[llvm] r309658 - [llvm][llvm-objcopy] Added support for outputting to binary in llvm-objcopy
Petr Hosek via llvm-commits
llvm-commits at lists.llvm.org
Mon Jul 31 22:18:31 PDT 2017
Author: phosek
Date: Mon Jul 31 22:18:30 2017
New Revision: 309658
URL: http://llvm.org/viewvc/llvm-project?rev=309658&view=rev
Log:
[llvm][llvm-objcopy] Added support for outputting to binary in llvm-objcopy
This change adds the "-O binary" flag which directs llvm-objcopy to
output the object file to the same format as GNU objcopy does when given
the flag "-O binary". This was done by splitting the Object class into
two subclasses ObjectELF and ObjectBianry which each output a different
format but relay on the same code to read in the Object in Object.
Patch by Jake Ehrlich
Differential Revision: https://reviews.llvm.org/D34480
Added:
llvm/trunk/test/tools/llvm-objcopy/basic-align-copy.test
llvm/trunk/test/tools/llvm-objcopy/basic-binary-copy.test
Modified:
llvm/trunk/tools/llvm-objcopy/LLVMBuild.txt
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/basic-align-copy.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/tools/llvm-objcopy/basic-align-copy.test?rev=309658&view=auto
==============================================================================
--- llvm/trunk/test/tools/llvm-objcopy/basic-align-copy.test (added)
+++ llvm/trunk/test/tools/llvm-objcopy/basic-align-copy.test Mon Jul 31 22:18:30 2017
@@ -0,0 +1,37 @@
+# RUN: yaml2obj %s -o %t
+# RUN: llvm-objcopy -O binary %t %t2
+# RUN: od -t x2 %t2 | FileCheck %s
+# RUN: wc -c < %t2 | FileCheck %s --check-prefix=SIZE
+
+!ELF
+FileHeader:
+ Class: ELFCLASS64
+ Data: ELFDATA2LSB
+ Type: ET_EXEC
+ Machine: EM_X86_64
+Sections:
+ - Name: .text
+ Type: SHT_PROGBITS
+ Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
+ AddressAlign: 0x0000000000001000
+ Content: "c3c3c3c3"
+ - Name: .data
+ Type: SHT_PROGBITS
+ Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
+ AddressAlign: 0x0000000000001000
+ Content: "32"
+ProgramHeaders:
+ - Type: PT_LOAD
+ Flags: [ PF_X, PF_R ]
+ Sections:
+ - Section: .text
+ - Type: PT_LOAD
+ Flags: [ PF_R ]
+ Sections:
+ - Section: .data
+
+# CHECK: 0000000 c3c3 c3c3 0000 0000 0000 0000 0000 0000
+# CHECK-NEXT: 0000020 0000 0000 0000 0000 0000 0000 0000 0000
+# CHECK-NEXT: *
+# CHECK-NEXT: 0010000 0032
+# SIZE: 4097
Added: llvm/trunk/test/tools/llvm-objcopy/basic-binary-copy.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/tools/llvm-objcopy/basic-binary-copy.test?rev=309658&view=auto
==============================================================================
--- llvm/trunk/test/tools/llvm-objcopy/basic-binary-copy.test (added)
+++ llvm/trunk/test/tools/llvm-objcopy/basic-binary-copy.test Mon Jul 31 22:18:30 2017
