[avr-libc-dev] Looking to contribute

2016-12-08 Thread Andrew Louis
Hello all, My name is Andrew Louis. I am a student pursuing an MS in computer science at the University of Illinois at Urbana-Champaign. For some time now, I have been looking to get involved in a free software project. I began looking through the "Contributors Wanted" listings on savannah and

Re: [avr-libc-dev] [untested PATCH] Save 11 instructions in vfprintf_flt.o

2016-12-08 Thread George Spelvin
>> + * Unlike "if (src & smask) dst |= dmask", which is also two instructions > This is confusing because the BST + BLD code below is not a replacement > for what the C code is indicating. For example the C code never clears > the bit as opposed to BLD. >> + * and two cycles, this overwrites the

Re: [avr-libc-dev] [untested PATCH] Save 11 instructions in vfprintf_flt.o

2016-12-08 Thread Georg-Johann Lay
George Spelvin schrieb: As part of poking around vfprintf.c, I came across this low-hanging fruit. I'm waiting to test all of my printf changes together, but I thought I'd throw it out for comment early. I presume this sort of thing is okay? Basically, by reversing the sense of the FL_FLTUPP f

Re: [avr-libc-dev] Interested in 64-bit printf support?

2016-12-08 Thread George Spelvin
> The reworked version comes up with 110 bytes (still asserting MUL). Nicely done. > perf-metering with avrtest reveals a run time from ~3100 up to < 4800 > ticks; high as expected. While mine is 3161 cycles worst case (64 ones), or 4045 if !MUL. So yours is actually not too unreasonable *if*

Re: [avr-libc-dev] I just noticed OPTIMIZE_SPEED

2016-12-08 Thread Georg-Johann Lay
On 06.12.2016 23:59, Joerg Wunsch wrote: As George Spelvin wrote: Perhaps the two different reduction-mod-5 schemes should depend on OPTIMIZE_SPEED? Doesn't really matter much. Since the library is pre-compiled, you cannot map it to the user's -Ox compiler option anyway. As Johann already e

Re: [avr-libc-dev] Interested in 64-bit printf support?

2016-12-08 Thread Georg-Johann Lay
On 08.12.2016 00:34, George Spelvin wrote: Georg-Johann Lay wrote: The algo is rather slow because it always iterates over all digits, i.e. it won't run faster for small numbers. Have fun! Code size is ~140 bytes. Well, it's bigger (140 > 124), slower, and doesn't handle sizes *other* than