return y;
return x > y ? (x - y) : +0.f;
}
+
+INLINE_OVERLOADABLE float __gen_ocl_internal_pow(float x, float y) {
+ float z,ax,z_h,z_l,p_h,p_l;
+ float y1,t1,t2,r,s,sn,t,u,v,w;
+ int i,j,k,yisint,n;
+ int hx,hy,ix,iy,is;
+ float bp[2],dp_h[2],dp_l[2],
+ zero = 0.0,
+ one = 1.0,
+ two = 2.0,
+ two24 = 16777216.0, /* 0x4b800000 */
+ huge = 1.0e30,
+ tiny = 1.0e-30,
+ /* poly coefs for (3/2)*(log(x)-2s-2/3*s**3 */
+ L1 = 6.0000002384e-01, /* 0x3f19999a */
+ L2 = 4.2857143283e-01, /* 0x3edb6db7 */
+ L3 = 3.3333334327e-01, /* 0x3eaaaaab */
+ L4 = 2.7272811532e-01, /* 0x3e8ba305 */
+ L5 = 2.3066075146e-01, /* 0x3e6c3255 */
+ L6 = 2.0697501302e-01, /* 0x3e53f142 */
+ P1 = 1.6666667163e-01, /* 0x3e2aaaab */
+ P2 = -2.7777778450e-03, /* 0xbb360b61 */
+ P3 = 6.6137559770e-05, /* 0x388ab355 */
+ P4 = -1.6533901999e-06, /* 0xb5ddea0e */
+ P5 = 4.1381369442e-08, /* 0x3331bb4c */
+ lg2 = 6.9314718246e-01, /* 0x3f317218 */
+ lg2_h = 6.93145752e-01, /* 0x3f317200 */
+ lg2_l = 1.42860654e-06, /* 0x35bfbe8c */
+ ovt = 4.2995665694e-08, /* -(128-log2(ovfl+.5ulp)) */
+ cp = 9.6179670095e-01, /* 0x3f76384f =2/(3ln2) */
+ cp_h = 9.6179199219e-01, /* 0x3f763800 =head of cp */
+ cp_l = 4.7017383622e-06, /* 0x369dc3a0 =tail of cp_h */
+ ivln2 = 1.4426950216e+00, /* 0x3fb8aa3b =1/ln2 */
+ ivln2_h = 1.4426879883e+00, /* 0x3fb8aa00 =16b 1/ln2*/
+ ivln2_l = 7.0526075433e-06; /* 0x36eca570 =1/ln2 tail*/
+ bp[0] = 1.0,bp[1] = 1.5,
+ dp_h[0] = 0.0,dp_h[1] = 5.84960938e-01,
+ dp_l[0] = 0.0,dp_l[1] = 1.56322085e-06;
+ GEN_OCL_GET_FLOAT_WORD(hx,x);
+ GEN_OCL_GET_FLOAT_WORD(hy,y);
+ ix = hx&0x7fffffff; iy = hy&0x7fffffff;
+ if (ix < 0x00800000) { /* x < 2**-126 */
+ ix = 0;/* Gen does not support subnormal number now */
+ }
+ if (iy < 0x00800000) { /* y < 2**-126 */
+ iy = 0;/* Gen does not support subnormal number now */
+ }
+ /* y==zero: x**0 = 1 */
+ if(iy==0) return one;
+ if(hx==0x3f800000) return one;
+ /* +-NaN return x+y */
+ if(ix > 0x7f800000 || iy > 0x7f800000)
+ return (x+0.0f)+y+(0.0f);
+ /* determine if y is an odd int when x < 0
+ * yisint = 0 ... y is not an integer
+ * yisint = 1 ... y is an odd int
+ * yisint = 2 ... y is an even int
+ */
+ yisint = 0;
+ if(hx<0) {
+ if(iy>=0x4b800000) yisint = 2; /* even integer y */
+ else if(iy>=0x3f800000) {
+ k = (iy>>23)-0x7f; /* exponent */
+ j = iy>>(23-k);
+ if((j<<(23-k))==iy) yisint = 2-(j&1);
+ }
+ }
+ /* special value of y */
+ if (iy==0x7f800000) { /* y is +-inf */
+ if (ix==0x3f800000)
+ //return y - y; /* inf**+-1 is NaN */
+ return one;
+ else if (ix > 0x3f800000)/* (|x|>1)**+-inf = inf,0 */
+ return (hy>=0)? y: zero;
+ else /* (|x|<1)**-,+inf = inf,0 */
+ return (hy<0)?-y: zero;
+ }
