[debugger] simplify compile for debugging.

src/debug/debug.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/debug/debug.h"
 
 #include <memory>
 
 #include "src/api.h"
 #include "src/arguments.h"
@@ skipping 1310 matching lines @@
       }
     }
   }
 
   // We do not need to replace code to debug bytecode.
   DCHECK(baseline_exists || functions.is_empty());
   DCHECK(baseline_exists || suspended_generators.is_empty());
 
   // We do not need to recompile to debug bytecode.
   if (baseline_exists && !shared->code()->has_debug_break_slots()) {
-    DCHECK(functions.length() > 0);
-    if (!Compiler::CompileDebugCode(functions.first())) return false;
+    if (!Compiler::CompileDebugCode(shared)) return false;
   }
 
   for (Handle<JSFunction> const function : functions) {
     function->ReplaceCode(shared->code());
     JSFunction::EnsureLiterals(function);
   }
 
   for (Handle<JSGeneratorObject> const generator_obj : suspended_generators) {
     int index = generator_obj->continuation();
     int pc_offset = ComputePcOffsetFromContinuationIndex(shared->code(), index);
@@ skipping 177 matching lines @@
         // function in order to create this shared function info. So there can
         // be no JSFunction referencing it. We can anticipate creating a debug
         // info while bypassing PrepareFunctionForBreakpoints.
         if (iteration > 1) {
           AllowHeapAllocation allow_before_return;
           CreateDebugInfo(shared_handle);
         }
         return shared_handle;
       }
     }
-    // If not, compile to reveal inner functions, if possible.
-    if (shared->allows_lazy_compilation()) {
-      HandleScope scope(isolate_);
-      if (!Compiler::CompileDebugCode(handle(shared))) break;
-      continue;
-    }
-
-    // If not possible, comb the heap for the best suitable compile target.
-    JSFunction* closure;
-    {
-      HeapIterator it(isolate_->heap());
-      SharedFunctionInfoFinder finder(position);
-      while (HeapObject* object = it.next()) {
-        JSFunction* candidate_closure = NULL;
-        SharedFunctionInfo* candidate = NULL;
-        if (object->IsJSFunction()) {
-          candidate_closure = JSFunction::cast(object);
-          candidate = candidate_closure->shared();
-        } else if (object->IsSharedFunctionInfo()) {
-          candidate = SharedFunctionInfo::cast(object);
-          if (!candidate->allows_lazy_compilation()) continue;
-        } else {
-          continue;
-        }
-        if (candidate->script() == *script) {
-          finder.NewCandidate(candidate, candidate_closure);
-        }
-      }
-      closure = finder.ResultClosure();
-      shared = finder.Result();
-    }
-    if (shared == NULL) break;
+    // If not, compile to reveal inner functions.
     HandleScope scope(isolate_);
-    if (closure == NULL) {
-      if (!Compiler::CompileDebugCode(handle(shared))) break;
-    } else {
-      if (!Compiler::CompileDebugCode(handle(closure))) break;
-    }
+    if (!Compiler::CompileDebugCode(handle(shared))) break;
   }
   return isolate_->factory()->undefined_value();
 }
 
 
 // Ensures the debug information is present for shared.
 bool Debug::EnsureDebugInfo(Handle<SharedFunctionInfo> shared,
                             Handle<JSFunction> function) {
   if (!shared->IsSubjectToDebugging()) return false;
 
@@ skipping 1067 matching lines @@
 }
 
 
 void LockingCommandMessageQueue::Clear() {
   base::LockGuard<base::Mutex> lock_guard(&mutex_);
   queue_.Clear();
 }
 
 }  // namespace internal
 }  // namespace v8