diff --git a/llvm/docs/CommandGuide/llvm-objcopy.rst b/llvm/docs/CommandGuide/llvm-objcopy.rst --- a/llvm/docs/CommandGuide/llvm-objcopy.rst +++ b/llvm/docs/CommandGuide/llvm-objcopy.rst @@ -72,6 +72,9 @@ Remove all sections from the output, except for sections named ``
``. Can be specified multiple times to keep multiple sections. + For MachO objects, ``
`` must be formatted as + ``,
``. + .. option:: --regex If specified, symbol and section names specified by other switches are treated diff --git a/llvm/test/tools/llvm-objcopy/MachO/only-section.test b/llvm/test/tools/llvm-objcopy/MachO/only-section.test new file mode 100644 --- /dev/null +++ b/llvm/test/tools/llvm-objcopy/MachO/only-section.test @@ -0,0 +1,153 @@ +## Show that if --only-section is given, llvm-objcopy removes all sections +## except ones specified in the option. + +# RUN: yaml2obj %s > %t + +## Specify all sections. The output file should be the same as the input. +# RUN: llvm-objcopy -j __TEXT,__text -j __DATA,__data -j __TEXT,__const %t %t2 +# RUN: cmp %t %t2 + +## Specify one section. The output file should contain only that section. +# RUN: llvm-objcopy --only-section __TEXT,__text %t %t3 +# RUN: llvm-readobj --sections --section-data --macho-segment %t3 \ +# RUN: | FileCheck %s --check-prefix=ONLY-TEXT-SECTION + +# ONLY-TEXT-SECTION: Sections [ +# ONLY-TEXT-SECTION-NEXT: Section { +# ONLY-TEXT-SECTION-NEXT: Index: 0 +# ONLY-TEXT-SECTION-NEXT: Name: __text (5F 5F 74 65 78 74 00 00 00 00 00 00 00 00 00 00) +# ONLY-TEXT-SECTION-NEXT: Segment: __TEXT (5F 5F 54 45 58 54 00 00 00 00 00 00 00 00 00 00) +# ONLY-TEXT-SECTION-NEXT: Address: 0x0 +# ONLY-TEXT-SECTION-NEXT: Size: 0x4 +# ONLY-TEXT-SECTION-NEXT: Offset: 184 +# ONLY-TEXT-SECTION-NEXT: Alignment: 0 +# ONLY-TEXT-SECTION-NEXT: RelocationOffset: 0x0 +# ONLY-TEXT-SECTION-NEXT: RelocationCount: 0 +# ONLY-TEXT-SECTION-NEXT: Type: Regular (0x0) +# ONLY-TEXT-SECTION-NEXT: Attributes [ (0x800004) +# ONLY-TEXT-SECTION-NEXT: PureInstructions (0x800000) +# ONLY-TEXT-SECTION-NEXT: SomeInstructions (0x4) +# ONLY-TEXT-SECTION-NEXT: ] +# ONLY-TEXT-SECTION-NEXT: Reserved1: 0x0 +# ONLY-TEXT-SECTION-NEXT: Reserved2: 0x0 +# ONLY-TEXT-SECTION-NEXT: Reserved3: 0x0 +# ONLY-TEXT-SECTION-NEXT: SectionData ( +# ONLY-TEXT-SECTION-NEXT: 0000: AABBCCDD |....| +# ONLY-TEXT-SECTION-NEXT: ) +# ONLY-TEXT-SECTION-NEXT: } +# ONLY-TEXT-SECTION-NEXT: ] +# ONLY-TEXT-SECTION-NEXT: Segment { +# ONLY-TEXT-SECTION-NEXT: Cmd: LC_SEGMENT_64 +# ONLY-TEXT-SECTION-NEXT: Name: +# ONLY-TEXT-SECTION-NEXT: Size: 152 +# ONLY-TEXT-SECTION-NEXT: vmaddr: 0x0 +# ONLY-TEXT-SECTION-NEXT: vmsize: 0x4 +# ONLY-TEXT-SECTION-NEXT: fileoff: 184 +# ONLY-TEXT-SECTION-NEXT: filesize: 4 +# ONLY-TEXT-SECTION-NEXT: maxprot: rwx +# ONLY-TEXT-SECTION-NEXT: initprot: rwx +# ONLY-TEXT-SECTION-NEXT: nsects: 1 +# ONLY-TEXT-SECTION-NEXT: flags: 0x0 +# ONLY-TEXT-SECTION-NEXT: } + +## Remove all sections if the specified section name is not present in the input. +# RUN: llvm-objcopy --only-section __TEXT,__nonexistent %t %t4 2>&1 +# RUN: llvm-readobj --sections --section-data --macho-segment %t4 \ +# RUN: | FileCheck %s --check-prefix=NONEXISTENT-SECTION + +# NONEXISTENT-SECTION: Sections [ +# NONEXISTENT-SECTION-NEXT: ] +# NONEXISTENT-SECTION-NEXT: Segment { +# NONEXISTENT-SECTION-NEXT: Cmd: LC_SEGMENT_64 +# NONEXISTENT-SECTION-NEXT: Name: +# NONEXISTENT-SECTION-NEXT: Size: 72 +# NONEXISTENT-SECTION-NEXT: vmaddr: 0x0 +# NONEXISTENT-SECTION-NEXT: vmsize: 0x0 +# NONEXISTENT-SECTION-NEXT: fileoff: 104 +# NONEXISTENT-SECTION-NEXT: filesize: 0 +# NONEXISTENT-SECTION-NEXT: maxprot: rwx +# NONEXISTENT-SECTION-NEXT: initprot: rwx +# NONEXISTENT-SECTION-NEXT: nsects: 0 +# NONEXISTENT-SECTION-NEXT: flags: 0x0 +# NONEXISTENT-SECTION-NEXT: } + +## Use wildcard to specify all sections under the __TEXT segment. +# RUN: llvm-objcopy --only-section "__TEXT,*" %t %t5 2>&1 +# RUN: llvm-readobj --file-header --sections %t5 \ +# RUN: | FileCheck %s --check-prefix=WILDCARD + +## Make sure that it doesn't care about the segment/section name separator ",". +# RUN: llvm-objcopy --only-section "__TEXT*" %t %t6 2>&1 +# RUN: cmp %t5 %t6 + +# WILDCARD: NumOfLoadCommands: 1 +# WILDCARD: Sections [ +# WILDCARD: Index: 0 +# WILDCARD-NEXT: Name: __text (5F 5F 74 65 78 74 00 00 00 00 00 00 00 00 00 00) +# WILDCARD: Index: 1 +# WILDCARD-NEXT: Name: __const (5F 5F 63 6F 6E 73 74 00 00 00 00 00 00 00 00 00) +# WILDCARD-NOT: Index: 2 +# WILDCARD: ] + +--- !mach-o +FileHeader: + magic: 0xFEEDFACF + cputype: 0x01000007 + cpusubtype: 0x00000003 + filetype: 0x00000001 + ncmds: 1 + sizeofcmds: 312 + flags: 0x00002000 + reserved: 0x00000000 +LoadCommands: + - cmd: LC_SEGMENT_64 + cmdsize: 312 + segname: '' + vmaddr: 0 + vmsize: 12 + fileoff: 344 + filesize: 12 + maxprot: 7 + initprot: 7 + nsects: 3 + flags: 0 + Sections: + - sectname: __text + segname: __TEXT + addr: 0x0000000000000000 + content: 'AABBCCDD' + size: 4 + offset: 344 + align: 0 + reloff: 0x00000000 + nreloc: 0 + flags: 0x80000400 + reserved1: 0x00000000 + reserved2: 0x00000000 + reserved3: 0x00000000 + - sectname: __data + segname: __DATA + addr: 0x0000000000000004 + content: 'DDAADDAA' + size: 4 + offset: 348 + align: 0 + reloff: 0x00000000 + nreloc: 0 + flags: 0x00000000 + reserved1: 0x00000000 + reserved2: 0x00000000 + reserved3: 0x00000000 + - sectname: __const + segname: __TEXT + addr: 0x0000000000000008 + content: 'EEFFEEFF' + size: 4 + offset: 352 + align: 0 + reloff: 0x00000000 + nreloc: 0 + flags: 0x00000000 + reserved1: 0x00000000 + reserved2: 0x00000000 + reserved3: 0x00000000 diff --git a/llvm/tools/llvm-objcopy/MachO/MachOObjcopy.cpp b/llvm/tools/llvm-objcopy/MachO/MachOObjcopy.cpp --- a/llvm/tools/llvm-objcopy/MachO/MachOObjcopy.cpp +++ b/llvm/tools/llvm-objcopy/MachO/MachOObjcopy.cpp @@ -18,6 +18,19 @@ namespace macho { using namespace object; +using SectionPred = std::function; + +static void removeSections(const CopyConfig &Config, Object &Obj) { + SectionPred RemovePred = [](const Section &) { return false; }; + + if (!Config.OnlySection.empty()) { + RemovePred = [&Config, RemovePred](const Section &Sec) { + return !Config.OnlySection.matches(Sec.CanonicalName); + }; + } + + return Obj.removeSections(RemovePred); +} static Error handleArgs(const CopyConfig &Config, Object &Obj) { if (Config.AllowBrokenLinks || !Config.BuildIdLinkDir.empty() || @@ -25,11 +38,10 @@ !Config.SplitDWO.empty() || !Config.SymbolsPrefix.empty() || !Config.AllocSectionsPrefix.empty() || !Config.AddSection.empty() || !Config.DumpSection.empty() || !Config.KeepSection.empty() || - Config.NewSymbolVisibility || !Config.OnlySection.empty() || - !Config.SymbolsToGlobalize.empty() || !Config.SymbolsToKeep.empty() || - !Config.SymbolsToLocalize.empty() || !Config.SymbolsToWeaken.empty() || - !Config.SymbolsToKeepGlobal.empty() || !Config.SectionsToRename.empty() || - !Config.SymbolsToRename.empty() || + Config.NewSymbolVisibility || !Config.SymbolsToGlobalize.empty() || + !Config.SymbolsToKeep.empty() || !Config.SymbolsToLocalize.empty() || + !Config.SymbolsToWeaken.empty() || !Config.SymbolsToKeepGlobal.empty() || + !Config.SectionsToRename.empty() || !Config.SymbolsToRename.empty() || !Config.UnneededSymbolsToRemove.empty() || !Config.SetSectionAlignment.empty() || !Config.SetSectionFlags.empty() || !Config.ToRemove.empty() || Config.ExtractDWO || Config.KeepFileSymbols || @@ -43,6 +55,7 @@ "option not supported by llvm-objcopy for MachO"); } + removeSections(Config, Obj); return Error::success(); } diff --git a/llvm/tools/llvm-objcopy/MachO/MachOReader.cpp b/llvm/tools/llvm-objcopy/MachO/MachOReader.cpp --- a/llvm/tools/llvm-objcopy/MachO/MachOReader.cpp +++ b/llvm/tools/llvm-objcopy/MachO/MachOReader.cpp @@ -35,6 +35,7 @@ .str(); S.Segname = StringRef(Sec.segname, strnlen(Sec.segname, sizeof(Sec.sectname))).str(); + S.CanonicalName = (Twine(S.Segname) + "," + S.Sectname).str(); S.Addr = Sec.addr; S.Size = Sec.size; S.Offset = Sec.offset; diff --git a/llvm/tools/llvm-objcopy/MachO/Object.h b/llvm/tools/llvm-objcopy/MachO/Object.h --- a/llvm/tools/llvm-objcopy/MachO/Object.h +++ b/llvm/tools/llvm-objcopy/MachO/Object.h @@ -38,6 +38,8 @@ struct Section { std::string Sectname; std::string Segname; + // CanonicalName is a string formatted as “,". + std::string CanonicalName; uint64_t Addr; uint64_t Size; uint32_t Offset; @@ -250,6 +252,8 @@ Optional DataInCodeCommandIndex; /// The index LC_FUNCTION_STARTS load comamnd if present. Optional FunctionStartsCommandIndex; + + void removeSections(function_ref ToRemove); }; } // end namespace macho diff --git a/llvm/tools/llvm-objcopy/MachO/Object.cpp b/llvm/tools/llvm-objcopy/MachO/Object.cpp --- a/llvm/tools/llvm-objcopy/MachO/Object.cpp +++ b/llvm/tools/llvm-objcopy/MachO/Object.cpp @@ -10,6 +10,13 @@ return Symbols[Index].get(); } +void Object::removeSections(function_ref ToRemove) { + for (LoadCommand &LC : LoadCommands) + LC.Sections.erase(std::remove_if(std::begin(LC.Sections), + std::end(LC.Sections), ToRemove), + std::end(LC.Sections)); +} + } // end namespace macho } // end namespace objcopy } // end namespace llvm