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add + improve comparison codegen

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2021-01-22 17:04:23 +01:00
parent f65cd86f32
commit e2d670bdba
1 changed files with 15 additions and 12 deletions
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27
src/main/java/codegen/CodeGenerator.java
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@ -82,6 +82,15 @@ public final class CodeGenerator {
return Collections.unmodifiableMap(varMap);
}
private static String genComparisonInst(String inst, String labelPre, int currentLabel) {
return inst + " " + labelPre + "true" + currentLabel // If not equal jump to NEtrue
+ "\n\t\tldc 0" // If false load 0
+ "\n\t\tgoto " + labelPre + "end" + currentLabel // If false skip true branch
+ "\n" + labelPre + "true" + currentLabel + ":"
+ "\n\t\tldc 1" // if true load 1
+ "\n" + labelPre + "end" + currentLabel + ":";
}
private void generateHeader(String source) {
System.out.println(" - Generating Jasmin Assembler...");
final String clazz = this.tree.getRoot().getChildren().get(1).getValue();
@ -280,18 +289,12 @@ public final class CodeGenerator {
inst = switch (node.getValue()) {
case "AND" -> "iand"; // Boolean
case "OR" -> "ior";
case "EQUAL" -> cmpeq + " EQtrue" + currentLabel // If equal jump to EQtrue
+ "\n\t\tldc 0" // If false load 0
+ "\n\t\tgoto EQend" + currentLabel // If false skip true branch
+ "\nEQtrue" + currentLabel + ":"
+ "\n\t\tldc 1" // if true load 1
+ "\nEQend" + currentLabel + ":";
case "NOT_EQUAL" -> cmpne + " NEtrue" + currentLabel // If not equal jump to NEtrue
+ "\n\t\tldc 0" // If false load 0
+ "\n\t\tgoto NEend" + currentLabel // If false skip true branch
+ "\nNEtrue" + currentLabel + ":"
+ "\n\t\tldc 1" // if true load 1
+ "\nNEend" + currentLabel + ":";
case "EQUAL" -> genComparisonInst(cmpeq, "EQ", currentLabel);
case "NOT_EQUAL" -> genComparisonInst(cmpne, "NE", currentLabel);
case "LESS" -> genComparisonInst("if_icmplt", "LT", currentLabel);
case "LESS_EQUAL" -> genComparisonInst("if_icmple", "LE", currentLabel);
case "GREATER" -> genComparisonInst("if_icmpgt", "GT", currentLabel);
case "GREATER_EQUAL" -> genComparisonInst("if_icmpge", "GE", currentLabel);
default -> throw new IllegalStateException("Unexpected value: " + node.getValue());
};
}