don't inline __rem_pio2l so the code size is smaller

1 files changed, 131 insertions, 0 deletions

diff --git a/src/math/__rem_pio2l.c b/src/math/__rem_pio2l.c
new file mode 100644
index 00000000..10af404c
--- /dev/null
+++ b/src/math/__rem_pio2l.c
@@ -0,0 +1,131 @@
+/* origin: FreeBSD /usr/src/lib/msun/ld80/e_rem_pio2.c */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ * Copyright (c) 2008 Steven G. Kargl, David Schultz, Bruce D. Evans.
+ *
+ * Developed at SunSoft, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ *
+ * Optimized by Bruce D. Evans.
+ */
+#include "libm.h"
+#if LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
+/* ld80 version of __rem_pio2(x,y)
+ *
+ * return the remainder of x rem pi/2 in y[0]+y[1]
+ * use __rem_pio2_large() for large x
+ */
+
+#define BIAS    (LDBL_MAX_EXP - 1)
+
+/*
+ * invpio2:  64 bits of 2/pi
+ * pio2_1:   first  39 bits of pi/2
+ * pio2_1t:  pi/2 - pio2_1
+ * pio2_2:   second 39 bits of pi/2
+ * pio2_2t:  pi/2 - (pio2_1+pio2_2)
+ * pio2_3:   third  39 bits of pi/2
+ * pio2_3t:  pi/2 - (pio2_1+pio2_2+pio2_3)
+ */
+static const double
+zero   =  0.00000000000000000000e+00, /* 0x00000000, 0x00000000 */
+two24  =  1.67772160000000000000e+07, /* 0x41700000, 0x00000000 */
+pio2_1 =  1.57079632679597125389e+00, /* 0x3FF921FB, 0x54444000 */
+pio2_2 = -1.07463465549783099519e-12, /* -0x12e7b967674000.0p-92 */
+pio2_3 =  6.36831716351370313614e-25; /*  0x18a2e037074000.0p-133 */
+
+static const long double
+invpio2 =  6.36619772367581343076e-01L, /*  0xa2f9836e4e44152a.0p-64 */
+pio2_1t = -1.07463465549719416346e-12L, /* -0x973dcb3b399d747f.0p-103 */
+pio2_2t =  6.36831716351095013979e-25L, /*  0xc51701b839a25205.0p-144 */
+pio2_3t = -2.75299651904407171810e-37L; /* -0xbb5bf6c7ddd660ce.0p-185 */
+
+int __rem_pio2l(long double x, long double *y)
+{
+	union IEEEl2bits u,u1;
+	long double z,w,t,r,fn;
+	double tx[3],ty[2];
+	int e0,ex,i,j,nx,n;
+	int16_t expsign;
+
+	u.e = x;
+	expsign = u.xbits.expsign;
+	ex = expsign & 0x7fff;
+	if (ex < BIAS + 25 || (ex == BIAS + 25 && u.bits.manh < 0xc90fdaa2)) {
+		union IEEEl2bits u2;
+		int ex1;
+
+		/* |x| ~< 2^25*(pi/2), medium size */
+		/* Use a specialized rint() to get fn.  Assume round-to-nearest. */
+		fn = x*invpio2 + 0x1.8p63;
+		fn = fn - 0x1.8p63;
+// FIXME
+//#ifdef HAVE_EFFICIENT_IRINT
+//		n = irint(fn);
+//#else
+		n = fn;
+//#endif
+		r = x-fn*pio2_1;
+		w = fn*pio2_1t;    /* 1st round good to 102 bit */
+		j = ex;
+		y[0] = r-w;
+		u2.e = y[0];
+		ex1 = u2.xbits.expsign & 0x7fff;
+		i = j-ex1;
+		if (i > 22) {  /* 2nd iteration needed, good to 141 */
+			t = r;
+			w = fn*pio2_2;
+			r = t-w;
+			w = fn*pio2_2t-((t-r)-w);
+			y[0] = r-w;
+			u2.e = y[0];
+			ex1 = u2.xbits.expsign & 0x7fff;
+			i = j-ex1;
+			if (i > 61) {  /* 3rd iteration need, 180 bits acc */
+				t = r; /* will cover all possible cases */
+				w = fn*pio2_3;
+				r = t-w;
+				w = fn*pio2_3t-((t-r)-w);
+				y[0] = r-w;
+			}
+		}
+		y[1] = (r - y[0]) - w;
+		return n;
+	}
+	/*
+	 * all other (large) arguments
+	 */
+	if (ex == 0x7fff) {                /* x is inf or NaN */
+		y[0] = y[1] = x - x;
+		return 0;
+	}
+	/* set z = scalbn(|x|,ilogb(x)-23) */
+	u1.e = x;
+	e0 = ex - BIAS - 23;            /* e0 = ilogb(|x|)-23; */
+	u1.xbits.expsign = ex - e0;
+	z = u1.e;
+	for (i=0; i<2; i++) {
+		tx[i] = (double)(int32_t)z;
+		z     = (z-tx[i])*two24;
+	}
+	tx[2] = z;
+	nx = 3;
+	while (tx[nx-1] == zero)
+		nx--;     /* skip zero term */
+	n = __rem_pio2_large(tx,ty,e0,nx,2);
+	r = (long double)ty[0] + ty[1];
+	w = ty[1] - (r - ty[0]);
+	if (expsign < 0) {
+		y[0] = -r;
+		y[1] = -w;
+		return -n;
+	}
+	y[0] = r;
+	y[1] = w;
+	return n;
+}
+#endif