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/* Code for RTL transformations to satisfy insn constraints.
Copyright (C) 2010-2015 Free Software Foundation, Inc.
Contributed by Vladimir Makarov <vmakarov@redhat.com>.
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
/* This file contains code for 3 passes: constraint pass,
inheritance/split pass, and pass for undoing failed inheritance and
split.
The major goal of constraint pass is to transform RTL to satisfy
insn and address constraints by:
o choosing insn alternatives;
o generating *reload insns* (or reloads in brief) and *reload
pseudos* which will get necessary hard registers later;
o substituting pseudos with equivalent values and removing the
instructions that initialized those pseudos.
The constraint pass has biggest and most complicated code in LRA.
There are a lot of important details like:
o reuse of input reload pseudos to simplify reload pseudo
allocations;
o some heuristics to choose insn alternative to improve the
inheritance;
o early clobbers etc.
The pass is mimicking former reload pass in alternative choosing
because the reload pass is oriented to current machine description
model. It might be changed if the machine description model is
changed.
There is special code for preventing all LRA and this pass cycling
in case of bugs.
On the first iteration of the pass we process every instruction and
choose an alternative for each one. On subsequent iterations we try
to avoid reprocessing instructions if we can be sure that the old
choice is still valid.
The inheritance/spilt pass is to transform code to achieve
ineheritance and live range splitting. It is done on backward
traversal of EBBs.
The inheritance optimization goal is to reuse values in hard
registers. There is analogous optimization in old reload pass. The
inheritance is achieved by following transformation:
reload_p1 <- p reload_p1 <- p
... new_p <- reload_p1
... => ...
reload_p2 <- p reload_p2 <- new_p
where p is spilled and not changed between the insns. Reload_p1 is
also called *original pseudo* and new_p is called *inheritance
pseudo*.
The subsequent assignment pass will try to assign the same (or
another if it is not possible) hard register to new_p as to
reload_p1 or reload_p2.
If the assignment pass fails to assign a hard register to new_p,
this file will undo the inheritance and restore the original code.
This is because implementing the above sequence with a spilled
new_p would make the code much worse. The inheritance is done in
EBB scope. The above is just a simplified example to get an idea
of the inheritance as the inheritance is also done for non-reload
insns.
Splitting (transformation) is also done in EBB scope on the same
pass as the inheritance:
r <- ... or ... <- r r <- ... or ... <- r
... s <- r (new insn -- save)
... =>
... r <- s (new insn -- restore)
... <- r ... <- r
The *split pseudo* s is assigned to the hard register of the
original pseudo or hard register r.
Splitting is done:
o In EBBs with high register pressure for global pseudos (living
in at least 2 BBs) and assigned to hard registers when there
are more one reloads needing the hard registers;
o for pseudos needing save/restore code around calls.
If the split pseudo still has the same hard register as the
original pseudo after the subsequent assignment pass or the
original pseudo was split, the opposite transformation is done on
the same pass for undoing inheritance. */
#undef REG_OK_STRICT
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "hard-reg-set.h"
#include "rtl.h"
#include "tm_p.h"
#include "regs.h"
#include "insn-config.h"
#include "insn-codes.h"
#include "recog.h"
#include "output.h"
#include "addresses.h"
#include "target.h"
#include "hashtab.h"
#include "hash-set.h"
#include "vec.h"
#include "machmode.h"
#include "input.h"
#include "function.h"
#include "symtab.h"
#include "flags.h"
#include "statistics.h"
#include "double-int.h"
#include "real.h"
#include "fixed-value.h"
#include "alias.h"
#include "wide-int.h"
#include "inchash.h"
#include "tree.h"
#include "expmed.h"
#include "dojump.h"
#include "explow.h"
#include "calls.h"
#include "emit-rtl.h"
#include "varasm.h"
#include "stmt.h"
#include "expr.h"
#include "predict.h"
#include "dominance.h"
#include "cfg.h"
#include "cfgrtl.h"
#include "basic-block.h"
#include "except.h"
#include "optabs.h"
#include "df.h"
#include "ira.h"
#include "rtl-error.h"
#include "params.h"
#include "lra-int.h"
/* Value of LRA_CURR_RELOAD_NUM at the beginning of BB of the current
insn. Remember that LRA_CURR_RELOAD_NUM is the number of emitted
reload insns. */
static int bb_reload_num;
/* The current insn being processed and corresponding its single set
(NULL otherwise), its data (basic block, the insn data, the insn
static data, and the mode of each operand). */
static rtx_insn *curr_insn;
static rtx curr_insn_set;
static basic_block curr_bb;
static lra_insn_recog_data_t curr_id;
static struct lra_static_insn_data *curr_static_id;
static machine_mode curr_operand_mode[MAX_RECOG_OPERANDS];
/* Mode of the register substituted by its equivalence with VOIDmode
(e.g. constant) and whose subreg is given operand of the current
insn. VOIDmode in all other cases. */
static machine_mode original_subreg_reg_mode[MAX_RECOG_OPERANDS];
/* Start numbers for new registers and insns at the current constraints
pass start. */
static int new_regno_start;
static int new_insn_uid_start;
/* If LOC is nonnull, strip any outer subreg from it. */
static inline rtx *
strip_subreg (rtx *loc)
{
return loc && GET_CODE (*loc) == SUBREG ? &SUBREG_REG (*loc) : loc;
}
/* Return hard regno of REGNO or if it is was not assigned to a hard
register, use a hard register from its allocno class. */
static int
get_try_hard_regno (int regno)
{
int hard_regno;
enum reg_class rclass;
if ((hard_regno = regno) >= FIRST_PSEUDO_REGISTER)
hard_regno = lra_get_regno_hard_regno (regno);
if (hard_regno >= 0)
return hard_regno;
rclass = lra_get_allocno_class (regno);
if (rclass == NO_REGS)
return -1;
return ira_class_hard_regs[rclass][0];
}
/* Return final hard regno (plus offset) which will be after
elimination. We do this for matching constraints because the final
hard regno could have a different class. */
static int
get_final_hard_regno (int hard_regno, int offset)
{
if (hard_regno < 0)
return hard_regno;
hard_regno = lra_get_elimination_hard_regno (hard_regno);
return hard_regno + offset;
}
/* Return hard regno of X after removing subreg and making
elimination. If X is not a register or subreg of register, return
-1. For pseudo use its assignment. */
static int
get_hard_regno (rtx x)
{
rtx reg;
int offset, hard_regno;
reg = x;
if (GET_CODE (x) == SUBREG)
reg = SUBREG_REG (x);
if (! REG_P (reg))
return -1;
if ((hard_regno = REGNO (reg)) >= FIRST_PSEUDO_REGISTER)
hard_regno = lra_get_regno_hard_regno (hard_regno);
if (hard_regno < 0)
return -1;
offset = 0;
if (GET_CODE (x) == SUBREG)
offset += subreg_regno_offset (hard_regno, GET_MODE (reg),
SUBREG_BYTE (x), GET_MODE (x));
return get_final_hard_regno (hard_regno, offset);
}
/* If REGNO is a hard register or has been allocated a hard register,
return the class of that register. If REGNO is a reload pseudo
created by the current constraints pass, return its allocno class.
Return NO_REGS otherwise. */
static enum reg_class
get_reg_class (int regno)
{
int hard_regno;
if ((hard_regno = regno) >= FIRST_PSEUDO_REGISTER)
hard_regno = lra_get_regno_hard_regno (regno);
if (hard_regno >= 0)
{
hard_regno = get_final_hard_regno (hard_regno, 0);
return REGNO_REG_CLASS (hard_regno);
}
if (regno >= new_regno_start)
return lra_get_allocno_class (regno);
return NO_REGS;
}
/* Return true if REG satisfies (or will satisfy) reg class constraint
CL. Use elimination first if REG is a hard register. If REG is a
reload pseudo created by this constraints pass, assume that it will
be allocated a hard register from its allocno class, but allow that
class to be narrowed to CL if it is currently a superset of CL.
If NEW_CLASS is nonnull, set *NEW_CLASS to the new allocno class of
REGNO (reg), or NO_REGS if no change in its class was needed. */
static bool
in_class_p (rtx reg, enum reg_class cl, enum reg_class *new_class)
{
enum reg_class rclass, common_class;
machine_mode reg_mode;
int class_size, hard_regno, nregs, i, j;
int regno = REGNO (reg);
if (new_class != NULL)
*new_class = NO_REGS;
if (regno < FIRST_PSEUDO_REGISTER)
{
rtx final_reg = reg;
rtx *final_loc = &final_reg;
lra_eliminate_reg_if_possible (final_loc);
return TEST_HARD_REG_BIT (reg_class_contents[cl], REGNO (*final_loc));
}
reg_mode = GET_MODE (reg);
rclass = get_reg_class (regno);
if (regno < new_regno_start
/* Do not allow the constraints for reload instructions to
influence the classes of new pseudos. These reloads are
typically moves that have many alternatives, and restricting
reload pseudos for one alternative may lead to situations
where other reload pseudos are no longer allocatable. */
|| (INSN_UID (curr_insn) >= new_insn_uid_start
&& curr_insn_set != NULL
&& ((OBJECT_P (SET_SRC (curr_insn_set))
&& ! CONSTANT_P (SET_SRC (curr_insn_set)))
|| (GET_CODE (SET_SRC (curr_insn_set)) == SUBREG
&& OBJECT_P (SUBREG_REG (SET_SRC (curr_insn_set)))
&& ! CONSTANT_P (SUBREG_REG (SET_SRC (curr_insn_set)))))))
/* When we don't know what class will be used finally for reload
pseudos, we use ALL_REGS. */
return ((regno >= new_regno_start && rclass == ALL_REGS)
|| (rclass != NO_REGS && ira_class_subset_p[rclass][cl]
&& ! hard_reg_set_subset_p (reg_class_contents[cl],
lra_no_alloc_regs)));
else
{
common_class = ira_reg_class_subset[rclass][cl];
if (new_class != NULL)
*new_class = common_class;
if (hard_reg_set_subset_p (reg_class_contents[common_class],
lra_no_alloc_regs))
return false;
/* Check that there are enough allocatable regs. */
class_size = ira_class_hard_regs_num[common_class];
for (i = 0; i < class_size; i++)
{
hard_regno = ira_class_hard_regs[common_class][i];
nregs = hard_regno_nregs[hard_regno][reg_mode];
if (nregs == 1)
return true;
for (j = 0; j < nregs; j++)
if (TEST_HARD_REG_BIT (lra_no_alloc_regs, hard_regno + j)
|| ! TEST_HARD_REG_BIT (reg_class_contents[common_class],
hard_regno + j))
break;
if (j >= nregs)
return true;
}
return false;
}
}
/* Return true if REGNO satisfies a memory constraint. */
static bool
in_mem_p (int regno)
{
return get_reg_class (regno) == NO_REGS;
}
/* Return 1 if ADDR is a valid memory address for mode MODE in address
space AS, and check that each pseudo has the proper kind of hard
reg. */
static int
valid_address_p (machine_mode mode ATTRIBUTE_UNUSED,
rtx addr, addr_space_t as)
{
#ifdef GO_IF_LEGITIMATE_ADDRESS
lra_assert (ADDR_SPACE_GENERIC_P (as));
GO_IF_LEGITIMATE_ADDRESS (mode, addr, win);
return 0;
win:
return 1;
#else
return targetm.addr_space.legitimate_address_p (mode, addr, 0, as);
#endif
}
namespace {
/* Temporarily eliminates registers in an address (for the lifetime of
the object). */
class address_eliminator {
public:
address_eliminator (struct address_info *ad);
~address_eliminator ();
private:
struct address_info *m_ad;
rtx *m_base_loc;
rtx m_base_reg;
rtx *m_index_loc;
rtx m_index_reg;
};
}
address_eliminator::address_eliminator (struct address_info *ad)
: m_ad (ad),
m_base_loc (strip_subreg (ad->base_term)),
m_base_reg (NULL_RTX),
m_index_loc (strip_subreg (ad->index_term)),
m_index_reg (NULL_RTX)
{
if (m_base_loc != NULL)
{
m_base_reg = *m_base_loc;
lra_eliminate_reg_if_possible (m_base_loc);
if (m_ad->base_term2 != NULL)
*m_ad->base_term2 = *m_ad->base_term;
}
if (m_index_loc != NULL)
{
