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Date:      Mon, 3 Jun 2013 17:36:26 +0000 (UTC)
From:      Steve Kargl <kargl@FreeBSD.org>
To:        src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org
Subject:   svn commit: r251321 - in head/lib/msun: ld128 ld80
Message-ID:  <201306031736.r53HaQ8R093348@svn.freebsd.org>
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Author: kargl
Date: Mon Jun  3 17:36:26 2013
New Revision: 251321
URL: http://svnweb.freebsd.org/changeset/base/251321

Log:
  * Rename the polynomial coefficients from P2, P3, ... to A2, A3, ....
    The names now coincide with the name used in PTP Tang's paper.
  
  * Rename the variable from s to tbl to better reflect that
    this is a table, and to be consistent with the naming scheme
    in s_exp2l.c
  
  Reviewed by:	bde (as part of larger diff)

Modified:
  head/lib/msun/ld128/s_expl.c
  head/lib/msun/ld80/s_expl.c

Modified: head/lib/msun/ld128/s_expl.c
==============================================================================
--- head/lib/msun/ld128/s_expl.c	Mon Jun  3 17:34:48 2013	(r251320)
+++ head/lib/msun/ld128/s_expl.c	Mon Jun  3 17:36:26 2013	(r251321)
@@ -52,21 +52,21 @@ twom10000 = 0x1p-10000L,
 u_threshold = -11433.462743336297878837243843452621503L;
 
 static const long double
-P2 = 5.00000000000000000000000000000000000e-1L,
-P3 = 1.66666666666666666666666666666666972e-1L,
-P4 = 4.16666666666666666666666666653708268e-2L,
-P5 = 8.33333333333333333333333315069867254e-3L,
-P6 = 1.38888888888888888888996596213795377e-3L,
-P7 = 1.98412698412698412718821436278644414e-4L,
-P8 = 2.48015873015869681884882576649543128e-5L,
-P9 = 2.75573192240103867817876199544468806e-6L,
-P10 = 2.75573236172670046201884000197885520e-7L,
-P11 = 2.50517544183909126492878226167697856e-8L;
+A2 = 5.00000000000000000000000000000000000e-1L,
+A3 = 1.66666666666666666666666666666666972e-1L,
+A4 = 4.16666666666666666666666666653708268e-2L,
+A5 = 8.33333333333333333333333315069867254e-3L,
+A6 = 1.38888888888888888888996596213795377e-3L,
+A7 = 1.98412698412698412718821436278644414e-4L,
+A8 = 2.48015873015869681884882576649543128e-5L,
+A9 = 2.75573192240103867817876199544468806e-6L,
+A10 = 2.75573236172670046201884000197885520e-7L,
+A11 = 2.50517544183909126492878226167697856e-8L;
 
 static const struct {
 	long double	hi;
 	long double	lo;
-} s[INTERVALS] = {
+} tbl[INTERVALS] = {
 	0x1p0L, 0x0p0L,
 	0x1.0163da9fb33356d84a66aep0L, 0x3.36dcdfa4003ec04c360be2404078p-92L,
 	0x1.02c9a3e778060ee6f7cacap0L, 0x4.f7a29bde93d70a2cabc5cb89ba10p-92L,
@@ -245,10 +245,10 @@ expl(long double x)
 	}
 
 	r = r1 + r2;
-	q = r * r * (P2 + r * (P3 + r * (P4 + r * (P5 + r * (P6 + r * (P7 +
-	    r * (P8 + r * (P9 + r * (P10 + r * P11)))))))));
-	t = s[n2].lo + s[n2].hi;
-	t = s[n2].hi + (s[n2].lo + t * (r2 + q + r1));
+	q = r * r * (A2 + r * (A3 + r * (A4 + r * (A5 + r * (A6 + r * (A7 +
+	    r * (A8 + r * (A9 + r * (A10 + r * A11)))))))));
+	t = tbl[n2].lo + tbl[n2].hi;
+	t = tbl[n2].hi + (tbl[n2].lo + t * (r2 + q + r1));
 
 	/* Scale by 2**k. */
 	if (k >= LDBL_MIN_EXP) {

Modified: head/lib/msun/ld80/s_expl.c
==============================================================================
--- head/lib/msun/ld80/s_expl.c	Mon Jun  3 17:34:48 2013	(r251320)
+++ head/lib/msun/ld80/s_expl.c	Mon Jun  3 17:36:26 2013	(r251321)
@@ -78,11 +78,11 @@ L2 = -3.2819649005320973e-13,		/* -0x171
  * |exp(x) - p(x)| < 2**-77.2
  * (0.002708 is ln2/(2*INTERVALS) rounded up a little).
  */
-P2 =  0.5,
-P3 =  1.6666666666666119e-1,		/*  0x15555555555490.0p-55 */
-P4 =  4.1666666666665887e-2,		/*  0x155555555554e5.0p-57 */
-P5 =  8.3333354987869413e-3,		/*  0x1111115b789919.0p-59 */
-P6 =  1.3888891738560272e-3;		/*  0x16c16c651633ae.0p-62 */
+A2 =  0.5,
+A3 =  1.6666666666666119e-1,		/*  0x15555555555490.0p-55 */
+A4 =  4.1666666666665887e-2,		/*  0x155555555554e5.0p-57 */
+A5 =  8.3333354987869413e-3,		/*  0x1111115b789919.0p-59 */
+A6 =  1.3888891738560272e-3;		/*  0x16c16c651633ae.0p-62 */
 
 /*
  * 2^(i/INTERVALS) for i in [0,INTERVALS] is represented by two values where
@@ -96,8 +96,7 @@ P6 =  1.3888891738560272e-3;		/*  0x16c1
 static const struct {
 	double	hi;
 	double	lo;
-/* XXX should rename 's'. */
-} s[INTERVALS] = {
+} tbl[INTERVALS] = {
 	0x1p+0, 0x0p+0,
 	0x1.0163da9fb3335p+0, 0x1.b61299ab8cdb7p-54,
 	0x1.02c9a3e778060p+0, 0x1.dcdef95949ef4p-53,
@@ -284,14 +283,14 @@ expl(long double x)
 		twopkp10000 = v.e;
 	}
 
-	/* Evaluate expl(midpoint[n2] + r1 + r2) = s[n2] * expl(r1 + r2). */
+	/* Evaluate expl(midpoint[n2] + r1 + r2) = tbl[n2] * expl(r1 + r2). */
 	/* Here q = q(r), not q(r1), since r1 is lopped like L1. */
 	t45 = r * P5 + P4;
 	z = r * r;
 	t23 = r * P3 + P2;
 	q = r2 + z * t23 + z * z * t45 + z * z * z * P6;
-	t = (long double)s[n2].lo + s[n2].hi;
-	t = s[n2].lo + t * (q + r1) + s[n2].hi;
+	t = (long double)tbl[n2].lo + tbl[n2].hi;
+	t = tbl[n2].lo + t * (q + r1) + tbl[n2].hi;
 
 	/* Scale by 2**k. */
 	if (k >= LDBL_MIN_EXP) {

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