Handle relocations that don't point to symbols.

In ELF (as in MachO), not all relocations point to symbols. Represent this
properly by using a symbol_iterator instead of a SymbolRef. Update llvm-readobj
ELF's dumper to handle relocatios without symbols.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183284 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 8 insertions, 16 deletions

diff --git a/lib/Object/COFFObjectFile.cpp b/lib/Object/COFFObjectFile.cpp
index f5b49ab..bc5958d 100644
--- a/lib/Object/COFFObjectFile.cpp
+++ b/lib/Object/COFFObjectFile.cpp
@@ -712,13 +712,11 @@ error_code COFFObjectFile::getRelocationOffset(DataRefImpl Rel,
   Res = toRel(Rel)->VirtualAddress;
   return object_error::success;
 }
-error_code COFFObjectFile::getRelocationSymbol(DataRefImpl Rel,
-                                               SymbolRef &Res) const {
+symbol_iterator COFFObjectFile::getRelocationSymbol(DataRefImpl Rel) const {
   const coff_relocation* R = toRel(Rel);
   DataRefImpl Symb;
   Symb.p = reinterpret_cast<uintptr_t>(SymbolTable + R->SymbolTableIndex);
-  Res = SymbolRef(Symb, this);
-  return object_error::success;
+  return symbol_iterator(SymbolRef(Symb, this));
 }
 error_code COFFObjectFile::getRelocationType(DataRefImpl Rel,
                                              uint64_t &Res) const {
diff --git a/lib/Object/MachOObjectFile.cpp b/lib/Object/MachOObjectFile.cpp
index 654af08..bd5ea57 100644
--- a/lib/Object/MachOObjectFile.cpp
+++ b/lib/Object/MachOObjectFile.cpp
@@ -869,15 +869,13 @@ error_code MachOObjectFile::getRelocationOffset(DataRefImpl Rel,
   return object_error::success;
 }
 
-error_code
-MachOObjectFile::getRelocationSymbol(DataRefImpl Rel, SymbolRef &Res) const {
+symbol_iterator
+MachOObjectFile::getRelocationSymbol(DataRefImpl Rel) const {
   macho::RelocationEntry RE = getRelocation(Rel);
   uint32_t SymbolIdx = getPlainRelocationSymbolNum(RE);
   bool isExtern = getPlainRelocationExternal(RE);
-  if (!isExtern) {
-    Res = *end_symbols();
-    return object_error::success;
-  }
+  if (!isExtern)
+    return end_symbols();
 
   macho::SymtabLoadCommand S = getSymtabLoadCommand();
   unsigned SymbolTableEntrySize = is64Bit() ?
@@ -886,8 +884,7 @@ MachOObjectFile::getRelocationSymbol(DataRefImpl Rel, SymbolRef &Res) const {
   uint64_t Offset = S.SymbolTableOffset + SymbolIdx * SymbolTableEntrySize;
   DataRefImpl Sym;
   Sym.p = reinterpret_cast<uintptr_t>(getPtr(this, Offset));
-  Res = SymbolRef(Sym, this);
-  return object_error::success;
+  return symbol_iterator(SymbolRef(Sym, this));
 }
 
 error_code MachOObjectFile::getRelocationType(DataRefImpl Rel,
diff --git a/lib/Object/Object.cpp b/lib/Object/Object.cpp
index 3e2c78e..6941708 100644
--- a/lib/Object/Object.cpp
+++ b/lib/Object/Object.cpp
@@ -219,10 +219,7 @@ uint64_t LLVMGetRelocationOffset(LLVMRelocationIteratorRef RI) {
 }
 
 LLVMSymbolIteratorRef LLVMGetRelocationSymbol(LLVMRelocationIteratorRef RI) {
-  SymbolRef ret;
-  if (error_code ec = (*unwrap(RI))->getSymbol(ret))
-    report_fatal_error(ec.message());
-
+  symbol_iterator ret = (*unwrap(RI))->getSymbol();
   return wrap(new symbol_iterator(ret));
 }