Index: test/tools/llvm-objcopy/COFF/strip-unneeded.test =================================================================== --- test/tools/llvm-objcopy/COFF/strip-unneeded.test +++ test/tools/llvm-objcopy/COFF/strip-unneeded.test @@ -5,6 +5,13 @@ RUN: llvm-objcopy --strip-unneeded %t.in.o %t.out.o RUN: llvm-objdump -t %t.out.o | FileCheck %s --check-prefix=SYMBOLS +RUN: llvm-objcopy --strip-unneeded-symbol=external_undefined_unreferenced \ +RUN: --strip-unneeded-symbol=local_unreferenced \ +RUN: --strip-unneeded-symbol=local_undefined_unreferenced \ +RUN: --strip-unneeded-symbol='@feat.00' \ +RUN: %t.in.o %t.out2.o +RUN: cmp %t.out.o %t.out2.o + SYMBOLS: SYMBOL TABLE: SYMBOLS-NEXT: external SYMBOLS-NEXT: external_undefined Index: test/tools/llvm-objcopy/ELF/strip-unneeded.test =================================================================== --- test/tools/llvm-objcopy/ELF/strip-unneeded.test +++ test/tools/llvm-objcopy/ELF/strip-unneeded.test @@ -5,6 +5,29 @@ # RUN: cmp %t %t1 # RUN: llvm-readobj --symbols %t2 | FileCheck %s +# RUN: llvm-objcopy --strip-unneeded-symbol=bar \ +# RUN: --strip-unneeded-symbol=foobar \ +# RUN: --strip-unneeded-symbol=foobaz \ +# RUN: --strip-unneeded-symbol=foo \ +# RUN: --strip-unneeded-symbol=fileSymbol \ +# RUN: --strip-unneeded-symbol=sectionSymbol \ +# RUN: %t %t3 +# RUN: cmp %t2 %t3 + +# RUN: llvm-objcopy --regex --strip-unneeded-symbol='.*' %t %t4 +# RUN: cmp %t2 %t4 + +# RUN: echo " bar # bar " > %t.list.txt +# RUN: echo "foobar" >> %t.list.txt +# RUN: echo "foobaz" >> %t.list.txt +# RUN: echo " # comment " >> %t.list.txt +# RUN: llvm-objcopy --strip-unneeded-symbols %t.list.txt %t %t5 +# RUN: cmp %t2 %t5 + +# RUN: echo " .* # * - remove all " > %t.list2.txt +# RUN: llvm-objcopy --regex --strip-unneeded-symbols %t.list2.txt %t %t6 +# RUN: cmp %t2 %t6 + # Verify that llvm-strip modifies the symbol table the same way. # RUN: llvm-strip --strip-unneeded %t # RUN: cmp %t %t2 Index: tools/llvm-objcopy/COFF/COFFObjcopy.cpp =================================================================== --- tools/llvm-objcopy/COFF/COFFObjcopy.cpp +++ tools/llvm-objcopy/COFF/COFFObjcopy.cpp @@ -151,10 +151,13 @@ if (!Sym.Referenced) { // With --strip-unneeded, GNU objcopy removes all unreferenced local // symbols, and any unreferenced undefined external. - if (Config.StripUnneeded && - (Sym.Sym.StorageClass == IMAGE_SYM_CLASS_STATIC || - Sym.Sym.SectionNumber == 0)) - return true; + // With --strip-unneeded-symbol we strip only specific unreferenced + // local symbol instead of removing all of such. + if (Sym.Sym.StorageClass == IMAGE_SYM_CLASS_STATIC || + Sym.Sym.SectionNumber == 0) + if (Config.StripUnneeded || + is_contained(Config.UnneededSymbolsToRemove, Sym.Name)) + return true; // GNU objcopy keeps referenced local symbols and external symbols // if --discard-all is set, similar to what --strip-unneeded does, Index: tools/llvm-objcopy/CopyConfig.h =================================================================== --- tools/llvm-objcopy/CopyConfig.h +++ tools/llvm-objcopy/CopyConfig.h @@ -91,6 +91,7 @@ std::vector SymbolsToKeep; std::vector