/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2011 Nexenta Systems, Inc. All rights reserved. */ /* * Copyright 2006 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ #pragma weak fmal = __fmal #include "libm.h" #include "fma.h" #include "fenv_inlines.h" #if defined(__sparc) static const union { unsigned i[2]; double d; } C[] = { { 0x3fe00000u, 0 }, { 0x40000000u, 0 }, { 0x3ef00000u, 0 }, { 0x3e700000u, 0 }, { 0x41300000u, 0 }, { 0x3e300000u, 0 }, { 0x3b300000u, 0 }, { 0x38300000u, 0 }, { 0x42300000u, 0 }, { 0x3df00000u, 0 }, { 0x7fe00000u, 0 }, { 0x00100000u, 0 }, { 0x00100001u, 0 }, { 0, 0 }, { 0x7ff00000u, 0 }, { 0x7ff00001u, 0 } }; #define half C[0].d #define two C[1].d #define twom16 C[2].d #define twom24 C[3].d #define two20 C[4].d #define twom28 C[5].d #define twom76 C[6].d #define twom124 C[7].d #define two36 C[8].d #define twom32 C[9].d #define huge C[10].d #define tiny C[11].d #define tiny2 C[12].d #define zero C[13].d #define inf C[14].d #define snan C[15].d static const unsigned int fsr_rm = 0xc0000000u; /* * fmal for SPARC: 128-bit quad precision, big-endian */ long double __fmal(long double x, long double y, long double z) { union { unsigned int i[4]; long double q; } xx, yy, zz; union { unsigned int i[2]; double d; } u; double dx[5], dy[5], dxy[9], c, s; unsigned int xy0, xy1, xy2, xy3, xy4, xy5, xy6, xy7; unsigned int z0, z1, z2, z3, z4, z5, z6, z7; unsigned int rm, sticky; unsigned int fsr; int hx, hy, hz, ex, ey, ez, exy, sxy, sz, e, ibit; int cx, cy, cz; volatile double dummy; /* extract the high order words of the arguments */ xx.q = x; yy.q = y; zz.q = z; hx = xx.i[0] & ~0x80000000; hy = yy.i[0] & ~0x80000000; hz = zz.i[0] & ~0x80000000; /* * distinguish zero, finite nonzero, infinite, and quiet nan * arguments; raise invalid and return for signaling nans */ if (hx >= 0x7fff0000) { if ((hx & 0xffff) | xx.i[1] | xx.i[2] | xx.i[3]) { if (!(hx & 0x8000)) { /* signaling nan, raise invalid */ dummy = snan; dummy += snan; xx.i[0] |= 0x8000; return (xx.q); } cx = 3; /* quiet nan */ } else cx = 2; /* inf */ } else if (hx == 0) { cx = (xx.i[1] | xx.i[2] | xx.i[3]) ? 1 : 0; /* subnormal or zero */ } else cx = 1; /* finite nonzero */ if (hy >= 0x7fff0000) { if ((hy & 0xffff) | yy.i[1] | yy.i[2] | yy.i[3]) { if (!(hy & 0x8000)) { dummy = snan; dummy += snan; yy.i[0] |= 0x8000; return (yy.q); } cy = 3; } else cy = 2; } else if (hy == 0) { cy = (yy.i[1] | yy.i[2] | yy.i[3]) ? 1 : 0; } else cy = 1; if (hz >= 0x7fff0000) { if ((hz & 0xffff) | zz.i[1] | zz.i[2] | zz.i[3]) { if (!(hz & 0x8000)) { dummy = snan; dummy += snan; zz.i[0] |= 0x8000; return (zz.q); } cz = 3; } else cz = 2; } else if (hz == 0) { cz = (zz.i[1] | zz.i[2] | zz.i[3]) ? 