Usage of refTable in gc / declaration of VALIDREF

[Frank Mehnert]

Hi,

the gc of kaffe uses a refTable to index each object. In function
scanConservative each object is scanned to find any references to other
objects. The macro VALIDREF tests if a reference is valid (declared in
gc-incremental.h):

#define	VALIDREF(_r)					\
		((_r) / REF_MAXW < REF_MAXH &&		\
		refTable.width[(_r) / REF_MAXW] != 0)

But there is NOT a line refTable.width[0]!!! Compare function gc_malloc
for this:

	refTable.nextWidth++;
	assert(refTable.nextWidth < REF_MAXH);
	refTable.width[refTable.nextWidth] =
				checked_calloc(REF_MAXW, sizeof(uintp));


So let us change the declaration of VALIDREF into

#define	VALIDREF(_r)						\
		(((_r)-REF_MAXH) / REF_MAXW < (REF_MAXH-1) &&	\
		refTable.width[(_r) / REF_MAXW] != 0)

Do you agree with that?

Because of linebreaks I have uuencoded the patch:

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end


Frank

Frank Mehnert
email: Frank.Mehnert at mchp.siemens.de