SW_R19 94 arch/nios2/include/asm/entry.h stw r19, SW_R19(sp) SW_R19 108 arch/nios2/include/asm/entry.h ldw r19, SW_R19(sp) SW_R19 57 arch/nios2/kernel/asm-offsets.c OFFSET(SW_R19, switch_stack, r19);