diff --git a/src/main/java/org/jcnc/snow/vm/commands/bitwise/short16/SAndCommand.java b/src/main/java/org/jcnc/snow/vm/commands/bitwise/short16/SAndCommand.java new file mode 100644 index 0000000..ea308f5 --- /dev/null +++ b/src/main/java/org/jcnc/snow/vm/commands/bitwise/short16/SAndCommand.java @@ -0,0 +1,56 @@ +package org.jcnc.snow.vm.commands.bitwise.short16; + +import org.jcnc.snow.vm.interfaces.Command; +import org.jcnc.snow.vm.module.CallStack; +import org.jcnc.snow.vm.module.LocalVariableStore; +import org.jcnc.snow.vm.module.OperandStack; + +/** + * The SAndCommand class implements the {@link Command} interface and represents the short16 bitwise AND (`&`) operation command. + * This class performs a short16 bitwise AND operation in the virtual machine by popping the top two values from the stack, + * computing their short16 bitwise AND operation, and then pushing the result back onto the stack. It is a basic operation command within the virtual machine. + * + *

Specific behavior:

+ * + */ +public class SAndCommand implements Command { + /** + * Default constructor for creating an instance of {@code SAndCommand}. + * This constructor is empty as no specific initialization is required. + */ + public SAndCommand() { + // Empty constructor + } + + /** + * Executes the virtual machine instruction's operation. + * + * @param parts The array of instruction parameters, which usually includes the operator and related arguments. + * @param currentPC The current program counter-value, indicating the address of the instruction being executed. + * @param operandStack The virtual machine's operand stack manager, responsible for pushing and popping values. + * @param localVariableStore The local variable store, typically used to manage method-local variables. + * @param callStack The virtual machine's call stack, used for managing method calls and returns. + * @return The updated program counter-value, typically `currentPC + 1` unless a control flow instruction is executed. + * @throws IllegalStateException if there are not enough operands on the stack to perform the operation. + */ + @Override + public int execute(String[] parts, int currentPC, OperandStack operandStack, LocalVariableStore localVariableStore, CallStack callStack) { + // Ensure the stack has at least two operands + if (operandStack.size() < 2) { + throw new IllegalStateException("Not enough operands on the stack for SAND operation."); + } + + // Pop the top two operands from the stack + final short b = (short) operandStack.pop(); + final short a = (short) operandStack.pop(); + + // Perform the short16 bitwise AND operation and push the result back onto the stack + operandStack.push(a & b); + + return currentPC + 1; + } +}