else if (k>0x7ff00000 || (k == 0x7ff00000 && u.i[LOW_HALF] != 0)) return x;
double __ieee754_acos(double x){  double x1,x2,xx,s1,s2,res1,p,t,res,r,cor,cc,y,c,z,w[2],eps;#if 0  double fc;#endif  mynumber u,v;  int4 k,m,n;#if 0  int4 nn;#endif  u.x = x;  m = u.i[HIGH_HALF];  k = 0x7fffffff&m;  /*-------------------  |x|<2.77556*10^-17 ----------------------*/  if (k < 0x3c880000) return hp0.x;  /*-----------------  2.77556*10^-17 <= |x| < 2^-3 --------------*/  else  if (k < 0x3fc00000) {    x2 = x*x;    t = (((((f6*x2 + f5)*x2 + f4)*x2 + f3)*x2 + f2)*x2 + f1)*(x2*x);    r=hp0.x-x;    cor=(((hp0.x-r)-x)+hp1.x)-t;    res = r+cor;    cor = (r-res)+cor;    if (res == res+1.004*cor) return res;    else {      x1 = x+big;      xx = x*x;      x1 -= big;      x2 = x - x1;      p = x1*x1*x1;      s1 = a1.x*p;      s2 = ((((((c7*xx + c6)*xx + c5)*xx + c4)*xx + c3)*xx + c2)*xx*xx*x +	    ((a1.x+a2.x)*x2*x2+ 0.5*x1*x)*x2) + a2.x*p;      res1 = x+s1;      s2 = ((x-res1)+s1)+s2;      r=hp0.x-res1;      cor=(((hp0.x-r)-res1)+hp1.x)-s2;      res = r+cor;      cor = (r-res)+cor;      if (res == res+1.00004*cor) return res;      else {	__doasin(x,0,w);	r=hp0.x-w[0];	cor=((hp0.x-r)-w[0])+(hp1.x-w[1]);	res=r+cor;	cor=(r-res)+cor;	if (res ==(res +1.00000001*cor)) return res;	else {	  res1=res+1.1*cor;	  return __cos32(x,res,res1);	}      }    }  }    /*   else  if (k < 0x3fc00000)    */  /*----------------------  0.125 <= |x| < 0.5 --------------------*/  else  if (k < 0x3fe00000) {    if (k<0x3fd00000) n = 11*((k&0x000fffff)>>15);    else n = 11*((k&0x000fffff)>>14)+352;    if (m>0) xx = x - asncs.x[n];    else xx = -x - asncs.x[n];    t = asncs.x[n+1]*xx;    p=xx*xx*(asncs.x[n+2]+xx*(asncs.x[n+3]+xx*(asncs.x[n+4]+                   xx*(asncs.x[n+5]+xx*asncs.x[n+6]))))+asncs.x[n+7];    t+=p;    y = (m>0)?(hp0.x-asncs.x[n+8]):(hp0.x+asncs.x[n+8]);    t = (m>0)?(hp1.x-t):(hp1.x+t);    res = y+t;    if (res == res+1.02*((y-res)+t)) return res;    else {      r=asncs.x[n+8]+xx*asncs.x[n+9];      t=((asncs.x[n+8]-r)+xx*asncs.x[n+9])+(p+xx*asncs.x[n+10]);      if (m>0)	{p = hp0.x-r; t = (((hp0.x-p)-r)-t)+hp1.x; }      else	{p = hp0.x+r; t = ((hp0.x-p)+r)+(hp1.x+t); }      res = p+t;      cor = (p-res)+t;      if (res == (res+1.0002*cor)) return res;      else {	res1=res+1.1*cor;	z=0.5*(res1-res);	__docos(res,z,w);	z=(w[0]-x)+w[1];	if (z>1.0e-27) return max(res,res1);	else if (z<-1.0e-27) return min(res,res1);	else return __cos32(x,res,res1);      }    }  }    /*   else  if (k < 0x3fe00000)    */  /*--------------------------- 0.5 <= |x| < 0.75 ---------------------*/  else  if (k < 0x3fe80000) {    n = 1056+((k&0x000fe000)>>11)*3;    if (m>0) {xx = x - asncs.x[n]; eps=1.04; }    else {xx = -x - asncs.x[n]; eps=1.02; }    t = asncs.x[n+1]*xx;    p=xx*xx*(asncs.x[n+2]+xx*(asncs.x[n+3]+xx*(asncs.x[n+4]+                   xx*(asncs.x[n+5]+xx*(asncs.x[n+6]+                   xx*asncs.x[n+7])))))+asncs.x[n+8];    t+=p;   y = (m>0)?