/* Mark pseudo REGNO as not living at program point POINT and update
START_DYING.
This finishes the current live range for the pseudo corresponding
to REGNO. */
static void
mark_pseudo_dead (int regno, int point)
{
lra_live_range_t p;
lra_assert (regno >= FIRST_PSEUDO_REGISTER);
lra_assert (sparseset_bit_p (pseudos_live, regno));
sparseset_clear_bit (pseudos_live, regno);
sparseset_set_bit (start_dying, regno);
if (complete_info_p || lra_get_regno_hard_regno (regno) < 0)
{
p = lra_reg_info[regno].live_ranges;
lra_assert (p != NULL);
p->finish = point;
}
}
/* 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);
}
/* Process the death of hard register REGNO. This updates
hard_regs_live and START_DYING. */
static void
make_hard_regno_dead (int regno)
{
lra_assert (regno < FIRST_PSEUDO_REGISTER);
if (! TEST_HARD_REG_BIT (hard_regs_live, regno))
return;
sparseset_set_bit (start_dying, regno);
CLEAR_HARD_REG_BIT (hard_regs_live, regno);
}
/* Merge *non-intersected* ranges R1 and R2 and returns the result.
The function maintains the order of ranges and tries to minimize
size of the result range list. Ranges R1 and R2 may not be used
after the call. */
lra_live_range_t
lra_merge_live_ranges (lra_live_range_t r1, lra_live_range_t r2)
{
lra_live_range_t first, last, temp;
if (r1 == NULL)
return r2;
if (r2 == NULL)
return r1;
for (first = last = NULL; r1 != NULL && r2 != NULL;)
{
if (r1->start < r2->start)
{
temp = r1;
r1 = r2;
r2 = temp;
}
if (r1->start == r2->finish + 1)
{
/* Joint ranges: merge r1 and r2 into r1. */
r1->start = r2->start;
temp = r2;
r2 = r2->next;
pool_free (live_range_pool, temp);
}
else
{
gcc_assert (r2->finish + 1 < r1->start);
/* Add r1 to the result. */
if (first == NULL)
first = last = r1;
else
{
last->next = r1;
last = r1;
}
r1 = r1->next;
}
}
if (r1 != NULL)
{
if (first == NULL)
first = r1;
else
last->next = r1;
}
else
{
lra_assert (r2 != NULL);
if (first == NULL)
first = r2;
else
last->next = r2;
}
return first;
}
/* Return true if pseudo REGNO can be potentially coalesced. */
static bool
coalescable_pseudo_p (int regno)
{
lra_assert (regno >= FIRST_PSEUDO_REGISTER);
return (/* We don't want to coalesce regnos with equivalences, at
least without updating this info. */
ira_reg_equiv[regno].constant == NULL_RTX
&& ira_reg_equiv[regno].memory == NULL_RTX
&& ira_reg_equiv[regno].invariant == NULL_RTX);
}
/* The function processing birth of hard register REGNO. It updates
living hard regs, conflict hard regs for living pseudos, and
START_LIVING. */
static void
make_hard_regno_born (int regno)
{
unsigned int i;
lra_assert (regno < FIRST_PSEUDO_REGISTER);
if (TEST_HARD_REG_BIT (hard_regs_live, regno))
return;
SET_HARD_REG_BIT (hard_regs_live, regno);
sparseset_set_bit (start_living, regno);
EXECUTE_IF_SET_IN_SPARSESET (pseudos_live, i)
SET_HARD_REG_BIT (lra_reg_info[i].conflict_hard_regs, regno);
}
/* Return elimination which will be used for hard reg REG, NULL
otherwise. */
static struct lra_elim_table *
get_elimination (rtx reg)
{
int hard_regno;
struct lra_elim_table *ep;
HOST_WIDE_INT offset;
lra_assert (REG_P (reg));
if ((hard_regno = REGNO (reg)) < 0 || hard_regno >= FIRST_PSEUDO_REGISTER)
return NULL;
if ((ep = elimination_map[hard_regno]) != NULL)
return ep->from_rtx != reg ? NULL : ep;
if ((offset = self_elim_offsets[hard_regno]) == 0)
