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diff --git a/libquadmath/math/powq.c b/libquadmath/math/powq.c
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+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* Expansions and modifications for 128-bit long double are
+ Copyright (C) 2001 Stephen L. Moshier <moshier@na-net.ornl.gov>
+ and are incorporated herein by permission of the author. The author
+ reserves the right to distribute this material elsewhere under different
+ copying permissions. These modifications are distributed here under
+ the following terms:
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
+
+/* __ieee754_powl(x,y) return x**y
+ *
+ * n
+ * Method: Let x = 2 * (1+f)
+ * 1. Compute and return log2(x) in two pieces:
+ * log2(x) = w1 + w2,
+ * where w1 has 113-53 = 60 bit trailing zeros.
+ * 2. Perform y*log2(x) = n+y' by simulating muti-precision
+ * arithmetic, where |y'|<=0.5.
+ * 3. Return x**y = 2**n*exp(y'*log2)
+ *
+ * Special cases:
+ * 1. (anything) ** 0 is 1
+ * 2. (anything) ** 1 is itself
+ * 3. (anything) ** NAN is NAN
+ * 4. NAN ** (anything except 0) is NAN
+ * 5. +-(|x| > 1) ** +INF is +INF
+ * 6. +-(|x| > 1) ** -INF is +0
+ * 7. +-(|x| < 1) ** +INF is +0
+ * 8. +-(|x| < 1) ** -INF is +INF
+ * 9. +-1 ** +-INF is NAN
+ * 10. +0 ** (+anything except 0, NAN) is +0
+ * 11. -0 ** (+anything except 0, NAN, odd integer) is +0
+ * 12. +0 ** (-anything except 0, NAN) is +INF
+ * 13. -0 ** (-anything except 0, NAN, odd integer) is +INF
+ * 14. -0 ** (odd integer) = -( +0 ** (odd integer) )
+ * 15. +INF ** (+anything except 0,NAN) is +INF
+ * 16. +INF ** (-anything except 0,NAN) is +0
+ * 17. -INF ** (anything) = -0 ** (-anything)
+ * 18. (-anything) ** (integer) is (-1)**(integer)*(+anything**integer)
+ * 19. (-anything except 0 and inf) ** (non-integer) is NAN
+ *
+ */
+
+#include "quadmath-imp.h"
+
+static const __float128 bp[] = {
+ 1.0Q,
+ 1.5Q,
+};
+
+/* log_2(1.5) */
+static const __float128 dp_h[] = {
+ 0.0,
+ 5.8496250072115607565592654282227158546448E-1Q
+};
+
+/* Low part of log_2(1.5) */
+static const __float128 dp_l[] = {
+ 0.0,
+ 1.0579781240112554492329533686862998106046E-16Q
+};
+
+static const __float128 zero = 0.0Q,
+ one = 1.0Q,
+ two = 2.0Q,
+ two113 = 1.0384593717069655257060992658440192E34Q,
+ huge = 1.0e3000Q,
+ tiny = 1.0e-3000Q;
+
+/* 3/2 log x = 3 z + z^3 + z^3 (z^2 R(z^2))
+ z = (x-1)/(x+1)
+ 1 <= x <= 1.25
+ Peak relative error 2.3e-37 */
+static const __float128 LN[] =
+{
+ -3.0779177200290054398792536829702930623200E1Q,
+ 6.5135778082209159921251824580292116201640E1Q,
+ -4.6312921812152436921591152809994014413540E1Q,
+ 1.2510208195629420304615674658258363295208E1Q,
+ -9.9266909031921425609179910128531667336670E-1Q
