js/src/tests/ecma/Expressions/11.7.3.js

Wed, 31 Dec 2014 06:09:35 +0100

author
Michael Schloh von Bennewitz <michael@schloh.com>
date
Wed, 31 Dec 2014 06:09:35 +0100
changeset 0
6474c204b198
permissions
-rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

michael@0 1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0 2 /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0 3 * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0 4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0 5
michael@0 6
michael@0 7 /**
michael@0 8 File Name: 11.7.3.js
michael@0 9 ECMA Section: 11.7.3 The unsigned right shift operator ( >>> )
michael@0 10 Description:
michael@0 11 11.7.3 The unsigned right shift operator ( >>> )
michael@0 12 Performs a zero-filling bitwise right shift operation on the left argument
michael@0 13 by the amount specified by the right argument.
michael@0 14
michael@0 15 The production ShiftExpression : ShiftExpression >>> AdditiveExpression is
michael@0 16 evaluated as follows:
michael@0 17
michael@0 18 1. Evaluate ShiftExpression.
michael@0 19 2. Call GetValue(Result(1)).
michael@0 20 3. Evaluate AdditiveExpression.
michael@0 21 4. Call GetValue(Result(3)).
michael@0 22 5. Call ToUint32(Result(2)).
michael@0 23 6. Call ToUint32(Result(4)).
michael@0 24 7. Mask out all but the least significant 5 bits of Result(6), that is,
michael@0 25 compute Result(6) & 0x1F.
michael@0 26 8. Perform zero-filling right shift of Result(5) by Result(7) bits.
michael@0 27 Vacated bits are filled with zero. The result is an unsigned 32 bit
michael@0 28 integer.
michael@0 29 9. Return Result(8).
michael@0 30
michael@0 31 Author: christine@netscape.com
michael@0 32 Date: 12 november 1997
michael@0 33 */
michael@0 34 var SECTION = "11.7.3";
michael@0 35 var VERSION = "ECMA_1";
michael@0 36 startTest();
michael@0 37
michael@0 38 writeHeaderToLog( SECTION + " The unsigned right shift operator ( >>> )");
michael@0 39
michael@0 40 var addexp = 0;
michael@0 41 var power = 0;
michael@0 42
michael@0 43 for ( power = 0; power <= 32; power++ ) {
michael@0 44 shiftexp = Math.pow( 2, power );
michael@0 45
michael@0 46 for ( addexp = 0; addexp <= 32; addexp++ ) {
michael@0 47 new TestCase( SECTION,
michael@0 48 shiftexp + " >>> " + addexp,
michael@0 49 UnsignedRightShift( shiftexp, addexp ),
michael@0 50 shiftexp >>> addexp );
michael@0 51 }
michael@0 52 }
michael@0 53
michael@0 54 test();
michael@0 55
michael@0 56
michael@0 57 function ToInteger( n ) {
michael@0 58 n = Number( n );
michael@0 59 var sign = ( n < 0 ) ? -1 : 1;
michael@0 60
michael@0 61 if ( n != n ) {
michael@0 62 return 0;
michael@0 63 }
michael@0 64 if ( Math.abs( n ) == 0 || Math.abs( n ) == Number.POSITIVE_INFINITY ) {
michael@0 65 return n;
michael@0 66 }
michael@0 67 return ( sign * Math.floor(Math.abs(n)) );
michael@0 68 }
michael@0 69 function ToInt32( n ) {
michael@0 70 n = Number( n );
michael@0 71 var sign = ( n < 0 ) ? -1 : 1;
michael@0 72
michael@0 73 if ( Math.abs( n ) == 0 || Math.abs( n ) == Number.POSITIVE_INFINITY) {
michael@0 74 return 0;
michael@0 75 }
michael@0 76
michael@0 77 n = (sign * Math.floor( Math.abs(n) )) % Math.pow(2,32);
michael@0 78 n = ( n >= Math.pow(2,31) ) ? n - Math.pow(2,32) : n;
michael@0 79
michael@0 80 return ( n );
michael@0 81 }
michael@0 82 function ToUint32( n ) {
michael@0 83 n = Number( n );
michael@0 84 var sign = ( n < 0 ) ? -1 : 1;
michael@0 85
