diff options
Diffstat (limited to 'sysdeps/libm-i387/e_exp.S')
| -rw-r--r-- | sysdeps/libm-i387/e_exp.S | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/sysdeps/libm-i387/e_exp.S b/sysdeps/libm-i387/e_exp.S index 3ed039bc87..144748e820 100644 --- a/sysdeps/libm-i387/e_exp.S +++ b/sysdeps/libm-i387/e_exp.S @@ -10,12 +10,15 @@ RCSID("$NetBSD: e_exp.S,v 1.4 1995/05/08 23:47:04 jtc Exp $") /* e^x = 2^(x * log2(e)) */ ENTRY(__ieee754_exp) fldl 4(%esp) - fxam +/* I added the following ugly construct because exp(+-Inf) resulted + in NaN. The ugliness results from the bright minds at Intel. + -- drepper@cygnus.com. */ + fxam /* Is NaN or +-Inf? */ fstsw %ax sahf - jnc .LnoInf - jp .LisInf -.LnoInf: + jnc .LnoInfNaN /* No, jump. */ + jp .LisInf /* Is +-Inf, jump. */ +.LnoInfNaN: fldl2e fmulp /* x * log2(e) */ fstl %st(1) @@ -29,7 +32,7 @@ ENTRY(__ieee754_exp) ret .LisInf: - andb $2, %ah - jz .LpInf - fldz + andb $2, %ah /* Test sign. */ + jz .LpInf /* If positive, jump. */ + fldz /* Set result to 0. */ .LpInf: ret |