[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit
Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/build/uClibc/libc/string/xtensa/strcmp.S b/ap/build/uClibc/libc/string/xtensa/strcmp.S
new file mode 100644
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--- /dev/null
+++ b/ap/build/uClibc/libc/string/xtensa/strcmp.S
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+/* Optimized strcmp 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>
+#include <features.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
+
+#define MASK4 0x40404040
+
+ .literal .Lmask0, MASK0
+ .literal .Lmask1, MASK1
+ .literal .Lmask2, MASK2
+ .literal .Lmask3, MASK3
+ .literal .Lmask4, MASK4
+
+ .text
+ENTRY (strcmp)
+ /* a2 = s1, a3 = s2 */
+
+ l8ui a8, a2, 0 /* byte 0 from s1 */
+ l8ui a9, a3, 0 /* byte 0 from s2 */
+ movi a10, 3 /* mask */
+ bne a8, a9, .Lretdiff
+
+ or a11, a2, a3
+ bnone a11, a10, .Laligned
+
+ xor a11, a2, a3 /* compare low two bits of s1 and s2 */
+ bany a11, a10, .Lunaligned /* if they have different alignment */
+
+ /* s1/s2 are not word-aligned. */
+ addi a2, a2, 1 /* advance s1 */
+ beqz a8, .Leq /* bytes equal, if zero, strings are equal */
+ addi a3, a3, 1 /* advance s2 */
+ bnone a2, a10, .Laligned /* if s1/s2 now aligned */
+ l8ui a8, a2, 0 /* byte 1 from s1 */
+ l8ui a9, a3, 0 /* byte 1 from s2 */
+ addi a2, a2, 1 /* advance s1 */
+ bne a8, a9, .Lretdiff /* if different, return difference */
+ beqz a8, .Leq /* bytes equal, if zero, strings are equal */
+ addi a3, a3, 1 /* advance s2 */
+ bnone a2, a10, .Laligned /* if s1/s2 now aligned */
+ l8ui a8, a2, 0 /* byte 2 from s1 */
+ l8ui a9, a3, 0 /* byte 2 from s2 */
+ addi a2, a2, 1 /* advance s1 */
+ bne a8, a9, .Lretdiff /* if different, return difference */
+ beqz a8, .Leq /* bytes equal, if zero, strings are equal */
+ addi a3, a3, 1 /* advance s2 */
+ j .Laligned
+
+/* s1 and s2 have different alignment.
+
+ If the zero-overhead loop option is available, use an (almost)
+ infinite zero-overhead loop with conditional exits so we only pay
+ for taken branches when exiting the loop.
+
+ Note: It is important for this unaligned case to come before the
+ code for aligned strings, because otherwise some of the branches
+ above cannot reach and have to be transformed to branches around
+ jumps. The unaligned code is smaller and the branches can reach
+ over it. */
+
+ .align 4
+ /* (2 mod 4) alignment for loop instruction */
+.Lunaligned:
+#if XCHAL_HAVE_LOOPS
+ _movi.n a8, 0 /* set up for the maximum loop count */
+ loop a8, .Lretdiff /* loop forever (almost anyway) */
+#endif
+.Lnextbyte:
+ l8ui a8, a2, 0
+ l8ui a9, a3, 0
+ addi a2, a2, 1
+ bne a8, a9, .Lretdiff
+ addi a3, a3, 1
+#if XCHAL_HAVE_LOOPS
+ beqz a8, .Lretdiff
+#else
+ bnez a8, .Lnextbyte
+#endif
+.Lretdiff:
+ sub a2, a8, a9
+ retw
+
+/* s1 is word-aligned; s2 is word-aligned.
+
+ If the zero-overhead loop option is available, use an (almost)
+ infinite zero-overhead loop with conditional exits so we only pay
+ for taken branches when exiting the loop. */
+
+/* New algorithm, relying on the fact that all normal ASCII is between
+ 32 and 127.
+
+ Rather than check all bytes for zero:
+ Take one word (4 bytes). Call it w1.
