From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeffrey A Law To: Stan Cox Cc: egcs@cygnus.com Subject: Re: x86 alignment stuff Date: Sun, 22 Feb 1998 18:48:00 -0000 Message-id: <6298.888202223@hurl.cygnus.com> References: X-SW-Source: 1998-02/msg01039.html In message < nrra4vp32s.fsf_-_@rtl.cygnus.com >you write: > >Does anybody know why we don't items in the static store on the > >x86? Seems to me we can align stuff in the static store via > >DATA_ALIGNMENT and friends without breaking ABI compatability. > > The x86 ABI alignment is: char (1), short (2), int/long/enum (4), > *type (4), float (4), double (4), long double (4). > double and long double are of course the interesting ones. Those specify minimum alignments. What I'm looking for is any reason why we could not provide more alignment for some items in the static store. Seems to me like we could provide 8 byte alignment for doubles, long doubles and arrays which have doubles or long doubles as elements. For at least the Fortran folks this would get most of their data aligned on a suitable boundary to improve performance. Note that we'd also want to look into aligning doubles and long doubles in the constant pool! Anyone want a nice little project to improve x86 performance? :-) jeff