return NULL;
/* This is an iteration to restore offsets just after HARD_REGNO
stopped to be eliminable. */
self_elim_table.from = self_elim_table.to = hard_regno;
self_elim_table.from_rtx
= self_elim_table.to_rtx
= eliminable_reg_rtx[hard_regno];
lra_assert (self_elim_table.from_rtx != NULL);
self_elim_table.offset = offset;
return &self_elim_table;
}
/* Return true if pseudo REGNO can be potentially coalesced. Use
SPLIT_PSEUDO_BITMAP to find pseudos whose live ranges were
split. */
static bool
coalescable_pseudo_p (int regno, bitmap split_origin_bitmap)
{
lra_assert (regno >= FIRST_PSEUDO_REGISTER);
/* Don't coalesce inheritance pseudos because spilled inheritance
pseudos will be removed in subsequent 'undo inheritance'
pass. */
return (lra_reg_info[regno].restore_regno < 0
/* We undo splits for spilled pseudos whose live ranges were
split. So don't coalesce them, it is not necessary and
the undo transformations would be wrong. */
&& ! bitmap_bit_p (split_origin_bitmap, regno)
/* We don't want to coalesce regnos with equivalences, at
least without updating this info. */
&& ira_reg_equiv[regno].constant == NULL_RTX
&& ira_reg_equiv[regno].memory == NULL_RTX
&& ira_reg_equiv[regno].invariant == NULL_RTX);
}
/* The function processing birth of hard register REGNO. It updates
living hard regs, START_LIVING, and conflict hard regs for living
pseudos. Conflict hard regs for the pic pseudo is not updated if
REGNO is REAL_PIC_OFFSET_TABLE_REGNUM and CHECK_PIC_PSEUDO_P is
true. */
static void
make_hard_regno_born (int regno, bool check_pic_pseudo_p ATTRIBUTE_UNUSED)
{
unsigned int i;
lra_assert (regno < FIRST_PSEUDO_REGISTER);
if (TEST_HARD_REG_BIT (hard_regs_live, regno))
return;
SET_HARD_REG_BIT (hard_regs_live, regno);
sparseset_set_bit (start_living, regno);
EXECUTE_IF_SET_IN_SPARSESET (pseudos_live, i)
#ifdef REAL_PIC_OFFSET_TABLE_REGNUM
if (! check_pic_pseudo_p
|| regno != REAL_PIC_OFFSET_TABLE_REGNUM
|| pic_offset_table_rtx == NULL
|| i != REGNO (pic_offset_table_rtx))
#endif
SET_HARD_REG_BIT (lra_reg_info[i].conflict_hard_regs, regno);
}
/* The major function for aggressive pseudo coalescing of moves only
if the both pseudos were spilled and not special reload pseudos. */
bool
lra_coalesce (void)
{
basic_block bb;
rtx mv, set, insn, next, *sorted_moves;
int i, mv_num, sregno, dregno;
int coalesced_moves;
int max_regno = max_reg_num ();
bitmap_head involved_insns_bitmap;
timevar_push (TV_LRA_COALESCE);
if (lra_dump_file != NULL)
fprintf (lra_dump_file,
"\n********** Pseudos coalescing #%d: **********\n\n",
++lra_coalesce_iter);
first_coalesced_pseudo = XNEWVEC (int, max_regno);
next_coalesced_pseudo = XNEWVEC (int, max_regno);
for (i = 0; i < max_regno; i++)
first_coalesced_pseudo[i] = next_coalesced_pseudo[i] = i;
sorted_moves = XNEWVEC (rtx, get_max_uid ());
mv_num = 0;
/* Collect moves. */
coalesced_moves = 0;
FOR_EACH_BB (bb)
{
FOR_BB_INSNS_SAFE (bb, insn, next)
if (INSN_P (insn)
&& (set = single_set (insn)) != NULL_RTX
&& REG_P (SET_DEST (set)) && REG_P (SET_SRC (set))
&& (sregno = REGNO (SET_SRC (set))) >= FIRST_PSEUDO_REGISTER
&& (dregno = REGNO (SET_DEST (set))) >= FIRST_PSEUDO_REGISTER
&& mem_move_p (sregno, dregno)
&& coalescable_pseudo_p (sregno) && coalescable_pseudo_p (dregno)
&& ! side_effects_p (set)
&& !(lra_intersected_live_ranges_p
