1/* 2 Copyright (c) 2015, Synopsys, Inc. All rights reserved. 3 4 Redistribution and use in source and binary forms, with or without 5 modification, are permitted provided that the following conditions are met: 6 7 1) Redistributions of source code must retain the above copyright notice, 8 this list of conditions and the following disclaimer. 9 10 2) Redistributions in binary form must reproduce the above copyright notice, 11 this list of conditions and the following disclaimer in the documentation 12 and/or other materials provided with the distribution. 13 14 3) Neither the name of the Synopsys, Inc., nor the names of its contributors 15 may be used to endorse or promote products derived from this software 16 without specific prior written permission. 17 18 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 19 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 22 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28 POSSIBILITY OF SUCH DAMAGE. 29*/ 30 31/* This implementation is optimized for performance. For code size a generic 32 implementation of this function from newlib/libc/string/strlen.c will be 33 used. */ 34#if !defined (__OPTIMIZE_SIZE__) && !defined (PREFER_SIZE_OVER_SPEED) 35 36#include "asm.h" 37 38#if (defined (__ARC600__) || !defined (__ARC_NORM__)) && !defined (__ARC601__) \ 39 && defined (__ARC_BARREL_SHIFTER__) 40/* This code is optimized for the ARC600 pipeline. */ 41 42ENTRY (strlen) 43 or r3,r0,7 44 ld r2,[r3,-7] 45 ld.a r6,[r3,-3] 46 mov r4,0x01010101 47 ; uses long immediate 48#ifdef __LITTLE_ENDIAN__ 49 asl_s r1,r0,3 50 btst_s r0,2 51 asl r7,r4,r1 52 ror r5,r4 53 sub r1,r2,r7 54 bic_l r1,r1,r2 55 mov.eq r7,r4 56 sub r12,r6,r7 57 bic r12,r12,r6 58 or.eq r12,r12,r1 59 and r12,r12,r5 60 brne r12,0,.Learly_end 61#else /* BIG ENDIAN */ 62 ror r5,r4 63 btst_s r0,2 64 mov_s r1,31 65 sub3 r7,r1,r0 66 sub r1,r2,r4 67 bic_l r1,r1,r2 68 bmsk r1,r1,r7 69 sub r12,r6,r4 70 bic r12,r12,r6 71 bmsk.ne r12,r12,r7 72 or.eq r12,r12,r1 73 and r12,r12,r5 74 brne r12,0,.Learly_end 75#endif /* ENDIAN */ 76 77.Loop: 78 ld_s r2,[r3,4] 79 ld.a r6,[r3,8] 80 ; stall for load result 81 sub r1,r2,r4 82 bic_s r1,r1,r2 83 sub r12,r6,r4 84 bic r12,r12,r6 85 or_s r12,r12,r1 86 and r12,r12,r5 87 breq_s r12,0,.Loop 88.Lend: 89 and.f r1,r1,r5 90 sub.ne r3,r3,4 91#ifdef __LITTLE_ENDIAN__ 92 mov.eq r1,r12 93 asr.f 0,r1,8 94 bmsk.f 0,r1,15 95 sub r0,r3,r0 96 add.cc r0,r0,1 97 jne.d [blink] 98 asl.f 0,r1,9 99 j_s.d [blink] 100 sbc r0,r0,-2 101#else /* BIG ENDIAN */ 102 mov.eq r2,r6 103 asl_s r2,r2,7 104 mov.eq r1,r12 105 bic_s r1,r1,r2 106 asr.f 0,r1,16 107 sub r0,r3,r0 108 add.pl r0,r0,1 109 jne.d [blink] 110 add.eq r0,r0,1 111 j_s.d [blink] 112 add.cc r0,r0,1 113#endif /* ENDIAN */ 114 115 .balign 4 116.Learly_end: 117 b.d .Lend 118 sub_s.ne r1,r1,r1 119ENDFUNC (strlen) 120#endif /* (__ARC600__ || !__ARC_NORM__) && !__ARC601__ && __ARC_BARREL_SHIFTER__ */ 121 122#endif /* !__OPTIMIZE_SIZE__ && !PREFER_SIZE_OVER_SPEED */ 123