@@ -0,0 +1,25 @@
+# RUN: yaml2obj %s -o %t
+# RUN: llvm-objcopy -O binary %t %t2
+# RUN: od -t x2 -v %t2 | FileCheck %s
+# RUN: wc -c < %t2 | FileCheck %s --check-prefix=SIZE
+
+!ELF
+FileHeader:
+ Class: ELFCLASS64
+ Data: ELFDATA2LSB
+ Type: ET_EXEC
+ Machine: EM_X86_64
+Sections:
+ - Name: .text
+ Type: SHT_PROGBITS
+ Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
+ AddressAlign: 0x0000000000001000
+ Content: "c3c3c3c3"
+ProgramHeaders:
+ - Type: PT_LOAD
+ Flags: [ PF_X, PF_R ]
+ Sections:
+ - Section: .text
+
+# CHECK: 0000000 c3c3 c3c3
+# SIZE: 4
Modified: llvm/trunk/tools/llvm-objcopy/LLVMBuild.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-objcopy/LLVMBuild.txt?rev=309658&r1=309657&r2=309658&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-objcopy/LLVMBuild.txt (original)
+++ llvm/trunk/tools/llvm-objcopy/LLVMBuild.txt Mon Jul 31 22:18:30 2017
@@ -18,4 +18,4 @@
type = Tool
name = llvm-objcopy
parent = Tools
-required_libraries = Object MC
+required_libraries = Object Support MC
Modified: llvm/trunk/tools/llvm-objcopy/Object.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-objcopy/Object.cpp?rev=309658&r1=309657&r2=309658&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-objcopy/Object.cpp (original)
+++ llvm/trunk/tools/llvm-objcopy/Object.cpp Mon Jul 31 22:18:30 2017
@@ -42,6 +42,13 @@ void Segment::finalize() {
}
}
+void Segment::writeSegment(FileOutputBuffer &Out) const {
+ uint8_t *Buf = Out.getBufferStart() + Offset;
+ // We want to maintain segments' interstitial data and contents exactly.
+ // This lets us just copy segments directly.
+ std::copy(std::begin(Contents), std::end(Contents), Buf);
+}
+
void SectionBase::finalize() {}
template <class ELFT>
@@ -99,7 +106,8 @@ template <class ELFT>
void Object<ELFT>::readProgramHeaders(const ELFFile<ELFT> &ElfFile) {
uint32_t Index = 0;
for (const auto &Phdr : unwrapOrError(ElfFile.program_headers())) {
- Segments.emplace_back(llvm::make_unique<Segment>());
+ ArrayRef<uint8_t> Data{ElfFile.base() + Phdr.p_offset, Phdr.p_filesz};
+ Segments.emplace_back(llvm::make_unique<Segment>(Data));
Segment &Seg = *Segments.back();
Seg.Type = Phdr.p_type;
Seg.Flags = Phdr.p_flags;
@@ -135,7 +143,7 @@ Object<ELFT>::makeSection(const llvm::ob
default:
Data = unwrapOrError(ElfFile.getSectionContents(&Shdr));
return llvm::make_unique<Section>(Data);
- };
+ }
}
template <class ELFT>
@@ -163,12 +171,6 @@ void Object<ELFT>::readSectionHeaders(co
}
}
-template <class ELFT> size_t Object<ELFT>::totalSize() const {
- // We already have the section header offset so we can calculate the total
- // size by just adding up the size of each section header.
