newlib-cygwin/newlib/libc/stdlib/__exp10.c

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2000-02-18 03:39:52 +08:00
/*
* compute 10**x by successive squaring.
*/
#include <_ansi.h>
2008-12-11 Craig Howland <howland@LGSInnovations.com> * libc/include/sys/lock.h: Add void cast to avoid "statement has no effect" warnings from gcc. * libc/include/sys/stdio.h: Ditto. * libc/include/sys/time.h: Correct gettimeofday() prototype. * libc/stdlib/__exp10.c: Add #include "std.h" for function prototype. * libc/stdlib/__ten_mu.c: Ditto. * libc/stdlib/std.h: Correct __exp10's ANSI prototype. * libc/stdlib/ldtoa.c: Change eiisinf definition to ANSI form. (Are already others in file without _ansi method, so did not bother.) * libc/stdlib/system.c: Use _ansi forms for function prototypes and definitions. * libc/time/mktime.c: Ditto. * libc/misc/__dprintf.c: Ditto. * libc/include/stdio.h: Add function prototypes for _fgetc_r, _fgetpos_r, _fsetpos_r, _freopen_r, _rewind_r, freopen64, _freopen64_r, _funopen_r, and _fopencookie_r. * libc/include/reent.h: Add function prototype for _stat64_r, align _execve_r prototype with POSIX definition for execve. * libc/reent/execr.c: Align function prototype with POSIX definition. * libc/stdio/asniprintf.c: Add #include "local.h". * libc/stdio/vasniprintf.c: Ditto. * libc/stdio/fread.c: Remove unused variable newcount. * libc/stdio/local.h: Add function prototype for __sccl. * libc/stdio/open_memstream.c: Remove unused variable flags. * libc/stdio/vfscanf.c: Proper prototyping for ccfn, remove prototype for __sccl since now in local.h. * libc/string/memcpy.c: Add #include <string.h> (for real and for traditional synopsis), remove extraneous stddef.h and limits.h. * libc/syscalls/sysclose.c: Add #include <unistd.h>. * libc/syscalls/sysfork.c: Ditto. * libc/syscalls/sysgetpid.c: Ditto. * libc/syscalls/sysexecve.c: Add #include <unistd.h>, align function prototype with POSIX definition. * libc/syscalls/sysfstat.c: Add #include <sys/stat.h>. * libc/syscalls/sysgettod.c: Correct sys/times.h to sys/time.h. * libc/syscalls/syskill.c: Add #include <signal.h>. * libc/syscalls/syslink.c: Add #include <unistd.h>, fix prototype. * libc/syscalls/sysunlink.c: Ditto. * libc/syscalls/sysstat.c: Add #include <sys/stat.h>, fix prototype. * libc/syscalls/syswait.c: Add #include <sys/wait.h>, fix prototype.
2008-12-12 01:27:56 +08:00
#include "std.h"
2000-02-18 03:39:52 +08:00
double
_DEFUN (__exp10, (x),
unsigned x)
{
static _CONST double powtab[] =
{1.0,
10.0,
100.0,
1000.0,
10000.0};
if (x < (sizeof (powtab) / sizeof (double)))
return powtab[x];
else if (x & 1)
{
return 10.0 * __exp10 (x - 1);
}
else
{
double n = __exp10 (x / 2);
return n * n;
}
}