[lld] r245868 - Start recording the section of symbols in the symbol table.
Rafael Espindola via llvm-commits
llvm-commits at lists.llvm.org
Mon Aug 24 13:06:33 PDT 2015
Author: rafael
Date: Mon Aug 24 15:06:32 2015
New Revision: 245868
URL: http://llvm.org/viewvc/llvm-project?rev=245868&view=rev
Log:
Start recording the section of symbols in the symbol table.
Support for more than 64 K sections to follow shortly.
Modified:
lld/trunk/ELF/Chunks.h
lld/trunk/ELF/InputFiles.cpp
lld/trunk/ELF/Symbols.h
lld/trunk/ELF/Writer.cpp
lld/trunk/test/elf2/symbols.s
Modified: lld/trunk/ELF/Chunks.h
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Chunks.h?rev=245868&r1=245867&r2=245868&view=diff
==============================================================================
--- lld/trunk/ELF/Chunks.h (original)
+++ lld/trunk/ELF/Chunks.h Mon Aug 24 15:06:32 2015
@@ -17,6 +17,7 @@ namespace lld {
namespace elf2 {
template <class ELFT> class ObjectFile;
+template <class ELFT> class OutputSection;
// A chunk corresponding a section of an input file.
template <class ELFT> class SectionChunk {
@@ -43,6 +44,9 @@ public:
uintX_t getAlign() { return Header->sh_addralign; }
void setOutputSectionOff(uint64_t V) { OutputSectionOff = V; }
+ void setOutputSection(OutputSection<ELFT> *O) { Out = O; }
+ OutputSection<ELFT> *getOutputSection() const { return Out; }
+
private:
// The offset from beginning of the output sections this chunk was assigned
// to. The writer sets a value.
@@ -51,6 +55,8 @@ private:
// A file this chunk was created from.
llvm::object::ELFFile<ELFT> *Obj;
+ OutputSection<ELFT> *Out = nullptr;
+
const Elf_Shdr *Header;
};
Modified: lld/trunk/ELF/InputFiles.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/InputFiles.cpp?rev=245868&r1=245867&r2=245868&view=diff
==============================================================================
--- lld/trunk/ELF/InputFiles.cpp (original)
+++ lld/trunk/ELF/InputFiles.cpp Mon Aug 24 15:06:32 2015
@@ -39,7 +39,8 @@ template <class ELFT> void elf2::ObjectF
template <class ELFT> void elf2::ObjectFile<ELFT>::initializeChunks() {
uint64_t Size = ELFObj->getNumSections();
- Chunks.reserve(Size);
+ Chunks.resize(Size);
+ unsigned I = 0;
for (const Elf_Shdr &Sec : ELFObj->sections()) {
switch (Sec.sh_type) {
case SHT_SYMTAB:
@@ -51,10 +52,10 @@ template <class ELFT> void elf2::ObjectF
case SHT_REL:
break;
default:
- auto *C = new (Alloc) SectionChunk<ELFT>(this->getObj(), &Sec);
- Chunks.push_back(C);
+ Chunks[I] = new (Alloc) SectionChunk<ELFT>(this->getObj(), &Sec);
break;
}
+ ++I;
}
}
@@ -81,17 +82,18 @@ SymbolBody *elf2::ObjectFile<ELFT>::crea
ErrorOr<StringRef> NameOrErr = Sym->getName(StringTable);
error(NameOrErr.getError());
StringRef Name = *NameOrErr;
+ uint16_t SecIndex = Sym->st_shndx;
switch (Sym->getBinding()) {
default:
error("unexpected binding");
case STB_GLOBAL:
if (Sym->isUndefined())
return new (Alloc) Undefined<ELFT>(Name, *Sym);
- return new (Alloc) DefinedRegular<ELFT>(Name, *Sym);
+ return new (Alloc) DefinedRegular<ELFT>(Name, *Sym, *Chunks[SecIndex]);
case STB_WEAK:
if (Sym->isUndefined())
return new (Alloc) UndefinedWeak<ELFT>(Name, *Sym);
- return new (Alloc) DefinedWeak<ELFT>(Name, *Sym);
+ return new (Alloc) DefinedWeak<ELFT>(Name, *Sym, *Chunks[SecIndex]);
}
}
Modified: lld/trunk/ELF/Symbols.h
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Symbols.h?rev=245868&r1=245867&r2=245868&view=diff
==============================================================================
--- lld/trunk/ELF/Symbols.h (original)
+++ lld/trunk/ELF/Symbols.h Mon Aug 24 15:06:32 2015
@@ -10,6 +10,8 @@
#ifndef LLD_ELF_SYMBOLS_H
#define LLD_ELF_SYMBOLS_H
+#include "Chunks.h"
+
#include "lld/Core/LLVM.h"
#include "llvm/Object/ELF.h"
@@ -106,13 +108,16 @@ template <class ELFT> class Defined : pu
public:
typedef typename Base::Elf_Sym Elf_Sym;
- explicit Defined(Kind K, StringRef N, const Elf_Sym &Sym)
- : ELFSymbolBody<ELFT>(K, N, Sym) {}
+ explicit Defined(Kind K, StringRef N, const Elf_Sym &Sym,
+ SectionChunk<ELFT> &Section)
+ : ELFSymbolBody<ELFT>(K, N, Sym), Section(Section) {}
static bool classof(const SymbolBody *S) {
Kind K = S->kind();
return Base::DefinedFirst <= K && K <= Base::DefinedLast;
}
+
+ const SectionChunk<ELFT> &Section;
};
// Regular defined symbols read from object file symbol tables.
