Author: Aart J.C. Bik
Date: 16:00:37 04/06/05
Go up one level in this thread
On March 28, 2005 at 08:16:33, Gerd Isenberg wrote: >There is one (minor) problem in the code above, using _mm_cmpeq_epi32(f,f) with >not initialized, but same arguments as -1 setter forcing pcmpeqd xmmi,xmmi, >where the initial value of xmmi don't cares. The debug version fires a runtime >exception, but the release version was a few cycles faster, using not >initialized xmm-register variables. Unfortunately there is no -1 setter like >_mm_setzero_si128() for zero - at least i don't find one. > >Cheers, >Gerd Hi Gerd, Indeed, only a “0”-setter is supported, not a “-1”-setter. In a future release of the Intel compiler, we plan to optimize the instructions used to implement intrinsics like _mm_set1_epi32(c) for various values of the constant, so that the user does not have to worry about what sequence is best for a given platform. Your posting has given me a good reason to expedite this process! Thanks. Aart Bik http://www.aartbik.com/
This page took 0 seconds to execute
Last modified: Thu, 15 Apr 21 08:11:13 -0700
Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.