[lwip-devel] SMEMCPY()

[Leon Woestenberg]

Hello,

I'm going to review the last one-and-a-half years of code submits, so
expect more noise here.

Over the last few years all 4 and 6 bytes copies seem to have moved to
the SMEMCPY macro, which is memcpy() by default.

SMEMCPY() is not documented well. I think it is intended for small
copies. Let's say small is <64 bytes.

My GCC does not inline memcpy() using -O2 for a 6 byte MAC address.

    5d66:       4658            mov     r0, fp
    5d68:       4651            mov     r1, sl
    5d6a:       2206            movs    r2, #6
    5d6c:       f018 fe5a       bl      1ea24 <memcpy>

Should be implement a byte-copy macro for SMEMCPY() in opt.h, instead
of calling memcpy()?

Who did performance measurements on this, before converting our code over?

Regards,
-- 
Leon