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On Sat, 21 Oct 2006 13:36:04 -0400 |
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Jonathan Smith <smithj@g.o> wrote: |
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> ia64 is for itanium, which was |
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> intel's horrid first attempt at a 64-bit successor to x86. |
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I wouldn't call Itanium a successor to x86, any more than SPARC was |
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(recall that early Sun boxes were x86). As you mentioned, it's a |
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completely new architecture. |
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All those years people have been bashing Intel for the limitations of |
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x86 that have been retained for decades for compatibility |
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reasons (limited register set, nasty CISC, ever-increasing instruction |
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set) - they try to do the design-from-scratch thing and it just gets |
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ignored. AMD jump in and do what Intel had always previously done - |
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extend the existing architecture by bolting on extra stuff - and clean |
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up in the marketplace (or at least, hit Intel hard). |
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If you want to call any architecture horrid, I'd suggest x86, which |
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from a programmer's perspective has evolved into a real mess. x86_64 |
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alleviates some nastiness (register set is now workable, pc-relative |
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addressing is possible), but adds some more of its own. Of all the |
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processor architectures I've worked with, modern x86 is far and away |
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the muckiest from the point of view of an embedded software engineer. |
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-- |
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Kevin F. Quinn |
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