Towards support full range of small ints in bytecode #311
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WIP, for early review of approach. Do not merge.
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Superseded by #312. |
tannewt
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Oct 14, 2017
* atmel-samd: Add support for internal filesystems. This allows us to re-enable `os`. `random` is also enabled because it solely depends on `os`. Fixes micropython#266. Its also a pre-requisite for micropython#260. * atmel-samd: Update SAMD51 linker script comments and MICROPY_MAX_STACK_USAGE enabling.
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So, one issue we have is:
Encoding of int's apparently should be consistent with encoding of uint's. Then this patch tries to support encoding arbitrary uint's (and regardless of its bitsize). Let me know if you like and I clean it up (tests pass with it).
Then beyond uint's, varlen encoding for ints has its peculiarities. Note that I don't think that static biasing like you emit_write_byte_code_byte_int() with num += 0x800000 helps here. It turns "short" 0 in a big long value for example (I guess that's why you didn't make it varlen encoded, just static 3-byte). Obvious way to overcome that is to use "sign + magnitude" encoding (like floats), but that requires extra magic to handle MIN_INT, so I'd hope that some smart sign management allow to store two's complement still...