[lld] r245069 - ELF: Also record the type of undefined symbols.
Rafael Espindola via llvm-commits
llvm-commits at lists.llvm.org
Fri Aug 14 09:46:30 PDT 2015
Author: rafael
Date: Fri Aug 14 11:46:28 2015
New Revision: 245069
URL: http://llvm.org/viewvc/llvm-project?rev=245069&view=rev
Log:
ELF: Also record the type of undefined symbols.
Tested with a weak undefined. Testing with a plain undefined will have to wait
for support for -shared.
Modified:
lld/trunk/ELF/InputFiles.cpp
lld/trunk/ELF/SymbolTable.cpp
lld/trunk/ELF/Symbols.cpp
lld/trunk/ELF/Symbols.h
lld/trunk/ELF/Writer.cpp
lld/trunk/test/elf2/symbols.s
Modified: lld/trunk/ELF/InputFiles.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/InputFiles.cpp?rev=245069&r1=245068&r2=245069&view=diff
==============================================================================
--- lld/trunk/ELF/InputFiles.cpp (original)
+++ lld/trunk/ELF/InputFiles.cpp Fri Aug 14 11:46:28 2015
@@ -86,11 +86,11 @@ SymbolBody *elf2::ObjectFile<ELFT>::crea
error("unexpected binding");
case STB_GLOBAL:
if (Sym->isUndefined())
- return new (Alloc) Undefined(Name);
+ return new (Alloc) Undefined<ELFT>(Name, *Sym);
return new (Alloc) DefinedRegular<ELFT>(Name, *Sym);
case STB_WEAK:
if (Sym->isUndefined())
- return new (Alloc) UndefinedWeak(Name);
+ return new (Alloc) UndefinedWeak<ELFT>(Name, *Sym);
return new (Alloc) DefinedWeak<ELFT>(Name, *Sym);
}
}
Modified: lld/trunk/ELF/SymbolTable.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/SymbolTable.cpp?rev=245069&r1=245068&r2=245069&view=diff
==============================================================================
--- lld/trunk/ELF/SymbolTable.cpp (original)
+++ lld/trunk/ELF/SymbolTable.cpp Fri Aug 14 11:46:28 2015
@@ -16,7 +16,9 @@ using namespace llvm;
using namespace lld;
using namespace lld::elf2;
-SymbolTable::SymbolTable() { resolve(new (Alloc) Undefined("_start")); }
+SymbolTable::SymbolTable() {
+ resolve(new (Alloc) SyntheticUndefined("_start"));
+}
void SymbolTable::addFile(std::unique_ptr<InputFile> File) {
File->parse();
@@ -39,9 +41,9 @@ void SymbolTable::addObject(ObjectFileBa
void SymbolTable::reportRemainingUndefines() {
for (auto &I : Symtab) {
- Symbol *Sym = I.second;
- if (auto *Undef = dyn_cast<Undefined>(Sym->Body))
- error(Twine("undefined symbol: ") + Undef->getName());
+ SymbolBody *Body = I.second->Body;
+ if (Body->isStrongUndefined())
+ error(Twine("undefined symbol: ") + Body->getName());
}
}
Modified: lld/trunk/ELF/Symbols.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Symbols.cpp?rev=245069&r1=245068&r2=245069&view=diff
==============================================================================
--- lld/trunk/ELF/Symbols.cpp (original)
+++ lld/trunk/ELF/Symbols.cpp Fri Aug 14 11:46:28 2015
@@ -38,6 +38,7 @@ int SymbolBody::compare(SymbolBody *Othe
case DefinedWeakKind:
case UndefinedKind:
case UndefinedWeakKind:
+ case UndefinedSyntheticKind:
return 1;
}
llvm_unreachable("unknown symbol kind");
Modified: lld/trunk/ELF/Symbols.h
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Symbols.h?rev=245069&r1=245068&r2=245069&view=diff
==============================================================================
--- lld/trunk/ELF/Symbols.h (original)
+++ lld/trunk/ELF/Symbols.h Fri Aug 14 11:46:28 2015
@@ -40,11 +40,16 @@ public:
DefinedWeakKind = 1,
DefinedLast = 1,
UndefinedWeakKind = 2,
- UndefinedKind = 3
+ UndefinedKind = 3,
+ UndefinedSyntheticKind = 4
};
Kind kind() const { return static_cast<Kind>(SymbolKind); }
+ bool isStrongUndefined() {
+ return SymbolKind == UndefinedKind || SymbolKind == UndefinedSyntheticKind;
+ }
+
// Returns the symbol name.
StringRef getName() const { return Name; }
@@ -70,19 +75,43 @@ protected:
Symbol *Backref = nullptr;
};
+// This is for symbols created from elf files and not from the command line.
+// Since they come from object files, they have a Elf_Sym.
+//
+// FIXME: Another alternative is to give every symbol an Elf_Sym. To do that
+// we have to delay creating the symbol table until the output format is
+// known and some of its methods will be templated. We should experiment with
+// that once we have a bit more code.
+template <class ELFT> class ELFSymbolBody : public SymbolBody {
+protected:
+ typedef typename llvm::object::ELFFile<ELFT>::Elf_Sym Elf_Sym;
+ ELFSymbolBody(Kind K, StringRef Name, const Elf_Sym &Sym)
+ : SymbolBody(K, Name), Sym(Sym) {}
+
+public:
+ const Elf_Sym &Sym;
+
+ static bool classof(const SymbolBody *S) {
+ Kind K = S->kind();
+ return K >= DefinedFirst && K <= UndefinedKind;
+ }
+};
+
// The base class for any defined symbols, including absolute symbols,
// etc.
