docs/opcodes/opcode-67-sput.html


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

<html>

<head>
<title>sput&lt;kind&gt;</title>
<link rel=stylesheet href="opcode.css">
</head>

<body>

<h1>sput&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>67..6d 21c</td>
  <td>s<i>staticop</i> vAA, field@BBBB<br/>
    67: sput<br/>
    68: sput-wide<br/>
    69: sput-object<br/>
    6a: sput-boolean<br/>
    6b: sput-byte<br/>
    6c: sput-char<br/>
    6d: sput-short
  </td>
  <td><code>A:</code> source 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 must be static. The type of the field denoted by C must match the
    variant of the instruction.
  </li>
  <li>
    For the -object variant, the instance referenced by register vA must be
    assignment-compatible to the type of the field.
  </li>
</ul>

<h2>Behavior</h2>

<ul>
  <li>
    For all but the -wide variant, the value of register vA is move into the
    field, that is, &lt;class&gt;.&lt;field&gt;'=vA.
  </li>
  <li>
    For the -wide variant, the registers vA and v(A+1) are moved into the field
    as follows:
    <ul>
      <li>
        &lt;class&gt;.&lt;field&gt;' = vA &lt;&lt; 0x20 | v(A+1)
      </li>
    </ul>
  </li>
</ul>

<h2>Exceptions</h2>

<ul>
  <li>
    NullPointerException if vB=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, or final.
  </li>
</ul>

</body>
</html>