GDB_R0 17 arch/nios2/include/asm/kgdb.h GDB_R0 = 0, GDB_R0 9 arch/sh/include/asm/kgdb.h GDB_R0, GDB_R1, GDB_R2, GDB_R3, GDB_R4, GDB_R5, GDB_R6, GDB_R7,