Re: RISC vs CISC Re: Intel 8086 opcodes

no.spam@xxxxxxxxxxxxxxxxxxxxxxx wrote:
[...]
Total number of instructions is not a definate criteria. USually RISC
designs were more biased by simple archetectures that were very fast
(for there time) that executed simple instructions in or or two clock
cycles max. SPARC, ARM are RISC examples and 8086, 6809, 68000,
PSP11 and VAX are examples of CISC.

OTOH the PowerPC, which is marketed as RISC, has about 300 instructions, more
than the uncontroversially CISC 8080 and 6502; and while the 68000 is CISC,
the Coldfire, which uses *exactly the same instruction set* [1], is RISC!

These days I reckon that modern processor design has taken on board the good
features of both the classic RISC *and* CISC designs, and as a result the
terms don't mean much any more.



[1] Okay, okay, not quite exactly. The Coldfire actually uses a subset of the
68000 opcodes. However, it's such a large subset that people have been
building binary-compatible Amiga clones using Coldfire processors. I have no
idea how *anyone* can consider these things RISC.

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