diff options
Diffstat (limited to 'libc/sysdeps/ieee754/dbl-64/e_pow.c')
| -rw-r--r-- | libc/sysdeps/ieee754/dbl-64/e_pow.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/libc/sysdeps/ieee754/dbl-64/e_pow.c b/libc/sysdeps/ieee754/dbl-64/e_pow.c index 28435fd36..f668b4b5f 100644 --- a/libc/sysdeps/ieee754/dbl-64/e_pow.c +++ b/libc/sysdeps/ieee754/dbl-64/e_pow.c @@ -1,7 +1,7 @@ /* * IBM Accurate Mathematical Library * written by International Business Machines Corp. - * Copyright (C) 2001, 2002, 2004, 2011 Free Software Foundation + * Copyright (C) 2001-2012 Free Software Foundation * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published by @@ -41,6 +41,7 @@ #include "MathLib.h" #include "upow.tbl" #include "math_private.h" +#include <fenv.h> #ifndef SECTION # define SECTION @@ -84,6 +85,11 @@ __ieee754_pow(double x, double y) { (u.i[HIGH_HALF]==0 && u.i[LOW_HALF]!=0)) && /* 2^-1023< x<= 2^-1023 * 0x1.0000ffffffff */ (v.i[HIGH_HALF]&0x7fffffff) < 0x4ff00000) { /* if y<-1 or y>1 */ + fenv_t env; + double retval; + + libc_feholdexcept_setround (&env, FE_TONEAREST); + z = log1(x,&aa,&error); /* x^y =e^(y log (X)) */ t = y*134217729.0; y1 = t - (t-y); @@ -97,7 +103,10 @@ __ieee754_pow(double x, double y) { a2 = (a-a1)+aa; error = error*ABS(y); t = __exp1(a1,a2,1.9e16*error); /* return -10 or 0 if wasn't computed exactly */ - return (t>0)?t:power1(x,y); + retval = (t>0)?t:power1(x,y); + + libc_feupdateenv (&env); + return retval; } if (x == 0) { |