- return SHOffset + Sections.size() * sizeof(Elf_Shdr) + sizeof(Elf_Shdr);
-}
-
template <class ELFT> Object<ELFT>::Object(const ELFObjectFile<ELFT> &Obj) {
const auto &ElfFile = *Obj.getELFFile();
const auto &Ehdr = *ElfFile.getHeader();
@@ -187,22 +189,76 @@ template <class ELFT> Object<ELFT>::Obje
dyn_cast<StringTableSection>(Sections[Ehdr.e_shstrndx - 1].get());
}
-template <class ELFT> void Object<ELFT>::sortSections() {
+template <class ELFT>
+void Object<ELFT>::writeHeader(FileOutputBuffer &Out) const {
+ uint8_t *Buf = Out.getBufferStart();
+ Elf_Ehdr &Ehdr = *reinterpret_cast<Elf_Ehdr *>(Buf);
+ std::copy(Ident, Ident + 16, Ehdr.e_ident);
+ Ehdr.e_type = Type;
+ Ehdr.e_machine = Machine;
+ Ehdr.e_version = Version;
+ Ehdr.e_entry = Entry;
+ Ehdr.e_phoff = sizeof(Elf_Ehdr);
+ Ehdr.e_shoff = SHOffset;
+ Ehdr.e_flags = Flags;
+ Ehdr.e_ehsize = sizeof(Elf_Ehdr);
+ Ehdr.e_phentsize = sizeof(Elf_Phdr);
+ Ehdr.e_phnum = Segments.size();
+ Ehdr.e_shentsize = sizeof(Elf_Shdr);
+ Ehdr.e_shnum = Sections.size() + 1;
+ Ehdr.e_shstrndx = SectionNames->Index;
+}
+
+template <class ELFT>
+void Object<ELFT>::writeProgramHeaders(FileOutputBuffer &Out) const {
+ for (auto &Phdr : Segments)
+ Phdr->template writeHeader<ELFT>(Out);
+}
+
+template <class ELFT>
+void Object<ELFT>::writeSectionHeaders(FileOutputBuffer &Out) const {
+ uint8_t *Buf = Out.getBufferStart() + SHOffset;
+ // This reference serves to write the dummy section header at the begining
+ // of the file.
+ Elf_Shdr &Shdr = *reinterpret_cast<Elf_Shdr *>(Buf);
+ Shdr.sh_name = 0;
+ Shdr.sh_type = SHT_NULL;
+ Shdr.sh_flags = 0;
+ Shdr.sh_addr = 0;
+ Shdr.sh_offset = 0;
+ Shdr.sh_size = 0;
+ Shdr.sh_link = 0;
+ Shdr.sh_info = 0;
+ Shdr.sh_addralign = 0;
+ Shdr.sh_entsize = 0;
+
+ for (auto &Section : Sections)
+ Section->template writeHeader<ELFT>(Out);
+}
+
+template <class ELFT>
+void Object<ELFT>::writeSectionData(FileOutputBuffer &Out) const {
+ for (auto &Section : Sections)
+ Section->writeSection(Out);
+}
+
+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.
auto CompareSections = [](const SecPtr &A, const SecPtr &B) {
return A->OriginalOffset < B->OriginalOffset;
};
- std::stable_sort(std::begin(Sections), std::end(Sections), CompareSections);
+ std::stable_sort(std::begin(this->Sections), std::end(this->Sections),
+ CompareSections);
}
-template <class ELFT> void Object<ELFT>::assignOffsets() {
+template <class ELFT> void ELFObject<ELFT>::assignOffsets() {
// Decide file offsets and indexes.
- size_t PhdrSize = Segments.size() * sizeof(Elf_Phdr);
+ size_t PhdrSize = this->Segments.size() * sizeof(Elf_Phdr);
// We can put section data after the ELF header and the program headers.
uint64_t Offset = sizeof(Elf_Ehdr) + PhdrSize;
uint64_t Index = 1;
- for (auto &Section : Sections) {
+ for (auto &Section : this->Sections) {
// The segment can have a different alignment than the section. In the case
// that there is a parent segment then as long as we satisfy the alignment
// of the segment it should follow that that the section is aligned.
@@ -249,93 +305,88 @@ template <class ELFT> void Object<ELFT>:
// this needs to be 4-byte aligned and on 64-bit it needs to be 8-byte aligned
// so the size of ELFT::Addr is used to ensure this.
Offset = alignTo(Offset, sizeof(typename ELFT::Addr));
- SHOffset = Offset;
+ this->SHOffset = Offset;
}
-template <class ELFT> void Object<ELFT>::finalize() {
- for (auto &Section : Sections)
- SectionNames->addString(Section->Name);
+template <class ELFT> size_t ELFObject<ELFT>::totalSize() const {
+ // We already have the section header offset so we can calculate the total
+ // size by just adding up the size of each section header.
