Improve Code object support in service and observatory

runtime/vm/disassembler.cc

 // Copyright (c) 2011, 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/assembler.h"
 #include "vm/globals.h"
 #include "vm/os.h"
 #include "vm/json_stream.h"
@@ skipping 26 matching lines @@
   va_end(args);
 }
 
 
 void DisassembleToJSONStream::ConsumeInstruction(char* hex_buffer,
                                                  intptr_t hex_size,
                                                  char* human_buffer,
                                                  intptr_t human_size,
                                                  uword pc) {
   uint8_t* pc_ptr = reinterpret_cast<uint8_t*>(pc);
-  JSONObject jsobj(&jsarr_);
-  jsobj.AddProperty("type", "DisassembledInstruction");
-  jsobj.AddPropertyF("pc", "%p", pc_ptr);
-  jsobj.AddProperty("hex", hex_buffer);
-  jsobj.AddProperty("human", human_buffer);
+  // Instructions are represented as three consecutive values in a JSON array.
+  // All three are strings. The first is the address of the instruction,
+  // the second is the hex string of the code, and the final is a human
+  // readable string.
+  jsarr_.AddValueF("%p", pc_ptr);
+  jsarr_.AddValue(hex_buffer);
+  jsarr_.AddValue(human_buffer);
 }
 
 
 void DisassembleToJSONStream::Print(const char* format, ...) {
   va_list args;
   va_start(args, format);
   intptr_t len = OS::VSNPrint(NULL, 0, format, args);
   va_end(args);
   char* p = reinterpret_cast<char*>(malloc(len+1));
   va_start(args, format);
   intptr_t len2 = OS::VSNPrint(p, len, format, args);
   va_end(args);
   ASSERT(len == len2);
   for (intptr_t i = 0; i < len; i++) {
     if (p[i] == '\n' || p[i] == '\r') {
       p[i] = ' ';
     }
   }
-  JSONObject jsobj(&jsarr_);
-  jsobj.AddProperty("type", "DisassembledInstructionComment");
-  jsobj.AddProperty("comment", p);
+  // Instructions are represented as three consecutive values in a JSON array.
+  // All three are strings. Comments only use the third slot. See above comment
+  // for more information.
+  jsarr_.AddValue("");
+  jsarr_.AddValue("");
+  jsarr_.AddValue(p);
   free(p);
 }
 
 
 class FindAddrVisitor : public FindObjectVisitor {
    public:
     explicit FindAddrVisitor(uword addr)
         : FindObjectVisitor(Isolate::Current()), addr_(addr) { }
     virtual ~FindAddrVisitor() { }
 
@@ skipping 10 matching lines @@
     DISALLOW_COPY_AND_ASSIGN(FindAddrVisitor);
 };
 
 
 bool Disassembler::CanFindOldObject(uword addr) {
   FindAddrVisitor visitor(addr);
   return Isolate::Current()->heap()->FindOldObject(&visitor) != Object::null();
 }
 
 }  // namespace dart