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      6 <title>const-class</title>
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     11 
     12 <h1>const-class</h1>
     13 
     14 <h2>Purpose</h2>
     15 
     16 <p>
     17 Move a reference to the class specified by the given index into the specified
     18 register. In the case where the indicated type is primitive, this will store a
     19 reference to the primitive type's degenerate class. 
     20 </p>
     21 
     22 <h2>Details</h2>
     23 
     24 <table class="instruc">
     25 <thead>
     26 <tr>
     27   <th>Op &amp; Format</th>
     28   <th>Mnemonic / Syntax</th>
     29   <th>Arguments</th>
     30 </tr>
     31 </thead>
     32 <tbody>
     33 <tr>
     34   <td>1c 21c</td>
     35   <td>const-class vAA, type@BBBB</td>
     36   <td><code>A:</code> destination register (8 bits)<br/>
     37     <code>B:</code> type index</td>
     38 </tr>
     39 </tbody>
     40 </table>
     41 
     42 <h2>Constraints</h2>
     43 
     44 <ul>
     45   <li>
     46     A must be a valid register index in the current stack frame.
     47   </li>
     48   <li>
     49     B must be a valid index into the type constant pool.
     50   </li>
     51 </ul>
     52 
     53 <h2>Behavior</h2>
     54 
     55 <ul>
     56   <li>
     57     An attempt is made to get a reference to the class C the name of which is
     58     contained in type pool entry B.
     59   </li>
     60   <li>
     61     If B refers to a primitive type, the corresponding degenerate class is used
     62     instead.
     63   </li>
     64   <li>
     65     If C has not been loaded and resolved before, it is being loaded and
     66     resolved. All exceptions that are possible during class loading can occur at
     67     this point.
     68   </li>
     69   <li>
     70     A reference to C is moved into register vA, that is, vA' = C.
     71   </li>
     72   <li>
     73     If v(A-1) is the lower half of a register pair, v(A-1)' becomes undefined.
     74   </li>
     75   <li>
     76     If v(A+1) is the upper half of a register pair, v(A+1)' becomes undefined.
     77   </li>
     78 </ul>
     79 
     80 <h2>Exceptions</h2>
     81 
     82 <ul>
     83   <li>
     84     ClassNotFoundException is thrown if the class does not exist at all.
     85   </li>
     86   <li>
     87     VerifyError is thrown if the class does exist, but could not be verified.
     88   </li>
     89 </ul>
     90 
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