Optional arguments in new compiler.

Optional arguments in new compiler.
Includes Issue 9664062: Support allocating and calling closures in the new non-optimizing compiler (with fixes)
Committed: https://code.google.com/p/dart/source/detail?r=5419

[Kevin Millikin (Google), 2012-03-13 12:31:07]

LGTM with the change below addressed one way or another.  I don't care too much
whether stack_local_count includes copied parameters or not.

That is, also assuming there is nothing interesting to be aware of in the
duplicated code.

https://chromiumcodereview.appspot.com/9693020/diff/2019/runtime/vm/code_gene...
File runtime/vm/code_generator_ia32.cc (right):

https://chromiumcodereview.appspot.com/9693020/diff/2019/runtime/vm/code_gene...
runtime/vm/code_generator_ia32.cc:574: const int base =
parsed_function_.first_local_index();
I think with your change to make local_count() include the number of copied
parameters, you will want something like:

const int base = parsed_function_.first_local_index();
const int count =
  parsed_function_.local_count() - parsed_function_.copied_parameter_count();
for (int index = 0; index < count; ++index) ...

Otherwise we're needlessly initializing above the stack pointer (with an
unrolled loop!).

[srdjan, 2012-03-13 16:57:00]

https://chromiumcodereview.appspot.com/9693020/diff/2019/runtime/vm/code_gene...
File runtime/vm/code_generator_ia32.cc (right):

https://chromiumcodereview.appspot.com/9693020/diff/2019/runtime/vm/code_gene...
runtime/vm/code_generator_ia32.cc:574: const int base =
parsed_function_.first_local_index();
On 2012/03/13 12:31:08, kmillikin wrote:
> I think with your change to make local_count() include the number of copied
> parameters, you will want something like:
> 
> const int base = parsed_function_.first_local_index();
> const int count =
>   parsed_function_.local_count() - parsed_function_.copied_parameter_count();
> for (int index = 0; index < count; ++index) ...
> 
> Otherwise we're needlessly initializing above the stack pointer (with an
> unrolled loop!).

Excluding num_copied_parameters from stack_local_count.