52 lines
842 B
NASM
52 lines
842 B
NASM
;;; factorial.asm: A program that generates the factorials of each
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;;; number from 1 to 22 (22!~=UINT64_MAX). Using the registers to
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;;; store `n` and `n!`.
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;; Constants
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%const(limit) 22 %end
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;; Setup entrypoint
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global main
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main:
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;; $I -> W[0] = 1, $J -> W[1] = 1
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push.word 1
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mov.word 0
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push.word 1
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mov.word 1
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;; Print `$I: $J`
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loopback:
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push.byte '\t'
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print.char
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push.reg.word 0
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print.word
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push.byte ':'
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print.char
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push.byte ' '
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print.char
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push.reg.word 1
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print.word
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push.byte '\n'
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print.char
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;; $I += 1
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push.reg.word 0
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push.word 1
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plus.word
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mov.word 0
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;; $J *= $I
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push.reg.word 0
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push.reg.word 1
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mult.word
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mov.word 1
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;; IF $I >= $LIMIT ...
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push.word $limit
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push.reg.word 0
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gte.word
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;; THEN jump to `loopback`
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jump.if.byte loopback
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;; ELSE halt
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halt
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