/* Reduce range of X and compute sin of a + da. K is the amount by which to rotate the quadrants. This allows us to use the same routine to compute cos by simply rotating the quadrants by 1. */ static inline double __always_inline reduce_and_compute (double x, unsigned int k) { double retval = 0, a, da; unsigned int n = __branred (x, &a, &da); k = (n + k) % 4; switch (k) { case 0: if (a * a < 0.01588) retval = bsloww (a, da, x, n); else retval = bsloww1 (a, da, x, n); break; case 2: if (a * a < 0.01588) retval = bsloww (-a, -da, x, n); else retval = bsloww1 (-a, -da, x, n); break; case 1: case 3: retval = bsloww2 (a, da, x, n); break; } return retval; }
/* Consolidated version of reduce_and_compute in s_sin.c that does range reduction only once and computes sin and cos together. */ static inline void __always_inline reduce_and_compute_sincos (double x, double *sinx, double *cosx) { double a, da; unsigned int n = __branred (x, &a, &da); n = n & 3; if (n == 1 || n == 2) { a = -a; da = -da; } if (n & 1) { double *temp = cosx; cosx = sinx; sinx = temp; } if (a * a < 0.01588) *sinx = bsloww (a, da, x, n); else *sinx = bsloww1 (a, da, x, n); *cosx = bsloww2 (a, da, x, n); }
double __sin(double x){ double xx,res,t,cor,y,s,c,sn,ssn,cs,ccs,xn,a,da,db,eps,xn1,xn2; #if 0 double w[2]; #endif mynumber u,v; int4 k,m,n; #if 0 int4 nn; #endif u.x = x; m = u.i[HIGH_HALF]; k = 0x7fffffff&m; /* no sign */ if (k < 0x3e500000) /* if x->0 =>sin(x)=x */ return x; /*---------------------------- 2^-26 < |x|< 0.25 ----------------------*/ else if (k < 0x3fd00000){ xx = x*x; /*Taylor series */ t = ((((s5.x*xx + s4.x)*xx + s3.x)*xx + s2.x)*xx + s1.x)*(xx*x); res = x+t; cor = (x-res)+t; return (res == res + 1.07*cor)? res : slow(x); } /* else if (k < 0x3fd00000) */ /*---------------------------- 0.25<|x|< 0.855469---------------------- */ else if (k < 0x3feb6000) { u.x=(m>0)?big.x+x:big.x-x; y=(m>0)?x-(u.x-big.x):x+(u.x-big.x); xx=y*y; s = y + y*xx*(sn3 +xx*sn5); c = xx*(cs2 +xx*(cs4 + xx*cs6)); k=u.i[LOW_HALF]<<2; sn=(m>0)?sincos.x[k]:-sincos.x[k]; ssn=(m>0)?sincos.x[k+1]:-sincos.x[k+1]; cs=sincos.x[k+2]; ccs=sincos.x[k+3]; cor=(ssn+s*ccs-sn*c)+cs*s; res=sn+cor; cor=(sn-res)+cor; return (res==res+1.025*cor)? res : slow1(x); } /* else if (k < 0x3feb6000) */ /*----------------------- 0.855469 <|x|<2.426265 ----------------------*/ else if (k < 0x400368fd ) { y = (m>0)? hp0.x-x:hp0.x+x; if (y>=0) { u.x = big.x+y; y = (y-(u.x-big.x))+hp1.x; } else { u.x = big.x-y; y = (-hp1.x) - (y+(u.x-big.x)); } xx=y*y; s = y + y*xx*(sn3 +xx*sn5); c = xx*(cs2 +xx*(cs4 + xx*cs6)); k=u.i[LOW_HALF]<<2; sn=sincos.x[k]; ssn=sincos.x[k+1]; cs=sincos.x[k+2]; ccs=sincos.x[k+3]; cor=(ccs-s*ssn-cs*c)-sn*s; res=cs+cor; cor=(cs-res)+cor; return (res==res+1.020*cor)? ((m>0)?res:-res) : slow2(x); } /* else