diff options
Diffstat (limited to 'newlib/libc/machine/arm/strlen.c')
| -rw-r--r-- | newlib/libc/machine/arm/strlen.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/newlib/libc/machine/arm/strlen.c b/newlib/libc/machine/arm/strlen.c index b8de22994..7e59e755d 100644 --- a/newlib/libc/machine/arm/strlen.c +++ b/newlib/libc/machine/arm/strlen.c @@ -34,6 +34,24 @@ #if defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED) || \ (defined (__thumb__) && !defined (__thumb2__)) +# if !defined (PREFER_SIZE_OVER_SPEED) && !defined (__OPTIMIZE_SIZE__) +/* Thumb1 only variant. + If speed is preferred, the strlen() function in ../../string/strlen.c + will be used. + + Leave this field blank. So the strlen() is not defined, and this will + automatically pull in the default C definition of strlen() from + ../../string/strlen.c. No need to include this file explicitely. + The lib_a-strlen.o will not be generated, so it won't replace the default + lib_a-strlen.o which is generated by ../../string/strlen.c. See the + commands in configure.in and Makefile.am for more details. + + However, if we need to rewrite this function to be more efficient, + we can add the corresponding assembly code into this field and change + the commands in configure.in and Makefile.am to allow the corresponding + lib_a-strlen.o to be generated. +*/ +# else size_t strlen (const char* str) { @@ -43,7 +61,7 @@ strlen (const char* str) asm ("mov %0, #0\n" "1:\n\t" "ldrb %1, [%2, %0]\n\t" - "add %0, %0, #1\n\t" + "add %0, %0, #1\n\t" "cmp %1, #0\n\t" "bne 1b" : "=&r" (len), "=&r" (scratch) : "r" (str) : "memory", "cc"); @@ -58,6 +76,7 @@ strlen (const char* str) return end - str - 1; #endif } +#endif #else #if !(defined(_ISA_ARM_7) || defined(__ARM_ARCH_6T2__)) |