42 lines
572 B
NASM
42 lines
572 B
NASM
// This file is part of www.nand2tetris.org
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// and the book "The Elements of Computing Systems"
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// by Nisan and Schocken, MIT Press.
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// File name: projects/04/Mult.asm
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// Multiplies R0 and R1 and stores the result in R2.
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// (R0, R1, R2 refer to RAM[0], RAM[1], and RAM[2], respectively.)
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// R2 = 0
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@R2
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M = 0
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// i = 0
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@i
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M = 0
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(LOOP)
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// (if i >= R0 <=> if i - R0 >= 0) goto END
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@i
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D = M
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@R0
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D = D - M
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@END
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D;JGE
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// R2 = R2 + R1
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@R1
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D = M
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@R2
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M = M + D
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// i++
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@i
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M = M + 1
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// goto LOOP
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@LOOP
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0;JMP
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(END)
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@END
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0;JMP
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