+};
+static const __float128 LD[] =
+{
+ -5.129862866715009066465422805058933131960E1Q,
+ 1.452015077564081884387441590064272782044E2Q,
+ -1.524043275549860505277434040464085593165E2Q,
+ 7.236063513651544224319663428634139768808E1Q,
+ -1.494198912340228235853027849917095580053E1Q
+ /* 1.0E0 */
+};
+
+/* exp(x) = 1 + x - x / (1 - 2 / (x - x^2 R(x^2)))
+ 0 <= x <= 0.5
+ Peak relative error 5.7e-38 */
+static const __float128 PN[] =
+{
+ 5.081801691915377692446852383385968225675E8Q,
+ 9.360895299872484512023336636427675327355E6Q,
+ 4.213701282274196030811629773097579432957E4Q,
+ 5.201006511142748908655720086041570288182E1Q,
+ 9.088368420359444263703202925095675982530E-3Q,
+};
+static const __float128 PD[] =
+{
+ 3.049081015149226615468111430031590411682E9Q,
+ 1.069833887183886839966085436512368982758E8Q,
+ 8.259257717868875207333991924545445705394E5Q,
+ 1.872583833284143212651746812884298360922E3Q,
+ /* 1.0E0 */
+};
+
+static const __float128
+ /* ln 2 */
+ lg2 = 6.9314718055994530941723212145817656807550E-1Q,
+ lg2_h = 6.9314718055994528622676398299518041312695E-1Q,
+ lg2_l = 2.3190468138462996154948554638754786504121E-17Q,
+ ovt = 8.0085662595372944372e-0017Q,
+ /* 2/(3*log(2)) */
+ cp = 9.6179669392597560490661645400126142495110E-1Q,
+ cp_h = 9.6179669392597555432899980587535537779331E-1Q,
+ cp_l = 5.0577616648125906047157785230014751039424E-17Q;
+
+__float128
+powq (__float128 x, __float128 y)
+{
+ __float128 z, ax, z_h, z_l, p_h, p_l;
+ __float128 y1, t1, t2, r, s, t, u, v, w;
+ __float128 s2, s_h, s_l, t_h, t_l;
+ int32_t i, j, k, yisint, n;
+ uint32_t ix, iy;
+ int32_t hx, hy;
+ ieee854_float128 o, p, q;
+
+ p.value = x;
+ hx = p.words32.w0;
+ ix = hx & 0x7fffffff;
+
+ q.value = y;
+ hy = q.words32.w0;
+ iy = hy & 0x7fffffff;
+
+
+ /* y==zero: x**0 = 1 */
+ if ((iy | q.words32.w1 | q.words32.w2 | q.words32.w3) == 0)
+ return one;
+
+ /* 1.0**y = 1; -1.0**+-Inf = 1 */
+ if (x == one)
+ return one;
+ if (x == -1.0Q && iy == 0x7fff0000
+ && (q.words32.w1 | q.words32.w2 | q.words32.w3) == 0)
+ return one;
+
+ /* +-NaN return x+y */
+ if ((ix > 0x7fff0000)
+ || ((ix == 0x7fff0000)
+ && ((p.words32.w1 | p.words32.w2 | p.words32.w3) != 0))
+ || (iy > 0x7fff0000)
+ || ((iy == 0x7fff0000)
+ && ((q.words32.w1 | q.words32.w2 | q.words32.w3) != 0)))
+ return x + y;
+
+ /* determine if y is an odd int when x < 0
+ * yisint = 0 ... y is not an integer
+ * yisint = 1 ... y is an odd int
+ * yisint = 2 ... y is an even int
+ */
+ yisint = 0;
+ if (hx < 0)
+ {
+ if (iy >= 0x40700000) /* 2^113 */
+ yisint = 2; /* even integer y */
+ else if (iy >= 0x3fff0000) /* 1.0 */
+ {
+ if (floorq (y) == y)
+ {
+ z = 0.5 * y;
+ if (floorq (z) == z)
+ yisint = 2;
+ else
+ yisint = 1;
+ }
+ }
+ }
+
+ /* special value of y */