SymbolsToLocalize; std::vector SymbolsToRemove; + std::vector UnneededSymbolsToRemove; std::vector SymbolsToWeaken; std::vector ToRemove; std::vector SymbolsToKeepGlobal; Index: tools/llvm-objcopy/CopyConfig.cpp =================================================================== --- tools/llvm-objcopy/CopyConfig.cpp +++ tools/llvm-objcopy/CopyConfig.cpp @@ -468,6 +468,11 @@ for (auto Arg : InputArgs.filtered(OBJCOPY_strip_symbols)) addSymbolsFromFile(Config.SymbolsToRemove, DC.Alloc, Arg->getValue(), UseRegex); + for (auto Arg : InputArgs.filtered(OBJCOPY_strip_unneeded_symbol)) + Config.UnneededSymbolsToRemove.emplace_back(Arg->getValue(), UseRegex); + for (auto Arg : InputArgs.filtered(OBJCOPY_strip_unneeded_symbols)) + addSymbolsFromFile(Config.UnneededSymbolsToRemove, DC.Alloc, + Arg->getValue(), UseRegex); for (auto Arg : InputArgs.filtered(OBJCOPY_keep_symbol)) Config.SymbolsToKeep.emplace_back(Arg->getValue(), UseRegex); Index: tools/llvm-objcopy/ELF/ELFObjcopy.cpp =================================================================== --- tools/llvm-objcopy/ELF/ELFObjcopy.cpp +++ tools/llvm-objcopy/ELF/ELFObjcopy.cpp @@ -268,6 +268,12 @@ }; } +static bool isUnneededSymbol(const Symbol &Sym) { + return !Sym.Referenced && + (Sym.Binding == STB_LOCAL || Sym.getShndx() == SHN_UNDEF) && + Sym.Type != STT_FILE && Sym.Type != STT_SECTION; +} + // This function handles the high level operations of GNU objcopy including // handling command line options. It's important to outline certain properties // we expect to hold of the command line operations. Any operation that "keeps" @@ -336,7 +342,7 @@ // The purpose of this loop is to mark symbols referenced by sections // (like GroupSection or RelocationSection). This way, we know which // symbols are still 'needed' and which are not. - if (Config.StripUnneeded) { + if (Config.StripUnneeded || !Config.UnneededSymbolsToRemove.empty()) { for (auto &Section : Obj.sections()) Section.markSymbols(); } @@ -359,10 +365,10 @@ if (is_contained(Config.SymbolsToRemove, Sym.Name)) return true; - if (Config.StripUnneeded && !Sym.Referenced && - (Sym.Binding == STB_LOCAL || Sym.getShndx() == SHN_UNDEF) && - Sym.Type != STT_FILE && Sym.Type != STT_SECTION) - return true; + if (isUnneededSymbol(Sym)) + if (Config.StripUnneeded || + is_contained(Config.UnneededSymbolsToRemove, Sym.Name)) + return true; return false; }; Index: tools/llvm-objcopy/ObjcopyOpts.td =================================================================== --- tools/llvm-objcopy/ObjcopyOpts.td +++ tools/llvm-objcopy/ObjcopyOpts.td @@ -122,6 +122,15 @@ HelpText<"Remove all non-allocated sections">; def strip_unneeded : Flag<["-", "--"], "strip-unneeded">, HelpText<"Remove all symbols not needed by relocations">; +defm strip_unneeded_symbol + : Eq<"strip-unneeded-symbol", + "Remove symbol if it is not needed by relocations">, + MetaVarName<"symbol">; +defm strip_unneeded_symbols + : Eq<"strip-unneeded-symbols", + "Reads a list of symbols from and removes them " + "if they are not needed by relocations">, + MetaVarName<"filename">; def extract_dwo : Flag<["-", "--"], "extract-dwo">,