[Courgette] Using LabelManager to reduce Courgette-apply peak RAM by 25%.

courgette/rel32_finder_win32_x86.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <stdint.h>
 
 #include "courgette/rel32_finder_win32_x86.h"
 
 namespace courgette {
 
@@ skipping 69 matching lines @@
       RVA rel32_rva = static_cast<RVA>(rel32 - adjust_pointer_to_rva);
 
       // Is there an abs32 reloc overlapping the candidate?
       while (abs32_pos != abs32_locations.end() && *abs32_pos < rel32_rva - 3)
         ++abs32_pos;
       // Now: (*abs32_pos > rel32_rva - 4) i.e. the lowest addressed 4-byte
       // region that could overlap rel32_rva.
       if (abs32_pos != abs32_locations.end()) {
         if (*abs32_pos < rel32_rva + 4) {
           // Beginning of abs32 reloc is before end of rel32 reloc so they
-          // overlap.  Skip four bytes past the abs32 reloc.
+          // overlap. Skip four bytes past the abs32 reloc.
           p += (*abs32_pos + 4) - current_rva;
           continue;
         }
       }
 
+      // + 4 since offset is relative to start of next instruction.
       RVA target_rva = rel32_rva + 4 + Read32LittleEndian(rel32);
       // Valid, rel32 target must be within image, and within this section.
       // Subsumes |target_rva| != |kUnassignedRVA|.
       if (start_rva <= target_rva && target_rva < end_rva) {
         rel32_locations_.push_back(rel32_rva);
 #if COURGETTE_HISTOGRAM_TARGETS
         ++rel32_target_rvas_[target_rva];
 #endif
         p = rel32 + 4;
         continue;
       }
     }
     p += 1;
   }
 }
 
 }  // namespace courgette