+ if ((q.words32.w1 | q.words32.w2 | q.words32.w3) == 0)
+ {
+ if (iy == 0x7fff0000) /* y is +-inf */
+ {
+ if (((ix - 0x3fff0000) | p.words32.w1 | p.words32.w2 | p.words32.w3)
+ == 0)
+ return y - y; /* +-1**inf is NaN */
+ else if (ix >= 0x3fff0000) /* (|x|>1)**+-inf = inf,0 */
+ return (hy >= 0) ? y : zero;
+ else /* (|x|<1)**-,+inf = inf,0 */
+ return (hy < 0) ? -y : zero;
+ }
+ if (iy == 0x3fff0000)
+ { /* y is +-1 */
+ if (hy < 0)
+ return one / x;
+ else
+ return x;
+ }
+ if (hy == 0x40000000)
+ return x * x; /* y is 2 */
+ if (hy == 0x3ffe0000)
+ { /* y is 0.5 */
+ if (hx >= 0) /* x >= +0 */
+ return sqrtq (x);
+ }
+ }
+
+ ax = fabsq (x);
+ /* special value of x */
+ if ((p.words32.w1 | p.words32.w2 | p.words32.w3) == 0)
+ {
+ if (ix == 0x7fff0000 || ix == 0 || ix == 0x3fff0000)
+ {
+ z = ax; /*x is +-0,+-inf,+-1 */
+ if (hy < 0)
+ z = one / z; /* z = (1/|x|) */
+ if (hx < 0)
+ {
+ if (((ix - 0x3fff0000) | yisint) == 0)
+ {
+ z = (z - z) / (z - z); /* (-1)**non-int is NaN */
+ }
+ else if (yisint == 1)
+ z = -z; /* (x<0)**odd = -(|x|**odd) */
+ }
+ return z;
+ }
+ }
+
+ /* (x<0)**(non-int) is NaN */
+ if (((((uint32_t) hx >> 31) - 1) | yisint) == 0)
+ return (x - x) / (x - x);
+
+ /* |y| is huge.
+ 2^-16495 = 1/2 of smallest representable value.
+ If (1 - 1/131072)^y underflows, y > 1.4986e9 */
+ if (iy > 0x401d654b)
+ {
+ /* if (1 - 2^-113)^y underflows, y > 1.1873e38 */
+ if (iy > 0x407d654b)
+ {
+ if (ix <= 0x3ffeffff)
+ return (hy < 0) ? huge * huge : tiny * tiny;
+ if (ix >= 0x3fff0000)
+ return (hy > 0) ? huge * huge : tiny * tiny;
+ }
+ /* over/underflow if x is not close to one */
+ if (ix < 0x3ffeffff)
+ return (hy < 0) ? huge * huge : tiny * tiny;
+ if (ix > 0x3fff0000)
+ return (hy > 0) ? huge * huge : tiny * tiny;
+ }
+
+ n = 0;
+ /* take care subnormal number */
+ if (ix < 0x00010000)
+ {
+ ax *= two113;
+ n -= 113;
+ o.value = ax;
+ ix = o.words32.w0;
+ }
+ n += ((ix) >> 16) - 0x3fff;
+ j = ix & 0x0000ffff;
+ /* determine interval */
+ ix = j | 0x3fff0000; /* normalize ix */
+ if (j <= 0x3988)
+ k = 0; /* |x|<sqrt(3/2) */
+ else if (j < 0xbb67)
+ k = 1; /* |x|<sqrt(3) */
+ else
+ {
+ k = 0;
+ n += 1;
+ ix -= 0x00010000;
+ }
+
+ o.value = ax;
+ o.words32.w0 = ix;
+ ax = o.value;
+
+ /* compute s = s_h+s_l = (x-1)/(x+1) or (x-1.5)/(x+1.5) */
+ u = ax - bp[k]; /* bp[0]=1.0, bp[1]=1.5 */
+ v = one / (ax + bp[k]);
+ s = u * v;
+ s_h = s;
+
+ o.value = s_h;
+ o.words32.w3 = 0;
+ o.words32.w2 &= 0xf8000000;
+ s_h = o.value;
+ /* t_h=ax+bp[k] High */
+ t_h = ax + bp[k];
+ o.value = t_h;
+ o.words32.w3 = 0;
+ o.words32.w2 &= 0xf8000000;
+ t_h = o.value;
+ t_l = ax - (t_h - bp[k]);
+ s_l = v * ((u - s_h * t_h) - s_h * t_l);
+ /* compute log(ax) */
+ s2 = s * s;