m_index_reg = *m_index_loc;
lra_eliminate_reg_if_possible (m_index_loc);
}
}
address_eliminator::~address_eliminator ()
{
if (m_base_loc && *m_base_loc != m_base_reg)
{
*m_base_loc = m_base_reg;
if (m_ad->base_term2 != NULL)
*m_ad->base_term2 = *m_ad->base_term;
}
if (m_index_loc && *m_index_loc != m_index_reg)
*m_index_loc = m_index_reg;
}
/* Return true if the eliminated form of AD is a legitimate target address. */
static bool
valid_address_p (struct address_info *ad)
{
address_eliminator eliminator (ad);
return valid_address_p (ad->mode, *ad->outer, ad->as);
}
/* Return true if the eliminated form of memory reference OP satisfies
extra memory constraint CONSTRAINT. */
static bool
satisfies_memory_constraint_p (rtx op, enum constraint_num constraint)
{
struct address_info ad;
decompose_mem_address (&ad, op);
address_eliminator eliminator (&ad);
return constraint_satisfied_p (op, constraint);
}
/* Return true if the eliminated form of address AD satisfies extra
address constraint CONSTRAINT. */
static bool
satisfies_address_constraint_p (struct address_info *ad,
enum constraint_num constraint)
{
address_eliminator eliminator (ad);
return constraint_satisfied_p (*ad->outer, constraint);
}
/* Return true if the eliminated form of address OP satisfies extra
address constraint CONSTRAINT. */
static bool
satisfies_address_constraint_p (rtx op, enum constraint_num constraint)
{
struct address_info ad;
decompose_lea_address (&ad, &op);
return satisfies_address_constraint_p (&ad, constraint);
}
/* Initiate equivalences for LRA. As we keep original equivalences
before any elimination, we need to make copies otherwise any change
in insns might change the equivalences. */
void
lra_init_equiv (void)
{
ira_expand_reg_equiv ();
for (int i = FIRST_PSEUDO_REGISTER; i < max_reg_num (); i++)
{
rtx res;
if ((res = ira_reg_equiv[i].memory) != NULL_RTX)
ira_reg_equiv[i].memory = copy_rtx (res);
if ((res = ira_reg_equiv[i].invariant) != NULL_RTX)
ira_reg_equiv[i].invariant = copy_rtx (res);
}
}
static rtx loc_equivalence_callback (rtx, const_rtx, void *);
/* Update equivalence for REGNO. We need to this as the equivalence
might contain other pseudos which are changed by their
equivalences. */
static void
update_equiv (int regno)
{
rtx x;
if ((x = ira_reg_equiv[regno].memory) != NULL_RTX)
ira_reg_equiv[regno].memory
= simplify_replace_fn_rtx (x, NULL_RTX, loc_equivalence_callback,
NULL_RTX);
if ((x = ira_reg_equiv[regno].invariant) != NULL_RTX)
ira_reg_equiv[regno].invariant
= simplify_replace_fn_rtx (x, NULL_RTX, loc_equivalence_callback,
NULL_RTX);
}
/* If we have decided to substitute X with another value, return that
value, otherwise return X. */
static rtx
get_equiv (rtx x)
{
int regno;
rtx res;
if (! REG_P (x) || (regno = REGNO (x)) < FIRST_PSEUDO_REGISTER
|| ! ira_reg_equiv[regno].defined_p
|| ! ira_reg_equiv[regno].profitable_p
|| lra_get_regno_hard_regno (regno) >= 0)
return x;
if ((res = ira_reg_equiv[regno].memory) != NULL_RTX)
{
if (targetm.cannot_substitute_mem_equiv_p (res))
return x;
return res;
}
if ((res = ira_reg_equiv[regno].constant) != NULL_RTX)
return res;
if ((res = ira_reg_equiv[regno].invariant) != NULL_RTX)
return res;
gcc_unreachable ();
}
/* If we have decided to substitute X with the equivalent value,
return that value after elimination for INSN, otherwise return
X. */
static rtx
get_equiv_with_elimination (rtx x, rtx_insn *insn)
{
rtx res = get_equiv (x);
if (x == res || CONSTANT_P (res))
return res;
return lra_eliminate_regs_1 (insn, res, GET_MODE (res),
false, false, 0, true);
}
/* Set up curr_operand_mode. */
static void
init_curr_operand_mode (void)
{
int nop = curr_static_id->n_operands;
for (int i = 0; i < nop; i++)
{
machine_mode mode = GET_MODE (*curr_id->operand_loc[i]);
if (mode == VOIDmode)
{
/* The .md mode for address operands is the mode of the
addressed value rather than the mode of the address itself. */
if (curr_id->icode >= 0 && curr_static_id->operand[i].is_address)
mode = Pmode;
else
mode = curr_static_id->operand[i].mode;
}
curr_operand_mode[i] = mode;
}
}
/* The page contains code to reuse input reloads. */
/* Structure describes input reload of the current insns. */
struct input_reload
{
/* Reloaded value. */
rtx input;
/* Reload pseudo used. */
rtx reg;
};
/* The number of elements in the following array. */
static int curr_insn_input_reloads_num;
/* Array containing info about input reloads. It is used to find the
same input reload and reuse the reload pseudo in this case. */
static struct input_reload curr_insn_input_reloads[LRA_MAX_INSN_RELOADS];
/* Initiate data concerning reuse of input reloads for the current
insn. */
static void
init_curr_insn_input_reloads (void)
{
curr_insn_input_reloads_num = 0;
}
/* Create a new pseudo using MODE, RCLASS, ORIGINAL or reuse already
created input reload pseudo (only if TYPE is not OP_OUT). Don't
reuse pseudo if IN_SUBREG_P is true and the reused pseudo should be
wrapped up in SUBREG. The result pseudo is returned through
RESULT_REG. Return TRUE if we created a new pseudo, FALSE if we
reused the already created input reload pseudo. Use TITLE to
describe new registers for debug purposes. */
static bool
get_reload_reg (enum op_type type, machine_mode mode, rtx original,
enum reg_class rclass, bool in_subreg_p,
const char *title, rtx *result_reg)
{
int i, regno;
enum reg_class new_class;
if (type == OP_OUT)
{
*result_reg
= lra_create_new_reg_with_unique_value (mode, original, rclass, title);
return true;
}
/* Prevent reuse value of expression with side effects,
e.g. volatile memory. */
if (! side_effects_p (original))
for (i = 0; i < curr_insn_input_reloads_num; i++)
if (rtx_equal_p (curr_insn_input_reloads[i].input, original)
&& in_class_p (curr_insn_input_reloads[i].reg, rclass, &new_class))
{
rtx reg = curr_insn_input_reloads[i].reg;
regno = REGNO (reg);
/* If input is equal to original and both are VOIDmode,
GET_MODE (reg) might be still different from mode.
Ensure we don't return *result_reg with wrong mode. */
if (GET_MODE (reg) != mode)
{
if (in_subreg_p)
continue;
if (GET_MODE_SIZE (GET_MODE (reg)) < GET_MODE_SIZE (mode))
continue;
reg = lowpart_subreg (mode, reg, GET_MODE (reg));
if (reg == NULL_RTX || GET_CODE (reg) != SUBREG)
continue;
}
*result_reg = reg;
if (lra_dump_file != NULL)
{
fprintf (lra_dump_file, " Reuse r%d for reload ", regno);
dump_value_slim (lra_dump_file, original, 1);
}
if (new_class != lra_get_allocno_class (regno))
lra_change_class (regno, new_class, ", change to", false);
if (lra_dump_file != NULL)
fprintf (lra_dump_file, "\n");
return false;
}
*result_reg = lra_create_new_reg (mode, original, rclass, title);
lra_assert (curr_insn_input_reloads_num < LRA_MAX_INSN_RELOADS);
curr_insn_input_reloads[curr_insn_input_reloads_num].input = original;
curr_insn_input_reloads[curr_insn_input_reloads_num++].reg = *result_reg;
return true;
}
/* The page contains code to extract memory address parts. */
/* Wrapper around REGNO_OK_FOR_INDEX_P, to allow pseudos. */
static inline bool
ok_for_index_p_nonstrict (rtx reg)
{
unsigned regno = REGNO (reg);
return regno >= FIRST_PSEUDO_REGISTER || REGNO_OK_FOR_INDEX_P (regno);
}
/* A version of regno_ok_for_base_p for use here, when all pseudos
should count as OK. Arguments as for regno_ok_for_base_p. */
static inline bool
ok_for_base_p_nonstrict (rtx reg, machine_mode mode, addr_space_t as,
enum rtx_code outer_code, enum rtx_code index_code)
{
unsigned regno = REGNO (reg);
if (regno >= FIRST_PSEUDO_REGISTER)
return true;
return ok_for_base_p_1 (regno, mode, as, outer_code, index_code);
}
/* The page contains major code to choose the current insn alternative
and generate reloads for it. */
/* Return the offset from REGNO of the least significant register
in (reg:MODE REGNO).
This function is used to tell whether two registers satisfy
a matching constraint. (reg:MODE1 REGNO1) matches (reg:MODE2 REGNO2) if:
REGNO1 + lra_constraint_offset (REGNO1, MODE1)
== REGNO2 + lra_constraint_offset (REGNO2, MODE2) */
int
lra_constraint_offset (int regno, machine_mode mode)
{
lra_assert (regno < FIRST_PSEUDO_REGISTER);
if (WORDS_BIG_ENDIAN && GET_MODE_SIZE (mode) > UNITS_PER_WORD
&& SCALAR_INT_MODE_P (mode))
return hard_regno_nregs[regno][mode] - 1;
return 0;
}
/* Like rtx_equal_p except that it allows a REG and a SUBREG to match
if they are the same hard reg, and has special hacks for
auto-increment and auto-decrement. This is specifically intended for
process_alt_operands to use in determining whether two operands
match. X is the operand whose number is the lower of the two.
It is supposed that X is the output operand and Y is the input
operand. Y_HARD_REGNO is the final hard regno of register Y or
register in subreg Y as we know it now. Otherwise, it is a
negative value. */
static bool
operands_match_p (rtx x, rtx y, int y_hard_regno)
{
int i;
RTX_CODE code = GET_CODE (x);
const char *fmt;
if (x == y)
return true;
if ((code == REG || (code == SUBREG && REG_P (SUBREG_REG (x))))
&& (REG_P (y) || (GET_CODE (y) == SUBREG && REG_P (SUBREG_REG (y)))))
{
int j;
i = get_hard_regno (x);
if (i < 0)
goto slow;
if ((j = y_hard_regno) < 0)
goto slow;
i += lra_constraint_offset (i, GET_MODE (x));
j += lra_constraint_offset (j, GET_MODE (y));
return i == j;
}
/* If two operands must match, because they are really a single
operand of an assembler insn, then two post-increments are invalid
because the assembler insn would increment only once. On the
other hand, a post-increment matches ordinary indexing if the
post-increment is the output operand. */
if (code == POST_DEC || code == POST_INC || code == POST_MODIFY)
return operands_match_p (XEXP (x, 0), y, y_hard_regno);
/* Two pre-increments are invalid because the assembler insn would
increment only once. On the other hand, a pre-increment matches
ordinary indexing if the pre-increment is the input operand. */
if (GET_CODE (y) == PRE_DEC || GET_CODE (y) == PRE_INC
|| GET_CODE (y) == PRE_MODIFY)
return operands_match_p (x, XEXP (y, 0), -1);
slow:
if (code == REG && GET_CODE (y) == SUBREG && REG_P (SUBREG_REG (y))
&& x == SUBREG_REG (y))
return true;
if (GET_CODE (y) == REG && code == SUBREG && REG_P (SUBREG_REG (x))
&& SUBREG_REG (x) == y)
return true;
/* Now we have disposed of all the cases in which different rtx
codes can match. */
if (code != GET_CODE (y))
return false;
/* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent. */
if (GET_MODE (x) != GET_MODE (y))
return false;
switch (code)
{
CASE_CONST_UNIQUE:
return false;
case LABEL_REF:
return LABEL_REF_LABEL (x) == LABEL_REF_LABEL (y);
case SYMBOL_REF:
return XSTR (x, 0) == XSTR (y, 0);
default:
break;
}
/* Compare the elements. If any pair of corresponding elements fail
to match, return false for the whole things. */
fmt = GET_RTX_FORMAT (code);
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
{
int val, j;
switch (fmt[i])
{
case 'w':
if (XWINT (x, i) != XWINT (y, i))
return false;
break;
case 'i':
if (XINT (x, i) != XINT (y, i))
return false;
break;
case 'e':
val = operands_match_p (XEXP (x, i), XEXP (y, i), -1);
if (val == 0)
return false;
break;
case '0':
break;
case 'E':
if (XVECLEN (x, i) != XVECLEN (y, i))
return false;
for (j = XVECLEN (x, i) - 1; j >= 0; --j)
{
val = operands_match_p (XVECEXP (x, i, j), XVECEXP (y, i, j), -1);
if (val == 0)
return false;
}
break;
/* It is believed that rtx's at this level will never
contain anything but integers and other rtx's, except for
within LABEL_REFs and SYMBOL_REFs. */
default:
gcc_unreachable ();
}
}
return true;
}
/* True if X is a constant that can be forced into the constant pool.