if (k < 0x400368fd) */ /*-------------------------- 2.426265<|x|< 105414350 ----------------------*/ else if (k < 0x419921FB ) { t = (x*hpinv.x + toint.x); xn = t - toint.x; v.x = t; y = (x - xn*mp1.x) - xn*mp2.x; n =v.i[LOW_HALF]&3; da = xn*mp3.x; a=y-da; da = (y-a)-da; eps = ABS(x)*1.2e-30; switch (n) { /* quarter of unit circle */ case 0: case 2: xx = a*a; if (n) {a=-a;da=-da;} if (xx < 0.01588) { /*Taylor series */ t = (((((s5.x*xx + s4.x)*xx + s3.x)*xx + s2.x)*xx + s1.x)*a - 0.5*da)*xx+da; res = a+t; cor = (a-res)+t; cor = (cor>0)? 1.02*cor+eps : 1.02*cor -eps; return (res == res + cor)? res : sloww(a,da,x); } else { if (a>0) {m=1;t=a;db=da;} else {m=0;t=-a;db=-da;} u.x=big.x+t; y=t-(u.x-big.x); xx=y*y; s = y + (db+y*xx*(sn3 +xx*sn5)); c = y*db+xx*(cs2 +xx*(cs4 + xx*cs6)); k=u.i[LOW_HALF]<<2; sn=sincos.x[k]; ssn=sincos.x[k+1]; cs=sincos.x[k+2]; ccs=sincos.x[k+3]; cor=(ssn+s*ccs-sn*c)+cs*s; res=sn+cor; cor=(sn-res)+cor; cor = (cor>0)? 1.035*cor+eps : 1.035*cor-eps; return (res==res+cor)? ((m)?res:-res) : sloww1(a,da,x); } break; case 1: case 3: if (a<0) {a=-a;da=-da;} u.x=big.x+a; y=a-(u.x-big.x)+da; xx=y*y; k=u.i[LOW_HALF]<<2; sn=sincos.x[k]; ssn=sincos.x[k+1]; cs=sincos.x[k+2]; ccs=sincos.x[k+3]; s = y + y*xx*(sn3 +xx*sn5); c = xx*(cs2 +xx*(cs4 + xx*cs6)); cor=(ccs-s*ssn-cs*c)-sn*s; res=cs+cor; cor=(cs-res)+cor; cor = (cor>0)? 1.025*cor+eps : 1.025*cor-eps; return (res==res+cor)? ((n&2)?-res:res) : sloww2(a,da,x,n); break; } } /* else if (k < 0x419921FB ) */ /*---------------------105414350 <|x|< 281474976710656 --------------------*/ else if (k < 0x42F00000 ) { t = (x*hpinv.x + toint.x); xn = t - toint.x; v.x = t; xn1 = (xn+8.0e22)-8.0e22; xn2 = xn - xn1; y = ((((x - xn1*mp1.x) - xn1*mp2.x)-xn2*mp1.x)-xn2*mp2.x); n =v.i[LOW_HALF]&3; da = xn1*pp3.x; t=y-da; da = (y-t)-da; da = (da - xn2*pp3.x) -xn*pp4.x; a = t+da; da = (t-a)+da; eps = 1.0e-24; switch (n) { case 0: case 2: xx = a*a; if (n) {a=-a;da=-da;} if (xx < 0.01588) { /* Taylor series */ t = (((((s5.x*xx + s4.x)*xx + s3.x)*xx + s2.x)*xx + s1.x)*a - 0.5*da)*xx+da; res = a+t; cor = (a-res)+t; cor = (cor>0)? 1.02*cor+eps : 1.02*cor -eps; return (res == res + cor)? res : bsloww(a,da,x,n); } else { if (a>0) {m=1;t=a;db=da;} else {m=0;t=-a;db=-da;} u.x=big.x+t; y=t-(u.x-big.x); xx=y*y; s = y + (db+y*xx*(sn3 +xx*sn5)); c = y*db+xx*(cs2 +xx*(cs4 + xx*cs6)); k=u.i[LOW_HALF]<<2; sn=sincos.x[k]; ssn=sincos.x[k+1]; cs=sincos.x[k+2]; ccs=sincos.x[k+3]; cor=(ssn+s*ccs-sn*c)+cs*s; res=sn+cor; cor=(sn-res)+cor; cor = (cor>0)? 1.035*cor+eps : 1.035*cor-eps; return (res==res+cor)? ((m)?res:-res) : bsloww1(a,da,x,n); } break; case 1: case 3: if (a<0) {a=-a;da=-da;} u.x=big.x+a; y=a-(u.x-big.x)+da; xx=y*y; k=u.i[LOW_HALF]<<2; sn=sincos.x[k]; ssn=sincos.x[k+1]; cs=sincos.x[k+2]; ccs=sincos.x[k+3]; s = y + y*xx*(sn3 +xx*sn5); c = xx*(cs2 +xx*(cs4 + xx*cs6)); cor=(ccs-s*ssn-cs*c)-sn*s; res=cs+cor; cor=(cs-res)+cor; cor = (cor>0)? 