1 : 0; } else cz = 1; /* get the fsr and clear current exceptions */ __fenv_getfsr32(&fsr); fsr &= ~FSR_CEXC; /* handle all other zero, inf, and nan cases */ if (cx != 1 || cy != 1 || cz != 1) { /* if x or y is a quiet nan, return it */ if (cx == 3) { __fenv_setfsr32(&fsr); return (x); } if (cy == 3) { __fenv_setfsr32(&fsr); return (y); } /* if x*y is 0*inf, raise invalid and return the default nan */ if ((cx == 0 && cy == 2) || (cx == 2 && cy == 0)) { dummy = zero; dummy *= inf; zz.i[0] = 0x7fffffff; zz.i[1] = zz.i[2] = zz.i[3] = 0xffffffff; return (zz.q); } /* if z is a quiet nan, return it */ if (cz == 3) { __fenv_setfsr32(&fsr); return (z); } /* * now none of x, y, or z is nan; handle cases where x or y * is inf */ if (cx == 2 || cy == 2) { /* * if z is also inf, either we have inf-inf or * the result is the same as z depending on signs */ if (cz == 2) { if ((int) ((xx.i[0] ^ yy.i[0]) ^ zz.i[0]) < 0) { dummy = inf; dummy -= inf; zz.i[0] = 0x7fffffff; zz.i[1] = zz.i[2] = zz.i[3] = 0xffffffff; return (zz.q); } __fenv_setfsr32(&fsr); return (z); } /* otherwise the result is inf with appropriate sign */ zz.i[0] = ((xx.i[0] ^ yy.i[0]) & 0x80000000) | 0x7fff0000; zz.i[1] = zz.i[2] = zz.i[3] = 0; __fenv_setfsr32(&fsr); return (zz.q); } /* if z is inf, return it */ if (cz == 2) { __fenv_setfsr32(&fsr); return (z); } /* * now x, y, and z are all finite; handle cases where x or y * is zero */ if (cx == 0 || cy == 0) { /* either we have 0-0 or the result is the same as z */ if (cz == 0 && (int) ((xx.i[0] ^ yy.i[0]) ^ zz.i[0]) < 0) { zz.i[0] = (fsr >> 30) == FSR_RM ? 0x80000000 : 0; __fenv_setfsr32(&fsr); return (zz.q); } __fenv_setfsr32(&fsr); return (z); } /* if we get here, x and y are nonzero finite, z must be zero */ return (x * y); } /* * now x, y, and z are all finite and nonzero; set round-to- * negative-infinity mode */ __fenv_setfsr32(&fsr_rm); /* * get the signs and exponents and normalize the significands * of x and y */ sxy = (xx.i[0] ^ yy.i[0]) & 0x80000000; ex = hx >> 16; hx &= 0xffff; if (!ex) { if (hx | (xx.i[1] & 0xfffe0000)) { ex = 1; } else if (xx.i[1] | (xx.i[2] & 0xfffe0000)) { hx = xx.i[1]; xx.i[1] = xx.i[2]; xx.i[2] = xx.i[3]; xx.i[3] = 0; ex = -31; } else if (xx.i[2] | (xx.i[3] & 0xfffe0000)) { hx = xx.i[2]; xx.i[1] = xx.i[3]; xx.i[2] = xx.i[3] = 0; ex = -63; } else { hx = xx.i[3]; xx.i[1] = xx.i[2] = xx.i[3] = 0; ex = -95; } while ((hx & 0x10000) == 0) { hx = (hx << 1) | (xx.i[1] >> 31); xx.i[1] = (xx.i[1] << 1) | (xx.i[2] >> 31); xx.i[2] = (xx.i[2] << 1) | (xx.i[3] >> 31); xx.i[3] <<= 1; ex--; } } else hx |= 0x10000; ey = hy >> 16; hy &= 0xffff; if (!ey) { if (hy | (yy.i[1] & 0xfffe0000)) { ey = 1; } else if (yy.i[1] | (yy.i[2] & 0xfffe0000)) { hy = yy.i[1]; yy.i[1] = yy.i[2]; yy.i[2] = yy.i[3]; yy.i[3] = 0; ey = -31; } else if (yy.i[2] | (yy.i[3] & 0xfffe0000)) { hy = yy.i[2]; yy.i[1] = yy.i[3]; yy.i[2] = yy.i[3] = 0; ey = -63; } else { hy = yy.i[3]; yy.i[1] = yy.i[2] = yy.i[3] = 0; ey = -95; } while ((hy & 0x10000) == 0) { hy = (hy << 1) | (yy.i[1] >> 31); yy.i[1] = (yy.i[1] << 1) | (yy.i[2] >> 31); yy.i[2] = (yy.i[2] << 1) | (yy.i[3] >> 31); yy.i[3] <<= 1; ey--; } } else hy |= 0x10000; exy = ex + ey - 0x3fff; /* convert the significands of x and y to doubles */ c = twom16; dx[0] = (double) ((int) hx) * c; dy[0] = (double) ((int) hy) * c; c *= twom24; dx[1] = (double) ((int) (xx.i[1] >> 8)) * c; dy[1] = (double) ((int) (yy.i[1] >> 8)) * c; c *= twom24; dx[2] = (double) ((int) (((xx.i[1] << 16) | (xx.i[2] >> 16)) & 