+ if(iy==0x3f800000) { /* y is +-1 */
+ if(hy<0) return one/x; else return x;
+ }
+ if(hy==0x40000000) return x*x; /* y is 2 */
+ if(hy==0x3f000000) { /* y is 0.5 */
+ if(hx>=0)return __gen_ocl_sqrt(x);
+ }
+
+ ax = __gen_ocl_fabs(x);
+ /* special value of x */
+ if(ix==0x7f800000||ix==0||ix==0x3f800000){
+ z = ax; /*x is +-0,+-inf,+-1*/
+ if(hy<0) z = one/z; /* z = (1/|x|) */
+ if(hx<0) {
+ if(((ix-0x3f800000)|yisint)==0) {
+ z = (z-z)/(z-z); /* (-1)**non-int is NaN */
+ } else if(yisint==1)
+ z = -z; /* (x<0)**odd = -(|x|**odd) */
+ }
+ return z;
+ }
+ n = ((uint)hx>>31)-1;
+
+ /* (x<0)**(non-int) is NaN */
+ if((n|yisint)==0) return (x-x)/(x-x);
+
+ sn = one; /* s (sign of result -ve**odd) = -1 else = 1 */
+ if((n|(yisint-1))==0) sn = -one;/* (-ve)**(odd int) */
+
+ /* |y| is huge */
+ if(iy>0x4d000000) { /* if |y| > 2**27 */
+ /* over/underflow if x is not close to one */
+ if(ix<0x3f7ffff8) return (hy<0)? sn*huge*huge:sn*tiny*tiny;
+ if(ix>0x3f800007) return (hy>0)? sn*huge*huge:sn*tiny*tiny;
+ /* now |1-x| is tiny <= 2**-20, suffice to compute
+ log(x) by x-x^2/2+x^3/3-x^4/4 */
+ t = ax-1; /* t has 20 trailing zeros */
+ w = (t*t)*((float)0.5-t*(0.333333333333f-t*0.25f));
+ u = ivln2_h*t; /* ivln2_h has 16 sig. bits */
+ v = t*ivln2_l-w*ivln2;
+ t1 = u+v;
+ GEN_OCL_GET_FLOAT_WORD(is,t1);
+ GEN_OCL_SET_FLOAT_WORD(t1,is&0xfffff000);
+ t2 = v-(t1-u);
+ } else {
+ float s2,s_h,s_l,t_h,t_l;
+ n = 0;
+ /* take care subnormal number */
+ //if(ix<0x00800000)
+ //{ax *= two24; n -= 24; GEN_OCL_GET_FLOAT_WORD(ix,ax); }
+ n += ((ix)>>23)-0x7f;
+ j = ix&0x007fffff;
+ /* determine interval */
+ ix = j|0x3f800000; /* normalize ix */
+ if(j<=0x1cc471) k=0; /* |x|<sqrt(3/2) */
+ else if(j<0x5db3d7) k=1; /* |x|<sqrt(3) */
+ else {k=0;n+=1;ix -= 0x00800000;}
+ GEN_OCL_SET_FLOAT_WORD(ax,ix);
+
+ /* compute s = s_h+s_l = (x-1)/(x+1) or (x-1.5)/(x+1.5) */
+ u = ax-bp[k]; /* bp[0]=1.0, bp[1]=1.5 */
+ v = one/(ax+bp[k]);
+ s = u*v;
+ s_h = s;
+ GEN_OCL_GET_FLOAT_WORD(is,s_h);
+ GEN_OCL_SET_FLOAT_WORD(s_h,is&0xfffff000);
+ /* t_h=ax+bp[k] High */
+ is = ((ix>>1)&0xfffff000)|0x20000000;
+ GEN_OCL_SET_FLOAT_WORD(t_h,is+0x00400000+(k<<21));
+ t_l = ax - (t_h-bp[k]);
+ s_l = v*((u-s_h*t_h)-s_h*t_l);
+ /* compute log(ax) */
+ s2 = s*s;
+ r = s2*s2*(L1+s2*(L2+s2*(L3+s2*(L4+s2*(L5+s2*L6)))));
+ r += s_l*(s_h+s);
+ s2 = s_h*s_h;
+ t_h = 3.0f+s2+r;
+ GEN_OCL_GET_FLOAT_WORD(is,t_h);
+ GEN_OCL_SET_FLOAT_WORD(t_h,is&0xfffff000);
+ t_l = r-((t_h-3.0f)-s2);
+ /* u+v = s*(1+...) */
+ u = s_h*t_h;
+ v = s_l*t_h+t_l*s;
+ /* 2/(3log2)*(s+...) */
+ p_h = u+v;
+ GEN_OCL_GET_FLOAT_WORD(is,p_h);
+ GEN_OCL_SET_FLOAT_WORD(p_h,is&0xfffff000);
+ p_l = v-(p_h-u);
+ z_h = cp_h*p_h; /* cp_h+cp_l = 2/(3*log2) */
