Description

brandtbucher

opened on Jun 23, 2023

Issue body actions

...as discussed in faster-cpython/ideas#568.

By adding a dedicated instruction for converting values to bool, we can easily specialize the conditions of all remaining branches in the bytecode while keeping the branches themselves as "dumb" and simple as possible.

This is one of the few remaining common cases where a little specilization will give us a lot of useful information (such as "this branch won't execute arbitrary code") for higher tiers of optimization. Plus, the most common specializations (such as for bool or None) will be effectively no-ops.

Linked PRs

• GH-106008: Make implicit boolean conversions explicit #106003
• GH-106008: Fix refleak when peepholing None comparisons #106367

Reacted by sunmy2019

Activity

1. brandtbucher

   added

   performancePerformance or resource usagePerformance or resource usage

   interpreter-core(Objects, Python, Grammar, and Parser dirs)(Objects, Python, Grammar, and Parser dirs)

   3.13only security fixesonly security fixes

   on Jun 23, 2023
2. brandtbucher

   self-assigned this

   on Jun 23, 2023
3. brandtbucher

   added a commit that references this issue on Jun 29, 2023

   GH-106008: Make implicit boolean conversions explicit (GH-106003)

   7b2d94d
4. brandtbucher

   closed this as completedon Jun 29, 2023
5. pablogsal commented on Jul 3, 2023

   

   pablogsal

   on Jul 3, 2023

   Member

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   @brandtbucher Apparently this PR introduced a refleak in test_grammar:

   Raised RLIMIT_NOFILE: 256 -> 1024
   0:00:00 load avg: 14.52 Run tests sequentially
   0:00:00 load avg: 14.52 [1/1] test_grammar
   beginning 9 repetitions
   123456789
   .........
   test_grammar leaked [2, 2, 2, 2] references, sum=8
   test_grammar leaked [2, 2, 2, 2] memory blocks, sum=8
   test_grammar failed (reference leak)
   
   == Tests result: FAILURE ==
   
   1 test failed:
       test_grammar
   
   Total duration: 349 ms
   Tests result: FAILURE
   

   The previous commit builds correctly:

   ❯ git checkout HEAD^
   Previous HEAD position was 7b2d94d8751 GH-106008: Make implicit boolean conversions explicit (GH-106003)
   HEAD is now at 6e9f83d9aee GH-106250: Support insts using one cache entry and no oparg (GH-106252)
   
   ❯ make -j -s
   ...
   
   ❯ ./python.exe -m test test_grammar -R :
   Raised RLIMIT_NOFILE: 256 -> 1024
   0:00:00 load avg: 11.57 Run tests sequentially
   0:00:00 load avg: 11.57 [1/1] test_grammar
   beginning 9 repetitions
   123456789
   .........
   
   == Tests result: SUCCESS ==
   
   1 test OK.
   
   Total duration: 342 ms
   Tests result: SUCCESS
   

   can you take a look?
6. brandtbucher commented on Jul 3, 2023

   

   brandtbucher

   on Jul 3, 2023

   MemberAuthor

   More actions

   Huh. Yeah, I'll take a look.
7. brandtbucher

   reopened this on Jul 3, 2023
8. brandtbucher commented on Jul 3, 2023

   

   brandtbucher

   on Jul 3, 2023

   MemberAuthor

   More actions

   Ah, I think I found it.
9. pablogsal

   added a commit that references this issue on Jul 4, 2023

   GH-106008: Fix refleak when peepholing `None` comparisons (#106367)

   e4ba71f
10. brandtbucher

    closed this as completedon Jul 5, 2023
11. carljm

    added a commit that references this issue on Jul 5, 2023

    Merge branch 'main' into modulelocals

    4c59e51

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