@@ -1,5 +1,11 @@
2015-11-13 Marcus Shawcroft <marcus.shawcroft@arm.com>
+ * libc/machine/arm/strlen-stub.c: Move T2 -O2 implementation to...
+ * libc/machine/arm/strlen-thumb2-Os.S: New file.
+ * libc/machine/arm/strlen.S: Include strlen-thumb2-Os.S.
+
+2015-11-13 Marcus Shawcroft <marcus.shawcroft@arm.com>
+
* libc/machine/arm/strlen-stub.c: Move T1 -O2 implementation to...
* libc/machine/arm/strlen-thumb1-Os.S: New file.
* libc/machine/arm/strlen.S: Include strlen-thumb1-Os.S.
@@ -36,18 +36,8 @@
/* Implemented in strlen.S. */
#else
-size_t
-strlen (const char* str)
-{
- int scratch;
- const char* end;
- asm ("1:\n\t"
- "ldrb %1, [%0], #1\n\t"
- "cmp %1, #0\n\t"
- "bne 1b"
- : "=&r" (end), "=&r" (scratch) : "0" (str) : "memory", "cc");
- return end - str - 1;
-}
+/* Implemented in strlen.S. */
+
#endif
#else /* defined __OPTIMIZE_SIZE__ || defined PREFER_SIZE_OVER_SPEED */
new file mode 100644
@@ -0,0 +1,48 @@
+/* Copyright (c) 2015 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:
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ * 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.
+ * Neither the name of the Linaro nor the
+ names of its contributors may be used to endorse or promote products
+ derived from this software without specific prior written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ "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 THE COPYRIGHT
+ HOLDER OR CONTRIBUTORS 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. */
+
+ .macro def_fn f p2align=0
+ .text
+ .p2align \p2align
+ .global \f
+ .type \f, %function
+\f:
+ .endm
+
+ .arch armv6t2
+ .eabi_attribute Tag_ARM_ISA_use, 0
+ .thumb
+ .syntax unified
+
+def_fn strlen p2align=1
+ mov r3, r0
+1: ldrb.w r2, [r3], #1
+ cmp r2, #0
+ bne 1b
+ subs r0, r3, r0
+ subs r0, #1
+ bx lr
+ .size strlen, . - strlen
@@ -31,7 +31,7 @@
#include "strlen-thumb1-Os.S"
#else
- /* Implemented in strlen-stub.c. */
+#include "strlen-thumb2-Os.S"
#endif
--
1.9.1
This patch moves the inline ASM thumb2 -Os implementation out into its own .S file. Tested by building newlib and comparing libc.a binaries before and after for all permutations of: Architectures: armv4 armv4t armv5 armv5t armv5te armv6 armv6j armv6k armv6z armv6kz armv6t2 armv6-m armv6s-m armv7 armv7-a armv7ve armv7-r armv7-m armv7e-m armv8-a iwmmxt iwmmxt2 ISAs: thumb arm Optimization Levels: Os O2 Excluding: armv6s-m -mthumb armv6-m -mthumb armv6zk -mthumb armv6z -mthumb armv6k -mthumb armv6j -mthumb OK? /Marcus * libc/machine/arm/strlen-stub.c: Move T2 -O2 implementation to... * libc/machine/arm/strlen-thumb2-Os.S: New file. * libc/machine/arm/strlen.S: Include strlen-thumb2-Os.S.