+ Shift w1 left by one into w1'.
+ Or w1 and w1'. For all normal ASCII bit 6 will be 1; for zero it won't.
+ Check that all 4 bit 6's (one for each byte) are one:
+ If they are, we are definitely not done.
+ If they are not, we are probably done, but need to check for zero. */
+
+ .align 4
+#if XCHAL_HAVE_LOOPS
+.Laligned:
+ .begin no-transform
+ l32r a4, .Lmask0 /* mask for byte 0 */
+ l32r a7, .Lmask4
+ /* Loop forever. (a4 is more than than the maximum number
+ of iterations) */
+ loop a4, .Laligned_done
+
+ /* First unrolled loop body. */
+ l32i a8, a2, 0 /* get word from s1 */
+ l32i a9, a3, 0 /* get word from s2 */
+ slli a5, a8, 1
+ bne a8, a9, .Lwne2
+ or a9, a8, a5
+ bnall a9, a7, .Lprobeq
+
+ /* Second unrolled loop body. */
+ l32i a8, a2, 4 /* get word from s1+4 */
+ l32i a9, a3, 4 /* get word from s2+4 */
+ slli a5, a8, 1
+ bne a8, a9, .Lwne2
+ or a9, a8, a5
+ bnall a9, a7, .Lprobeq2
+
+ addi a2, a2, 8 /* advance s1 pointer */
+ addi a3, a3, 8 /* advance s2 pointer */
+.Laligned_done:
+ or a1, a1, a1 /* nop */
+
+.Lprobeq2:
+ /* Adjust pointers to account for the loop unrolling. */
+ addi a2, a2, 4
+ addi a3, a3, 4
+
+#else /* !XCHAL_HAVE_LOOPS */
+
+.Laligned:
+ movi a4, MASK0 /* mask for byte 0 */
+ movi a7, MASK4
+ j .Lfirstword
+.Lnextword:
+ addi a2, a2, 4 /* advance s1 pointer */
+ addi a3, a3, 4 /* advance s2 pointer */
+.Lfirstword:
+ l32i a8, a2, 0 /* get word from s1 */
+ l32i a9, a3, 0 /* get word from s2 */
+ slli a5, a8, 1
+ bne a8, a9, .Lwne2
+ or a9, a8, a5
+ ball a9, a7, .Lnextword
+#endif /* !XCHAL_HAVE_LOOPS */
+
+ /* align (0 mod 4) */
+.Lprobeq:
+ /* Words are probably equal, but check for sure.
+ If not, loop over the rest of string using normal algorithm. */
+
+ bnone a8, a4, .Leq /* if byte 0 is zero */
+ l32r a5, .Lmask1 /* mask for byte 1 */
+ l32r a6, .Lmask2 /* mask for byte 2 */
+ bnone a8, a5, .Leq /* if byte 1 is zero */
+ l32r a7, .Lmask3 /* mask for byte 3 */
+ bnone a8, a6, .Leq /* if byte 2 is zero */
+ bnone a8, a7, .Leq /* if byte 3 is zero */
+ addi.n a2, a2, 4 /* advance s1 pointer */
+ addi.n a3, a3, 4 /* advance s2 pointer */
+#if XCHAL_HAVE_LOOPS
+
+ /* align (1 mod 4) */
+ loop a4, .Leq /* loop forever (a4 is bigger than max iters) */
+ .end no-transform
+
+ l32i a8, a2, 0 /* get word from s1 */
+ l32i a9, a3, 0 /* get word from s2 */
+ addi a2, a2, 4 /* advance s1 pointer */
+ bne a8, a9, .Lwne
+ bnone a8, a4, .Leq /* if byte 0 is zero */
+ bnone a8, a5, .Leq /* if byte 1 is zero */
+ bnone a8, a6, .Leq /* if byte 2 is zero */
+ bnone a8, a7, .Leq /* if byte 3 is zero */
+ addi a3, a3, 4 /* advance s2 pointer */
+
+#else /* !XCHAL_HAVE_LOOPS */
