1
2/*============================================================================
3
4This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
5Package, Release 3e, by John R. Hauser.
6
7Copyright 2011, 2012, 2013, 2014, 2015, 2016 The Regents of the University of
8California.  All rights reserved.
9
10Redistribution and use in source and binary forms, with or without
11modification, are permitted provided that the following conditions are met:
12
13 1. Redistributions of source code must retain the above copyright notice,
14    this list of conditions, and the following disclaimer.
15
16 2. Redistributions in binary form must reproduce the above copyright notice,
17    this list of conditions, and the following disclaimer in the documentation
18    and/or other materials provided with the distribution.
19
20 3. Neither the name of the University nor the names of its contributors may
21    be used to endorse or promote products derived from this software without
22    specific prior written permission.
23
24THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS", AND ANY
25EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
26WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE
27DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
28DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
29(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
30LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
31ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34
35=============================================================================*/
36
37#include <stdbool.h>
38#include <stdint.h>
39#include "platform.h"
40#include "internals.h"
41#include "specialize.h"
42#include "softfloat.h"
43
44#ifdef SOFTFLOAT_FAST_INT64
45
46int_fast32_t extF80M_to_i32_r_minMag( const extFloat80_t *aPtr, bool exact )
47{
48
49    return extF80_to_i32_r_minMag( *aPtr, exact );
50
51}
52
53#else
54
55int_fast32_t extF80M_to_i32_r_minMag( const extFloat80_t *aPtr, bool exact )
56{
57    const struct extFloat80M *aSPtr;
58    uint_fast16_t uiA64;
59    int32_t exp;
60    uint64_t sig;
61    int32_t shiftDist;
62    bool sign, raiseInexact;
63    int32_t z;
64    uint64_t shiftedSig;
65    uint32_t absZ;
66    union { uint32_t ui; int32_t i; } u;
67
68    /*------------------------------------------------------------------------
69    *------------------------------------------------------------------------*/
70    aSPtr = (const struct extFloat80M *) aPtr;
71    uiA64 = aSPtr->signExp;
72    exp = expExtF80UI64( uiA64 );
73    sig = aSPtr->signif;
74    /*------------------------------------------------------------------------
75    *------------------------------------------------------------------------*/
76    if ( ! sig && (exp != 0x7FFF) ) return 0;
77    shiftDist = 0x403E - exp;
78    if ( 64 <= shiftDist ) {
79        raiseInexact = exact;
80        z = 0;
81    } else {
82        sign = signExtF80UI64( uiA64 );
83        raiseInexact = false;
84        if ( shiftDist < 0 ) {
85            if ( sig>>32 || (shiftDist <= -31) ) goto invalid;
86            shiftedSig = (uint64_t) (uint32_t) sig<<-shiftDist;
87            if ( shiftedSig>>32 ) goto invalid;
88            absZ = shiftedSig;
89        } else {
90            shiftedSig = sig;
91            if ( shiftDist ) shiftedSig >>= shiftDist;
92            if ( shiftedSig>>32 ) goto invalid;
93            absZ = shiftedSig;
94            if ( exact && shiftDist ) {
95                raiseInexact = ((uint64_t) absZ<<shiftDist != sig);
96            }
97        }
98        if ( sign ) {
99            if ( 0x80000000 < absZ ) goto invalid;
100            u.ui = -absZ;
101            z = u.i;
102        } else {
103            if ( 0x80000000 <= absZ ) goto invalid;
104            z = absZ;
105        }
106    }
107    if ( raiseInexact ) softfloat_raiseFlags( softfloat_flag_inexact );
108    return z;
109    /*------------------------------------------------------------------------
110    *------------------------------------------------------------------------*/
111 invalid:
112    softfloat_raiseFlags( softfloat_flag_invalid );
113    return
114        (exp == 0x7FFF) && (sig & UINT64_C( 0x7FFFFFFFFFFFFFFF )) ? i32_fromNaN
115            : sign ? i32_fromNegOverflow : i32_fromPosOverflow;
116
117}
118
119#endif
120
121