@@ -121,8 +126,9 @@ template <class ELFT> class DefinedRegul
typedef typename Base::Elf_Sym Elf_Sym;
public:
- explicit DefinedRegular(StringRef N, const Elf_Sym &Sym)
- : Defined<ELFT>(Base::DefinedRegularKind, N, Sym) {}
+ explicit DefinedRegular(StringRef N, const Elf_Sym &Sym,
+ SectionChunk<ELFT> &Section)
+ : Defined<ELFT>(Base::DefinedRegularKind, N, Sym, Section) {}
static bool classof(const SymbolBody *S) {
return S->kind() == Base::DefinedRegularKind;
@@ -134,8 +140,9 @@ template <class ELFT> class DefinedWeak
typedef typename Base::Elf_Sym Elf_Sym;
public:
- explicit DefinedWeak(StringRef N, const Elf_Sym &Sym)
- : Defined<ELFT>(Base::DefinedWeakKind, N, Sym) {}
+ explicit DefinedWeak(StringRef N, const Elf_Sym &Sym,
+ SectionChunk<ELFT> &Section)
+ : Defined<ELFT>(Base::DefinedWeakKind, N, Sym, Section) {}
static bool classof(const SymbolBody *S) {
return S->kind() == Base::DefinedWeakKind;
Modified: lld/trunk/ELF/Writer.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Writer.cpp?rev=245868&r1=245867&r2=245868&view=diff
==============================================================================
--- lld/trunk/ELF/Writer.cpp (original)
+++ lld/trunk/ELF/Writer.cpp Mon Aug 24 15:06:32 2015
@@ -51,6 +51,9 @@ public:
StringRef getName() { return Name; }
void setNameOffset(uintX_t Offset) { Header.sh_name = Offset; }
+ unsigned getSectionIndex() const { return SectionIndex; }
+ void setSectionIndex(unsigned I) { SectionIndex = I; }
+
// Returns the size of the section in the output file.
uintX_t getSize() { return Header.sh_size; }
uintX_t getFlags() { return Header.sh_flags; }
@@ -63,11 +66,14 @@ public:
protected:
StringRef Name;
HeaderT Header;
+ unsigned SectionIndex;
~OutputSectionBase() = default;
};
+}
template <class ELFT>
-class OutputSection final : public OutputSectionBase<ELFT::Is64Bits> {
+class lld::elf2::OutputSection final
+ : public OutputSectionBase<ELFT::Is64Bits> {
public:
typedef typename OutputSectionBase<ELFT::Is64Bits>::uintX_t uintX_t;
OutputSection(StringRef Name, uint32_t sh_type, uintX_t sh_flags)
@@ -80,6 +86,7 @@ private:
std::vector<SectionChunk<ELFT> *> Chunks;
};
+namespace {
template <bool Is64Bits>
class StringTableSection final : public OutputSectionBase<Is64Bits> {
llvm::StringTableBuilder &StrTabBuilder;
@@ -159,6 +166,11 @@ private:
StringTableSection<ELFT::Is64Bits> StringTable;
unsigned NumSections;
+
+ void addOutputSection(OutputSectionBase<ELFT::Is64Bits> *Sec) {
+ OutputSections.push_back(Sec);
+ Sec->setSectionIndex(OutputSections.size());
+ }
};
} // anonymous namespace
@@ -189,6 +201,7 @@ template <class ELFT> void Writer<ELFT>:
template <class ELFT>
void OutputSection<ELFT>::addChunk(SectionChunk<ELFT> *C) {
Chunks.push_back(C);
+ C->setOutputSection(this);
uint32_t Align = C->getAlign();
if (Align > this->Header.sh_addralign)
this->Header.sh_addralign = Align;
@@ -223,15 +236,22 @@ template <class ELFT> void SymbolTableSe
uint8_t Binding;
SymbolBody *Body = Sym->Body;
uint8_t Type = 0;
+
+ const SectionChunk<ELFT> *Section = nullptr;
+
switch (Body->kind()) {
case SymbolBody::UndefinedKind:
case SymbolBody::UndefinedSyntheticKind:
