diff options
| author | Greg Ungerer <gerg@linux-m68k.org> | 2023-11-13 23:32:09 +1000 |
|---|---|---|
| committer | Geert Uytterhoeven <geert@linux-m68k.org> | 2024-12-09 13:29:17 +0100 |
| commit | e419ddeabe7edd89650a19f411f928eea12b35b1 (patch) | |
| tree | 3479c722424ecdb4f7f5257570106c241c9f5ec2 /include/linux/libgcc.h | |
| parent | 40384c840ea1944d7c5a392e8975ed088ecf0b37 (diff) | |
m68k: Use kernel's generic muldi3 libgcc function
Use the kernels own generic lib/muldi3.c implementation of muldi3 for
68K machines. Some 68K CPUs support 64bit multiplies so move the arch
specific umul_ppmm() macro into a header file that is included by
lib/muldi3.c. That way it can take advantage of the single instruction
when available.
There does not appear to be any existing mechanism for the generic
lib/muldi3.c code to pick up an external arch definition of umul_ppmm().
Create an arch specific libgcc.h that can optionally be included by
the system include/linux/libgcc.h to allow for this.
Somewhat oddly there is also a similar definition of umul_ppmm() in
the non-architecture code in lib/crypto/mpi/longlong.h for a wide range
or machines. Its presence ends up complicating the include setup and
means not being able to use something like compiler.h instead. Actually
there is a few other defines of umul_ppmm() macros spread around in
various architectures, but not directly usable for the m68k case.
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
Link: https://lore.kernel.org/20231113133209.1367286-1-gerg@linux-m68k.org
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Diffstat (limited to 'include/linux/libgcc.h')
| -rw-r--r-- | include/linux/libgcc.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/include/linux/libgcc.h b/include/linux/libgcc.h index fc388da6a027..0d68f9d6a6a7 100644 --- a/include/linux/libgcc.h +++ b/include/linux/libgcc.h @@ -34,4 +34,8 @@ long long notrace __lshrdi3(long long u, word_type b); long long notrace __muldi3(long long u, long long v); word_type notrace __ucmpdi2(unsigned long long a, unsigned long long b); +#ifdef CONFIG_HAVE_ARCH_LIBGCC_H +#include <asm/libgcc.h> +#endif + #endif /* __ASM_LIBGCC_H */ |