case CSR_MEPC: state.mepc = val; break;
case CSR_MTVEC: state.mtvec = val & ~(reg_t)2; break;
case CSR_MSCRATCH: state.mscratch = val; break;
case CSR_MCAUSE: state.mcause = val; break;
case CSR_MEPC: state.mepc = val; break;
case CSR_MTVEC: state.mtvec = val & ~(reg_t)2; break;
case CSR_MSCRATCH: state.mscratch = val; break;
case CSR_MCAUSE: state.mcause = val; break;