MODE is the mode of the operand, or VOIDmode if not known. */
#define CONST_POOL_OK_P(MODE, X) \
((MODE) != VOIDmode \
&& CONSTANT_P (X) \
&& GET_CODE (X) != HIGH \
&& !targetm.cannot_force_const_mem (MODE, X))
/* True if C is a non-empty register class that has too few registers
to be safely used as a reload target class. */
#define SMALL_REGISTER_CLASS_P(C) \
(ira_class_hard_regs_num [(C)] == 1 \
|| (ira_class_hard_regs_num [(C)] >= 1 \
&& targetm.class_likely_spilled_p (C)))
/* If REG is a reload pseudo, try to make its class satisfying CL. */
static void
narrow_reload_pseudo_class (rtx reg, enum reg_class cl)
{
enum reg_class rclass;
/* Do not make more accurate class from reloads generated. They are
mostly moves with a lot of constraints. Making more accurate
class may results in very narrow class and impossibility of find
registers for several reloads of one insn. */
if (INSN_UID (curr_insn) >= new_insn_uid_start)
return;
if (GET_CODE (reg) == SUBREG)
reg = SUBREG_REG (reg);
if (! REG_P (reg) || (int) REGNO (reg) < new_regno_start)
return;
if (in_class_p (reg, cl, &rclass) && rclass != cl)
lra_change_class (REGNO (reg), rclass, " Change to", true);
}
/* Generate reloads for matching OUT and INS (array of input operand
numbers with end marker -1) with reg class GOAL_CLASS. Add input
and output reloads correspondingly to the lists *BEFORE and *AFTER.
OUT might be negative. In this case we generate input reloads for
matched input operands INS. */
static void
match_reload (signed char out, signed char *ins, enum reg_class goal_class,
rtx_insn **before, rtx_insn **after)
{
int i, in;
rtx new_in_reg, new_out_reg, reg, clobber;
machine_mode inmode, outmode;
rtx in_rtx = *curr_id->operand_loc[ins[0]];
rtx out_rtx = out < 0 ? in_rtx : *curr_id->operand_loc[out];
inmode = curr_operand_mode[ins[0]];
outmode = out < 0 ? inmode : curr_operand_mode[out];
push_to_sequence (*before);
if (inmode != outmode)
{
if (GET_MODE_SIZE (inmode) > GET_MODE_SIZE (outmode))
{
reg = new_in_reg
= lra_create_new_reg_with_unique_value (inmode, in_rtx,
goal_class, "");
if (SCALAR_INT_MODE_P (inmode))
new_out_reg = gen_lowpart_SUBREG (outmode, reg);
else
new_out_reg = gen_rtx_SUBREG (outmode, reg, 0);
LRA_SUBREG_P (new_out_reg) = 1;
/* If the input reg is dying here, we can use the same hard
register for REG and IN_RTX. We do it only for original
pseudos as reload pseudos can die although original
pseudos still live where reload pseudos dies. */
if (REG_P (in_rtx) && (int) REGNO (in_rtx) < lra_new_regno_start
&& find_regno_note (curr_insn, REG_DEAD, REGNO (in_rtx)))
lra_assign_reg_val (REGNO (in_rtx), REGNO (reg));
}
else
{
reg = new_out_reg
= lra_create_new_reg_with_unique_value (outmode, out_rtx,
goal_class, "");
if (SCALAR_INT_MODE_P (outmode))
new_in_reg = gen_lowpart_SUBREG (inmode, reg);
else
new_in_reg = gen_rtx_SUBREG (inmode, reg, 0);
/* NEW_IN_REG is non-paradoxical subreg. We don't want
NEW_OUT_REG living above. We add clobber clause for
this. This is just a temporary clobber. We can remove
it at the end of LRA work. */
clobber = emit_clobber (new_out_reg);
LRA_TEMP_CLOBBER_P (PATTERN (clobber)) = 1;
LRA_SUBREG_P (new_in_reg) = 1;
if (GET_CODE (in_rtx) == SUBREG)
{
rtx subreg_reg = SUBREG_REG (in_rtx);
/* If SUBREG_REG is dying here and sub-registers IN_RTX
and NEW_IN_REG are similar, we can use the same hard
register for REG and SUBREG_REG. */
if (REG_P (subreg_reg)
&& (int) REGNO (subreg_reg) < lra_new_regno_start
&& GET_MODE (subreg_reg) == outmode
&& SUBREG_BYTE (in_rtx) == SUBREG_BYTE (new_in_reg)
&& find_regno_note (curr_insn, REG_DEAD, REGNO (subreg_reg)))
lra_assign_reg_val (REGNO (subreg_reg), REGNO (reg));
}
}
}
else
{
/* Pseudos have values -- see comments for lra_reg_info.
Different pseudos with the same value do not conflict even if
they live in the same place. When we create a pseudo we
assign value of original pseudo (if any) from which we
created the new pseudo. If we create the pseudo from the
input pseudo, the new pseudo will no conflict with the input
pseudo which is wrong when the input pseudo lives after the
insn and as the new pseudo value is changed by the insn
output. Therefore we create the new pseudo from the output.
We cannot reuse the current output register because we might
have a situation like "a <- a op b", where the constraints
force the second input operand ("b") to match the output
operand ("a"). "b" must then be copied into a new register
so that it doesn't clobber the current value of "a". */
new_in_reg = new_out_reg
= lra_create_new_reg_with_unique_value (outmode, out_rtx,
goal_class, "");
}
/* In operand can be got from transformations before processing insn
constraints. One example of such transformations is subreg
reloading (see function simplify_operand_subreg). The new
pseudos created by the transformations might have inaccurate
class (ALL_REGS) and we should make their classes more
accurate. */
narrow_reload_pseudo_class (in_rtx, goal_class);
lra_emit_move (copy_rtx (new_in_reg), in_rtx);
*before = get_insns ();
end_sequence ();
for (i = 0; (in = ins[i]) >= 0; i++)
{
lra_assert
(GET_MODE (*curr_id->operand_loc[in]) == VOIDmode
|| GET_MODE (new_in_reg) == GET_MODE (*curr_id->operand_loc[in]));
*curr_id->operand_loc[in] = new_in_reg;
}
lra_update_dups (curr_id, ins);
if (out < 0)
return;
/* See a comment for the input operand above. */
narrow_reload_pseudo_class (out_rtx, goal_class);
if (find_reg_note (curr_insn, REG_UNUSED, out_rtx) == NULL_RTX)
{
start_sequence ();
lra_emit_move (out_rtx, copy_rtx (new_out_reg));
emit_insn (*after);
*after = get_insns ();
end_sequence ();
}
*curr_id->operand_loc[out] = new_out_reg;
lra_update_dup (curr_id, out);
}
/* Return register class which is union of all reg classes in insn
constraint alternative string starting with P. */
static enum reg_class
reg_class_from_constraints (const char *p)
{
int c, len;
enum reg_class op_class = NO_REGS;
do
switch ((c = *p, len = CONSTRAINT_LEN (c, p)), c)
{
case '#':
case ',':
return op_class;
case 'g':
op_class = reg_class_subunion[op_class][GENERAL_REGS];
break;
default:
enum constraint_num cn = lookup_constraint (p);
enum reg_class cl = reg_class_for_constraint (cn);
if (cl == NO_REGS)
{
if (insn_extra_address_constraint (cn))
op_class
= (reg_class_subunion
[op_class][base_reg_class (VOIDmode, ADDR_SPACE_GENERIC,
ADDRESS, SCRATCH)]);
break;
}
op_class = reg_class_subunion[op_class][cl];
break;
}
while ((p += len), c);
return op_class;
}
/* If OP is a register, return the class of the register as per
get_reg_class, otherwise return NO_REGS. */
static inline enum reg_class
get_op_class (rtx op)
{
return REG_P (op) ? get_reg_class (REGNO (op)) : NO_REGS;
}
/* Return generated insn mem_pseudo:=val if TO_P or val:=mem_pseudo
otherwise. If modes of MEM_PSEUDO and VAL are different, use
SUBREG for VAL to make them equal. */
static rtx_insn *
emit_spill_move (bool to_p, rtx mem_pseudo, rtx val)
{
if (GET_MODE (mem_pseudo) != GET_MODE (val))
{
/* Usually size of mem_pseudo is greater than val size but in
rare cases it can be less as it can be defined by target
dependent macro HARD_REGNO_CALLER_SAVE_MODE. */
if (! MEM_P (val))
{
val = gen_rtx_SUBREG (GET_MODE (mem_pseudo),
GET_CODE (val) == SUBREG ? SUBREG_REG (val) : val,
0);
LRA_SUBREG_P (val) = 1;
}
else
{
mem_pseudo = gen_lowpart_SUBREG (GET_MODE (val), mem_pseudo);
LRA_SUBREG_P (mem_pseudo) = 1;
}
}
return as_a <rtx_insn *> (to_p
? gen_move_insn (mem_pseudo, val)
: gen_move_insn (val, mem_pseudo));
}
/* Process a special case insn (register move), return true if we
don't need to process it anymore. INSN should be a single set
insn. Set up that RTL was changed through CHANGE_P and macro
SECONDARY_MEMORY_NEEDED says to use secondary memory through
SEC_MEM_P. */
static bool
check_and_process_move (bool *change_p, bool *sec_mem_p ATTRIBUTE_UNUSED)
{
int sregno, dregno;
rtx dest, src, dreg, sreg, new_reg, scratch_reg;
rtx_insn *before;
enum reg_class dclass, sclass, secondary_class;
secondary_reload_info sri;
lra_assert (curr_insn_set != NULL_RTX);
dreg = dest = SET_DEST (curr_insn_set);
sreg = src = SET_SRC (curr_insn_set);
if (GET_CODE (dest) == SUBREG)
dreg = SUBREG_REG (dest);
if (GET_CODE (src) == SUBREG)
sreg = SUBREG_REG (src);
if (! (REG_P (dreg) || MEM_P (dreg)) || ! (REG_P (sreg) || MEM_P (sreg)))
return false;
sclass = dclass = NO_REGS;
if (REG_P (dreg))
dclass = get_reg_class (REGNO (dreg));
if (dclass == ALL_REGS)
/* ALL_REGS is used for new pseudos created by transformations
like reload of SUBREG_REG (see function
simplify_operand_subreg). We don't know their class yet. We
should figure out the class from processing the insn
constraints not in this fast path function. Even if ALL_REGS
were a right class for the pseudo, secondary_... hooks usually
are not define for ALL_REGS. */
return false;
if (REG_P (sreg))
sclass = get_reg_class (REGNO (sreg));
if (sclass == ALL_REGS)
/* See comments above. */
return false;
if (sclass == NO_REGS && dclass == NO_REGS)
return false;
#ifdef SECONDARY_MEMORY_NEEDED
if (SECONDARY_MEMORY_NEEDED (sclass, dclass, GET_MODE (src))
#ifdef SECONDARY_MEMORY_NEEDED_MODE
&& ((sclass != NO_REGS && dclass != NO_REGS)
|| GET_MODE (src) != SECONDARY_MEMORY_NEEDED_MODE (GET_MODE (src)))
#endif
)
{
*sec_mem_p = true;
return false;
}
#endif
if (! REG_P (dreg) || ! REG_P (sreg))
return false;
sri.prev_sri = NULL;
sri.icode = CODE_FOR_nothing;
sri.extra_cost = 0;
secondary_class = NO_REGS;
/* Set up hard register for a reload pseudo for hook
secondary_reload because some targets just ignore unassigned
pseudos in the hook. */
if (dclass != NO_REGS && lra_get_regno_hard_regno (REGNO (dreg)) < 0)
{
dregno = REGNO (dreg);
reg_renumber[dregno] = ira_class_hard_regs[dclass][0];
}
else
dregno = -1;
if (sclass != NO_REGS && lra_get_regno_hard_regno (REGNO (sreg)) < 0)
{
sregno = REGNO (sreg);
reg_renumber[sregno] = ira_class_hard_regs[sclass][0];
}
else
sregno = -1;
if (sclass != NO_REGS)
secondary_class
= (enum reg_class) targetm.secondary_reload (false, dest,
(reg_class_t) sclass,
GET_MODE (src), &sri);
if (sclass == NO_REGS
|| ((secondary_class != NO_REGS || sri.icode != CODE_FOR_nothing)
&& dclass != NO_REGS))
{
enum reg_class old_sclass = secondary_class;
secondary_reload_info old_sri = sri;
sri.prev_sri = NULL;
sri.icode = CODE_FOR_nothing;
sri.extra_cost = 0;
secondary_class
= (enum reg_class) targetm.secondary_reload (true, src,
(reg_class_t) dclass,
GET_MODE (src), &sri);
/* Check the target hook consistency. */
lra_assert
((secondary_class == NO_REGS && sri.icode == CODE_FOR_nothing)
|| (old_sclass == NO_REGS && old_sri.icode == CODE_FOR_nothing)
|| (secondary_class == old_sclass && sri.icode == old_sri.icode));
}
if (sregno >= 0)
reg_renumber [sregno] = -1;
if (dregno >= 0)
reg_renumber [dregno] = -1;
if (secondary_class == NO_REGS && sri.icode == CODE_FOR_nothing)
return false;
*change_p = true;
new_reg = NULL_RTX;
if (secondary_class != NO_REGS)
new_reg = lra_create_new_reg_with_unique_value (GET_MODE (src), NULL_RTX,
secondary_class,
"secondary");
start_sequence ();
if (sri.icode == CODE_FOR_nothing)
lra_emit_move (new_reg, src);
else
{
enum reg_class scratch_class;
scratch_class = (reg_class_from_constraints
(insn_data[sri.icode].operand[2].constraint));
scratch_reg = (lra_create_new_reg_with_unique_value
(insn_data[sri.icode].operand[2].mode, NULL_RTX,
scratch_class, "scratch"));
emit_insn (GEN_FCN (sri.icode) (new_reg != NULL_RTX ? new_reg : dest,
src, scratch_reg));
}
before = get_insns ();
end_sequence ();
lra_process_new_insns (curr_insn, before, NULL, "Inserting the move");
if (new_reg != NULL_RTX)
SET_SRC (curr_insn_set) = new_reg;
else
{
if (lra_dump_file != NULL)
{
fprintf (lra_dump_file, "Deleting move %u\n", INSN_UID (curr_insn));
dump_insn_slim (lra_dump_file, curr_insn);
}
lra_set_insn_deleted (curr_insn);
return true;
}
return false;
}
/* The following data describe the result of process_alt_operands.