(lra_reg_info[sregno].live_ranges,
lra_reg_info[dregno].live_ranges)))
sorted_moves[mv_num++] = insn;
}
qsort (sorted_moves, mv_num, sizeof (rtx), move_freq_compare_func);
/* Coalesced copies, most frequently executed first. */
bitmap_initialize (&coalesced_pseudos_bitmap, ®_obstack);
bitmap_initialize (&involved_insns_bitmap, ®_obstack);
for (i = 0; i < mv_num; i++)
{
mv = sorted_moves[i];
set = single_set (mv);
lra_assert (set != NULL && REG_P (SET_SRC (set))
&& REG_P (SET_DEST (set)));
sregno = REGNO (SET_SRC (set));
dregno = REGNO (SET_DEST (set));
if (first_coalesced_pseudo[sregno] == first_coalesced_pseudo[dregno])
{
coalesced_moves++;
if (lra_dump_file != NULL)
fprintf
(lra_dump_file, " Coalescing move %i:r%d-r%d (freq=%d)\n",
INSN_UID (mv), sregno, dregno,
BLOCK_FOR_INSN (mv)->frequency);
/* We updated involved_insns_bitmap when doing the merge. */
}
else if (!(lra_intersected_live_ranges_p
(lra_reg_info[first_coalesced_pseudo[sregno]].live_ranges,
lra_reg_info[first_coalesced_pseudo[dregno]].live_ranges)))
{
coalesced_moves++;
if (lra_dump_file != NULL)
fprintf
(lra_dump_file,
" Coalescing move %i:r%d(%d)-r%d(%d) (freq=%d)\n",
INSN_UID (mv), sregno, ORIGINAL_REGNO (SET_SRC (set)),
dregno, ORIGINAL_REGNO (SET_DEST (set)),
BLOCK_FOR_INSN (mv)->frequency);
bitmap_ior_into (&involved_insns_bitmap,
&lra_reg_info[sregno].insn_bitmap);
bitmap_ior_into (&involved_insns_bitmap,
&lra_reg_info[dregno].insn_bitmap);
merge_pseudos (sregno, dregno);
}
}
bitmap_initialize (&used_pseudos_bitmap, ®_obstack);
FOR_EACH_BB (bb)
{
update_live_info (df_get_live_in (bb));
update_live_info (df_get_live_out (bb));
FOR_BB_INSNS_SAFE (bb, insn, next)
if (INSN_P (insn)
&& bitmap_bit_p (&involved_insns_bitmap, INSN_UID (insn)))
{
if (! substitute (&insn))
continue;
lra_update_insn_regno_info (insn);
if ((set = single_set (insn)) != NULL_RTX && set_noop_p (set))
{
/* Coalesced move. */
if (lra_dump_file != NULL)
fprintf (lra_dump_file, " Removing move %i (freq=%d)\n",
INSN_UID (insn), BLOCK_FOR_INSN (insn)->frequency);
lra_set_insn_deleted (insn);
}
}
}
bitmap_clear (&used_pseudos_bitmap);
bitmap_clear (&involved_insns_bitmap);
bitmap_clear (&coalesced_pseudos_bitmap);
if (lra_dump_file != NULL && coalesced_moves != 0)
fprintf (lra_dump_file, "Coalesced Moves = %d\n", coalesced_moves);
free (sorted_moves);
free (next_coalesced_pseudo);
free (first_coalesced_pseudo);
timevar_pop (TV_LRA_COALESCE);
return coalesced_moves != 0;
}
void
eliminate_regs_in_insn (rtx_insn *insn, bool replace_p, bool first_p,
HOST_WIDE_INT update_sp_offset)
{
int icode = recog_memoized (insn);
rtx old_set = single_set (insn);
bool validate_p;
int i;
rtx substed_operand[MAX_RECOG_OPERANDS];
rtx orig_operand[MAX_RECOG_OPERANDS];
struct lra_elim_table *ep;
rtx plus_src, plus_cst_src;
lra_insn_recog_data_t id;
struct lra_static_insn_data *static_id;
if (icode < 0 && asm_noperands (PATTERN (insn)) < 0 && ! DEBUG_INSN_P (insn))
{
lra_assert (GET_CODE (PATTERN (insn)) == USE
|| GET_CODE (PATTERN (insn)) == CLOBBER
|| GET_CODE (PATTERN (insn)) == ASM_INPUT);
return;
}
/* Check for setting an eliminable register. */
if (old_set != 0 && REG_P (SET_DEST (old_set))
&& (ep = get_elimination (SET_DEST (old_set))) != NULL)
{
for (ep = reg_eliminate; ep < ®_eliminate[NUM_ELIMINABLE_REGS]; ep++)
