🚀 go-pugleaf

mykes@amiga0.SF-Bay.ORG (Mike Schwartz) writes:

>Make 'em faint every 5 minutes! :)  How fortunate that goto maps to an
>instruction that is available on every CPU (or variant of the
>instruction): jmp, bra, jr, etc.  To ignore goto is like burying your
>head in the sand.  


Using unstructured branches (gotos) ruins optimisability.


Time this code:

	main()
	{
	  int i;

	#ifdef STRUCTURED
	  for (i=0; i<3000000; i++);
	#else
	  i=0;
	y:
	  if (i>=3000000) goto x;
	  i++;
	  goto y;

	x:;
	#endif
	}

using each of these:
	cc foo.c
	cc -DSTRUCTURED foo.c
	cc -O foo.c
	cc -O -DSTRUCTURED foo.c


--
Warwick
--
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 \_.-._/     University of Queensland,    /      void (if removed)
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