[llvm] r321884 - [llvm-objcopy] Add --localize-hidden option
Jake Ehrlich via llvm-commits
llvm-commits at lists.llvm.org
Fri Jan 5 11:19:09 PST 2018
Author: jakehehrlich
Date: Fri Jan 5 11:19:09 2018
New Revision: 321884
URL: http://llvm.org/viewvc/llvm-project?rev=321884&view=rev
Log:
[llvm-objcopy] Add --localize-hidden option
This change adds support in llvm-objcopy for GNU objcopy's --localize-hidden
option. This option changes every hidden or internal symbol into a local symbol.
Added:
llvm/trunk/test/tools/llvm-objcopy/localize-hidden.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/localize-hidden.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/tools/llvm-objcopy/localize-hidden.test?rev=321884&view=auto
==============================================================================
--- llvm/trunk/test/tools/llvm-objcopy/localize-hidden.test (added)
+++ llvm/trunk/test/tools/llvm-objcopy/localize-hidden.test Fri Jan 5 11:19:09 2018
@@ -0,0 +1,164 @@
+# RUN: yaml2obj %s > %t
+# RUN: llvm-objcopy -localize-hidden %t %t2
+# RUN: llvm-readobj -relocations -symbols %t2 | FileCheck %s
+
+!ELF
+FileHeader:
+ Class: ELFCLASS64
+ Data: ELFDATA2LSB
+ Type: ET_REL
+ Machine: EM_X86_64
+Sections:
+ - Name: .text
+ Type: SHT_PROGBITS
+ Flags: [ SHF_ALLOC, SHF_EXECINSTR ]
+ Address: 0x1000
+ AddressAlign: 0x0000000000000010
+ Size: 64
+ - Name: .data
+ Type: SHT_PROGBITS
+ Flags: [ SHF_ALLOC ]
+ Address: 0x2000
+ AddressAlign: 0x0000000000000010
+ Content: "0000000000000000"
+ - Name: .rel.text
+ Type: SHT_REL
+ Info: .text
+ Relocations:
+ - Offset: 0x1000
+ Symbol: undefGlobal
+ Type: R_X86_64_PC32
+Symbols:
+ Local:
+ - Name: hiddenLocal
+ Type: STT_FUNC
+ Section: .text
+ Value: 0x1008
+ Size: 8
+ Visibility: STV_HIDDEN
+ Weak:
+ - Name: hiddenWeak
+ Type: STT_FUNC
+ Section: .text
+ Value: 0x1010
+ Size: 8
+ Visibility: STV_HIDDEN
+ Global:
+ - Name: defaultGlobal
+ Type: STT_FUNC
+ Size: 8
+ Section: .text
+ Value: 0x1000
+ - Name: hiddenGlobal
+ Type: STT_OBJECT
+ Section: .data
+ Value: 0x2006
+ Size: 2
+ Visibility: STV_HIDDEN
+ - Name: undefGlobal
+ Type: STT_FUNC
+ Size: 8
+ - Name: internalGlobal
+ Type: STT_OBJECT
+ Section: .data
+ Value: 0x2002
+ Size: 2
+ Visibility: STV_INTERNAL
+ - Name: protectedGlobal
+ Type: STT_OBJECT
+ Section: .data
+ Value: 0x2000
+ Size: 4
+ Visibility: STV_PROTECTED
+
+#CHECK: Relocations [
+#CHECK-NEXT: Section (3) .rel.text {
+#CHECK-NEXT: 0x1000 R_X86_64_PC32 undefGlobal 0x0
+#CHECK-NEXT: }
+#CHECK-NEXT:]
+
+
+#CHECK: Symbols [
+#CHECK-NEXT: Symbol {
+#CHECK-NEXT: Name:
+#CHECK-NEXT: Value: 0x0
+#CHECK-NEXT: Size: 0
+#CHECK-NEXT: Binding: Local
+#CHECK-NEXT: Type: None
+#CHECK-NEXT: Other: 0
+#CHECK-NEXT: Section: Undefined
+#CHECK-NEXT: }
+#CHECK-NEXT: Symbol {
+#CHECK-NEXT: Name: hiddenLocal
+#CHECK-NEXT: Value: 0x1008
+#CHECK-NEXT: Size: 8
+#CHECK-NEXT: Binding: Local
+#CHECK-NEXT: Type: Function
+#CHECK-NEXT: Other [
+#CHECK-NEXT: STV_HIDDEN
+#CHECK-NEXT: ]
+#CHECK-NEXT: Section: .text
+#CHECK-NEXT: }
+#CHECK-NEXT: Symbol {
+#CHECK-NEXT: Name: hiddenGlobal
+#CHECK-NEXT: Value: 0x2006
+#CHECK-NEXT: Size: 2
+#CHECK-NEXT: Binding: Local
+#CHECK-NEXT: Type: Object
+#CHECK-NEXT: Other [
+#CHECK-NEXT: STV_HIDDEN
+#CHECK-NEXT: ]
+#CHECK-NEXT: Section: .data
+#CHECK-NEXT: }
+#CHECK-NEXT: Symbol {
+#CHECK-NEXT: Name: internalGlobal
+#CHECK-NEXT: Value: 0x2002
+#CHECK-NEXT: Size: 2
+#CHECK-NEXT: Binding: Local
+#CHECK-NEXT: Type: Object
+#CHECK-NEXT: Other [
+#CHECK-NEXT: STV_INTERNAL
+#CHECK-NEXT: ]
+#CHECK-NEXT: Section: .data
+#CHECK-NEXT: }
+#CHECK-NEXT: Symbol {
+#CHECK-NEXT: Name: hiddenWeak
+#CHECK-NEXT: Value: 0x1010
+#CHECK-NEXT: Size: 8
+#CHECK-NEXT: Binding: Local
+#CHECK-NEXT: Type: Function
+#CHECK-NEXT: Other [
+#CHECK-NEXT: STV_HIDDEN
+#CHECK-NEXT: ]
+#CHECK-NEXT: Section: .text
+#CHECK-NEXT: }
+#CHECK-NEXT: Symbol {
+#CHECK-NEXT: Name: defaultGlobal
