JRuby invokedynamic updates

[Charles Oliver Nutter]

On Wed, Aug 10, 2011 at 11:02 PM, Charles Oliver Nutter
<headius at headius.com> wrote:
> I've added bench/bench_fib_complex.rb. This runs the original fib
> along with three variations:
>
> * One that uses constants for the literals 1 and 2 in the code
> * One that dispatches to other Ruby methods for the <, -, and + calls
> * One that does both
>
> Performance is perhaps most easily explained by showing the numbers:

After talking with Christian I realized that the constant-based
versions were not getting fully bound with invokedynamic because they
have pre/post logic (specifically, they need to update some
thread-local frame state in JRuby). Ignore those results for the
moment.

There does still seem to be a problem with switchpoints though. I
stripped out all but the "additional calls" version and compared
switchpoint invalidation with normal.


headius at headius-desktop:~/projects/jruby$
JAVA_HOME=~/hsx-hotspot/build/linux/jdk-linux-i586/ bin/jruby --server
bench/bench_fib_complex.rb 5 35
fib with additional calls
9227465
  2.180000   0.000000   2.180000 (  2.070000)
fib with additional calls
9227465
  1.829000   0.000000   1.829000 (  1.829000)
fib with additional calls
9227465
  1.870000   0.000000   1.870000 (  1.870000)
fib with additional calls
9227465
  1.642000   0.000000   1.642000 (  1.642000)
fib with additional calls
9227465
  1.639000   0.000000   1.639000 (  1.639000)

headius at headius-desktop:~/projects/jruby$
JAVA_HOME=~/hsx-hotspot/build/linux/jdk-linux-i586/ bin/jruby --server
-Xinvokedynamic.invocation.switchpoint=true bench/bench_fib_complex.rb
5 35
fib with additional calls
9227465
  5.951000   0.000000   5.951000 (  5.841000)
fib with additional calls
9227465
  5.538000   0.000000   5.538000 (  5.538000)
fib with additional calls
9227465
  5.531000   0.000000   5.531000 (  5.531000)
fib with additional calls
9227465
  5.503000   0.000000   5.503000 (  5.503000)
fib with additional calls
9227465
  5.505000   0.000000   5.505000 (  5.505000)

My quick look through inlining shows that "plus", "minus", "lt" all
inline into fib_ruby3 ok, as do the binops they call. fib_ruby3
appears to recursively inline one level. I did not see any obvious
failures in inlining, but there's something not right here.

- Charlie