0xffffff)) * c; dy[2] = (double) ((int) (((yy.i[1] << 16) | (yy.i[2] >> 16)) & 0xffffff)) * c; c *= twom24; dx[3] = (double) ((int) (((xx.i[2] << 8) | (xx.i[3] >> 24)) & 0xffffff)) * c; dy[3] = (double) ((int) (((yy.i[2] << 8) | (yy.i[3] >> 24)) & 0xffffff)) * c; c *= twom24; dx[4] = (double) ((int) (xx.i[3] & 0xffffff)) * c; dy[4] = (double) ((int) (yy.i[3] & 0xffffff)) * c; /* form the "digits" of the product */ dxy[0] = dx[0] * dy[0]; dxy[1] = dx[0] * dy[1] + dx[1] * dy[0]; dxy[2] = dx[0] * dy[2] + dx[1] * dy[1] + dx[2] * dy[0]; dxy[3] = dx[0] * dy[3] + dx[1] * dy[2] + dx[2] * dy[1] + dx[3] * dy[0]; dxy[4] = dx[0] * dy[4] + dx[1] * dy[3] + dx[2] * dy[2] + dx[3] * dy[1] + dx[4] * dy[0]; dxy[5] = dx[1] * dy[4] + dx[2] * dy[3] + dx[3] * dy[2] + dx[4] * dy[1]; dxy[6] = dx[2] * dy[4] + dx[3] * dy[3] + dx[4] * dy[2]; dxy[7] = dx[3] * dy[4] + dx[4] * dy[3]; dxy[8] = dx[4] * dy[4]; /* split odd-numbered terms and combine into even-numbered terms */ c = (dxy[1] + two20) - two20; dxy[0] += c; dxy[1] -= c; c = (dxy[3] + twom28) - twom28; dxy[2] += c + dxy[1]; dxy[3] -= c; c = (dxy[5] + twom76) - twom76; dxy[4] += c + dxy[3]; dxy[5] -= c; c = (dxy[7] + twom124) - twom124; dxy[6] += c + dxy[5]; dxy[8] += (dxy[7] - c); /* propagate carries, adjusting the exponent if need be */ dxy[7] = dxy[6] + dxy[8]; dxy[5] = dxy[4] + dxy[7]; dxy[3] = dxy[2] + dxy[5]; dxy[1] = dxy[0] + dxy[3]; if (dxy[1] >= two) { dxy[0] *= half; dxy[1] *= half; dxy[2] *= half; dxy[3] *= half; dxy[4] *= half; dxy[5] *= half; dxy[6] *= half; dxy[7] *= half; dxy[8] *= half; exy++; } /* extract the significand of x*y */ s = two36; u.d = c = dxy[1] + s; xy0 = u.i[1]; c -= s; dxy[1] -= c; dxy[0] -= c; s *= twom32; u.d = c = dxy[1] + s; xy1 = u.i[1]; c -= s; dxy[2] += (dxy[0] - c); dxy[3] = dxy[2] + dxy[5]; s *= twom32; u.d = c = dxy[3] + s; xy2 = u.i[1]; c -= s; dxy[4] += (dxy[2] - c); dxy[5] = dxy[4] + dxy[7]; s *= twom32; u.d = c = dxy[5] + s; xy3 = u.i[1]; c -= s; dxy[4] -= c; dxy[5] = dxy[4] + dxy[7]; s *= twom32; u.d = c = dxy[5] + s; xy4 = u.i[1]; c -= s; dxy[6] += (dxy[4] - c); dxy[7] = dxy[6] + dxy[8]; s *= twom32; u.d = c = dxy[7] + s; xy5 = u.i[1]; c -= s; dxy[8] += (dxy[6] - c); s *= twom32; u.d = c = dxy[8] + s; xy6 = u.i[1]; c -= s; dxy[8] -= c; s *= twom32; u.d = c = dxy[8] + s; xy7 = u.i[1]; /* extract the sign, exponent, and significand of z */ sz = zz.i[0] & 0x80000000; ez = hz >> 16; z0 = hz & 0xffff; if (!ez) { if (z0 | (zz.i[1] & 0xfffe0000)) { z1 = zz.i[1]; z2 = zz.i[2]; z3 = zz.i[3]; ez = 1; } else if (zz.i[1] | (zz.i[2] & 0xfffe0000)) { z0 = zz.i[1]; z1 = zz.i[2]; z2 = zz.i[3]; z3 = 0; ez = -31; } else if (zz.i[2] | (zz.i[3] & 0xfffe0000)) { z0 = zz.i[2]; z1 = zz.i[3]; z2 = z3 = 0; ez = -63; } else { z0 = zz.i[3]; z1 = z2 = z3 = 0; ez = -95; } while ((z0 & 0x10000) == 0) { z0 = (z0 << 1) | (z1 >> 31); z1 = (z1 << 1) | (z2 >> 31); z2 = (z2 << 1) | (z3 >> 31); z3 <<= 1; ez--; } } else { z0 |= 0x10000; z1 = zz.i[1]; z2 = zz.i[2]; z3 = zz.i[3]; } z4 = z5 = z6 = z7 = 0; /* * now x*y is represented by sxy, exy, and xy[0-7], and z is * represented likewise; swap if need be so |xy| <= |z| */ if (exy > ez || (exy == ez && (xy0 > z0 || (xy0 == z0 && (xy1 > z1 || (xy1 == z1 && (xy2 > z2 || (xy2 == z2 && (xy3 > z3 || (xy3 == z3 && (xy4 | xy5 | xy6 | xy7) != 0)))))))))) { e = sxy; sxy = sz; sz = e; e = exy; exy = ez; ez = e; e = xy0; xy0 = z0; z0 = e; e = xy1; xy1 = z1; z1 = e; e = xy2; xy2 = z2; z2 = e; e = xy3; xy3 = z3; z3 = e; z4 = xy4; xy4 = 0; z5 = xy5; xy5 = 0; z6 = xy6; xy6 = 0; z7 = xy7; xy7 = 0; } /* shift the significand of xy keeping a sticky bit */ e = ez - exy; if (e > 236) { xy0 = xy1 = xy2 = xy3 = xy4 = xy5 = xy6 = 0; xy7 = 1; } else if (e >= 224) { sticky = xy7 | xy6 | xy5 | xy4 | xy3 | xy2 | xy1 | ((xy0 << 1) << (255 - e)); xy7 = xy0 >> (e - 224); if (sticky) xy7 |= 1; xy0 = xy1 = xy2 = xy3 = xy4 = xy5 = xy6 = 0; } else if (e >= 192) { sticky = xy7 | xy6 | xy5 | xy4 | xy3 | xy2 | ((xy1 << 1) << (223 - e)); xy7 = (xy1 >> (e - 192)) | ((xy0 << 1) << (223 - e)); if (sticky) xy7 |= 1; xy6 = xy0 >> (e - 192); xy0 = xy1 = xy2 = xy3 = xy4 = xy5 = 0; } else if (e >= 160) { sticky = xy7 | xy6 | xy5 | xy4 | xy3 | ((xy2 << 1) << (191 - e)); xy7 = (xy2 >> (e - 160)) | ((xy1 << 1) << (191 - e)); if (sticky) xy7 |= 1; xy6 = (xy1 >> (e - 160)) | ((xy0 << 1) << (191 - e)); xy5 = xy0 >> (e - 160); xy0 = xy1 = xy2 = xy3 = xy4 = 0; } else if (e >= 128) { sticky = xy7 | xy6 | xy5 | xy4 | ((xy3 << 1) << (159 - e)); xy7 = (xy3 >> (e - 128)) | ((xy2 << 1) << (159 - e)); if (sticky) xy7 |= 1; xy6 = (xy2 >> (e - 128)) | ((xy1 << 1) << (159 - e)); xy5 = (xy1 >> (e - 128)) | ((xy0 << 1) << (159 - e)); xy4 = xy0 >> (e - 128); xy0 = xy1 = xy2 = xy3 = 0; } else if (e >= 96) { sticky = xy7 | xy6 | xy5 | ((xy4 << 1) << (127 - e)); xy7 = (xy4 >> (e - 96)) | ((xy3 << 1) << (127 - e)); if (sticky) xy7 |= 1; xy6 = (xy3 >> (e - 96)) | ((xy2 << 1) << (127 - e)); xy5 = (xy2 >> (e - 96)) | ((xy1 << 1) << (127 - e)); xy4 = (xy1 >> (e - 96)) | ((xy0 << 1) << (127 - e)); xy3 = xy0 >> (e - 96); xy0 = xy1 = xy2 = 0; } else if (e >= 64) { sticky = xy7 | xy6 | ((xy5 << 1) << (95 - e)); xy7 = (xy5 >> (e - 64)) | ((xy4 << 1) << (95 - e)); if (sticky) xy7 |= 1; xy6 = (xy4 >> (e - 64)) | ((xy3 << 1) << (95 - e)); xy5 = (xy3 >> (e - 64)) | ((xy2 << 1) << (95 - e)); xy4 = (xy2 >> (e - 64)) | ((xy1 << 1) << (95 - e)); xy3 = (xy1 >> (e - 64)) | ((xy0 << 1) << (95 - e)); xy2 = xy0 >> (e - 64); xy0 = xy1 = 0; } else if (e >= 32) { sticky = xy7 | ((xy6 << 1) << (63 - e)); xy7 = (xy6 >> (e - 32)) | ((xy5 << 1) << (63 - e)); if (sticky) xy7 |= 1; xy6 = (xy5 >> (e - 32)) | ((xy4 << 1) << (63 - e)); xy5 = (xy4 >> (e - 32)) | ((xy3 << 1) << (63 - e)); xy4 = (xy3 >> (e - 32)) | ((xy2 << 1) << (63 - e)); xy3 = (xy2 >> (e - 32)) | ((xy1 << 1) << (63 - e)); xy2 = (xy1 >> (e - 32)) | ((xy0 << 1) << (63 - e)); xy1 = xy0 >> (e - 32); xy0 = 0; } else if (e) { sticky = (xy7 << 1) << (31 - e); xy7 = (xy7 >> e) | ((xy6 << 1) << (31 - e)); if (sticky) xy7 |= 1; xy6 = (xy6 >> e) | ((xy5 << 1) << (31 - e)); xy5 = (xy5 >> e) | ((xy4 << 1) << (31 - e)); xy4 = (xy4 >> e) | ((xy3 << 1) << (31 - e)); xy3 = (xy3 >> e) | ((xy2 << 1) << (31 - e)); xy2 = (xy2 >> e) | ((xy1 << 1) << (31 - e)); xy1 = (xy1 >> e) | ((xy0 << 1) << (31 - e)); xy0 >>= e; } /* if this is a magnitude subtract, negate the significand of xy */ if (sxy ^ sz) { xy0 = ~xy0; xy1 = ~xy1; xy2 = ~xy2; xy3 = ~xy3; xy4 = ~xy4; xy5 = ~xy5; xy6 = ~xy6; xy7 = -xy7; if (xy7 == 0) if (++xy6 == 0) if (++xy5 == 0) if (++xy4 == 0) if (++xy3 == 0) if (++xy2 == 0) if (++xy1 == 0) xy0++; } /* add, propagating carries */ z7 += xy7; e = (z7 < xy7); z6 += xy6; if (e) { z6++; e = (z6 <= xy6); } else e = (z6 < xy6); z5 += xy5; if (e) { z5++; e = (z5 <= xy5); } else e = (z5 < xy5); z4 += xy4; if (e) { z4++; e = (z4 <= xy4); } else e = (z4 < xy4); z3 += xy3; if (e) { z3++; e = (z3 <= xy3); } else e = (z3 < xy3); z2 += xy2; if (e) { z2++; e = (z2 <= xy2); } else e = (z2 < xy2); z1 += xy1; if (e) { z1++; e = (z1 <= xy1); } else e = (z1 < xy1); z0 += xy0; if (e) z0++; /* postnormalize and collect rounding information into z4 */ if (ez < 1) { /* result is tiny; shift right until exponent is within range */ e = 1 - ez; if (e > 116) { z4 = 1; /* result can't be exactly zero */ z0 = z1 = z2 = z3 = 0; } else if (e >= 96) { sticky = z7 | z6 | z5 | z4 | z3 | z2 | ((z1 << 1) << (127 - e)); z4 = (z1 >> (e - 96)) | ((z0 << 1) << (127 - e)); if (sticky) z4 |= 1; z3 = z0 >> (e - 96); z0 = z1 = z2 = 0; } else if (e >= 64) { sticky = z7 | z6 | z5 | z4 | z3 | ((z2 << 1) << (95 - e)); z4 = (z2 >> (e - 64)) | ((z1 << 1) << (95 - e)); if (sticky) z4 |= 1; z3 = (z1 >> (e - 64)) | ((z0 << 1) << (95 - e)); z2 = z0 >> (e - 64); z0 = z1 = 0; } else if (e >= 32) { sticky = z7 | z6 | z5 | z4 | ((z3 << 1) << (63 - e)); z4 = (z3 >> (e - 32)) | ((z2 << 1) << (63 - e)); if (sticky) z4 |= 1; z3 = (z2 >> (e - 32)) | ((z1 << 1) << (63 - e)); z2 = (z1 >> (e - 32)) | ((z0 << 1) << (63 - e)); z1 = z0 >> (e - 32); z0 = 0; } else { sticky = z7 | z6 | z5 | (z4 << 1) << (31 - e); z4 = (z4 >> e) | ((z3 << 1) << (31 - e)); if (sticky) z4 |= 1; z3 = (z3 >> e) | ((z2 << 1) << (31 - e)); z2 = (z2 >> e) | ((z1 << 1) << (31 - e)); z1 = (z1 >> e) | ((z0 << 1) << (31 - e)); z0 >>= e; } ez = 1; } else if (z0 >= 0x20000) { /* carry out; shift right by one */ sticky = (z4 & 1) | z5 | z6 | z7; z4 = (z4 >> 1) | (z3 << 31); if (sticky) z4 |= 1; z3 = (z3 >> 1) | (z2 << 31); z2 = (z2 >> 1) | (z1 << 31); z1 = (z1 >> 1) | (z0 << 31); z0 >>= 1; ez++; } else { if (z0 < 0x10000 && (z0 | z1 | z2 | z3 | z4 | z5 | z6 | z7) != 0) { /* * borrow/cancellation; shift left as much as * exponent allows */ while (!(z0 | (z1 & 0xfffe0000)) && ez >= 33) { z0 = z1; z1 = z2; z2 = z3; z3 = z4; z4 = z5; z5 = z6; z6 = z7; z7 = 0; ez -= 32; } while (z0 < 0x10000 && ez > 1) { z0 = (z0 << 1) | (z1 >> 31); z1 = (z1 << 1) | (z2 >> 31); z2 = (z2 << 1) | (z3 >> 31); z3 = (z3 << 1) | (z4 >> 31); z4 = (z4 << 1) | (z5 >> 31); z5 = (z5 << 1) | (z6 >> 31); z6 = (z6 << 1) | (z7 >> 31); z7 <<= 1; ez--; } } if (z5 | z6 | z7) z4 |= 1; } /* get the rounding mode */ rm = fsr >> 30; /* strip off the integer bit, if there is one */ ibit = z0 & 0x10000; if (ibit) z0 -= 0x10000; else { ez = 0; if (!(z0 | z1 | z2 | z3 | z4)) { /* exact zero */ zz.i[0] = rm == FSR_RM ? 