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Diffstat (limited to 'js/src/tests/ecma/Expressions/11.7.2.js')
| -rw-r--r-- | js/src/tests/ecma/Expressions/11.7.2.js | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/js/src/tests/ecma/Expressions/11.7.2.js b/js/src/tests/ecma/Expressions/11.7.2.js new file mode 100644 index 000000000..95cee343b --- /dev/null +++ b/js/src/tests/ecma/Expressions/11.7.2.js @@ -0,0 +1,212 @@ +/* -*- tab-width: 2; indent-tabs-mode: nil; js-indent-level: 2 -*- */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + + +/** + File Name: 11.7.2.js + ECMA Section: 11.7.2 The signed right shift operator ( >> ) + Description: + Performs a sign-filling bitwise right shift operation on the left argument + by the amount specified by the right argument. + + The production ShiftExpression : ShiftExpression >> AdditiveExpression is + evaluated as follows: + + 1. Evaluate ShiftExpression. + 2. Call GetValue(Result(1)). + 3. Evaluate AdditiveExpression. + 4. Call GetValue(Result(3)). + 5. Call ToInt32(Result(2)). + 6. Call ToUint32(Result(4)). + 7. Mask out all but the least significant 5 bits of Result(6), that is, + compute Result(6) & 0x1F. + 8. Perform sign-extending right shift of Result(5) by Result(7) bits. The + most significant bit is propagated. The result is a signed 32 bit + integer. + 9. Return Result(8). + + Author: christine@netscape.com + Date: 12 november 1997 +*/ +var SECTION = "11.7.2"; +var VERSION = "ECMA_1"; +startTest(); + +writeHeaderToLog( SECTION + " The signed right shift operator ( >> )"); + +var power = 0; +var addexp = 0; + +for ( power = 0; power <= 32; power++ ) { + shiftexp = Math.pow( 2, power ); + + for ( addexp = 0; addexp <= 32; addexp++ ) { + new TestCase( SECTION, + shiftexp + " >> " + addexp, + SignedRightShift( shiftexp, addexp ), + shiftexp >> addexp ); + } +} + +for ( power = 0; power <= 32; power++ ) { + shiftexp = -Math.pow( 2, power ); + + for ( addexp = 0; addexp <= 32; addexp++ ) { + new TestCase( SECTION, + shiftexp + " >> " + addexp, + SignedRightShift( shiftexp, addexp ), + shiftexp >> addexp ); + } +} + +test(); + +function ToInteger( n ) { + n = Number( n ); + var sign = ( n < 0 ) ? -1 : 1; + + if ( n != n ) { + return 0; + } + if ( Math.abs( n ) == 0 || Math.abs( n ) == Number.POSITIVE_INFINITY ) { + return n; + } + return ( sign * Math.floor(Math.abs(n)) ); +} +function ToInt32( n ) { + n = Number( n ); + var sign = ( n < 0 ) ? -1 : 1; + + if ( Math.abs( n ) == 0 || Math.abs( n ) == Number.POSITIVE_INFINITY) { + return 0; + } + + n = (sign * Math.floor( Math.abs(n) )) % Math.pow(2,32); + n = ( n >= Math.pow(2,31) ) ? n - Math.pow(2,32) : n; + + return ( n ); +} +function ToUint32( n ) { + n = Number( n ); + var sign = ( n < 0 ) ? -1 : 1; + + if ( Math.abs( n ) == 0 || Math.abs( n ) == Number.POSITIVE_INFINITY) { + return 0; + } + n = sign * Math.floor( Math.abs(n) ) + + n = n % Math.pow(2,32); + + if ( n < 0 ){ + n += Math.pow(2,32); + } + + return ( n ); +} +function ToUint16( n ) { + var sign = ( n < 0 ) ? -1 : 1; + + if ( Math.abs( n ) == 0 || Math.abs( n ) == Number.POSITIVE_INFINITY) { + return 0; + } + + n = ( sign * Math.floor( Math.abs(n) ) ) % Math.pow(2,16); + + if (n <0) { + n += Math.pow(2,16); + } + + return ( n ); +} +function Mask( b, n ) { + b = ToUint32BitString( b ); + b = b.substring( b.length - n ); + b = ToUint32Decimal( b ); + return ( b ); +} +function ToUint32BitString( n ) { + var b = ""; + for ( p = 31; p >=0; p-- ) { + if ( n >= Math.pow(2,p) ) { + b += "1"; + n -= Math.pow(2,p); + } else { + b += "0"; + } + } + return b; +} +function ToInt32BitString( n ) { + var b = ""; + var sign = ( n < 0 ) ? -1 : 1; + + b += ( sign == 1 ) ? "0" : "1"; + + for ( p = 30; p >=0; p-- ) { + if ( (sign == 1 ) ? sign * n >= Math.pow(2,p) : sign * n > Math.pow(2,p) ) { + b += ( sign == 1 ) ? "1" : "0"; + n -= sign * Math.pow( 2, p ); + } else { + b += ( sign == 1 ) ? "0" : "1"; + } + } + + return b; +} +function ToInt32Decimal( bin ) { + var r = 0; + var sign; + + if ( Number(bin.charAt(0)) == 0 ) { + sign = 1; + r = 0; + } else { + sign = -1; + r = -(Math.pow(2,31)); + } + + for ( var j = 0; j < 31; j++ ) { + r += Math.pow( 2, j ) * Number(bin.charAt(31-j)); + } + + return r; +} +function ToUint32Decimal( bin ) { + var r = 0; + + for ( l = bin.length; l < 32; l++ ) { + bin = "0" + bin; + } + + for ( j = 0; j < 31; j++ ) { + r += Math.pow( 2, j ) * Number(bin.charAt(31-j)); + } + + return r; +} +function SignedRightShift( s, a ) { + s = ToInt32( s ); + a = ToUint32( a ); + a = Mask( a, 5 ); + return ( SignedRShift( s, a ) ); +} +function SignedRShift( s, a ) { + s = ToInt32BitString( s ); + + var firstbit = s.substring(0,1); + + s = s.substring( 1, s.length ); + + for ( var z = 0; z < a; z++ ) { + s = firstbit + s; + } + + s = s.substring( 0, s.length - a); + + s = firstbit +s; + + + return ToInt32(ToInt32Decimal(s)); +} |