code: plan9front

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ape/libm: add back fmod, remove modf

We removed the wrong file. Put it back.

--- /dev/null

+++ b/sys/src/ape/lib/ap/math/fmod.c

@@ -1,0 +1,27 @@

+/* floating-point mod function without infinity or NaN checking */

+#include <math.h>

+double

+fmod (double x, double y)

+{

+	int sign = 0, yexp;

+	double r, yfr;

+

+	if (y == 0)

+		return 0;

+	if (y < 0)

+		y = -y;

+	yfr = frexp (y, &yexp);

+	if (x < 0) {

+		sign = 1;

+		r = -x;

+	} else

+		r = x;

+	while (r >= y) {

+		int rexp;

+		double rfr = frexp (r, &rexp);

+		r -= ldexp (y, rexp - yexp - (rfr < yfr));

+	}

+	if (sign)

+		r = -r;

+	return r;

+}

--- a/sys/src/ape/lib/ap/math/mkfile

+++ b/sys/src/ape/lib/ap/math/mkfile

@@ -10,6 +10,7 @@

 	fabs.$O\

 	floor.$O\

 	fmin.$O\

+	fmod.$O\

 	gamma.$O\

 	hypot.$O\

 	j0.$O\

--- a/sys/src/ape/lib/ap/math/modf.c

+++ /dev/null

@@ -1,53 +1,0 @@

-#include <math.h>

-#include <errno.h>

-

-/* modf suitable for IEEE double-precision */

-

-#define	MASK	0x7ffL

-#define SIGN	0x80000000

-#define	SHIFT	20

-#define	BIAS	1022L

-

-typedef	union

-{

-	double	d;

-	struct

-	{

-		long	ms;

-		long	ls;

-	} i;

-} Cheat;

-

-double

-modf(double d, double *ip)

-{

-	Cheat x;

-	int e;

-

-	if(-1 < d && d < 1) {

-		*ip = 0;

-		return d;

-	}

-	x.d = d;

-	x.i.ms &= ~SIGN;

-	e = (x.i.ms >> SHIFT) & MASK;

-	if(e == MASK || e == 0){

-		errno = EDOM;

-		*ip = (d > 0)? HUGE_VAL : -HUGE_VAL;

-		return 0;

-	}

-	e -= BIAS;

-	if(e <= SHIFT+1) {

-		x.i.ms &= ~(0x1fffffL >> e);

-		x.i.ls = 0;

-	} else

-	if(e <= SHIFT+33)

-		x.i.ls &= ~(0x7fffffffL >> (e-SHIFT-2));

-	if(d > 0){

-		*ip = x.d;

-		return d - x.d;

-	}else{

-		*ip = -x.d;

-		return d + x.d;

-	}

-}