+
+ j .Lfirstword2
+.Lnextword2:
+ addi a3, a3, 4 /* advance s2 pointer */
+.Lfirstword2:
+ l32i a8, a2, 0 /* get word from s1 */
+ l32i a9, a3, 0 /* get word from s2 */
+ addi a2, a2, 4 /* advance s1 pointer */
+ bne a8, a9, .Lwne
+ bnone a8, a4, .Leq /* if byte 0 is zero */
+ bnone a8, a5, .Leq /* if byte 1 is zero */
+ bnone a8, a6, .Leq /* if byte 2 is zero */
+ bany a8, a7, .Lnextword2 /* if byte 3 is zero */
+#endif /* !XCHAL_HAVE_LOOPS */
+
+ /* Words are equal; some byte is zero. */
+.Leq: movi a2, 0 /* return equal */
+ retw
+
+.Lwne2: /* Words are not equal. On big-endian processors, if none of the
+ bytes are zero, the return value can be determined by a simple
+ comparison. */
+#ifdef __XTENSA_EB__
+ or a10, a8, a5
+ bnall a10, a7, .Lsomezero
+ bgeu a8, a9, .Lposreturn
+ movi a2, -1
+ retw
+.Lposreturn:
+ movi a2, 1
+ retw
+.Lsomezero: /* There is probably some zero byte. */
+#endif /* __XTENSA_EB__ */
+.Lwne: /* Words are not equal. */
+ xor a2, a8, a9 /* get word with nonzero in byte that differs */
+ bany a2, a4, .Ldiff0 /* if byte 0 differs */
+ movi a5, MASK1 /* mask for byte 1 */
+ bnone a8, a4, .Leq /* if byte 0 is zero */
+ bany a2, a5, .Ldiff1 /* if byte 1 differs */
+ movi a6, MASK2 /* mask for byte 2 */
+ bnone a8, a5, .Leq /* if byte 1 is zero */
+ bany a2, a6, .Ldiff2 /* if byte 2 differs */
+ bnone a8, a6, .Leq /* if byte 2 is zero */
+#ifdef __XTENSA_EB__
+.Ldiff3:
+.Ldiff2:
+.Ldiff1:
+ /* Byte 0 is equal (at least) and there is a difference before a zero
+ byte. Just subtract words to get the return value.
+ The high order equal bytes cancel, leaving room for the sign. */
+ sub a2, a8, a9
+ retw
+
+.Ldiff0:
+ /* Need to make room for the sign, so can't subtract whole words. */
+ extui a10, a8, 24, 8
+ extui a11, a9, 24, 8
+ sub a2, a10, a11
+ retw
+
+#else /* !__XTENSA_EB__ */
+ /* Little-endian is a little more difficult because can't subtract
+ whole words. */
+.Ldiff3:
+ /* Bytes 0-2 are equal; byte 3 is different.
+ For little-endian need to have a sign bit for the difference. */
+ extui a10, a8, 24, 8
+ extui a11, a9, 24, 8
+ sub a2, a10, a11
+ retw
+
+.Ldiff0:
+ /* Byte 0 is different. */
+ extui a10, a8, 0, 8
+ extui a11, a9, 0, 8
+ sub a2, a10, a11
+ retw
+
+.Ldiff1:
+ /* Byte 0 is equal; byte 1 is different. */
+ extui a10, a8, 8, 8
+ extui a11, a9, 8, 8
+ sub a2, a10, a11
+ retw
+
+.Ldiff2:
+ /* Bytes 0-1 are equal; byte 2 is different. */
+ extui a10, a8, 16, 8
+ extui a11, a9, 16, 8
+ sub a2, a10, a11
+ retw
+
+#endif /* !__XTENSA_EB */
+
+libc_hidden_def (strcmp)
+
+#ifndef __UCLIBC_HAS_LOCALE__
+strong_alias (strcmp, strcoll)
+libc_hidden_def (strcoll)
+#endif