+#CHECK-NEXT: Value: 0x1000
+#CHECK-NEXT: Size: 8
+#CHECK-NEXT: Binding: Global
+#CHECK-NEXT: Type: Function
+#CHECK-NEXT: Other: 0
+#CHECK-NEXT: Section: .text
+#CHECK-NEXT: }
+#CHECK-NEXT: Symbol {
+#CHECK-NEXT: Name: undefGlobal
+#CHECK-NEXT: Value: 0x0
+#CHECK-NEXT: Size: 8
+#CHECK-NEXT: Binding: Global
+#CHECK-NEXT: Type: Function
+#CHECK-NEXT: Other: 0
+#CHECK-NEXT: Section:
+#CHECK-NEXT: }
+#CHECK-NEXT: Symbol {
+#CHECK-NEXT: Name: protectedGlobal
+#CHECK-NEXT: Value: 0x2000
+#CHECK-NEXT: Size: 4
+#CHECK-NEXT: Binding: Global
+#CHECK-NEXT: Type: Object
+#CHECK-NEXT: Other [
+#CHECK-NEXT: STV_PROTECTED
+#CHECK-NEXT: ]
+#CHECK-NEXT: Section: .data
+#CHECK-NEXT: }
+#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=321884&r1=321883&r2=321884&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-objcopy/Object.cpp (original)
+++ llvm/trunk/tools/llvm-objcopy/Object.cpp Fri Jan 5 11:19:09 2018
@@ -175,6 +175,25 @@ void SymbolTableSection::removeSectionRe
Symbols.erase(Iter, std::end(Symbols));
}
+void SymbolTableSection::localize(
+ std::function<bool(const Symbol &)> ToLocalize) {
+ for (const auto &Sym : Symbols) {
+ if (ToLocalize(*Sym))
+ Sym->Binding = STB_LOCAL;
+ }
+
+ // Now that the local symbols aren't grouped at the start we have to reorder
+ // the symbols to respect this property.
+ std::stable_partition(
+ std::begin(Symbols), std::end(Symbols),
+ [](const SymPtr &Sym) { return Sym->Binding == STB_LOCAL; });
+
+ // Lastly we fix the symbol indexes.
+ uint32_t Index = 0;
+ for (auto &Sym : Symbols)
+ Sym->Index = Index++;
+}
+
void SymbolTableSection::initialize(SectionTableRef SecTable) {
Size = 0;
setStrTab(SecTable.getSectionOfType<StringTableSection>(
Modified: llvm/trunk/tools/llvm-objcopy/Object.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-objcopy/Object.h?rev=321884&r1=321883&r2=321884&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-objcopy/Object.h (original)
+++ llvm/trunk/tools/llvm-objcopy/Object.h Fri Jan 5 11:19:09 2018
@@ -214,6 +214,7 @@ public:
const SectionBase *getStrTab() const { return SymbolNames; }
const Symbol *getSymbolByIndex(uint32_t Index) const;
void removeSectionReferences(const SectionBase *Sec) override;
+ void localize(std::function<bool(const Symbol &)> ToLocalize);
void initialize(SectionTableRef SecTable) override;
void finalize() override;
@@ -384,7 +385,7 @@ public:
Object(const object::ELFObjectFile<ELFT> &Obj);
virtual ~Object() = default;
- const SymbolTableSection *getSymTab() const { return SymbolTable; }
+ SymbolTableSection *getSymTab() const { return SymbolTable; }
const SectionBase *getSectionHeaderStrTab() const { return SectionNames; }
void removeSections(std::function<bool(const SectionBase &)> ToRemove);
void addSection(StringRef SecName, ArrayRef<uint8_t> Data);
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=321884&r1=321883&r2=321884&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-objcopy/llvm-objcopy.cpp (original)
+++ llvm/trunk/tools/llvm-objcopy/llvm-objcopy.cpp Fri Jan 5 11:19:09 2018
@@ -117,6 +117,10 @@ static cl::list<std::string> AddSection(
"add-section",
cl::desc("Make a section named <section> with the contents of <file>."),
cl::value_desc("section=file"));
+static cl::opt<bool> LocalizeHidden(
+ "localize-hidden",
+ cl::desc(
+ "Mark all symbols that have hidden or internal visibility as local"));
using SectionPred = std::function<bool(const SectionBase &Sec)>;
@@ -180,6 +184,14 @@ template <class ELFT> void CopyBinary(co
if (!SplitDWO.empty())
SplitDWOToFile<ELFT>(ObjFile, SplitDWO.getValue());
+ // Localize:
+
+ if (LocalizeHidden) {
+ Obj->getSymTab()->localize([](const Symbol &Sym) {
+ return Sym.Visibility == STV_HIDDEN || Sym.Visibility == STV_INTERNAL;
+ });
+ }
+
SectionPred RemovePred = [](const SectionBase &) { return false; };
// Removes:
More information about the llvm-commits
mailing list