chris@mimsy.UUCP (Chris Torek) (12/18/88)
In article <771@quintus.UUCP> ok@quintus.uucp (Richard A. O'Keefe) writes: >... the VAX has an EDIV instruction, but it is awkward to set up. The 4.1BSD >C compiler would generate the equivalent of x-(x/y)*y for x%y. For those >with SPARCs, a look at the code generated for x%y might be illuminating. It still does. EDIV is not just hard to use (actually, it is `just not hard to use'---it needs register pairs, but double precision needs register pairs too, so that code already exists). EDIV is *slow*. t=x-(x/y)*y is considerably faster than EDIV x,y,trash,t. -- In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7163) Domain: chris@mimsy.umd.edu Path: uunet!mimsy!chris