if (ep->from_rtx == SET_DEST (old_set) && ep->can_eliminate)
{
bool delete_p = replace_p;
#ifdef HARD_FRAME_POINTER_REGNUM
if (ep->from == FRAME_POINTER_REGNUM
&& ep->to == HARD_FRAME_POINTER_REGNUM)
/* If this is setting the frame pointer register to the
hardware frame pointer register and this is an
elimination that will be done (tested above), this
insn is really adjusting the frame pointer downward
to compensate for the adjustment done before a
nonlocal goto. */
{
rtx src = SET_SRC (old_set);
rtx off = remove_reg_equal_offset_note (insn, ep->to_rtx);
/* We should never process such insn with non-zero
UPDATE_SP_OFFSET. */
lra_assert (update_sp_offset == 0);
if (off != NULL_RTX
|| src == ep->to_rtx
|| (GET_CODE (src) == PLUS
&& XEXP (src, 0) == ep->to_rtx
&& CONST_INT_P (XEXP (src, 1))))
{
HOST_WIDE_INT offset;
if (replace_p)
{
SET_DEST (old_set) = ep->to_rtx;
lra_update_insn_recog_data (insn);
return;
}
offset = (off != NULL_RTX ? INTVAL (off)
: src == ep->to_rtx ? 0 : INTVAL (XEXP (src, 1)));
offset -= (ep->offset - ep->previous_offset);
src = plus_constant (Pmode, ep->to_rtx, offset);
/* First see if this insn remains valid when we
make the change. If not, keep the INSN_CODE
the same and let the constraint pass fit it
up. */
validate_change (insn, &SET_SRC (old_set), src, 1);
validate_change (insn, &SET_DEST (old_set),
ep->from_rtx, 1);
if (! apply_change_group ())
{
SET_SRC (old_set) = src;
SET_DEST (old_set) = ep->from_rtx;
}
lra_update_insn_recog_data (insn);
/* Add offset note for future updates. */
add_reg_note (insn, REG_EQUAL, src);
return;
}
}
#endif
/* This insn isn't serving a useful purpose. We delete it
when REPLACE is set. */
if (delete_p)
lra_delete_dead_insn (insn);
return;
}
}
/* We allow one special case which happens to work on all machines we
currently support: a single set with the source or a REG_EQUAL
note being a PLUS of an eliminable register and a constant. */
plus_src = plus_cst_src = 0;
if (old_set && REG_P (SET_DEST (old_set)))
{
if (GET_CODE (SET_SRC (old_set)) == PLUS)
plus_src = SET_SRC (old_set);
/* First see if the source is of the form (plus (...) CST). */
if (plus_src
&& CONST_INT_P (XEXP (plus_src, 1)))
plus_cst_src = plus_src;
/* Check that the first operand of the PLUS is a hard reg or
the lowpart subreg of one. */
if (plus_cst_src)
{
rtx reg = XEXP (plus_cst_src, 0);
if (GET_CODE (reg) == SUBREG && subreg_lowpart_p (reg))
reg = SUBREG_REG (reg);
if (!REG_P (reg) || REGNO (reg) >= FIRST_PSEUDO_REGISTER)
plus_cst_src = 0;
}
}
if (plus_cst_src)
{
rtx reg = XEXP (plus_cst_src, 0);
HOST_WIDE_INT offset = INTVAL (XEXP (plus_cst_src, 1));
if (GET_CODE (reg) == SUBREG)
reg = SUBREG_REG (reg);
if (REG_P (reg) && (ep = get_elimination (reg)) != NULL)
{
rtx to_rtx = replace_p ? ep->to_rtx : ep->from_rtx;
if (! replace_p)
{
if (update_sp_offset == 0)
offset += (ep->offset - ep->previous_offset);
if (ep->to_rtx == stack_pointer_rtx)
{
if (first_p)
offset -= lra_get_insn_recog_data (insn)->sp_offset;
else
offset += update_sp_offset;
}
offset = trunc_int_for_mode (offset, GET_MODE (plus_cst_src));
}
if (GET_CODE (XEXP (plus_cst_src, 0)) == SUBREG)
to_rtx = gen_lowpart (GET_MODE (XEXP (plus_cst_src, 0)), to_rtx);
/* If we have a nonzero offset, and the source is already a
simple REG, the following transformation would increase
the cost of the insn by replacing a simple REG with (plus
