38 lines
1.4 KiB
Java
38 lines
1.4 KiB
Java
package io.github.applecommander.bastools.api.code;
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/**
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* A {@code CodeMark} marks a dynamic address within the output stream. When referenced, it will report the
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* most recent address is knows, forcing the generation to run multiple times until it "settles".
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* <p>
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* Multiple passes occur for the following reasons:<ul>
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* <li>an assembly address can be calculated on the second pass (1st is to actually calculate address and 2nd pass is to
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* use that address).</li>
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* <li>Applesoft BASIC encodes the address as text; that means first pass, the address is "0" but 2nd pass the address is
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* likely to be 4 digits "8123" (for example) which, in turn moves anything after that point, requiring a 3rd pass
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* to push everything out (and likely making that number become "8126" since going from 1 digit to 4 digits adds
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* 3 bytes to the preceding bytes</li>
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* </ul>
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*
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* @author rob
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*/
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public class CodeMark {
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private int address;
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public int getAddress() {
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return address;
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}
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/**
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* Update the current address based on the {@code GeneratorState}.
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* @return boolean indicating if the address changed
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*/
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public boolean update(GeneratorState state) {
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int currentAddress = state.currentAddress();
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try {
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return currentAddress != address;
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} finally {
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this.address = currentAddress;
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}
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}
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}
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