--- /dev/null
+/* Copyright (C) 2007 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 2, or (at your option) any later
+version.
+
+In addition to the permissions in the GNU General Public License, the
+Free Software Foundation gives you unlimited permission to link the
+compiled version of this file into combinations with other programs,
+and to distribute those combinations without any restriction coming
+from the use of this file. (The General Public License restrictions
+do apply in other respects; for example, they cover modification of
+the file, and distribution when not linked into a combine
+executable.)
+
+GCC 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 General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING. If not, write to the Free
+Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301, USA. */
+
+#define BID_128RES
+#include "bid_internal.h"
+
+BID128_FUNCTION_ARG2(__bid128_quantize, x, y)
+
+ UINT256 CT;
+ UINT128 CX, CY, T, CX2, CR, Stemp, res, REM_H, C2N;
+ UINT64 sign_x, sign_y, remainder_h, carry, CY64;
+ int_float tempx;
+ int exponent_x = 0, exponent_y = 0, digits_x, extra_digits, amount;
+ int expon_diff, total_digits, bin_expon_cx, rmode, status;
+
+ // unpack arguments, check for NaN or Infinity
+ if (!unpack_BID128_value (&sign_y, &exponent_y, &CY, y)) {
+ // y is Inf. or NaN
+#ifdef SET_STATUS_FLAGS
+ if ((x.w[1] & SNAN_MASK64) == SNAN_MASK64) // y is sNaN
+ __set_status_flags (pfpsf, INVALID_EXCEPTION);
+#endif
+
+ // test if y is NaN
+ if ((y.w[1] & 0x7c00000000000000ull) == 0x7c00000000000000ull) {
+#ifdef SET_STATUS_FLAGS
+ if ((y.w[1] & 0x7e00000000000000ull) == 0x7e00000000000000ull) {
+ // set status flags
+ __set_status_flags (pfpsf, INVALID_EXCEPTION);
+ }
+#endif
+ res.w[1] = y.w[1] & QUIET_MASK64;
+ res.w[0] = y.w[0];
+ BID_RETURN (res);
+ }
+ // y is Infinity?
+ if ((y.w[1] & 0x7800000000000000ull) == 0x7800000000000000ull) {
+ // check if x is not Inf.
+ if (((x.w[1] & 0x7c00000000000000ull) < 0x7800000000000000ull)) {
+ // return NaN
+#ifdef SET_STATUS_FLAGS
+ // set status flags
+ __set_status_flags (pfpsf, INVALID_EXCEPTION);
+#endif
+ res.w[1] = 0x7c00000000000000ull;
+ res.w[0] = 0;
+ BID_RETURN (res);
+ } else if (((x.w[1] & 0x7c00000000000000ull) <= 0x7800000000000000ull)) {
+ res.w[1] = x.w[1];
+ res.w[0] = x.w[0];
+ BID_RETURN (res);
+ }
+ }
+ }
+
+ if (!unpack_BID128_value (&sign_x, &exponent_x, &CX, x)) {
+ // test if x is NaN or Inf
+ if ((x.w[1] & 0x7c00000000000000ull) == 0x7800000000000000ull) {
+#ifdef SET_STATUS_FLAGS
+ // set status flags
+ __set_status_flags (pfpsf, INVALID_EXCEPTION);
+#endif
+ res.w[1] = 0x7c00000000000000ull;
+ res.w[0] = x.w[0];
+ BID_RETURN (res);
+ } else if ((x.w[1] & 0x7c00000000000000ull) ==
+ 0x7c00000000000000ull) {
+ if ((x.w[1] & 0x7e00000000000000ull) == 0x7e00000000000000ull) {
+#ifdef SET_STATUS_FLAGS
+ // set status flags
+ __set_status_flags (pfpsf, INVALID_EXCEPTION);
+#endif
+ }
+ res.w[1] = x.w[1] & QUIET_MASK64;
+ res.w[0] = x.w[0];
+ BID_RETURN (res);
+ }
+ if (!CX.w[1] && !CX.w[0]) {
+ get_BID128_very_fast (&res, sign_x, exponent_y, CX);
+ BID_RETURN (res);
+ }
+ }
+ // get number of decimal digits in coefficient_x
+ if (CX.w[1]) {
+ tempx.d = (float) CX.w[1];
+ bin_expon_cx = ((tempx.i >> 23) & 0xff) - 0x7f + 64;
+ } else {
+ tempx.d = (float) CX.w[0];
+ bin_expon_cx = ((tempx.i >> 23) & 0xff) - 0x7f;
+ }
+ digits_x = __bid_estimate_decimal_digits[bin_expon_cx];
+ if (CX.w[1] > __bid_power10_table_128[digits_x].w[1]
+ || (CX.w[1] == __bid_power10_table_128[digits_x].w[1]
+ && CX.w[0] >= __bid_power10_table_128[digits_x].w[0]))
+ digits_x++;
+
+ expon_diff = exponent_x - exponent_y;
+ total_digits = digits_x + expon_diff;
+
+ if ((UINT32) total_digits <= 34) {
+ if (expon_diff >= 0) {
+ T = __bid_power10_table_128[expon_diff];
+ __mul_128x128_low (CX2, T, CX);
+ get_BID128_very_fast (&res, sign_x, exponent_y, CX2);