The data are used in curr_insn_transform to generate reloads. */
/* The chosen reg classes which should be used for the corresponding
operands. */
static enum reg_class goal_alt[MAX_RECOG_OPERANDS];
/* True if the operand should be the same as another operand and that
other operand does not need a reload. */
static bool goal_alt_match_win[MAX_RECOG_OPERANDS];
/* True if the operand does not need a reload. */
static bool goal_alt_win[MAX_RECOG_OPERANDS];
/* True if the operand can be offsetable memory. */
static bool goal_alt_offmemok[MAX_RECOG_OPERANDS];
/* The number of an operand to which given operand can be matched to. */
static int goal_alt_matches[MAX_RECOG_OPERANDS];
/* The number of elements in the following array. */
static int goal_alt_dont_inherit_ops_num;
/* Numbers of operands whose reload pseudos should not be inherited. */
static int goal_alt_dont_inherit_ops[MAX_RECOG_OPERANDS];
/* True if the insn commutative operands should be swapped. */
static bool goal_alt_swapped;
/* The chosen insn alternative. */
static int goal_alt_number;
/* The following five variables are used to choose the best insn
alternative. They reflect final characteristics of the best
alternative. */
/* Number of necessary reloads and overall cost reflecting the
previous value and other unpleasantness of the best alternative. */
static int best_losers, best_overall;
/* Overall number hard registers used for reloads. For example, on
some targets we need 2 general registers to reload DFmode and only
one floating point register. */
static int best_reload_nregs;
/* Overall number reflecting distances of previous reloading the same
value. The distances are counted from the current BB start. It is
used to improve inheritance chances. */
static int best_reload_sum;
/* True if the current insn should have no correspondingly input or
output reloads. */
static bool no_input_reloads_p, no_output_reloads_p;
/* True if we swapped the commutative operands in the current
insn. */
static int curr_swapped;
/* if CHECK_ONLY_P is false, arrange for address element *LOC to be a
register of class CL. Add any input reloads to list BEFORE. AFTER
is nonnull if *LOC is an automodified value; handle that case by
adding the required output reloads to list AFTER. Return true if
the RTL was changed.
if CHECK_ONLY_P is true, check that the *LOC is a correct address
register. Return false if the address register is correct. */
static bool
process_addr_reg (rtx *loc, bool check_only_p, rtx_insn **before, rtx_insn **after,
enum reg_class cl)
{
int regno;
enum reg_class rclass, new_class;
rtx reg;
rtx new_reg;
machine_mode mode;
bool subreg_p, before_p = false;
subreg_p = GET_CODE (*loc) == SUBREG;
if (subreg_p)
loc = &SUBREG_REG (*loc);
reg = *loc;
mode = GET_MODE (reg);
if (! REG_P (reg))
{
if (check_only_p)
return true;
/* Always reload memory in an address even if the target supports
such addresses. */
new_reg = lra_create_new_reg_with_unique_value (mode, reg, cl, "address");
before_p = true;
}
else
{
regno = REGNO (reg);
rclass = get_reg_class (regno);
if (! check_only_p
&& (*loc = get_equiv_with_elimination (reg, curr_insn)) != reg)
{
if (lra_dump_file != NULL)
{
fprintf (lra_dump_file,
"Changing pseudo %d in address of insn %u on equiv ",
REGNO (reg), INSN_UID (curr_insn));
dump_value_slim (lra_dump_file, *loc, 1);
fprintf (lra_dump_file, "\n");
}
*loc = copy_rtx (*loc);
}
if (*loc != reg || ! in_class_p (reg, cl, &new_class))
{
if (check_only_p)
return true;
reg = *loc;
if (get_reload_reg (after == NULL ? OP_IN : OP_INOUT,
mode, reg, cl, subreg_p, "address", &new_reg))
before_p = true;
}
else if (new_class != NO_REGS && rclass != new_class)
{
if (check_only_p)
return true;
lra_change_class (regno, new_class, " Change to", true);
return false;
}
else
return false;
}
if (before_p)
{
push_to_sequence (*before);
lra_emit_move (new_reg, reg);
*before = get_insns ();
end_sequence ();
}
*loc = new_reg;
if (after != NULL)
{
start_sequence ();
lra_emit_move (before_p ? copy_rtx (reg) : reg, new_reg);
emit_insn (*after);
*after = get_insns ();
end_sequence ();
}
return true;
}
/* Insert move insn in simplify_operand_subreg. BEFORE returns
the insn to be inserted before curr insn. AFTER returns the
the insn to be inserted after curr insn. ORIGREG and NEWREG
are the original reg and new reg for reload. */
static void
insert_move_for_subreg (rtx_insn **before, rtx_insn **after, rtx origreg,
rtx newreg)
{
if (before)
{
push_to_sequence (*before);
lra_emit_move (newreg, origreg);
*before = get_insns ();
end_sequence ();
}
if (after)
{
start_sequence ();
lra_emit_move (origreg, newreg);
emit_insn (*after);
*after = get_insns ();
end_sequence ();
}
}
static int valid_address_p (machine_mode mode, rtx addr, addr_space_t as);
/* Make reloads for subreg in operand NOP with internal subreg mode
REG_MODE, add new reloads for further processing. Return true if
any change was done. */
static bool
simplify_operand_subreg (int nop, machine_mode reg_mode)
{
int hard_regno;
rtx_insn *before, *after;
machine_mode mode, innermode;
rtx reg, new_reg;
rtx operand = *curr_id->operand_loc[nop];
enum reg_class regclass;
enum op_type type;
before = after = NULL;
if (GET_CODE (operand) != SUBREG)
return false;
mode = GET_MODE (operand);
reg = SUBREG_REG (operand);
innermode = GET_MODE (reg);
type = curr_static_id->operand[nop].type;
/* If we change address for paradoxical subreg of memory, the
address might violate the necessary alignment or the access might
be slow. So take this into consideration. We should not worry
about access beyond allocated memory for paradoxical memory
subregs as we don't substitute such equiv memory (see processing
equivalences in function lra_constraints) and because for spilled
pseudos we allocate stack memory enough for the biggest
corresponding paradoxical subreg. */
if (MEM_P (reg)
&& (! SLOW_UNALIGNED_ACCESS (mode, MEM_ALIGN (reg))
|| MEM_ALIGN (reg) >= GET_MODE_ALIGNMENT (mode)))
{
rtx subst, old = *curr_id->operand_loc[nop];
alter_subreg (curr_id->operand_loc[nop], false);
subst = *curr_id->operand_loc[nop];
lra_assert (MEM_P (subst));
if (! valid_address_p (innermode, XEXP (reg, 0),
MEM_ADDR_SPACE (reg))
|| valid_address_p (GET_MODE (subst), XEXP (subst, 0),
MEM_ADDR_SPACE (subst)))
return true;
/* If the address was valid and became invalid, prefer to reload
the memory. Typical case is when the index scale should
correspond the memory. */
*curr_id->operand_loc[nop] = old;
}
else if (REG_P (reg) && REGNO (reg) < FIRST_PSEUDO_REGISTER)
{
alter_subreg (curr_id->operand_loc[nop], false);
return true;
}
else if (CONSTANT_P (reg))
{
/* Try to simplify subreg of constant. It is usually result of
equivalence substitution. */
if (innermode == VOIDmode
&& (innermode = original_subreg_reg_mode[nop]) == VOIDmode)
innermode = curr_static_id->operand[nop].mode;
if ((new_reg = simplify_subreg (mode, reg, innermode,
SUBREG_BYTE (operand))) != NULL_RTX)
{
*curr_id->operand_loc[nop] = new_reg;
return true;
}
}
/* Put constant into memory when we have mixed modes. It generates
a better code in most cases as it does not need a secondary
reload memory. It also prevents LRA looping when LRA is using
secondary reload memory again and again. */
if (CONSTANT_P (reg) && CONST_POOL_OK_P (reg_mode, reg)
&& SCALAR_INT_MODE_P (reg_mode) != SCALAR_INT_MODE_P (mode))
{
SUBREG_REG (operand) = force_const_mem (reg_mode, reg);
alter_subreg (curr_id->operand_loc[nop], false);
return true;
}
/* Force a reload of the SUBREG_REG if this is a constant or PLUS or
if there may be a problem accessing OPERAND in the outer
mode. */
if ((REG_P (reg)
&& REGNO (reg) >= FIRST_PSEUDO_REGISTER
&& (hard_regno = lra_get_regno_hard_regno (REGNO (reg))) >= 0
/* Don't reload paradoxical subregs because we could be looping
having repeatedly final regno out of hard regs range. */
&& (hard_regno_nregs[hard_regno][innermode]
>= hard_regno_nregs[hard_regno][mode])
&& simplify_subreg_regno (hard_regno, innermode,
SUBREG_BYTE (operand), mode) < 0
/* Don't reload subreg for matching reload. It is actually
valid subreg in LRA. */
&& ! LRA_SUBREG_P (operand))
|| CONSTANT_P (reg) || GET_CODE (reg) == PLUS || MEM_P (reg))
{
enum reg_class rclass;
if (REG_P (reg))
/* There is a big probability that we will get the same class
for the new pseudo and we will get the same insn which
means infinite looping. So spill the new pseudo. */
rclass = NO_REGS;
else
/* The class will be defined later in curr_insn_transform. */
rclass
= (enum reg_class) targetm.preferred_reload_class (reg, ALL_REGS);
if (get_reload_reg (curr_static_id->operand[nop].type, reg_mode, reg,
rclass, TRUE, "subreg reg", &new_reg))
{
bool insert_before, insert_after;
bitmap_set_bit (&lra_subreg_reload_pseudos, REGNO (new_reg));
insert_before = (type != OP_OUT
|| GET_MODE_SIZE (innermode) > GET_MODE_SIZE (mode));
insert_after = (type != OP_IN);
insert_move_for_subreg (insert_before ? &before : NULL,
insert_after ? &after : NULL,
reg, new_reg);
}
SUBREG_REG (operand) = new_reg;
lra_process_new_insns (curr_insn, before, after,
"Inserting subreg reload");
return true;
}
/* Force a reload for a paradoxical subreg. For paradoxical subreg,
IRA allocates hardreg to the inner pseudo reg according to its mode
instead of the outermode, so the size of the hardreg may not be enough
to contain the outermode operand, in that case we may need to insert
reload for the reg. For the following two types of paradoxical subreg,
we need to insert reload:
1. If the op_type is OP_IN, and the hardreg could not be paired with
other hardreg to contain the outermode operand
(checked by in_hard_reg_set_p), we need to insert the reload.
2. If the op_type is OP_OUT or OP_INOUT.
Here is a paradoxical subreg example showing how the reload is generated:
(insn 5 4 7 2 (set (reg:TI 106 [ __comp ])
(subreg:TI (reg:DI 107 [ __comp ]) 0)) {*movti_internal_rex64}
In IRA, reg107 is allocated to a DImode hardreg. We use x86-64 as example
here, if reg107 is assigned to hardreg R15, because R15 is the last
hardreg, compiler cannot find another hardreg to pair with R15 to
contain TImode data. So we insert a TImode reload reg180 for it.