(reg sp) CST). So try only when we already had a PLUS
before. */
if (offset == 0 || plus_src)
{
rtx new_src = plus_constant (GET_MODE (to_rtx), to_rtx, offset);
old_set = single_set (insn);
/* First see if this insn remains valid when we make the
change. If not, try to replace the whole pattern
with a simple set (this may help if the original insn
was a PARALLEL that was only recognized as single_set
due to REG_UNUSED notes). If this isn't valid
either, keep the INSN_CODE the same and let the
constraint pass fix it up. */
if (! validate_change (insn, &SET_SRC (old_set), new_src, 0))
{
rtx new_pat = gen_rtx_SET (SET_DEST (old_set), new_src);
if (! validate_change (insn, &PATTERN (insn), new_pat, 0))
SET_SRC (old_set) = new_src;
}
lra_update_insn_recog_data (insn);
/* This can't have an effect on elimination offsets, so skip
right to the end. */
return;
}
}
}
/* Eliminate all eliminable registers occurring in operands that
can be handled by the constraint pass. */
id = lra_get_insn_recog_data (insn);
static_id = id->insn_static_data;
validate_p = false;
for (i = 0; i < static_id->n_operands; i++)
{
orig_operand[i] = *id->operand_loc[i];
substed_operand[i] = *id->operand_loc[i];
/* For an asm statement, every operand is eliminable. */
if (icode < 0 || insn_data[icode].operand[i].eliminable)
{
/* Check for setting a hard register that we know about. */
if (static_id->operand[i].type != OP_IN
&& REG_P (orig_operand[i]))
{
/* If we are assigning to a hard register that can be
eliminated, it must be as part of a PARALLEL, since
the code above handles single SETs. This reg can not
be longer eliminated -- it is forced by
mark_not_eliminable. */
for (ep = reg_eliminate;
ep < ®_eliminate[NUM_ELIMINABLE_REGS];
ep++)
lra_assert (ep->from_rtx != orig_operand[i]
|| ! ep->can_eliminate);
}
/* Companion to the above plus substitution, we can allow
invariants as the source of a plain move. */
substed_operand[i]
= lra_eliminate_regs_1 (insn, *id->operand_loc[i], VOIDmode,
replace_p, ! replace_p && ! first_p,
update_sp_offset, first_p);
if (substed_operand[i] != orig_operand[i])
validate_p = true;
}
}
if (! validate_p)
return;
/* Substitute the operands; the new values are in the substed_operand
array. */
for (i = 0; i < static_id->n_operands; i++)
*id->operand_loc[i] = substed_operand[i];
for (i = 0; i < static_id->n_dups; i++)
*id->dup_loc[i] = substed_operand[(int) static_id->dup_num[i]];
/* If we had a move insn but now we don't, re-recognize it.
This will cause spurious re-recognition if the old move had a
PARALLEL since the new one still will, but we can't call
single_set without having put new body into the insn and the
re-recognition won't hurt in this rare case. */
id = lra_update_insn_recog_data (insn);
static_id = id->insn_static_data;
}
/* Scan X and replace any eliminable registers (such as fp) with a
replacement (such as sp) if SUBST_P, plus an offset. The offset is
a change in the offset between the eliminable register and its
substitution if UPDATE_P, or the full offset if FULL_P, or
otherwise zero. If FULL_P, we also use the SP offsets for
elimination to SP. If UPDATE_P, use UPDATE_SP_OFFSET for updating
offsets of register elimnable to SP. If UPDATE_SP_OFFSET is
non-zero, don't use difference of the offset and the previous
offset.