llvm_unreachable("Should be defined by now");
- case SymbolBody::DefinedRegularKind:
+ case SymbolBody::DefinedRegularKind: {
Binding = STB_GLOBAL;
- Type = cast<DefinedRegular<ELFT>>(Body)->Sym.getType();
+ auto *Def = cast<DefinedRegular<ELFT>>(Body);
+ Type = Def->Sym.getType();
+ Section = &Def->Section;
break;
+ }
case SymbolBody::DefinedWeakKind:
+ Section = &cast<Defined<ELFT>>(Body)->Section;
case SymbolBody::UndefinedWeakKind:
Binding = STB_WEAK;
Type = cast<ELFSymbolBody<ELFT>>(Body)->Sym.getType();
@@ -239,6 +259,11 @@ template <class ELFT> void SymbolTableSe
}
ESym->setBindingAndType(Binding, Type);
+ if (Section) {
+ OutputSection<ELFT> *Out = Section->getOutputSection();
+ ESym->st_shndx = Out->getSectionIndex();
+ }
+
Buf += sizeof(Elf_Sym);
}
}
@@ -294,6 +319,8 @@ template <class ELFT> void Writer<ELFT>:
for (const std::unique_ptr<ObjectFileBase> &FileB : Symtab.ObjectFiles) {
auto &File = cast<ObjectFile<ELFT>>(*FileB);
for (SectionChunk<ELFT> *C : File.getChunks()) {
+ if (!C)
+ continue;
const Elf_Shdr *H = C->getSectionHdr();
SectionKey<ELFT::Is64Bits> Key{C->getSectionName(), H->sh_type,
H->sh_flags};
@@ -301,7 +328,7 @@ template <class ELFT> void Writer<ELFT>:
if (!Sec) {
Sec = new (CAlloc.Allocate())
OutputSection<ELFT>(Key.Name, Key.sh_type, Key.sh_flags);
- OutputSections.push_back(Sec);
+ addOutputSection(Sec);
}
Sec->addChunk(C);
}
@@ -325,8 +352,8 @@ template <class ELFT> void Writer<ELFT>:
std::stable_sort(OutputSections.begin(), OutputSections.end(),
compSec<ELFT::Is64Bits>);
- OutputSections.push_back(&SymTable);
- OutputSections.push_back(&StringTable);
+ addOutputSection(&SymTable);
+ addOutputSection(&StringTable);
StringTableIndex = OutputSections.size();
SymTable.setStringTableIndex(StringTableIndex);
Modified: lld/trunk/test/elf2/symbols.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/elf2/symbols.s?rev=245868&r1=245867&r2=245868&view=diff
==============================================================================
--- lld/trunk/test/elf2/symbols.s (original)
+++ lld/trunk/test/elf2/symbols.s Mon Aug 24 15:06:32 2015
@@ -15,6 +15,10 @@ foo:
.weak bar
.long bar
+.data
+.globl zed
+zed:
+
// CHECK: Symbols [
// CHECK-NEXT: Symbol {
// CHECK-NEXT: Name: (0)
@@ -26,13 +30,22 @@ foo:
// CHECK-NEXT: Section: Undefined (0x0)
// CHECK-NEXT: }
// CHECK-NEXT: Symbol {
+// CHECK-NEXT: Name: zed
+// CHECK-NEXT: Value: 0x0
+// CHECK-NEXT: Size: 0
+// CHECK-NEXT: Binding: Global (0x1)
+// CHECK-NEXT: Type: None
+// CHECK-NEXT: Other: 0
+// CHECK-NEXT: Section: .data
+// CHECK-NEXT: }
+// CHECK-NEXT: Symbol {
// CHECK-NEXT: Name: _start
// CHECK-NEXT: Value: 0x0
// CHECK-NEXT: Size: 0
// CHECK-NEXT: Binding: Global (0x1)
// CHECK-NEXT: Type: Function
// CHECK-NEXT: Other: 0
-// CHECK-NEXT: Section: Undefined (0x0)
+// CHECK-NEXT: Section: .text
// CHECK-NEXT: }
// CHECK-NEXT: Symbol {
// CHECK-NEXT: Name: bar
@@ -50,6 +63,6 @@ foo:
// CHECK-NEXT: Binding: Weak (0x2)
// CHECK-NEXT: Type: Object
// CHECK-NEXT: Other: 0
-// CHECK-NEXT: Section: Undefined (0x0)
+// CHECK-NEXT: Section: .text
// CHECK-NEXT: }
// CHECK-NEXT: ]
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