Use a breakpoint instruction for a stop message on arm instead of

runtime/vm/disassembler_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 "vm/disassembler.h"
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_ARM.
 #if defined(TARGET_ARCH_ARM)
 
 #include "platform/assert.h"
@@ skipping 665 matching lines @@
             Format(instr, "blx'cond 'rm");
           } else {
             // Could be inlined constant.
             Unknown(instr);
           }
           break;
         }
         case 7: {
           if ((instr->Bits(21, 2) == 0x1) && (instr->ConditionField() == AL)) {
             Format(instr, "bkpt #'imm12_4");
+            if (instr->BkptField() == Instr::kStopMessageCode) {
+              const char* message = *reinterpret_cast<const char**>(
+                  reinterpret_cast<intptr_t>(instr) - Instr::kInstrSize);
+              buffer_pos_ += OS::SNPrint(current_position_in_buffer(),
+                                         remaining_size_in_buffer(),
+                                         " ; \"%s\"",
+                                         message);
+            }
           } else {
              // Format(instr, "smc'cond");
             Unknown(instr);  // Not used.
           }
           break;
         }
         default: {
           Unknown(instr);  // Not used.
           break;
         }
@@ skipping 397 matching lines @@
     }
   } else {
     Unknown(instr);
   }
 }
 
 
 void ARMDecoder::DecodeType7(Instr* instr) {
   if (instr->Bit(24) == 1) {
     Format(instr, "svc'cond #'svc");
-    if (instr->SvcField() == kStopMessageSvcCode) {
-      const char* message = *reinterpret_cast<const char**>(
-          reinterpret_cast<intptr_t>(instr) - Instr::kInstrSize);
-      buffer_pos_ += OS::SNPrint(current_position_in_buffer(),
-                                 remaining_size_in_buffer(),
-                                 " ; \"%s\"",
-                                 message);
-    }
   } else if (instr->IsVFPDataProcessingOrSingleTransfer()) {
     if (instr->Bit(4) == 0) {
       // VFP Data Processing
       switch (instr->Bits(20, 4) & 0xb) {
         case 0: {  // vmla, vmls floating-point
           if (instr->Bit(8) == 0) {
             if (instr->Bit(6) == 0) {
               Format(instr, "vmlas'cond 'sd, 'sn, 'sm");
             } else {
               Format(instr, "vmlss'cond 'sd, 'sn, 'sm");
@@ skipping 410 matching lines @@
   int32_t instruction_bits = Instr::At(pc)->InstructionBits();
   OS::SNPrint(hex_buffer, hex_size, "%08x", instruction_bits);
   if (out_instr_size) {
     *out_instr_size = Instr::kInstrSize;
   }
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM