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authorUlrich Drepper <drepper@redhat.com>2001-04-05 05:29:26 +0000
committerUlrich Drepper <drepper@redhat.com>2001-04-05 05:29:26 +0000
commitb53df4c940bdfb4a23e065c7b3a919b4ed054f03 (patch)
treebce7ee6a6eb5cb69304b420bf20647656bb4e344 /sysdeps/ieee754
parent817a51e296ac7335b8e161756dbc18012f86f4cd (diff)
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Update.
	* sysdeps/unix/sysv/aix/dl-libc.c: Don't use the ELF version,
	define simple replacements here.  Patch by Michael Keezer.

	* sysdeps/ieee754/ldbl-128/e_logl.c: New file.
	* sysdeps/ieee754/ldbl-96/e_asinl.c: New file.
	Contributed by Stephen L Moshier <moshier@mediaone.net>.
Diffstat (limited to 'sysdeps/ieee754')
-rw-r--r--sysdeps/ieee754/ldbl-128/e_logl.c270
-rw-r--r--sysdeps/ieee754/ldbl-96/e_asinl.c144
2 files changed, 414 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128/e_logl.c b/sysdeps/ieee754/ldbl-128/e_logl.c
new file mode 100644
index 0000000000..a17c745413
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128/e_logl.c
@@ -0,0 +1,270 @@
+/*							logll.c
+ *
+ * Natural logarithm for 128-bit long double precision.
+ *
+ *
+ *
+ * SYNOPSIS:
+ *
+ * long double x, y, logl();
+ *
+ * y = logl( x );
+ *
+ *
+ *
+ * DESCRIPTION:
+ *
+ * Returns the base e (2.718...) logarithm of x.
+ *
+ * The argument is separated into its exponent and fractional
+ * parts.  Use of a lookup table increases the speed of the routine.
+ * The program uses logarithms tabulated at intervals of 1/128 to
+ * cover the domain from approximately 0.7 to 1.4.
+ *
+ * On the interval [-1/128, +1/128] the logarithm of 1+x is approximated by
+ *     log(1+x) = x - 0.5 x^2 + x^3 P(x) .
+ *
+ *
+ *
+ * ACCURACY:
+ *
+ *                      Relative error:
+ * arithmetic   domain     # trials      peak         rms
+ *    IEEE   0.875, 1.125   100000      1.2e-34    4.1e-35
+ *    IEEE   0.125, 8       100000      1.2e-34    4.1e-35
+ *
+ *
+ * WARNING:
+ *
+ * This program uses integer operations on bit fields of floating-point
+ * numbers.  It does not work with data structures other than the
+ * structure assumed.
+ *
+ */
+
+/* Copyright 2001 by Stephen L. Moshier <moshier@na-net.ornl.gov> */
+
+#include "math_private.h"
+
+/* log(1+x) = x - .5 x^2 + x^3 l(x)
+   -.0078125 <= x <= +.0078125
+   peak relative error 1.2e-37 */
+static const long double
+l3 =   3.333333333333333333333333333333336096926E-1L,
+l4 =  -2.499999999999999999999999999486853077002E-1L,
+l5 =   1.999999999999999999999999998515277861905E-1L,
+l6 =  -1.666666666666666666666798448356171665678E-1L,
+l7 =   1.428571428571428571428808945895490721564E-1L,
+l8 =  -1.249999999999999987884655626377588149000E-1L,
+l9 =   1.111111111111111093947834982832456459186E-1L,
+l10 = -1.000000000000532974938900317952530453248E-1L,
+l11 =  9.090909090915566247008015301349979892689E-2L,
+l12 = -8.333333211818065121250921925397567745734E-2L,
+l13 =  7.692307559897661630807048686258659316091E-2L,
+l14 = -7.144242754190814657241902218399056829264E-2L,
+l15 =  6.668057591071739754844678883223432347481E-2L;
+
+/* Lookup table of ln(t) - (t-1)
+    t = 0.5 + (k+26)/128)
+    k = 0, ..., 91   */
+static const long double logtbl[92] = {
+-5.5345593589352099112142921677820359632418E-2L,
+-5.2108257402767124761784665198737642086148E-2L,
+-4.8991686870576856279407775480686721935120E-2L,
+-4.5993270766361228596215288742353061431071E-2L,
+-4.3110481649613269682442058976885699556950E-2L,
+-4.0340872319076331310838085093194799765520E-2L,
+-3.7682072451780927439219005993827431503510E-2L,
+-3.5131785416234343803903228503274262719586E-2L,