1.025*cor+eps : 1.025*cor-eps; return (res==res+cor)? ((n&2)?-res:res) : bsloww2(a,da,x,n); break; } } /* else if (k < 0x42F00000 ) */ /* -----------------281474976710656 <|x| <2^1024----------------------------*/ else if (k < 0x7ff00000) { n = __branred(x,&a,&da); switch (n) { case 0: if (a*a < 0.01588) return bsloww(a,da,x,n); else return bsloww1(a,da,x,n); break; case 2: if (a*a < 0.01588) return bsloww(-a,-da,x,n); else return bsloww1(-a,-da,x,n); break; case 1: case 3: return bsloww2(a,da,x,n); break; } } /* else if (k < 0x7ff00000 ) */ /*--------------------- |x| > 2^1024 ----------------------------------*/ else return x / x; return 0; /* unreachable */ }
double __cos(double x) { double y,xx,res,t,cor,s,c,sn,ssn,cs,ccs,xn,a,da,db,eps,xn1,xn2; mynumber u,v; int4 k,m,n; u.x = x; m = u.i[HIGH_HALF]; k = 0x7fffffff&m; if (k < 0x3e400000 ) return 1.0; /* |x|<2^-27 => cos(x)=1 */ else if (k < 0x3feb6000 ) {/* 2^-27 < |x| < 0.855469 */ y=ABS(x); u.x = big.x+y; y = y-(u.x-big.x); xx=y*y; s = y + y*xx*(sn3 +xx*sn5); c = xx*(cs2 +xx*(cs4 + xx*cs6)); k=u.i[LOW_HALF]<<2; sn=sincos.x[k]; ssn=sincos.x[k+1]; cs=sincos.x[k+2]; ccs=sincos.x[k+3]; cor=(ccs-s*ssn-cs*c)-sn*s; res=cs+cor; cor=(cs-res)+cor; return (res==res+1.020*cor)? res : cslow2(x); } /* else if (k < 0x3feb6000) */ else if (k < 0x400368fd ) {/* 0.855469 <|x|<2.426265 */; y=hp0.x-ABS(x); a=y+hp1.x; da=(y-a)+hp1.x; xx=a*a; if (xx < 0.01588) { t = (((((s5.x*xx + s4.x)*xx + s3.x)*xx + s2.x)*xx + s1.x)*a - 0.5*da)*xx+da; res = a+t; cor = (a-res)+t; cor = (cor>0)? 1.02*cor+1.0e-31 : 1.02*cor -1.0e-31; return (res == res + cor)? res : csloww(a,da,x); } else { if (a>0) {m=1;t=a;db=da;} else {m=0;t=-a;db=-da;} u.x=big.x+t; y=t-(u.x-big.x); xx=y*y; s = y + (db+y*xx*(sn3 +xx*sn5)); c = y*db+xx*(cs2 +xx*(cs4 + xx*cs6)); k=u.i[LOW_HALF]<<2; sn=sincos.x[k]; ssn=sincos.x[k+1]; cs=sincos.x[k+2]; ccs=sincos.x[k+3]; cor=(ssn+s*ccs-sn*c)+cs*s; res=sn+cor; cor=(sn-res)+cor; cor = (cor>0)? 1.035*cor+1.0e-31 : 1.035*cor-1.0e-31; return (res==res+cor)? ((m)?res:-res) : csloww1(a,da,x); } } /* else if (k < 0x400368fd) */ else if (k < 0x419921FB ) {/* 2.426265<|x|< 105414350 */ t = (x*hpinv.x + toint.x); xn = t - toint.x; v.x = t; y = (x - xn*mp1.x) - xn*mp2.x; n =v.i[LOW_HALF]&3; da = xn*mp3.x; a=y-da; da = (y-a)-da; eps = ABS(x)*1.2e-30; switch (n) { case 1: case 3: xx = a*a; if (n == 1) {a=-a;da=-da;} if (xx < 0.01588) { t = (((((s5.x*xx + s4.x)*xx + s3.x)*xx + s2.x)*xx + s1.x)*a - 0.5*da)*xx+da; res = a+t; cor = (a-res)+t; cor = (cor>0)? 