Message 348751 - Python tracker

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Author	methane
Recipients	christian.heimes, ezio.melotti, methane, miss-islington, mpaolini, ncoghlan, pablogsal, rhettinger, serhiy.storchaka, steve.dower
Date	2019-07-30.15:35:10
SpamBayes Score	-1.0
Marked as misclassified	Yes
Message-id	<1564500910.67.0.973515623864.issue37587@roundup.psfhosted.org>
In-reply-to

Content
Since scope of "c" is very wide, and there is even `&c` in the scope, compiler stores the `c` to stack every time on: c = PyUnicode_READ(kind, buf, next); That is the bottleneck. `if (strict && ...)` is not the bottleneck. My patch used a new variable with tight scope so compiler can bypass store it to the stack.

Since scope of "c" is very wide, and there is even `&c` in the scope, compiler stores the `c` to stack every time on:

  c = PyUnicode_READ(kind, buf, next);

That is the bottleneck.  `if (strict && ...)` is not the bottleneck.

My patch used a new variable with tight scope so compiler can bypass store it to the stack.

History
Date	User	Action	Args
2019-07-30 15:35:10	methane	set	recipients: + methane, rhettinger, ncoghlan, christian.heimes, ezio.melotti, serhiy.storchaka, steve.dower, mpaolini, pablogsal, miss-islington
2019-07-30 15:35:10	methane	set	messageid: <1564500910.67.0.973515623864.issue37587@roundup.psfhosted.org>
2019-07-30 15:35:10	methane	link	issue37587 messages
2019-07-30 15:35:10	methane	create