+-3.2687785249045246292687241862699949178831E-2L,
+-3.0347913785027239068190798397055267411813E-2L,
+-2.8110077931525797884641940838507561326298E-2L,
+-2.5972247078357715036426583294246819637618E-2L,
+-2.3932450635346084858612873953407168217307E-2L,
+-2.1988775689981395152022535153795155900240E-2L,
+-2.0139364778244501615441044267387667496733E-2L,
+-1.8382413762093794819267536615342902718324E-2L,
+-1.6716169807550022358923589720001638093023E-2L,
+-1.5138929457710992616226033183958974965355E-2L,
+-1.3649036795397472900424896523305726435029E-2L,
+-1.2244881690473465543308397998034325468152E-2L,
+-1.0924898127200937840689817557742469105693E-2L,
+-9.6875626072830301572839422532631079809328E-3L,
+-8.5313926245226231463436209313499745894157E-3L,
+-7.4549452072765973384933565912143044991706E-3L,
+-6.4568155251217050991200599386801665681310E-3L,
+-5.5356355563671005131126851708522185605193E-3L,
+-4.6900728132525199028885749289712348829878E-3L,
+-3.9188291218610470766469347968659624282519E-3L,
+-3.2206394539524058873423550293617843896540E-3L,
+-2.5942708080877805657374888909297113032132E-3L,
+-2.0385211375711716729239156839929281289086E-3L,
+-1.5522183228760777967376942769773768850872E-3L,
+-1.1342191863606077520036253234446621373191E-3L,
+-7.8340854719967065861624024730268350459991E-4L,
+-4.9869831458030115699628274852562992756174E-4L,
+-2.7902661731604211834685052867305795169688E-4L,
+-1.2335696813916860754951146082826952093496E-4L,
+-3.0677461025892873184042490943581654591817E-5L,
+ 0.0000000000000000000000000000000000000000E0L,
+-3.0359557945051052537099938863236321874198E-5L,
+-1.2081346403474584914595395755316412213151E-4L,
+-2.7044071846562177120083903771008342059094E-4L,
+-4.7834133324631162897179240322783590830326E-4L,
+-7.4363569786340080624467487620270965403695E-4L,
+-1.0654639687057968333207323853366578860679E-3L,
+-1.4429854811877171341298062134712230604279E-3L,
+-1.8753781835651574193938679595797367137975E-3L,
+-2.3618380914922506054347222273705859653658E-3L,
+-2.9015787624124743013946600163375853631299E-3L,
+-3.4938307889254087318399313316921940859043E-3L,
+-4.1378413103128673800485306215154712148146E-3L,
+-4.8328735414488877044289435125365629849599E-3L,
+-5.5782063183564351739381962360253116934243E-3L,
+-6.3731336597098858051938306767880719015261E-3L,
+-7.2169643436165454612058905294782949315193E-3L,
+-8.1090214990427641365934846191367315083867E-3L,
+-9.0486422112807274112838713105168375482480E-3L,
+-1.0035177140880864314674126398350812606841E-2L,
+-1.1067990155502102718064936259435676477423E-2L,
+-1.2146457974158024928196575103115488672416E-2L,
+-1.3269969823361415906628825374158424754308E-2L,
+-1.4437927104692837124388550722759686270765E-2L,
+-1.5649743073340777659901053944852735064621E-2L,
+-1.6904842527181702880599758489058031645317E-2L,
+-1.8202661505988007336096407340750378994209E-2L,
+-1.9542647000370545390701192438691126552961E-2L,
+-2.0924256670080119637427928803038530924742E-2L,
+-2.2346958571309108496179613803760727786257E-2L,
+-2.3810230892650362330447187267648486279460E-2L,
+-2.5313561699385640380910474255652501521033E-2L,
+-2.6856448685790244233704909690165496625399E-2L,
+-2.8438398935154170008519274953860128449036E-2L,
+-3.0058928687233090922411781058956589863039E-2L,
+-3.1717563112854831855692484086486099896614E-2L,
+-3.3413836095418743219397234253475252001090E-2L,
+-3.5147290019036555862676702093393332533702E-2L,
+-3.6917475563073933027920505457688955423688E-2L,
+-3.8723951502862058660874073462456610731178E-2L,
+-4.0566284516358241168330505467000838017425E-2L,
+-4.2444048996543693813649967076598766917965E-2L,
+-4.4356826869355401653098777649745233339196E-2L,
+-4.6304207416957323121106944474331029996141E-2L,
+-4.8285787106164123613318093945035804818364E-2L,
+-5.0301169421838218987124461766244507342648E-2L,
+-5.2349964705088137924875459464622098310997E-2L,
+-5.4431789996103111613753440311680967840214E-2L,
+-5.6546268881465384189752786409400404404794E-2L,
+-5.8693031345788023909329239565012647817664E-2L,
+-6.0871713627532018185577188079210189048340E-2L,
+-6.3081958078862169742820420185833800925568E-2L,
+-6.5323413029406789694910800219643791556918E-2L,
+-6.7595732653791419081537811574227049288168E-2L
+};
+
+/* ln(2) = ln2a + ln2b with extended precision. */
+static const long double
+  ln2a = 6.93145751953125e-1L,
+  ln2b = 1.4286068203094172321214581765680755001344E-6L;
+
+
+long double
+__ieee754_logl(long double x)
+{
+  long double z, y, w;
+  ieee854_long_double_shape_type u, t;
+  unsigned int m;
+  int k, e;
+
+  u.value = x;
+  m = u.parts32.w0;
+
+  /* Check for IEEE special cases.  */
+  k = m & 0x7fffffff;
+  /* log(0) = -infinity. */
+  if ((k | u.parts32.w1 | u.parts32.w2 | u.parts32.w3) == 0)
+    {
+      u.parts32.w0 = 0xffff;
+      return u.value;
+    }
+  /* log ( x < 0 ) = NaN */
+  if (m & 0x80000000)
+    {
+      u.parts32.w0 = 0x7fff;
+      u.parts32.w1 = 0xffff;
+      u.parts32.w2 = 0xffff;
+      u.parts32.w3 = 0xffff;
+      return u.value;
+    }
+  /* log (infinity or NaN) */
+  if (k >= 0x7fff0000)
+    {
+      return u.value;
+    }
+
+  /* Extract exponent and reduce domain to 0.703125 <= u < 1.40625  */
+  e = (int) (m >> 16) - (int) 0x3ffe;
+  m &= 0xffff;
+  u.parts32.w0 = m | 0x3ffe0000;
+  m |= 0x10000;
+  /* Find lookup table index k from high order bits of the significand. */
+  if (m < 0x16800)
+    {
+      k = (m - 0xff00) >> 9;
+      /* t is the argument 0.5 + (k+26)/128
+	 of the nearest item to u in the lookup table.  */
+      t.parts32.w0 = 0x3fff0000 + (k << 9);
+      t.parts32.w1 = 0;
+      t.parts32.w2 = 0;
+      t.parts32.w3 = 0;
+      u.parts32.w0 += 0x10000;
+      e -= 1;
+      k += 64;
+    }
+  else
+    {
+      k = (m - 0xfe00) >> 10;
+      t.parts32.w0 = 0x3ffe0000 + (k << 10);
+      t.parts32.w1 = 0;
+      t.parts32.w2 = 0;
+      t.parts32.w3 = 0;
+    }
+  /* On this interval the table is not used due to cancellation error.  */
+  if ((x <= 1.0078125L) && (x >= 0.9921875L))
+    {
+      z = x - 1.0L;
+      k = 64;
+      t.value  = 1.0L;
+      e = 0;
+    }
+  else
+    {
+      /* log(u) = log( t u/t ) = log(t) + log(u/t)
+	 log(t) is tabulated in the lookup table.
+	 Express log(u/t) = log(1+z),  where z = u/t - 1 = (u-t)/t.
+         cf. Cody & Waite. */
+      z = (u.value - t.value) / t.value;
+    }
+  /* Series expansion of log(1+z).  */
+  w = z * z;
+  y = ((((((((((((l15 * z
+		  + l14) * z
+		 + l13) * z
+		+ l12) * z
+	       + l11) * z
+	      + l10) * z
+	     + l9) * z
+	    + l8) * z
+	   + l7) * z
+	  + l6) * z
+	 + l5) * z
+	+ l4) * z
+       + l3) * z * w;
+  y -= 0.5 * w;
+  y += e * ln2b;  /* Base 2 exponent offset times ln(2).  */
+  y += z;
+  y += logtbl[k-26]; /* log(t) - (t-1) */
+  y += (t.value - 1.0L);
+  y += e * ln2a;
+  return y;
+}
diff --git a/sysdeps/ieee754/ldbl-96/e_asinl.c b/sysdeps/ieee754/ldbl-96/e_asinl.c
new file mode 100644
index 0000000000..f5d817b53a
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-96/e_asinl.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.
+ * ====================================================
+ */
+
+/*
+  Long double expansions contributed by
+  Stephen L. Moshier <moshier@na-net.ornl.gov>
+*/
+
+/* __ieee754_asin(x)
+ * Method :
+ *	Since  asin(x) = x + x^3/6 + x^5*3/40 + x^7*15/336 + ...