After reload is inserted:
(insn 283 0 0 (set (subreg:DI (reg:TI 180 [orig:107 __comp ] [107]) 0)
(reg:DI 107 [ __comp ])) -1
(insn 5 4 7 2 (set (reg:TI 106 [ __comp ])
(subreg:TI (reg:TI 180 [orig:107 __comp ] [107]) 0)) {*movti_internal_rex64}
Two reload hard registers will be allocated to reg180 to save TImode data
in LRA_assign. */
else if (REG_P (reg)
&& REGNO (reg) >= FIRST_PSEUDO_REGISTER
&& (hard_regno = lra_get_regno_hard_regno (REGNO (reg))) >= 0
&& (hard_regno_nregs[hard_regno][innermode]
< hard_regno_nregs[hard_regno][mode])
&& (regclass = lra_get_allocno_class (REGNO (reg)))
&& (type != OP_IN
|| !in_hard_reg_set_p (reg_class_contents[regclass],
mode, hard_regno)))
{
/* The class will be defined later in curr_insn_transform. */
enum reg_class rclass
= (enum reg_class) targetm.preferred_reload_class (reg, ALL_REGS);
if (get_reload_reg (curr_static_id->operand[nop].type, mode, reg,
rclass, TRUE, "paradoxical subreg", &new_reg))
{
rtx subreg;
bool insert_before, insert_after;
PUT_MODE (new_reg, mode);
subreg = simplify_gen_subreg (innermode, new_reg, mode, 0);
bitmap_set_bit (&lra_subreg_reload_pseudos, REGNO (new_reg));
insert_before = (type != OP_OUT);
insert_after = (type != OP_IN);
insert_move_for_subreg (insert_before ? &before : NULL,
insert_after ? &after : NULL,
reg, subreg);
}
SUBREG_REG (operand) = new_reg;
lra_process_new_insns (curr_insn, before, after,
"Inserting paradoxical subreg reload");
return true;
}
return false;
}
/* Return TRUE if X refers for a hard register from SET. */
static bool
uses_hard_regs_p (rtx x, HARD_REG_SET set)
{
int i, j, x_hard_regno;
machine_mode mode;
const char *fmt;
enum rtx_code code;
if (x == NULL_RTX)
return false;
code = GET_CODE (x);
mode = GET_MODE (x);
if (code == SUBREG)
{
x = SUBREG_REG (x);
code = GET_CODE (x);
if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (mode))
mode = GET_MODE (x);
}
if (REG_P (x))
{
x_hard_regno = get_hard_regno (x);
return (x_hard_regno >= 0
&& overlaps_hard_reg_set_p (set, mode, x_hard_regno));
}
if (MEM_P (x))
{
struct address_info ad;
decompose_mem_address (&ad, x);
if (ad.base_term != NULL && uses_hard_regs_p (*ad.base_term, set))
return true;
if (ad.index_term != NULL && uses_hard_regs_p (*ad.index_term, set))
return true;
}
fmt = GET_RTX_FORMAT (code);
for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
{
if (fmt[i] == 'e')
{
if (uses_hard_regs_p (XEXP (x, i), set))
return true;
}
else if (fmt[i] == 'E')
{
for (j = XVECLEN (x, i) - 1; j >= 0; j--)
if (uses_hard_regs_p (XVECEXP (x, i, j), set))
return true;
}
}
return false;
}
/* Return true if OP is a spilled pseudo. */
static inline bool
spilled_pseudo_p (rtx op)
{
return (REG_P (op)
&& REGNO (op) >= FIRST_PSEUDO_REGISTER && in_mem_p (REGNO (op)));
}
/* Return true if X is a general constant. */
static inline bool
general_constant_p (rtx x)
{
return CONSTANT_P (x) && (! flag_pic || LEGITIMATE_PIC_OPERAND_P (x));
}
static bool
reg_in_class_p (rtx reg, enum reg_class cl)
{
if (cl == NO_REGS)
return get_reg_class (REGNO (reg)) == NO_REGS;
return in_class_p (reg, cl, NULL);
}
/* Return true if SET of RCLASS contains no hard regs which can be
used in MODE. */
static bool
prohibited_class_reg_set_mode_p (enum reg_class rclass,
HARD_REG_SET &set,
enum machine_mode mode)
{
HARD_REG_SET temp;
// ??? Is this assert right
// lra_assert (hard_reg_set_subset_p (set, reg_class_contents[rclass]));
COPY_HARD_REG_SET (temp, set);
AND_COMPL_HARD_REG_SET (temp, lra_no_alloc_regs);
return (hard_reg_set_subset_p
(temp, ira_prohibited_class_mode_regs[rclass][mode]));
}
/* Major function to choose the current insn alternative and what
operands should be reloaded and how. If ONLY_ALTERNATIVE is not
negative we should consider only this alternative. Return false if
we can not choose the alternative or find how to reload the
operands. */
static bool
process_alt_operands (int only_alternative)
{
bool ok_p = false;
int nop, overall, nalt;
int n_alternatives = curr_static_id->n_alternatives;
int n_operands = curr_static_id->n_operands;
/* LOSERS counts the operands that don't fit this alternative and
would require loading. */
int losers;
/* REJECT is a count of how undesirable this alternative says it is
if any reloading is required. If the alternative matches exactly
then REJECT is ignored, but otherwise it gets this much counted
against it in addition to the reloading needed. */
int reject;
int op_reject;
/* The number of elements in the following array. */
int early_clobbered_regs_num;
/* Numbers of operands which are early clobber registers. */
int early_clobbered_nops[MAX_RECOG_OPERANDS];
enum reg_class curr_alt[MAX_RECOG_OPERANDS];
HARD_REG_SET curr_alt_set[MAX_RECOG_OPERANDS];
bool curr_alt_match_win[MAX_RECOG_OPERANDS];
bool curr_alt_win[MAX_RECOG_OPERANDS];
bool curr_alt_offmemok[MAX_RECOG_OPERANDS];
int curr_alt_matches[MAX_RECOG_OPERANDS];
/* The number of elements in the following array. */
int curr_alt_dont_inherit_ops_num;
/* Numbers of operands whose reload pseudos should not be inherited. */
int curr_alt_dont_inherit_ops[MAX_RECOG_OPERANDS];
rtx op;
/* The register when the operand is a subreg of register, otherwise the
operand itself. */
rtx no_subreg_reg_operand[MAX_RECOG_OPERANDS];
/* The register if the operand is a register or subreg of register,
otherwise NULL. */
rtx operand_reg[MAX_RECOG_OPERANDS];
int hard_regno[MAX_RECOG_OPERANDS];
machine_mode biggest_mode[MAX_RECOG_OPERANDS];
int reload_nregs, reload_sum;
bool costly_p;
enum reg_class cl;
/* Calculate some data common for all alternatives to speed up the
function. */
for (nop = 0; nop < n_operands; nop++)
{
rtx reg;
op = no_subreg_reg_operand[nop] = *curr_id->operand_loc[nop];
/* The real hard regno of the operand after the allocation. */
hard_regno[nop] = get_hard_regno (op);
operand_reg[nop] = reg = op;
biggest_mode[nop] = GET_MODE (op);
if (GET_CODE (op) == SUBREG)
{
operand_reg[nop] = reg = SUBREG_REG (op);
if (GET_MODE_SIZE (biggest_mode[nop])
< GET_MODE_SIZE (GET_MODE (reg)))
biggest_mode[nop] = GET_MODE (reg);
}
if (! REG_P (reg))
operand_reg[nop] = NULL_RTX;
else if (REGNO (reg) >= FIRST_PSEUDO_REGISTER
|| ((int) REGNO (reg)
== lra_get_elimination_hard_regno (REGNO (reg))))
no_subreg_reg_operand[nop] = reg;
else
operand_reg[nop] = no_subreg_reg_operand[nop]
/* Just use natural mode for elimination result. It should
be enough for extra constraints hooks. */
= regno_reg_rtx[hard_regno[nop]];
}
/* The constraints are made of several alternatives. Each operand's
constraint looks like foo,bar,... with commas separating the
alternatives. The first alternatives for all operands go
together, the second alternatives go together, etc.
First loop over alternatives. */
alternative_mask preferred = curr_id->preferred_alternatives;
if (only_alternative >= 0)
preferred &= ALTERNATIVE_BIT (only_alternative);
for (nalt = 0; nalt < n_alternatives; nalt++)
{
/* Loop over operands for one constraint alternative. */
if (!TEST_BIT (preferred, nalt))
continue;
overall = losers = reject = reload_nregs = reload_sum = 0;
for (nop = 0; nop < n_operands; nop++)
{
int inc = (curr_static_id
->operand_alternative[nalt * n_operands + nop].reject);
if (lra_dump_file != NULL && inc != 0)
fprintf (lra_dump_file,
" Staticly defined alt reject+=%d\n", inc);
reject += inc;
}
early_clobbered_regs_num = 0;
for (nop = 0; nop < n_operands; nop++)
{
const char *p;
char *end;
int len, c, m, i, opalt_num, this_alternative_matches;
bool win, did_match, offmemok, early_clobber_p;
/* false => this operand can be reloaded somehow for this
alternative. */
bool badop;
/* true => this operand can be reloaded if the alternative
allows regs. */
bool winreg;
/* True if a constant forced into memory would be OK for
this operand. */
bool constmemok;
enum reg_class this_alternative, this_costly_alternative;
HARD_REG_SET this_alternative_set, this_costly_alternative_set;
bool this_alternative_match_win, this_alternative_win;
bool this_alternative_offmemok;
bool scratch_p;
machine_mode mode;
enum constraint_num cn;
opalt_num = nalt * n_operands + nop;
if (curr_static_id->operand_alternative[opalt_num].anything_ok)
{
/* Fast track for no constraints at all. */
curr_alt[nop] = NO_REGS;
CLEAR_HARD_REG_SET (curr_alt_set[nop]);
curr_alt_win[nop] = true;
curr_alt_match_win[nop] = false;
curr_alt_offmemok[nop] = false;
curr_alt_matches[nop] = -1;
continue;
}
op = no_subreg_reg_operand[nop];
mode = curr_operand_mode[nop];
win = did_match = winreg = offmemok = constmemok = false;
badop = true;
early_clobber_p = false;
p = curr_static_id->operand_alternative[opalt_num].constraint;
this_costly_alternative = this_alternative = NO_REGS;
/* We update set of possible hard regs besides its class
because reg class might be inaccurate. For example,
union of LO_REGS (l), HI_REGS(h), and STACK_REG(k) in ARM
is translated in HI_REGS because classes are merged by
pairs and there is no accurate intermediate class. */
CLEAR_HARD_REG_SET (this_alternative_set);
CLEAR_HARD_REG_SET (this_costly_alternative_set);
this_alternative_win = false;
this_alternative_match_win = false;
this_alternative_offmemok = false;
this_alternative_matches = -1;
/* An empty constraint should be excluded by the fast
track. */
lra_assert (*p != 0 && *p != ',');
op_reject = 0;
/* Scan this alternative's specs for this operand; set WIN
if the operand fits any letter in this alternative.
Otherwise, clear BADOP if this operand could fit some
letter after reloads, or set WINREG if this operand could
fit after reloads provided the constraint allows some
registers. */
costly_p = false;
do
{
switch ((c = *p, len = CONSTRAINT_LEN (c, p)), c)
{
case '\0':
len = 0;
break;
case ',':
c = '\0';
break;
case '&':
early_clobber_p = true;
break;
case '$':
op_reject += LRA_MAX_REJECT;
break;
case '^':
op_reject += LRA_LOSER_COST_FACTOR;
break;
case '#':
/* Ignore rest of this alternative. */
c = '\0';
break;
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
{
int m_hregno;
bool match_p;
m = strtoul (p, &end, 10);
p = end;
len = 0;
lra_assert (nop > m);
this_alternative_matches = m;
m_hregno = get_hard_regno (*curr_id->operand_loc[m]);
/* We are supposed to match a previous operand.
If we do, we win if that one did. If we do
not, count both of the operands as losers.
