[wasm] Enable wasm frame inspection for debugging

src/debug/debug-frames.cc

Index: src/debug/debug-frames.cc
diff --git a/src/debug/debug-frames.cc b/src/debug/debug-frames.cc
index b1a8af256934d3e5d8ba93c49a9bce0d7c5e8d62..a0dd91d466cbc83f0649efe6c668dbeb04212115 100644
--- a/src/debug/debug-frames.cc
+++ b/src/debug/debug-frames.cc
@@ -5,29 +5,35 @@
 #include "src/debug/debug-frames.h"
 
 #include "src/frames-inl.h"
+#include "src/wasm/wasm-debug.h"
+#include "src/wasm/wasm-module.h"
 
 namespace v8 {
 namespace internal {
 
-FrameInspector::FrameInspector(JavaScriptFrame* frame,
-                               int inlined_jsframe_index, Isolate* isolate)
+FrameInspector::FrameInspector(StandardFrame* frame, int inlined_jsframe_index,
+                               Isolate* isolate)
     : frame_(frame), deoptimized_frame_(NULL), isolate_(isolate) {
-  has_adapted_arguments_ = frame_->has_adapted_arguments();
+  JavaScriptFrame* js_frame =
+      frame->is_java_script() ? javascript_frame() : nullptr;
+  DCHECK(js_frame || frame->is_wasm());
+  has_adapted_arguments_ = js_frame && js_frame->has_adapted_arguments();
   is_bottommost_ = inlined_jsframe_index == 0;
   is_optimized_ = frame_->is_optimized();
   is_interpreted_ = frame_->is_interpreted();
   // Calculate the deoptimized frame.
   if (frame->is_optimized()) {
+    DCHECK(js_frame != nullptr);
     // TODO(turbofan): Revisit once we support deoptimization.
-    if (frame->LookupCode()->is_turbofanned() &&
-        frame->function()->shared()->asm_function() &&
+    if (js_frame->LookupCode()->is_turbofanned() &&
+        js_frame->function()->shared()->asm_function() &&
         !FLAG_turbo_asm_deoptimization) {
       is_optimized_ = false;
       return;
     }
 
     deoptimized_frame_ = Deoptimizer::DebuggerInspectableFrame(
-        frame, inlined_jsframe_index, isolate);
+        js_frame, inlined_jsframe_index, isolate);
   }
 }
 
@@ -41,29 +47,56 @@ FrameInspector::~FrameInspector() {
 
 
 int FrameInspector::GetParametersCount() {
-  return is_optimized_ ? deoptimized_frame_->parameters_count()
-                       : frame_->ComputeParametersCount();
+  if (is_optimized_) return deoptimized_frame_->parameters_count();
+  if (frame_->is_wasm()) {
+    // TODO(clemensh): return real parameter count
+    return 0;
+  }
+  return javascript_frame()->ComputeParametersCount();

[Yang, 2016/06/16 14:10:41]

Can we make ComputeParameterCount a virtual method on StandardFrame that returns
0 for wasm frames?

[Clemens Hammacher, 2016/06/16 17:02:30]

Done.

+}
+
+Handle<Script> FrameInspector::GetScript() {
+  if (frame_->is_wasm()) {
+    DCHECK(wasm_frame()->wasm_obj()->IsJSObject());

[Yang, 2016/06/16 14:10:41]

I wish we don't have to check against is_wasm everywhere. Can't we simply have
GetFunction return the correct function wrapper for the wasm code, from which we
can then get its SharedFunctionInfo and script?

[Clemens Hammacher, 2016/06/16 17:02:30]

We don't have a JSFunction for wasm frames, that's why we need to get the script
otherwise. But I pulled the script accessor up to the standard frame.

+    JSObject* wasm_obj = JSObject::cast(wasm_frame()->wasm_obj());
+    int func_index = wasm_frame()->function_index();
+    return handle(wasm::GetDebugInfo(wasm_obj)->GetFunctionScript(func_index),
+                  isolate_);
+  }
+  return handle(Script::cast(GetFunction()->shared()->script()), isolate_);
 }
 
-Handle<Object> FrameInspector::GetFunction() {
+Handle<JSFunction> FrameInspector::GetFunction() {
+  DCHECK(!frame_->is_wasm());
   return is_optimized_ ? deoptimized_frame_->GetFunction()
-                       : handle(frame_->function(), isolate_);
+                       : handle(javascript_frame()->function(), isolate_);
 }
 
 Handle<Object> FrameInspector::GetParameter(int index) {
-  return is_optimized_ ? deoptimized_frame_->GetParameter(index)
-                       : handle(frame_->GetParameter(index), isolate_);
+  if (is_optimized_) return deoptimized_frame_->GetParameter(index);
+  if (frame_->is_wasm()) {
+    // TODO(clemensh): return real parameter value for debugged frame
+    return isolate_->factory()->undefined_value();
+  }
+  return handle(javascript_frame()->GetParameter(index), isolate_);

[Yang, 2016/06/16 14:10:41]

Same here. GetParameter could be a virtual method on StandardFrame.

[Clemens Hammacher, 2016/06/16 17:02:30]

Done.

