Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!tut.cis.ohio-state.edu!ucbvax!hplabs!pyramid!csg From: csg@pyramid.pyramid.com (Carl S. Gutekunst) Newsgroups: comp.sys.pyramid Subject: Re: XP systems? Message-ID: <92827@pyramid.pyramid.com> Date: 29 Nov 89 05:02:30 GMT References: Reply-To: csg@pyramid.pyramid.com (Carl S. Gutekunst) Distribution: comp Organization: Pyramid Technology Corp., Mountain View, CA Lines: 19 >Are there any XP systems out there? Sure. That's the MIServer CPU. >I consider doing an extension to GCC to generate the three address >instructions, supported by these systems. Alas, these were dropped. It was one of those things that seemed like a pretty neat idea at the time, and the CPU people thought it would be trivial to add them to the new pipeline of the XP CPU. But a lot of people (including some of the compiler folks) weren't convinced they were that useful, and would have created binary incompatibility between the machines as well. When it appeared that release schedules might slip, work on the three operand instructions was quietly dropped. (Note that it was three *operand*, not three *address*.) There are some new instructions in the XP CPU, but they are applicable to the kernel only -- extending the architecture out to >8 CPUs, for example.