guy@rlgvax.UUCP (Guy Harris) (10/11/84)
Here's the fix to the MIT 68000 C compiler to keep it from generating "movb"s
into address registers:
In "table.c", before the table entry that reads something like
ASSIGN, INAREG|FOREFF|FORCC,
EAA, TSCALAR|TFLOAT,
EA, TSCALAR|TFLOAT,
0, RLEFT|RRIGHT|RESCC,
" moveZB AR,AL\nT",
put an entry that reads like
ASSIGN, INAREG|FOREFF|FORCC,
EAA, TCHAR,
SBREG|STBREG, TCHAR,
NAREG|NASR, RLEFT|RRIGHT|RESCC,
" move.l AR,A1\n moveZB A1,AL\nT",
(your mileage and exact entries may differ). This entry forces a move of
a "char" into a "B register" (which is an address register) to proceed
first by moving the character into a scratch "A register" (data register)
and then move the data register into the address register.
This fix is thanks to somebody at MIT named, I believe, Jonathan something-
or-other, and was posted in response to an article from Steve Kramer mentioning
the bug. (Apologies to Jonathan X, but I don't have the article any more
and don't remember his name.)
Guy Harris
{seismo,ihnp4,allegra}!rlgvax!guy