1/* Copyright (C) 2007-2020 Free Software Foundation, Inc.
2
3This file is part of GCC.
4
5GCC is free software; you can redistribute it and/or modify it under
6the terms of the GNU General Public License as published by the Free
7Software Foundation; either version 3, or (at your option) any later
8version.
9
10GCC is distributed in the hope that it will be useful, but WITHOUT ANY
11WARRANTY; without even the implied warranty of MERCHANTABILITY or
12FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
13for more details.
14
15Under Section 7 of GPL version 3, you are granted additional
16permissions described in the GCC Runtime Library Exception, version
173.1, as published by the Free Software Foundation.
18
19You should have received a copy of the GNU General Public License and
20a copy of the GCC Runtime Library Exception along with this program;
21see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
22<http://www.gnu.org/licenses/>.  */
23
24#define BID_128RES
25#include "bid_internal.h"
26
27#define DECIMAL_EXPONENT_BIAS_128 6176
28#define MAX_DECIMAL_EXPONENT_128  12287
29
30
31
32BID128_FUNCTION_ARG128_ARGTYPE2 (bid128_scalb, x, int, n)
33
34     UINT128 CX, CX2, CX8, res;
35     SINT64 exp64;
36     UINT64 sign_x;
37     int exponent_x, rmode;
38
39  // unpack arguments, check for NaN or Infinity
40if (!unpack_BID128_value (&sign_x, &exponent_x, &CX, x)) {
41    // x is Inf. or NaN or 0
42#ifdef SET_STATUS_FLAGS
43if ((x.w[1] & SNAN_MASK64) == SNAN_MASK64)	// y is sNaN
44  __set_status_flags (pfpsf, INVALID_EXCEPTION);
45#endif
46res.w[1] = CX.w[1] & QUIET_MASK64;
47res.w[0] = CX.w[0];
48if (!CX.w[1]) {
49       exp64 = (SINT64) exponent_x + (SINT64) n;
50	   if(exp64<0) exp64=0;
51	   if(exp64>MAX_DECIMAL_EXPONENT_128) exp64=MAX_DECIMAL_EXPONENT_128;
52       exponent_x = exp64;
53  get_BID128_very_fast (&res, sign_x, exponent_x, CX);
54}
55BID_RETURN (res);
56}
57
58exp64 = (SINT64) exponent_x + (SINT64) n;
59exponent_x = exp64;
60
61if ((UINT32) exponent_x <= MAX_DECIMAL_EXPONENT_128) {
62  get_BID128_very_fast (&res, sign_x, exponent_x, CX);
63  BID_RETURN (res);
64}
65  // check for overflow
66if (exp64 > MAX_DECIMAL_EXPONENT_128) {
67  if (CX.w[1] < 0x314dc6448d93ull) {
68    // try to normalize coefficient
69    do {
70      CX8.w[1] = (CX.w[1] << 3) | (CX.w[0] >> 61);
71      CX8.w[0] = CX.w[0] << 3;
72      CX2.w[1] = (CX.w[1] << 1) | (CX.w[0] >> 63);
73      CX2.w[0] = CX.w[0] << 1;
74      __add_128_128 (CX, CX2, CX8);
75
76      exponent_x--;
77      exp64--;
78    }
79    while (CX.w[1] < 0x314dc6448d93ull
80	   && exp64 > MAX_DECIMAL_EXPONENT_128);
81
82  }
83  if (exp64 <= MAX_DECIMAL_EXPONENT_128) {
84    get_BID128_very_fast (&res, sign_x, exponent_x, CX);
85    BID_RETURN (res);
86  } else
87    exponent_x = 0x7fffffff;	// overflow
88}
89  // exponent < 0
90  // the BID pack routine will round the coefficient
91rmode = rnd_mode;
92get_BID128 (&res, sign_x, exponent_x, CX, (unsigned int *) &rmode,
93	    pfpsf);
94BID_RETURN (res);
95
96}
97