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From: Lawrence D'Oliveiro <ldo@nz.invalid>
Newsgroups: comp.arch
Subject: Re: Why VAX Was the Ultimate CISC and Not RISC
Date: Wed, 12 Mar 2025 00:38:59 -0000 (UTC)
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On Wed, 12 Mar 2025 00:26:50 -0000 (UTC), John Levine wrote:

> Next was PDP=11 where MOV R1,R2 copies R1 into R2.

What about CMP (compare) versus SUB (subtract)? CMP does the subtract 
without updating the destination operand, only setting the condition 
codes. But are the operands the same way around as SUB (i.e. backwards for 
comparison purposes) or are they flipped?