MEM_MODE is the mode of an enclosing MEM. We need this to know how
much to adjust a register for, e.g., PRE_DEC. Also, if we are
inside a MEM, we are allowed to replace a sum of a hard register
and the constant zero with the hard register, which we cannot do
outside a MEM. In addition, we need to record the fact that a
hard register is referenced outside a MEM.
If we make full substitution to SP for non-null INSN, add the insn
sp offset. */
rtx
lra_eliminate_regs_1 (rtx_insn *insn, rtx x, machine_mode mem_mode,
bool subst_p, bool update_p,
HOST_WIDE_INT update_sp_offset, bool full_p)
{
enum rtx_code code = GET_CODE (x);
struct lra_elim_table *ep;
rtx new_rtx;
int i, j;
const char *fmt;
int copied = 0;
lra_assert (!update_p || !full_p);
lra_assert (update_sp_offset == 0 || (!subst_p && update_p && !full_p));
if (! current_function_decl)
return x;
switch (code)
{
CASE_CONST_ANY:
case CONST:
case SYMBOL_REF:
case CODE_LABEL:
case PC:
case CC0:
case ASM_INPUT:
case ADDR_VEC:
case ADDR_DIFF_VEC:
case RETURN:
return x;
case REG:
/* First handle the case where we encounter a bare hard register
that is eliminable. Replace it with a PLUS. */
if ((ep = get_elimination (x)) != NULL)
{
rtx to = subst_p ? ep->to_rtx : ep->from_rtx;
if (update_sp_offset != 0)
{
if (ep->to_rtx == stack_pointer_rtx)
return plus_constant (Pmode, to, update_sp_offset);
return to;
}
else if (update_p)
return plus_constant (Pmode, to, ep->offset - ep->previous_offset);
else if (full_p)
return plus_constant (Pmode, to,
ep->offset
- (insn != NULL_RTX
&& ep->to_rtx == stack_pointer_rtx
? lra_get_insn_recog_data (insn)->sp_offset
: 0));
else
return to;
}
return x;
case PLUS:
/* If this is the sum of an eliminable register and a constant, rework
the sum. */
if (REG_P (XEXP (x, 0)) && CONSTANT_P (XEXP (x, 1)))
{
if ((ep = get_elimination (XEXP (x, 0))) != NULL)
{
HOST_WIDE_INT offset;
rtx to = subst_p ? ep->to_rtx : ep->from_rtx;
if (! update_p && ! full_p)
return gen_rtx_PLUS (Pmode, to, XEXP (x, 1));
if (update_sp_offset != 0)
offset = ep->to_rtx == stack_pointer_rtx ? update_sp_offset : 0;
else
offset = (update_p
? ep->offset - ep->previous_offset : ep->offset);
if (full_p && insn != NULL_RTX && ep->to_rtx == stack_pointer_rtx)
offset -= lra_get_insn_recog_data (insn)->sp_offset;
if (CONST_INT_P (XEXP (x, 1)) && INTVAL (XEXP (x, 1)) == -offset)
return to;
else
return gen_rtx_PLUS (Pmode, to,
plus_constant (Pmode,
XEXP (x, 1), offset));
}
/* If the hard register is not eliminable, we are done since
the other operand is a constant. */
return x;
}
/* If this is part of an address, we want to bring any constant
to the outermost PLUS. We will do this by doing hard
register replacement in our operands and seeing if a constant
shows up in one of them.
Note that there is no risk of modifying the structure of the
insn, since we only get called for its operands, thus we are
either modifying the address inside a MEM, or something like
an address operand of a load-address insn. */
{
rtx new0 = lra_eliminate_regs_1 (insn, XEXP (x, 0), mem_mode,
subst_p, update_p,
update_sp_offset, full_p);
rtx new1 = lra_eliminate_regs_1 (insn, XEXP (x, 1), mem_mode,
subst_p, update_p,
update_sp_offset, full_p);
new0 = move_plus_up (new0);
new1 = move_plus_up (new1);
if (new0 != XEXP (x, 0) || new1 != XEXP (x, 1))
return form_sum (new0, new1);
}
return x;
case MULT:
/* If this is the product of an eliminable hard register and a
constant, apply the distribute law and move the constant out
so that we have (plus (mult ..) ..). This is needed in order
to keep load-address insns valid. This case is pathological.
