Re: My view on this "Is blah an assembler"

From: Herbert Kleebauer (klee_at_unibwm.de)
Date: 08/16/04 

Date: Mon, 16 Aug 2004 21:41:02 +0200

C wrote:
 
> add ax, bx -> add.w a, b
> mov ax, bx -> mov.w a, b
> mov cs, dx -> mov.sw c, d

ax -> a bx -> b cx -> c dx -> d
bp -> ? si -> ? di -> ? sp -> ?
ah -> ? bh -> ? ch -> ? dh -> ?

Wouldn't it be better to number the registers (r0 - r7) instead
of using different single letter names?

> movzx eax, bl -> mov.db a, b

    movsx eax, bl -> ?

This instructions are not simple move instruction and
therefore deserve an own opcode: movs.bd movs.bw movs.wd
                                 muvu.bd movs.bw movs.wd

> movsb -> mov.ab

What is .ab? It is a simple byte move with register indirect
addressing with auto postincrement (postdecrement).

mov.b (r5)+,(r6)+
mov.b (r5)-,(r6)-

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