diff options
Diffstat (limited to 'src/math/atanl.c')
| -rw-r--r-- | src/math/atanl.c | 33 |
1 files changed, 13 insertions, 20 deletions
diff --git a/src/math/atanl.c b/src/math/atanl.c index 33ecff0d..6a480a7a 100644 --- a/src/math/atanl.c +++ b/src/math/atanl.c @@ -22,11 +22,6 @@ long double atanl(long double x) return atan(x); } #elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384 -#include "__invtrigl.h" - -#define ATAN_CONST (BIAS + 65) /* 2**65 */ -#define ATAN_LINEAR (BIAS - 32) /* 2**-32 */ -static const long double huge = 1.0e300; static const long double atanhi[] = { 4.63647609000806116202e-01L, @@ -81,29 +76,27 @@ long double atanl(long double x) u.e = x; expsign = u.xbits.expsign; expt = expsign & 0x7fff; - if (expt >= ATAN_CONST) { /* if |x| is large, atan(x)~=pi/2 */ - if (expt == BIAS + LDBL_MAX_EXP && + if (expt >= 0x3fff + 65) { /* if |x| is large, atan(x)~=pi/2 */ + if (expt == 0x7fff && ((u.bits.manh&~LDBL_NBIT)|u.bits.manl)!=0) /* NaN */ return x+x; - if (expsign > 0) - return atanhi[3]+atanlo[3]; - else - return -atanhi[3]-atanlo[3]; + z = atanhi[3] + 0x1p-1000; + return expsign < 0 ? -z : z; } /* Extract the exponent and the first few bits of the mantissa. */ /* XXX There should be a more convenient way to do this. */ - expman = (expt << 8) | ((u.bits.manh >> (MANH_SIZE - 9)) & 0xff); - if (expman < ((BIAS - 2) << 8) + 0xc0) { /* |x| < 0.4375 */ - if (expt < ATAN_LINEAR) { /* if |x| is small, atanl(x)~=x */ - /* raise inexact */ - if (huge+x > 1.0) - return x; + expman = (expt << 8) | ((u.bits.manh >> (LDBL_MANH_SIZE - 9)) & 0xff); + if (expman < ((0x3fff - 2) << 8) + 0xc0) { /* |x| < 0.4375 */ + if (expt < 0x3fff - 32) { /* if |x| is small, atanl(x)~=x */ + /* raise inexact if x!=0 */ + FORCE_EVAL(x + 0x1p1000); + return x; } id = -1; } else { x = fabsl(x); - if (expman < (BIAS << 8) + 0x30) { /* |x| < 1.1875 */ - if (expman < ((BIAS - 1) << 8) + 0x60) { /* 7/16 <= |x| < 11/16 */ + if (expman < (0x3fff << 8) + 0x30) { /* |x| < 1.1875 */ + if (expman < ((0x3fff - 1) << 8) + 0x60) { /* 7/16 <= |x| < 11/16 */ id = 0; x = (2.0*x-1.0)/(2.0+x); } else { /* 11/16 <= |x| < 19/16 */ @@ -111,7 +104,7 @@ long double atanl(long double x) x = (x-1.0)/(x+1.0); } } else { - if (expman < ((BIAS + 1) << 8) + 0x38) { /* |x| < 2.4375 */ + if (expman < ((0x3fff + 1) << 8) + 0x38) { /* |x| < 2.4375 */ id = 2; x = (x-1.5)/(1.0+1.5*x); } else { /* 2.4375 <= |x| < 2^ATAN_CONST */ |