Initial implementation of a flow-graph builder for Dart's AST.

runtime/vm/compiler.cc

-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/compiler.h"
 
 #include "vm/assembler.h"
 #include "vm/ast_printer.h"
 #include "vm/code_generator.h"
 #include "vm/code_index_table.h"
 #include "vm/code_patcher.h"
 #include "vm/dart_entry.h"
 #include "vm/disassembler.h"
 #include "vm/exceptions.h"
 #include "vm/flags.h"
+#include "vm/flow_graph_builder.h"
 #include "vm/longjump.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
 #include "vm/opt_code_generator.h"
 #include "vm/os.h"
 #include "vm/parser.h"
 #include "vm/scanner.h"
 #include "vm/timer.h"
 
 namespace dart {
 
 DEFINE_FLAG(bool, disassemble, false, "Disassemble dart code.");
 DEFINE_FLAG(bool, trace_compiler, false, "Trace compiler operations.");
 DEFINE_FLAG(int, deoptimization_counter_threshold, 5,
     "How many times we allow deoptimization before we disallow"
     " certain optimizations");
+DEFINE_FLAG(bool, use_new_compiler, false,
+    "Try to use the new compiler backend.");
 
 
 // Compile a function. Should call only if the function has not been compiled.
 //   Arg0: function object.
 DEFINE_RUNTIME_ENTRY(CompileFunction, 1) {
   ASSERT(arguments.Count() == kCompileFunctionRuntimeEntry.argument_count());
   const Function& function = Function::CheckedHandle(arguments.At(0));
   ASSERT(!function.HasCode());
   const Error& error = Error::Handle(Compiler::CompileFunction(function));
   if (!error.IsNull()) {
@@ skipping 64 matching lines @@
     TIMERSCOPE(time_compilation);
     ParsedFunction parsed_function(function);
     const char* function_fullname = function.ToFullyQualifiedCString();
     if (FLAG_trace_compiler) {
       OS::Print("Compiling %sfunction: '%s' @ token %d\n",
                 (optimized ? "optimized " : ""),
                 function_fullname,
                 function.token_index());
     }
     Parser::ParseFunction(&parsed_function);
+    if (FLAG_use_new_compiler) {
+      FlowGraphBuilder graph_builder(parsed_function);
+      graph_builder.BuildGraph();
+      // Currently, always fails and falls through to the old compiler.
+    }
     CodeIndexTable* code_index_table = isolate->code_index_table();
     ASSERT(code_index_table != NULL);
     Assembler assembler;
     if (optimized) {
       // Transition to optimized code only from unoptimized code ... for now.
       ASSERT(function.HasCode());
       ASSERT(!Code::Handle(function.code()).is_optimized());
       // Do not use type feedback to optimize a function that was deoptimized.
       if (parsed_function.function().deoptimization_counter() <
           FLAG_deoptimization_counter_threshold) {
@@ skipping 207 matching lines @@
   } else {
     result = isolate->object_store()->sticky_error();
     isolate->object_store()->clear_sticky_error();
   }
   isolate->set_long_jump_base(base);
   return result.raw();
 }
 
 
 }  // namespace dart