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From: rmb@omews57.intel.com (Bob Bentley)
Newsgroups: comp.arch
Subject: Re: More on Linpack pivoting: isamax and instruction set design
Message-ID: <1991Jun14.183003.5669@ichips.intel.com>
Date: 14 Jun 91 18:30:03 GMT
References: <396@validgh.com> <1991Jun13.234834.22970@neon.Stanford.EDU> <1991Jun14.134338.4673@linus.mitre.org>
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In article <1991Jun14.134338.4673@linus.mitre.org> bs@frieda.mitre.org (Robert D. Silverman) writes:
> 
>I also have never seen a machine that has conditional assignment
>implemented as an instruction! ....... What machine is this?
>Could you show us the assembler syntax??
>

The Intel i960(tm) architecture has a limited type of conditional assignment
in the form of the TEST instructions, which are used to test the condition
code and set a boolean value in a register.  They are intended primarily
for implementing C statements of the form:

			a = b > c

without having to do conditional branches.  The assembler code might look like:

			cmpo  r5, r6
			testg r4

which causes r4 to be set to 0 or 1 depending on the result of the comparison.

See any 80960 Programmers Reference Manual or the Myers & Budde book for more
details.

	Bob Bentley
 	Intel Corp., M/S JF1-58			E-mail: rmb@ichips.intel.com 
 	5200 N.E. Elam Young Parkway		Phone:  (503) 696-4728          
 	Hillsboro, Oregon 97124			Fax:    (503) 696-4515