+ return this->SHOffset + this->Sections.size() * sizeof(Elf_Shdr) +
+ sizeof(Elf_Shdr);
+}
+
+template <class ELFT> void ELFObject<ELFT>::write(FileOutputBuffer &Out) const {
+ this->writeHeader(Out);
+ this->writeProgramHeaders(Out);
+ this->writeSectionData(Out);
+ this->writeSectionHeaders(Out);
+}
+
+template <class ELFT> void ELFObject<ELFT>::finalize() {
+ for (const auto &Section : this->Sections) {
+ this->SectionNames->addString(Section->Name);
+ }
sortSections();
assignOffsets();
// Finalize SectionNames first so that we can assign name indexes.
- SectionNames->finalize();
+ this->SectionNames->finalize();
// Finally now that all offsets and indexes have been set we can finalize any
// remaining issues.
- uint64_t Offset = SHOffset + sizeof(Elf_Shdr);
- for (auto &Section : Sections) {
+ uint64_t Offset = this->SHOffset + sizeof(Elf_Shdr);
+ for (auto &Section : this->Sections) {
Section->HeaderOffset = Offset;
Offset += sizeof(Elf_Shdr);
- Section->NameIndex = SectionNames->findIndex(Section->Name);
+ Section->NameIndex = this->SectionNames->findIndex(Section->Name);
Section->finalize();
}
- for (auto &Segment : Segments)
+ for (auto &Segment : this->Segments)
Segment->finalize();
}
-template <class ELFT>
-void Object<ELFT>::writeHeader(FileOutputBuffer &Out) const {
- uint8_t *Buf = Out.getBufferStart();
- Elf_Ehdr &Ehdr = *reinterpret_cast<Elf_Ehdr *>(Buf);
- std::copy(Ident, Ident + 16, Ehdr.e_ident);
- Ehdr.e_type = Type;
- Ehdr.e_machine = Machine;
- Ehdr.e_version = Version;
- Ehdr.e_entry = Entry;
- Ehdr.e_phoff = sizeof(Elf_Ehdr);
- Ehdr.e_shoff = SHOffset;
- Ehdr.e_flags = Flags;
- Ehdr.e_ehsize = sizeof(Elf_Ehdr);
- Ehdr.e_phentsize = sizeof(Elf_Phdr);
- Ehdr.e_phnum = Segments.size();
- Ehdr.e_shentsize = sizeof(Elf_Shdr);
- Ehdr.e_shnum = Sections.size() + 1;
- Ehdr.e_shstrndx = SectionNames->Index;
+template <class ELFT> size_t BinaryObject<ELFT>::totalSize() const {
+ return TotalSize;
}
template <class ELFT>
-void Object<ELFT>::writeProgramHeaders(FileOutputBuffer &Out) const {
- for (auto &Phdr : Segments)
- Phdr->template writeHeader<ELFT>(Out);
+void BinaryObject<ELFT>::write(FileOutputBuffer &Out) const {
+ for (auto &Segment : this->Segments) {
+ if (Segment->Type == llvm::ELF::PT_LOAD) {
+ Segment->writeSegment(Out);
+ }
+ }
}
-template <class ELFT>
-void Object<ELFT>::writeSectionHeaders(FileOutputBuffer &Out) const {
- uint8_t *Buf = Out.getBufferStart() + SHOffset;
- // This reference serves to write the dummy section header at the begining
- // of the file.
- Elf_Shdr &Shdr = *reinterpret_cast<Elf_Shdr *>(Buf);
- Shdr.sh_name = 0;
- Shdr.sh_type = SHT_NULL;
- Shdr.sh_flags = 0;
- Shdr.sh_addr = 0;
- Shdr.sh_offset = 0;
- Shdr.sh_size = 0;
- Shdr.sh_link = 0;
- Shdr.sh_info = 0;
- Shdr.sh_addralign = 0;
- Shdr.sh_entsize = 0;
-
- for (auto &Section : Sections)
- Section->template writeHeader<ELFT>(Out);
-}
+template <class ELFT> void BinaryObject<ELFT>::finalize() {
+ for (auto &Segment : this->Segments)
+ Segment->finalize();
-template <class ELFT>
-void Object<ELFT>::writeSectionData(FileOutputBuffer &Out) const {
- for (auto &Section : Sections)
- Section->writeSection(Out);
-}
+ // Put all segments in offset order.
