add bool literal

src/main/antlr4/de/hsrm/compiler/Klang/Klang.g4

@@ -78,7 +78,8 @@ expression
 
 atom
   : INTEGER_LITERAL #intAtom
-  | IDENT # variable
+  | BOOLEAN_LITERAL #boolAtom
+  | IDENT #variable
   ;
 
 functionCall
@@ -137,6 +138,11 @@ INTEGER_LITERAL
   : [0-9]+
   ;
 
+BOOLEAN_LITERAL
+  : 'true'
+  | 'false'
+  ;
+
 IDENT
   : [a-zA-Z][a-zA-Z0-9]*
   ;

src/main/java/de/hsrm/compiler/Klang/ContextAnalysis.java

@@ -209,6 +209,13 @@ public class ContextAnalysis extends KlangBaseVisitor<Node> {
     return n;
   }
 
+  @Override
+  public Node visitBoolAtom(KlangParser.BoolAtomContext ctx) {
+    Node n = new BooleanExpression(ctx.getText().equals("true") ? true : false);
+    n.type = Type.getBooleanType();
+    return n;
+  }
+
   @Override
   public Node visitFunctionDef(KlangParser.FunctionDefContext ctx) {
     String name = ctx.funcName.getText();

src/main/java/de/hsrm/compiler/Klang/Value.java

@@ -10,4 +10,8 @@ public class Value {
     public int asInteger() {
         return (int) this.value;
     }
+
+    public boolean asBoolean() {
+        return (boolean) this.value;
+    }
 }

src/main/java/de/hsrm/compiler/Klang/nodes/expressions/BooleanExpression.java

@@ -0,0 +1,16 @@
+package de.hsrm.compiler.Klang.nodes.expressions;
+
+import de.hsrm.compiler.Klang.visitors.Visitor;
+
+public class BooleanExpression extends Expression {
+    public boolean value;
+
+    public BooleanExpression(boolean value) {
+        this.value = value;
+    }
+
+    @Override
+    public <R> R welcome(Visitor<R> v) {
+        return v.visit(this);
+    }
+}

src/main/java/de/hsrm/compiler/Klang/types/BooleanType.java

@@ -0,0 +1,20 @@
+package de.hsrm.compiler.Klang.types;
+
+public class BooleanType extends PrimitiveType {
+
+  private static BooleanType instance = null;
+
+  public static BooleanType getType() {
+    if (instance != null) {
+      return instance;
+    }
+    instance = new BooleanType();
+    return instance;
+  }
+
+  @Override
+  public boolean isBooleanType() {
+    return true;
+  }
+
+}

src/main/java/de/hsrm/compiler/Klang/types/PrimitiveType.java

@@ -10,4 +10,8 @@ public abstract class PrimitiveType extends Type {
   public boolean isIntegerType() {
     return false;
   };
+
+  public boolean isBooleanType() {
+    return false;
+  };
 }

src/main/java/de/hsrm/compiler/Klang/types/Type.java

@@ -8,5 +8,9 @@ public abstract class Type {
     return IntegerType.getType();
   }
 
+  public static BooleanType getBooleanType() {
+    return BooleanType.getType();
+  }
+
   public abstract boolean isPrimitiveType();
 }

src/main/java/de/hsrm/compiler/Klang/visitors/EvalVisitor.java

@@ -23,6 +23,11 @@ public class EvalVisitor implements Visitor<Value> {
     return new Value(e.value);
   }
 
+  @Override
+  public Value visit(BooleanExpression e) {
+    return new Value(e.value);
+  }
+
   @Override
   public Value visit(EqualityExpression e) {
     Value lhs = e.lhs.welcome(this);

src/main/java/de/hsrm/compiler/Klang/visitors/GenASM.java

@@ -78,6 +78,12 @@ public class GenASM implements Visitor<Void> {
     return null;
   }
 
+  @Override
+  public Void visit(BooleanExpression e) {
+    this.ex.write("    movq $" + (e.value ? 1 : 0) + ", %rax\n");
+    return null;
+  }
+
   @Override
   public Void visit(Variable e) {
     this.ex.write("    movq " + this.env.get(e.name) + "(%rbp), %rax\n");
@@ -324,7 +330,7 @@ public class GenASM implements Visitor<Void> {
     this.ex.write("    jnz .L" + lblStart + "\n");
     return null;
   }
-  
+
   @Override
   public Void visit(ForLoop e) {
     int lblStart = ++lCount;
@@ -338,7 +344,7 @@ public class GenASM implements Visitor<Void> {
     e.step.welcome(this);
     this.ex.write("    jmp .L" + lblStart + "\n");
     this.ex.write(".L" + lblEnd + ":\n");
-        
+
     return null;
   }
 
@@ -453,7 +459,7 @@ public class GenASM implements Visitor<Void> {
       this.ex.write("\n");
     }
     this.ex.write(".globl " + mainName + "\n");
-    this.ex.write(".type " +mainName + ", @function\n");
+    this.ex.write(".type " + mainName + ", @function\n");
     this.ex.write(mainName + ":\n");
     this.ex.write("    pushq %rbp\n");
     this.ex.write("    movq %rsp, %rbp\n");

src/main/java/de/hsrm/compiler/Klang/visitors/GetVars.java

@@ -22,6 +22,11 @@ class GetVars implements Visitor<Void> {
     return null;
   }
 
+  @Override
+  public Void visit(BooleanExpression e) {
+    return null;
+  }
+
   @Override
   public Void visit(Variable e) {
     return null;

src/main/java/de/hsrm/compiler/Klang/visitors/PrettyPrintVisitor.java

@@ -72,6 +72,12 @@ public class PrettyPrintVisitor implements Visitor<Void> {
     return null;
   }
 
+  @Override
+  public Void visit(BooleanExpression e) {
+    ex.write(e.value);
+    return null;
+  }
+
   @Override
   public Void visit(EqualityExpression e) {
     ex.write("(");

src/main/java/de/hsrm/compiler/Klang/visitors/Visitor.java

@@ -9,6 +9,7 @@ import de.hsrm.compiler.Klang.nodes.statements.*;
 
 public interface Visitor<R> {
     R visit(IntegerExpression e);
+    R visit(BooleanExpression e);
     R visit(Variable e);
     R visit(AdditionExpression e);
     R visit(EqualityExpression e);