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| <title>const-class</title> |
| <link rel=stylesheet href="opcode.css"> |
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| <h1>const-class</h1> |
| |
| <h2>Purpose</h2> |
| |
| <p> |
| Move a reference to the class specified by the given index into the specified |
| register. In the case where the indicated type is primitive, this will store a |
| reference to the primitive type's degenerate class. |
| </p> |
| |
| <h2>Details</h2> |
| |
| <table class="instruc"> |
| <thead> |
| <tr> |
| <th>Op & Format</th> |
| <th>Mnemonic / Syntax</th> |
| <th>Arguments</th> |
| </tr> |
| </thead> |
| <tbody> |
| <tr> |
| <td>1c 21c</td> |
| <td>const-class vAA, type@BBBB</td> |
| <td><code>A:</code> destination register (8 bits)<br/> |
| <code>B:</code> type index</td> |
| </tr> |
| </tbody> |
| </table> |
| |
| <h2>Constraints</h2> |
| |
| <ul> |
| <li> |
| A must be a valid register index in the current stack frame. |
| </li> |
| <li> |
| B must be a valid index into the type constant pool. |
| </li> |
| </ul> |
| |
| <h2>Behavior</h2> |
| |
| <ul> |
| <li> |
| An attempt is made to get a reference to the class C the name of which is |
| contained in type pool entry B. |
| </li> |
| <li> |
| If B refers to a primitive type, the corresponding degenerate class is used |
| instead. |
| </li> |
| <li> |
| If C has not been loaded and resolved before, it is being loaded and |
| resolved. All exceptions that are possible during class loading can occur at |
| this point. |
| </li> |
| <li> |
| A reference to C is moved into register vA, that is, vA' = C. |
| </li> |
| <li> |
| If v(A-1) is the lower half of a register pair, v(A-1)' becomes undefined. |
| </li> |
| <li> |
| If v(A+1) is the upper half of a register pair, v(A+1)' becomes undefined. |
| </li> |
| </ul> |
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| <h2>Exceptions</h2> |
| |
| <ul> |
| <li> |
| ClassNotFoundException is thrown if the class does not exist at all. |
| </li> |
| <li> |
| VerifyError is thrown if the class does exist, but could not be verified. |
| </li> |
| </ul> |
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