+ u = LN[0] + s2 * (LN[1] + s2 * (LN[2] + s2 * (LN[3] + s2 * LN[4])));
+ v = LD[0] + s2 * (LD[1] + s2 * (LD[2] + s2 * (LD[3] + s2 * (LD[4] + s2))));
+ r = s2 * s2 * u / v;
+ r += s_l * (s_h + s);
+ s2 = s_h * s_h;
+ t_h = 3.0 + s2 + r;
+ o.value = t_h;
+ o.words32.w3 = 0;
+ o.words32.w2 &= 0xf8000000;
+ t_h = o.value;
+ t_l = r - ((t_h - 3.0) - s2);
+ /* u+v = s*(1+...) */
+ u = s_h * t_h;
+ v = s_l * t_h + t_l * s;
+ /* 2/(3log2)*(s+...) */
+ p_h = u + v;
+ o.value = p_h;
+ o.words32.w3 = 0;
+ o.words32.w2 &= 0xf8000000;
+ p_h = o.value;
+ p_l = v - (p_h - u);
+ z_h = cp_h * p_h; /* cp_h+cp_l = 2/(3*log2) */
+ z_l = cp_l * p_h + p_l * cp + dp_l[k];
+ /* log2(ax) = (s+..)*2/(3*log2) = n + dp_h + z_h + z_l */
+ t = (__float128) n;
+ t1 = (((z_h + z_l) + dp_h[k]) + t);
+ o.value = t1;
+ o.words32.w3 = 0;
+ o.words32.w2 &= 0xf8000000;
+ t1 = o.value;
+ t2 = z_l - (((t1 - t) - dp_h[k]) - z_h);
+
+ /* s (sign of result -ve**odd) = -1 else = 1 */
+ s = one;
+ if (((((uint32_t) hx >> 31) - 1) | (yisint - 1)) == 0)
+ s = -one; /* (-ve)**(odd int) */
+
+ /* split up y into y1+y2 and compute (y1+y2)*(t1+t2) */
+ y1 = y;
+ o.value = y1;
+ o.words32.w3 = 0;
+ o.words32.w2 &= 0xf8000000;
+ y1 = o.value;
+ p_l = (y - y1) * t1 + y * t2;
+ p_h = y1 * t1;
+ z = p_l + p_h;
+ o.value = z;
+ j = o.words32.w0;
+ if (j >= 0x400d0000) /* z >= 16384 */
+ {
+ /* if z > 16384 */
+ if (((j - 0x400d0000) | o.words32.w1 | o.words32.w2 | o.words32.w3) != 0)
+ return s * huge * huge; /* overflow */
+ else
+ {
+ if (p_l + ovt > z - p_h)
+ return s * huge * huge; /* overflow */
+ }
+ }
+ else if ((j & 0x7fffffff) >= 0x400d01b9) /* z <= -16495 */
+ {
+ /* z < -16495 */
+ if (((j - 0xc00d01bc) | o.words32.w1 | o.words32.w2 | o.words32.w3)
+ != 0)
+ return s * tiny * tiny; /* underflow */
+ else
+ {
+ if (p_l <= z - p_h)
+ return s * tiny * tiny; /* underflow */
+ }
+ }
+ /* compute 2**(p_h+p_l) */
+ i = j & 0x7fffffff;
+ k = (i >> 16) - 0x3fff;
+ n = 0;
+ if (i > 0x3ffe0000)
+ { /* if |z| > 0.5, set n = [z+0.5] */
+ n = floorq (z + 0.5Q);
+ t = n;
+ p_h -= t;
+ }
+ t = p_l + p_h;
+ o.value = t;
+ o.words32.w3 = 0;
+ o.words32.w2 &= 0xf8000000;
+ t = o.value;
+ u = t * lg2_h;
+ v = (p_l - (t - p_h)) * lg2 + t * lg2_l;
+ z = u + v;
+ w = v - (z - u);
+ /* exp(z) */
+ t = z * z;
+ u = PN[0] + t * (PN[1] + t * (PN[2] + t * (PN[3] + t * PN[4])));
+ v = PD[0] + t * (PD[1] + t * (PD[2] + t * (PD[3] + t)));
+ t1 = z - t * u / v;
+ r = (z * t1) / (t1 - two) - (w + z * w);
+ z = one - (r - z);
+ o.value = z;
+ j = o.words32.w0;
+ j += (n << 16);
+ if ((j >> 16) <= 0)
+ z = scalbnq (z, n); /* subnormal output */
+ else
+ {
+ o.words32.w0 = j;
+ z = o.value;
+ }
+ return s * z;
+}
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