From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 27795 invoked by alias); 1 Mar 2013 17:36:34 -0000 Received: (qmail 26627 invoked by uid 22791); 1 Mar 2013 17:36:13 -0000 X-SWARE-Spam-Status: No, hits=-5.4 required=5.0 tests=AWL,BAYES_00,DKIM_SIGNED,DKIM_VALID,FREEMAIL_ENVFROM_END_DIGIT,FREEMAIL_FROM,KHOP_RCVD_TRUST,KHOP_THREADED,RCVD_IN_DNSWL_LOW,RCVD_IN_HOSTKARMA_YE X-Spam-Check-By: sourceware.org Received: from mail-pa0-f51.google.com (HELO mail-pa0-f51.google.com) (209.85.220.51) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 01 Mar 2013 17:36:02 +0000 Received: by mail-pa0-f51.google.com with SMTP id hz1so1939434pad.10 for ; Fri, 01 Mar 2013 09:36:00 -0800 (PST) X-Received: by 10.68.31.73 with SMTP id y9mr15830121pbh.102.1362159360920; Fri, 01 Mar 2013 09:36:00 -0800 (PST) Received: from fremont.twiddle.net (50-194-63-110-static.hfc.comcastbusiness.net. [50.194.63.110]) by mx.google.com with ESMTPS id kl4sm12679430pbc.31.2013.03.01.09.35.59 (version=TLSv1.2 cipher=RC4-SHA bits=128/128); Fri, 01 Mar 2013 09:36:00 -0800 (PST) From: Richard Henderson To: libc-ports@sourceware.org Cc: joseph@codesourcery.com Subject: [PATCH v2 14/14] arm: Add optimized add_n and sub_n Date: Fri, 01 Mar 2013 17:36:00 -0000 Message-Id: <1362159320-5934-15-git-send-email-rth@twiddle.net> In-Reply-To: <1362159320-5934-1-git-send-email-rth@twiddle.net> References: <1362159320-5934-1-git-send-email-rth@twiddle.net> X-IsSubscribed: yes Mailing-List: contact libc-ports-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: libc-ports-owner@sourceware.org X-SW-Source: 2013-03/txt/msg00006.txt.bz2 Written from scratch rather than copied from GMP, due to LGPL 2.1 vs GPL 3, but tested with the GMP testsuite. This is 250% faster than the generic code as measured on Cortex-A15, and the same speed as GMP on the same core, and probably everywhere. --- * sysdeps/arm/add_n.S: New file. * sysdeps/arm/sub_n.S: New file. --- ports/sysdeps/arm/add_n.S | 83 +++++++++++++++++++++++++++++++++++++++++++++++ ports/sysdeps/arm/sub_n.S | 2 ++ 2 files changed, 85 insertions(+) create mode 100644 ports/sysdeps/arm/add_n.S create mode 100644 ports/sysdeps/arm/sub_n.S diff --git a/ports/sysdeps/arm/add_n.S b/ports/sysdeps/arm/add_n.S new file mode 100644 index 0000000..af69733 --- /dev/null +++ b/ports/sysdeps/arm/add_n.S @@ -0,0 +1,83 @@ +/* Copyright (C) 2013 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, see + . */ + +#include + + .syntax unified + .text + +#ifdef USE_AS_SUB_N +# define INITC cmp r0, r0 +# define OPC sbcs +# define RETC sbc r0, r0, r0; neg r0, r0 +# define FUNC __mpn_sub_n +#else +# define INITC cmn r0, #0 +# define OPC adcs +# define RETC mov r0, #0; adc r0, r0, r0 +# define FUNC __mpn_add_n +#endif + +/* mp_limb_t mpn_add_n(res_ptr, src1_ptr, src2_ptr, size) */ + +ENTRY (FUNC) + push { r4, r5, r6, r7, r8, r10, lr } + cfi_adjust_cfa_offset (28) + cfi_rel_offset (r4, 0) + cfi_rel_offset (r5, 4) + cfi_rel_offset (r6, 8) + cfi_rel_offset (r7, 12) + cfi_rel_offset (r8, 16) + cfi_rel_offset (r10, 20) + cfi_rel_offset (lr, 24) + + INITC /* initialize carry flag */ + tst r3, #1 /* count & 1 == 1? */ + add lr, r1, r3, lsl #2 /* compute end src1 */ + beq 1f + + ldr r4, [r1], #4 /* do one to make count even */ + ldr r5, [r2], #4 + OPC r4, r4, r5 + teq r1, lr /* end of count? (preserve carry) */ + str r4, [r0], #4 + beq 9f +1: + tst r3, #2 /* count & 2 == 2? */ + beq 2f + ldm r1!, { r4, r5 } /* do two to make count 0 mod 4 */ + ldm r2!, { r6, r7 } + OPC r4, r4, r6 + OPC r5, r5, r7 + teq r1, lr /* end of count? */ + stm r0!, { r4, r5 } + beq 9f +2: + ldm r1!, { r3, r5, r7, r10 } /* do four each loop */ + ldm r2!, { r4, r6, r8, ip } + OPC r3, r3, r4 + OPC r5, r5, r6 + OPC r7, r7, r8 + OPC r10, r10, ip + teq r1, lr + stm r0!, { r3, r5, r7, r10 } + bne 2b + +9: + RETC /* copy carry out */ + pop { r4, r5, r6, r7, r8, r10, pc } +END (FUNC) diff --git a/ports/sysdeps/arm/sub_n.S b/ports/sysdeps/arm/sub_n.S new file mode 100644 index 0000000..8eafa41 --- /dev/null +++ b/ports/sysdeps/arm/sub_n.S @@ -0,0 +1,2 @@ +#define USE_AS_SUB_N +#include "add_n.S" -- 1.8.1.2