We ignore the possibility of overflow here. */
if (REG_P (XEXP (x, 0)) && CONST_INT_P (XEXP (x, 1))
&& (ep = get_elimination (XEXP (x, 0))) != NULL)
{
rtx to = subst_p ? ep->to_rtx : ep->from_rtx;
if (update_sp_offset != 0)
{
if (ep->to_rtx == stack_pointer_rtx)
return plus_constant (Pmode,
gen_rtx_MULT (Pmode, to, XEXP (x, 1)),
update_sp_offset * INTVAL (XEXP (x, 1)));
return gen_rtx_MULT (Pmode, to, XEXP (x, 1));
}
else if (update_p)
return plus_constant (Pmode,
gen_rtx_MULT (Pmode, to, XEXP (x, 1)),
(ep->offset - ep->previous_offset)
* INTVAL (XEXP (x, 1)));
else if (full_p)
{
HOST_WIDE_INT offset = ep->offset;
if (insn != NULL_RTX && ep->to_rtx == stack_pointer_rtx)
offset -= lra_get_insn_recog_data (insn)->sp_offset;
return
plus_constant (Pmode,
gen_rtx_MULT (Pmode, to, XEXP (x, 1)),
offset * INTVAL (XEXP (x, 1)));
}
else
return gen_rtx_MULT (Pmode, to, XEXP (x, 1));
}
/* fall through */
case CALL:
case COMPARE:
/* See comments before PLUS about handling MINUS. */
case MINUS:
case DIV: case UDIV:
case MOD: case UMOD:
case AND: case IOR: case XOR:
case ROTATERT: case ROTATE:
case ASHIFTRT: case LSHIFTRT: case ASHIFT:
case NE: case EQ:
case GE: case GT: case GEU: case GTU:
case LE: case LT: case LEU: case LTU:
{
rtx new0 = lra_eliminate_regs_1 (insn, XEXP (x, 0), mem_mode,
subst_p, update_p,
update_sp_offset, full_p);
rtx new1 = XEXP (x, 1)
? lra_eliminate_regs_1 (insn, XEXP (x, 1), mem_mode,
subst_p, update_p,
update_sp_offset, full_p) : 0;
if (new0 != XEXP (x, 0) || new1 != XEXP (x, 1))
return gen_rtx_fmt_ee (code, GET_MODE (x), new0, new1);
}
return x;
case EXPR_LIST:
/* If we have something in XEXP (x, 0), the usual case,
eliminate it. */
if (XEXP (x, 0))
{
new_rtx = lra_eliminate_regs_1 (insn, XEXP (x, 0), mem_mode,
subst_p, update_p,
update_sp_offset, full_p);
if (new_rtx != XEXP (x, 0))
{
/* If this is a REG_DEAD note, it is not valid anymore.
Using the eliminated version could result in creating a
REG_DEAD note for the stack or frame pointer. */
if (REG_NOTE_KIND (x) == REG_DEAD)
return (XEXP (x, 1)
? lra_eliminate_regs_1 (insn, XEXP (x, 1), mem_mode,
subst_p, update_p,
update_sp_offset, full_p)
: NULL_RTX);
x = alloc_reg_note (REG_NOTE_KIND (x), new_rtx, XEXP (x, 1));
}
}
/* fall through */
case INSN_LIST:
case INT_LIST:
/* Now do eliminations in the rest of the chain. If this was
an EXPR_LIST, this might result in allocating more memory than is
strictly needed, but it simplifies the code. */
if (XEXP (x, 1))
{
new_rtx = lra_eliminate_regs_1 (insn, XEXP (x, 1), mem_mode,
subst_p, update_p,
update_sp_offset, full_p);
if (new_rtx != XEXP (x, 1))
return
gen_rtx_fmt_ee (GET_CODE (x), GET_MODE (x),
XEXP (x, 0), new_rtx);
}
return x;
case PRE_INC:
case POST_INC:
case PRE_DEC:
case POST_DEC:
/* We do not support elimination of a register that is modified.
