From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21900 invoked by alias); 20 Jan 2006 16:00:32 -0000 Received: (qmail 21849 invoked by uid 22791); 20 Jan 2006 16:00:27 -0000 X-Spam-Check-By: sourceware.org Received: from sunsite.ms.mff.cuni.cz (HELO sunsite.mff.cuni.cz) (195.113.15.26) by sourceware.org (qpsmtpd/0.31) with ESMTP; Fri, 20 Jan 2006 16:00:17 +0000 Received: from sunsite.mff.cuni.cz (sunsite.mff.cuni.cz [127.0.0.1]) by sunsite.mff.cuni.cz (8.13.1/8.13.1) with ESMTP id k0KG0AGG024432; Fri, 20 Jan 2006 17:00:10 +0100 Received: (from jj@localhost) by sunsite.mff.cuni.cz (8.13.1/8.13.1/Submit) id k0KG06Bd024430; Fri, 20 Jan 2006 17:00:06 +0100 Date: Fri, 20 Jan 2006 16:00:00 -0000 From: Jakub Jelinek To: Ulrich Drepper , Roland McGrath , Steven Munroe Cc: Glibc hackers Subject: [PATCH] Use fsqrt and fsqrts unconditionally on ppc64 Message-ID: <20060120160006.GM4625@sunsite.mff.cuni.cz> Reply-To: Jakub Jelinek Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4.1i Mailing-List: contact libc-hacker-help@sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-hacker-owner@sourceware.org X-SW-Source: 2006-01/txt/msg00083.txt.bz2 Hi! Any reason why fsqrt{,s} use is conditional even in 64-bit glibc? sysdeps/powerpc/fpu/e_sqrt{,f}.c guards the insn use with: /* If the CPU is 64-bit we can use the optional FP instructions we. */ if ((GLRO (dl_hwcap) & PPC_FEATURE_64) != 0) and otherwise falls back to __slow_ieee754_sqrt{,f}. But in 64-bit code, I'd say we can always assume the CPU is 64-bit and PPC_FEATURE_64 is set and get rid of an unneeded runtime memory load, masking and more importantly quite large fallback routine. 2006-01-20 Jakub Jelinek * sysdeps/powerpc/powerpc64/fpu/e_sqrt.c: New file. * sysdeps/powerpc/powerpc64/fpu/e_sqrtf.c: New file. * sysdeps/powerpc/fpu/bits/mathinline.h (__CPU_HAS_FSQRT): Define. (__ieee754_sqrt, __ieee754_sqrtf): Use it. --- libc/sysdeps/powerpc/powerpc64/fpu/e_sqrt.c.jj 2006-01-20 16:36:49.000000000 +0100 +++ libc/sysdeps/powerpc/powerpc64/fpu/e_sqrt.c 2006-01-20 16:39:05.000000000 +0100 @@ -0,0 +1,29 @@ +/* Double-precision floating point square root. + Copyright (C) 1997, 2002, 2003, 2004, 2006 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include +#include + +double +__ieee754_sqrt (double x) +{ + double z; + __asm __volatile ("fsqrt %0,%1" : "=f" (z) : "f" (x)); + return z; +} --- libc/sysdeps/powerpc/powerpc64/fpu/e_sqrtf.c.jj 2006-01-20 16:36:52.000000000 +0100 +++ libc/sysdeps/powerpc/powerpc64/fpu/e_sqrtf.c 2006-01-20 16:37:55.000000000 +0100 @@ -0,0 +1,29 @@ +/* Single-precision floating point square root. + Copyright (C) 1997, 2003, 2004, 2006 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include +#include + +float +__ieee754_sqrtf (float x) +{ + double z; + __asm ("fsqrts %0,%1" : "=f" (z) : "f" (x)); + return z; +} --- libc/sysdeps/powerpc/fpu/bits/mathinline.h.jj 2004-10-01 12:05:04.000000000 +0200 +++ libc/sysdeps/powerpc/fpu/bits/mathinline.h 2006-01-20 16:45:16.000000000 +0100 @@ -1,5 +1,5 @@ /* Inline math functions for powerpc. - Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2004 + Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2004, 2006 Free Software Foundation, Inc. This file is part of the GNU C Library. @@ -123,12 +123,18 @@ __NTH (fdimf (float __x, float __y)) #endif /* !__NO_MATH_INLINES && __OPTIMIZE__ */ /* This code is used internally in the GNU libc. */ -# ifdef __LIBC_INTERNAL_MATH_INLINES +#ifdef __LIBC_INTERNAL_MATH_INLINES #include #include #include +# if __WORDSIZE == 64 +# define __CPU_HAS_FSQRT 1 +# else +# define __CPU_HAS_FSQRT ((GLRO(dl_hwcap) & PPC_FEATURE_64) != 0) +# endif + extern double __slow_ieee754_sqrt (double); __MATH_INLINE double __NTH (__ieee754_sqrt (double __x)) @@ -136,7 +142,7 @@ __NTH (__ieee754_sqrt (double __x)) double __z; /* If the CPU is 64-bit we can use the optional FP instructions we. */ - if ((GLRO(dl_hwcap) & PPC_FEATURE_64) != 0) + if (__CPU_HAS_FSQRT) { /* Volatile is required to prevent the compiler from moving the fsqrt instruction above the branch. */ @@ -158,7 +164,7 @@ __NTH (__ieee754_sqrtf (float __x)) float __z; /* If the CPU is 64-bit we can use the optional FP instructions we. */ - if ((GLRO(dl_hwcap) & PPC_FEATURE_64) != 0) + if (__CPU_HAS_FSQRT) { /* Volatile is required to prevent the compiler from moving the fsqrts instruction above the branch. */ @@ -172,5 +178,5 @@ __NTH (__ieee754_sqrtf (float __x)) return __z; } -# endif /* __LIBC_INTERNAL_MATH_INLINES */ +#endif /* __LIBC_INTERNAL_MATH_INLINES */ #endif /* __GNUC__ && !_SOFT_FLOAT */ Jakub