public static void execute(ARM7TDMI cpu, MemoryInterface memory, int opcode) {
int rdIndex = (opcode >>> 8) & 0x0007;
int spValue = cpu.getSP();
int offset = (opcode & 0x00FF) << 2;
if ((opcode & 0x0800) == 0) { // STR Rd, [SP, #nn]
memory.storeWord(spValue + offset, cpu.getRegister(rdIndex));
} else { // LDR Rd, [SP, #nn]
cpu.setRegister(rdIndex, memory.loadWord(spValue + offset));
}
}
public static String disassemble(ARM7TDMI cpu, MemoryInterface memory, int opcode, int offset) {
int instruction = (opcode >>> 11) & 0x0001;
String rd = cpu.getRegisterName((opcode >>> 8) & 0x0007);
String sp = cpu.getRegisterName(13);
int off = (opcode & 0x00FF) << 2;
return InstructionName[instruction]
+ " "
+ rd
+ ", ["
+ sp
+ ", "
+ Hex.toHexString(off, Hex.Bit_12)
+ "]";
}
public static void execute(ARM7TDMI cpu, MemoryInterface memory, int opcode) {
boolean condition;
switch (opcode & 0x0F00) {
case 0x0000: // BEQ label
condition = cpu.getZFlag();
break;
case 0x0100: // BNE label
condition = !cpu.getZFlag();
break;
case 0x0200: // BCS label
condition = cpu.getCFlag();
break;
case 0x0300: // BCC label
condition = !cpu.getCFlag();
break;
case 0x0400: // BMI label
condition = cpu.getNFlag();
break;
case 0x0500: // BPL label
condition = !cpu.getNFlag();
break;
case 0x0600: // BVS label
condition = cpu.getVFlag();
break;
case 0x0700: // BVC label
condition = !cpu.getVFlag();
break;
case 0x0800: // BHI label
condition = (cpu.getCFlag() && !cpu.getZFlag());
break;
case 0x0900: // BLS label
condition = (!cpu.getCFlag() || cpu.getZFlag());
break;
case 0x0A00: // BGE label
condition = (cpu.getNFlag() == cpu.getVFlag());
break;
case 0x0B00: // BLT label
condition = (cpu.getNFlag() != cpu.getVFlag());
break;
case 0x0C00: // BGT label
condition = (!cpu.getZFlag() && (cpu.getNFlag() == cpu.getVFlag()));
break;
case 0x0D00: // BLE label
condition = (cpu.getZFlag() || (cpu.getNFlag() != cpu.getVFlag()));
break;
default: // Unknown
condition = false;
}
if (condition) {
int offset = ((byte) (opcode & 0x00FF)) << 1;
cpu.setPC(cpu.getPC() + offset);
cpu.flushTHUMBPipeline();
}
}