Some architectures need __clzsi2() or __clzdi2() for __builtin_clz and It causes build failure. They can be implemented using the fls() and overridden by linking arch-specific versions may not be implemented yet. Reference: https://lkml.org/lkml/2013/4/18/603 Reported-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> Signed-off-by: Chanho Min <chanho.min@xxxxxxx> --- lib/Makefile | 2 +- lib/clz.c | 36 ++++++++++++++++++++++++++++++++++++ 2 files changed, 37 insertions(+), 1 deletion(-) create mode 100644 lib/clz.c diff --git a/lib/Makefile b/lib/Makefile index af79e8c..e17b3ee 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -23,7 +23,7 @@ lib-y += kobject.o klist.o obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \ bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \ - gcd.o lcm.o list_sort.o uuid.o flex_array.o \ + gcd.o lcm.o list_sort.o uuid.o flex_array.o clz.o\ bsearch.o find_last_bit.o find_next_bit.o llist.o memweight.o kfifo.o obj-y += string_helpers.o obj-$(CONFIG_TEST_STRING_HELPERS) += test-string_helpers.o diff --git a/lib/clz.c b/lib/clz.c new file mode 100644 index 0000000..5222b2d --- /dev/null +++ b/lib/clz.c @@ -0,0 +1,36 @@ +/* + * lib/clz.c + * + * Copyright (C) 2013 Chanho Min <chanho.min@xxxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * __clzsi2/_clzdi2() can be overridden by linking arch-specific versions. + */ + +#include <linux/export.h> +#include <linux/kernel.h> + +int __weak __clzsi2(int val) +{ + return BITS_PER_LONG - fls(val); +} +EXPORT_SYMBOL(__clzsi2); + +#if BITS_PER_LONG == 32 +int __weak __clzdi2(long val) +{ + return BITS_PER_LONG - fls((int)val); +} +EXPORT_SYMBOL(__clzdi2); +#elif BITS_PER_LONG == 64 +int __weak __clzdi2i(long val) +{ + return BITS_PER_LONG - fls64((u64)val); +} +EXPORT_SYMBOL(__clzdi2); +#else +#error BITS_PER_LONG not 32 or 64 +#endif -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
