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-rw-r--r--lib/MC/MachObjectWriter.cpp82
1 files changed, 31 insertions, 51 deletions
diff --git a/lib/MC/MachObjectWriter.cpp b/lib/MC/MachObjectWriter.cpp
index 5214398..577c4b7 100644
--- a/lib/MC/MachObjectWriter.cpp
+++ b/lib/MC/MachObjectWriter.cpp
@@ -41,7 +41,7 @@ void MachObjectWriter::reset() {
bool MachObjectWriter::
doesSymbolRequireExternRelocation(const MCSymbolData *SD) {
// Undefined symbols are always extern.
- if (SD->Symbol->isUndefined())
+ if (SD->getSymbol().isUndefined())
return true;
// References to weak definitions require external relocation entries; the
@@ -84,7 +84,7 @@ uint64_t MachObjectWriter::getSymbolAddress(const MCSymbolData* SD,
MCValue Target;
- if (!S.getVariableValue()->EvaluateAsRelocatable(Target, &Layout))
+ if (!S.getVariableValue()->EvaluateAsRelocatable(Target, &Layout, nullptr))
report_fatal_error("unable to evaluate offset for variable '" +
S.getName() + "'");
@@ -525,15 +525,10 @@ void MachObjectWriter::BindIndirectSymbols(MCAssembler &Asm) {
}
/// ComputeSymbolTable - Compute the symbol table data
-///
-/// \param StringTable [out] - The string table data.
-/// \param StringIndexMap [out] - Map from symbol names to offsets in the
-/// string table.
-void MachObjectWriter::
-ComputeSymbolTable(MCAssembler &Asm, SmallString<256> &StringTable,
- std::vector<MachSymbolData> &LocalSymbolData,
- std::vector<MachSymbolData> &ExternalSymbolData,
- std::vector<MachSymbolData> &UndefinedSymbolData) {
+void MachObjectWriter::ComputeSymbolTable(
+ MCAssembler &Asm, std::vector<MachSymbolData> &LocalSymbolData,
+ std::vector<MachSymbolData> &ExternalSymbolData,
+ std::vector<MachSymbolData> &UndefinedSymbolData) {
// Build section lookup table.
DenseMap<const MCSection*, uint8_t> SectionIndexMap;
unsigned Index = 1;
@@ -542,37 +537,34 @@ ComputeSymbolTable(MCAssembler &Asm, SmallString<256> &StringTable,
SectionIndexMap[&it->getSection()] = Index;
assert(Index <= 256 && "Too many sections!");
- // Index 0 is always the empty string.
- StringMap<uint64_t> StringIndexMap;
- StringTable += '\x00';
+ // Build the string table.
+ for (MCSymbolData &SD : Asm.symbols()) {
+ const MCSymbol &Symbol = SD.getSymbol();
+ if (!Asm.isSymbolLinkerVisible(Symbol))
+ continue;
+
+ StringTable.add(Symbol.getName());
+ }
+ StringTable.finalize(StringTableBuilder::MachO);
- // Build the symbol arrays and the string table, but only for non-local
- // symbols.
+ // Build the symbol arrays but only for non-local symbols.
//
- // The particular order that we collect the symbols and create the string
- // table, then sort the symbols is chosen to match 'as'. Even though it
- // doesn't matter for correctness, this is important for letting us diff .o
- // files.
+ // The particular order that we collect and then sort the symbols is chosen to
+ // match 'as'. Even though it doesn't matter for correctness, this is
+ // important for letting us diff .o files.
for (MCSymbolData &SD : Asm.symbols()) {
const MCSymbol &Symbol = SD.getSymbol();
// Ignore non-linker visible symbols.
- if (!Asm.isSymbolLinkerVisible(SD.getSymbol()))
+ if (!Asm.isSymbolLinkerVisible(Symbol))
continue;
if (!SD.isExternal() && !Symbol.isUndefined())
continue;
- uint64_t &Entry = StringIndexMap[Symbol.getName()];
- if (!Entry) {
- Entry = StringTable.size();
- StringTable += Symbol.getName();
- StringTable += '\x00';
- }
-
MachSymbolData MSD;
MSD.SymbolData = &SD;
- MSD.StringIndex = Entry;
+ MSD.StringIndex = StringTable.getOffset(Symbol.getName());
if (Symbol.isUndefined()) {
MSD.SectionIndex = 0;
@@ -592,22 +584,15 @@ ComputeSymbolTable(MCAssembler &Asm, SmallString<256> &StringTable,
const MCSymbol &Symbol = SD.getSymbol();
// Ignore non-linker visible symbols.
