Review Request: Zero speedup

[Gary Benson]

Hi all,

Zero's normal and native method entries both call
methodOopDesc::result_type when a method returns without an exception.
I didn't realise, but this parses the method's signature, so is pretty
slow.  This webrev makes Zero figure out result types in a similar way
to the x86 and sparc C++ interpreter implementations.

  http://cr.openjdk.java.net/~gbenson/zero-speedup-01/

Some quick and dirty SPECjvm98 numbers (not produced in compliance
with the SPECjvm98 run rules and therefore not comparable with
SPECjvm98 metrics):

                   Old       New  Speedup
  compress      151.38    136.34     9.9%
  jess           38.81     28.64    26.2%
  db             73.22     59.11    19.3%
  javac          43.10     34.84    19.2%
  mpegaudio     108.47    100.61     7.2%
  mtrt           38.66     29.30    24.2%
  jack           27.68     22.40    19.1%

I don't have a bug id for this.

Cheers,
Gary

-- 
http://gbenson.net/