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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 | uint_fast64_t f128_to_ui64_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 | uint_fast64_t z;
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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 ( sign || (shiftDist < -15) ) goto invalid;
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| 71 | sig64 |= UINT64_C( 0x0001000000000000 );
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| 72 | negShiftDist = -shiftDist;
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| 73 | z = sig64<<negShiftDist | sig0>>(shiftDist & 63);
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| 74 | if ( exact && (uint64_t) (sig0<<negShiftDist) ) {
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| 75 | softfloat_exceptionFlags |= softfloat_flag_inexact;
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| 76 | }
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| 77 | } else {
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| 78 | /*--------------------------------------------------------------------
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| 79 | *--------------------------------------------------------------------*/
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| 80 | if ( 49 <= shiftDist ) {
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| 81 | if ( exact && (exp | sig64 | sig0) ) {
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| 82 | softfloat_exceptionFlags |= softfloat_flag_inexact;
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| 83 | }
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| 84 | return 0;
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| 85 | }
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| 86 | /*--------------------------------------------------------------------
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| 87 | *--------------------------------------------------------------------*/
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| 88 | if ( sign ) goto invalid;
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| 89 | sig64 |= UINT64_C( 0x0001000000000000 );
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| 90 | z = sig64>>shiftDist;
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| 91 | if ( exact && (sig0 || (z<<shiftDist != sig64)) ) {
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| 92 | softfloat_exceptionFlags |= softfloat_flag_inexact;
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| 93 | }
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| 94 | }
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| 95 | return z;
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| 96 | /*------------------------------------------------------------------------
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| 97 | *------------------------------------------------------------------------*/
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| 98 | invalid:
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| 99 | softfloat_raiseFlags( softfloat_flag_invalid SOFTFLOAT_STATE_ARG_COMMA );
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| 100 | return
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| 101 | (exp == 0x7FFF) && (sig64 | sig0) ? ui64_fromNaN
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| 102 | : sign ? ui64_fromNegOverflow : ui64_fromPosOverflow;
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| 103 |
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| 104 | }
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| 105 |
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