provides a mechanism for optimizing compilers to select the different Register configuration.

src/register-configuration.h

Index: src/register-configuration.h
diff --git a/src/register-configuration.h b/src/register-configuration.h
index f12bc7c07c6dfb4beb79477f5a88ce16502b4c71..9d1c76f137c93502fb63ce122379c6c425ccc9d3 100644
--- a/src/register-configuration.h
+++ b/src/register-configuration.h
@@ -20,6 +20,8 @@ class RegisterConfiguration {
 
   static const RegisterConfiguration* ArchDefault();

[danno, 2015/10/16 08:47:02]

I would prefer to have a single ArchDefault call that has a enum { CRANKSHAFT,
TURBOFAN } parameter that returns one or the other configurations.

 
+  static const RegisterConfiguration* ArchDefaultForTurbo();
+
   RegisterConfiguration(int num_general_registers, int num_double_registers,
                         int num_allocatable_general_registers,
                         int num_allocatable_double_registers,