static void
abstract_best_seq (void)
{
pattern_seq bestpseq;
/* Do the abstraction. */
determine_seq_blocks ();
split_blocks_after_seqs ();
split_pattern_seq ();
erase_matching_seqs ();
free_seq_blocks ();
/* Record the usage of the link register. */
df_set_regs_ever_live (REGNO (pattern_seqs->link_reg), true);
/* Remove the best pattern sequence. */
bestpseq = pattern_seqs;
pattern_seqs = bestpseq->next_pattern_seq;
free_pattern_seq (bestpseq);
}
static bool
rename_single_chain (du_head_p head, HARD_REG_SET *unavailable)
{
int best_new_reg;
int n_uses = 0;
struct du_chain *tmp;
int reg = head->regno;
enum reg_class super_class = NO_REGS;
if (head->cannot_rename)
return false;
if (fixed_regs[reg] || global_regs[reg]
|| (frame_pointer_needed && reg == HARD_FRAME_POINTER_REGNUM))
return false;
/* Iterate over elements in the chain in order to:
1. Count number of uses, and narrow the set of registers we can
use for renaming.
2. Compute the superunion of register classes in this chain. */
for (tmp = head->first; tmp; tmp = tmp->next_use)
{
if (DEBUG_INSN_P (tmp->insn))
continue;
n_uses++;
IOR_COMPL_HARD_REG_SET (*unavailable, reg_class_contents[tmp->cl]);
super_class = reg_class_superunion[(int) super_class][(int) tmp->cl];
}
if (n_uses < 1)
return false;
best_new_reg = find_rename_reg (head, super_class, unavailable, reg,
false);
if (dump_file)
{
fprintf (dump_file, "Register %s in insn %d", reg_names[reg],
INSN_UID (head->first->insn));
if (head->need_caller_save_reg)
fprintf (dump_file, " crosses a call");
}
if (best_new_reg == reg)
{
if (dump_file)
fprintf (dump_file, "; no available better choice\n");
return false;
}
if (regrename_do_replace (head, best_new_reg))
{
if (dump_file)
fprintf (dump_file, ", renamed as %s\n", reg_names[best_new_reg]);
df_set_regs_ever_live (best_new_reg, true);
}
else
{
if (dump_file)
fprintf (dump_file, ", renaming as %s failed\n",
reg_names[best_new_reg]);
return false;
}
return true;
}
