Added SDL_fmod() and SDL_fmodf()

src/libm/e_fmod.c

@@ -0,0 +1,144 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/*
+ * __ieee754_fmod(x,y)
+ * Return x mod y in exact arithmetic
+ * Method: shift and subtract
+ */
+
+#include "math_libm.h"
+#include "math_private.h"
+
+static const double one = 1.0, Zero[] = {0.0, -0.0,};
+
+double attribute_hidden __ieee754_fmod(double x, double y)
+{
+	int32_t n,hx,hy,hz,ix,iy,sx,i;
+	u_int32_t lx,ly,lz;
+
+	EXTRACT_WORDS(hx,lx,x);
+	EXTRACT_WORDS(hy,ly,y);
+	sx = hx&0x80000000;		/* sign of x */
+	hx ^=sx;		/* |x| */
+	hy &= 0x7fffffff;	/* |y| */
+
+    /* purge off exception values */
+	if((hy|ly)==0||(hx>=0x7ff00000)||	/* y=0,or x not finite */
+	  ((hy|((ly|-ly)>>31))>0x7ff00000))	/* or y is NaN */
+	    return (x*y)/(x*y);
+	if(hx<=hy) {
+	    if((hx<hy)||(lx<ly)) return x;	/* |x|<|y| return x */
+	    if(lx==ly)
+		return Zero[(u_int32_t)sx>>31];	/* |x|=|y| return x*0*/
+	}
+
+    /* determine ix = ilogb(x) */
+	if(hx<0x00100000) {	/* subnormal x */
+	    if(hx==0) {
+		for (ix = -1043, i=lx; i>0; i<<=1) ix -=1;
+	    } else {
+		for (ix = -1022,i=(hx<<11); i>0; i<<=1) ix -=1;
+	    }
+	} else ix = (hx>>20)-1023;
+
+    /* determine iy = ilogb(y) */
+	if(hy<0x00100000) {	/* subnormal y */
+	    if(hy==0) {
+		for (iy = -1043, i=ly; i>0; i<<=1) iy -=1;
+	    } else {
+		for (iy = -1022,i=(hy<<11); i>0; i<<=1) iy -=1;
+	    }
+	} else iy = (hy>>20)-1023;
+
+    /* set up {hx,lx}, {hy,ly} and align y to x */
+	if(ix >= -1022)
+	    hx = 0x00100000|(0x000fffff&hx);
+	else {		/* subnormal x, shift x to normal */
+	    n = -1022-ix;
+	    if(n<=31) {
+	        hx = (hx<<n)|(lx>>(32-n));
+	        lx <<= n;
+	    } else {
+		hx = lx<<(n-32);
+		lx = 0;
+	    }
+	}
+	if(iy >= -1022)
+	    hy = 0x00100000|(0x000fffff&hy);
+	else {		/* subnormal y, shift y to normal */
+	    n = -1022-iy;
+	    if(n<=31) {
+	        hy = (hy<<n)|(ly>>(32-n));
+	        ly <<= n;
+	    } else {
+		hy = ly<<(n-32);
+		ly = 0;
+	    }
+	}
+
+    /* fix point fmod */
+	n = ix - iy;
+	while(n--) {
+	    hz=hx-hy;lz=lx-ly; if(lx<ly) hz -= 1;
+	    if(hz<0){hx = hx+hx+(lx>>31); lx = lx+lx;}
+	    else {
+	    	if((hz|lz)==0) 		/* return sign(x)*0 */
+		    return Zero[(u_int32_t)sx>>31];
+	    	hx = hz+hz+(lz>>31); lx = lz+lz;
+	    }
+	}
+	hz=hx-hy;lz=lx-ly; if(lx<ly) hz -= 1;
+	if(hz>=0) {hx=hz;lx=lz;}
+
+    /* convert back to floating value and restore the sign */
+	if((hx|lx)==0) 			/* return sign(x)*0 */
+	    return Zero[(u_int32_t)sx>>31];
+	while(hx<0x00100000) {		/* normalize x */
+	    hx = hx+hx+(lx>>31); lx = lx+lx;
+	    iy -= 1;
+	}
+	if(iy>= -1022) {	/* normalize output */
+	    hx = ((hx-0x00100000)|((iy+1023)<<20));
+	    INSERT_WORDS(x,hx|sx,lx);
+	} else {		/* subnormal output */
+	    n = -1022 - iy;
+	    if(n<=20) {
+		lx = (lx>>n)|((u_int32_t)hx<<(32-n));
+		hx >>= n;
+	    } else if (n<=31) {
+		lx = (hx<<(32-n))|(lx>>n); hx = sx;
+	    } else {
+		lx = hx>>(n-32); hx = sx;
+	    }
+	    INSERT_WORDS(x,hx|sx,lx);
+	    x *= one;		/* create necessary signal */
+	}
+	return x;		/* exact output */
+}
+
+/*
+ * wrapper fmod(x,y)
+ */
+#ifndef _IEEE_LIBM
+double fmod(double x, double y)
+{
+	double z = __ieee754_fmod(x, y);
+	if (_LIB_VERSION == _IEEE_ || isnan(y) || isnan(x))
+		return z;
+	if (y == 0.0)
+		return __kernel_standard(x, y, 27); /* fmod(x,0) */
+	return z;
+}
+#else
+strong_alias(__ieee754_fmod, fmod)
+#endif
+libm_hidden_def(fmod)

src/libm/s_scalbn.c

@@ -61,17 +61,9 @@ double scalbln(double x, long n)
 }
 libm_hidden_def(scalbln)
 
-#if LONG_MAX == INT_MAX
-/* strong_alias(scalbln, scalbn) - "error: conflicting types for 'scalbn'"
- * because it tries to declare "typeof(scalbln) scalbn;"
- * which tries to give "long" parameter to scalbn.
- * Doing it by hand:
- */
-__typeof(scalbn) scalbn __attribute__((alias("scalbln")));
-#else
+
 double scalbn(double x, int n)
 {
 	return scalbln(x, n);
 }
-#endif
 libm_hidden_def(scalbn)