 }
 
 Handle<Object> FrameInspector::GetExpression(int index) {
+  if (frame_->is_wasm()) {
+    // TODO(clemensh): find out what this function does, and whether we can do
+    // anything for wasm
+    return isolate_->factory()->undefined_value();
+  }
+
+  JavaScriptFrame* js_frame = javascript_frame();
   // TODO(turbofan): Revisit once we support deoptimization.
-  if (frame_->LookupCode()->is_turbofanned() &&
-      frame_->function()->shared()->asm_function() &&
+  if (js_frame->LookupCode()->is_turbofanned() &&
+      js_frame->function()->shared()->asm_function() &&
       !FLAG_turbo_asm_deoptimization) {
     return isolate_->factory()->undefined_value();
   }
   return is_optimized_ ? deoptimized_frame_->GetExpression(index)
-                       : handle(frame_->GetExpression(index), isolate_);
+                       : handle(js_frame->GetExpression(index), isolate_);
 }
 
 
@@ -83,21 +116,24 @@ int FrameInspector::GetSourcePosition() {
 
 
 bool FrameInspector::IsConstructor() {
+  if (frame_->is_wasm()) return false;
   return is_optimized_ && !is_bottommost_
              ? deoptimized_frame_->HasConstructStub()
-             : frame_->IsConstructor();
+             : javascript_frame()->IsConstructor();

[Yang, 2016/06/16 14:10:41]

Same here.

[Clemens Hammacher, 2016/06/16 17:02:31]

Done.

 }
 
 Handle<Object> FrameInspector::GetContext() {
-  return is_optimized_ ? deoptimized_frame_->GetContext()
-                       : handle(frame_->context(), isolate_);
+  if (frame_->is_wasm()) return isolate_->factory()->undefined_value();
+  if (is_optimized_) return deoptimized_frame_->GetContext();
+  return handle(javascript_frame()->context(), isolate_);

[Yang, 2016/06/16 14:10:41]

And here.

[Clemens Hammacher, 2016/06/16 17:02:30]

Done.

 }
 
 
 // To inspect all the provided arguments the frame might need to be
 // replaced with the arguments frame.
-void FrameInspector::SetArgumentsFrame(JavaScriptFrame* frame) {
+void FrameInspector::SetArgumentsFrame(StandardFrame* frame) {
   DCHECK(has_adapted_arguments_);
+  DCHECK(frame->is_arguments_adaptor());
   frame_ = frame;
   is_optimized_ = frame_->is_optimized();
   is_interpreted_ = frame_->is_interpreted();
@@ -156,10 +192,8 @@ void FrameInspector::MaterializeStackLocals(Handle<JSObject> target,
 
 void FrameInspector::UpdateStackLocalsFromMaterializedObject(
     Handle<JSObject> target, Handle<ScopeInfo> scope_info) {
-  if (is_optimized_) {
-    // Optimized frames are not supported. Simply give up.
-    return;
-  }
+  // Optimized frames and wasm frames are not supported. Simply give up.
+  if (is_optimized_ || frame_->is_wasm()) return;
 
   HandleScope scope(isolate_);
 
@@ -170,10 +204,10 @@ void FrameInspector::UpdateStackLocalsFromMaterializedObject(
     if (ScopeInfo::VariableIsSynthetic(*name)) continue;
     if (ParameterIsShadowedByContextLocal(scope_info, name)) continue;
 
-    DCHECK(!frame_->GetParameter(i)->IsTheHole(isolate_));
+    DCHECK(!javascript_frame()->GetParameter(i)->IsTheHole(isolate_));
     Handle<Object> value =
         Object::GetPropertyOrElement(target, name).ToHandleChecked();
-    frame_->SetParameterValue(i, *value);
+    javascript_frame()->SetParameterValue(i, *value);
   }
 
   // Stack locals.
@@ -198,9 +232,8 @@ bool FrameInspector::ParameterIsShadowedByContextLocal(
                                      &maybe_assigned_flag) != -1;
 }
 
-
-SaveContext* DebugFrameHelper::FindSavedContextForFrame(
-    Isolate* isolate, JavaScriptFrame* frame) {
+SaveContext* DebugFrameHelper::FindSavedContextForFrame(Isolate* isolate,
+                                                        StandardFrame* frame) {
   SaveContext* save = isolate->save_context();
   while (save != NULL && !save->IsBelowFrame(frame)) {
     save = save->prev();
@@ -209,13 +242,16 @@ SaveContext* DebugFrameHelper::FindSavedContextForFrame(
   return save;
 }
 
-
-int DebugFrameHelper::FindIndexedNonNativeFrame(JavaScriptFrameIterator* it,
+int DebugFrameHelper::FindIndexedNonNativeFrame(StackTraceFrameIterator* it,
                                                 int index) {
   int count = -1;
   for (; !it->done(); it->Advance()) {
+    if (it->is_wasm()) {
+      if (++count == index) return 0;
+      continue;
+    }
     List<FrameSummary> frames(FLAG_max_inlining_levels + 1);
-    it->frame()->Summarize(&frames);
+    it->javascript_frame()->Summarize(&frames);
     for (int i = frames.length() - 1; i >= 0; i--) {
       // Omit functions from native and extension scripts.
       if (!frames[i].function()->shared()->IsSubjectToDebugging()) continue;