[wasm] Use handles in wasm::GetDebugInfo.

src/frames.cc

 // Copyright 2012 the V8 project 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 "src/frames.h"
 
 #include <sstream>
 
 #include "src/ast/ast.h"
 #include "src/ast/scopeinfo.h"
@@ skipping 1415 matching lines @@
   DCHECK(deopt_data->length() == 2);
   return deopt_data->get(0);
 }
 
 uint32_t WasmFrame::function_index() const {
   FixedArray* deopt_data = LookupCode()->deoptimization_data();
   DCHECK(deopt_data->length() == 2);
   return Smi::cast(deopt_data->get(1))->value();
 }
 
 Script* WasmFrame::script() const {

[Michael Starzinger, 2016/07/08 08:05:07]

If {wasm::GetDebugInfo} can really trigger a GC then we will need to rework the
frame-walker to handlify this virtual method as well.

-  JSObject* wasm = JSObject::cast(wasm_obj());
-  Handle<wasm::WasmDebugInfo> debug_info(wasm::GetDebugInfo(wasm), isolate());
+  Handle<JSObject> wasm(JSObject::cast(wasm_obj()), isolate());
+  Handle<wasm::WasmDebugInfo> debug_info = wasm::GetDebugInfo(wasm);
   return wasm::WasmDebugInfo::GetFunctionScript(debug_info, function_index());
 }
 
 namespace {
 
 
 void PrintFunctionSource(StringStream* accumulator, SharedFunctionInfo* shared,
                          Code* code) {
   if (FLAG_max_stack_trace_source_length != 0 && code != NULL) {
     std::ostringstream os;
@@ skipping 420 matching lines @@
   for (StackFrameIterator it(isolate); !it.done(); it.Advance()) {
     StackFrame* frame = AllocateFrameCopy(it.frame(), zone);
     list.Add(frame, zone);
   }
   return list.ToVector();
 }
 
 
 }  // namespace internal
 }  // namespace v8