Add enough compiler support to compile empty functions on x64.

runtime/vm/compiler.cc

 // 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/flow_graph_compiler.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 {
@@ skipping 88 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) {

[srdjan, 2012/02/24 23:13:02]

ASSERT(!optimized).

[Kevin Millikin (Google), 2012/02/27 08:22:07]

Done.

       LongJump* old_base = isolate->long_jump_base();
       LongJump bailout_jump;
       isolate->set_long_jump_base(&bailout_jump);
       if (setjmp(*bailout_jump.Set()) == 0) {
         FlowGraphBuilder graph_builder(parsed_function);
         graph_builder.BuildGraph();
+
+        // Try to compile on x64 (only for now).
+#ifdef TARGET_ARCH_X64
+        Assembler assembler;
+        FlowGraphCompiler graph_compiler(&assembler,
+                                         parsed_function,
+                                         graph_builder.blocks());
+        graph_compiler.CompileGraph();

[srdjan, 2012/02/24 23:13:02]

It would be better to implement "dummy" FlowGraphCompiler in _ia32 and simarm.
This can happen in a later CL (please add a TODO).

[Kevin Millikin (Google), 2012/02/27 08:22:07]

Agreed.  Done.

+#endif
+
       } else {
         // We bailed out.
         Error& bailout_error = Error::Handle(
             isolate->object_store()->sticky_error());
         isolate->object_store()->clear_sticky_error();
         if (FLAG_trace_bailout) {
           OS::Print("%s\n", bailout_error.ToErrorCString());
         }
       }
       isolate->set_long_jump_base(old_base);
@@ skipping 219 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