[yaml2obj] - Allow setting st_value explicitly for Symbol.
In some cases it is useful to explicitly set symbol's st_name value.
For example, I am using it in a patch for LLD to remove the broken
binary from a test case and replace it with a YAML test.
Differential revision: https://reviews.llvm.org/D61180
llvm-svn: 360137
diff --git a/llvm/tools/yaml2obj/yaml2elf.cpp b/llvm/tools/yaml2obj/yaml2elf.cpp
index 574e5db..48da026 100644
--- a/llvm/tools/yaml2obj/yaml2elf.cpp
+++ b/llvm/tools/yaml2obj/yaml2elf.cpp
@@ -57,34 +57,34 @@
} // end anonymous namespace
// Used to keep track of section and symbol names, so that in the YAML file
-// sections and symbols can be referenced by name instead of by index.
-namespace {
-class NameToIdxMap {
+// sections and symbols can be referenced by name instead of by index.
+namespace {
+class NameToIdxMap {
StringMap<unsigned> Map;
-public:
+public:
/// \Returns false if name is already present in the map.
bool addName(StringRef Name, unsigned Ndx) {
return Map.insert({Name, Ndx}).second;
- }
+ }
/// \Returns false if name is not present in the map.
- bool lookup(StringRef Name, unsigned &Idx) const {
+ bool lookup(StringRef Name, unsigned &Idx) const {
auto I = Map.find(Name);
- if (I == Map.end())
+ if (I == Map.end())
return false;
- Idx = I->getValue();
+ Idx = I->getValue();
return true;
- }
+ }
/// Asserts if name is not present in the map.
- unsigned get(StringRef Name) const {
+ unsigned get(StringRef Name) const {
unsigned Idx;
if (lookup(Name, Idx))
return Idx;
assert(false && "Expected section not found in index");
return 0;
- }
- unsigned size() const { return Map.size(); }
-};
+ }
+ unsigned size() const { return Map.size(); }
+};
} // end anonymous namespace
template <class T>
@@ -236,13 +236,13 @@
PHeaders.push_back(Phdr);
}
}
-
-static bool convertSectionIndex(NameToIdxMap &SN2I, StringRef SecName,
- StringRef IndexSrc, unsigned &IndexDest) {
+
+static bool convertSectionIndex(NameToIdxMap &SN2I, StringRef SecName,
+ StringRef IndexSrc, unsigned &IndexDest) {
if (!SN2I.lookup(IndexSrc, IndexDest) && !to_integer(IndexSrc, IndexDest)) {
- WithColor::error() << "Unknown section referenced: '" << IndexSrc
- << "' at YAML section '" << SecName << "'.\n";
- return false;
+ WithColor::error() << "Unknown section referenced: '" << IndexSrc
+ << "' at YAML section '" << SecName << "'.\n";
+ return false;
}
return true;
}
@@ -468,15 +468,22 @@
for (const auto &Sym : Symbols) {
Elf_Sym Symbol;
zero(Symbol);
- if (!Sym.Name.empty())
+
+ // If NameIndex, which contains the name offset, is explicitly specified, we
+ // use it. This is useful for preparing broken objects. Otherwise, we add
+ // the specified Name to the string table builder to get its offset.
+ if (Sym.NameIndex)
+ Symbol.st_name = *Sym.NameIndex;
+ else if (!Sym.Name.empty())
Symbol.st_name = Strtab.getOffset(Sym.Name);
- Symbol.setBindingAndType(Sym.Binding, Sym.Type);
- if (!Sym.Section.empty()) {
- unsigned Index;
+
+ Symbol.setBindingAndType(Sym.Binding, Sym.Type);
+ if (!Sym.Section.empty()) {
+ unsigned Index;
if (!SN2I.lookup(Sym.Section, Index)) {
- WithColor::error() << "Unknown section referenced: '" << Sym.Section
- << "' by YAML symbol " << Sym.Name << ".\n";
- exit(1);
+ WithColor::error() << "Unknown section referenced: '" << Sym.Section
+ << "' by YAML symbol " << Sym.Name << ".\n";
+ exit(1);
}
Symbol.st_shndx = Index;
} else if (Sym.Index) {
@@ -544,13 +551,13 @@
auto &OS = CBA.getOSAndAlignedOffset(SHeader.sh_offset, SHeader.sh_addralign);
for (const auto &Rel : Section.Relocations) {
- unsigned SymIdx = 0;
- // If a relocation references a symbol, try to look one up in the symbol
- // table. If it is not there, treat the value as a symbol index.
+ unsigned SymIdx = 0;
+ // If a relocation references a symbol, try to look one up in the symbol
+ // table. If it is not there, treat the value as a symbol index.
if (Rel.Symbol && !SymN2I.lookup(*Rel.Symbol, SymIdx) &&
- !to_integer(*Rel.Symbol, SymIdx)) {
- WithColor::error() << "Unknown symbol referenced: '" << *Rel.Symbol
- << "' at YAML section '" << Section.Name << "'.\n";
+ !to_integer(*Rel.Symbol, SymIdx)) {
+ WithColor::error() << "Unknown symbol referenced: '" << *Rel.Symbol
+ << "' at YAML section '" << Section.Name << "'.\n";
return false;
}
@@ -580,8 +587,8 @@
"Section type is not SHT_GROUP");
SHeader.sh_entsize = 4;
- SHeader.sh_size = SHeader.sh_entsize * Section.Members.size();
-
+ SHeader.sh_size = SHeader.sh_entsize * Section.Members.size();
+
unsigned SymIdx;
if (!SymN2I.lookup(Section.Signature, SymIdx) &&
!to_integer(Section.Signature, SymIdx)) {
@@ -781,13 +788,13 @@
template <class ELFT> bool ELFState<ELFT>::buildSectionIndex() {
for (unsigned i = 0, e = Doc.Sections.size(); i != e; ++i) {
- StringRef Name = Doc.Sections[i]->Name;
- DotShStrtab.add(Name);
- // "+ 1" to take into account the SHT_NULL entry.
+ StringRef Name = Doc.Sections[i]->Name;
+ DotShStrtab.add(Name);
+ // "+ 1" to take into account the SHT_NULL entry.
if (!SN2I.addName(Name, i + 1)) {
- WithColor::error() << "Repeated section name: '" << Name
- << "' at YAML section number " << i << ".\n";
- return false;
+ WithColor::error() << "Repeated section name: '" << Name
+ << "' at YAML section number " << i << ".\n";
+ return false;
}
}
@@ -817,13 +824,13 @@
"' after global in Symbols list.\n";
return false;
}
- if (Sym.Binding.value != ELF::STB_LOCAL)
- GlobalSymbolSeen = true;
-
+ if (Sym.Binding.value != ELF::STB_LOCAL)
+ GlobalSymbolSeen = true;
+
if (!Name.empty() && !SymN2I.addName(Name, I)) {
- WithColor::error() << "Repeated symbol name: '" << Name << "'.\n";
- return false;
- }
+ WithColor::error() << "Repeated symbol name: '" << Name << "'.\n";
+ return false;
+ }
}
return true;
}