1 // SPDX-License-Identifier: BSD-3-Clause
2 
3 /*============================================================================
4 
5 This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
6 Package, Release 3a, by John R. Hauser.
7 
8 Copyright 2011, 2012, 2013, 2014, 2015 The Regents of the University of
9 California.  All rights reserved.
10 
11 Redistribution and use in source and binary forms, with or without
12 modification, are permitted provided that the following conditions are met:
13 
14  1. Redistributions of source code must retain the above copyright notice,
15     this list of conditions, and the following disclaimer.
16 
17  2. Redistributions in binary form must reproduce the above copyright notice,
18     this list of conditions, and the following disclaimer in the documentation
19     and/or other materials provided with the distribution.
20 
21  3. Neither the name of the University nor the names of its contributors may
22     be used to endorse or promote products derived from this software without
23     specific prior written permission.
24 
25 THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS", AND ANY
26 EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
27 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE
28 DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
29 DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
30 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
31 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
32 ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
34 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35 
36 =============================================================================*/
37 
38 #include <stdint.h>
39 #include "platform.h"
40 #include "primitiveTypes.h"
41 
42 #ifndef softfloat_shiftRightJam256M
43 
44 static
45  void
softfloat_shortShiftRightJamM(uint_fast8_t size_words,const uint64_t * aPtr,uint_fast8_t count,uint64_t * zPtr)46   softfloat_shortShiftRightJamM(
47       uint_fast8_t size_words,
48       const uint64_t *aPtr,
49       uint_fast8_t count,
50       uint64_t *zPtr
51   )
52 {
53     uint_fast8_t negCount;
54     unsigned int index, lastIndex;
55     uint64_t partWordZ, wordA;
56 
57     negCount = -count;
58     index = indexWordLo( size_words );
59     lastIndex = indexWordHi( size_words );
60     wordA = aPtr[index];
61     partWordZ = wordA>>count;
62     if ( partWordZ<<count != wordA ) partWordZ |= 1;
63     while ( index != lastIndex ) {
64         wordA = aPtr[index + wordIncr];
65         zPtr[index] = wordA<<(negCount & 63) | partWordZ;
66         index += wordIncr;
67         partWordZ = wordA>>count;
68     }
69     zPtr[index] = partWordZ;
70 
71 }
72 
73 void
softfloat_shiftRightJam256M(const uint64_t * aPtr,uint_fast32_t count,uint64_t * zPtr)74  softfloat_shiftRightJam256M(
75      const uint64_t *aPtr, uint_fast32_t count, uint64_t *zPtr )
76 {
77     uint64_t wordJam;
78     uint_fast32_t wordCount;
79     uint64_t *ptr;
80     uint_fast8_t i, innerCount;
81 
82     wordJam = 0;
83     wordCount = count>>6;
84     if ( wordCount ) {
85         if ( 4 < wordCount ) wordCount = 4;
86         ptr = (uint64_t *) (aPtr + indexMultiwordLo( 4, wordCount ));
87         i = wordCount;
88         do {
89             wordJam = *ptr++;
90             if ( wordJam ) break;
91             --i;
92         } while ( i );
93         ptr = zPtr;
94     }
95     if ( wordCount < 4 ) {
96         aPtr += indexMultiwordHiBut( 4, wordCount );
97         innerCount = count & 63;
98         if ( innerCount ) {
99             softfloat_shortShiftRightJamM(
100                 4 - wordCount,
101                 aPtr,
102                 innerCount,
103                 zPtr + indexMultiwordLoBut( 4, wordCount )
104             );
105             if ( ! wordCount ) goto wordJam;
106         } else {
107             aPtr += indexWordLo( 4 - wordCount );
108             ptr = zPtr + indexWordLo( 4 );
109             for ( i = 4 - wordCount; i; --i ) {
110                 *ptr = *aPtr;
111                 aPtr += wordIncr;
112                 ptr += wordIncr;
113             }
114         }
115         ptr = zPtr + indexMultiwordHi( 4, wordCount );
116     }
117     do {
118         *ptr++ = 0;
119         --wordCount;
120     } while ( wordCount );
121  wordJam:
122     if ( wordJam ) zPtr[indexWordLo( 4 )] |= 1;
123 
124 }
125 
126 #endif
127 
128