elimination_effects has already make sure that this does not
happen. */
return x;
case PRE_MODIFY:
case POST_MODIFY:
/* We do not support elimination of a hard register that is
modified. LRA has already make sure that this does not
happen. The only remaining case we need to consider here is
that the increment value may be an eliminable register. */
if (GET_CODE (XEXP (x, 1)) == PLUS
&& XEXP (XEXP (x, 1), 0) == XEXP (x, 0))
{
rtx new_rtx = lra_eliminate_regs_1 (insn, XEXP (XEXP (x, 1), 1),
mem_mode, subst_p, update_p,
update_sp_offset, full_p);
if (new_rtx != XEXP (XEXP (x, 1), 1))
return gen_rtx_fmt_ee (code, GET_MODE (x), XEXP (x, 0),
gen_rtx_PLUS (GET_MODE (x),
XEXP (x, 0), new_rtx));
}
return x;
case STRICT_LOW_PART:
case NEG: case NOT:
case SIGN_EXTEND: case ZERO_EXTEND:
case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
case FLOAT: case FIX:
case UNSIGNED_FIX: case UNSIGNED_FLOAT:
case ABS:
case SQRT:
case FFS:
case CLZ:
case CTZ:
case POPCOUNT:
case PARITY:
case BSWAP:
new_rtx = lra_eliminate_regs_1 (insn, XEXP (x, 0), mem_mode,
subst_p, update_p,
update_sp_offset, full_p);
if (new_rtx != XEXP (x, 0))
return gen_rtx_fmt_e (code, GET_MODE (x), new_rtx);
return x;
case SUBREG:
new_rtx = lra_eliminate_regs_1 (insn, SUBREG_REG (x), mem_mode,
subst_p, update_p,
update_sp_offset, full_p);
if (new_rtx != SUBREG_REG (x))
{
int x_size = GET_MODE_SIZE (GET_MODE (x));
int new_size = GET_MODE_SIZE (GET_MODE (new_rtx));
if (MEM_P (new_rtx) && x_size <= new_size)
{
SUBREG_REG (x) = new_rtx;
alter_subreg (&x, false);
return x;
}
else if (! subst_p)
{
/* LRA can transform subregs itself. So don't call
simplify_gen_subreg until LRA transformations are
finished. Function simplify_gen_subreg can do
non-trivial transformations (like truncation) which
might make LRA work to fail. */
SUBREG_REG (x) = new_rtx;
return x;
}
else
return simplify_gen_subreg (GET_MODE (x), new_rtx,
GET_MODE (new_rtx), SUBREG_BYTE (x));
}
return x;
case MEM:
/* Our only special processing is to pass the mode of the MEM to our
recursive call and copy the flags. While we are here, handle this
case more efficiently. */
return
replace_equiv_address_nv
(x,
lra_eliminate_regs_1 (insn, XEXP (x, 0), GET_MODE (x),
subst_p, update_p, update_sp_offset, full_p));
case USE:
/* Handle insn_list USE that a call to a pure function may generate. */
new_rtx = lra_eliminate_regs_1 (insn, XEXP (x, 0), VOIDmode,
subst_p, update_p, update_sp_offset, full_p);
if (new_rtx != XEXP (x, 0))
return gen_rtx_USE (GET_MODE (x), new_rtx);
return x;
case CLOBBER:
case SET:
gcc_unreachable ();
default:
break;
}
/* Process each of our operands recursively. If any have changed, make a
copy of the rtx. */
fmt = GET_RTX_FORMAT (code);
for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
{
if (*fmt == 'e')
{
new_rtx = lra_eliminate_regs_1 (insn, XEXP (x, i), mem_mode,
subst_p, update_p,
update_sp_offset, full_p);
if (new_rtx != XEXP (x, i) && ! copied)
{
x = shallow_copy_rtx (x);
copied = 1;
}
XEXP (x, i) = new_rtx;
}
else if (*fmt == 'E')
{
int copied_vec = 0;
for (j = 0; j < XVECLEN (x, i); j++)
{
new_rtx = lra_eliminate_regs_1 (insn, XVECEXP (x, i, j), mem_mode,
subst_p, update_p,
update_sp_offset, full_p);
if (new_rtx != XVECEXP (x, i, j) && ! copied_vec)
{
rtvec new_v = gen_rtvec_v (XVECLEN (x, i),
XVEC (x, i)->elem);
if (! copied)
{
x = shallow_copy_rtx (x);
copied = 1;
}
XVEC (x, i) = new_v;
copied_vec = 1;
}
XVECEXP (x, i, j) = new_rtx;
}
}
}
return x;
}
/* 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;
}
