Subzero: Control memory growth from local label fixups.

src/IceELFSection.cpp

 //===- subzero/src/IceELFSection.cpp - Representation of ELF sections -----===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 49 matching lines @@
   if (AlignDiff == 0)
     return;
   if (Header.sh_type != llvm::ELF::SHT_NOBITS)
     Str.writeZeroPadding(AlignDiff);
   Header.sh_size += AlignDiff;
 }
 
 // Relocation sections.
 
 void ELFRelocationSection::addRelocations(RelocOffsetT BaseOff,
-                                          const FixupRefList &FixupRefs) {
+                                          const FixupRefList &FixupRefs,
+                                          ELFSymbolTableSection *SymTab) {
   for (const AssemblerFixup *FR : FixupRefs) {
     Fixups.push_back(*FR);
     AssemblerFixup &F = Fixups.back();
     F.set_position(BaseOff + F.position());
+    assert(!F.valueIsSymbol());
+    if (!F.isNullSymbol()) {
+      // Do an early lookup in the symbol table.  If the symbol is found,
+      // replace the Constant in the symbol with the ELFSym, and calculate the
+      // final value of the addend.  As such, a local label allocated from the
+      // Assembler arena will be converted to a symbol before the Assembler
+      // arena goes away.
+      if (const ELFSym *Sym = SymTab->findSymbol(F.symbol())) {
+        F.set_addend(F.offset());
+        F.set_value(Sym);
+      }
+    }
   }
 }
 
 size_t ELFRelocationSection::getSectionDataSize() const {
   return Fixups.size() * Header.sh_entsize;
 }
 
 // Symbol tables.
 
 void ELFSymbolTableSection::createNullSymbol(ELFSection *NullSection) {
@@ skipping 134 matching lines @@
       continue;
     }
     StringIndex.second = StringData.size();
     std::copy(Cur.begin(), Cur.end(), back_inserter(StringData));
     StringData.push_back(0);
     Prev = Cur;
   }
 }
 
 } // end of namespace Ice