christoph/lecture-compilers
1
Fork 0
Code Actions Activity

fix bug with unary precedence

Browse Source
This commit is contained in:
Christoph
2021-01-21 19:02:48 +01:00
parent 19a30632d4
commit 8fe5659f21
1 changed files with 14 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

15
src/main/java/parser/ast/ASTBalancer.java
View File

@ -2,12 +2,14 @@ package parser.ast;
import java.util.Collections;
import java.util.Map;
import java.util.Set;
import static util.Logger.log;
public final class ASTBalancer {
private static final Map<String, Integer> priority;
private static final Set<String> unary;
//!: Operatorpräzedenz
// 0 - Unary: -, +, !
@ -32,6 +34,8 @@ public final class ASTBalancer {
Map.entry("NOT_EQUAL", 4),
Map.entry("AND", 5),
Map.entry("OR", 6));
unary = Set.of("NOT", "ADD", "SUB");
}
private ASTBalancer() {}
@ -90,6 +94,7 @@ public final class ASTBalancer {
// Die Letzte Rotation ist keine richtige Rotation, dort wird false zurückgegeben
private static boolean specialLeftRotate(ASTNode root) {
log("Special-Left-Rotation around " + root.getName());
log(root.toString());
final ASTNode left = root.getChildren().get(0);
final ASTNode right = root.getChildren().get(1);
@ -158,12 +163,20 @@ public final class ASTBalancer {
return false;
}
// Unary operators have the highest precedence
if (child.getChildren().size() == 1 && unary.contains(child.getValue())) {
return false;
}
// Less equals higher
return priority.get(parent.getValue()) < priority.get(child.getValue());
{
return priority.get(parent.getValue()) < priority.get(child.getValue());
}
}
private static void simpleRightRotate(ASTNode root) {
log("Right-Rotation around " + root.getName() + ": " + root.getValue());
log(root.toString());
final ASTNode left = root.getChildren().get(0);
final ASTNode right = root.getChildren().get(1);