| The Android Open Source Project | f6c3871 | 2009-03-03 19:28:47 -0800 | [diff] [blame] | 1 | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> |
| 2 | |
| 3 | <html> |
| 4 | |
| 5 | <head> |
| 6 | <title>sget<kind></title> |
| 7 | <link rel=stylesheet href="opcode.css"> |
| 8 | </head> |
| 9 | |
| 10 | <body> |
| 11 | |
| 12 | <h1>sget<kind></h1> |
| 13 | |
| 14 | <h2>Purpose</h2> |
| 15 | |
| 16 | <p> |
| 17 | Perform the identified object static field operation with the identified static |
| 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 & Format</th> |
| 31 | <th>Mnemonic / Syntax</th> |
| 32 | <th>Arguments</th> |
| 33 | </tr> |
| 34 | </thead> |
| 35 | <tbody> |
| 36 | <tr> |
| 37 | <td>60..6d 21c</td> |
| 38 | <td>s<i>staticop</i> vAA, field@BBBB<br/> |
| 39 | 60: sget<br/> |
| 40 | 61: sget-wide<br/> |
| 41 | 62: sget-object<br/> |
| 42 | 63: sget-boolean<br/> |
| 43 | 64: sget-byte<br/> |
| 44 | 65: sget-char<br/> |
| 45 | 66: sget-short<br/> |
| 46 | </td> |
| 47 | <td><code>A:</code> dest value register or pair; (8 bits)<br/> |
| 48 | <code>B:</code> static field reference index (16 bits)</td> |
| 49 | </tr> |
| 50 | </tbody> |
| 51 | </table> |
| 52 | |
| 53 | <h2>Constraints</h2> |
| 54 | |
| 55 | <ul> |
| 56 | <li> |
| 57 | A must be a valid register index in the current stackframe. |
| 58 | </li> |
| 59 | <li> |
| 60 | For the -wide variant, also A+1 must be a valid register index in the |
| 61 | current stackframe. |
| 62 | </li> |
| 63 | <li> |
| 64 | B must be a valid index into the field reference pool. |
| 65 | </li> |
| 66 | <li> |
| 67 | The field denoted by B must be static. The type of the field denoted by B |
| 68 | must match the variant of the instruction. |
| 69 | </li> |
| 70 | </ul> |
| 71 | |
| 72 | <h2>Behavior</h2> |
| 73 | |
| 74 | <ul> |
| 75 | <li> |
| 76 | The value of the given instance field is read from the given object and |
| 77 | moved into the given register vA, that is, vA'=<class>.<field>. |
| 78 | </li> |
| 79 | <li> |
| 80 | If v(A-1) is the lower half of a register pair, v(A-1)' becomes undefined. |
| 81 | </li> |
| 82 | <li> |
| 83 | For all but the -wide variant, if v(A+1) is the upper half of a register |
| 84 | pair, v(A+1)' becomes undefined. |
| 85 | </li> |
| 86 | <li> |
| 87 | For the -wide variant, if v(A+2) is the upper half of a register pair, |
| 88 | v(A+2)' becomes undefined. |
| 89 | </li> |
| 90 | </ul> |
| 91 | |
| 92 | <h2>Exceptions</h2> |
| 93 | |
| 94 | <ul> |
| 95 | <li> |
| 96 | NullPointerException if object is null. |
| 97 | </li> |
| 98 | <li> |
| 99 | IllegalAccessException if <object>.<field> is not visible from |
| 100 | the current context according to the usual visibility and access rules of |
| 101 | the Java programming language. |
| 102 | </li> |
| 103 | </ul> |
| 104 | |
| 105 | </body> |
| 106 | </html> |