/* Mark pseudo REGNO as living at program point POINT, update conflicting
hard registers of the pseudo and START_LIVING, and start a new live
range for the pseudo corresponding to REGNO if it is necessary. */
static void
mark_pseudo_live (int regno, int point)
{
lra_live_range_t p;
lra_assert (regno >= FIRST_PSEUDO_REGISTER);
lra_assert (! sparseset_bit_p (pseudos_live, regno));
sparseset_set_bit (pseudos_live, regno);
IOR_HARD_REG_SET (lra_reg_info[regno].conflict_hard_regs, hard_regs_live);
if ((complete_info_p || lra_get_regno_hard_regno (regno) < 0)
&& ((p = lra_reg_info[regno].live_ranges) == NULL
|| (p->finish != point && p->finish + 1 != point)))
lra_reg_info[regno].live_ranges
= create_live_range (regno, point, -1, p);
sparseset_set_bit (start_living, regno);
}
/* Spill pseudos which are assigned to hard registers in SET. Add
affected insns for processing in the subsequent constraint
pass. */
static void
spill_pseudos (HARD_REG_SET set)
{
int i;
bitmap_head to_process;
rtx_insn *insn;
if (hard_reg_set_empty_p (set))
return;
if (lra_dump_file != NULL)
{
fprintf (lra_dump_file, " Spilling non-eliminable hard regs:");
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
if (TEST_HARD_REG_BIT (set, i))
fprintf (lra_dump_file, " %d", i);
fprintf (lra_dump_file, "\n");
}
bitmap_initialize (&to_process, ®_obstack);
for (i = FIRST_PSEUDO_REGISTER; i < max_reg_num (); i++)
if (lra_reg_info[i].nrefs != 0 && reg_renumber[i] >= 0
&& overlaps_hard_reg_set_p (set,
PSEUDO_REGNO_MODE (i), reg_renumber[i]))
{
if (lra_dump_file != NULL)
fprintf (lra_dump_file, " Spilling r%d(%d)\n",
i, reg_renumber[i]);
reg_renumber[i] = -1;
bitmap_ior_into (&to_process, &lra_reg_info[i].insn_bitmap);
}
IOR_HARD_REG_SET (lra_no_alloc_regs, set);
for (insn = get_insns (); insn != NULL_RTX; insn = NEXT_INSN (insn))
if (bitmap_bit_p (&to_process, INSN_UID (insn)))
{
lra_push_insn (insn);
lra_set_used_insn_alternative (insn, -1);
}
bitmap_clear (&to_process);
}
/* Update all offsets and possibility for elimination on eliminable
registers. Spill pseudos assigned to registers which are
uneliminable, update LRA_NO_ALLOC_REGS and ELIMINABLE_REG_SET. Add
insns to INSNS_WITH_CHANGED_OFFSETS containing eliminable hard
registers whose offsets should be changed. Return true if any
elimination offset changed. */
static bool
update_reg_eliminate (bitmap insns_with_changed_offsets)
{
bool prev, result;
struct lra_elim_table *ep, *ep1;
HARD_REG_SET temp_hard_reg_set;
/* Clear self elimination offsets. */
for (ep = reg_eliminate; ep < ®_eliminate[NUM_ELIMINABLE_REGS]; ep++)
self_elim_offsets[ep->from] = 0;
for (ep = reg_eliminate; ep < ®_eliminate[NUM_ELIMINABLE_REGS]; ep++)
{
/* If it is a currently used elimination: update the previous
offset. */
if (elimination_map[ep->from] == ep)
ep->previous_offset = ep->offset;
prev = ep->prev_can_eliminate;
setup_can_eliminate (ep, targetm.can_eliminate (ep->from, ep->to));
if (ep->can_eliminate && ! prev)
{
/* It is possible that not eliminable register becomes
eliminable because we took other reasons into account to
set up eliminable regs in the initial set up. Just
ignore new eliminable registers. */
setup_can_eliminate (ep, false);
continue;
}
if (ep->can_eliminate != prev && elimination_map[ep->from] == ep)
{
/* We cannot use this elimination anymore -- find another
one. */
if (lra_dump_file != NULL)
fprintf (lra_dump_file,
" Elimination %d to %d is not possible anymore\n",
ep->from, ep->to);
/* If after processing RTL we decides that SP can be used as
a result of elimination, it can not be changed. */
gcc_assert ((ep->to_rtx != stack_pointer_rtx)
|| (ep->from < FIRST_PSEUDO_REGISTER
&& fixed_regs [ep->from]));
/* Mark that is not eliminable anymore. */
elimination_map[ep->from] = NULL;
for (ep1 = ep + 1; ep1 < ®_eliminate[NUM_ELIMINABLE_REGS]; ep1++)
if (ep1->can_eliminate && ep1->from == ep->from)
break;
if (ep1 < ®_eliminate[NUM_ELIMINABLE_REGS])
{
if (lra_dump_file != NULL)
fprintf (lra_dump_file, " Using elimination %d to %d now\n",
ep1->from, ep1->to);
lra_assert (ep1->previous_offset == 0);
ep1->previous_offset = ep->offset;
}
else
{
/* There is no elimination anymore just use the hard
register `from' itself. Setup self elimination
offset to restore the original offset values. */
if (lra_dump_file != NULL)
fprintf (lra_dump_file, " %d is not eliminable at all\n",
ep->from);
self_elim_offsets[ep->from] = -ep->offset;
if (ep->offset != 0)
bitmap_ior_into (insns_with_changed_offsets,
&lra_reg_info[ep->from].insn_bitmap);
}
}
INITIAL_ELIMINATION_OFFSET (ep->from, ep->to, ep->offset);
}
setup_elimination_map ();
result = false;
CLEAR_HARD_REG_SET (temp_hard_reg_set);
for (ep = reg_eliminate; ep < ®_eliminate[NUM_ELIMINABLE_REGS]; ep++)
if (elimination_map[ep->from] == NULL)
SET_HARD_REG_BIT (temp_hard_reg_set, ep->from);
else if (elimination_map[ep->from] == ep)
{
/* Prevent the hard register into which we eliminate from
the usage for pseudos. */
if (ep->from != ep->to)
SET_HARD_REG_BIT (temp_hard_reg_set, ep->to);
if (ep->previous_offset != ep->offset)
{
bitmap_ior_into (insns_with_changed_offsets,
&lra_reg_info[ep->from].insn_bitmap);
/* Update offset when the eliminate offset have been
changed. */
lra_update_reg_val_offset (lra_reg_info[ep->from].val,
ep->offset - ep->previous_offset);
result = true;
}
}
IOR_HARD_REG_SET (lra_no_alloc_regs, temp_hard_reg_set);
AND_COMPL_HARD_REG_SET (eliminable_regset, temp_hard_reg_set);
spill_pseudos (temp_hard_reg_set);
return result;
}