+ auto CompareSegments = [](const SegPtr &A, const SegPtr &B) {
+ return A->Offset < B->Offset;
+ };
+ std::sort(std::begin(this->Segments), std::end(this->Segments),
+ CompareSegments);
-template <class ELFT> void Object<ELFT>::write(FileOutputBuffer &Out) {
- writeHeader(Out);
- writeProgramHeaders(Out);
- writeSectionData(Out);
- writeSectionHeaders(Out);
+ uint64_t Offset = 0;
+ for (auto &Segment : this->Segments) {
+ if (Segment->Type == llvm::ELF::PT_LOAD) {
+ Offset = alignTo(Offset, Segment->Align);
+ Segment->Offset = Offset;
+ Offset += Segment->FileSize;
+ }
+ }
+ TotalSize = Offset;
}
-template class Object<ELF64LE>;
-template class Object<ELF64BE>;
-template class Object<ELF32LE>;
-template class Object<ELF32BE>;
+template class ELFObject<ELF64LE>;
+template class ELFObject<ELF64BE>;
+template class ELFObject<ELF32LE>;
+template class ELFObject<ELF32BE>;
+
+template class BinaryObject<ELF64LE>;
+template class BinaryObject<ELF64BE>;
+template class BinaryObject<ELF32LE>;
+template class BinaryObject<ELF32BE>;
Modified: llvm/trunk/tools/llvm-objcopy/Object.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-objcopy/Object.h?rev=309658&r1=309657&r2=309658&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-objcopy/Object.h (original)
+++ llvm/trunk/tools/llvm-objcopy/Object.h Mon Jul 31 22:18:30 2017
@@ -58,6 +58,7 @@ private:
};
std::set<const SectionBase *, SectionCompare> Sections;
+ llvm::ArrayRef<uint8_t> Contents;
public:
uint64_t Align;
@@ -70,6 +71,7 @@ public:
uint64_t Type;
uint64_t VAddr;
+ Segment(llvm::ArrayRef<uint8_t> Data) : Contents(Data) {}
void finalize();
const SectionBase *firstSection() const {
if (!Sections.empty())
@@ -78,6 +80,7 @@ public:
}
void addSection(const SectionBase *sec) { Sections.insert(sec); }
template <class ELFT> void writeHeader(llvm::FileOutputBuffer &Out) const;
+ void writeSegment(llvm::FileOutputBuffer &Out) const;
};
class Section : public SectionBase {
@@ -117,16 +120,16 @@ private:
typedef typename ELFT::Ehdr Elf_Ehdr;
typedef typename ELFT::Phdr Elf_Phdr;
- StringTableSection *SectionNames;
- std::vector<SecPtr> Sections;
- std::vector<SegPtr> Segments;
-
- void sortSections();
- void assignOffsets();
SecPtr makeSection(const llvm::object::ELFFile<ELFT> &ElfFile,
const Elf_Shdr &Shdr);
void readProgramHeaders(const llvm::object::ELFFile<ELFT> &ElfFile);
void readSectionHeaders(const llvm::object::ELFFile<ELFT> &ElfFile);
+
+protected:
+ StringTableSection *SectionNames;
+ std::vector<SecPtr> Sections;
+ std::vector<SegPtr> Segments;
+
void writeHeader(llvm::FileOutputBuffer &Out) const;
void writeProgramHeaders(llvm::FileOutputBuffer &Out) const;
void writeSectionData(llvm::FileOutputBuffer &Out) const;
@@ -142,9 +145,43 @@ public:
uint32_t Flags;
Object(const llvm::object::ELFObjectFile<ELFT> &Obj);
- size_t totalSize() const;