(hp0.x-asncs.x[n+9]):(hp0.x+asncs.x[n+9]);   t = (m>0)?(hp1.x-t):(hp1.x+t);   res = y+t;   if (res == res+eps*((y-res)+t)) return res;   else {     r=asncs.x[n+9]+xx*asncs.x[n+10];     t=((asncs.x[n+9]-r)+xx*asncs.x[n+10])+(p+xx*asncs.x[n+11]);     if (m>0) {p = hp0.x-r; t = (((hp0.x-p)-r)-t)+hp1.x; eps=1.0004; }     else   {p = hp0.x+r; t = ((hp0.x-p)+r)+(hp1.x+t); eps=1.0002; }     res = p+t;     cor = (p-res)+t;     if (res == (res+eps*cor)) return res;     else {       res1=res+1.1*cor;       z=0.5*(res1-res);       __docos(res,z,w);       z=(w[0]-x)+w[1];       if (z>1.0e-27) return max(res,res1);       else if (z<-1.0e-27) return min(res,res1);       else return __cos32(x,res,res1);     }   }  }    /*   else  if (k < 0x3fe80000)    *//*------------------------- 0.75 <= |x| < 0.921875 -------------*/  else  if (k < 0x3fed8000) {    n = 992+((k&0x000fe000)>>13)*13;    if (m>0) {xx = x - asncs.x[n]; eps = 1.04; }    else {xx = -x - asncs.x[n]; eps = 1.01; }    t = asncs.x[n+1]*xx;    p=xx*xx*(asncs.x[n+2]+xx*(asncs.x[n+3]+xx*(asncs.x[n+4]+                      xx*(asncs.x[n+5]+xx*(asncs.x[n+6]+xx*(asncs.x[n+7]+                      xx*asncs.x[n+8]))))))+asncs.x[n+9];    t+=p;    y = (m>0)?(hp0.x-asncs.x[n+10]):(hp0.x+asncs.x[n+10]);    t = (m>0)?(hp1.x-t):(hp1.x+t);    res = y+t;    if (res == res+eps*((y-res)+t)) return res;    else {      r=asncs.x[n+10]+xx*asncs.x[n+11];      t=((asncs.x[n+10]-r)+xx*asncs.x[n+11])+(p+xx*asncs.x[n+12]);      if (m>0) {p = hp0.x-r; t = (((hp0.x-p)-r)-t)+hp1.x; eps=1.0032; }      else   {p = hp0.x+r; t = ((hp0.x-p)+r)+(hp1.x+t); eps=1.0008; }      res = p+t;      cor = (p-res)+t;      if (res == (res+eps*cor)) return res;      else {	res1=res+1.1*cor;	z=0.5*(res1-res);	__docos(res,z,w);	z=(w[0]-x)+w[1];	if (z>1.0e-27) return max(res,res1);	else if (z<-1.0e-27) return min(res,res1);	else return __cos32(x,res,res1);      }    }  }    /*   else  if (k < 0x3fed8000)    *//*-------------------0.921875 <= |x| < 0.953125 ------------------*/  else  if (k < 0x3fee8000) {    n = 884+((k&0x000fe000)>>13)*14;    if (m>0) {xx = x - asncs.x[n]; eps=1.04; }    else {xx = -x - asncs.x[n]; eps =1.005; }    t = asncs.x[n+1]*xx;    p=xx*xx*(asncs.x[n+2]+xx*(asncs.x[n+3]+xx*(asncs.x[n+4]+                   xx*(asncs.x[n+5]+xx*(asncs.x[n+6]		   +xx*(asncs.x[n+7]+xx*(asncs.x[n+8]+                   xx*asncs.x[n+9])))))))+asncs.x[n+10];    t+=p;    y = (m>0)?(hp0.x-asncs.x[n+11]):(hp0.x+asncs.x[n+11]);    t = (m>0)?