+ BID_RETURN (res);
+ }
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+#ifndef IEEE_ROUND_NEAREST
+ rmode = rnd_mode;
+ if (sign_x && (unsigned) (rmode - 1) < 2)
+ rmode = 3 - rmode;
+#else
+ rmode = 0;
+#endif
+#else
+ rmode = 0;
+#endif
+ // must round off -expon_diff digits
+ extra_digits = -expon_diff;
+ __add_128_128 (CX, CX, __bid_round_const_table_128[rmode][extra_digits]);
+
+ // get P*(2^M[extra_digits])/10^extra_digits
+ __mul_128x128_to_256 (CT, CX, __bid_reciprocals10_128[extra_digits]);
+
+ // now get P/10^extra_digits: shift C64 right by M[extra_digits]-128
+ amount = __bid_recip_scale[extra_digits];
+ CX2.w[0] = CT.w[2];
+ CX2.w[1] = CT.w[3];
+ if (amount >= 64) {
+ CR.w[1] = 0;
+ CR.w[0] = CX2.w[1] >> (amount - 64);
+ } else {
+ __shr_128 (CR, CX2, amount);
+ }
+
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+#ifndef IEEE_ROUND_NEAREST
+ if (rnd_mode == 0)
+#endif
+ if (CR.w[0] & 1) {
+ // check whether fractional part of initial_P/10^extra_digits is
+ // exactly .5 this is the same as fractional part of
+ // (initial_P + 0.5*10^extra_digits)/10^extra_digits is exactly zero
+
+ // get remainder
+ if (amount >= 64) {
+ remainder_h = CX2.w[0] | (CX2.w[1] << (128 - amount));
+ } else
+ remainder_h = CX2.w[0] << (64 - amount);
+
+ // test whether fractional part is 0
+ if (!remainder_h
+ && (CT.w[1] < __bid_reciprocals10_128[extra_digits].w[1]
+ || (CT.w[1] == __bid_reciprocals10_128[extra_digits].w[1]
+ && CT.w[0] < __bid_reciprocals10_128[extra_digits].w[0]))) {
+ CR.w[0]--;
+ }
+ }
+#endif
+
+#ifdef SET_STATUS_FLAGS
+ status = INEXACT_EXCEPTION;
+
+ // get remainder
+ if (amount >= 64) {
+ REM_H.w[1] = (CX2.w[1] << (128 - amount));
+ REM_H.w[0] = CX2.w[0];
+ } else {
+ REM_H.w[1] = CX2.w[0] << (64 - amount);
+ REM_H.w[0] = 0;
+ }
+
+ switch (rmode) {
+ case ROUNDING_TO_NEAREST:
+ case ROUNDING_TIES_AWAY:
+ // test whether fractional part is 0
+ if (REM_H.w[1] == 0x8000000000000000ull && !REM_H.w[0]
+ && (CT.w[1] < __bid_reciprocals10_128[extra_digits].w[1]
+ || (CT.w[1] == __bid_reciprocals10_128[extra_digits].w[1]
+ && CT.w[0] < __bid_reciprocals10_128[extra_digits].w[0])))
+ status = EXACT_STATUS;
+ break;
+ case ROUNDING_DOWN:
+ case ROUNDING_TO_ZERO:
+ if (!(REM_H.w[1] | REM_H.w[0])
+ && (CT.w[1] < __bid_reciprocals10_128[extra_digits].w[1]
+ || (CT.w[1] == __bid_reciprocals10_128[extra_digits].w[1]
+ && CT.w[0] < __bid_reciprocals10_128[extra_digits].w[0])))
+ status = EXACT_STATUS;
+ break;
+ default:
+ // round up
+ __add_carry_out (Stemp.w[0], CY64, CT.w[0],
+ __bid_reciprocals10_128[extra_digits].w[0]);
+ __add_carry_in_out (Stemp.w[1], carry, CT.w[1],
+ __bid_reciprocals10_128[extra_digits].w[1], CY64);
+ if (amount < 64) {
+ C2N.w[1] = 0;
+ C2N.w[0] = ((UINT64) 1) << amount;
+ REM_H.w[0] = REM_H.w[1] >> (64 - amount);
+ REM_H.w[1] = 0;
+ } else {
+ C2N.w[1] = ((UINT64) 1) << (amount - 64);
+ C2N.w[0] = 0;
+ REM_H.w[1] >>= (128 - amount);
+ }
+ REM_H.w[0] += carry;
+ if (REM_H.w[0] < carry)
+ REM_H.w[1]++;
+ if (__unsigned_compare_ge_128 (REM_H, C2N))
+ status = EXACT_STATUS;
+ }
+
+ __set_status_flags (pfpsf, status);
+
+#endif
+ get_BID128_very_fast (&res, sign_x, exponent_y, CR);
+ BID_RETURN (res);
+ }
+ if (total_digits < 0) {
+ CR.w[1] = CR.w[0] = 0;
+#ifndef IEEE_ROUND_NEAREST_TIES_AWAY
+#ifndef IEEE_ROUND_NEAREST
+ rmode = rnd_mode;
+ if (sign_x && (unsigned) (rmode - 1) < 2)
+ rmode = 3 - rmode;
+ if (rmode == ROUNDING_UP)
+ CR.w[0] = 1;
+#endif
+#endif
+#ifdef SET_STATUS_FLAGS
+ __set_status_flags (pfpsf, INEXACT_EXCEPTION);
+#endif
+ get_BID128_very_fast (&res, sign_x, exponent_y, CR);
+ BID_RETURN (res);
+ }
+ // else more than 34 digits in coefficient
+#ifdef SET_STATUS_FLAGS
+ __set_status_flags (pfpsf, INVALID_EXCEPTION);
+#endif
+ res.w[1] = 0x7c00000000000000ull;
+ res.w[0] = 0;
+ BID_RETURN (res);
+
+}
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