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Created on 2020-10-22 23:35 by lys.nikolaou, last changed 2022-04-11 14:59 by admin. This issue is now closed.
| Pull Requests | |||
|---|---|---|---|
| URL | Status | Linked | Edit |
| PR 22111 | merged | lys.nikolaou, 2020-10-22 23:37 | |
| PR 23011 | merged | lys.nikolaou, 2020-10-27 23:49 | |
| Messages (5) | |||
|---|---|---|---|
| msg379384 - (view) | Author: Lysandros Nikolaou (lys.nikolaou) *  |
Date: 2020-10-22 23:35 | |
We can avoid having to go through all the invalid rules (which might be a significant performance boost, since these may call expensive rules like primary or others), if we run the parser two times. On the first run, all the invalid rules are disabled and do not get expanded. If a parse failure occurs anywhere, then we run the parser a second time with all these rules enabled, in order to get the correct error message. Some benchmarking by Pablo show a ~4% speedup in the stdlib benchmark and a ~10% in the xxl benchmark. |
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| msg379508 - (view) | Author: Terry J. Reedy (terry.reedy) * |
Date: 2020-10-24 01:17 | |
Since I do a lot of interactive compiling, I appreciate faster feedback. How much will the slowdown be on errors? |
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| msg379697 - (view) | Author: Lysandros Nikolaou (lys.nikolaou) * |
Date: 2020-10-26 22:41 | |
We do not have a big corpus of SyntaxErrors to test against, but some manual testing of running a file with a SyntaxError after a long complex line 1000 times shows no slowdown. We keep the token stream for the second run, so we don't need to run the tokenizer all over again and the parsing is done much more quickly. |
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| msg379698 - (view) | Author: Lysandros Nikolaou (lys.nikolaou) * |
Date: 2020-10-26 22:42 | |
New changeset bca701403253379409dece03053dbd739c0bd059 by Lysandros Nikolaou in branch 'master': bpo-42123: Run the parser two times and only enable invalid rules on the second run (GH-22111) https://github.com/python/cpython/commit/bca701403253379409dece03053dbd739c0bd059 |
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| msg379811 - (view) | Author: Lysandros Nikolaou (lys.nikolaou) * |
Date: 2020-10-28 00:14 | |
New changeset 24a7c298d47658295673dc04d1b6d59f2b200a7c by Lysandros Nikolaou in branch '3.9': [3.9] bpo-42123: Run the parser two times and only enable invalid rules on the second run (GH-22111) (GH-23011) https://github.com/python/cpython/commit/24a7c298d47658295673dc04d1b6d59f2b200a7c |
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| History | |||
|---|---|---|---|
| Date | User | Action | Args |
| 2022-04-11 14:59:37 | admin | set | github: 86289 |
| 2020-10-28 00:14:18 | lys.nikolaou | set | messages: + msg379811 |
| 2020-10-27 23:49:54 | lys.nikolaou | set | pull_requests: + pull_request21927 |
| 2020-10-26 22:42:38 | lys.nikolaou | set | status: open -> closed resolution: fixed stage: patch review -> resolved |
| 2020-10-26 22:42:10 | lys.nikolaou | set | messages: + msg379698 |
| 2020-10-26 22:41:15 | lys.nikolaou | set | messages: + msg379697 |
| 2020-10-24 01:17:28 | terry.reedy | set | nosy:
+ terry.reedy messages: + msg379508 title: Run the two times, only enable invalid_* rules on the second run -> Run parser twice; enable invalid_* rules only on the second run |
| 2020-10-22 23:37:42 | lys.nikolaou | set | keywords:
+ patch stage: patch review pull_requests: + pull_request21835 |
| 2020-10-22 23:35:43 | lys.nikolaou | create | |