Merge pull request #65 from GilbertBckr/while

added codegen for (do) while

Author: MarkusEble

src/main/java/com/compiler/ast/ASTDoWhileLoopStmtNode.java

@@ -2,6 +2,11 @@
 
 import java.io.OutputStreamWriter;
 
+import com.compiler.CompileEnvIntf;
+import com.compiler.InstrBlock;
+import com.compiler.instr.InstrCondJump;
+import com.compiler.instr.InstrJump;
+
 public class ASTDoWhileLoopStmtNode extends ASTStmtNode {
 
     ASTExprNode m_predicate;
@@ -26,4 +31,20 @@ public void print(OutputStreamWriter outStream, String indent) throws Exception
         m_predicate.print(outStream, "  " + indent);
         m_loopBody.print(outStream, "  " + indent);
     }
+
+    @Override
+    public void codegen(CompileEnvIntf env) {
+        InstrBlock doWhile = env.createBlock("DoWhileBlock");
+        InstrBlock exit = env.createBlock("DoWhileExitBlock");
+
+        InstrJump jumpToLoop = new InstrJump(doWhile);
+        env.addInstr(jumpToLoop);
+
+        env.setCurrentBlock(doWhile);
+        m_loopBody.codegen(env);
+        InstrCondJump conditionalJump = new InstrCondJump(m_predicate.codegen(env), doWhile, exit);
+        env.addInstr(conditionalJump);
+
+        env.setCurrentBlock(exit);
+    }
 }

src/main/java/com/compiler/ast/ASTWhileLoopStmtNode.java

@@ -2,6 +2,11 @@
 
 import java.io.OutputStreamWriter;
 
+import com.compiler.CompileEnvIntf;
+import com.compiler.InstrBlock;
+import com.compiler.instr.InstrCondJump;
+import com.compiler.instr.InstrJump;
+
 public class ASTWhileLoopStmtNode extends ASTStmtNode {
 
     ASTExprNode m_predicate;
@@ -26,4 +31,26 @@ public void print(OutputStreamWriter outStream, String indent) throws Exception
         m_predicate.print(outStream, "  " + indent);
         m_loopBody.print(outStream, "  " + indent);
     }
+
+    @Override
+    public void codegen(CompileEnvIntf env) {
+        InstrBlock whileHead = env.createBlock("WhileLoopHead");
+        InstrBlock whileBody = env.createBlock("WhileLoopBody");
+        InstrBlock exit = env.createBlock("WhileExitBlock");
+        InstrJump jumpToHead = new InstrJump(whileHead);
+        env.addInstr(jumpToHead);
+
+        env.setCurrentBlock(whileBody);
+
+        m_loopBody.codegen(env);
+
+        env.addInstr(new InstrJump(whileHead));
+
+        env.setCurrentBlock(whileHead);
+        InstrCondJump conditionalJump = new InstrCondJump(m_predicate.codegen(env), whileBody, exit);
+
+        whileHead.addInstr(conditionalJump);
+
+        env.setCurrentBlock(exit);
+    }
 }

src/test/java/com/compiler/StmtDoWhileStmtParserTest.java

@@ -2,65 +2,87 @@
 
 import org.junit.Test;
 
-public class StmtDoWhileStmtParserTest extends StmtParserTestBase
-{
-    @Test
-    public void testWhileProgram1() throws Exception {
-        String program = """
-            {
-              DECLARE index;
-              DECLARE sum;
-              index = 10;
-              sum = 0;
-              WHILE(index) {
-                sum = sum + index;
-                index = index - 1;
-              };
-              PRINT sum;
-            }
-            """;
-        // laut kleinem Gauß: 55
-        testParser(program, "55\n");
-    }
+public class StmtDoWhileStmtParserTest extends InterpreterTestBase {
+  @Test
+  public void testWhileProgram1() throws Exception {
+    String program = """
+        {
+          DECLARE index;
+          DECLARE sum;
+          index = 10;
+          sum = 0;
+          WHILE(index) {
+            sum = sum + index;
+            index = index - 1;
+          };
+          PRINT sum;
+        }
+        """;
+    // laut kleinem Gauß: 55
+    testInterpreter(program, "55\n");
+  }
 
-    @Test
-    public void testDoWhileProgram2() throws Exception {
-        String program = """
-            {
-              DECLARE index;
-              DECLARE sum;
-              index = 10;
-              sum = 0;
-              DO {
-                sum = sum + index;
-                index = index - 1;
-              } WHILE(index);
-              PRINT sum;
-            }
-            """;
-        testParser(program, "55\n");
-    }
+  @Test
+  public void testDoWhileProgram2() throws Exception {
+    String program = """
+        {
+          DECLARE index;
+          DECLARE sum;
+          index = 10;
+          sum = 0;
+          DO {
+            sum = sum + index;
+            index = index - 1;
+          } WHILE(index);
+          PRINT sum;
+        }
+        """;
+    testInterpreter(program, "55\n");
+  }
 
-    @Test
-    public void testNestedWhileProgram3() throws Exception {
-        String program = """
-            {
-              DECLARE index0;
-              DECLARE sum;
-              DECLARE index1;
-              index0 = 10;
-              sum = 0;
-              WHILE(index0) {
-                index1 = 5;
-                WHILE(index1) {
-                  sum = sum + index1;
-                  index1 = index1 - 1;
-                };
-                index0 = index0 - 1;
-              };
-              PRINT sum;
-            }
-            """;
-        testParser(program, "150\n");
-    }
+  @Test
+  public void testNestedWhileProgram3() throws Exception {
+    String program = """
+        {
+          DECLARE index0;
+          DECLARE sum;
+          DECLARE index1;
+          index0 = 10;
+          sum = 0;
+          WHILE(index0) {
+            index1 = 5;
+            WHILE(index1) {
+              sum = sum + index1;
+              index1 = index1 - 1;
+            };
+            index0 = index0 - 1;
+          };
+          PRINT sum;
+        }
+        """;
+    testInterpreter(program, "150\n");
+  }
+
+  @Test
+  public void testNestedDoWhileProgram4() throws Exception {
+    String program = """
+        {
+          DECLARE index0;
+          DECLARE sum;
+          DECLARE index1;
+          index0 = 10;
+          sum = 0;
+          DO {
+            index1 = 5;
+            DO {
+              sum = sum + index1;
+              index1 = index1 - 1;
+            } WHILE(index1);
+            index0 = index0 - 1;
+          } WHILE(index0) ;
+          PRINT sum;
+        }
+        """;
+    testInterpreter(program, "150\n");
+  }
 }