Bug fix

Author: dibyendumajumdar

optvm/src/main/java/com/compilerprogramming/ezlang/interpreter/Interpreter.java

@@ -108,13 +108,13 @@ else if (cbrInst.condition() instanceof Operand.ConstantOperand constantOperand)
                     int reg = baseReg;
                     for (Operand arg: callInst.args()) {
                         if (arg instanceof Operand.RegisterOperand param) {
-                            execStack.stack[base + reg] = execStack.stack[base + param.frameSlot()];
+                            execStack.stack[reg] = execStack.stack[base + param.frameSlot()];
                         }
                         else if (arg instanceof Operand.ConstantOperand constantOperand) {
-                            execStack.stack[base + reg] = new Value.IntegerValue(constantOperand.value);
+                            execStack.stack[reg] = new Value.IntegerValue(constantOperand.value);
                         }
                         else if (arg instanceof Operand.NullConstantOperand) {
-                            execStack.stack[base + reg] = new Value.NullValue();
+                            execStack.stack[reg] = new Value.NullValue();
                         }
                         reg += 1;
                     }
@@ -193,7 +193,7 @@ else if (binaryInst.right() instanceof Operand.RegisterOperand registerOperand)
                             case "<": value = x < y ? 1: 0; break;
                             case ">": value = x > y ? 1 : 0; break;
                             case "<=": value = x <= y ? 1 : 0; break;
-                            case ">=": value = x <= y ? 1 : 0; break;
+                            case ">=": value = x >= y ? 1 : 0; break;
                             default: throw new IllegalStateException();
                         }
                         execStack.stack[base + binaryInst.result().frameSlot()] = new Value.IntegerValue(value);

registervm/src/main/java/com/compilerprogramming/ezlang/interpreter/Interpreter.java

@@ -108,13 +108,13 @@ else if (cbrInst.condition() instanceof Operand.ConstantOperand constantOperand)
                     int reg = baseReg;
                     for (Operand arg: callInst.args()) {
                         if (arg instanceof Operand.RegisterOperand param) {
-                            execStack.stack[base + reg] = execStack.stack[base + param.frameSlot()];
+                            execStack.stack[reg] = execStack.stack[base + param.frameSlot()];
                         }
                         else if (arg instanceof Operand.ConstantOperand constantOperand) {
-                            execStack.stack[base + reg] = new Value.IntegerValue(constantOperand.value);
+                            execStack.stack[reg] = new Value.IntegerValue(constantOperand.value);
                         }
                         else if (arg instanceof Operand.NullConstantOperand) {
-                            execStack.stack[base + reg] = new Value.NullValue();
+                            execStack.stack[reg] = new Value.NullValue();
                         }
                         reg += 1;
                     }
@@ -193,7 +193,7 @@ else if (binaryInst.right() instanceof Operand.RegisterOperand registerOperand)
                             case "<": value = x < y ? 1: 0; break;
                             case ">": value = x > y ? 1 : 0; break;
                             case "<=": value = x <= y ? 1 : 0; break;
-                            case ">=": value = x <= y ? 1 : 0; break;
+                            case ">=": value = x >= y ? 1 : 0; break;
                             default: throw new IllegalStateException();
                         }
                         execStack.stack[base + binaryInst.result().frameSlot()] = new Value.IntegerValue(value);

registervm/src/test/java/com/compilerprogramming/ezlang/interpreter/TestInterpreter.java

@@ -244,4 +244,92 @@ func foo()->Int
         Assert.assertTrue(value instanceof Value.IntegerValue integerValue &&
                 integerValue.value == 1);
     }
+
+        @Test
+    public void testMergeSort() {
+        String src = """
+// based on the top-down version from https://en.wikipedia.org/wiki/Merge_sort
+// via https://github.com/SeaOfNodes/Simple
+func merge_sort(a: [Int], b: [int], n: Int) 
+{
+    copy_array(a, 0, n, b)
+    split_merge(a, 0, n, b)
+}
+
+func split_merge(b: [Int], begin: Int, end: Int, a: [Int])
+{
+    if (end - begin <= 1)
+        return;
+    var middle = (end + begin) / 2
+    split_merge(a, begin, middle, b)
+    split_merge(a, middle, end, b)
+    merge(b, begin, middle, end, a)
+}
+
+func merge(b: [Int], begin: Int, middle: Int, end: Int, a: [Int])
+{
+    var i = begin
+    var j = middle
+    var k = begin
+    while (k < end) {
+        // && and ||
+        var cond = 0
+        if (i < middle) {
+            if (j >= end)          cond = 1;
+            else if (a[i] <= a[j]) cond = 1;
+        }
+        if (cond)
+        {
+            b[k] = a[i]
+            i = i + 1
+        }
+        else
+        {
+            b[k] = a[j]
+            j = j + 1
+        }
+        k = k + 1
+    }
+}
+
+func copy_array(a: [Int], begin: Int, end: Int, b: [Int])
+{
+    var k = begin
+    while (k < end)
+    {
+        b[k] = a[k]
+        k = k + 1
+    }
+}
+
+func eq(a: [Int], b: [Int], n: Int)->Int
+{
+    var result = 1
+    var i = 0
+    while (i < n)
+    {
+        if (a[i] != b[i])
+        {
+            result = 0
+            break
+        }
+        i = i + 1
+    } 
+    return result
+}
+
+func main()->Int
+{
+    var a = new [Int]{10,9,8,7,6,5,4,3,2,1}
+    var b = new [Int]{ 0,0,0,0,0,0,0,0,0,0}
+    var expect = new [Int]{1,2,3,4,5,6,7,8,9,10}
+    merge_sort(a, b, 10)
+    return eq(a,expect,10)
+}
+""";
+        var value = compileAndRun(src, "main");
+        Assert.assertNotNull(value);
+        Assert.assertTrue(value instanceof Value.IntegerValue integerValue &&
+                integerValue.value == 1);
+    }
 }