🚀 go-pugleaf

It appears that gcc doesn't optimize the following code as much as it
could in some cases:

	void foo (n) int *n; {
		int y;
		y = 0;
		y op= frep ();
		*n = y;
	}

where "op" is "*", "&", or "|"... it zeros a register (one which has
to be preserved around the function call) and uses it.  It does
properly fold things for "+" though.

I haven't checked with other identity or zero elements for other
operations (such as ~0 for '&' and '|').

I'm using version 1.32 on the vax, with optimization and
-fstrength-reduce and -fcombine-regs, though the same result is
produced with the two -f options turned off.

-- Ken