diff options
| author | bde <bde@FreeBSD.org> | 1995-04-07 23:23:27 +0000 |
|---|---|---|
| committer | bde <bde@FreeBSD.org> | 1995-04-07 23:23:27 +0000 |
| commit | 2cc0b4033dd17a9b0b6d12daf26bfb393ddc94f6 (patch) | |
| tree | 976b6d4771fce822c3f20a996c5e53a9f6c4403f /lib/msun/src/e_rem_pio2f.c | |
| parent | 07041fdd38a0577516d33c770844fec7c65e4129 (diff) | |
| download | FreeBSD-src-2cc0b4033dd17a9b0b6d12daf26bfb393ddc94f6.zip FreeBSD-src-2cc0b4033dd17a9b0b6d12daf26bfb393ddc94f6.tar.gz | |
Submitted by: J.T. Conklin <jtc@wimsey.com>
Second part of update to fdlibm 5.2: speed up argument reduction for trig
functions in the case pi/4 < |x| < 3pi/4.
Remove unused static constants ("one").
Diffstat (limited to 'lib/msun/src/e_rem_pio2f.c')
| -rw-r--r-- | lib/msun/src/e_rem_pio2f.c | 27 |
1 files changed, 26 insertions, 1 deletions
diff --git a/lib/msun/src/e_rem_pio2f.c b/lib/msun/src/e_rem_pio2f.c index eae6473..153a8c4 100644 --- a/lib/msun/src/e_rem_pio2f.c +++ b/lib/msun/src/e_rem_pio2f.c @@ -14,7 +14,7 @@ */ #ifndef lint -static char rcsid[] = "$Id: e_rem_pio2f.c,v 1.2 1994/08/18 23:05:58 jtc Exp $"; +static char rcsid[] = "$Id: e_rem_pio2f.c,v 1.1.1.1 1994/08/19 09:39:57 jkh Exp $"; #endif /* __ieee754_rem_pio2f(x,y) @@ -114,6 +114,31 @@ pio2_3t = 6.1232342629e-17; /* 0x248d3132 */ ix = hx&0x7fffffff; if(ix<=0x3f490fd8) /* |x| ~<= pi/4 , no need for reduction */ {y[0] = x; y[1] = 0; return 0;} + if(ix<0x4016cbe4) { /* |x| < 3pi/4, special case with n=+-1 */ + if(hx>0) { + z = x - pio2_1; + if((ix&0xfffffff0)!=0x3fc90fd0) { /* 24+24 bit pi OK */ + y[0] = z - pio2_1t; + y[1] = (z-y[0])-pio2_1t; + } else { /* near pi/2, use 24+24+24 bit pi */ + z -= pio2_2; + y[0] = z - pio2_2t; + y[1] = (z-y[0])-pio2_2t; + } + return 1; + } else { /* negative x */ + z = x + pio2_1; + if((ix&0xfffffff0)!=0x3fc90fd0) { /* 24+24 bit pi OK */ + y[0] = z + pio2_1t; + y[1] = (z-y[0])+pio2_1t; + } else { /* near pi/2, use 24+24+24 bit pi */ + z += pio2_2; + y[0] = z + pio2_2t; + y[1] = (z-y[0])+pio2_2t; + } + return -1; + } + } if(ix<=0x43490f80) { /* |x| ~<= 2^7*(pi/2), medium size */ t = fabsf(x); n = (int32_t) (t*invpio2+half); |