- if (!Asm.isSymbolLinkerVisible(SD.getSymbol()))
+ if (!Asm.isSymbolLinkerVisible(Symbol))
continue;
if (SD.isExternal() || Symbol.isUndefined())
continue;
- uint64_t &Entry = StringIndexMap[Symbol.getName()];
- if (!Entry) {
- Entry = StringTable.size();
- StringTable += Symbol.getName();
- StringTable += '\x00';
- }
-
MachSymbolData MSD;
MSD.SymbolData = &SD;
- MSD.StringIndex = Entry;
+ MSD.StringIndex = StringTable.getOffset(Symbol.getName());
if (Symbol.isAbsolute()) {
MSD.SectionIndex = 0;
@@ -631,10 +616,6 @@ ComputeSymbolTable(MCAssembler &Asm, SmallString<256> &StringTable,
ExternalSymbolData[i].SymbolData->setIndex(Index++);
for (unsigned i = 0, e = UndefinedSymbolData.size(); i != e; ++i)
UndefinedSymbolData[i].SymbolData->setIndex(Index++);
-
- // The string table is padded to a multiple of 4.
- while (StringTable.size() % 4)
- StringTable += '\x00';
}
void MachObjectWriter::computeSectionAddresses(const MCAssembler &Asm,
@@ -664,7 +645,7 @@ void MachObjectWriter::markAbsoluteVariableSymbols(MCAssembler &Asm,
// and neither symbol is external, mark the variable as absolute.
const MCExpr *Expr = SD.getSymbol().getVariableValue();
MCValue Value;
- if (Expr->EvaluateAsRelocatable(Value, &Layout)) {
+ if (Expr->EvaluateAsRelocatable(Value, &Layout, nullptr)) {
if (Value.getSymA() && Value.getSymB())
const_cast<MCSymbol*>(&SD.getSymbol())->setAbsolute();
}
@@ -683,7 +664,7 @@ void MachObjectWriter::ExecutePostLayoutBinding(MCAssembler &Asm,
markAbsoluteVariableSymbols(Asm, Layout);
// Compute symbol table information and bind symbol indices.
- ComputeSymbolTable(Asm, StringTable, LocalSymbolData, ExternalSymbolData,
+ ComputeSymbolTable(Asm, LocalSymbolData, ExternalSymbolData,
UndefinedSymbolData);
}
@@ -745,6 +726,10 @@ IsSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm,
return false;
}
+ // If they are not in the same section, we can't compute the diff.
+ if (&SecA != &SecB)
+ return false;
+
const MCFragment *FA = Asm.getSymbolData(SA).getFragment();
// Bail if the symbol has no fragment.
@@ -752,12 +737,7 @@ IsSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm,
return false;
A_Base = FA->getAtom();
- if (!A_Base)
- return false;
-
B_Base = FB.getAtom();
- if (!B_Base)
- return false;
// If the atoms are the same, they are guaranteed to have the same address.
if (A_Base == B_Base)
@@ -922,7 +902,7 @@ void MachObjectWriter::WriteObject(MCAssembler &Asm,
sizeof(MachO::nlist_64) :
sizeof(MachO::nlist));
WriteSymtabLoadCommand(SymbolTableOffset, NumSymTabSymbols,
- StringTableOffset, StringTable.size());
+ StringTableOffset, StringTable.data().size());
WriteDysymtabLoadCommand(FirstLocalSymbol, NumLocalSymbols,
FirstExternalSymbol, NumExternalSymbols,
@@ -1028,7 +1008,7 @@ void MachObjectWriter::WriteObject(MCAssembler &Asm,
WriteNlist(UndefinedSymbolData[i], Layout);
// Write the string table.
- OS << StringTable.str();
+ OS << StringTable.data();
}
}
generated by cgit v1.1 at 2025-08-18 03:08:27 +0000