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| <h4 class="subsection">9.50.6 VAX Operands</h4> |
| |
| <p><a name="index-VAX-operand-notation-2513"></a><a name="index-operand-notation_002c-VAX-2514"></a><a name="index-immediate-character_002c-VAX-2515"></a><a name="index-VAX-immediate-character-2516"></a>The immediate character is ‘<samp><span class="samp">$</span></samp>’ for Unix compatibility, not |
| ‘<samp><span class="samp">#</span></samp>’ as DEC writes it. |
| |
| <p><a name="index-indirect-character_002c-VAX-2517"></a><a name="index-VAX-indirect-character-2518"></a>The indirect character is ‘<samp><span class="samp">*</span></samp>’ for Unix compatibility, not |
| ‘<samp><span class="samp">@</span></samp>’ as DEC writes it. |
| |
| <p><a name="index-displacement-sizing-character_002c-VAX-2519"></a><a name="index-VAX-displacement-sizing-character-2520"></a>The displacement sizing character is ‘<samp><span class="samp">`</span></samp>’ (an accent grave) for |
| Unix compatibility, not ‘<samp><span class="samp">^</span></samp>’ as DEC writes it. The letter |
| preceding ‘<samp><span class="samp">`</span></samp>’ may have either case. ‘<samp><span class="samp">G</span></samp>’ is not |
| understood, but all other letters (<code>b i l s w</code>) are understood. |
| |
| <p><a name="index-register-names_002c-VAX-2521"></a><a name="index-VAX-register-names-2522"></a>Register names understood are <code>r0 r1 r2 ... r15 ap fp sp |
| pc</code>. Upper and lower case letters are equivalent. |
| |
| <p>For instance |
| <pre class="smallexample"> tstb *w`$4(r5) |
| </pre> |
| <p>Any expression is permitted in an operand. Operands are comma |
| separated. |
| |
| <!-- There is some bug to do with recognizing expressions --> |
| <!-- in operands, but I forget what it is. It is --> |
| <!-- a syntax clash because () is used as an address mode --> |
| <!-- and to encapsulate sub-expressions. --> |
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