(This is too conservative, since most of the
time only a single reload insn will be needed
to make the two operands win. As a result,
this alternative may be rejected when it is
actually desirable.) */
match_p = false;
if (operands_match_p (*curr_id->operand_loc[nop],
*curr_id->operand_loc[m], m_hregno))
{
/* We should reject matching of an early
clobber operand if the matching operand is
not dying in the insn. */
if (! curr_static_id->operand[m].early_clobber
|| operand_reg[nop] == NULL_RTX
|| (find_regno_note (curr_insn, REG_DEAD,
REGNO (op))
|| REGNO (op) == REGNO (operand_reg[m])))
match_p = true;
}
if (match_p)
{
/* If we are matching a non-offsettable
address where an offsettable address was
expected, then we must reject this
combination, because we can't reload
it. */
if (curr_alt_offmemok[m]
&& MEM_P (*curr_id->operand_loc[m])
&& curr_alt[m] == NO_REGS && ! curr_alt_win[m])
continue;
}
else
{
/* Operands don't match. Both operands must
allow a reload register, otherwise we
cannot make them match. */
if (curr_alt[m] == NO_REGS)
break;
/* Retroactively mark the operand we had to
match as a loser, if it wasn't already and
it wasn't matched to a register constraint
(e.g it might be matched by memory). */
if (curr_alt_win[m]
&& (operand_reg[m] == NULL_RTX
|| hard_regno[m] < 0))
{
losers++;
reload_nregs
+= (ira_reg_class_max_nregs[curr_alt[m]]
[GET_MODE (*curr_id->operand_loc[m])]);
}
/* Prefer matching earlyclobber alternative as
it results in less hard regs required for
the insn than a non-matching earlyclobber
alternative. */
if (curr_static_id->operand[m].early_clobber)
{
if (lra_dump_file != NULL)
fprintf
(lra_dump_file,
" %d Matching earlyclobber alt:"
" reject--\n",
nop);
reject--;
}
/* Otherwise we prefer no matching
alternatives because it gives more freedom
in RA. */
else if (operand_reg[nop] == NULL_RTX
|| (find_regno_note (curr_insn, REG_DEAD,
REGNO (operand_reg[nop]))
== NULL_RTX))
{
if (lra_dump_file != NULL)
fprintf
(lra_dump_file,
" %d Matching alt: reject+=2\n",
nop);
reject += 2;
}
}
/* If we have to reload this operand and some
previous operand also had to match the same
thing as this operand, we don't know how to do
that. */
if (!match_p || !curr_alt_win[m])
{
for (i = 0; i < nop; i++)
if (curr_alt_matches[i] == m)
break;
if (i < nop)
break;
}
else
did_match = true;
/* This can be fixed with reloads if the operand
we are supposed to match can be fixed with
reloads. */
badop = false;
this_alternative = curr_alt[m];
COPY_HARD_REG_SET (this_alternative_set, curr_alt_set[m]);
winreg = this_alternative != NO_REGS;
break;
}
case 'g':
if (MEM_P (op)
|| general_constant_p (op)
|| spilled_pseudo_p (op))
win = true;
cl = GENERAL_REGS;
goto reg;
default:
cn = lookup_constraint (p);
switch (get_constraint_type (cn))
{
case CT_REGISTER:
cl = reg_class_for_constraint (cn);
if (cl != NO_REGS)
goto reg;
break;
case CT_CONST_INT:
if (CONST_INT_P (op)
&& insn_const_int_ok_for_constraint (INTVAL (op), cn))
win = true;
break;
case CT_MEMORY:
if (MEM_P (op)
&& satisfies_memory_constraint_p (op, cn))
win = true;
else if (spilled_pseudo_p (op))
win = true;
/* If we didn't already win, we can reload constants
via force_const_mem or put the pseudo value into
memory, or make other memory by reloading the
address like for 'o'. */
if (CONST_POOL_OK_P (mode, op)
|| MEM_P (op) || REG_P (op))
badop = false;
constmemok = true;
offmemok = true;
break;
case CT_ADDRESS:
/* If we didn't already win, we can reload the address
into a base register. */
if (satisfies_address_constraint_p (op, cn))
win = true;
cl = base_reg_class (VOIDmode, ADDR_SPACE_GENERIC,
ADDRESS, SCRATCH);
badop = false;
goto reg;
case CT_FIXED_FORM:
if (constraint_satisfied_p (op, cn))
win = true;
break;
}
break;
reg:
this_alternative = reg_class_subunion[this_alternative][cl];
IOR_HARD_REG_SET (this_alternative_set,
reg_class_contents[cl]);
if (costly_p)
{
this_costly_alternative
= reg_class_subunion[this_costly_alternative][cl];
IOR_HARD_REG_SET (this_costly_alternative_set,
reg_class_contents[cl]);
}
if (mode == BLKmode)
break;
winreg = true;
if (REG_P (op))
{
if (hard_regno[nop] >= 0
&& in_hard_reg_set_p (this_alternative_set,
mode, hard_regno[nop]))
win = true;
else if (hard_regno[nop] < 0
&& in_class_p (op, this_alternative, NULL))
win = true;
}
break;
}
if (c != ' ' && c != '\t')
costly_p = c == '*';
}
while ((p += len), c);
scratch_p = (operand_reg[nop] != NULL_RTX
&& lra_former_scratch_p (REGNO (operand_reg[nop])));
/* Record which operands fit this alternative. */
if (win)
{
this_alternative_win = true;
if (operand_reg[nop] != NULL_RTX)
{
if (hard_regno[nop] >= 0)
{
if (in_hard_reg_set_p (this_costly_alternative_set,
mode, hard_regno[nop]))
{
if (lra_dump_file != NULL)
fprintf (lra_dump_file,
" %d Costly set: reject++\n",
nop);
reject++;
}
}
else
{
/* Prefer won reg to spilled pseudo under other
equal conditions for possibe inheritance. */
if (! scratch_p)
{
if (lra_dump_file != NULL)
fprintf
(lra_dump_file,
" %d Non pseudo reload: reject++\n",
nop);
reject++;
}
if (in_class_p (operand_reg[nop],
this_costly_alternative, NULL))
{
if (lra_dump_file != NULL)
fprintf
(lra_dump_file,
" %d Non pseudo costly reload:"
" reject++\n",
nop);
reject++;
}
}
/* We simulate the behaviour of old reload here.
Although scratches need hard registers and it
might result in spilling other pseudos, no reload
insns are generated for the scratches. So it
might cost something but probably less than old
reload pass believes. */
if (scratch_p)
{
if (lra_dump_file != NULL)
fprintf (lra_dump_file,
" %d Scratch win: reject+=2\n",
nop);
reject += 2;
}
}
}
else if (did_match)
this_alternative_match_win = true;
else
{
int const_to_mem = 0;
bool no_regs_p;
reject += op_reject;
/* Never do output reload of stack pointer. It makes
impossible to do elimination when SP is changed in
RTL. */
if (op == stack_pointer_rtx && ! frame_pointer_needed
&& curr_static_id->operand[nop].type != OP_IN)
goto fail;
/* If this alternative asks for a specific reg class, see if there
is at least one allocatable register in that class. */
no_regs_p
= (this_alternative == NO_REGS
|| (hard_reg_set_subset_p
(reg_class_contents[this_alternative],
lra_no_alloc_regs)));
/* For asms, verify that the class for this alternative is possible
for the mode that is specified. */
if (!no_regs_p && INSN_CODE (curr_insn) < 0)
{
int i;
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
if (HARD_REGNO_MODE_OK (i, mode)
&& in_hard_reg_set_p (reg_class_contents[this_alternative],
mode, i))
break;
if (i == FIRST_PSEUDO_REGISTER)
winreg = false;
}
/* If this operand accepts a register, and if the
register class has at least one allocatable register,
then this operand can be reloaded. */
if (winreg && !no_regs_p)
badop = false;
if (badop)
{
if (lra_dump_file != NULL)
fprintf (lra_dump_file,
" alt=%d: Bad operand -- refuse\n",
nalt);
goto fail;
}
/* If not assigned pseudo has a class which a subset of
required reg class, it is a less costly alternative
as the pseudo still can get a hard reg of necessary
class. */
if (! no_regs_p && REG_P (op) && hard_regno[nop] < 0
&& (cl = get_reg_class (REGNO (op))) != NO_REGS
&& ira_class_subset_p[this_alternative][cl])
{
if (lra_dump_file != NULL)
fprintf
(lra_dump_file,
" %d Super set class reg: reject-=3\n", nop);
reject -= 3;
}
this_alternative_offmemok = offmemok;
if (this_costly_alternative != NO_REGS)
{
if (lra_dump_file != NULL)
fprintf (lra_dump_file,
" %d Costly loser: reject++\n", nop);
reject++;
}
/* If the operand is dying, has a matching constraint,
and satisfies constraints of the matched operand
which failed to satisfy the own constraints, most probably
the reload for this operand will be gone. */
if (this_alternative_matches >= 0
&& !curr_alt_win[this_alternative_matches]
&& REG_P (op)
&& find_regno_note (curr_insn, REG_DEAD, REGNO (op))
&& (hard_regno[nop] >= 0
? in_hard_reg_set_p (this_alternative_set,
mode, hard_regno[nop])
: in_class_p (op, this_alternative, NULL)))
{
if (lra_dump_file != NULL)
fprintf
(lra_dump_file,
" %d Dying matched operand reload: reject++\n",
nop);
reject++;
}
else
{
/* Strict_low_part requires to reload the register
not the sub-register. In this case we should
check that a final reload hard reg can hold the
value mode. */
if (curr_static_id->operand[nop].strict_low
&& REG_P (op)
&& hard_regno[nop] < 0
&& GET_CODE (*curr_id->operand_loc[nop]) == SUBREG
&& ira_class_hard_regs_num[this_alternative] > 0
&& ! HARD_REGNO_MODE_OK (ira_class_hard_regs
[this_alternative][0],
GET_MODE
(*curr_id->operand_loc[nop])))
{
if (lra_dump_file != NULL)
fprintf
(lra_dump_file,
" alt=%d: Strict low subreg reload -- refuse\n",
nalt);
goto fail;
}
losers++;
}
if (operand_reg[nop] != NULL_RTX
/* Output operands and matched input operands are
not inherited. The following conditions do not
exactly describe the previous statement but they
are pretty close. */
&& curr_static_id->operand[nop].type != OP_OUT
&& (this_alternative_matches < 0
|| curr_static_id->operand[nop].type != OP_IN))
{
int last_reload = (lra_reg_info[ORIGINAL_REGNO
(operand_reg[nop])]
.last_reload);
/* The value of reload_sum has sense only if we
process insns in their order. It happens only on
the first constraints sub-pass when we do most of
reload work. */
if (lra_constraint_iter == 1 && last_reload > bb_reload_num)
reload_sum += last_reload - bb_reload_num;
}
/* If this is a constant that is reloaded into the
desired class by copying it to memory first, count
that as another reload. This is consistent with
other code and is required to avoid choosing another
alternative when the constant is moved into memory.
Note that the test here is precisely the same as in
the code below that calls force_const_mem. */
if (CONST_POOL_OK_P (mode, op)
&& ((targetm.preferred_reload_class
(op, this_alternative) == NO_REGS)
|| no_input_reloads_p))
{
const_to_mem = 1;
if (! no_regs_p)
losers++;
}
/* Alternative loses if it requires a type of reload not
permitted for this insn. We can always reload
objects with a REG_UNUSED note. */
if ((curr_static_id->operand[nop].type != OP_IN
&& no_output_reloads_p
&& ! find_reg_note (curr_insn, REG_UNUSED, op))
|| (curr_static_id->operand[nop].type != OP_OUT
&& no_input_reloads_p && ! const_to_mem)
|| (this_alternative_matches >= 0
&& (no_input_reloads_p
|| (no_output_reloads_p
&& (curr_static_id->operand
[this_alternative_matches].type != OP_IN)
&& ! find_reg_note (curr_insn, REG_UNUSED,
no_subreg_reg_operand
[this_alternative_matches])))))
{
if (lra_dump_file != NULL)
fprintf
(lra_dump_file,
" alt=%d: No input/otput reload -- refuse\n",
nalt);
goto fail;
}
/* Alternative loses if it required class pseudo can not
hold value of required mode. Such insns can be
described by insn definitions with mode iterators. */
if (GET_MODE (*curr_id->operand_loc[nop]) != VOIDmode
&& ! hard_reg_set_empty_p (this_alternative_set)
/* It is common practice for constraints to use a
class which does not have actually enough regs to
hold the value (e.g. x86 AREG for mode requiring
more one general reg). Therefore we have 2
conditions to check that the reload pseudo can
not hold the mode value. */
&& ! HARD_REGNO_MODE_OK (ira_class_hard_regs
[this_alternative][0],
GET_MODE (*curr_id->operand_loc[nop]))
/* The above condition is not enough as the first
reg in ira_class_hard_regs can be not aligned for
multi-words mode values. */
&& (prohibited_class_reg_set_mode_p
(this_alternative, this_alternative_set,
GET_MODE (*curr_id->operand_loc[nop]))))
{
if (lra_dump_file != NULL)
fprintf (lra_dump_file,
" alt=%d: reload pseudo for op %d "
" can not hold the mode value -- refuse\n",
nalt, nop);
goto fail;
}
/* Check strong discouragement of reload of non-constant
into class THIS_ALTERNATIVE. */
if (! CONSTANT_P (op) && ! no_regs_p
&& (targetm.preferred_reload_class
(op, this_alternative) == NO_REGS
|| (curr_static_id->operand[nop].type == OP_OUT
&& (targetm.preferred_output_reload_class
(op, this_alternative) == NO_REGS))))
{
if (lra_dump_file != NULL)
fprintf (lra_dump_file,
" %d Non-prefered reload: reject+=%d\n",
nop, LRA_MAX_REJECT);
reject += LRA_MAX_REJECT;
}
if (! (MEM_P (op) && offmemok)
&& ! (const_to_mem && constmemok))
{
/* We prefer to reload pseudos over reloading other
things, since such reloads may be able to be
eliminated later. So bump REJECT in other cases.
