Add an initial set of arm optimized string functions. These

do seem to make noticable speed improvement...
 -Erik

1 files changed, 53 insertions, 0 deletions

diff --git a/libc/string/arm/strncmp.S b/libc/string/arm/strncmp.S
new file mode 100644
index 000000000..6f478b5ed
--- /dev/null
+++ b/libc/string/arm/strncmp.S
@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2002 ARM Ltd
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the company may not be used to endorse or promote
+ *    products derived from this software without specific prior written
+ *    permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY ARM LTD ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL ARM LTD BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+ * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Adapted for uClibc from NetBSD strncmp.S, version 1.2 2003/04/05
+ * by Erik Andersen <andersen@codepoet.org>
+ */
+
+		.text
+		.global strncmp;
+		.type strncmp,%function
+		.align 4;                                                               \
+
+strncmp:
+	/* if ((len - 1) < 0) return 0 */
+	subs	r2, r2, #1
+	movmi	r0, #0
+	movmi	pc, lr
+
+	/* ip == last src address to compare */
+	add	ip, r0, r2
+1:
+	ldrb	r2, [r0], #1
+	ldrb	r3, [r1], #1
+	cmp	ip, r0
+	cmpcs	r2, #1
+	cmpcs	r2, r3
+	beq	1b
+	sub	r0, r2, r3
+	mov	pc, lr