[ARM] Factor out the thumb1 -Os implementation.

The patch moves the inline ASM thumb1 -O2 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

diff --git a/newlib/ChangeLog b/newlib/ChangeLog
index 44dfdcdcea64919888353870a00ea1f102a39c4e..f2a30a11190354b13bfb67c65db8a96a48b17de6 100644 (file)
--- a/newlib/ChangeLog
+++ b/newlib/ChangeLog
@@ -1,3 +1,9 @@
+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.
+
 2015-11-13  Marcus Shawcroft  <marcus.shawcroft@arm.com>
 
        * libc/machine/arm/Makefile.am: Adding strlen.S.

diff --git a/newlib/libc/machine/arm/strlen-stub.c b/newlib/libc/machine/arm/strlen-stub.c
index f75ee48d00253851c408b6bac8848e77d79da751..d77c7fc5b1dd55a0e2327b51c2f60af4c923cd01 100644 (file)
--- a/newlib/libc/machine/arm/strlen-stub.c
+++ b/newlib/libc/machine/arm/strlen-stub.c
@@ -33,20 +33,7 @@
 
 #if defined __OPTIMIZE_SIZE__ || defined PREFER_SIZE_OVER_SPEED
 #if defined __thumb__ && !defined __thumb2__
-size_t
-strlen (const char* str)
-{
-  int scratch;
-  size_t len;
-  asm ("mov    %0, #0\n"
-       "1:\n\t"
-       "ldrb   %1, [%2, %0]\n\t"
-       "add    %0, %0, #1\n\t"
-       "cmp    %1, #0\n\t"
-       "bne    1b"
-       : "=&r" (len), "=&r" (scratch) : "r" (str) : "memory", "cc");
-  return len - 1;
-}
+/* Implemented in strlen.S.  */
 
 #else
 size_t

diff --git a/newlib/libc/machine/arm/strlen-thumb1-Os.S b/newlib/libc/machine/arm/strlen-thumb1-Os.S
new file mode 100644 (file)
index 0000000..4b50430
--- /dev/null
+++ b/newlib/libc/machine/arm/strlen-thumb1-Os.S
@@ -0,0 +1,50 @@
+/* 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   armv4t
+       .eabi_attribute Tag_also_compatible_with, "\006\013" /* ARMv6-M.  */
+       .eabi_attribute Tag_ARM_ISA_use, 0
+       .thumb
+       .syntax unified
+
+def_fn strlen p2align=1
+       movs    r3, #0
+1:
+       ldrb    r2, [r0, r3]
+       adds    r3, r3, #1
+       cmp     r2, #0
+       bne     1b
+       subs    r0, r3, #1
+       bx      lr
+       .size   strlen, . - strlen

diff --git a/newlib/libc/machine/arm/strlen.S b/newlib/libc/machine/arm/strlen.S
index b9fb861840fc3720c6fad58728f8376d6fa4a886..ec61ae26f48e1fbe692f204018b6cce8966c50bf 100644 (file)
--- a/newlib/libc/machine/arm/strlen.S
+++ b/newlib/libc/machine/arm/strlen.S
@@ -28,7 +28,7 @@
 
 #if defined __OPTIMIZE_SIZE__ || defined PREFER_SIZE_OVER_SPEED
 #if defined __thumb__ && !defined __thumb2__
-  /* Implemented in strlen-stub.c.  */
+#include "strlen-thumb1-Os.S"
 
 #else
   /* Implemented in strlen-stub.c.  */