Introduce a stack-allocated structure to encapsulate compile-time information.

src/compiler.cc

 // Copyright 2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 30 matching lines @@
 #include "usage-analyzer.h"
 
 namespace v8 {
 namespace internal {
 
 
 static Handle<Code> MakeCode(FunctionLiteral* literal,
                              Handle<Script> script,
                              Handle<Context> context,
                              bool is_eval,
-                             Handle<SharedFunctionInfo> shared,
-                             Handle<Object> receiver) {
+                             CompilationInfo* info) {
   ASSERT(literal != NULL);
 
   // Rewrite the AST by introducing .result assignments where needed.
   if (!Rewriter::Process(literal) || !AnalyzeVariableUsage(literal)) {
     // Signal a stack overflow by returning a null handle.  The stack
     // overflow exception will be thrown by the caller.
     return Handle<Code>::null();
   }
 
   {
@@ skipping 28 matching lines @@
   //  --full-compiler enables the dedicated backend for code we expect to be
   //    run once
   //  --fast-compiler enables a speculative optimizing backend (for
   //    non-run-once code)
   //
   // The normal choice of backend can be overridden with the flags
   // --always-full-compiler and --always-fast-compiler, which are mutually
   // incompatible.
   CHECK(!FLAG_always_full_compiler || !FLAG_always_fast_compiler);
 
+  Handle<SharedFunctionInfo> shared = info->shared_info();
   bool is_run_once = (shared.is_null())
       ? literal->scope()->is_global_scope()
       : (shared->is_toplevel() || shared->try_full_codegen());
 
   if (FLAG_always_full_compiler || (FLAG_full_compiler && is_run_once)) {
     FullCodeGenSyntaxChecker checker;
     checker.Check(literal);
     if (checker.has_supported_syntax()) {
       return FullCodeGenerator::MakeCode(literal, script, is_eval);
     }
   } else if (FLAG_always_fast_compiler ||
              (FLAG_fast_compiler && !is_run_once)) {
-    FastCodeGenSyntaxChecker checker(receiver);
-    checker.Check(literal);
+    FastCodeGenSyntaxChecker checker;
+    checker.Check(literal, info);
     if (checker.has_supported_syntax()) {
       AstLabeler labeler;
       labeler.Label(literal);
     }
     // Does not yet generate code.
   }
 
-  return CodeGenerator::MakeCode(literal, script, is_eval);
+  return CodeGenerator::MakeCode(literal, script, is_eval, info);
 }
 
 
 static bool IsValidJSON(FunctionLiteral* lit) {
   if (lit->body()->length() != 1)
     return false;
   Statement* stmt = lit->body()->at(0);
   if (stmt->AsExpressionStatement() == NULL)
     return false;
   Expression* expr = stmt->AsExpressionStatement()->expression();
@@ skipping 64 matching lines @@
 
   // 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 = is_eval
       ? &Counters::compile_eval
       : &Counters::compile;
   HistogramTimerScope timer(rate);
 
   // Compile the code.
-  Handle<Code> code = MakeCode(lit,
-                               script,
-                               context,
-                               is_eval,
-                               Handle<SharedFunctionInfo>::null(),
-                               Handle<Object>::null());  // No receiver.
+  CompilationInfo info(Handle<SharedFunctionInfo>::null(),
+                       Handle<Object>::null(),  // No receiver.
+                       0);  // Not nested in a loop.
+  Handle<Code> code = MakeCode(lit, script, context, is_eval, &info);
 
   // Check for stack-overflow exceptions.
   if (code.is_null()) {
     Top::StackOverflow();
     return Handle<JSFunction>::null();
   }
 
 #if defined ENABLE_LOGGING_AND_PROFILING || defined ENABLE_OPROFILE_AGENT
   // Log the code generation for the script. Check explicit whether logging is
   // to avoid allocating when not required.
@@ skipping 140 matching lines @@
       // For json it's unlikely that we'll ever see exactly the same
       // string again so we don't use the compilation cache.
       CompilationCache::PutEval(source, context, is_global, result);
     }
   }
 
   return result;
 }
 
 
-bool Compiler::CompileLazy(Handle<SharedFunctionInfo> shared,
-                           Handle<Object> receiver,
-                           int loop_nesting) {
+bool Compiler::CompileLazy(CompilationInfo* info) {
   CompilationZoneScope zone_scope(DELETE_ON_EXIT);
 
   // The VM is in the COMPILER state until exiting this function.
   VMState state(COMPILER);
 
   PostponeInterruptsScope postpone;
 
   // Compute name, source code and script data.
+  Handle<SharedFunctionInfo> shared = info->shared_info();
   Handle<String> name(String::cast(shared->name()));
   Handle<Script> script(Script::cast(shared->script()));
 
   int start_position = shared->start_position();
   int end_position = shared->end_position();
   bool is_expression = shared->is_expression();
   Counters::total_compile_size.Increment(end_position - start_position);
 
   // Generate the AST for the lazily compiled function. The AST may be
   // NULL in case of parser stack overflow.
   FunctionLiteral* lit = MakeLazyAST(script, name,
                                      start_position,
                                      end_position,
                                      is_expression);
 
   // Check for parse errors.
   if (lit == NULL) {
     ASSERT(Top::has_pending_exception());
     return false;
   }
 
-  // Update the loop nesting in the function literal.
-  lit->set_loop_nesting(loop_nesting);
-
   // Measure how long it takes to do the lazy compilation; only take
   // the rest of the function into account to avoid overlap with the
   // lazy parsing statistics.
   HistogramTimerScope timer(&Counters::compile_lazy);
 
   // Compile the code.
   Handle<Code> code = MakeCode(lit,
                                script,
                                Handle<Context>::null(),
                                false,
-                               shared,
-                               receiver);
+                               info);
 
   // Check for stack-overflow exception.
   if (code.is_null()) {
     Top::StackOverflow();
     return false;
   }
 
 #if defined ENABLE_LOGGING_AND_PROFILING || defined ENABLE_OPROFILE_AGENT
   // Log the code generation. If source information is available include script
   // name and line number. Check explicit whether logging is enabled as finding
@@ skipping 60 matching lines @@
   } else {
     // The bodies of function literals have not yet been visited by
     // the AST optimizer/analyzer.
     if (!Rewriter::Optimize(literal)) {
       return Handle<JSFunction>::null();
     }
 
     // Generate code and return it.  The way that the compilation mode
     // is controlled by the command-line flags is described in
     // the static helper function MakeCode.
+    CompilationInfo info(Handle<SharedFunctionInfo>::null(),
+                         Handle<Object>::null(),  // No receiver.
+                         0);  // Not nested in a loop.
+
     CHECK(!FLAG_always_full_compiler || !FLAG_always_fast_compiler);
     bool is_run_once = literal->try_full_codegen();
     bool is_compiled = false;
     if (FLAG_always_full_compiler || (FLAG_full_compiler && is_run_once)) {
       FullCodeGenSyntaxChecker checker;
       checker.Check(literal);
       if (checker.has_supported_syntax()) {
         code = FullCodeGenerator::MakeCode(literal,
                                            script,
                                            false);  // Not eval.
         is_compiled = true;
       }
     } else if (FLAG_always_fast_compiler ||
                (FLAG_fast_compiler && !is_run_once)) {
       // Since we are not lazily compiling we do not have a receiver to
       // specialize for.
-      FastCodeGenSyntaxChecker checker(Handle<Object>::null());
-      checker.Check(literal);
+      FastCodeGenSyntaxChecker checker;
+      checker.Check(literal, &info);
       if (checker.has_supported_syntax()) {
         AstLabeler label_nodes;
         label_nodes.Label(literal);
       }
       // Generate no code.
     }
 
     if (!is_compiled) {
       // We fall back to the classic V8 code generator.
       code = CodeGenerator::MakeCode(literal,
                                      script,
-                                     false);  // Not eval.
+                                     false,  // Not eval.
+                                     &info);
     }
 
     // Check for stack-overflow exception.
     if (code.is_null()) {
       caller->SetStackOverflow();
       return Handle<JSFunction>::null();
     }
 
     // Function compilation complete.
     LOG(CodeCreateEvent(Logger::FUNCTION_TAG, *code, *literal->name()));
@@ skipping 43 matching lines @@
   fun->shared()->set_is_toplevel(is_toplevel);
   fun->shared()->set_inferred_name(*lit->inferred_name());
   fun->shared()->SetThisPropertyAssignmentsInfo(
       lit->has_only_simple_this_property_assignments(),
       *lit->this_property_assignments());
   fun->shared()->set_try_full_codegen(lit->try_full_codegen());
 }
 
 
 } }  // namespace v8::internal