d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Optimize this a bit better.

Browse Source 
Submitted by:	bde (although these aren't all of his changes)
This commit is contained in:
David Schultz 2008-01-15 23:31:24 +00:00
parent 16670d1bd1
commit a2d171e440
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=175371
1 changed files with 18 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

31
lib/msun/src/s_rintl.c
View File

@ -32,8 +32,10 @@ __FBSDID("$FreeBSD$");
#include "fpmath.h"
static const long double
shift[2]={
#define BIAS (LDBL_MAX_EXP - 1)
static const float
shift[2] = {
#if LDBL_MANT_DIG == 64
0x1.0p63, -0x1.0p63
#elif LDBL_MANT_DIG == 113
@ -51,27 +53,30 @@ rintl(long double x)
u.e = x;
if (u.bits.exp >= LDBL_MANT_DIG + LDBL_MAX_EXP - 2) {
if (u.bits.exp >= BIAS + LDBL_MANT_DIG - 1) {
/*
* The biased exponent is greater than the number of digits
* in the mantissa, so x is inf, NaN, or an integer.
*/
if (u.bits.exp == 2 * LDBL_MAX_EXP - 1)
return (x + x); /* inf or NaN */
else
return (x);
return (x);
}
sign = u.bits.sign;
/*
* The following code assumes that intermediate results are
* evaluated in long double precision. If they are evaluated in
* greater precision, double rounding will occur, and if they are
* greater precision, double rounding may occur, and if they are
* evaluated in less precision (as on i386), results will be
* wildly incorrect.
*/
sign = u.bits.sign;
u.e = shift[sign] + x;
u.e -= shift[sign];
u.bits.sign = sign;
return (u.e);
x += shift[sign];
x -= shift[sign];
/*
* If the result is +-0, then it must have the same sign as x, but
* the above calculation doesn't always give this. Fix up the sign.
*/
if (x == 0.0L)
return (sign ? -0.0L : 0.0L);
return (x);
}