On Mon, Apr 22, 2013 at 11:22 AM, Chanho Min <chanho.min@xxxxxxx> wrote: >>> +#define HTYPE const u8* >>> + >>> +#ifdef __BIG_ENDIAN >>> +#define LZ4_NBCOMMONBYTES(val) (__builtin_clz(val) >> 3) >>> +#else >>> +#define LZ4_NBCOMMONBYTES(val) (__builtin_ctz(val) >> 3) >>> +#endif >> >>It seems at least m68k and sparc don't have the __builtin_clz() functions: >> >>m68k-allmodconfig (http://kisskb.ellerman.id.au/kisskb/buildresult/8572593/): >> >>ERROR: "__clzsi2" [lib/lz4/lz4hc_compress.ko] undefined! >>ERROR: "__clzsi2" [lib/lz4/lz4_compress.ko] undefined! > > gcc seems to define __builtin_clz as __clzsi2 in some architecture. > But, kernel doesn't link libgcc.a. > If kernel should use gcc's built-in function without libgcc.a, > do we need to port __clzsi2 to 'arch/*/lib/*'? That's another option. So far no one used __builtin_c[lt]z in generic code. We always used __fls and __ffs. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- 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
