C optimizer
John Woods
john at frog.UUCP
Thu Feb 23 14:39:00 AEST 1989
In article <9648 at smoke.BRL.MIL>, gwyn at smoke.BRL.MIL (Doug Gwyn ) writes:
> Note also that ANSI C implementations can
> #define cos(x) __intrinsic_cos(x)
> or something along those lines, to allow the compiler to generate
> in-line code rather than an actual function call for standard
> functions. There actually is floating-point hardware with SQRT
> support; I don't know about COS.
The 68881 chip has FCOS, FSIN, and (gasp) FSINCOS which simultaneously
computes cos() and sin() of the same argument. A sufficiently clever
compiler could potentially make great use of that.
--
John Woods, Charles River Data Systems, Framingham MA, (508) 626-1101
...!decvax!frog!john, john at frog.UUCP, ...!mit-eddie!jfw, jfw at eddie.mit.edu
"He should be put in stocks in Lafeyette Square across from the White House
and pelted with dead cats." - George F. Will
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