Add script streaming API

src/compiler.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/v8.h"
 
 #include "src/compiler.h"
 
 #include "src/bootstrapper.h"
 #include "src/codegen.h"
@@ skipping 26 matching lines @@
   if (!IsAligned(reinterpret_cast<intptr_t>(data), kPointerAlignment)) {
     byte* copy = NewArray<byte>(length);
     DCHECK(IsAligned(reinterpret_cast<intptr_t>(copy), kPointerAlignment));
     CopyBytes(copy, data, length);
     data_ = copy;
     AcquireDataOwnership();
   }
 }
 
 
-CompilationInfo::CompilationInfo(Handle<Script> script,
-                                 Zone* zone)
+CompilationInfo::CompilationInfo(Handle<Script> script, Zone* zone)
     : flags_(StrictModeField::encode(SLOPPY)),
       script_(script),
+      source_stream_(NULL),
       osr_ast_id_(BailoutId::None()),
       parameter_count_(0),
       this_has_uses_(true),
       optimization_id_(-1),
       ast_value_factory_(NULL),
       ast_value_factory_owned_(false) {
   Initialize(script->GetIsolate(), BASE, zone);
 }
 
 
 CompilationInfo::CompilationInfo(Isolate* isolate, Zone* zone)
     : flags_(StrictModeField::encode(SLOPPY)),
       script_(Handle<Script>::null()),
       osr_ast_id_(BailoutId::None()),
       parameter_count_(0),
       this_has_uses_(true),
       optimization_id_(-1),
       ast_value_factory_(NULL),
       ast_value_factory_owned_(false) {
   Initialize(isolate, STUB, zone);
 }
 
 
 CompilationInfo::CompilationInfo(Handle<SharedFunctionInfo> shared_info,
                                  Zone* zone)
     : flags_(StrictModeField::encode(SLOPPY) | IsLazy::encode(true)),
       shared_info_(shared_info),
       script_(Handle<Script>(Script::cast(shared_info->script()))),
+      source_stream_(NULL),
       osr_ast_id_(BailoutId::None()),
       parameter_count_(0),
       this_has_uses_(true),
       optimization_id_(-1),
       ast_value_factory_(NULL),
       ast_value_factory_owned_(false) {
   Initialize(script_->GetIsolate(), BASE, zone);
 }
 
 
-CompilationInfo::CompilationInfo(Handle<JSFunction> closure,
-                                 Zone* zone)
+CompilationInfo::CompilationInfo(Handle<JSFunction> closure, Zone* zone)
     : flags_(StrictModeField::encode(SLOPPY) | IsLazy::encode(true)),
       closure_(closure),
       shared_info_(Handle<SharedFunctionInfo>(closure->shared())),
       script_(Handle<Script>(Script::cast(shared_info_->script()))),
+      source_stream_(NULL),
       context_(closure->context()),
       osr_ast_id_(BailoutId::None()),
       parameter_count_(0),
       this_has_uses_(true),
       optimization_id_(-1),
       ast_value_factory_(NULL),
       ast_value_factory_owned_(false) {
   Initialize(script_->GetIsolate(), BASE, zone);
 }
 
 
-CompilationInfo::CompilationInfo(HydrogenCodeStub* stub,
-                                 Isolate* isolate,
+CompilationInfo::CompilationInfo(HydrogenCodeStub* stub, Isolate* isolate,
                                  Zone* zone)
     : flags_(StrictModeField::encode(SLOPPY) | IsLazy::encode(true)),
+      source_stream_(NULL),
       osr_ast_id_(BailoutId::None()),
       parameter_count_(0),
       this_has_uses_(true),
       optimization_id_(-1),
       ast_value_factory_(NULL),
       ast_value_factory_owned_(false) {
   Initialize(isolate, STUB, zone);
   code_stub_ = stub;
 }
 