+ z_l = cp_l*p_h+p_l*cp+dp_l[k];
+ /* log2(ax) = (s+..)*2/(3*log2) = n + dp_h + z_h + z_l */
+ t = (float)n;
+ t1 = (((z_h+z_l)+dp_h[k])+t);
+ GEN_OCL_GET_FLOAT_WORD(is,t1);
+ GEN_OCL_SET_FLOAT_WORD(t1,is&0xfffff000);
+ t2 = z_l-(((t1-t)-dp_h[k])-z_h);
+ }
+
+ /* split up y into y1+y2 and compute (y1+y2)*(t1+t2) */
+ GEN_OCL_GET_FLOAT_WORD(is,y);
+ GEN_OCL_SET_FLOAT_WORD(y1,is&0xfffff000);
+ p_l = (y-y1)*t1+y*t2;
+ p_h = y1*t1;
+ z = p_l+p_h;
+ GEN_OCL_GET_FLOAT_WORD(j,z);
+ if (j>0x43000000) /* if z > 128 */
+ return sn*huge*huge; /* overflow */
+ else if (j==0x43000000) { /* if z == 128 */
+ if(p_l+ovt>z-p_h) return sn*huge*huge; /* overflow */
+ }
+ else if ((j&0x7fffffff)>0x43160000) /* z <= -150 */
+ return sn*tiny*tiny; /* underflow */
+ else if (j==0xc3160000){ /* z == -150 */
+ if(p_l<=z-p_h) return sn*tiny*tiny; /* underflow */
+ }
+
+ /*
+ * compute 2**(p_h+p_l)
+ */
+ i = j&0x7fffffff;
+ k = (i>>23)-0x7f;
+ n = 0;
+ if(i>0x3f000000) { /* if |z| > 0.5, set n = [z+0.5] */
+ n = j+(0x00800000>>(k+1));
+ k = ((n&0x7fffffff)>>23)-0x7f; /* new k for n */
+ GEN_OCL_SET_FLOAT_WORD(t,n&~(0x007fffff>>k));
+ n = ((n&0x007fffff)|0x00800000)>>(23-k);
+ if(j<0) n = -n;
+ p_h -= t;
+ }
+ t = p_l+p_h;
+ GEN_OCL_GET_FLOAT_WORD(is,t);
+ GEN_OCL_SET_FLOAT_WORD(t,is&0xffff8000);
+ u = t*lg2_h;
+ v = (p_l-(t-p_h))*lg2+t*lg2_l;
+ z = u+v;
+ w = v-(z-u);
+ t = z*z;
+ t1 = z - t*(P1+t*(P2+t*(P3+t*(P4+t*P5))));
+ r = (z*t1)/(t1-two)-(w+z*w);
+ z = one-(r-z);
+ GEN_OCL_GET_FLOAT_WORD(j,z);
+ j += (n<<23);
+ if((j>>23)<=0) z = __gen_ocl_scalbnf(z,n); /* subnormal output */
+ else GEN_OCL_SET_FLOAT_WORD(z,j);
+ return sn*z;
+}
+
+
INLINE_OVERLOADABLE float hypot(float x, float y) {
//return __gen_ocl_sqrt(x*x + y*y);
float a,b,an,bn,cn;
return powr(x, n);
}
INLINE_OVERLOADABLE float rootn(float x, int n) {
- return powr(x, 1.f / n);
+ float ax,re;
+ int sign = 0;
+ if( n == 0 )return NAN;
+ //rootn ( x, n ) returns a NaN for x < 0 and n is even.
+ if( x < 0 && 0 == (n&1) )
+ return NAN;
+ if( x == 0.0 ){
+ switch( n & 0x80000001 ){
+ //rootn ( +-0, n ) is +0 for even n > 0.
+ case 0:
+ return 0.0f;
+ //rootn ( +-0, n ) is +-0 for odd n > 0.
+ case 1:
+ return x;
+ //rootn ( +-0, n ) is +inf for even n < 0.
+ case 0x80000000:
+ return INFINITY;
+
+ //rootn ( +-0, n ) is +-inf for odd n < 0.
+ case 0x80000001:
+ return __gen_ocl_internal_copysign(INFINITY, x);
+ }
+ }
+ ax = __gen_ocl_fabs(x);
+ if(x <0.0f && (n&1))
+ sign = 1;
+ re = __gen_ocl_internal_pow(ax,1.f/n);
+ if(sign)
+ re = -re;
+ return re;
}
/////////////////////////////////////////////////////////////////////////////
projects / contrib / beignet.git / commitdiff