -add-gnu-debuglink=%t.blob %t %t2
+# RUN: llvm-readobj -sections -section-data %t2 | FileCheck %s
+
+!ELF
+FileHeader:
+ Class: ELFCLASS64
+ Data: ELFDATA2LSB
+ Type: ET_EXEC
+ Machine: EM_X86_64
+
+# CHECK: Name: .gnu_debuglink
+# CHECK-NEXT: Type: SHT_PROGBITS (0x1)
+# CHECK-NEXT: Flags [ (0x0)
+# CHECK-NEXT: ]
+# CHECK-NEXT: Address: 0x0
+# CHECK-NEXT: Offset:
+# CHECK-NEXT: Size: 32
+# CHECK-NEXT: Link: 0
+# CHECK-NEXT: Info: 0
+# CHECK-NEXT: AddressAlignment: 4
+# CHECK-NEXT: EntrySize: 0
+# CHECK-NEXT: SectionData (
+# CHECK-NEXT: 0000: 6164642D 676E752D 64656275 676C696E |add-gnu-debuglin|
+# CHECK-NEXT: 0010: 6B2E7465 73742E74 6D700000 72C49B0C |k.test.tmp..r...|
+# CHECK-NEXT: )
Modified: llvm/trunk/tools/llvm-objcopy/Object.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-objcopy/Object.cpp?rev=323477&r1=323476&r2=323477&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-objcopy/Object.cpp (original)
+++ llvm/trunk/tools/llvm-objcopy/Object.cpp Thu Jan 25 14:15:14 2018
@@ -18,6 +18,7 @@
#include "llvm/Object/ELFObjectFile.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/FileOutputBuffer.h"
+#include "llvm/Support/Path.h"
#include <algorithm>
#include <cstddef>
#include <cstdint>
@@ -343,6 +344,50 @@ void SectionWithStrTab::initialize(Secti
void SectionWithStrTab::finalize() { this->Link = StrTab->Index; }
+template <class ELFT>
+void GnuDebugLinkSection<ELFT>::init(StringRef File, StringRef Data) {
+ FileName = sys::path::stem(File);
+ // The format for the .gnu_debuglink starts with the stemmed file name and is
+ // followed by a null terminator and then the CRC32 of the file. The CRC32
+ // should be 4 byte aligned. So we add the FileName size, a 1 for the null
+ // byte, and then finally push the size to alignment and add 4.
+ Size = alignTo(FileName.size() + 1, 4) + 4;
+ // The CRC32 will only be aligned if we align the whole section.
+ Align = 4;
+ Type = ELF::SHT_PROGBITS;
+ Name = ".gnu_debuglink";
+ // For sections not found in segments, OriginalOffset is only used to
+ // establish the order that sections should go in. By using the maximum
+ // possible offset we cause this section to wind up at the end.
+ OriginalOffset = std::numeric_limits<uint64_t>::max();
+ JamCRC crc;
+ crc.update(ArrayRef<char>(Data.data(), Data.size()));
+ // The CRC32 value needs to be complemented because the JamCRC dosn't
+ // finalize the CRC32 value. It also dosn't negate the initial CRC32 value
+ // but it starts by default at 0xFFFFFFFF which is the complement of zero.
+ CRC32 = ~crc.getCRC();
+}
+
+template <class ELFT>
+GnuDebugLinkSection<ELFT>::GnuDebugLinkSection(StringRef File)
+ : FileName(File) {
+ // Read in the file to compute the CRC of it.
