Iterate over PcDescriptors only via iterators, not via an index. (preparation for more compression …

runtime/vm/simulator_arm.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include <math.h>  // for isnan.
 #include <setjmp.h>
 #include <stdlib.h>
 
 #include "vm/globals.h"
 #if defined(TARGET_ARCH_ARM)
@@ skipping 252 matching lines @@
   }
   return false;
 }
 
 
 intptr_t SimulatorDebugger::GetApproximateTokenIndex(const Code& code,
                                                      uword pc) {
   intptr_t token_pos = -1;
   const PcDescriptors& descriptors =
       PcDescriptors::Handle(code.pc_descriptors());
-  for (intptr_t i = 0; i < descriptors.Length(); i++) {
-    if (descriptors.PC(i) == pc) {
-      token_pos = descriptors.TokenPos(i);
-      break;
-    } else if ((token_pos <= 0) && (descriptors.PC(i) > pc)) {
-      token_pos = descriptors.TokenPos(i);
+  PcDescriptors::Iterator iter(descriptors);
+  while (iter.HasNext()) {
+    const RawPcDescriptors::PcDescriptorRec& rec = iter.Next();
+    if (rec.pc == pc) {
+      return rec.token_pos;
+    } else if ((token_pos <= 0) && (rec.pc > pc)) {
+      token_pos = rec.token_pos;
     }
   }
   return token_pos;
 }
 
 
 void SimulatorDebugger::PrintDartFrame(uword pc, uword fp, uword sp,
                                        const Function& function,
                                        intptr_t token_pos,
                                        bool is_optimized,
@@ skipping 3430 matching lines @@
   set_register(kExceptionObjectReg, bit_cast<int32_t>(raw_exception));
   set_register(kStackTraceObjectReg, bit_cast<int32_t>(raw_stacktrace));
   buf->Longjmp();
 }
 
 }  // namespace dart
 
 #endif  // !defined(HOST_ARCH_ARM)
 
 #endif  // defined TARGET_ARCH_ARM