diff options
author | Marcus Shawcroft <marcus.shawcroft@arm.com> | 2015-11-13 17:26:22 +0300 |
---|---|---|
committer | Marcus Shawcroft <marcus.shawcroft@arm.com> | 2015-11-23 18:21:47 +0300 |
commit | dc38827570d90b048eae55f0a2f21b5c5ca0d79b (patch) | |
tree | bba7c2ba01719872300f2a1c332b0a696367bbe9 /newlib/libc/machine | |
parent | c70d8f454a3639602296f57e247013e4c82a4857 (diff) |
[ARM] Factor out the thumb2 -Os implementation.
The 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
Diffstat (limited to 'newlib/libc/machine')
-rw-r--r-- | newlib/libc/machine/arm/strlen-stub.c | 14 | ||||
-rw-r--r-- | newlib/libc/machine/arm/strlen-thumb2-Os.S | 54 | ||||
-rw-r--r-- | newlib/libc/machine/arm/strlen.S | 2 |
3 files changed, 57 insertions, 13 deletions
diff --git a/newlib/libc/machine/arm/strlen-stub.c b/newlib/libc/machine/arm/strlen-stub.c index d77c7fc5b..97500e0e8 100644 --- a/newlib/libc/machine/arm/strlen-stub.c +++ b/newlib/libc/machine/arm/strlen-stub.c @@ -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 */ diff --git a/newlib/libc/machine/arm/strlen-thumb2-Os.S b/newlib/libc/machine/arm/strlen-thumb2-Os.S new file mode 100644 index 000000000..961f41a0a --- /dev/null +++ b/newlib/libc/machine/arm/strlen-thumb2-Os.S @@ -0,0 +1,54 @@ +/* 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. */ + +#include "acle-compat.h" + + .macro def_fn f p2align=0 + .text + .p2align \p2align + .global \f + .type \f, %function +\f: + .endm + +#if __ARM_ARCH_ISA_THUMB >= 2 && __ARM_ARCH >= 7 + .arch armv7 +#else + .arch armv6t2 +#endif + .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 diff --git a/newlib/libc/machine/arm/strlen.S b/newlib/libc/machine/arm/strlen.S index ec61ae26f..e0dd122b5 100644 --- a/newlib/libc/machine/arm/strlen.S +++ b/newlib/libc/machine/arm/strlen.S @@ -31,7 +31,7 @@ #include "strlen-thumb1-Os.S" #else - /* Implemented in strlen-stub.c. */ +#include "strlen-thumb2-Os.S" #endif |