Donut  |  1.6_r1
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<title>sget&lt;kind&gt;</title>
<link rel=stylesheet href="opcode.css">
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<h1>sget&lt;kind&gt;</h1>

<h2>Purpose</h2>

<p>
Perform the identified object static field operation with the identified static
field, loading or storing into the value register.
</p>
<p>
Note: These opcodes are reasonable candidates for static linking, altering the
field argument to be a more direct offset.
</p>

<h2>Details</h2>

<table class="instruc">
<thead>
<tr>
  <th>Op &amp; Format</th>
  <th>Mnemonic / Syntax</th>
  <th>Arguments</th>
</tr>
</thead>
<tbody>
<tr>
  <td>60..6d 21c</td>
  <td>s<i>staticop</i> vAA, field@BBBB<br/>
    60: sget<br/>
    61: sget-wide<br/>
    62: sget-object<br/>
    63: sget-boolean<br/>
    64: sget-byte<br/>
    65: sget-char<br/>
    66: sget-short<br/>
  </td>
  <td><code>A:</code> dest value register or pair; (8 bits)<br/>
    <code>B:</code> static field reference index (16 bits)</td>
</tr>
</tbody>
</table>

<h2>Constraints</h2>

<ul>
  <li>
    A must be a valid register index in the current stackframe.
  </li>
  <li>
    For the -wide variant, also A+1 must be a valid register index in the
    current stackframe.
  </li>
  <li>
    B must be a valid index into the field reference pool.
  </li>
  <li>
    The field denoted by B must be static. The type of the field denoted by B
    must match the variant of the instruction.
  </li>
</ul>

<h2>Behavior</h2>

<ul>
  <li>
    The value of the given instance field is read from the given object and
    moved into the given register vA, that is, vA'=&lt;class&gt;.&lt;field&gt;.
  </li>
  <li>
    If v(A-1) is the lower half of a register pair, v(A-1)' becomes undefined.
  </li>
  <li>
    For all but the -wide variant, if v(A+1) is the upper half of a register
    pair, v(A+1)' becomes undefined.
  </li>
  <li>
    For the -wide variant, if v(A+2) is the upper half of a register pair,
    v(A+2)' becomes undefined.
  </li>
</ul>

<h2>Exceptions</h2>

<ul>
  <li>
    NullPointerException if object is null.
  </li>
  <li>
    IllegalAccessException if &lt;object&gt;.&lt;field&gt; is not visible from
    the current context according to the usual visibility and access rules of
    the Java programming language.
  </li>
</ul>

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