| 0,0 → 1,47 |
|---|
| /* |
| * ==================================================== |
| * Copyright (C) 1998, 2002 by Red Hat Inc. All rights reserved. |
| * |
| * Permission to use, copy, modify, and distribute this |
| * software is freely granted, provided that this notice |
| * is preserved. |
| * ==================================================== |
| */ |
| |
| #if !defined(_SOFT_FLOAT) |
| |
| /* |
| Fast version of exp using Intel float instructions. |
| |
| float _f_expf (float x); |
| |
| Function computes e ** x. The following special cases exist: |
| 1. if x is 0.0 ==> return 1.0 |
| 2. if x is infinity ==> return infinity |
| 3. if x is -infinity ==> return 0.0 |
| 4. if x is NaN ==> return x |
| There is no error checking or setting of errno. |
| */ |
| |
| |
| #include <math.h> |
| #include <ieeefp.h> |
| #include "f_math.h" |
| |
| float _f_expf (float x) |
| { |
| if (check_finitef(x)) |
| { |
| float result; |
| asm ("fldl2e; fmulp; fld %%st; frndint; fsub %%st,%%st(1); fxch;" \ |
| "fchs; f2xm1; fld1; faddp; fxch; fld1; fscale; fstp %%st(1); fmulp" : |
| "=t"(result) : "0"(x)); |
| return result; |
| } |
| else if (x == -infinityf()) |
| return 0.0; |
| |
| return x; |
| } |
| |
| #endif |