 
+CompilationInfo::CompilationInfo(ExternalSourceStream* stream, Isolate* isolate,
+                                 Zone* zone)
+    : flags_(StrictModeField::encode(SLOPPY)),
+      source_stream_(stream),
+      osr_ast_id_(BailoutId::None()),
+      parameter_count_(0),
+      this_has_uses_(true),
+      optimization_id_(-1),
+      ast_value_factory_(NULL),
+      ast_value_factory_owned_(false) {
+  Initialize(isolate, BASE, zone);
+}
+
+
 void CompilationInfo::Initialize(Isolate* isolate,
                                  Mode mode,
                                  Zone* zone) {
   isolate_ = isolate;
   function_ = NULL;
   scope_ = NULL;
   global_scope_ = NULL;
   extension_ = NULL;
   cached_data_ = NULL;
   compile_options_ = ScriptCompiler::kNoCompileOptions;
   zone_ = zone;
   deferred_handles_ = NULL;
   code_stub_ = NULL;
   prologue_offset_ = Code::kPrologueOffsetNotSet;
   opt_count_ = shared_info().is_null() ? 0 : shared_info()->opt_count();
   no_frame_ranges_ = isolate->cpu_profiler()->is_profiling()
                    ? new List<OffsetRange>(2) : NULL;
   for (int i = 0; i < DependentCode::kGroupCount; i++) {
     dependencies_[i] = NULL;
   }
   if (mode == STUB) {
     mode_ = STUB;
     return;
   }
   mode_ = mode;
   abort_due_to_dependency_ = false;
-  if (script_->type()->value() == Script::TYPE_NATIVE) MarkAsNative();
+  if (!script_.is_null() && script_->type()->value() == Script::TYPE_NATIVE) {
+    MarkAsNative();
+  }
   if (isolate_->debug()->is_active()) MarkAsDebug();
 
   if (!shared_info_.is_null()) {
     DCHECK(strict_mode() == SLOPPY);
     SetStrictMode(shared_info_->strict_mode());
   }
   set_bailout_reason(kUnknown);
 
   if (!shared_info().is_null() && shared_info()->is_compiled()) {
     // We should initialize the CompilationInfo feedback vector from the
@@ skipping 648 matching lines @@
   if (!CompileUnoptimizedCode(&info)) return;
   if (!info.shared_info().is_null()) {
     Handle<ScopeInfo> scope_info = ScopeInfo::Create(info.scope(),
                                                      info.zone());
     info.shared_info()->set_scope_info(*scope_info);
   }
   tracker.RecordRootFunctionInfo(info.code());
 }
 
 
-static bool DebuggerWantsEagerCompilation(CompilationInfo* info,
-                                          bool allow_lazy_without_ctx = false) {
-  return LiveEditFunctionTracker::IsActive(info->isolate()) ||
-         (info->isolate()->DebuggerHasBreakPoints() && !allow_lazy_without_ctx);
-}
-
-
 static Handle<SharedFunctionInfo> CompileToplevel(CompilationInfo* info) {
   Isolate* isolate = info->isolate();
   PostponeInterruptsScope postpone(isolate);
   DCHECK(!isolate->native_context().is_null());
   Handle<Script> script = info->script();
 
   // TODO(svenpanne) Obscure place for this, perhaps move to OnBeforeCompile?
   FixedArray* array = isolate->native_context()->embedder_data();
   script->set_context_data(array->get(0));
 
   isolate->debug()->OnBeforeCompile(script);
 
   DCHECK(info->is_eval() || info->is_global());
 
-  bool parse_allow_lazy =
-      (info->compile_options() == ScriptCompiler::kConsumeParserCache ||
-       String::cast(script->source())->length() > FLAG_min_preparse_length) &&
-      !DebuggerWantsEagerCompilation(info);
-
-  if (!parse_allow_lazy &&
-      (info->compile_options() == ScriptCompiler::kProduceParserCache ||
-       info->compile_options() == ScriptCompiler::kConsumeParserCache)) {
-    // We are going to parse eagerly, but we either 1) have cached data produced
-    // by lazy parsing or 2) are asked to generate cached data. We cannot use
-    // the existing data, since it won't contain all the symbols we need for
-    // eager parsing. In addition, it doesn't make sense to produce the data
-    // when parsing eagerly. That data would contain all symbols, but no
-    // functions, so it cannot be used to aid lazy parsing later.
-    info->SetCachedData(NULL, ScriptCompiler::kNoCompileOptions);
-  }
-
   Handle<SharedFunctionInfo> result;
 
   { VMState<COMPILER> state(info->isolate());
-    if (!Parser::Parse(info, parse_allow_lazy)) {
-      return Handle<SharedFunctionInfo>::null();
+    if (info->function() == NULL) {
+      // Parse the script if needed (if it's already parsed, function() returns
+      // non-NULL.
+      bool parse_allow_lazy =
+          (info->compile_options() == ScriptCompiler::kConsumeParserCache ||
+           String::cast(script->source())->length() >
+               FLAG_min_preparse_length) &&
+          !Compiler::DebuggerWantsEagerCompilation(info);
+
+      if (!parse_allow_lazy &&
+          (info->compile_options() == ScriptCompiler::kProduceParserCache ||
+           info->compile_options() == ScriptCompiler::kConsumeParserCache)) {
+        // We are going to parse eagerly, but we either 1) have cached data
+        // produced
+        // by lazy parsing or 2) are asked to generate cached data. We cannot
+        // use
+        // the existing data, since it won't contain all the symbols we need for
+        // eager parsing. In addition, it doesn't make sense to produce the data
+        // when parsing eagerly. That data would contain all symbols, but no
+        // functions, so it cannot be used to aid lazy parsing later.
+        info->SetCachedData(NULL, ScriptCompiler::kNoCompileOptions);
+      }
+      if (!Parser::Parse(info, parse_allow_lazy)) {
+        return Handle<SharedFunctionInfo>::null();
+      }
     }
 
