62 строки
747 B
ArmAsm
62 строки
747 B
ArmAsm
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/* memset.S */
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#include <asm/linkage.h>
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#if defined(__H8300H__)
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.h8300h
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#endif
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#if defined(__H8300S__)
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.h8300s
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#endif
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.text
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.global SYMBOL_NAME(memset)
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;;void *memset(*ptr, int c, size_t count)
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;; ptr = er0
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;; c = er1(r1l)
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;; count = er2
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SYMBOL_NAME_LABEL(memset)
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btst #0,r0l
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beq 2f
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;; odd address
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1:
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mov.b r1l,@er0
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adds #1,er0
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dec.l #1,er2
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beq 6f
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;; even address
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2:
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mov.l er2,er3
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cmp.l #4,er2
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blo 4f
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;; count>=4 -> count/4
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#if defined(__H8300H__)
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shlr.l er2
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shlr.l er2
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#endif
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#if defined(__H8300S__)
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shlr.l #2,er2
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#endif
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;; byte -> long
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mov.b r1l,r1h
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mov.w r1,e1
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3:
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mov.l er1,@er0
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adds #4,er0
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dec.l #1,er2
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bne 3b
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4:
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;; count % 4
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and.b #3,r3l
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beq 6f
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5:
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mov.b r1l,@er0
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adds #1,er0
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dec.b r3l
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bne 5b
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6:
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rts
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