Keep a canonical list of shared function infos.

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/compiler.h"
 
 #include <algorithm>
 
 #include "src/ast-numbering.h"
 #include "src/bootstrapper.h"
@@ skipping 995 matching lines @@
 
 
 void Compiler::CompileForLiveEdit(Handle<Script> script) {
   // TODO(635): support extensions.
   Zone zone;
   ParseInfo parse_info(&zone, script);
   CompilationInfo info(&parse_info);
   PostponeInterruptsScope postpone(info.isolate());
   VMState<COMPILER> state(info.isolate());
 
+  // Get rid of old list of shared function infos.
+  script->set_shared_function_infos(Smi::FromInt(0));
+
   info.parse_info()->set_global();
   if (!Parser::ParseStatic(info.parse_info())) return;
 
   LiveEditFunctionTracker tracker(info.isolate(), info.function());
   if (!CompileUnoptimizedCode(&info)) return;
   if (info.has_shared_info()) {
     Handle<ScopeInfo> scope_info =
         ScopeInfo::Create(info.isolate(), info.zone(), info.scope());
     info.shared_info()->set_scope_info(*scope_info);
   }
@@ skipping 66 matching lines @@
     // Allocate function.
     DCHECK(!info->code().is_null());
     result = isolate->factory()->NewSharedFunctionInfo(
         lit->name(), lit->materialized_literal_count(), lit->kind(),
         info->code(),
         ScopeInfo::Create(info->isolate(), info->zone(), info->scope()),
         info->feedback_vector());
 
     DCHECK_EQ(RelocInfo::kNoPosition, lit->function_token_position());
     SharedFunctionInfo::InitFromFunctionLiteral(result, lit);
-    result->set_script(*script);
+    SharedFunctionInfo::SetScript(result, script);
     result->set_is_toplevel(true);
 
     Handle<String> script_name = script->name()->IsString()
         ? Handle<String>(String::cast(script->name()))
         : isolate->factory()->empty_string();
     Logger::LogEventsAndTags log_tag = info->is_eval()
         ? Logger::EVAL_TAG
         : Logger::ToNativeByScript(Logger::SCRIPT_TAG, *script);
 
     PROFILE(isolate, CodeCreateEvent(
@@ skipping 212 matching lines @@
   parse_info->set_language_mode(
       static_cast<LanguageMode>(parse_info->language_mode() | language_mode));
 
   CompilationInfo compile_info(parse_info);
   // TODO(marja): FLAG_serialize_toplevel is not honoured and won't be; when the
   // real code caching lands, streaming needs to be adapted to use it.
   return CompileToplevel(&compile_info);
 }
 
 
-Handle<SharedFunctionInfo> Compiler::BuildFunctionInfo(
+Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfo(
     FunctionLiteral* literal, Handle<Script> script,
     CompilationInfo* outer_info) {
   // Precondition: code has been parsed and scopes have been analyzed.
+  MaybeHandle<SharedFunctionInfo> maybe_existing =
+      script->FindSharedFunctionInfo(literal);
+  // We found an existing shared function info. If it's already compiled,
+  // don't worry about compiling it, and simply return it. If it's not yet
+  // compiled, continue to decide whether to eagerly compile.
+  Handle<SharedFunctionInfo> existing;
+  if (maybe_existing.ToHandle(&existing) && existing->is_compiled()) {
+    return existing;
+  }
+
   Zone zone;
   ParseInfo parse_info(&zone, script);
   CompilationInfo info(&parse_info);
   parse_info.set_literal(literal);
   parse_info.set_scope(literal->scope());
   parse_info.set_language_mode(literal->scope()->language_mode());
   if (outer_info->will_serialize()) info.PrepareForSerializing();
 
   Isolate* isolate = info.isolate();
   Factory* factory = isolate->factory();
@@ skipping 40 matching lines @@
     DCHECK(!info.code().is_null());
     scope_info = ScopeInfo::Create(info.isolate(), info.zone(), info.scope());
     if (literal->should_eager_compile() &&
         literal->should_be_used_once_hint()) {
       info.code()->MarkToBeExecutedOnce(isolate);
     }
   } else {
     return Handle<SharedFunctionInfo>::null();
   }
 
-  // Create a shared function info object.
-  Handle<SharedFunctionInfo> result = factory->NewSharedFunctionInfo(
-      literal->name(), literal->materialized_literal_count(), literal->kind(),
-      info.code(), scope_info, info.feedback_vector());
+  if (maybe_existing.is_null()) {
+    // Create a shared function info object.
+    Handle<SharedFunctionInfo> result = factory->NewSharedFunctionInfo(
+        literal->name(), literal->materialized_literal_count(), literal->kind(),
+        info.code(), scope_info, info.feedback_vector());
 
-  SharedFunctionInfo::InitFromFunctionLiteral(result, literal);
-  result->set_script(*script);
-  result->set_is_toplevel(false);
+    SharedFunctionInfo::InitFromFunctionLiteral(result, literal);
+    SharedFunctionInfo::SetScript(result, script);
+    result->set_is_toplevel(false);
 
-  RecordFunctionCompilation(Logger::FUNCTION_TAG, &info, result);
-  result->set_allows_lazy_compilation(literal->AllowsLazyCompilation());
-  result->set_allows_lazy_compilation_without_context(allow_lazy_without_ctx);
+    RecordFunctionCompilation(Logger::FUNCTION_TAG, &info, result);
+    result->set_allows_lazy_compilation(literal->AllowsLazyCompilation());
+    result->set_allows_lazy_compilation_without_context(allow_lazy_without_ctx);
 
-  // Set the expected number of properties for instances and return
-  // the resulting function.
-  SetExpectedNofPropertiesFromEstimate(result,
-                                       literal->expected_property_count());
-  live_edit_tracker.RecordFunctionInfo(result, literal, info.zone());
-  return result;
+    // Set the expected number of properties for instances and return
+    // the resulting function.
+    SetExpectedNofPropertiesFromEstimate(result,
+                                         literal->expected_property_count());
+    live_edit_tracker.RecordFunctionInfo(result, literal, info.zone());
+    return result;
+  } else {
+    // We may have additional data from compilation now.
+    DCHECK(!existing->is_compiled());
+    existing->ReplaceCode(*info.code());
+    existing->set_scope_info(*scope_info);
+    existing->set_feedback_vector(*info.feedback_vector());
+    return existing;
+  }
 }
 
 
 MaybeHandle<Code> Compiler::GetOptimizedCode(Handle<JSFunction> function,
                                              Handle<Code> current_code,
                                              ConcurrencyMode mode,
                                              BailoutId osr_ast_id) {
   Handle<Code> cached_code;
   if (GetCodeFromOptimizedCodeMap(
           function, osr_ast_id).ToHandle(&cached_code)) {
@@ skipping 140 matching lines @@
 
 
 #if DEBUG
 void CompilationInfo::PrintAstForTesting() {
   PrintF("--- Source from AST ---\n%s\n",
          PrettyPrinter(isolate(), zone()).PrintProgram(function()));
 }
 #endif
 }  // namespace internal
 }  // namespace v8