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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, 2017 The Regents of the
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| 8 | University of 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_fast32_t
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| 45 | softfloat_roundToI32(
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| 46 | bool sign, uint_fast64_t sig, uint_fast8_t roundingMode, bool exact SOFTFLOAT_STATE_DECL_COMMA )
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| 47 | {
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| 48 | uint_fast16_t roundIncrement, roundBits;
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| 49 | uint_fast32_t sig32;
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| 50 | union { uint32_t ui; int32_t i; } uZ;
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| 51 | int_fast32_t z;
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| 52 |
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| 53 | /*------------------------------------------------------------------------
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| 54 | *------------------------------------------------------------------------*/
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| 55 | roundIncrement = 0x800;
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| 56 | if (
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| 57 | (roundingMode != softfloat_round_near_maxMag)
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| 58 | && (roundingMode != softfloat_round_near_even)
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| 59 | ) {
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| 60 | roundIncrement = 0;
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| 61 | if (
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| 62 | sign
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| 63 | ? (roundingMode == softfloat_round_min)
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| 64 | #ifdef SOFTFLOAT_ROUND_ODD
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| 65 | || (roundingMode == softfloat_round_odd)
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| 66 | #endif
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| 67 | : (roundingMode == softfloat_round_max)
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| 68 | ) {
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| 69 | roundIncrement = 0xFFF;
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| 70 | }
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| 71 | }
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| 72 | roundBits = sig & 0xFFF;
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| 73 | sig += roundIncrement;
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| 74 | if ( sig & UINT64_C( 0xFFFFF00000000000 ) ) goto invalid;
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| 75 | sig32 = sig>>12;
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| 76 | if (
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| 77 | (roundBits == 0x800) && (roundingMode == softfloat_round_near_even)
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| 78 | ) {
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| 79 | sig32 &= ~(uint_fast32_t) 1;
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| 80 | }
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| 81 | uZ.ui = sign ? -sig32 : sig32;
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| 82 | z = uZ.i;
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| 83 | if ( z && ((z < 0) ^ sign) ) goto invalid;
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| 84 | if ( roundBits ) {
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| 85 | #ifdef SOFTFLOAT_ROUND_ODD
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| 86 | if ( roundingMode == softfloat_round_odd ) z |= 1;
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| 87 | #endif
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| 88 | if ( exact ) softfloat_exceptionFlags |= softfloat_flag_inexact;
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| 89 | }
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| 90 | return z;
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| 91 | /*------------------------------------------------------------------------
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| 92 | *------------------------------------------------------------------------*/
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| 93 | invalid:
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| 94 | softfloat_raiseFlags( softfloat_flag_invalid SOFTFLOAT_STATE_ARG_COMMA );
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| 95 | return sign ? i32_fromNegOverflow : i32_fromPosOverflow;
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| 96 |
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| 97 | }
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| 98 |
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