getaddrinfo: add EAI_NODATA error code to distinguish NODATA vs NxDomain

[musl] / src / math / atan2l.c

diff --git a/src/math/atan2l.c b/src/math/atan2l.c
index e86dbff..f0937a9 100644 (file)
--- a/src/math/atan2l.c
+++ b/src/math/atan2l.c
@@ -27,68 +27,52 @@ long double atan2l(long double y, long double x)
 
 long double atan2l(long double y, long double x)
 {
-       union IEEEl2bits ux, uy;
+       union ldshape ux, uy;
        long double z;
-       int32_t k,m;
-       int16_t exptx, expsignx, expty, expsigny;
+       int m, ex, ey;
 
-       uy.e = y;
-       expsigny = uy.xbits.expsign;
-       expty = expsigny & 0x7fff;
-       ux.e = x;
-       expsignx = ux.xbits.expsign;
-       exptx = expsignx & 0x7fff;
-       if ((exptx==0x7fff &&
-            ((ux.bits.manh&~LDBL_NBIT)|ux.bits.manl)!=0) || /* x is NaN */
-           (expty==0x7fff &&
-            ((uy.bits.manh&~LDBL_NBIT)|uy.bits.manl)!=0))   /* y is NaN */
+       if (isnan(x) || isnan(y))
                return x+y;
-       if (expsignx==0x3fff && ((ux.bits.manh&~LDBL_NBIT)|ux.bits.manl)==0) /* x=1.0 */
+       if (x == 1)
                return atanl(y);
-       m = ((expsigny>>15)&1) | ((expsignx>>14)&2);  /* 2*sign(x)+sign(y) */
-
-       /* when y = 0 */
-       if (expty==0 && ((uy.bits.manh&~LDBL_NBIT)|uy.bits.manl)==0) {
+       ux.f = x;
+       uy.f = y;
+       ex = ux.i.se & 0x7fff;
+       ey = uy.i.se & 0x7fff;
+       m = 2*(ux.i.se>>15) | uy.i.se>>15;
+       if (y == 0) {
                switch(m) {
                case 0:
                case 1: return y;           /* atan(+-0,+anything)=+-0 */
-               case 2: return  2*pio2_hi+0x1p-1000; /* atan(+0,-anything) = pi */
-               case 3: return -2*pio2_hi-0x1p-1000; /* atan(-0,-anything) =-pi */
+               case 2: return  2*pio2_hi;  /* atan(+0,-anything) = pi */
+               case 3: return -2*pio2_hi;  /* atan(-0,-anything) =-pi */
                }
        }
-       /* when x = 0 */
-       if (exptx==0 && ((ux.bits.manh&~LDBL_NBIT)|ux.bits.manl)==0)
-               return expsigny < 0 ? -pio2_hi-0x1p-1000 : pio2_hi+0x1p-1000;
-       /* when x is INF */
-       if (exptx == 0x7fff) {
-               if (expty == 0x7fff) {
+       if (x == 0)
+               return m&1 ? -pio2_hi : pio2_hi;
+       if (ex == 0x7fff) {
+               if (ey == 0x7fff) {
                        switch(m) {
-                       case 0: return  pio2_hi*0.5+0x1p-1000; /* atan(+INF,+INF) */
-                       case 1: return -pio2_hi*0.5-0x1p-1000; /* atan(-INF,+INF) */
-                       case 2: return  1.5*pio2_hi+0x1p-1000; /* atan(+INF,-INF) */
-                       case 3: return -1.5*pio2_hi-0x1p-1000; /* atan(-INF,-INF) */
+                       case 0: return  pio2_hi/2;   /* atan(+INF,+INF) */
+                       case 1: return -pio2_hi/2;   /* atan(-INF,+INF) */
+                       case 2: return  1.5*pio2_hi; /* atan(+INF,-INF) */
+                       case 3: return -1.5*pio2_hi; /* atan(-INF,-INF) */
                        }
                } else {
                        switch(m) {
                        case 0: return  0.0;        /* atan(+...,+INF) */
                        case 1: return -0.0;        /* atan(-...,+INF) */
-                       case 2: return  2*pio2_hi+0x1p-1000; /* atan(+...,-INF) */
-                       case 3: return -2*pio2_hi-0x1p-1000; /* atan(-...,-INF) */
+                       case 2: return  2*pio2_hi;  /* atan(+...,-INF) */
+                       case 3: return -2*pio2_hi;  /* atan(-...,-INF) */
                        }
                }
        }
-       /* when y is INF */
-       if (expty == 0x7fff)
-               return expsigny < 0 ? -pio2_hi-0x1p-1000 : pio2_hi+0x1p-1000;
-
-       /* compute y/x */
-       k = expty-exptx;
-       if(k > LDBL_MANT_DIG+2) { /* |y/x| huge */
-               z = pio2_hi+0x1p-1000;
-               m &= 1;
-       } else if (expsignx < 0 && k < -LDBL_MANT_DIG-2) /* |y/x| tiny, x<0 */
+       if (ex+120 < ey || ey == 0x7fff)
+               return m&1 ? -pio2_hi : pio2_hi;
+       /* z = atan(|y/x|) without spurious underflow */
+       if ((m&2) && ey+120 < ex)  /* |y/x| < 0x1p-120, x<0 */
                z = 0.0;
-       else                     /* safe to do y/x */
+       else
                z = atanl(fabsl(y/x));
        switch (m) {
        case 0: return z;               /* atan(+,+) */