- void finalize();
- void write(llvm::FileOutputBuffer &Out);
+ virtual size_t totalSize() const = 0;
+ virtual void finalize() = 0;
+ virtual void write(llvm::FileOutputBuffer &Out) const = 0;
+ virtual ~Object() = default;
+};
+
+template <class ELFT> class ELFObject : public Object<ELFT> {
+private:
+ typedef std::unique_ptr<SectionBase> SecPtr;
+ typedef std::unique_ptr<Segment> SegPtr;
+
+ typedef typename ELFT::Shdr Elf_Shdr;
+ typedef typename ELFT::Ehdr Elf_Ehdr;
+ typedef typename ELFT::Phdr Elf_Phdr;
+
+ void sortSections();
+ void assignOffsets();
+
+public:
+ ELFObject(const llvm::object::ELFObjectFile<ELFT> &Obj) : Object<ELFT>(Obj) {}
+ void finalize() override;
+ size_t totalSize() const override;
+ void write(llvm::FileOutputBuffer &Out) const override;
};
+template <class ELFT> class BinaryObject : public Object<ELFT> {
+private:
+ typedef std::unique_ptr<SectionBase> SecPtr;
+ typedef std::unique_ptr<Segment> SegPtr;
+
+ uint64_t TotalSize;
+
+public:
+ BinaryObject(const llvm::object::ELFObjectFile<ELFT> &Obj)
+ : Object<ELFT>(Obj) {}
+ void finalize() override;
+ size_t totalSize() const override;
+ void write(llvm::FileOutputBuffer &Out) const override;
+};
#endif
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=309658&r1=309657&r2=309658&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-objcopy/llvm-objcopy.cpp (original)
+++ llvm/trunk/tools/llvm-objcopy/llvm-objcopy.cpp Mon Jul 31 22:18:30 2017
@@ -53,13 +53,23 @@ LLVM_ATTRIBUTE_NORETURN void reportError
cl::opt<std::string> InputFilename(cl::Positional, cl::desc("<input>"));
cl::opt<std::string> OutputFilename(cl::Positional, cl::desc("<output>"),
cl::init("-"));
+cl::opt<std::string>
+ OutputFormat("O", cl::desc("set output format to one of the following:"
+ "\n\tbinary"));
void CopyBinary(const ELFObjectFile<ELF64LE> &ObjFile) {
std::unique_ptr<FileOutputBuffer> Buffer;
- Object<ELF64LE> Obj{ObjFile};
- Obj.finalize();
+ std::unique_ptr<Object<ELF64LE>> Obj;
+ if (!OutputFormat.empty() && OutputFormat != "binary")
+ error("invalid output format '" + OutputFormat + "'");
+
+ if (!OutputFormat.empty() && OutputFormat == "binary")
+ Obj = llvm::make_unique<BinaryObject<ELF64LE>>(ObjFile);
+ else
+ Obj = llvm::make_unique<ELFObject<ELF64LE>>(ObjFile);
+ Obj->finalize();
ErrorOr<std::unique_ptr<FileOutputBuffer>> BufferOrErr =
- FileOutputBuffer::create(OutputFilename, Obj.totalSize(),
+ FileOutputBuffer::create(OutputFilename, Obj->totalSize(),
FileOutputBuffer::F_executable);
if (BufferOrErr.getError())
error("failed to open " + OutputFilename);
@@ -68,7 +78,7 @@ void CopyBinary(const ELFObjectFile<ELF6
std::error_code EC;
if (EC)
report_fatal_error(EC.message());
- Obj.write(*Buffer);
+ Obj->write(*Buffer);
if (auto EC = Buffer->commit())
reportError(OutputFilename, EC);
}
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