/* Copyright (C) 2007-2020 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 3, or (at your option) any later version. 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. Under Section 7 of GPL version 3, you are granted additional permissions described in the GCC Runtime Library Exception, version 3.1, as published by the Free Software Foundation. You should have received a copy of the GNU General Public License and a copy of the GCC Runtime Library Exception along with this program; see the files COPYING3 and COPYING.RUNTIME respectively. If not, see <http://www.gnu.org/licenses/>. */ #define BID_128RES #include "bid_internal.h" #define DECIMAL_EXPONENT_BIAS_128 6176 #define MAX_DECIMAL_EXPONENT_128 12287 BID128_FUNCTION_ARG128_ARGTYPE2 (bid128_scalb, x, int, n) UINT128 CX, CX2, CX8, res; SINT64 exp64; UINT64 sign_x; int exponent_x, rmode; // unpack arguments, check for NaN or Infinity if (!unpack_BID128_value (&sign_x, &exponent_x, &CX, x)) { // x is Inf. or NaN or 0 #ifdef SET_STATUS_FLAGS if ((x.w[1] & SNAN_MASK64) == SNAN_MASK64) // y is sNaN __set_status_flags (pfpsf, INVALID_EXCEPTION); #endif res.w[1] = CX.w[1] & QUIET_MASK64; res.w[0] = CX.w[0]; if (!CX.w[1]) { exp64 = (SINT64) exponent_x + (SINT64) n; if(exp64<0) exp64=0; if(exp64>MAX_DECIMAL_EXPONENT_128) exp64=MAX_DECIMAL_EXPONENT_128; exponent_x = exp64; get_BID128_very_fast (&res, sign_x, exponent_x, CX); } BID_RETURN (res); } exp64 = (SINT64) exponent_x + (SINT64) n; exponent_x = exp64; if ((UINT32) exponent_x <= MAX_DECIMAL_EXPONENT_128) { get_BID128_very_fast (&res, sign_x, exponent_x, CX); BID_RETURN (res); } // check for overflow if (exp64 > MAX_DECIMAL_EXPONENT_128) { if (CX.w[1] < 0x314dc6448d93ull) { // try to normalize coefficient do { CX8.w[1] = (CX.w[1] << 3) | (CX.w[0] >> 61); CX8.w[0] = CX.w[0] << 3; CX2.w[1] = (CX.w[1] << 1) | (CX.w[0] >> 63); CX2.w[0] = CX.w[0] << 1; __add_128_128 (CX, CX2, CX8); exponent_x--; exp64--; } while (CX.w[1] < 0x314dc6448d93ull && exp64 > MAX_DECIMAL_EXPONENT_128); } if (exp64 <= MAX_DECIMAL_EXPONENT_128) { get_BID128_very_fast (&res, sign_x, exponent_x, CX); BID_RETURN (res); } else exponent_x = 0x7fffffff; // overflow } // exponent < 0 // the BID pack routine will round the coefficient rmode = rnd_mode; get_BID128 (&res, sign_x, exponent_x, CX, (unsigned int *) &rmode, pfpsf); BID_RETURN (res); } |