From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jes Sorensen Date: Thu, 12 Oct 2000 16:13:15 +0000 Subject: Re: [Linux-ia64] avoiding float underflow software assist Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org >>>>> "Pete" = Pete Wyckoff writes: Pete> jes@linuxcare.com said: >> We discussed this recently and David strongly opted for glibc >> setting s2/s3 the same way we set s0. I need to look closer at this >> in order to figure out how to deal with the get-then-set case but I >> think it's coming. Pete> There's this method of masking just the control bits of sf0 into Pete> sf* if you'd rather not provide direct library access to the Pete> fpsr. E.g., to set ftz in s0: Pete> asm volatile("fsetc.s0 0x7f, 0x01"); Pete> Or dup s0 into s2: Pete> asm volatile("fsetc.s2 0x7f, 0x00"); Pete> Not sure if/why intel gave us this instruction. Perhaps Pete> switching speed is important to some apps. Hmmm need to go read manuals when I get back from Atlanta. Thanks Jes