backend.js

/* _________________________________________________________________________
 *
 *             Tachyon : A Self-Hosted JavaScript Virtual Machine
 *
 *
 *  This file is part of the Tachyon JavaScript project. Tachyon is
 *  distributed at:
 *  http://github.com/Tachyon-Team/Tachyon
 *
 *
 *  Copyright (c) 2011, Universite de Montreal
 *  All rights reserved.
 *
 *  This software is licensed under the following license (Modified BSD
 *  License):
 *
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 *  modification, are permitted provided that the following conditions are
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 *      notice, this list of conditions and the following disclaimer.
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 * _________________________________________________________________________
 */

/**
@fileOverview
Backend interface definition.

@author
Maxime Chevalier-Boisvert
*/

/**
@class Interface class for backends. All backends should extend this class.
*/
function Backend()
{
    /**
    General-purpose register size in bits
    */
    this.regSizeBits = undefined;

    /**
    General-purpose register size in bytes
    */
    this.regSizeBytes = undefined;

    /**
    Number of general-purpose registers
    */
    this.numGpRegs = undefined;

    /**
    Endianness of the target architecture. Must be 'big' or 'little'.
    */
    this.endian = undefined;
}

/**
Link the values needing to be linked in the code generated
for an IR function.
*/
Backend.prototype.linkCode = function (irFunc, params)
{
    assert (
        irFunc instanceof IRFunction,
        'expected IR function'
    );

    // Link the code for the child functions
    for (var i = 0; i < irFunc.childFuncs.length; ++i)
        this.linkCode(irFunc.childFuncs[i], params);

    // Get the code block stored on the function object
    var codeBlock = irFunc.codeBlock;

    // Link the code block for the function
    linkCode(codeBlock, this, params);
}