------- Comment #6 from pinskia at gmail dot com 2007-06-12 17:56 ------- Subject: Re: Unnecessary conversion from short to unsigend short breaks vectorization
On 12 Jun 2007 17:53:19 -0000, gangren at google dot com <[EMAIL PROTECTED]> wrote: > I'm aware of integral promotion. But not quite understand why we can optimize > (short)((int)short_var + (int)short_var) to (short)((unsigned short)short_var > + > (unsigned short)short_var), but not to (short)((short)short_var + > (short)short_var)? Is it because unsigned short has different overflow > handling? Yes, signed short has undefined overflow, while unsigned is defined as wrapping. --Pinski -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32309
