compiler_rt: fix __clzsi2_thumb1 (incorrect lookup table usage) #22367
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GalaxyShard
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A bit annoying that we apparently don't have test coverage of this. I'm half tempted to just delete this Thumb-1 specific code because, honestly, why? Anyway, this is effectively a revert of #22051. We should avoid the use of the |
I'm not entirely sure how to fix this without causing #22050 again, unless the generic implementation is used instead of the thumb1 implementation. Using the generic one might have a performance impact though. |
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alexrp
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Jan 1, 2025
GalaxyShard
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alexrp
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Originally the code loaded the (first 4 bytes of the) lookup table into r3 instead of the address of the lookup table, resulting in the memory address 02020100 (the lookup table bytes, in little endian) being dereferenced instead of the address of the lookup table.