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+/* e_fmodf.c -- float version of e_fmod.c.
+ * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
+ */
+
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/*
+ * fmodf(x,y)
+ * Return x mod y in exact arithmetic
+ * Method: shift and subtract
+ */
+
+#include <math.h>
+#include "math_private.h"
+
+static const float one = 1.0, Zero[] = {0.0, -0.0,};
+
+float
+fmodf(float x, float y)
+{
+ int32_t n,hx,hy,hz,ix,iy,sx,i;
+
+ GET_FLOAT_WORD(hx,x);
+ GET_FLOAT_WORD(hy,y);
+ sx = hx&0x80000000; /* sign of x */
+ hx ^=sx; /* |x| */
+ hy &= 0x7fffffff; /* |y| */
+
+ /* purge off exception values */
+ if(hy==0||(hx>=0x7f800000)|| /* y=0,or x not finite */
+ (hy>0x7f800000)) /* or y is NaN */
+ return (x*y)/(x*y);
+ if(hx<hy) return x; /* |x|<|y| return x */
+ if(hx==hy)
+ return Zero[(uint32_t)sx>>31]; /* |x|=|y| return x*0*/
+
+ /* determine ix = ilogb(x) */
+ if(hx<0x00800000) { /* subnormal x */
+ for (ix = -126,i=(hx<<8); i>0; i<<=1) ix -=1;
+ } else ix = (hx>>23)-127;
+
+ /* determine iy = ilogb(y) */
+ if(hy<0x00800000) { /* subnormal y */
+ for (iy = -126,i=(hy<<8); i>=0; i<<=1) iy -=1;
+ } else iy = (hy>>23)-127;
+
+ /* set up {hx,lx}, {hy,ly} and align y to x */
+ if(ix >= -126)
+ hx = 0x00800000|(0x007fffff&hx);
+ else { /* subnormal x, shift x to normal */
+ n = -126-ix;
+ hx = hx<<n;
+ }
+ if(iy >= -126)
+ hy = 0x00800000|(0x007fffff&hy);
+ else { /* subnormal y, shift y to normal */
+ n = -126-iy;
+ hy = hy<<n;
+ }
+
+ /* fix point fmod */
+ n = ix - iy;
+ while(n--) {
+ hz=hx-hy;
+ if(hz<0){hx = hx+hx;}
+ else {
+ if(hz==0) /* return sign(x)*0 */
+ return Zero[(uint32_t)sx>>31];
+ hx = hz+hz;
+ }
+ }
+ hz=hx-hy;
+ if(hz>=0) {hx=hz;}
+
+ /* convert back to floating value and restore the sign */
+ if(hx==0) /* return sign(x)*0 */
+ return Zero[(uint32_t)sx>>31];
+ while(hx<0x00800000) { /* normalize x */
+ hx = hx+hx;
+ iy -= 1;
+ }
+ if(iy>= -126) { /* normalize output */
+ hx = ((hx-0x00800000)|((iy+127)<<23));
+ SET_FLOAT_WORD(x,hx|sx);
+ } else { /* subnormal output */
+ n = -126 - iy;
+ hx >>= n;
+ SET_FLOAT_WORD(x,hx|sx);
+ x *= one; /* create necessary signal */
+ }
+ return x; /* exact output */
+}