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      6 <title>iget&lt;kind&gt;</title>
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     10 <body>
     11 
     12 <h1>iget&lt;kind&gt;</h1>
     13 
     14 <h2>Purpose</h2>
     15 
     16 <p>
     17 Perform the identified object instance field operation with the identified
     18 field, loading or storing into the value register.
     19 </p>
     20 <p>
     21 Note: These opcodes are reasonable candidates for static linking, altering the
     22 field argument to be a more direct offset.
     23 </p>
     24 
     25 <h2>Details</h2>
     26 
     27 <table class="instruc">
     28 <thead>
     29 <tr>
     30   <th>Op &amp; Format</th>
     31   <th>Mnemonic / Syntax</th>
     32   <th>Arguments</th>
     33 </tr>
     34 </thead>
     35 <tbody>
     36 <tr>
     37   <td>59..5f 22c</td>
     38   <td>i<i>instanceop</i> vA, vB, field@CCCC<br/>
     39     59: iput<br/>
     40     5a: iput-wide<br/>
     41     5b: iput-object<br/>
     42     5c: iput-boolean<br/>
     43     5d: iput-byte<br/>
     44     5e: iput-char<br/>
     45     5f: iput-short
     46   </td>
     47   <td><code>A:</code> source value register or pair; (4 bits)<br/>
     48     <code>B:</code> object register (4 bits)<br/>
     49     <code>C:</code> instance field reference index (16 bits)</td>
     50 </tr>
     51 </tbody>
     52 </table>
     53 
     54 <h2>Constraints</h2>
     55 
     56 <ul>
     57   <li>
     58     A and B must be valid register indices in the current stack frame.
     59   </li>
     60   <li>
     61     For the -wide variant, also A+1 must be a valid register index in the
     62     current stack frame.
     63   </li>
     64   <li>
     65     Register vB must contain an object reference.
     66   </li>
     67   <li>
     68     C must be a valid index into the field reference pool.
     69   </li>
     70   <li>
     71     The field must be an instance field. The type of the field denoted by C must
     72     match the variant of the instruction.
     73   </li>
     74   <li>
     75     For the -object variant, the instance referenced by register vA must be
     76     assignment-compatible to the type of the field.
     77   </li>
     78 </ul>
     79 
     80 <h2>Behavior</h2>
     81 
     82 <ul>
     83   <li>
     84     For all but the -wide variant, the value of register vA is move into the
     85     field, that is, &lt;object&gt;.&lt;field&gt;'=vA.
     86   </li>
     87   <li>
     88     For the -wide variant, the registers vA and v(A+1) are moved into the
     89     field as follows:
     90     <ul>
     91       <li>
     92         &lt;object&gt;.&lt;field&gt;' = vA &lt;&lt; 0x20 | v(A+1)
     93       </li>
     94     </ul>
     95   </li>
     96 </ul>
     97 
     98 <h2>Exceptions</h2>
     99 
    100 <ul>
    101   <li>
    102     NullPointerException if vB=null.
    103   </li>
    104   <li>
    105     IllegalAccessException if &lt;object&gt;.&lt;field&gt; is not visible from
    106     the current context according to the usual visibility and access rules of
    107     the Java programming language, or final.
    108   </li>
    109 </ul>
    110 
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