`9dbf0eb`

Cache rebase symbol lookups

Authored by mfwolffe <wolffemf@dukes.jmu.edu> 3 weeks ago

SHA: 9dbf0eb3a8e185ceb59830ed53990ce9b3ca8da3
Parents: 86f5fa3
Tree: 6bdc462

1 changed file

Status	File	+	-
M	`src/macho/writer.rs`	23	8

src/macho/writer.rsmodified

          .iter()
          .map(|input| (input.id, input.object))
          .collect();
 +    let symbol_name_index = build_symbol_name_index(inputs.0.sym_table);
      for section in &layout.sections {
          if !matches!(section.segment.as_str(), "__DATA" | "__DATA_CONST") {
                  .map(Vec::as_slice)
                  .unwrap_or(&[]);
              for reloc in relocs_for_rebase(relocs, atom) {
 -                if !reloc_needs_rebase(obj, reloc, inputs.0.sym_table) {
 +                if !reloc_needs_rebase(obj, reloc, inputs.0.sym_table, &symbol_name_index) {
                      continue;
+                 }
                  let local_offset = reloc.offset.saturating_sub(atom.input_offset) as u64;
      })
+ }
 -fn reloc_needs_rebase(obj: &ObjectFile, reloc: Reloc, sym_table: &SymbolTable) -> bool {
 +fn reloc_needs_rebase(
 +    obj: &ObjectFile,
 +    reloc: Reloc,
 +    sym_table: &SymbolTable,
 +    symbol_name_index: &HashMap<String, SymbolId>,
 +) -> bool {
      if reloc.kind != RelocKind::Unsigned
          || reloc.length != RelocLength::Quad
          || reloc.pcrel
              let Some(input_sym) = obj.symbols.get(sym_idx as usize) else {
                  return false;
              };
 -            match symbol_referent_id(obj, reloc.referent, sym_table) {
 +            match symbol_referent_id(obj, reloc.referent, symbol_name_index) {
                  Some(symbol_id) => match sym_table.get(symbol_id) {
                      Symbol::DylibImport { .. } => false,
                      Symbol::Defined { atom, .. } => atom.0 != 0,
+     }
+ }
 +fn build_symbol_name_index(sym_table: &SymbolTable) -> HashMap<String, SymbolId> {
 +    sym_table
 +        .iter()
 +        .map(|(symbol_id, symbol)| {
 +            (
 +                sym_table.interner.resolve(symbol.name()).to_string(),
 +                symbol_id,
 +            )
 +        })
 +        .collect()
 +}
++
  fn symbol_referent_id(
      obj: &ObjectFile,
      referent: Referent,
 -    sym_table: &SymbolTable,
 +    symbol_name_index: &HashMap<String, SymbolId>,
  ) -> Option<SymbolId> {
      let Referent::Symbol(sym_idx) = referent else {
          return None;
      };
      let input_sym = obj.symbols.get(sym_idx as usize)?;
      let name = obj.symbol_name(input_sym).ok()?;
 -    let (symbol_id, _) = sym_table
 -        .iter()
 -        .find(|(_, symbol)| sym_table.interner.resolve(symbol.name()) == name)?;
 -    Some(symbol_id)
 +    symbol_name_index.get(name).copied()
+ }
  fn build_function_starts(