+ auto DebugOrErr = MemoryBuffer::getFile(File);
+ if (!DebugOrErr)
+ error("'" + File + "': " + DebugOrErr.getError().message());
+ auto Debug = std::move(*DebugOrErr);
+ init(File, Debug->getBuffer());
+}
+
+template <class ELFT>
+void GnuDebugLinkSection<ELFT>::writeSection(FileOutputBuffer &Out) const {
+ auto Buf = Out.getBufferStart() + Offset;
+ char *File = reinterpret_cast<char *>(Buf);
+ Elf_Word *CRC = reinterpret_cast<Elf_Word *>(Buf + Size - sizeof(Elf_Word));
+ *CRC = CRC32;
+ std::copy(std::begin(FileName), std::end(FileName), File);
+}
+
// Returns true IFF a section is wholly inside the range of a segment
static bool sectionWithinSegment(const SectionBase &Section,
const Segment &Segment) {
@@ -718,6 +763,10 @@ void Object<ELFT>::addSection(StringRef
Sections.push_back(std::move(Sec));
}
+template <class ELFT> void Object<ELFT>::addGnuDebugLink(StringRef File) {
+ Sections.emplace_back(llvm::make_unique<GnuDebugLinkSection<ELFT>>(File));
+}
+
template <class ELFT> void ELFObject<ELFT>::sortSections() {
// Put all sections in offset order. Maintain the ordering as closely as
// possible while meeting that demand however.
Modified: llvm/trunk/tools/llvm-objcopy/Object.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-objcopy/Object.h?rev=323477&r1=323476&r2=323477&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-objcopy/Object.h (original)
+++ llvm/trunk/tools/llvm-objcopy/Object.h Thu Jan 25 14:15:14 2018
@@ -16,6 +16,7 @@
#include "llvm/BinaryFormat/ELF.h"
#include "llvm/MC/StringTableBuilder.h"
#include "llvm/Object/ELFObjectFile.h"
+#include "llvm/Support/JamCRC.h"
#include <cstddef>
#include <cstdint>
#include <functional>
@@ -345,6 +346,24 @@ public:
}
};
+template <class ELFT> class GnuDebugLinkSection : public SectionBase {
+private:
+ // Elf_Word is 4-bytes on every format but has the same endianess as the elf
+ // type ELFT. We'll need to write the CRC32 out in the proper endianess so
+ // we'll make sure to use this type.
+ using Elf_Word = typename ELFT::Word;
+
+ StringRef FileName;
+ uint32_t CRC32;
+
+ void init(StringRef File, StringRef Data);
+
+public:
+ // If we add this section from an external source we can use this ctor.
+ GnuDebugLinkSection(StringRef File);
+ void writeSection(FileOutputBuffer &Out) const override;
+};
+
template <class ELFT> class Object {
private:
using SecPtr = std::unique_ptr<SectionBase>;
@@ -389,6 +408,7 @@ public:
const SectionBase *getSectionHeaderStrTab() const { return SectionNames; }
void removeSections(std::function<bool(const SectionBase &)> ToRemove);
void addSection(StringRef SecName, ArrayRef<uint8_t> Data);
+ void addGnuDebugLink(StringRef File);
virtual size_t totalSize() const = 0;
virtual void finalize() = 0;
virtual void write(FileOutputBuffer &Out) const = 0;
Modified: llvm/trunk/tools/llvm-objcopy/llvm-objcopy.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-objcopy/llvm-objcopy.cpp?rev=323477&r1=323476&r2=323477&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-objcopy/llvm-objcopy.cpp (original)
+++ llvm/trunk/tools/llvm-objcopy/llvm-objcopy.cpp Thu Jan 25 14:15:14 2018
@@ -121,6 +121,10 @@ static cl::opt<bool> LocalizeHidden(
"localize-hidden",
cl::desc(
"Mark all symbols that have hidden or internal visibility as local"));
+static cl::opt<std::string>
+ AddGnuDebugLink("add-gnu-debuglink",
+ cl::desc("adds a .gnu_debuglink for <debug-file>"),
+ cl::value_desc("debug-file"));
using SectionPred = std::function<bool(const SectionBase &Sec)>;
@@ -318,6 +322,10 @@ template <class ELFT> void CopyBinary(co
}
}
+ if (!AddGnuDebugLink.empty()) {
+ Obj->addGnuDebugLink(AddGnuDebugLink);
+ }
+
Obj->finalize();
WriteObjectFile(*Obj, OutputFilename.getValue());
}
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