34 lines
676 B
ArmAsm
34 lines
676 B
ArmAsm
.altmacro
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.macro SAVE_SN n
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sd s\n, (\n+2)*8(a0)
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.endm
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.macro LOAD_SN n
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ld s\n, (\n+2)*8(a1)
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.endm
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.section .text
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.globl __switch
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__switch:
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# __switch(
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# current_task_cx_ptr: *mut TaskContext,
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# next_task_cx_ptr: *const TaskContext
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# )
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# save kernel stack of current task
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sd sp, 8(a0)
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# save ra & s0~s11 of current execution
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sd ra, 0(a0)
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.set n, 0
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.rept 12
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SAVE_SN %n
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.set n, n + 1
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.endr
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# restore ra & s0~s11 of next execution
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ld ra, 0(a1)
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.set n, 0
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.rept 12
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LOAD_SN %n
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.set n, n + 1
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.endr
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# restore kernel stack of next task
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ld sp, 8(a1)
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ret
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