# MIPS32 诊断测试脚本
# 用于排查 ADD 指令不工作的问题

echo "========================================"
echo "  MIPS32 ADD 指令诊断测试"
echo "========================================"
echo ""

# 创建机器并加载平台
echo "【步骤 1】创建机器和加载平台"
mach create "MIPS-Diagnostic"
machine LoadPlatformDescription @platforms/cpus/mips32_simple.repl

# 显示CPU类型
echo "【步骤 2】验证 CPU 类型"
sysbus.cpu

# 设置初始状态
echo ""
echo "【步骤 3】设置初始状态"
cpu PC 0x80000000
cpu A0 5
cpu A1 3
cpu V0 0

# 显示设置后的寄存器
echo ""
echo "【步骤 4】验证初始寄存器值"
echo "  PC  ="
cpu PC
echo "  A0  ="
cpu A0
echo "  A1  ="
cpu A1
echo "  V0  ="
cpu V0

# 写入 ADD 指令：add $v0, $a0, $a1
echo ""
echo "【步骤 5】写入 ADD 指令到内存"
echo "  地址: 0x80000000"
echo "  指令: 0x00851020 (add v0, a0, a1)"
sysbus WriteDoubleWord 0x80000000 0x00851020

# 验证指令已写入
echo ""
echo "【步骤 6】验证指令已写入内存"
echo "  读取 0x80000000 ="
sysbus ReadDoubleWord 0x80000000

# 执行一条指令
echo ""
echo "【步骤 7】执行一条指令"
cpu Step 1

# 显示执行后的状态
echo ""
echo "【步骤 8】检查执行后的寄存器"
echo "  PC  ="
cpu PC
echo "  (预期: 0x80000004)"
echo ""
echo "  A0  ="
cpu A0
echo "  (预期: 0x5)"
echo ""
echo "  A1  ="
cpu A1
echo "  (预期: 0x3)"
echo ""
echo "  V0  ="
cpu V0
echo "  (预期: 0x8 = 5 + 3)"

echo ""
echo "========================================"
echo "  诊断结果分析"
echo "========================================"
echo "如果 V0 = 0x8 且 PC = 0x80000004:"
echo "  ✓ ADD 指令工作正常"
echo ""
echo "如果 V0 = 0x0:"
echo "  ✗ ADD 指令未执行或寄存器未更新"
echo ""
echo "如果 PC = 0x80000000:"
echo "  ✗ CPU 没有前进（指令未执行）"
echo "========================================"