Moving floating point values around

Chris Torek chris at mimsy.UUCP
Tue Aug 23 23:05:44 AEST 1988


In article <4256 at lynx.UUCP> m5 at lynx.UUCP (Mike McNally) writes:
>How naughty would it be for a compiler for the 386/387 (or 286/287 for that
>matter) to move floating-point values with 386 MOV instructions instead
>of FLD and FSTP?

Probably safe: the 4.3BSD C compiler (actually, peephole optimiser)
can be told to change movf and movd instructions to movl and movq
(`/lib/c2 -f').  This is used by the f77 compiler; it improves some
benchmarks rather surprisingly.
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7163)
Domain:	chris at mimsy.umd.edu	Path:	uunet!mimsy!chris



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