+Fri Jan 29 00:14:55 1999 J"orn Rennecke <amylaar@cygnus.co.uk>
+
+ * loop.c (strength_reduce): Grow set_in_loop / n_times_set /
+ may_not_optimize to proper size when converting biv increments
+ into givs.
+ If necessary, reallocate reg_iv_type / reg_iv_info before calling
+ recombine_givs.
+
Thu Jan 28 23:24:08 1999 J"orn Rennecke <amylaar@cygnus.co.uk>
* loop.c (recombine_givs): New parameter unroll_p. If set, don't
old_reg = v->dest_reg;
dest_reg = gen_reg_rtx (v->mode);
+ /* Unlike reg_iv_type / reg_iv_info, the other three arrays
+ have been allocated with some slop space, so we may not
+ actually need to reallocate them. If we do, the following
+ if statement will be executed just once in this loop. */
if ((unsigned) max_reg_num () > n_times_set->num_elements)
{
- int nregs = max_reg_before_loop + n_extra_increment;
-
- /* Grow all the arrays. */
+ /* Grow all the remaining arrays. */
VARRAY_GROW (set_in_loop, nregs);
VARRAY_GROW (n_times_set, nregs);
VARRAY_GROW (may_not_optimize, nregs);
int benefit;
int all_reduced;
rtx final_value = 0;
+ unsigned nregs;
/* Test whether it will be possible to eliminate this biv
provided all givs are reduced. This is possible if either
}
/* Now that we know which givs will be reduced, try to rearrange the
- combinations to reduce register pressure. */
+ combinations to reduce register pressure.
+ recombine_givs calls find_life_end, which needs reg_iv_type and
+ reg_iv_info to be valid for all pseudos. We do the necessary
+ reallocation here since it allows to check if there are still
+ more bivs to process. */
+ nregs = max_reg_num ();
+ if (nregs > reg_iv_type->num_elements)
+ {
+ /* If there are still more bivs to process, allocate some slack
+ space so that we're not constantly reallocating these arrays. */
+ if (bl->next)
+ nregs += nregs / 4;
+ /* Reallocate reg_iv_type and reg_iv_info. */
+ VARRAY_GROW (reg_iv_type, nregs);
+ VARRAY_GROW (reg_iv_info, nregs);
+ }
recombine_givs (bl, loop_start, loop_end, unroll_p);
/* Reduce each giv that we decided to reduce. */