Remove duplicated code

[jahirfiquitiva]

Description

I was checking at the source code of the buffer.js file, and noticed that certain parts of the code could be simplified.

Basically, you were checking for some lowercase expected text and then doing "something". If the text was not lowercase, you would make it lowercase and then do the exact same check and the exact same "something".

So, I thought, why not ensuring the text is already lowercase and then do the checks only once?

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• documentation is changed or added
• commit message follows commit guidelines

Notes

Unfortunately I didn't read or noticed the Pull Request contribution guidelines before creating it, so I hope there's no issue into getting the changes merged (if they deserve to be merged).

Thanks a ton

[ChALkeR]

That function was written that way because of performance considerations.
See e.g. #12361 which touched that code. That was fairly long ago, though.

How does this change affect buffers benchmarks? See the doc on how to run those.

[refack]

Hello @jahirfiquitiva and thank you for the contribution!

I've gone ahead and started an automated benchmark compare job, I'm interested to see what it comes up with...

Good luck 🤞

[jahirfiquitiva]

@ChALkeR thanks for the info, I also thought there might be a reason why it was left that way, but I didn't know about the benchmarks.

@refack thank you so much! I was trying to run one by one but your solution is much better.

Excited to know those results 🙂

[refack]

Seems like that duplicate code still has a performance benefit.

Summary of only significant results.