Don't do this in the case where we are forcing a
constant into memory and it will then win since
we don't want to have a different alternative
match then. */
if (! (REG_P (op) && REGNO (op) >= FIRST_PSEUDO_REGISTER))
{
if (lra_dump_file != NULL)
fprintf
(lra_dump_file,
" %d Non-pseudo reload: reject+=2\n",
nop);
reject += 2;
}
if (! no_regs_p)
reload_nregs
+= ira_reg_class_max_nregs[this_alternative][mode];
if (SMALL_REGISTER_CLASS_P (this_alternative))
{
if (lra_dump_file != NULL)
fprintf
(lra_dump_file,
" %d Small class reload: reject+=%d\n",
nop, LRA_LOSER_COST_FACTOR / 2);
reject += LRA_LOSER_COST_FACTOR / 2;
}
}
/* We are trying to spill pseudo into memory. It is
usually more costly than moving to a hard register
although it might takes the same number of
reloads. */
if (no_regs_p && REG_P (op) && hard_regno[nop] >= 0)
{
if (lra_dump_file != NULL)
fprintf
(lra_dump_file,
" %d Spill pseudo into memory: reject+=3\n",
nop);
reject += 3;
if (VECTOR_MODE_P (mode))
{
/* Spilling vectors into memory is usually more
costly as they contain big values. */
if (lra_dump_file != NULL)
fprintf
(lra_dump_file,
" %d Spill vector pseudo: reject+=2\n",
nop);
reject += 2;
}
}
#ifdef SECONDARY_MEMORY_NEEDED
/* If reload requires moving value through secondary
memory, it will need one more insn at least. */
if (this_alternative != NO_REGS
&& REG_P (op) && (cl = get_reg_class (REGNO (op))) != NO_REGS
&& ((curr_static_id->operand[nop].type != OP_OUT
&& SECONDARY_MEMORY_NEEDED (cl, this_alternative,
GET_MODE (op)))
|| (curr_static_id->operand[nop].type != OP_IN
&& SECONDARY_MEMORY_NEEDED (this_alternative, cl,
GET_MODE (op)))))
losers++;
#endif
/* Input reloads can be inherited more often than output
reloads can be removed, so penalize output
reloads. */
if (!REG_P (op) || curr_static_id->operand[nop].type != OP_IN)
{
if (lra_dump_file != NULL)
fprintf
(lra_dump_file,
" %d Non input pseudo reload: reject++\n",
nop);
reject++;
}
}
if (early_clobber_p && ! scratch_p)
{
if (lra_dump_file != NULL)
fprintf (lra_dump_file,
" %d Early clobber: reject++\n", nop);
reject++;
}
/* ??? We check early clobbers after processing all operands
(see loop below) and there we update the costs more.
Should we update the cost (may be approximately) here
because of early clobber register reloads or it is a rare
or non-important thing to be worth to do it. */
overall = losers * LRA_LOSER_COST_FACTOR + reject;
if ((best_losers == 0 || losers != 0) && best_overall < overall)
{
if (lra_dump_file != NULL)
fprintf (lra_dump_file,
" alt=%d,overall=%d,losers=%d -- refuse\n",
nalt, overall, losers);
goto fail;
}
curr_alt[nop] = this_alternative;
COPY_HARD_REG_SET (curr_alt_set[nop], this_alternative_set);
curr_alt_win[nop] = this_alternative_win;
curr_alt_match_win[nop] = this_alternative_match_win;
curr_alt_offmemok[nop] = this_alternative_offmemok;
curr_alt_matches[nop] = this_alternative_matches;
if (this_alternative_matches >= 0
&& !did_match && !this_alternative_win)
curr_alt_win[this_alternative_matches] = false;
if (early_clobber_p && operand_reg[nop] != NULL_RTX)
early_clobbered_nops[early_clobbered_regs_num++] = nop;
}
if (curr_insn_set != NULL_RTX && n_operands == 2
/* Prevent processing non-move insns. */
&& (GET_CODE (SET_SRC (curr_insn_set)) == SUBREG
|| SET_SRC (curr_insn_set) == no_subreg_reg_operand[1])
&& ((! curr_alt_win[0] && ! curr_alt_win[1]
&& REG_P (no_subreg_reg_operand[0])
&& REG_P (no_subreg_reg_operand[1])
&& (reg_in_class_p (no_subreg_reg_operand[0], curr_alt[1])
|| reg_in_class_p (no_subreg_reg_operand[1], curr_alt[0])))
|| (! curr_alt_win[0] && curr_alt_win[1]
&& REG_P (no_subreg_reg_operand[1])
&& reg_in_class_p (no_subreg_reg_operand[1], curr_alt[0]))
|| (curr_alt_win[0] && ! curr_alt_win[1]
&& REG_P (no_subreg_reg_operand[0])
&& reg_in_class_p (no_subreg_reg_operand[0], curr_alt[1])
&& (! CONST_POOL_OK_P (curr_operand_mode[1],
no_subreg_reg_operand[1])
|| (targetm.preferred_reload_class
(no_subreg_reg_operand[1],
(enum reg_class) curr_alt[1]) != NO_REGS))
/* If it is a result of recent elimination in move
insn we can transform it into an add still by
using this alternative. */
&& GET_CODE (no_subreg_reg_operand[1]) != PLUS)))
{
/* We have a move insn and a new reload insn will be similar
to the current insn. We should avoid such situation as it
results in LRA cycling. */
overall += LRA_MAX_REJECT;
}
ok_p = true;
curr_alt_dont_inherit_ops_num = 0;
for (nop = 0; nop < early_clobbered_regs_num; nop++)
{
int i, j, clobbered_hard_regno, first_conflict_j, last_conflict_j;
HARD_REG_SET temp_set;
i = early_clobbered_nops[nop];
if ((! curr_alt_win[i] && ! curr_alt_match_win[i])
|| hard_regno[i] < 0)
continue;
lra_assert (operand_reg[i] != NULL_RTX);
clobbered_hard_regno = hard_regno[i];
CLEAR_HARD_REG_SET (temp_set);
add_to_hard_reg_set (&temp_set, biggest_mode[i], clobbered_hard_regno);
first_conflict_j = last_conflict_j = -1;
for (j = 0; j < n_operands; j++)
if (j == i
/* We don't want process insides of match_operator and
match_parallel because otherwise we would process
their operands once again generating a wrong
code. */
|| curr_static_id->operand[j].is_operator)
continue;
else if ((curr_alt_matches[j] == i && curr_alt_match_win[j])
|| (curr_alt_matches[i] == j && curr_alt_match_win[i]))
continue;
/* If we don't reload j-th operand, check conflicts. */
else if ((curr_alt_win[j] || curr_alt_match_win[j])
&& uses_hard_regs_p (*curr_id->operand_loc[j], temp_set))
{
if (first_conflict_j < 0)
first_conflict_j = j;
last_conflict_j = j;
}
if (last_conflict_j < 0)
continue;
/* If earlyclobber operand conflicts with another
non-matching operand which is actually the same register
as the earlyclobber operand, it is better to reload the
another operand as an operand matching the earlyclobber
operand can be also the same. */
if (first_conflict_j == last_conflict_j
&& operand_reg[last_conflict_j]
!= NULL_RTX && ! curr_alt_match_win[last_conflict_j]
&& REGNO (operand_reg[i]) == REGNO (operand_reg[last_conflict_j]))
{
curr_alt_win[last_conflict_j] = false;
curr_alt_dont_inherit_ops[curr_alt_dont_inherit_ops_num++]
= last_conflict_j;
losers++;
/* Early clobber was already reflected in REJECT. */
lra_assert (reject > 0);
if (lra_dump_file != NULL)
fprintf
(lra_dump_file,
" %d Conflict early clobber reload: reject--\n",
i);
reject--;
overall += LRA_LOSER_COST_FACTOR - 1;
}
else
{
/* We need to reload early clobbered register and the
matched registers. */
for (j = 0; j < n_operands; j++)
if (curr_alt_matches[j] == i)
{
curr_alt_match_win[j] = false;
losers++;
overall += LRA_LOSER_COST_FACTOR;
}
if (! curr_alt_match_win[i])
curr_alt_dont_inherit_ops[curr_alt_dont_inherit_ops_num++] = i;
else
{
/* Remember pseudos used for match reloads are never
inherited. */
lra_assert (curr_alt_matches[i] >= 0);
curr_alt_win[curr_alt_matches[i]] = false;
}
curr_alt_win[i] = curr_alt_match_win[i] = false;
losers++;
/* Early clobber was already reflected in REJECT. */
lra_assert (reject > 0);
if (lra_dump_file != NULL)
fprintf
(lra_dump_file,
" %d Matched conflict early clobber reloads:"
"reject--\n",
i);
reject--;
overall += LRA_LOSER_COST_FACTOR - 1;
}
}
if (lra_dump_file != NULL)
fprintf (lra_dump_file, " alt=%d,overall=%d,losers=%d,rld_nregs=%d\n",
nalt, overall, losers, reload_nregs);
/* If this alternative can be made to work by reloading, and it
needs less reloading than the others checked so far, record
it as the chosen goal for reloading. */
if ((best_losers != 0 && losers == 0)
|| (((best_losers == 0 && losers == 0)
|| (best_losers != 0 && losers != 0))
&& (best_overall > overall
|| (best_overall == overall
/* If the cost of the reloads is the same,
prefer alternative which requires minimal
number of reload regs. */
&& (reload_nregs < best_reload_nregs
|| (reload_nregs == best_reload_nregs
&& (best_reload_sum < reload_sum
|| (best_reload_sum == reload_sum
&& nalt < goal_alt_number))))))))
{
for (nop = 0; nop < n_operands; nop++)
{
goal_alt_win[nop] = curr_alt_win[nop];
goal_alt_match_win[nop] = curr_alt_match_win[nop];
goal_alt_matches[nop] = curr_alt_matches[nop];
goal_alt[nop] = curr_alt[nop];
goal_alt_offmemok[nop] = curr_alt_offmemok[nop];
}
goal_alt_dont_inherit_ops_num = curr_alt_dont_inherit_ops_num;
for (nop = 0; nop < curr_alt_dont_inherit_ops_num; nop++)
goal_alt_dont_inherit_ops[nop] = curr_alt_dont_inherit_ops[nop];
goal_alt_swapped = curr_swapped;
best_overall = overall;
best_losers = losers;
best_reload_nregs = reload_nregs;
best_reload_sum = reload_sum;
goal_alt_number = nalt;
}
if (losers == 0)
/* Everything is satisfied. Do not process alternatives
anymore. */
break;
fail:
;
}
return ok_p;
}
/* Make reload base reg from address AD. */
static rtx
base_to_reg (struct address_info *ad)
{
enum reg_class cl;
int code = -1;
rtx new_inner = NULL_RTX;
rtx new_reg = NULL_RTX;
rtx_insn *insn;
rtx_insn *last_insn = get_last_insn();
lra_assert (ad->base == ad->base_term && ad->disp == ad->disp_term);
cl = base_reg_class (ad->mode, ad->as, ad->base_outer_code,
get_index_code (ad));
new_reg = lra_create_new_reg (GET_MODE (*ad->base_term), NULL_RTX,
cl, "base");
new_inner = simplify_gen_binary (PLUS, GET_MODE (new_reg), new_reg,
ad->disp_term == NULL
? gen_int_mode (0, ad->mode)
: *ad->disp_term);
if (!valid_address_p (ad->mode, new_inner, ad->as))
return NULL_RTX;
insn = emit_insn (gen_rtx_SET (ad->mode, new_reg, *ad->base_term));
code = recog_memoized (insn);
if (code < 0)
{
delete_insns_since (last_insn);
return NULL_RTX;
}
return new_inner;
}
/* Make reload base reg + disp from address AD. Return the new pseudo. */
static rtx
base_plus_disp_to_reg (struct address_info *ad)
{
enum reg_class cl;
rtx new_reg;
lra_assert (ad->base == ad->base_term && ad->disp == ad->disp_term);
cl = base_reg_class (ad->mode, ad->as, ad->base_outer_code,
get_index_code (ad));
new_reg = lra_create_new_reg (GET_MODE (*ad->base_term), NULL_RTX,
cl, "base + disp");
lra_emit_add (new_reg, *ad->base_term, *ad->disp_term);
return new_reg;
}
/* Make reload of index part of address AD. Return the new
pseudo. */
static rtx
index_part_to_reg (struct address_info *ad)
{
rtx new_reg;
new_reg = lra_create_new_reg (GET_MODE (*ad->index), NULL_RTX,
INDEX_REG_CLASS, "index term");