0x80000000 : 0; zz.i[1] = zz.i[2] = zz.i[3] = 0; __fenv_setfsr32(&fsr); return (zz.q); } } /* * flip the sense of directed roundings if the result is negative; * the logic below applies to a positive result */ if (sz) rm ^= rm >> 1; /* round and raise exceptions */ if (z4) { fsr |= FSR_NXC; /* decide whether to round the fraction up */ if (rm == FSR_RP || (rm == FSR_RN && (z4 > 0x80000000u || (z4 == 0x80000000u && (z3 & 1))))) { /* round up and renormalize if necessary */ if (++z3 == 0) if (++z2 == 0) if (++z1 == 0) if (++z0 == 0x10000) { z0 = 0; ez++; } } } /* check for under/overflow */ if (ez >= 0x7fff) { if (rm == FSR_RN || rm == FSR_RP) { zz.i[0] = sz | 0x7fff0000; zz.i[1] = zz.i[2] = zz.i[3] = 0; } else { zz.i[0] = sz | 0x7ffeffff; zz.i[1] = zz.i[2] = zz.i[3] = 0xffffffff; } fsr |= FSR_OFC | FSR_NXC; } else { zz.i[0] = sz | (ez << 16) | z0; zz.i[1] = z1; zz.i[2] = z2; zz.i[3] = z3; /* * !ibit => exact result was tiny before rounding, * z4 nonzero => result delivered is inexact */ if (!ibit) { if (z4) fsr |= FSR_UFC | FSR_NXC; else if (fsr & FSR_UFM) fsr |= FSR_UFC; } } /* restore the fsr and emulate exceptions as needed */ if ((fsr & FSR_CEXC) & (fsr >> 23)) { __fenv_setfsr32(&fsr); if (fsr & FSR_OFC) { dummy = huge; dummy *= huge; } else if (fsr & FSR_UFC) { dummy = tiny; if (fsr & FSR_NXC) dummy *= tiny; else dummy -= tiny2; } else { dummy = huge; dummy += tiny; } } else { fsr |= (fsr & 0x1f) << 5; __fenv_setfsr32(&fsr); } return (zz.q); } #elif defined(__x86) static const union { unsigned i[2]; double d; } C[] = { { 0, 0x3fe00000u }, { 0, 0x40000000u }, { 0, 0x3df00000u }, { 0, 0x3bf00000u }, { 0, 0x41f00000u }, { 0, 0x43e00000u }, { 0, 0x7fe00000u }, { 0, 0x00100000u }, { 0, 0x00100001u } }; #define half C[0].d #define two C[1].d #define twom32 C[2].d #define twom64 C[3].d #define two32 C[4].d #define two63 C[5].d #define huge C[6].d #define tiny C[7].d #define tiny2 C[8].d #if defined(__amd64) #define NI 4 #else #define NI 3 #endif /* * fmal for x86: 80-bit extended double precision, little-endian */ long double __fmal(long double x, long double y, long double z) { union { unsigned i[NI]; long double e; } xx, yy, zz; long double xhi, yhi, xlo, ylo, t; unsigned xy0, xy1, xy2, xy3, xy4, z0, z1, z2, z3, z4; unsigned oldcwsw, cwsw, rm, sticky, carry; int ex, ey, ez, exy, sxy, sz, e, tinyafter; volatile double dummy; /* extract the exponents of the arguments */ xx.e = x; yy.e = y; zz.e = z; ex = xx.i[2] & 0x7fff; ey = yy.i[2] & 0x7fff; ez = zz.i[2] & 0x7fff; /* dispense with inf, nan, and zero cases */ if (ex == 0x7fff || ey == 0x7fff || (ex | xx.i[1] | xx.i[0]) == 0 || (ey | yy.i[1] | yy.i[0]) == 0) /* x or y is inf, nan, or 0 */ return (x * y + z); if (ez == 0x7fff) /* z is inf or nan */ return (x + z); /* avoid spurious under/overflow in x * y */ if ((ez | zz.i[1] | zz.i[0]) == 0) /* z is zero */ /* * x * y isn't zero but could underflow to zero, * so don't add z, lest we perturb the sign */ return (x * y); /* * now x, y, and z are all finite and nonzero; extract signs and * normalize the significands (this will raise the denormal operand * exception if need be) */ sxy = (xx.i[2] ^ yy.i[2]) & 0x8000; sz = zz.i[2] & 