1 files changed, 110 insertions, 0 deletions

diff --git a/arch/blackfin/lib/memcmp.S b/arch/blackfin/lib/memcmp.S
new file mode 100644
index 000000000000..5b9502368fc6
--- /dev/null
+++ b/arch/blackfin/lib/memcmp.S
@@ -0,0 +1,110 @@
+/*
+ * File:         arch/blackfin/lib/memcmp.S
+ * Based on:
+ * Author:
+ *
+ * Created:
+ * Description:
+ *
+ * Modified:
+ *               Copyright 2004-2006 Analog Devices Inc.
+ *
+ * Bugs:         Enter bugs at http://blackfin.uclinux.org/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <linux/linkage.h>
+
+/* int memcmp(const void *s1, const void *s2, size_t n);
+ * R0 = First Address (s1)
+ * R1 = Second Address (s2)
+ * R2 = count (n)
+ *
+ * Favours word aligned data.
+ */
+
+.text
+
+.align 2
+
+ENTRY(_memcmp)
+        I1 = P3;
+        P0 = R0;                        /* P0 = s1 address */
+        P3 = R1;                        /* P3 = s2 Address  */
+        P2 = R2 ;                       /* P2 = count */
+        CC = R2 <= 7(IU);
+        IF CC JUMP .Ltoo_small;
+        I0 = R1;                        /* s2 */
+        R1 = R1 | R0;           /* OR addresses together */
+        R1 <<= 30;              /* check bottom two bits */
+        CC =  AZ;                       /* AZ set if zero. */
+        IF !CC JUMP .Lbytes ;   /* Jump if addrs not aligned. */
+
+        P1 = P2 >> 2;           /* count = n/4 */
+        R3 =  3;
+        R2 = R2 & R3;           /* remainder */
+        P2 = R2;                        /* set remainder */
+
+        LSETUP (.Lquad_loop_s, .Lquad_loop_e) LC0=P1;
+.Lquad_loop_s:
+        MNOP || R0 = [P0++] || R1 = [I0++];
+        CC = R0 == R1;
+        IF !CC JUMP .Lquad_different;
+.Lquad_loop_e:
+        NOP;
+
+        P3 = I0;                        /* s2 */
+.Ltoo_small:
+        CC = P2 == 0;           /* Check zero count*/
+        IF CC JUMP .Lfinished;  /* very unlikely*/
+
+.Lbytes:
+        LSETUP (.Lbyte_loop_s, .Lbyte_loop_e) LC0=P2;
+.Lbyte_loop_s:
+        R1 = B[P3++](Z);        /* *s2 */
+        R0 = B[P0++](Z);        /* *s1 */
+        CC = R0 == R1;
+        IF !CC JUMP .Ldifferent;
+.Lbyte_loop_e:
+        NOP;
+
+.Ldifferent:
+        R0 = R0 - R1;
+        P3 = I1;
+        RTS;
+
+.Lquad_different:
+        /* We've read two quads which don't match.
+         * Can't just compare them, because we're
+         * a little-endian machine, so the MSBs of
+         * the regs occur at later addresses in the
+         * string.
+         * Arrange to re-read those two quads again,
+         * byte-by-byte.
+         */
+        P0 += -4;               /* back up to the start of the */
+        P3 = I0;                /* quads, and increase the*/
+        P2 += 4;                /* remainder count*/
+        P3 += -4;
+        JUMP .Lbytes;
+
+.Lfinished:
+        R0 = 0;
+        P3 = I1;
+        RTS;
+
+.size _memcmp,.-_memcmp