     FunctionLiteral* lit = info->function();
     LiveEditFunctionTracker live_edit_tracker(isolate, lit);
 
     // Measure how long it takes to do the compilation; only take the
     // rest of the function into account to avoid overlap with the
     // parsing statistics.
     HistogramTimer* rate = info->is_eval()
           ? info->isolate()->counters()->compile_eval()
@@ skipping 26 matching lines @@
     PROFILE(isolate, CodeCreateEvent(
                 log_tag, *info->code(), *result, info, *script_name));
     GDBJIT(AddCode(script_name, script, info->code(), info));
 
     // Hint to the runtime system used when allocating space for initial
     // property space by setting the expected number of properties for
     // the instances of the function.
     SetExpectedNofPropertiesFromEstimate(result,
                                          lit->expected_property_count());
 
-    script->set_compilation_state(Script::COMPILATION_STATE_COMPILED);
+    if (!script.is_null())
+      script->set_compilation_state(Script::COMPILATION_STATE_COMPILED);
 
     live_edit_tracker.RecordFunctionInfo(result, lit, info->zone());
   }
 
   isolate->debug()->OnAfterCompile(script);
 
   return result;
 }
 
 
@@ skipping 136 matching lines @@
     }
 
     if (result.is_null()) isolate->ReportPendingMessages();
   } else if (result->ic_age() != isolate->heap()->global_ic_age()) {
     result->ResetForNewContext(isolate->heap()->global_ic_age());
   }
   return result;
 }
 
 
+Handle<SharedFunctionInfo> Compiler::CompileStreamedScript(
+    CompilationInfo* info, int source_length) {
+  Isolate* isolate = info->isolate();
+  isolate->counters()->total_load_size()->Increment(source_length);
+  isolate->counters()->total_compile_size()->Increment(source_length);
+
+  // TODO(marja): FLAG_use_strict is not honoured and won't be; when the real
+  // code caching lands, streaming needs to be adapted to use it.
+
+  if (FLAG_use_strict) info->SetStrictMode(STRICT);
+
+  Handle<SharedFunctionInfo> result = CompileToplevel(info);
+
+  if (result.is_null()) isolate->ReportPendingMessages();
+  return result;
+}
+
+
 Handle<SharedFunctionInfo> Compiler::BuildFunctionInfo(
     FunctionLiteral* literal, Handle<Script> script,
     CompilationInfo* outer_info) {
   // Precondition: code has been parsed and scopes have been analyzed.
   CompilationInfoWithZone info(script);
   info.SetFunction(literal);
   info.PrepareForCompilation(literal->scope());
   info.SetStrictMode(literal->scope()->strict_mode());
   if (outer_info->will_serialize()) info.PrepareForSerializing();
 
@@ skipping 279 matching lines @@
         log_tag, *code, *shared, info, script_name, line_num, column_num));
   }
 
   GDBJIT(AddCode(Handle<String>(shared->DebugName()),
                  Handle<Script>(info->script()),
                  Handle<Code>(info->code()),
                  info));
 }
 
 
+bool Compiler::DebuggerWantsEagerCompilation(CompilationInfo* info,
+                                             bool allow_lazy_without_ctx) {
+  return LiveEditFunctionTracker::IsActive(info->isolate()) ||
+         (info->isolate()->DebuggerHasBreakPoints() && !allow_lazy_without_ctx);
+}
+
+
 CompilationPhase::CompilationPhase(const char* name, CompilationInfo* info)
     : name_(name), info_(info), zone_(info->isolate()) {
   if (FLAG_hydrogen_stats) {
     info_zone_start_allocation_size_ = info->zone()->allocation_size();
     timer_.Start();
   }
 }
 
 
 CompilationPhase::~CompilationPhase() {
@@ skipping 11 matching lines @@
   AllowHandleDereference allow_deref;
   bool tracing_on = info()->IsStub()
       ? FLAG_trace_hydrogen_stubs
       : (FLAG_trace_hydrogen &&
          info()->closure()->PassesFilter(FLAG_trace_hydrogen_filter));
   return (tracing_on &&
       base::OS::StrChr(const_cast<char*>(FLAG_trace_phase), name_[0]) != NULL);
 }
 
 } }  // namespace v8::internal