(hp1.x-t):(hp1.x+t);    res = y+t;    if (res == res+eps*((y-res)+t)) return res;    else {      r=asncs.x[n+11]+xx*asncs.x[n+12];      t=((asncs.x[n+11]-r)+xx*asncs.x[n+12])+(p+xx*asncs.x[n+13]);      if (m>0) {p = hp0.x-r; t = (((hp0.x-p)-r)-t)+hp1.x; eps=1.0030; }      else   {p = hp0.x+r; t = ((hp0.x-p)+r)+(hp1.x+t); eps=1.0005; }      res = p+t;      cor = (p-res)+t;      if (res == (res+eps*cor)) return res;      else {	res1=res+1.1*cor;	z=0.5*(res1-res);	__docos(res,z,w);	z=(w[0]-x)+w[1];	if (z>1.0e-27) return max(res,res1);	else if (z<-1.0e-27) return min(res,res1);	else return __cos32(x,res,res1);      }    }  }    /*   else  if (k < 0x3fee8000)    */  /*--------------------0.953125 <= |x| < 0.96875 ----------------*/  else  if (k < 0x3fef0000) {    n = 768+((k&0x000fe000)>>13)*15;    if (m>0) {xx = x - asncs.x[n]; eps=1.04; }    else {xx = -x - asncs.x[n]; eps=1.005;}    t = asncs.x[n+1]*xx;    p=xx*xx*(asncs.x[n+2]+xx*(asncs.x[n+3]+xx*(asncs.x[n+4]+            xx*(asncs.x[n+5]+xx*(asncs.x[n+6]	    +xx*(asncs.x[n+7]+xx*(asncs.x[n+8]+xx*(asncs.x[n+9]+            xx*asncs.x[n+10]))))))))+asncs.x[n+11];    t+=p;    y = (m>0)?(hp0.x-asncs.x[n+12]):(hp0.x+asncs.x[n+12]);   t = (m>0)?(hp1.x-t):(hp1.x+t);   res = y+t;   if (res == res+eps*((y-res)+t)) return res;   else {     r=asncs.x[n+12]+xx*asncs.x[n+13];     t=((asncs.x[n+12]-r)+xx*asncs.x[n+13])+(p+xx*asncs.x[n+14]);     if (m>0) {p = hp0.x-r; t = (((hp0.x-p)-r)-t)+hp1.x; eps=1.0030; }     else   {p = hp0.x+r; t = ((hp0.x-p)+r)+(hp1.x+t); eps=1.0005; }     res = p+t;     cor = (p-res)+t;     if (res == (res+eps*cor)) return res;     else {       res1=res+1.1*cor;       z=0.5*(res1-res);       __docos(res,z,w);       z=(w[0]-x)+w[1];       if (z>1.0e-27) return max(res,res1);       else if (z<-1.0e-27) return min(res,res1);       else return __cos32(x,res,res1);     }   }  }    /*   else  if (k < 0x3fef0000)    */  /*-----------------0.96875 <= |x| < 1 ---------------------------*/  else  if (k<0x3ff00000)  {    z = 0.5*((m>0)?(1.0-x):(1.0+x));    v.x=z;    k=v.i[HIGH_HALF];    t=inroot[(k&0x001fffff)>>14]*powtwo[511-(k>>21)];    r=1.0-t*t*z;    t = t*(rt0+r*(rt1+r*(rt2+r*rt3)));    c=t*z;    t=c*(1.5-0.5*t*c);    y = (t27*c+c)-t27*c;    cc = (z-y*y)/(t+y);    p=(((((f6*z+f5)*z+f4)*z+f3)*z+f2)*z+f1)*z;    if (m<0) {      cor = (hp1.x - cc)-(y+cc)*p;      res1 = hp0.x - y;      res =res1 + cor;      if (res == res+1.002*((res1-res)+cor)) return (res+res);      else {	c=y+cc;	cc=(y-c)+cc;	__doasin(c,cc,w);	res1=hp0.x-w[0];	cor=((hp0.x-res1)-w[0])+(hp1.x-w[1]);	res = res1+cor;	cor = (res1-res)+cor;	if (res==(res+1.000001*cor)) return (res+res);	else {	  res=res+res;	  res1=res+1.2*cor;	  return __cos32(x,res,res1);	}      }    }    else {      cor = cc+p*(y+cc);      res = y + cor;      if (res == res+1.03*((y-res)+cor)) return (res+res);      else {	c=y+cc;	cc=(y-c)+cc;	__doasin(c,cc,w);	res = w[0];	cor=w[1];	if (res==(res+1.000001*cor)) return (res+res);	else {	  res=res+res;	  res1=res+1.2*cor;	  return __cos32(x,res,res1);	}      }    }  }    /*   else  if (k < 0x3ff00000)    */  /*---------------------------- |x|>=1 -----------------------*/  else  if (k==0x3ff00000 && u.i[LOW_HALF]==0) return (m>0)?0:2.0*hp0.x;  else {    u.i[HIGH_HALF]=0x7ff00000;    v.i[HIGH_HALF]=0x7ff00000;    u.i[LOW_HALF]=0;    v.i[LOW_HALF]=0;    return u.x/v.x;  }}