GH-135379: Specialize int operations for compact ints only #135668
+515
−283
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
…tion in case of overflow
|
Can you please add tests for the new synbol to optimizer_symbols.c? |
| return; | ||
| case JIT_SYM_KNOWN_VALUE_TAG: | ||
| if (!PyLong_CheckCompact(sym->value.value)) { | ||
| Py_CLEAR(sym->value.value); |
There was a problem hiding this comment.
I don't think you need to clear things here? It's automatically cleared on finalization of the whole optimizer I think.
There was a problem hiding this comment.
We need to do it here (we do the same in _Py_uop_sym_set_type) as we are changing the tag, so the finalization won't know there was an object there.
There was a problem hiding this comment.
AH ok that's very tricky! Good observation.
Fidget-Spinner
approved these changes
Jun 18, 2025
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This changes the way we handle ints during specialization.
Instead of handling all ints we only specialize for compact ints.
Since compact ints represent the large majority of ints we get a faster common path, at the cost of a few more de-optimizations.
Using compact ints only, and de-optimizing in the extremely rare no-memory case, we can simplify the performance critical paths for integer operations.
This is helpful for top-of-stack caching as the newer simpler instructions to not escape or need to handle errors, so avoids the need to spill to memory.
This also gives us the potential to use
BINARY_OP_EXTENDfor multi-digit ints in the future.