0x8000; if (!ex) { xx.e = x * two63; ex = (xx.i[2] & 0x7fff) - 63; } if (!ey) { yy.e = y * two63; ey = (yy.i[2] & 0x7fff) - 63; } if (!ez) { zz.e = z * two63; ez = (zz.i[2] & 0x7fff) - 63; } /* * save the control and status words, mask all exceptions, and * set rounding to 64-bit precision and toward-zero */ __fenv_getcwsw(&oldcwsw); cwsw = (oldcwsw & 0xf0c0ffff) | 0x0f3f0000; __fenv_setcwsw(&cwsw); /* multiply x*y to 128 bits */ exy = ex + ey - 0x3fff; xx.i[2] = 0x3fff; yy.i[2] = 0x3fff; x = xx.e; y = yy.e; xhi = ((x + twom32) + two32) - two32; yhi = ((y + twom32) + two32) - two32; xlo = x - xhi; ylo = y - yhi; x *= y; y = ((xhi * yhi - x) + xhi * ylo + xlo * yhi) + xlo * ylo; if (x >= two) { x *= half; y *= half; exy++; } /* extract the significands */ xx.e = x; xy0 = xx.i[1]; xy1 = xx.i[0]; yy.e = t = y + twom32; xy2 = yy.i[0]; yy.e = (y - (t - twom32)) + twom64; xy3 = yy.i[0]; xy4 = 0; z0 = zz.i[1]; z1 = zz.i[0]; z2 = z3 = z4 = 0; /* * now x*y is represented by sxy, exy, and xy[0-4], and z is * represented likewise; swap if need be so |xy| <= |z| */ if (exy > ez || (exy == ez && (xy0 > z0 || (xy0 == z0 && (xy1 > z1 || (xy1 == z1 && (xy2 | xy3) != 0)))))) { e = sxy; sxy = sz; sz = e; e = exy; exy = ez; ez = e; e = xy0; xy0 = z0; z0 = e; e = xy1; xy1 = z1; z1 = e; z2 = xy2; xy2 = 0; z3 = xy3; xy3 = 0; } /* shift the significand of xy keeping a sticky bit */ e = ez - exy; if (e > 130) { xy0 = xy1 = xy2 = xy3 = 0; xy4 = 1; } else if (e >= 128) { sticky = xy3 | xy2 | xy1 | ((xy0 << 1) << (159 - e)); xy4 = xy0 >> (e - 128); if (sticky) xy4 |= 1; xy0 = xy1 = xy2 = xy3 = 0; } else if (e >= 96) { sticky = xy3 | xy2 | ((xy1 << 1) << (127 - e)); xy4 = (xy1 >> (e - 96)) | ((xy0 << 1) << (127 - e)); if (sticky) xy4 |= 1; xy3 = xy0 >> (e - 96); xy0 = xy1 = xy2 = 0; } else if (e >= 64) { sticky = xy3 | ((xy2 << 1) << (95 - e)); xy4 = (xy2 >> (e - 64)) | ((xy1 << 1) << (95 - e)); if (sticky) xy4 |= 1; xy3 = (xy1 >> (e - 64)) | ((xy0 << 1) << (95 - e)); xy2 = xy0 >> (e - 64); xy0 = xy1 = 0; } else if (e >= 32) { sticky = (xy3 << 1) << (63 - e); xy4 = (xy3 >> (e - 32)) | ((xy2 << 1) << (63 - e)); if (sticky) xy4 |= 1; xy3 = (xy2 >> (e - 32)) | ((xy1 << 1) << (63 - e)); xy2 = (xy1 >> (e - 32)) | ((xy0 << 1) << (63 - e)); xy1 = xy0 >> (e - 32); xy0 = 0; } else if (e) { xy4 = (xy3 << 1) << (31 - e); xy3 = (xy3 >> e) | ((xy2 << 1) << (31 - e)); xy2 = (xy2 >> e) | ((xy1 << 1) << (31 - e)); xy1 = (xy1 >> e) | ((xy0 << 1) << (31 - e)); xy0 >>= e; } /* if this is a magnitude subtract, negate the significand of xy */ if (sxy ^ sz) { xy0 = ~xy0; xy1 = ~xy1; xy2 = ~xy2; xy3 = ~xy3; xy4 = -xy4; if (xy4 == 0) if (++xy3 == 0) if (++xy2 == 0) if (++xy1 == 0) xy0++; } /* add, propagating carries */ z4 += xy4; carry = (z4 < xy4); z3 += xy3; if (carry) { z3++; carry = (z3 <= xy3); } else carry = (z3 < xy3); z2 += xy2; if (carry) { z2++; carry = (z2 <= xy2); } else carry = (z2 < xy2); z1 += xy1; if (carry) { z1++; carry = (z1 <= xy1); } else carry = (z1 < xy1); z0 += xy0; if (carry) { z0++; carry = (z0 <= xy0); } else carry = (z0 < xy0); /* for a magnitude subtract, ignore the last carry out */ if (sxy ^ sz) carry = 0; /* postnormalize and collect rounding information into z2 */ if (ez < 1) { /* result is tiny; shift right until exponent is within range */ e = 1 - ez; if (e > 67) { z2 = 1; /* result can't be exactly zero */ z0 = z1 = 0; } else if (e >= 64) { sticky = z4 | z3 | z2 | z1 | ((z0 << 1) << (95 - e)); z2 = (z0 >> (e - 64)) | ((carry << 1) << (95 - e)); if (sticky) z2 |= 1; z1 = carry >> (e - 64); z0 = 0; } else if (e >= 32) { sticky = z4 | z3 | z2 | ((z1 << 1) << (63 - e)); z2 = (z1 >> (e - 32)) | ((z0 << 1) << (63 - e)); if (sticky) z2 |= 1; z1 = (z0 >> (e - 32)) | ((carry << 1) << (63 - e)); z0 = carry >> (e - 32); } else { sticky = z4 | z3 | (z2 << 1) << (31 - e); z2 = (z2 >> e) | ((z1 << 1) << (31 - e)); if (sticky) z2 |= 1; z1 = (z1 >> e) | ((z0 << 1) << (31 - e)); z0 = (z0 >> e) | ((carry << 1) << (31 - e)); } ez = 1; } else if (carry) { /* carry out; shift right by one */ sticky = (z2 & 1) | z3 | z4; z2 = (z2 >> 1) | (z1 << 31); if (sticky) z2 |= 1; z1 = (z1 >> 1) | (z0 << 31); z0 = (z0 >> 1) | 0x80000000; ez++; } else { if (z0 < 0x80000000u && (z0 | z1 | z2 | z3 | z4) != 0) { /* * borrow/cancellation; shift left as much as * exponent allows */ while (!z0 && ez >= 33) { z0 = z1; z1 = z2; z2 = z3; z3 = z4; z4 = 0; ez -= 32; } while (z0 < 0x80000000u && ez > 1) { z0 = (z0 << 1) | (z1 >> 31); z1 = (z1 << 1) | (z2 >> 31); z2 = (z2 << 1) | (z3 >> 31); z3 = (z3 << 1) | (z4 >> 31); z4 <<= 1; ez--; } } if (z3 | z4) z2 |= 1; } /* get the rounding mode */ rm = oldcwsw & 0x0c000000; /* adjust exponent if result is subnormal */ tinyafter = 0; if (!(z0 & 0x80000000)) { ez = 0; tinyafter = 1; if (!(z0 | z1 | z2)) { /* exact zero */ zz.i[2] = rm == FCW_RM ? 0x8000 : 0; zz.i[1] = zz.i[0] = 0; __fenv_setcwsw(&oldcwsw); return (zz.e); } } /* * flip the sense of directed roundings if the result is negative; * the logic below applies to a positive result */ if (sz && (rm == FCW_RM || rm == FCW_RP)) rm = (FCW_RM + FCW_RP) - rm; /* round */ if (z2) { if (rm == FCW_RP || (rm == FCW_RN && (z2 > 0x80000000u || (z2 == 0x80000000u && (z1 & 1))))) { /* round up and renormalize if necessary */ if (++z1 == 0) { if (++z0 == 0) { z0 = 0x80000000; ez++; } else if (z0 == 0x80000000) { /* rounded up to smallest normal */ ez = 1; if ((rm == FCW_RP && z2 > 0x80000000u) || (rm == FCW_RN && z2 >= 0xc0000000u)) /* * would have rounded up to * smallest normal even with * unbounded range */ tinyafter = 0; } } } } /* restore the control and status words, check for over/underflow */ __fenv_setcwsw(&oldcwsw); if (ez >= 0x7fff) { if (rm == FCW_RN || rm == FCW_RP) { zz.i[2] = sz | 0x7fff; zz.i[1] = 0x80000000; zz.i[0] = 0; } else { zz.i[2] = sz | 0x7ffe; zz.i[1] = 0xffffffff; zz.i[0] = 0xffffffff; } dummy = huge; dummy *= huge; } else { zz.i[2] = sz | ez; zz.i[1] = z0; zz.i[0] = z1; /* * tinyafter => result rounded w/ unbounded range would be tiny, * z2 nonzero => result delivered is inexact */ if (tinyafter) { dummy = tiny; if (z2) dummy *= tiny; else dummy -= tiny2; } else if (z2) { dummy = huge; dummy += tiny; } } return (zz.e); } #else #error Unknown architecture #endif