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Re: copyprop_hardreg_forward removes division
> Lars Brinkhoff <firstname.lastname@example.org> writes:
> > Jan Hubicka <email@example.com> writes:
> > > Lars Brinkhoff wrote:
> > > > I have a problem with a dissapearing division instruction.
> > > It looks like you are having same problem as I had. copyprop_hardreg misses
> > > the stores to subregs. I've commited fix to that so hope it is OK in the
> > > tree (see kill_value).
> > No. I'm using the trunk of the tree, updated yesterday, and your
> > patch seems to be there
> kill_set_value is called with the SUBREGs, so I need something like
> this, or else kill_set_value will never call kill_value. However,
> this duplicates what your patch did to kill_value, so maybe we can
> just change "REG_P(x)" to "(REG_P (x) || GET_CODE (x) == SUBREG)"
> or something.S
> What do you think? I'll make a fully tested patch when I know what
> the best solution is.
I guess this is not complettely valid. We are setting the subreg, not the
reg itself. Safe fix would be to call kill_value outside the if block.
I will send patch shortly.
> *************** kill_set_value (x, set, data)
> *** 1186,1191 ****
> --- 1186,1195 ----
> void *data;
> struct value_data *vd = data;
> + if (GET_CODE (x) == SUBREG)
> + x = simplify_subreg (GET_MODE (x), SUBREG_REG (x),
> + GET_MODE (SUBREG_REG (x)), SUBREG_BYTE (x));
> if (GET_CODE (set) != CLOBBER && REG_P (x))
> kill_value (x, vd);
> Lars Brinkhoff http://lars.nocrew.org/ Linux, GCC, PDP-10,
> Brinkhoff Consulting http://www.brinkhoff.se/ HTTP programming