RFR: 8299061: Using lambda to optimize GraphKit::compute_stack_effects() [v2]

[Tobias Hartmann]

On Tue, 20 Dec 2022 19:55:31 GMT, Xin Liu <xliu at openjdk.org> wrote:

>> Some bytecodes donot need rsize in GraphKit::compute_stack_effects(). 
>> This change defines rsize as a lambda and avoid computation if it's not in use. 
>> 
>> We utilize CTW($openjdk/test/hotspot/jtreg/testlibrary/ctw/dist) to test this patch.
>> We compile 2 builtin modules: java.base and jdk.compiler(javac).
>> 
>> 
>> JAVA_OPTIONS="-XX:+CITime -XX:-TieredCompilation" ./ctw.sh modules:java.base
>> JAVA_OPTIONS="-XX:+CITime -XX:-TieredCompilation" ./ctw.sh modules:jdk.compiler
>> 
>> For jdk.compiler module, the average compilation speed increases from 13236 bytes/s to 13303 bytes/s, or +0.51%.
>> For java.base module, the average compilation speed is almost same(+0.3%)
>> 
>> 
>> | java.base                 | before    | after     | diff  |
>> |---------------------------|-----------|-----------|-------|
>> | C2 Compile Time(s)        | 341.218   | 339.75    |       |
>> | Parse Time(s)             | 125.403   | 125.034   |       |
>> | ratio of parse            | 36.75%    | 36.80%    |       |
>> | throughput(bytes/s)       | 11841.628* | 11876.831 | 0.30% |
>> | Average compilation speed | 11779     | 11816     | 0.31% |
>> | Total compiled methods    | 58148     | 58158     |       |
>> |                           |           |           |       |
>> 
>> 
>> | jdk.compiler              | before    | after     |       |
>> |---------------------------|-----------|-----------|-------|
>> | C2 Compile Time(s)        | 66.486    | 66.087    |       |
>> | Parse Time(s)             | 21.877    | 21.731    |       |
>> | ratio of parse            | 32.90%    | 32.88%    |       |
>> | throughput(bytes/s)       | 14342.883 | 14436.494 | 0.65% |
>> | Average compilation speed | 13236     | 13303     | 0.51% |
>> | Total compiled methods    | 13734     | 13730     |       |
>> |                           |           |           |       |
>> 
>> 
>> *Throughtput is reported from Tier4 row. It's very close to 'Average compilation speed' but not exactly same. eg. here is from java.base module.
>> 
>> 
>> before:
>>   Tier4 {speed: 11841.628 bytes/s; standard: 339.754 s, 4014210 bytes, 58115 methods; osr:  0.345 s, 13109 bytes, 33 methods; nmethods_size: 52147560 bytes; nmethods_code_size: 32146360 bytes}
>> after:
>>   Tier4 {speed: 11876.831 bytes/s; standard: 338.350 s, 4009949 bytes, 58126 methods; osr:  0.368 s, 12951 bytes, 32 methods; nmethods_size: 52122744 bytes; nmethods_code_size: 32124952 bytes}
>
> Xin Liu has updated the pull request incrementally with one additional commit since the last revision:
> 
>   further simplify the lambda based on the feedbacks of reviewers.

Looks good to me too.

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Marked as reviewed by thartmann (Reviewer).

PR: https://git.openjdk.org/jdk/pull/11737