kai.ren | 3a9d0de | 2021-01-21 15:53:33 +0800 | [diff] [blame] | 1 | |
| 2 | /*============================================================================ |
| 3 | |
| 4 | This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic |
| 5 | Package, Release 3d, by John R. Hauser. |
| 6 | |
| 7 | Copyright 2011, 2012, 2013, 2014, 2015, 2016 The Regents of the University of |
| 8 | California. All rights reserved. |
| 9 | |
| 10 | Redistribution and use in source and binary forms, with or without |
| 11 | modification, 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 | |
| 24 | THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS", AND ANY |
| 25 | EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
| 26 | WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE |
| 27 | DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY |
| 28 | DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| 29 | (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| 30 | LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| 31 | ON 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 |
| 33 | SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 34 | |
| 35 | =============================================================================*/ |
| 36 | |
| 37 | #include <stdint.h> |
| 38 | |
| 39 | #include "platform.h" |
| 40 | #include "primitiveTypes.h" |
| 41 | |
| 42 | #ifndef softfloat_shiftRightJam256M |
| 43 | |
| 44 | static |
| 45 | void |
| 46 | softfloat_shortShiftRightJamM( |
| 47 | uint_fast8_t size_words, |
| 48 | const uint64_t *aPtr, |
| 49 | uint_fast8_t dist, |
| 50 | uint64_t *zPtr |
| 51 | ) |
| 52 | { |
| 53 | uint_fast8_t uNegDist; |
| 54 | unsigned int index, lastIndex; |
| 55 | uint64_t partWordZ, wordA; |
| 56 | |
| 57 | uNegDist = -dist; |
| 58 | index = indexWordLo( size_words ); |
| 59 | lastIndex = indexWordHi( size_words ); |
| 60 | wordA = aPtr[index]; |
| 61 | partWordZ = wordA>>dist; |
| 62 | if ( partWordZ<<dist != wordA ) partWordZ |= 1; |
| 63 | while ( index != lastIndex ) { |
| 64 | wordA = aPtr[index + wordIncr]; |
| 65 | zPtr[index] = wordA<<(uNegDist & 63) | partWordZ; |
| 66 | index += wordIncr; |
| 67 | partWordZ = wordA>>dist; |
| 68 | } |
| 69 | zPtr[index] = partWordZ; |
| 70 | |
| 71 | } |
| 72 | |
| 73 | void |
| 74 | softfloat_shiftRightJam256M( |
| 75 | const uint64_t *aPtr, uint_fast32_t dist, uint64_t *zPtr ) |
| 76 | { |
| 77 | uint64_t wordJam; |
| 78 | uint_fast32_t wordDist; |
| 79 | uint64_t *ptr; |
| 80 | uint_fast8_t i, innerDist; |
| 81 | |
| 82 | wordJam = 0; |
| 83 | wordDist = dist>>6; |
| 84 | if ( wordDist ) { |
| 85 | if ( 4 < wordDist ) wordDist = 4; |
| 86 | ptr = (uint64_t *) (aPtr + indexMultiwordLo( 4, wordDist )); |
| 87 | i = wordDist; |
| 88 | do { |
| 89 | wordJam = *ptr++; |
| 90 | if ( wordJam ) break; |
| 91 | --i; |
| 92 | } while ( i ); |
| 93 | ptr = zPtr; |
| 94 | } |
| 95 | if ( wordDist < 4 ) { |
| 96 | aPtr += indexMultiwordHiBut( 4, wordDist ); |
| 97 | innerDist = dist & 63; |
| 98 | if ( innerDist ) { |
| 99 | softfloat_shortShiftRightJamM( |
| 100 | 4 - wordDist, |
| 101 | aPtr, |
| 102 | innerDist, |
| 103 | zPtr + indexMultiwordLoBut( 4, wordDist ) |
| 104 | ); |
| 105 | if ( ! wordDist ) goto wordJam; |
| 106 | } else { |
| 107 | aPtr += indexWordLo( 4 - wordDist ); |
| 108 | ptr = zPtr + indexWordLo( 4 ); |
| 109 | for ( i = 4 - wordDist; i; --i ) { |
| 110 | *ptr = *aPtr; |
| 111 | aPtr += wordIncr; |
| 112 | ptr += wordIncr; |
| 113 | } |
| 114 | } |
| 115 | ptr = zPtr + indexMultiwordHi( 4, wordDist ); |
| 116 | } |
| 117 | do { |
| 118 | *ptr++ = 0; |
| 119 | --wordDist; |
| 120 | } while ( wordDist ); |
| 121 | wordJam: |
| 122 | if ( wordJam ) zPtr[indexWordLo( 4 )] |= 1; |
| 123 | |
| 124 | } |
| 125 | |
| 126 | #endif |
| 127 | |