Upgrade libm.
This brings us up to date with FreeBSD HEAD, fixes various bugs, unifies
the set of functions we support on ARM, MIPS, and x86, fixes "long double",
adds ISO C99 support, and adds basic unit tests.
It turns out that our "long double" functions have always been broken
for non-normal numbers. This patch fixes that by not using the upstream
implementations and just forwarding to the regular "double" implementation
instead (since "long double" on Android is just "double" anyway, which is
what BSD doesn't support).
All the tests pass on ARM, MIPS, and x86, plus glibc on x86-64.
Bug: 3169850
Bug: 8012787
Bug: https://code.google.com/p/android/issues/detail?id=6697
Change-Id: If0c343030959c24bfc50d4d21c9530052c581837
diff --git a/libm/upstream-freebsd/lib/msun/src/e_atan2l.c b/libm/upstream-freebsd/lib/msun/src/e_atan2l.c
new file mode 100644
index 0000000..0326482
--- /dev/null
+++ b/libm/upstream-freebsd/lib/msun/src/e_atan2l.c
@@ -0,0 +1,120 @@
+
+/* @(#)e_atan2.c 1.3 95/01/18 */
+/* FreeBSD: head/lib/msun/src/e_atan2.c 176451 2008-02-22 02:30:36Z das */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * 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.
+ * ====================================================
+ *
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+/*
+ * See comments in e_atan2.c.
+ * Converted to long double by David Schultz <das@FreeBSD.ORG>.
+ */
+
+#include <float.h>
+
+#include "invtrig.h"
+#include "math.h"
+#include "math_private.h"
+
+static volatile long double
+tiny = 1.0e-300;
+static const long double
+zero = 0.0;
+
+#ifdef __i386__
+/* XXX Work around the fact that gcc truncates long double constants on i386 */
+static volatile double
+pi1 = 3.14159265358979311600e+00, /* 0x1.921fb54442d18p+1 */
+pi2 = 1.22514845490862001043e-16; /* 0x1.1a80000000000p-53 */
+#define pi ((long double)pi1 + pi2)
+#else
+static const long double
+pi = 3.14159265358979323846264338327950280e+00L;
+#endif
+
+long double
+atan2l(long double y, long double x)
+{
+ union IEEEl2bits ux, uy;
+ long double z;
+ int32_t k,m;
+ int16_t exptx, expsignx, expty, expsigny;
+
+ uy.e = y;
+ expsigny = uy.xbits.expsign;
+ expty = expsigny & 0x7fff;
+ ux.e = x;
+ expsignx = ux.xbits.expsign;
+ exptx = expsignx & 0x7fff;
+
+ if ((exptx==BIAS+LDBL_MAX_EXP &&
+ ((ux.bits.manh&~LDBL_NBIT)|ux.bits.manl)!=0) || /* x is NaN */
+ (expty==BIAS+LDBL_MAX_EXP &&
+ ((uy.bits.manh&~LDBL_NBIT)|uy.bits.manl)!=0)) /* y is NaN */
+ return x+y;
+ if (expsignx==BIAS && ((ux.bits.manh&~LDBL_NBIT)|ux.bits.manl)==0)
+ return atanl(y); /* x=1.0 */
+ m = ((expsigny>>15)&1)|((expsignx>>14)&2); /* 2*sign(x)+sign(y) */
+
+ /* when y = 0 */
+ if(expty==0 && ((uy.bits.manh&~LDBL_NBIT)|uy.bits.manl)==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(exptx==0 && ((ux.bits.manh&~LDBL_NBIT)|ux.bits.manl)==0)
+ return (expsigny<0)? -pio2_hi-tiny: pio2_hi+tiny;
+
+ /* when x is INF */
+ if(exptx==BIAS+LDBL_MAX_EXP) {
+ if(expty==BIAS+LDBL_MAX_EXP) {
+ switch(m) {
+ case 0: return pio2_hi*0.5+tiny;/* atan(+INF,+INF) */
+ case 1: return -pio2_hi*0.5-tiny;/* atan(-INF,+INF) */
+ case 2: return 1.5*pio2_hi+tiny;/*atan(+INF,-INF)*/
+ case 3: return -1.5*pio2_hi-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(expty==BIAS+LDBL_MAX_EXP)
+ return (expsigny<0)? -pio2_hi-tiny: pio2_hi+tiny;
+
+ /* compute y/x */
+ k = expty-exptx;
+ if(k > LDBL_MANT_DIG+2) { /* |y/x| huge */
+ z=pio2_hi+pio2_lo;
+ m&=1;
+ }
+ else if(expsignx<0&&k<-LDBL_MANT_DIG-2) z=0.0; /* |y/x| tiny, x<0 */
+ else z=atanl(fabsl(y/x)); /* safe to do y/x */
+ switch (m) {
+ case 0: return z ; /* atan(+,+) */
+ case 1: return -z ; /* atan(-,+) */
+ case 2: return pi-(z-pi_lo);/* atan(+,-) */
+ default: /* case 3 */
+ return (z-pi_lo)-pi;/* atan(-,-) */
+ }
+}