michael@0 86 if ( Math.abs( n ) == 0 || Math.abs( n ) == Number.POSITIVE_INFINITY) {
michael@0 87 return 0;
michael@0 88 }
michael@0 89 n = sign * Math.floor( Math.abs(n) )
michael@0 90
michael@0 91 n = n % Math.pow(2,32);
michael@0 92
michael@0 93 if ( n < 0 ){
michael@0 94 n += Math.pow(2,32);
michael@0 95 }
michael@0 96
michael@0 97 return ( n );
michael@0 98 }
michael@0 99 function ToUint16( n ) {
michael@0 100 var sign = ( n < 0 ) ? -1 : 1;
michael@0 101
michael@0 102 if ( Math.abs( n ) == 0 || Math.abs( n ) == Number.POSITIVE_INFINITY) {
michael@0 103 return 0;
michael@0 104 }
michael@0 105
michael@0 106 n = ( sign * Math.floor( Math.abs(n) ) ) % Math.pow(2,16);
michael@0 107
michael@0 108 if (n <0) {
michael@0 109 n += Math.pow(2,16);
michael@0 110 }
michael@0 111
michael@0 112 return ( n );
michael@0 113 }
michael@0 114 function Mask( b, n ) {
michael@0 115 b = ToUint32BitString( b );
michael@0 116 b = b.substring( b.length - n );
michael@0 117 b = ToUint32Decimal( b );
michael@0 118 return ( b );
michael@0 119 }
michael@0 120 function ToUint32BitString( n ) {
michael@0 121 var b = "";
michael@0 122 for ( p = 31; p >=0; p-- ) {
michael@0 123 if ( n >= Math.pow(2,p) ) {
michael@0 124 b += "1";
michael@0 125 n -= Math.pow(2,p);
michael@0 126 } else {
michael@0 127 b += "0";
michael@0 128 }
michael@0 129 }
michael@0 130 return b;
michael@0 131 }
michael@0 132 function ToInt32BitString( n ) {
michael@0 133 var b = "";
michael@0 134 var sign = ( n < 0 ) ? -1 : 1;
michael@0 135
michael@0 136 b += ( sign == 1 ) ? "0" : "1";
michael@0 137
michael@0 138 for ( p = 30; p >=0; p-- ) {
michael@0 139 if ( (sign == 1 ) ? sign * n >= Math.pow(2,p) : sign * n > Math.pow(2,p) ) {
michael@0 140 b += ( sign == 1 ) ? "1" : "0";
michael@0 141 n -= sign * Math.pow( 2, p );
michael@0 142 } else {
michael@0 143 b += ( sign == 1 ) ? "0" : "1";
michael@0 144 }
michael@0 145 }
michael@0 146
michael@0 147 return b;
michael@0 148 }
michael@0 149 function ToInt32Decimal( bin ) {
michael@0 150 var r = 0;
michael@0 151 var sign;
michael@0 152
michael@0 153 if ( Number(bin.charAt(0)) == 0 ) {
michael@0 154 sign = 1;
michael@0 155 r = 0;
michael@0 156 } else {
michael@0 157 sign = -1;
michael@0 158 r = -(Math.pow(2,31));
michael@0 159 }
michael@0 160
michael@0 161 for ( var j = 0; j < 31; j++ ) {
michael@0 162 r += Math.pow( 2, j ) * Number(bin.charAt(31-j));
michael@0 163 }
michael@0 164
michael@0 165 return r;
michael@0 166 }
michael@0 167 function ToUint32Decimal( bin ) {
michael@0 168 var r = 0;
michael@0 169
michael@0 170
michael@0 171 for ( l = bin.length; l < 32; l++ ) {
michael@0 172 bin = "0" + bin;
michael@0 173 }
michael@0 174
michael@0 175 for ( j = 0; j < 32; j++ ) {
michael@0 176 r += Math.pow( 2, j ) * Number(bin.charAt(31-j));
michael@0 177
michael@0 178 }
michael@0 179
michael@0 180 return r;
michael@0 181 }
michael@0 182 function RShift( s, a ) {
michael@0 183 s = ToUint32BitString( s );
michael@0 184 for ( z = 0; z < a; z++ ) {
michael@0 185 s = "0" + s;
michael@0 186 }
michael@0 187 s = s.substring( 0, s.length - a );
michael@0 188
michael@0 189 return ToUint32Decimal(s);
michael@0 190 }
michael@0 191 function UnsignedRightShift( s, a ) {
michael@0 192 s = ToUint32( s );
michael@0 193 a = ToUint32( a );
michael@0 194 a = Mask( a, 5 );
michael@0 195 return ( RShift( s, a ) );
michael@0 196 }

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