From: ardi <ardillasdelmonte@gmail.com>
To: musl@lists.openwall.com
Subject: [musl] Do you recommend using fmt_fp() and
Date: Thu, 18 Aug 2022 17:51:26 +0200 [thread overview]
Message-ID: <CA+fZqCXm-nAzf+j88EqTx_G6jCR-VMN5TyDmgvL-o9yNW+6BUw@mail.gmail.com> (raw)
Hi,
I'm looking for a small and robust dtoa-like implementation for quad
floats (IEEE binary128). The need is because I'm using John Hauser's
SoftFloat for IEEE binary128 computing, but I have no easy means for
converting such floats from/to strings (I can use the host
printf/strtold for 80bit extended long doubles, but I'm missing some
significant digits by doing that, and besides, if I ever build in a
host that considers long doubles as regular doubles, I'd lose even
more digits).
I've been considering gdtoa for some days, taking into account its
pros and cons, but I don't like its code size, its dependency on the
FPU flavour behaviour, and that it requires mutexes if it's used in
parallel.
So, I was looking at how musl does this. It appears to be in the
fmt_fp() function in vfprintf.c and in floatscan.c
It looks like I can modify these functions and force them to use the
binary128 type as provided by SoftFloat, instead of using long double.
But it can require quite a bit of surgery, so, before I get my hands
busy in it, I have to ask the question: Would you use this
implementation for my needs if you were me?
Did you adapt fmt_fp() and floatscan from older code? Was that code
ready for 128bit floats?
Or maybe you can recommend another dtoa-like code for 128bit floats?
Thanks a lot,
César
next reply other threads:[~2022-08-18 15:51 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-08-18 15:51 ardi [this message]
2022-08-19 3:19 ` Rich Felker
2022-08-23 17:00 ` ardi
2022-08-23 17:30 ` Rich Felker
2022-08-30 10:17 ` ardi
2022-08-30 12:26 ` Rich Felker
2022-09-04 19:52 ` ardi
2022-09-04 21:59 ` Rich Felker
2022-09-05 8:49 ` ardi
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