1.02*cor+eps : 1.02*cor -eps; return (res == res + cor)? res : csloww(a,da,x); } else { if (a>0) {m=1;t=a;db=da;} else {m=0;t=-a;db=-da;} u.x=big.x+t; y=t-(u.x-big.x); xx=y*y; s = y + (db+y*xx*(sn3 +xx*sn5)); c = y*db+xx*(cs2 +xx*(cs4 + xx*cs6)); k=u.i[LOW_HALF]<<2; sn=sincos.x[k]; ssn=sincos.x[k+1]; cs=sincos.x[k+2]; ccs=sincos.x[k+3]; cor=(ssn+s*ccs-sn*c)+cs*s; res=sn+cor; cor=(sn-res)+cor; cor = (cor>0)? 1.035*cor+eps : 1.035*cor-eps; return (res==res+cor)? ((m)?res:-res) : csloww1(a,da,x); } break; case 0: case 2: if (a<0) {a=-a;da=-da;} u.x=big.x+a; y=a-(u.x-big.x)+da; xx=y*y; k=u.i[LOW_HALF]<<2; sn=sincos.x[k]; ssn=sincos.x[k+1]; cs=sincos.x[k+2]; ccs=sincos.x[k+3]; s = y + y*xx*(sn3 +xx*sn5); c = xx*(cs2 +xx*(cs4 + xx*cs6)); cor=(ccs-s*ssn-cs*c)-sn*s; res=cs+cor; cor=(cs-res)+cor; cor = (cor>0)? 1.025*cor+eps : 1.025*cor-eps; return (res==res+cor)? ((n)?-res:res) : csloww2(a,da,x,n); break; } } /* else if (k < 0x419921FB ) */ else if (k < 0x42F00000 ) { t = (x*hpinv.x + toint.x); xn = t - toint.x; v.x = t; xn1 = (xn+8.0e22)-8.0e22; xn2 = xn - xn1; y = ((((x - xn1*mp1.x) - xn1*mp2.x)-xn2*mp1.x)-xn2*mp2.x); n =v.i[LOW_HALF]&3; da = xn1*pp3.x; t=y-da; da = (y-t)-da; da = (da - xn2*pp3.x) -xn*pp4.x; a = t+da; da = (t-a)+da; eps = 1.0e-24; switch (n) { case 1: case 3: xx = a*a; if (n==1) {a=-a;da=-da;} if (xx < 0.01588) { t = (((((s5.x*xx + s4.x)*xx + s3.x)*xx + s2.x)*xx + s1.x)*a - 0.5*da)*xx+da; res = a+t; cor = (a-res)+t; cor = (cor>0)? 1.02*cor+eps : 1.02*cor -eps; return (res == res + cor)? res : bsloww(a,da,x,n); } else { if (a>0) {m=1;t=a;db=da;} else {m=0;t=-a;db=-da;} u.x=big.x+t; y=t-(u.x-big.x); xx=y*y; s = y + (db+y*xx*(sn3 +xx*sn5)); c = y*db+xx*(cs2 +xx*(cs4 + xx*cs6)); k=u.i[LOW_HALF]<<2; sn=sincos.x[k]; ssn=sincos.x[k+1]; cs=sincos.x[k+2]; ccs=sincos.x[k+3]; cor=(ssn+s*ccs-sn*c)+cs*s; res=sn+cor; cor=(sn-res)+cor; cor = (cor>0)? 1.035*cor+eps : 1.035*cor-eps; return (res==res+cor)? ((m)?res:-res) : bsloww1(a,da,x,n); } break; case 0: case 2: if (a<0) {a=-a;da=-da;} u.x=big.x+a; y=a-(u.x-big.x)+da; xx=y*y; k=u.i[LOW_HALF]<<2; sn=sincos.x[k]; ssn=sincos.x[k+1]; cs=sincos.x[k+2]; ccs=sincos.x[k+3]; s = y + y*xx*(sn3 +xx*sn5); c = xx*(cs2 +xx*(cs4 + xx*cs6)); cor=(ccs-s*ssn-cs*c)-sn*s; res=cs+cor; cor=(cs-res)+cor; cor = (cor>0)? 1.025*cor+eps : 1.025*cor-eps; return (res==res+cor)? ((n)?-res:res) : bsloww2(a,da,x,n); break; } } /* else if (k < 0x42F00000 ) */ else if (k < 0x7ff00000) {/* 281474976710656 <|x| <2^1024 */ n = __branred(x,&a,&da); switch (n) { case 1: if (a*a < 0.01588) return bsloww(-a,-da,x,n); else return bsloww1(-a,-da,x,n); break; case 3: if (a*a < 0.01588) return bsloww(a,da,x,n); else return bsloww1(a,da,x,n); break; case 0: case 2: return bsloww2(a,da,x,n); break; } } /* else if (k < 0x7ff00000 ) */ else return x / x; /* |x| > 2^1024 */ return 0; }