+ *	we approximate asin(x) on [0,0.5] by
+ *		asin(x) = x + x*x^2*R(x^2)
+ *
+ *	For x in [0.5,1]
+ *		asin(x) = pi/2-2*asin(sqrt((1-x)/2))
+ *	Let y = (1-x), z = y/2, s := sqrt(z), and pio2_hi+pio2_lo=pi/2;
+ *	then for x>0.98
+ *		asin(x) = pi/2 - 2*(s+s*z*R(z))
+ *			= pio2_hi - (2*(s+s*z*R(z)) - pio2_lo)
+ *	For x<=0.98, let pio4_hi = pio2_hi/2, then
+ *		f = hi part of s;
+ *		c = sqrt(z) - f = (z-f*f)/(s+f) 	...f+c=sqrt(z)
+ *	and
+ *		asin(x) = pi/2 - 2*(s+s*z*R(z))
+ *			= pio4_hi+(pio4-2s)-(2s*z*R(z)-pio2_lo)
+ *			= pio4_hi+(pio4-2f)-(2s*z*R(z)-(pio2_lo+2c))
+ *
+ * Special cases:
+ *	if x is NaN, return x itself;
+ *	if |x|>1, return NaN with invalid signal.
+ *
+ */
+
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const long double
+#else
+static long double
+#endif
+  one = 1.0L,
+  huge = 1.0e+4932L,
+ pio2_hi = 1.5707963267948966192021943710788178805159986950457096099853515625L,
+  pio2_lo = 2.9127320560933561582586004641843300502121E-20L,
+  pio4_hi = 7.8539816339744830960109718553940894025800E-1L,
+
+	/* coefficient for R(x^2) */
+
+  /* asin(x) = x + x^3 pS(x^2) / qS(x^2)
+     0 <= x <= 0.5
+     peak relative error 1.9e-21  */
+  pS0 =  -1.008714657938491626019651170502036851607E1L,
+  pS1 =   2.331460313214179572063441834101394865259E1L,
+  pS2 =  -1.863169762159016144159202387315381830227E1L,
+  pS3 =   5.930399351579141771077475766877674661747E0L,
+  pS4 =  -6.121291917696920296944056882932695185001E-1L,
+  pS5 =   3.776934006243367487161248678019350338383E-3L,
+
+  qS0 =  -6.052287947630949712886794360635592886517E1L,
+  qS1 =   1.671229145571899593737596543114258558503E2L,
+  qS2 =  -1.707840117062586426144397688315411324388E2L,
+  qS3 =   7.870295154902110425886636075950077640623E1L,
+  qS4 =  -1.568433562487314651121702982333303458814E1L;
+    /* 1.000000000000000000000000000000000000000E0 */
+
+#ifdef __STDC__
+long double
+__ieee754_asinl (long double x)
+#else
+double
+__ieee754_asinl (x)
+     long double x;
+#endif
+{
+  long double t, w, p, q, c, r, s;
+  int32_t ix;
+  u_int32_t se, i0, i1, k;
+
+  GET_LDOUBLE_WORDS (se, i0, i1, x);
+  ix = se & 0x7fff;
+  ix = (ix << 16) | (i0 >> 16);
+  if (ix >= 0x3fff8000)
+    {				/* |x|>= 1 */
+      if (((i0 - 0x80000000) | i1) == 0)
+	/* asin(1)=+-pi/2 with inexact */
+	return x * pio2_hi + x * pio2_lo;
+      return (x - x) / (x - x);	/* asin(|x|>1) is NaN */
+    }
+  else if (ix < 0x3ffe8000)
+    {				/* |x|<0.5 */
+      if (ix < 0x3fde8000)
+	{			/* if |x| < 2**-33 */
+	  if (huge + x > one)
+	    return x;		/* return x with inexact if x!=0 */
+	}
+      else
+	{
+	  t = x * x;
+	  p =
+	    t * (pS0 +
+		 t * (pS1 + t * (pS2 + t * (pS3 + t * (pS4 + t * pS5)))));
+	  q = qS0 + t * (qS1 + t * (qS2 + t * (qS3 + t * (qS4 + t))));
+	  w = p / q;
+	  return x + x * w;
+	}
+    }
+  /* 1> |x|>= 0.5 */
+  w = one - fabsl (x);
+  t = w * 0.5;
+  p = t * (pS0 + t * (pS1 + t * (pS2 + t * (pS3 + t * (pS4 + t * pS5)))));
+  q = qS0 + t * (qS1 + t * (qS2 + t * (qS3 + t * (qS4 + t))));
+  s = __ieee754_sqrtl (t);
+  if (ix >= 0x3ffef999)
+    {				/* if |x| > 0.975 */
+      w = p / q;
+      t = pio2_hi - (2.0 * (s + s * w) - pio2_lo);
+    }
+  else
+    {
+      GET_LDOUBLE_WORDS (k, i0, i1, s);
+      i1 = 0;
+      SET_LDOUBLE_WORDS (w,k,i0,i1);
+      c = (t - w * w) / (s + w);
+      r = p / q;
+      p = 2.0 * s * r - (pio2_lo - 2.0 * c);
+      q = pio4_hi - 2.0 * w;
+      t = pio4_hi - (p - q);
+    }
+  if ((se & 0x8000) == 0)
+    return t;
+  else
+    return -t;
+}