Has --dump-debug-dir behaviour changed in JDK9?

[Marcus Lagergren]

You are awesome, Chris!

/M

> On 10 Jun 2015, at 19:31, Chris Newland <cnewland at chrisnewland.com> wrote:
> 
> Thank you Sundar, that explains it perfectly.
> 
> JITWatch visualises JavaScript/bytecode/asm correctly with -ot=false on
> JDK9. I'll now try and make it work with optimistic typing enabled.
> 
> Cheers,
> 
> Chris
> @chriswhocodes
> 
> On Wed, June 10, 2015 05:22, A. Sundararajan wrote:
>> Hi,
>> 
>> 
>> Filed a bug to track for future reference:
>> https://bugs.openjdk.java.net/browse/JDK-8087102
>> 
>> 
>> Actually, this is not a bug. Two things:
>> 
>> 
>> 1) --compile-only / -co option is no longer mandatory to use
>> --debug-dump-dir option/
>> 2) optimistic types is off by default in jdk8u and it is on by default
>> with jdk9.
>> 
>> With optimistic types, code generation is lazier & optimistic -- code is
>> generated/re-generated as you run the code. With jdk9, you can either
>> 
>> 1) Turn off optimistic types with jdk9 (using -ot=false option) and dump
>> similar code as in jdk8u 2) or run the code (i.e., remove -co /
>> --compile-only option) and get
>> all generated (and regenerated) code dumped.
>> 
>> PS. I've resolved the bug as "not an issue".
>> 
>> 
>> Hope this explains,
>> -Sundar
>> 
>> 
>> On Wednesday 10 June 2015 02:55 AM, Chris Newland wrote:
>> 
>>> Hi,
>>> 
>>> 
>>> Has Nashorn's behaviour for dumping bytecode changed in JDK9?
>>> 
>>> 
>>> Given this JavaScript:
>>> https://gist.github.com/chriswhocodes/bfe139592adb846967d8
>>> 
>>> 
>>> Executed using
>>> $JAVA_HOME/bin/jjs -co --dump-debug-dir=. run.js
>>> 
>>> 
>>> Under 8u60b18 the bytecode is produced as expected:
>>> 
>>> 
>>> https://gist.github.com/chriswhocodes/e3a85c3613b084e45356
>>> 
>>> 
>>> This visualises correctly in JITWatch[1] and the bytecode maps back to
>>> the source as expected.
>>> 
>>> But under 9b67 only a small amount of bytecode is output that doesn't
>>> represent the source program:
>>> 
>>> https://gist.github.com/chriswhocodes/c6c6e33e7994c98d4975
>>> 
>>> 
>>> The correct program output is produced under both executions so I don't
>>> think the difference is down to dead code elimination.
>>> 
>>> Possible regression?
>>> 
>>> 
>>> Thanks,
>>> 
>>> 
>>> Chris
>>> @chriswhocodes
>>> 
>>> 
>>> [1] https://github.com/AdoptOpenJDK/jitwatch
>>> 
>>> 
>>> 
>> 
>> 
> 
>