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      6 <title>const-wide</title>
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     10 <body>
     11 
     12 <h1>const-wide</h1>
     13 
     14 <h2>Purpose</h2>
     15 
     16 <p>
     17 Move the given literal value (sign-extended to 64 bits) into the specified
     18 register-pair. 
     19 </p>
     20 
     21 <h2>Details</h2>
     22 
     23 <table class="instruc">
     24 <thead>
     25 <tr>
     26   <th>Op &amp; Format</th>
     27   <th>Mnemonic / Syntax</th>
     28   <th>Arguments</th>
     29 </tr>
     30 </thead>
     31 <tbody>
     32 <tr>
     33   <td>16 21s</td>
     34   <td>const-wide/16 vAA, #+BBBB</td>
     35   <td><code>A:</code> destination register (8 bits)<br/>
     36     <code>B:</code> signed int (16 bits)</td>
     37 </tr>
     38 <tr>
     39   <td>17 31i</td>
     40   <td>const-wide/32 vAA, #+BBBBBBBB</td>
     41   <td><code>A:</code> destination register (8 bits)<br/>
     42     <code>B:</code> signed int (32 bits)</td>
     43 </tr>
     44 <tr>
     45   <td>18 51l</td>
     46   <td>const-wide vAA, #+BBBBBBBBBBBBBBBB</td>
     47   <td><code>A:</code> destination register (8 bits)<br/>
     48     <code>B:</code> arbitrary double-width (64-bit) constant</td>
     49 </tr>
     50 <tr>
     51   <td>19 21h</td>
     52   <td>const-wide/high16 vAA, #+BBBB000000000000</td>
     53   <td><code>A:</code> destination register (8 bits)<br/>
     54     <code>B:</code> signed int (16 bits)</td>
     55 </tr>
     56 </tbody>
     57 </table>
     58 
     59 <h2>Constraints</h2>
     60 
     61 <ul>
     62   <li>
     63     A must be a valid register index in the current stack frame.
     64   </li>
     65 </ul>
     66 
     67 <h2>Behavior</h2>
     68 
     69 <ul>
     70   <li>
     71     First, an adjusted value B' is determined as follows:
     72     <ul>
     73       <li>
     74         If we are executing the /high16 variant, then B is left-shifted by 40
     75         bits, that is, B'=B << 0x28
     76       <li>
     77         Otherwise, if B is a 16 bit or 32 bit constant, it is sign-extended to
     78         64 bits, that is, B'=sign-extended(B).
     79       </li>
     80       <li>
     81         Otherwise, B'=B.
     82       </li>
     83     </ul>
     84   <li>
     85     The immediate value B is moved into the register pair (vA, v(A+1)), that is,
     86     <ul>
     87       <li>
     88         vA' = B << 0x20
     89       </li>
     90       <li>
     91         v(A+1)' = B & 0xffffffff
     92       </li>
     93     </ul>
     94   </li>
     95   <li>
     96     If v(A-1) is the lower half of a register pair, v(A-1)' becomes undefined.
     97   </li>
     98   <li>
     99     If v(A+2) is the upper half of a register pair, v(A+2)' becomes undefined.
    100   </li>
    101 </ul> 
    102 
    103 <h2>Exceptions</h2>
    104 
    105 <p>
    106 None.
    107 </p>
    108 
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