| 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>move-result-wide</title> |
| 7 | <link rel=stylesheet href="opcode.css"> |
| 8 | </head> |
| 9 | |
| 10 | <body> |
| 11 | |
| 12 | <h1>move-result-wide</h1> |
| 13 | |
| 14 | <h2>Purpose</h2> |
| 15 | |
| 16 | <p> |
| 17 | Move the double-word result of the most recent invoke-kind into the indicated |
| 18 | register pair. This must be done as the instruction immediately after an |
| 19 | invoke-kind whose (double-word) result is not to be ignored; anywhere else is |
| Carl Shapiro | de75089 | 2010-06-08 16:37:12 -0700 | [diff] [blame] | 20 | invalid. |
| The Android Open Source Project | f6c3871 | 2009-03-03 19:28:47 -0800 | [diff] [blame] | 21 | </p> |
| 22 | |
| 23 | <h2>Details</h2> |
| 24 | |
| 25 | <table class="instruc"> |
| 26 | <thead> |
| 27 | <tr> |
| 28 | <th>Op & Format</th> |
| 29 | <th>Mnemonic / Syntax</th> |
| 30 | <th>Arguments</th> |
| 31 | </tr> |
| 32 | </thead> |
| 33 | <tbody> |
| 34 | <tr> |
| 35 | <td>0b 11x</td> |
| 36 | <td>move-result-wide vAA</td> |
| 37 | <td><code>A:</code> destination register pair (8 bits)</td> |
| 38 | </tr> |
| 39 | </tbody> |
| 40 | </table> |
| 41 | |
| 42 | <h2>Constraints</h2> |
| 43 | |
| 44 | <ul> |
| 45 | <li> |
| 46 | A+1 must be a valid register index in the current stack frame (which |
| 47 | includes A itself being valid). |
| 48 | </li> |
| 49 | <li> |
| 50 | The instruction must be immediately preceded (in the code array) by an |
| 51 | invoke-kind instruction. |
| 52 | </li> |
| 53 | <li> |
| 54 | The instruction must be immediately reached (in the actual control flow) |
| 55 | through returning from this invoke-kind instruction (it must not be jumped |
| 56 | to). |
| 57 | </li> |
| 58 | <li> |
| 59 | The result delivered by the invoke-kind instruction must be either a long |
| 60 | or a double value. |
| 61 | </li> |
| 62 | </ul> |
| Carl Shapiro | de75089 | 2010-06-08 16:37:12 -0700 | [diff] [blame] | 63 | |
| The Android Open Source Project | f6c3871 | 2009-03-03 19:28:47 -0800 | [diff] [blame] | 64 | <h2>Behavior</h2> |
| 65 | |
| 66 | <ul> |
| 67 | <li> |
| 68 | The upper 32 bits of the result delivered by the invoke-kind instruction are |
| 69 | moved to register vA, that is, vA' = result >> 0x20. |
| 70 | </li> |
| 71 | <li> |
| 72 | The lower 32 bits of the result delivered by the invoke-kind instruction are |
| 73 | moved to register v(A+1), that is, v(A+1)' = result & 0xffffffff. |
| 74 | </li> |
| 75 | <li> |
| 76 | If register v(A-1) is the lower half of a register pair, register v(A-1)' |
| 77 | becomes undefined. |
| 78 | </li> |
| 79 | <li> |
| 80 | If register v(A+2) is the upper half of a register pair, register v(A+2)' |
| 81 | becomes undefined. |
| 82 | </li> |
| 83 | </ul> |
| Carl Shapiro | de75089 | 2010-06-08 16:37:12 -0700 | [diff] [blame] | 84 | |
| The Android Open Source Project | f6c3871 | 2009-03-03 19:28:47 -0800 | [diff] [blame] | 85 | <h2>Exceptions</h2> |
| 86 | |
| 87 | <p> |
| 88 | None. |
| 89 | </p> |
| 90 | |
| 91 | <h2>Notes</h2> |
| 92 | |
| 93 | <p> |
| 94 | This instruction can also be thought of as reading the contents of a special |
| 95 | "result" register that is made valid and defined by executing a non-void return |
| 96 | instruction or a filled-new-array instruction. The execution of any other |
| 97 | instruction (including this one) renders this special register invalid. |
| 98 | </p> |
| 99 | |
| 100 | </body> |
| 101 | </html> |