expand_mult (GET_MODE (*ad->index), *ad->index_term,
GEN_INT (get_index_scale (ad)), new_reg, 1);
return new_reg;
}
/* Return true if we can add a displacement to address AD, even if that
makes the address invalid. The fix-up code requires any new address
to be the sum of the BASE_TERM, INDEX and DISP_TERM fields. */
static bool
can_add_disp_p (struct address_info *ad)
{
return (!ad->autoinc_p
&& ad->segment == NULL
&& ad->base == ad->base_term
&& ad->disp == ad->disp_term);
}
/* Make equiv substitution in address AD. Return true if a substitution
was made. */
static bool
equiv_address_substitution (struct address_info *ad)
{
rtx base_reg, new_base_reg, index_reg, new_index_reg, *base_term, *index_term;
HOST_WIDE_INT disp, scale;
bool change_p;
base_term = strip_subreg (ad->base_term);
if (base_term == NULL)
base_reg = new_base_reg = NULL_RTX;
else
{
base_reg = *base_term;
new_base_reg = get_equiv_with_elimination (base_reg, curr_insn);
}
index_term = strip_subreg (ad->index_term);
if (index_term == NULL)
index_reg = new_index_reg = NULL_RTX;
else
{
index_reg = *index_term;
new_index_reg = get_equiv_with_elimination (index_reg, curr_insn);
}
if (base_reg == new_base_reg && index_reg == new_index_reg)
return false;
disp = 0;
change_p = false;
if (lra_dump_file != NULL)
{
fprintf (lra_dump_file, "Changing address in insn %d ",
INSN_UID (curr_insn));
dump_value_slim (lra_dump_file, *ad->outer, 1);
}
if (base_reg != new_base_reg)
{
if (REG_P (new_base_reg))
{
*base_term = new_base_reg;
change_p = true;
}
else if (GET_CODE (new_base_reg) == PLUS
&& REG_P (XEXP (new_base_reg, 0))
&& CONST_INT_P (XEXP (new_base_reg, 1))
&& can_add_disp_p (ad))
{
disp += INTVAL (XEXP (new_base_reg, 1));
*base_term = XEXP (new_base_reg, 0);
change_p = true;
}
if (ad->base_term2 != NULL)
*ad->base_term2 = *ad->base_term;
}
if (index_reg != new_index_reg)
{
if (REG_P (new_index_reg))
{
*index_term = new_index_reg;
change_p = true;
}
else if (GET_CODE (new_index_reg) == PLUS
&& REG_P (XEXP (new_index_reg, 0))
&& CONST_INT_P (XEXP (new_index_reg, 1))
&& can_add_disp_p (ad)
&& (scale = get_index_scale (ad)))
{
disp += INTVAL (XEXP (new_index_reg, 1)) * scale;
*index_term = XEXP (new_index_reg, 0);
change_p = true;
}
}
if (disp != 0)
{
if (ad->disp != NULL)
*ad->disp = plus_constant (GET_MODE (*ad->inner), *ad->disp, disp);
else
{
*ad->inner = plus_constant (GET_MODE (*ad->inner), *ad->inner, disp);
update_address (ad);
}
change_p = true;
}
if (lra_dump_file != NULL)
{
if (! change_p)
fprintf (lra_dump_file, " -- no change\n");
else
{
fprintf (lra_dump_file, " on equiv ");
dump_value_slim (lra_dump_file, *ad->outer, 1);
fprintf (lra_dump_file, "\n");
}
}
return change_p;
}
/* Major function to make reloads for an address in operand NOP or
check its correctness (If CHECK_ONLY_P is true). The supported
cases are:
1) an address that existed before LRA started, at which point it
must have been valid. These addresses are subject to elimination
and may have become invalid due to the elimination offset being out
of range.
2) an address created by forcing a constant to memory
(force_const_to_mem). The initial form of these addresses might
not be valid, and it is this function's job to make them valid.
3) a frame address formed from a register and a (possibly zero)
constant offset. As above, these addresses might not be valid and
this function must make them so.
Add reloads to the lists *BEFORE and *AFTER. We might need to add
reloads to *AFTER because of inc/dec, {pre, post} modify in the
address. Return true for any RTL change.
The function is a helper function which does not produce all
transformations (when CHECK_ONLY_P is false) which can be
necessary. It does just basic steps. To do all necessary
transformations use function process_address. */
static bool
process_address_1 (int nop, bool check_only_p,
rtx_insn **before, rtx_insn **after)
{
struct address_info ad;
rtx new_reg;
rtx op = *curr_id->operand_loc[nop];
const char *constraint = curr_static_id->operand[nop].constraint;
enum constraint_num cn = lookup_constraint (constraint);
bool change_p = false;
if (insn_extra_address_constraint (cn))
decompose_lea_address (&ad, curr_id->operand_loc[nop]);
else if (MEM_P (op))
decompose_mem_address (&ad, op);
else if (GET_CODE (op) == SUBREG
&& MEM_P (SUBREG_REG (op)))
decompose_mem_address (&ad, SUBREG_REG (op));
else
return false;
/* If INDEX_REG_CLASS is assigned to base_term already and isn't to
index_term, swap them so to avoid assigning INDEX_REG_CLASS to both
when INDEX_REG_CLASS is a single register class. */
if (ad.base_term != NULL
&& ad.index_term != NULL
&& ira_class_hard_regs_num[INDEX_REG_CLASS] == 1
&& REG_P (*ad.base_term)
&& REG_P (*ad.index_term)
&& in_class_p (*ad.base_term, INDEX_REG_CLASS, NULL)
&& ! in_class_p (*ad.index_term, INDEX_REG_CLASS, NULL))
{
std::swap (ad.base, ad.index);
std::swap (ad.base_term, ad.index_term);
}
if (! check_only_p)
change_p = equiv_address_substitution (&ad);
if (ad.base_term != NULL
&& (process_addr_reg
(ad.base_term, check_only_p, before,
(ad.autoinc_p
&& !(REG_P (*ad.base_term)
&& find_regno_note (curr_insn, REG_DEAD,
REGNO (*ad.base_term)) != NULL_RTX)
? after : NULL),
base_reg_class (ad.mode, ad.as, ad.base_outer_code,
get_index_code (&ad)))))
{
change_p = true;
if (ad.base_term2 != NULL)
*ad.base_term2 = *ad.base_term;
}
if (ad.index_term != NULL
&& process_addr_reg (ad.index_term, check_only_p,
before, NULL, INDEX_REG_CLASS))
change_p = true;
/* Target hooks sometimes don't treat extra-constraint addresses as
legitimate address_operands, so handle them specially. */
if (insn_extra_address_constraint (cn)
&& satisfies_address_constraint_p (&ad, cn))
return change_p;
if (check_only_p)
return change_p;
/* There are three cases where the shape of *AD.INNER may now be invalid:
1) the original address was valid, but either elimination or
equiv_address_substitution was applied and that made
the address invalid.
2) the address is an invalid symbolic address created by
force_const_to_mem.
3) the address is a frame address with an invalid offset.
4) the address is a frame address with an invalid base.
All these cases involve a non-autoinc address, so there is no
point revalidating other types. */
if (ad.autoinc_p || valid_address_p (&ad))
return change_p;
/* Any index existed before LRA started, so we can assume that the
presence and shape of the index is valid. */
push_to_sequence (*before);
lra_assert (ad.disp == ad.disp_term);
if (ad.base == NULL)
{
if (ad.index == NULL)
{
int code = -1;
enum reg_class cl = base_reg_class (ad.mode, ad.as,
SCRATCH, SCRATCH);
rtx addr = *ad.inner;
new_reg = lra_create_new_reg (Pmode, NULL_RTX, cl, "addr");
#ifdef HAVE_lo_sum
{
rtx_insn *insn;
rtx_insn *last = get_last_insn ();
/* addr => lo_sum (new_base, addr), case (2) above. */
insn = emit_insn (gen_rtx_SET
(VOIDmode, new_reg,
gen_rtx_HIGH (Pmode, copy_rtx (addr))));
code = recog_memoized (insn);
if (code >= 0)
{
*ad.inner = gen_rtx_LO_SUM (Pmode, new_reg, addr);
if (! valid_address_p (ad.mode, *ad.outer, ad.as))
{
/* Try to put lo_sum into register. */
insn = emit_insn (gen_rtx_SET
(VOIDmode, new_reg,
gen_rtx_LO_SUM (Pmode, new_reg, addr)));
code = recog_memoized (insn);
if (code >= 0)
{
*ad.inner = new_reg;
if (! valid_address_p (ad.mode, *ad.outer, ad.as))
{
*ad.inner = addr;
code = -1;
}
}
}
}
if (code < 0)
delete_insns_since (last);
}
#endif
if (code < 0)
{
/* addr => new_base, case (2) above. */
lra_emit_move (new_reg, addr);
*ad.inner = new_reg;
}
}
else
{
/* index * scale + disp => new base + index * scale,
case (1) above. */
enum reg_class cl = base_reg_class (ad.mode, ad.as, PLUS,
GET_CODE (*ad.index));
lra_assert (INDEX_REG_CLASS != NO_REGS);
new_reg = lra_create_new_reg (Pmode, NULL_RTX, cl, "disp");
lra_emit_move (new_reg, *ad.disp);
*ad.inner = simplify_gen_binary (PLUS, GET_MODE (new_reg),
new_reg, *ad.index);
}
}
else if (ad.index == NULL)
{
int regno;
enum reg_class cl;
rtx set;
rtx_insn *insns, *last_insn;
/* Try to reload base into register only if the base is invalid
for the address but with valid offset, case (4) above. */
start_sequence ();
new_reg = base_to_reg (&ad);
/* base + disp => new base, cases (1) and (3) above. */
/* Another option would be to reload the displacement into an
index register. However, postreload has code to optimize
address reloads that have the same base and different
displacements, so reloading into an index register would
not necessarily be a win. */
if (new_reg == NULL_RTX)
new_reg = base_plus_disp_to_reg (&ad);
insns = get_insns ();
last_insn = get_last_insn ();
/* If we generated at least two insns, try last insn source as
an address. If we succeed, we generate one less insn. */
if (last_insn != insns && (set = single_set (last_insn)) != NULL_RTX
&& GET_CODE (SET_SRC (set)) == PLUS
&& REG_P (XEXP (SET_SRC (set), 0))
&& CONSTANT_P (XEXP (SET_SRC (set), 1)))
{
*ad.inner = SET_SRC (set);
if (valid_address_p (ad.mode, *ad.outer, ad.as))
{
*ad.base_term = XEXP (SET_SRC (set), 0);
*ad.disp_term = XEXP (SET_SRC (set), 1);
cl = base_reg_class (ad.mode, ad.as, ad.base_outer_code,
get_index_code (&ad));
regno = REGNO (*ad.base_term);
if (regno >= FIRST_PSEUDO_REGISTER
&& cl != lra_get_allocno_class (regno))
lra_change_class (regno, cl, " Change to", true);
new_reg = SET_SRC (set);
delete_insns_since (PREV_INSN (last_insn));
}
}
/* Try if target can split displacement into legitimite new disp
and offset. If it's the case, we replace the last insn with
insns for base + offset => new_reg and set new_reg + new disp
to *ad.inner. */
last_insn = get_last_insn ();
if ((set = single_set (last_insn)) != NULL_RTX
&& GET_CODE (SET_SRC (set)) == PLUS
&& REG_P (XEXP (SET_SRC (set), 0))
&& REGNO (XEXP (SET_SRC (set), 0)) < FIRST_PSEUDO_REGISTER
&& CONST_INT_P (XEXP (SET_SRC (set), 1)))
{
rtx addend, disp = XEXP (SET_SRC (set), 1);
if (targetm.legitimize_address_displacement (&disp, &addend,
ad.mode))
{
rtx_insn *new_insns;
start_sequence ();
lra_emit_add (new_reg, XEXP (SET_SRC (set), 0), addend);
new_insns = get_insns ();
end_sequence ();
new_reg = gen_rtx_PLUS (Pmode, new_reg, disp);
delete_insns_since (PREV_INSN (last_insn));
add_insn (new_insns);
insns = get_insns ();
}
}