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2 | /*============================================================================
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3 |
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4 | This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
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5 | Package, Release 3e, by John R. Hauser.
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6 |
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7 | Copyright 2011, 2012, 2013, 2014, 2015, 2016 The Regents of the University of
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8 | California. All rights reserved.
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9 |
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10 | Redistribution and use in source and binary forms, with or without
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11 | modification, are permitted provided that the following conditions are met:
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12 |
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13 | 1. Redistributions of source code must retain the above copyright notice,
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14 | this list of conditions, and the following disclaimer.
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15 |
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16 | 2. Redistributions in binary form must reproduce the above copyright notice,
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17 | this list of conditions, and the following disclaimer in the documentation
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18 | and/or other materials provided with the distribution.
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19 |
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20 | 3. Neither the name of the University nor the names of its contributors may
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21 | be used to endorse or promote products derived from this software without
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22 | specific prior written permission.
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23 |
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24 | THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS", AND ANY
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25 | EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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26 | WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE
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27 | DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
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28 | DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
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29 | (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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30 | LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
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31 | ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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32 | (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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33 | SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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34 |
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35 | =============================================================================*/
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36 |
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37 | #include <stdbool.h>
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38 | #include <stdint.h>
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39 | #include "platform.h"
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40 | #include "internals.h"
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41 | #include "specialize.h"
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42 | #include "softfloat.h"
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43 |
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44 | int_fast64_t f128_to_i64_r_minMag( float128_t a, bool exact SOFTFLOAT_STATE_DECL_COMMA )
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45 | {
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46 | union ui128_f128 uA;
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47 | uint_fast64_t uiA64, uiA0;
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48 | bool sign;
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49 | int_fast32_t exp;
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50 | uint_fast64_t sig64, sig0;
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51 | int_fast32_t shiftDist;
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52 | int_fast8_t negShiftDist;
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53 | int_fast64_t absZ;
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54 |
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55 | /*------------------------------------------------------------------------
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56 | *------------------------------------------------------------------------*/
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57 | uA.f = a;
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58 | uiA64 = uA.ui.v64;
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59 | uiA0 = uA.ui.v0;
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60 | sign = signF128UI64( uiA64 );
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61 | exp = expF128UI64( uiA64 );
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62 | sig64 = fracF128UI64( uiA64 );
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63 | sig0 = uiA0;
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64 | /*------------------------------------------------------------------------
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65 | *------------------------------------------------------------------------*/
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66 | shiftDist = 0x402F - exp;
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67 | if ( shiftDist < 0 ) {
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68 | /*--------------------------------------------------------------------
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69 | *--------------------------------------------------------------------*/
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70 | if ( shiftDist < -14 ) {
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71 | if (
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72 | (uiA64 == UINT64_C( 0xC03E000000000000 ))
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73 | && (sig0 < UINT64_C( 0x0002000000000000 ))
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74 | ) {
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75 | if ( exact && sig0 ) {
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76 | softfloat_exceptionFlags |= softfloat_flag_inexact;
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77 | }
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78 | return -INT64_C( 0x7FFFFFFFFFFFFFFF ) - 1;
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79 | }
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80 | softfloat_raiseFlags( softfloat_flag_invalid SOFTFLOAT_STATE_ARG_COMMA );
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81 | return
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82 | (exp == 0x7FFF) && (sig64 | sig0) ? i64_fromNaN
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83 | : sign ? i64_fromNegOverflow : i64_fromPosOverflow;
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84 | }
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85 | /*--------------------------------------------------------------------
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86 | *--------------------------------------------------------------------*/
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87 | sig64 |= UINT64_C( 0x0001000000000000 );
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88 | negShiftDist = -shiftDist;
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89 | absZ = sig64<<negShiftDist | sig0>>(shiftDist & 63);
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90 | if ( exact && (uint64_t) (sig0<<negShiftDist) ) {
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91 | softfloat_exceptionFlags |= softfloat_flag_inexact;
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92 | }
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93 | } else {
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94 | /*--------------------------------------------------------------------
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95 | *--------------------------------------------------------------------*/
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96 | if ( 49 <= shiftDist ) {
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97 | if ( exact && (exp | sig64 | sig0) ) {
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98 | softfloat_exceptionFlags |= softfloat_flag_inexact;
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99 | }
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100 | return 0;
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101 | }
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102 | /*--------------------------------------------------------------------
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103 | *--------------------------------------------------------------------*/
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104 | sig64 |= UINT64_C( 0x0001000000000000 );
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105 | absZ = sig64>>shiftDist;
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106 | if ( exact && (sig0 || (absZ<<shiftDist != sig64)) ) {
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107 | softfloat_exceptionFlags |= softfloat_flag_inexact;
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108 | }
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109 | }
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110 | return sign ? -absZ : absZ;
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111 |
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112 | }
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113 |
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