add SLJIT_REV16PACK and SLJIT_REV32PACK #206
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Including implementations without emulation for ARM, MIPS and LoongArch. Allow 16/32bit bswap in a packed integer, so it could provide faster results by doing 2 or 4 operations at once. While at it add an instruction to ARM 32bit to make things slightly more efficient and do some refactoring on related test cases.
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Is there a use case for this? When I was thinking about this before, I decided not to do it until the support needed for something. For example, the normal rev is needed for big-endian WebAssembly support, since WebAssembly must use little endian memory accesses. |
no, was more interested on feedback on the design and code, as well as the potential performance improvements if bulk bswaps were needed as well as if it was worth doing it here or going all the way to vector instructions (most likely the later which seems to be well supported at least in s390x). |
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Might become useful when byte swapping in bulk and therefore as it is meant to be performance sensitive, not Including (at least for now) emulation.
Not particularly fond of he name, but at least keeps the bit width of the instruction away from the bit width of the register size, even if a mouthful as
SLJIT_REV16PACK32