-template <class ELFT> class Defined : public SymbolBody {
+template <class ELFT> class Defined : public ELFSymbolBody<ELFT> {
+ typedef ELFSymbolBody<ELFT> Base;
+ typedef typename Base::Kind Kind;
+
public:
- typedef typename llvm::object::ELFFile<ELFT>::Elf_Sym Elf_Sym;
- const Elf_Sym &Sym;
+ typedef typename Base::Elf_Sym Elf_Sym;
explicit Defined(Kind K, StringRef N, const Elf_Sym &Sym)
- : SymbolBody(K, N), Sym(Sym) {}
+ : ELFSymbolBody<ELFT>(K, N, Sym) {}
static bool classof(const SymbolBody *S) {
Kind K = S->kind();
- return DefinedFirst <= K && K <= DefinedLast;
+ return Base::DefinedFirst <= K && K <= Base::DefinedLast;
}
};
@@ -114,21 +143,38 @@ public:
};
// Undefined symbols.
-class Undefined : public SymbolBody {
+class SyntheticUndefined : public SymbolBody {
public:
- explicit Undefined(StringRef N) : SymbolBody(UndefinedKind, N) {}
+ explicit SyntheticUndefined(StringRef N) : SymbolBody(UndefinedKind, N) {}
static bool classof(const SymbolBody *S) {
return S->kind() == UndefinedKind;
}
};
-class UndefinedWeak : public SymbolBody {
+template <class ELFT> class Undefined : public ELFSymbolBody<ELFT> {
+ typedef ELFSymbolBody<ELFT> Base;
+ typedef typename Base::Elf_Sym Elf_Sym;
+
+public:
+ explicit Undefined(StringRef N, const Elf_Sym &Sym)
+ : ELFSymbolBody<ELFT>(Base::UndefinedKind, N, Sym) {}
+
+ static bool classof(const SymbolBody *S) {
+ return S->kind() == Base::UndefinedKind;
+ }
+};
+
+template <class ELFT> class UndefinedWeak : public ELFSymbolBody<ELFT> {
+ typedef ELFSymbolBody<ELFT> Base;
+ typedef typename Base::Elf_Sym Elf_Sym;
+
public:
- explicit UndefinedWeak(StringRef N) : SymbolBody(UndefinedWeakKind, N) {}
+ explicit UndefinedWeak(StringRef N, const Elf_Sym &Sym)
+ : ELFSymbolBody<ELFT>(Base::UndefinedWeakKind, N, Sym) {}
static bool classof(const SymbolBody *S) {
- return S->kind() == UndefinedWeakKind;
+ return S->kind() == Base::UndefinedWeakKind;
}
};
Modified: lld/trunk/ELF/Writer.cpp
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/ELF/Writer.cpp?rev=245069&r1=245068&r2=245069&view=diff
==============================================================================
--- lld/trunk/ELF/Writer.cpp (original)
+++ lld/trunk/ELF/Writer.cpp Fri Aug 14 11:46:28 2015
@@ -224,16 +224,16 @@ template <class ELFT> void SymbolTableSe
uint8_t Type = 0;
switch (Body->kind()) {
case SymbolBody::UndefinedKind:
+ case SymbolBody::UndefinedSyntheticKind:
llvm_unreachable("Should be defined by now");
case SymbolBody::DefinedRegularKind:
Binding = STB_GLOBAL;
Type = cast<DefinedRegular<ELFT>>(Body)->Sym.getType();
break;
case SymbolBody::DefinedWeakKind:
- Type = cast<DefinedWeak<ELFT>>(Body)->Sym.getType();
- // Fallthrough
case SymbolBody::UndefinedWeakKind:
Binding = STB_WEAK;
+ Type = cast<ELFSymbolBody<ELFT>>(Body)->Sym.getType();
break;
}
ESym->setBindingAndType(Binding, Type);
Modified: lld/trunk/test/elf2/symbols.s
URL: http://llvm.org/viewvc/llvm-project/lld/trunk/test/elf2/symbols.s?rev=245069&r1=245068&r2=245069&view=diff
==============================================================================
--- lld/trunk/test/elf2/symbols.s (original)
+++ lld/trunk/test/elf2/symbols.s Fri Aug 14 11:46:28 2015
@@ -11,6 +11,10 @@ _start:
.weak foo
foo:
+.type bar, @object
+.weak bar
+.long bar
+
// CHECK: Symbols [
// CHECK-NEXT: Symbol {
// CHECK-NEXT: Name: (0)
@@ -30,6 +34,15 @@ foo:
// CHECK-NEXT: Other: 0
// CHECK-NEXT: Section: Undefined (0x0)
// CHECK-NEXT: }
+// CHECK-NEXT: Symbol {
+// CHECK-NEXT: Name: bar
+// CHECK-NEXT: Value: 0x0
+// CHECK-NEXT: Size: 0
+// CHECK-NEXT: Binding: Weak (0x2)
+// CHECK-NEXT: Type: Object (0x1)
+// CHECK-NEXT: Other: 0
+// CHECK-NEXT: Section: Undefined (0x0)
+// CHECK-NEXT: }
// CHECK-NEXT: Symbol {
// CHECK-NEXT: Name: foo
// CHECK-NEXT: Value: 0x0
More information about the llvm-commits
mailing list