| /* Optimized strcpy for Xtensa. |
| Copyright (C) 2001, 2007 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., 51 Franklin Street - Fifth Floor, |
| Boston, MA 02110-1301, USA. */ |
| |
| #include "../../sysdeps/linux/xtensa/sysdep.h" |
| #include <bits/xtensa-config.h> |
| |
| #ifdef __XTENSA_EB__ |
| #define MASK0 0xff000000 |
| #define MASK1 0x00ff0000 |
| #define MASK2 0x0000ff00 |
| #define MASK3 0x000000ff |
| #else |
| #define MASK0 0x000000ff |
| #define MASK1 0x0000ff00 |
| #define MASK2 0x00ff0000 |
| #define MASK3 0xff000000 |
| #endif |
| |
| /* Do not use .literal_position in the ENTRY macro. */ |
| #undef LITERAL_POSITION |
| #define LITERAL_POSITION |
| |
| .text |
| .align 4 |
| .literal_position |
| __strncpy_aux: |
| |
| .Lsrc1mod2: /* src address is odd */ |
| l8ui a8, a3, 0 /* get byte 0 */ |
| addi a3, a3, 1 /* advance src pointer */ |
| s8i a8, a10, 0 /* store byte 0 */ |
| addi a4, a4, -1 /* decrement n */ |
| beqz a4, .Lret /* if n is zero */ |
| addi a10, a10, 1 /* advance dst pointer */ |
| beqz a8, .Lfill /* if byte 0 is zero */ |
| bbci.l a3, 1, .Lsrcaligned /* if src is now word-aligned */ |
| |
| .Lsrc2mod4: /* src address is 2 mod 4 */ |
| l8ui a8, a3, 0 /* get byte 0 */ |
| addi a4, a4, -1 /* decrement n */ |
| s8i a8, a10, 0 /* store byte 0 */ |
| beqz a4, .Lret /* if n is zero */ |
| addi a10, a10, 1 /* advance dst pointer */ |
| beqz a8, .Lfill /* if byte 0 is zero */ |
| l8ui a8, a3, 1 /* get byte 0 */ |
| addi a3, a3, 2 /* advance src pointer */ |
| s8i a8, a10, 0 /* store byte 0 */ |
| addi a4, a4, -1 /* decrement n */ |
| beqz a4, .Lret /* if n is zero */ |
| addi a10, a10, 1 /* advance dst pointer */ |
| bnez a8, .Lsrcaligned |
| j .Lfill |
| |
| .Lret: |
| retw |
| |
| |
| ENTRY (strncpy) |
| /* a2 = dst, a3 = src */ |
| |
| mov a10, a2 /* leave dst in return value register */ |
| beqz a4, .Lret /* if n is zero */ |
| |
| movi a11, MASK0 |
| movi a5, MASK1 |
| movi a6, MASK2 |
| movi a7, MASK3 |
| bbsi.l a3, 0, .Lsrc1mod2 |
| bbsi.l a3, 1, .Lsrc2mod4 |
| .Lsrcaligned: |
| |
| /* Check if the destination is aligned. */ |
| movi a8, 3 |
| bnone a10, a8, .Laligned |
| |
| j .Ldstunaligned |
| |
| |
| /* Fill the dst with zeros -- n is at least 1. */ |
| |
| .Lfill: |
| movi a9, 0 |
| bbsi.l a10, 0, .Lfill1mod2 |
| bbsi.l a10, 1, .Lfill2mod4 |
| .Lfillaligned: |
| blti a4, 4, .Lfillcleanup |
| |
| /* Loop filling complete words with zero. */ |
| #if XCHAL_HAVE_LOOPS |
| |
| srai a8, a4, 2 |
| loop a8, 1f |
| s32i a9, a10, 0 |
| addi a10, a10, 4 |
| |
| 1: slli a8, a8, 2 |
| sub a4, a4, a8 |
| |
| #else /* !XCHAL_HAVE_LOOPS */ |
| |
| 1: s32i a9, a10, 0 |
| addi a10, a10, 4 |
| addi a4, a4, -4 |
| bgei a4, 4, 1b |
| |
| #endif /* !XCHAL_HAVE_LOOPS */ |
| |
| beqz a4, 2f |
| |
| .Lfillcleanup: |
| /* Fill leftover (1 to 3) bytes with zero. */ |
| s8i a9, a10, 0 /* store byte 0 */ |
| addi a4, a4, -1 /* decrement n */ |
| addi a10, a10, 1 |
| bnez a4, .Lfillcleanup |
| |
| 2: retw |
| |
| .Lfill1mod2: /* dst address is odd */ |
| s8i a9, a10, 0 /* store byte 0 */ |
