 @@ -1,123 +1,123 @@
 /* @(#)e_atan2.c 5.1 93/09/24 */
 /*
  * ====================================================
  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
  * Developed at SunPro, a Sun Microsystems, Inc. business.
  * Permission to use, copy, modify, and distribute this
  * software is freely granted, provided that this notice
  * is preserved.
  * ====================================================
  */
 #include <sys/cdefs.h>
 #if defined(LIBM_SCCS) && !defined(lint)
-__RCSID("$NetBSD: e_atan2.c,v 1.12 2002/05/26 22:01:48 wiz Exp $");
+__RCSID("$NetBSD: e_atan2.c,v 1.13 2018/03/10 09:44:47 eadler Exp $");
 #endif
 /* __ieee754_atan2(y,x)
  * Method :
  *	1. Reduce y to positive by atan2(y,x)=-atan2(-y,x).
  *	2. Reduce x to positive by (if x and y are unexceptional):
  *		ARG (x+iy) = arctan(y/x)   	   ... if x > 0,
  *		ARG (x+iy) = pi - arctan[y/(-x)]   ... if x < 0,
+ *
  * Special cases:
+ *
  *	ATAN2((anything), NaN ) is NaN;
  *	ATAN2(NAN , (anything) ) is NaN;
  *	ATAN2(+-0, +(anything but NaN)) is +-0  ;
  *	ATAN2(+-0, -(anything but NaN)) is +-pi ;
  *	ATAN2(+-(anything but 0 and NaN), 0) is +-pi/2;
  *	ATAN2(+-(anything but INF and NaN), +INF) is +-0 ;
  *	ATAN2(+-(anything but INF and NaN), -INF) is +-pi;
  *	ATAN2(+-INF,+INF ) is +-pi/4 ;
  *	ATAN2(+-INF,-INF ) is +-3pi/4;
  *	ATAN2(+-INF, (anything but,0,NaN, and INF)) is +-pi/2;
+ *
  * Constants:
  * The hexadecimal values are the intended ones for the following
  * constants. The decimal values may be used, provided that the
  * compiler will convert from decimal to binary accurately enough
  * to produce the hexadecimal values shown.
  */
 #include "math.h"
 #include "math_private.h"
 static const double
 tiny  = 1.0e-300,
 zero  = 0.0,
 pi_o_4  = 7.8539816339744827900E-01, /* 0x3FE921FB, 0x54442D18 */
 pi_o_2  = 1.5707963267948965580E+00, /* 0x3FF921FB, 0x54442D18 */
 pi      = 3.1415926535897931160E+00, /* 0x400921FB, 0x54442D18 */
 pi_lo   = 1.2246467991473531772E-16; /* 0x3CA1A626, 0x33145C07 */
 double
 __ieee754_atan2(double y, double x)
+{
 	double z;
 	int32_t k,m,hx,hy,ix,iy;
 	u_int32_t lx,ly;
 	EXTRACT_WORDS(hx,lx,x);
 	ix = hx&0x7fffffff;
 	EXTRACT_WORDS(hy,ly,y);
 	iy = hy&0x7fffffff;
 	if(((ix|((lx|-lx)>>31))>0x7ff00000)||
 	   ((iy|((ly|-ly)>>31))>0x7ff00000))	/* x or y is NaN */
 	   return x+y;
-	if(((hx-0x3ff00000)|lx)==0) return atan(y);   /* x=1.0 */
+	if(hx==0x3ff00000&&lx==0) return atan(y);   /* x=1.0 */
 	m = ((hy>>31)&1)|((hx>>30)&2);	/* 2*sign(x)+sign(y) */
     /* when y = 0 */
 	if((iy|ly)==0) {
 	    switch(m) {
 		case 0:
 		case 1: return y; 	/* atan(+-0,+anything)=+-0 */
 		case 2: return  pi+tiny;/* atan(+0,-anything) = pi */
 		case 3: return -pi-tiny;/* atan(-0,-anything) =-pi */
+	    }
+	}
     /* when x = 0 */
 	if((ix|lx)==0) return (hy<0)?  -pi_o_2-tiny: pi_o_2+tiny;
     /* when x is INF */
 	if(ix==0x7ff00000) {
 	    if(iy==0x7ff00000) {
 		switch(m) {
 		    case 0: return  pi_o_4+tiny;/* atan(+INF,+INF) */
 		    case 1: return -pi_o_4-tiny;/* atan(-INF,+INF) */
 		    case 2: return  3.0*pi_o_4+tiny;/*atan(+INF,-INF)*/
 		    case 3: return -3.0*pi_o_4-tiny;/*atan(-INF,-INF)*/
+		}
 	    } else {
 		switch(m) {
 		    case 0: return  zero  ;	/* atan(+...,+INF) */
 		    case 1: return -zero  ;	/* atan(-...,+INF) */
 		    case 2: return  pi+tiny  ;	/* atan(+...,-INF) */
 		    case 3: return -pi-tiny  ;	/* atan(-...,-INF) */
+		}
+	    }
+	}
     /* when y is INF */
 	if(iy==0x7ff00000) return (hy<0)? -pi_o_2-tiny: pi_o_2+tiny;
     /* compute y/x */
 	k = (iy-ix)>>20;
 	if(k > 60) z=pi_o_2+0.5*pi_lo; 	/* |y/x| >  2**60 */
 	else if(hx<0&&k<-60) z=0.0; 	/* |y|/x < -2**60 */
 	else z=atan(fabs(y/x));		/* safe to do y/x */
 	switch (m) {
 	    case 0: return       z  ;	/* atan(+,+) */
 	    case 1: {
 	    	      u_int32_t zh;
 		      GET_HIGH_WORD(zh,z);
 		      SET_HIGH_WORD(z,zh ^ 0x80000000);
+		    }
 		    return       z  ;	/* atan(-,+) */
 	    case 2: return  pi-(z-pi_lo);/* atan(+,-) */
 	    default: /* case 3 */
 	    	    return  (z-pi_lo)-pi;/* atan(-,-) */
+	}
+}