py/emitinlinethumb: Shrink condition code lookups.#18997
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agatti wants to merge 1 commit intomicropython:masterfrom
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py/emitinlinethumb: Shrink condition code lookups.#18997agatti wants to merge 1 commit intomicropython:masterfrom
agatti wants to merge 1 commit intomicropython:masterfrom
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This commit optimises the lookup of opcodes' condition codes, in order to take up less code than before. The original data was held in a table containing the condition code value (an incrementing 0-based integer) and the two condition ASCII characters. Given that the condition code value also matches the entry's index in the table, that can be safely omitted. This saves 52 bytes when compiled for Thumb. Signed-off-by: Alessandro Gatti <a.gatti@frob.it>
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Code size report: |
Codecov Report✅ All modified and coverable lines are covered by tests. Additional details and impacted files@@ Coverage Diff @@
## master #18997 +/- ##
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Coverage 98.46% 98.46%
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Files 176 176
Lines 22784 22784
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Hits 22435 22435
Misses 349 349 ☔ View full report in Codecov by Sentry. 🚀 New features to boost your workflow:
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Summary
This PR optimises the lookup of opcodes' condition codes, in order to take up less code than before.
The original data was held in a table containing the condition code value (an incrementing 0-based integer) and the two condition ASCII characters. Given that the condition code value also matches the entry's index in the table, that can be safely omitted.
This saves 52 bytes when compiled for Thumb for QEMU.
Testing
The inline assembler test suite was run successfully on
QEMU/MPS2_AN385. Octoprobe run 423 is queued to test the behaviour on real hardware, mostly to see how the expanded test behaves on a low memory board (ADAFRUIT_ITSYBITSY_M0_EXPRESS).Generative AI
I did not use generative AI tools when creating this PR.