| addi a4, a4, -1 /* decrement n */ |
| beqz a4, 2b /* if n is zero */ |
| addi a10, a10, 1 /* advance dst pointer */ |
| bbci.l a10, 1, .Lfillaligned /* if dst is now word-aligned */ |
| |
| .Lfill2mod4: /* dst address is 2 mod 4 */ |
| s8i a9, a10, 0 /* store byte 0 */ |
| addi a4, a4, -1 /* decrement n */ |
| beqz a4, 2b /* if n is zero */ |
| s8i a9, a10, 1 /* store byte 1 */ |
| addi a4, a4, -1 /* decrement n */ |
| beqz a4, 2b /* if n is zero */ |
| addi a10, a10, 2 /* advance dst pointer */ |
| j .Lfillaligned |
| |
| |
| /* dst is word-aligned; src is word-aligned; n is at least 1. */ |
| |
| .align 4 |
| /* (2 mod 4) alignment for loop instruction */ |
| .Laligned: |
| #if XCHAL_HAVE_LOOPS |
| _movi.n a8, 0 /* set up for the maximum loop count */ |
| loop a8, 1f /* loop forever (almost anyway) */ |
| blti a4, 5, .Ldstunaligned /* n is near limit; do one at a time */ |
| l32i a8, a3, 0 /* get word from src */ |
| addi a3, a3, 4 /* advance src pointer */ |
| bnone a8, a11, .Lz0 /* if byte 0 is zero */ |
| bnone a8, a5, .Lz1 /* if byte 1 is zero */ |
| bnone a8, a6, .Lz2 /* if byte 2 is zero */ |
| s32i a8, a10, 0 /* store word to dst */ |
| addi a4, a4, -4 /* decrement n */ |
| addi a10, a10, 4 /* advance dst pointer */ |
| bnone a8, a7, .Lfill /* if byte 3 is zero */ |
| 1: |
| |
| #else /* !XCHAL_HAVE_LOOPS */ |
| |
| 1: blti a4, 5, .Ldstunaligned /* n is near limit; do one at a time */ |
| l32i a8, a3, 0 /* get word from src */ |
| addi a3, a3, 4 /* advance src pointer */ |
| bnone a8, a11, .Lz0 /* if byte 0 is zero */ |
| bnone a8, a5, .Lz1 /* if byte 1 is zero */ |
| bnone a8, a6, .Lz2 /* if byte 2 is zero */ |
| s32i a8, a10, 0 /* store word to dst */ |
| addi a4, a4, -4 /* decrement n */ |
| addi a10, a10, 4 /* advance dst pointer */ |
| bany a8, a7, 1b /* no zeroes */ |
| #endif /* !XCHAL_HAVE_LOOPS */ |
| |
| j .Lfill |
| |
| .Lz0: /* Byte 0 is zero. */ |
| #ifdef __XTENSA_EB__ |
| movi a8, 0 |
| #endif |
| s8i a8, a10, 0 |
| addi a4, a4, -1 /* decrement n */ |
| addi a10, a10, 1 /* advance dst pointer */ |
| j .Lfill |
| |
| .Lz1: /* Byte 1 is zero. */ |
| #ifdef __XTENSA_EB__ |
| extui a8, a8, 16, 16 |
| #endif |
| s16i a8, a10, 0 |
| addi a4, a4, -2 /* decrement n */ |
| addi a10, a10, 2 /* advance dst pointer */ |
| j .Lfill |
| |
| .Lz2: /* Byte 2 is zero. */ |
| #ifdef __XTENSA_EB__ |
| extui a8, a8, 16, 16 |
| #endif |
| s16i a8, a10, 0 |
| movi a8, 0 |
| s8i a8, a10, 2 |
| addi a4, a4, -3 /* decrement n */ |
| addi a10, a10, 3 /* advance dst pointer */ |
| j .Lfill |
| |
| .align 4 |
| /* (2 mod 4) alignment for loop instruction */ |
| .Ldstunaligned: |
| |
| #if XCHAL_HAVE_LOOPS |
| _movi.n a8, 0 /* set up for the maximum loop count */ |
| loop a8, 2f /* loop forever (almost anyway) */ |
| #endif |
| 1: l8ui a8, a3, 0 |
| addi a3, a3, 1 |
| s8i a8, a10, 0 |
| addi a4, a4, -1 |
| beqz a4, 3f |
| addi a10, a10, 1 |
| #if XCHAL_HAVE_LOOPS |
| beqz a8, 2f |
| #else |
| bnez a8, 1b |
| #endif |
| 2: j .Lfill |
| |
| 3: retw |
| |
| libc_hidden_def (strncpy) |