	confidence	improvement	(*)	(**)	(***)
buffers/buffer-write-string.js n=10000000 len=10 args='' encoding='UCS-2'	***	8.85 %	±2.35%	±3.15%	±4.12%
buffers/buffer-write-string.js n=10000000 len=10 args='offset' encoding='UCS-2'	***	6.87 %	±3.67%	±4.94%	±6.55%
buffers/buffer-write-string.js n=10000000 len=10 args='offset+length' encoding='UCS-2'	***	6.69 %	±2.23%	±3.00%	±3.97%
buffers/buffer-write-string.js n=10000000 len=2048 args='' encoding='UCS-2'	***	5.01 %	±1.73%	±2.31%	±3.01%
buffers/buffer-write-string.js n=10000000 len=2048 args='offset' encoding='UCS-2'	***	4.29 %	±2.23%	±2.98%	±3.89%
buffers/buffer-write-string.js n=10000000 len=2048 args='offset+length' encoding='UCS-2'	***	4.20 %	±0.91%	±1.22%	±1.58%
buffers/buffer-write-string.js n=10000000 len=2048 args='offset' encoding='latin1'	***	-9.91 %	±2.37%	±3.16%	±4.14%
buffers/buffer-write-string.js n=10000000 len=2048 args='offset+length' encoding='latin1'	***	-9.80 %	±3.37%	±4.52%	±5.95%
buffers/buffer-write-string.js n=10000000 len=10 args='offset' encoding='binary'	***	-9.63 %	±2.36%	±3.14%	±4.09%
buffers/buffer-write-string.js n=10000000 len=2048 args='' encoding='latin1'	***	-9.39 %	±3.17%	±4.22%	±5.51%
buffers/buffer-write-string.js n=10000000 len=10 args='offset+length' encoding='latin1'	***	-9.30 %	±1.69%	±2.27%	±3.01%
buffers/buffer-write-string.js n=10000000 len=2048 args='offset+length' encoding='binary'	***	-9.26 %	±2.78%	±3.72%	±4.87%
buffers/buffer-write-string.js n=10000000 len=10 args='offset' encoding='latin1'	***	-9.12 %	±0.96%	±1.28%	±1.66%
buffers/buffer-write-string.js n=10000000 len=2048 args='offset' encoding='binary'	***	-9.10 %	±2.45%	±3.26%	±4.24%
buffers/buffer-write-string.js n=10000000 len=10 args='' encoding='ascii'	***	-9.03 %	±1.64%	±2.20%	±2.90%
buffers/buffer-write-string.js n=10000000 len=2048 args='offset+length' encoding='ascii'	***	-8.92 %	±3.29%	±4.41%	±5.79%
buffers/buffer-write-string.js n=10000000 len=10 args='offset+length' encoding='ascii'	***	-8.83 %	±2.19%	±2.92%	±3.81%
buffers/buffer-write-string.js n=10000000 len=2048 args='offset' encoding='ascii'	***	-8.82 %	±2.49%	±3.34%	±4.41%
buffers/buffer-write-string.js n=10000000 len=10 args='offset+length' encoding='binary'	***	-8.55 %	±2.23%	±2.97%	±3.87%
buffers/buffer-write-string.js n=10000000 len=10 args='' encoding='binary'	***	-8.53 %	±2.65%	±3.57%	±4.71%
buffers/buffer-write-string.js n=10000000 len=10 args='' encoding='utf8'	***	-8.08 %	±1.93%	±2.57%	±3.35%
buffers/buffer-write-string.js n=10000000 len=10 args='offset+length' encoding='utf8'	***	-6.90 %	±1.30%	±1.73%	±2.26%
buffers/buffer-write-string.js n=10000000 len=2048 args='' encoding='ascii'	***	-6.88 %	±3.23%	±4.30%	±5.60%
buffers/buffer-write-string.js n=10000000 len=10 args='offset' encoding='utf8'	***	-6.73 %	±2.08%	±2.77%	±3.60%
buffers/buffer-write-string.js n=10000000 len=10 args='' encoding='hex'	***	-6.33 %	±3.43%	±4.57%	±5.94%
buffers/buffer-write-string.js n=10000000 len=2048 args='' encoding='binary'	***	-5.83 %	±2.19%	±2.94%	±3.87%
buffers/buffer-write-string.js n=10000000 len=10 args='offset+length' encoding='hex'	***	-5.21 %	±2.32%	±3.09%	±4.02%
buffers/buffer-write-string.js n=10000000 len=10 args='offset' encoding='hex'	***	-4.39 %	±0.82%	±1.09%	±1.42%
buffers/buffer-write-string.js n=10000000 len=2048 args='offset+length' encoding='utf16le'	***	-4.36 %	±1.96%	±2.62%	±3.41%
buffers/buffer-write-string.js n=10000000 len=2048 args='' encoding='utf8'	***	-3.71 %	±1.98%	±2.64%	±3.46%
buffers/buffer-write-string.js n=10000000 len=2048 args='offset' encoding='utf8'	***	-2.52 %	±1.13%	±1.51%	±1.96%
buffers/buffer-write-string.js n=10000000 len=10 args='' encoding='latin1'	***	-10.90 %	±2.05%	±2.74%	±3.58%
buffers/buffer-write-string.js n=10000000 len=10 args='offset' encoding='ascii'	***	-10.84 %	±3.32%	±4.43%	±5.78%
buffers/buffer-write-string.js n=10000000 len=10 args='offset+length' encoding='utf16le'	***	-10.70 %	±3.01%	±4.00%	±5.21%
buffers/buffer-write-string.js n=10000000 len=10 args='' encoding='utf16le'	***	-10.47 %	±1.88%	±2.53%	±3.35%
buffers/buffer-write-string.js n=10000000 len=10 args='offset' encoding='utf16le'	***	-10.27 %	±2.12%	±2.84%	±3.71%
buffers/buffer-write-string.js n=10000000 len=2048 args='offset+length' encoding='utf8'	***	-1.61 %	±0.80%	±1.06%	±1.38%
buffers/buffer-write-string.js n=10000000 len=2048 args='offset' encoding='utf16le'	**	-2.68 %	±1.68%	±2.23%	±2.91%
buffers/buffer-write-string.js n=10000000 len=2048 args='offset' encoding='hex'	**	-0.98 %	±0.65%	±0.88%	±1.15%
buffers/buffer-write.js n=1000000 type='UInt16BE' buffer='fast'	*	-6.52 %	±4.95%	±6.62%	±8.67%
buffers/buffer-write.js n=1000000 type='UInt32BE' buffer='slow'	*	-6.30 %	±5.91%	±7.90%	±10.35%
buffers/buffer-write.js n=1000000 type='Int16LE' buffer='fast'	*	-5.20 %	±4.11%	±5.49%	±7.18%
buffers/buffer-write-string.js n=10000000 len=2048 args='' encoding='utf16le'	*	-2.84 %	±2.76%	±3.69%	±4.85%

All results FTR - https://gist.github.com/refack/abe23c6941cf9599f46146296e331cf0

[jahirfiquitiva]

Interesting ... Thanks for sharing @refack

[ChALkeR]

Yes, this seems to noticeably slow down small buffer writes with all specified encodings, except for UCS-2, and to improve the speed for UCS-2 writes somehow. Probably because it's the only one that was not normalized to ucs2 in tests.

[jahirfiquitiva]

Understood... I'll let you take the final decision 🙂

[Trott]

Hi, @jahirfiquitiva! Thanks again for the pull request. I'm going to close this one out, but I hope this doesn't discourage you from improving the code base in other ways!