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 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 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));

 }