ligd 7fc03e0084 lib: generic optimization for constant divisor on 32-bit machines ... 64-by-32-bit divisions are prominent in the NuttX, even on 32-bit machines. Luckily, many of them use a constant divisor that allows for a much faster multiplication by the divisor's reciprocal. The compiler already performs this optimization when compiling a 32-by-32 division with a constant divisor. Unfortunately, on 32-bit machines, gcc does not optimize 64-by-32 divisions in that case, except for constant divisors that happen to be a power of 2. Let's avoid the slow path whenever the divisor is constant by manually computing the reciprocal ourselves and performing the multiplication inline. In most cases, this improves performance of 64-by-32 divisions by about two orders of magnitude compared to the __div64_32() fallback, especially on architectures lacking a native div instruction. Signed-off-by: ligd <liguiding1@xiaomi.com>		2024-09-12 18:14:39 +08:00
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android
arpa
crypto	nuttx/crypto: export Diffie-Hellman algorithm	2024-09-09 23:55:33 +08:00
cxx	add rint and expm1 function to cmath from libm	2024-07-12 12:05:54 +08:00
net	netlib/route: add length for add/del route-func to reduce caller stack usage	2024-08-26 01:54:10 +08:00
netinet	Expose IPTOS_xxx to the application layer	2024-09-12 17:15:31 +08:00
netpacket	can: Merge netpacket/can.h into nuttx/can.h	2024-08-26 05:05:31 -04:00
nuttx	lib: generic optimization for constant divisor on 32-bit machines	2024-09-12 18:14:39 +08:00
ssp
sys	usbdev: Add fastboot boardctl	2024-09-10 23:35:58 +08:00
.gitignore	.gitignore: add ignore	2024-03-14 22:47:55 +08:00
aio.h	aio: change aio_fildes int type	2023-09-08 00:59:31 +03:00
alloca.h	libs/alloca: add alloca implement for MSVC	2023-08-28 11:10:08 -03:00
assert.h	Restore ASSERT/VERIFY semantics	2024-09-09 15:25:04 +08:00
byteswap.h
ctype.h	Add basic support for locales in order to C++ streams to build and work for simple cases (POSIX / C locale).	2024-04-29 17:34:10 +08:00
debug.h	include/debug.h: fix _alert log level error	2024-08-24 11:20:59 +08:00
dirent.h
dlfcn.h	dlfcn: Add stub for dladdr	2024-07-26 14:39:10 -03:00
dsp.h	nuttx: resolve various 'FAR' and 'CODE' issues	2024-08-26 10:21:03 +08:00
dspb16.h	libdsp: fix gcc14 error and clean up includes	2024-06-02 09:27:36 -03:00
elf32.h	Fix and improve dynamic loader	2023-07-13 10:11:58 +08:00
elf64.h	Fix loading of ET_DYN type of shared objects	2023-09-20 09:35:28 -04:00
elf.h	coredump:support coredump aligned access registers	2024-08-12 02:02:25 +08:00
endian.h
err.h
errno.h
execinfo.h	libc/execinfo: extract a common backtrace format function	2024-06-29 22:44:39 +08:00
fcntl.h	drivers/pipes: add fcntl(F_SETPIPE_SZ/F_GETPIPE_SZ) support	2024-09-10 11:35:15 +08:00
fixedmath.h	fixedmath: add abs and sign operations	2023-10-07 21:25:56 +08:00
fnmatch.h
ftw.h
getopt.h
glob.h
grp.h
hex2bin.h	libs/libc/hex2bin: enhance 64-bit compatibility	2023-08-11 19:43:37 +08:00
iconv.h
ifaddrs.h
inttypes.h	libs/libc/inttypes: add support for imaxdiv	2024-04-23 10:26:48 -03:00
iso646.h
langinfo.h	The character U+ff0c "，" could be confused with the ASCII character U+002c ",", which is more common in source code.	2023-10-03 16:53:12 -04:00
libgen.h
libintl.h
limits.h	clock: replace all up_perf_xx with perf_xx	2023-10-02 16:11:43 +02:00
locale.h
lzf.h
malloc.h	mm: record the maximum system memory usage	2023-11-09 09:08:49 +08:00
mqueue.h	fs/mqueue: Fix the wrong field type in mq_attr as the spec and add the logical judgment to deal with the condition when mq_maxmsg or mq_msgsize is less than zero or equal to zero.	2023-08-03 03:10:56 -07:00
netdb.h
nl_types.h
nxflat.h
obstack.h
poll.h
pthread.h	pthread/realtime: export interfaces about pthread ceiling priority	2024-09-10 01:26:31 +08:00
pty.h
pwd.h	pwd: Add initial implementation of getpwent	2023-07-31 07:50:10 -07:00
regex.h
resolv.h
sched.h	sched.h: add SCHED_BATCH and SCHED_IDLE definition	2024-07-14 13:20:53 -03:00
search.h	hcreate: add alloc/free func hook for user to deallocate memory	2024-08-22 20:25:30 +08:00
semaphore.h	semaphore: export priority ceiling interfaces in semaphore	2024-09-10 01:26:31 +08:00
signal.h	sigaction: Expand si_user for non-kernel signals	2023-11-22 08:00:43 -08:00
spawn.h	libs/libc/spawn: Add minimal implementation for posix_spawnattr_destory.	2023-10-31 13:42:00 +08:00
stdbool.h	nuttx/atomic.h:Fix missing type declarations at compile time	2024-08-22 01:44:29 +08:00
stddef.h
stdint.h
stdio.h	libc: add support for open_memstream	2023-11-29 02:13:19 -08:00
stdlib.h	libc: add support for reallocarray	2024-04-17 11:36:39 -03:00
stdnoreturn.h
string.h
strings.h	nuttx: resolve various 'FAR' and 'CODE' issues	2024-08-26 10:21:03 +08:00
syscall.h
syslog.h
termios.h
threads.h	Fix typo in mtx_timedlock	2024-02-02 09:03:18 -08:00
time.h	libc:Add macro restrictions to code that uses floating point numbers	2024-08-21 13:33:45 +08:00
unistd.h	libc/sysconf: add _SC_GETPW_R_SIZE_MAX	2024-08-29 09:05:45 +08:00
utime.h
uuid.h	nuttx: fix multiple 'FAR', 'CODE' and style issues	2024-08-25 19:22:15 +08:00
wchar.h	include/wchar:Fix mbstate_t Redeclaration in MSVC	2024-08-22 01:44:29 +08:00
wctype.h