On 2020-08-31 13:41, Corinna Vinschen wrote: > On Aug 31 13:24, Brian Inglis wrote: >> On 2020-08-31 12:45, Corinna Vinschen wrote: >>> On Aug 31 09:37, Brian Inglis wrote: >>>> On 2020-08-31 01:35, Corinna Vinschen wrote: >>>>> On Aug 30 14:39, Brian Inglis wrote: >>>>>> On 2020-08-30 07:00, Corinna Vinschen wrote: >>>>>>> On Aug 29 08:52, airplanemath via Cygwin wrote: >>>>>>>> I have two reports. A brief description of the system: >>>>>>>> $ uname -a | sed "s/${HOSTNAME}/\${HOSTNAME}/g" >>>>>>>> CYGWIN_NT-10.0 ${HOSTNAME} 3.1.7(0.340/5/3) 2020-08-22 17:48 x86_64 >>>>>>>> Cygwin >>>>>> ... >>>>>>>> $ cat test.c >>>>>>>> #include <math.h> >>>>>>>> #include <stdio.h> >>>>>>>> #include <stdlib.h> >>>>>>>> >>>>>>>> int main(int argc, char *argv[]) { >>>>>>>> long double a, b, c; >>>>>>>> char *num_end = NULL; >>>>>>>> a = b = c = 0.0L; >>>>>>>> if (argc != 2) { >>>>>>>> fprintf(stderr, "Usage: %s NUMBER\n", argv[0]); >>>>>>>> exit(1); >>>>>>>> } >>>>>>>> a = strtold(argv[1], &num_end); >>>>>>>> b = modfl(a, &c); >>>>>>>> printf("%Lf %Lf %Lf\n", a, b, c); >>>>>>>> return 0; >>>>>>>> } >>>>>>> >>>>>>> This is a bug in the assembler code taken from Mingw-w64. The bug has >>>>>>> been fixed upstream, so I just pulled in the upstream fixes. >>>>>> >>>>>> The 64 bit fix doesn't pop eax but *now* flags eax as clobbered, whereas >>>>>> the 32 >>>>>> bit fix both pops and *now* flags eax as clobbered, which it really >>>>>> doesn't need >>>>>> to do. Is this inconsistent treatment correct? >>>>> >>>>> You may be right that this is not necessary on i686, but it doesn't >>>>> hurt either and I'd like to stick to the upstream code if possible. >>>> >>>> The upstream patch changed only amd64/x86_64 code sequences for multiple >>>> modules >>>> including modfl, and left i386/x86 untouched for those modules. >> >> Just pointing out that they only modify their amd64/x86_64 code which doesn't >> push/pop rax/eax: > > Where are you looking at? As you could see from my output, I was > looking at the master branch of the upstream repo.
Sorry I didn't see your point there as I wasn't aware there were SF repos. > This lengthy discussion for a minor asm snippet doesn't make any sense. > If you think this is wrong, send patches to cygwin-patches and explain > where you got it from, preferrably as a git patch from the upstream > repo. Sorry for wasting your time. I was looking at the bug/patch content and didn't realize someone later added a bogus clobber on their x86 code path. -- Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada This email may be disturbing to some readers as it contains too much technical detail. Reader discretion is advised. [Data in IEC units and prefixes, physical quantities in SI.] -- Problem reports: https://cygwin.com/problems.html FAQ: https://cygwin.com/faq/ Documentation: https://cygwin.com/docs.html Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple