/* RTL-level loop invariant motion.
- Copyright (C) 2004, 2005, 2006 Free Software Foundation, Inc.
+ Copyright (C) 2004-2015 Free Software Foundation, Inc.
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 2, or (at your option) any
+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
for more details.
You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING. If not, write to the Free
-Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
-02110-1301, USA. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
/* This implements the loop invariant motion pass. It is very simple
- (no calls, libcalls, etc.). This should be sufficient to cleanup things
- like address arithmetics -- other more complicated invariants should be
- eliminated on tree level either in tree-ssa-loop-im.c or in tree-ssa-pre.c.
+ (no calls, no loads/stores, etc.). This should be sufficient to cleanup
+ things like address arithmetics -- other more complicated invariants should
+ be eliminated on GIMPLE either in tree-ssa-loop-im.c or in tree-ssa-pre.c.
We proceed loop by loop -- it is simpler than trying to handle things
globally and should not lose much. First we inspect all sets inside loop
#include "system.h"
#include "coretypes.h"
#include "tm.h"
+#include "hard-reg-set.h"
#include "rtl.h"
#include "tm_p.h"
-#include "hard-reg-set.h"
#include "obstack.h"
+#include "predict.h"
+#include "vec.h"
+#include "hashtab.h"
+#include "hash-set.h"
+#include "machmode.h"
+#include "input.h"
+#include "function.h"
+#include "dominance.h"
+#include "cfg.h"
+#include "cfgrtl.h"
#include "basic-block.h"
#include "cfgloop.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 "insn-config.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 "recog.h"
-#include "output.h"
-#include "function.h"
-#include "flags.h"
+#include "target.h"
#include "df.h"
-#include "hashtab.h"
+#include "hash-table.h"
#include "except.h"
+#include "params.h"
+#include "regs.h"
+#include "ira.h"
+#include "dumpfile.h"
/* The data stored for the loop. */
{
struct loop *outermost_exit; /* The outermost exit of the loop. */
bool has_call; /* True if the loop contains a call. */
+ /* Maximal register pressure inside loop for given register class
+ (defined only for the pressure classes). */
+ int max_reg_pressure[N_REG_CLASSES];
+ /* Loop regs referenced and live pseudo-registers. */
+ bitmap_head regs_ref;
+ bitmap_head regs_live;
};
#define LOOP_DATA(LOOP) ((struct loop_data *) (LOOP)->aux)
struct use
{
rtx *pos; /* Position of the use. */
- rtx insn; /* The insn in that the use occurs. */
-
+ rtx_insn *insn; /* The insn in that the use occurs. */
+ unsigned addr_use_p; /* Whether the use occurs in an address. */
struct use *next; /* Next use in the list. */
};
struct use *uses; /* The list of uses that are uniquely reached
by it. */
unsigned n_uses; /* Number of such uses. */
+ unsigned n_addr_uses; /* Number of uses in addresses. */
unsigned invno; /* The corresponding invariant. */
};
/* The number of the invariant with the same value. */
unsigned eqto;
+ /* The number of invariants which eqto this. */
+ unsigned eqno;
+
/* If we moved the invariant out of the loop, the register that contains its
value. */
rtx reg;
+ /* If we moved the invariant out of the loop, the original regno
+ that contained its value. */
+ int orig_regno;
+
/* The definition of the invariant. */
struct def *def;
/* The insn in that it is defined. */
- rtx insn;
+ rtx_insn *insn;
/* Whether it is always executed. */
bool always_executed;
/* Whether to move the invariant. */
bool move;
+ /* Whether the invariant is cheap when used as an address. */
+ bool cheap_address;
+
/* Cost of the invariant. */
unsigned cost;
unsigned stamp;
};
+/* Currently processed loop. */
+static struct loop *curr_loop;
+
+/* Table of invariants indexed by the df_ref uid field. */
+
+static unsigned int invariant_table_size = 0;
+static struct invariant ** invariant_table;
+
/* Entry for hash table of invariant expressions. */
struct invariant_expr_entry
rtx expr;
/* Its mode. */
- enum machine_mode mode;
+ machine_mode mode;
/* Its hash. */
hashval_t hash;
typedef struct invariant *invariant_p;
-DEF_VEC_P(invariant_p);
-DEF_VEC_ALLOC_P(invariant_p, heap);
/* The invariants. */
-static VEC(invariant_p,heap) *invariants;
+static vec<invariant_p> invariants;
-/* The dataflow object. */
+/* Check the size of the invariant table and realloc if necessary. */
-static struct df *df = NULL;
+static void
+check_invariant_table_size (void)
+{
+ if (invariant_table_size < DF_DEFS_TABLE_SIZE ())
+ {
+ unsigned int new_size = DF_DEFS_TABLE_SIZE () + (DF_DEFS_TABLE_SIZE () / 4);
+ invariant_table = XRESIZEVEC (struct invariant *, invariant_table, new_size);
+ memset (&invariant_table[invariant_table_size], 0,
+ (new_size - invariant_table_size) * sizeof (struct invariant *));
+ invariant_table_size = new_size;
+ }
+}
/* Test for possibility of invariantness of X. */
switch (code)
{
- case CONST_INT:
- case CONST_DOUBLE:
+ CASE_CONST_ANY:
case SYMBOL_REF:
case CONST:
case LABEL_REF:
/* Just handle the most trivial case where we load from an unchanging
location (most importantly, pic tables). */
- if (MEM_READONLY_P (x))
+ if (MEM_READONLY_P (x) && !MEM_VOLATILE_P (x))
break;
return false;
invariant. */
static struct invariant *
-invariant_for_use (struct df_ref *use)
+invariant_for_use (df_ref use)
{
struct df_link *defs;
- struct df_ref *def;
- basic_block bb = BLOCK_FOR_INSN (use->insn), def_bb;
+ df_ref def;
+ basic_block bb = DF_REF_BB (use), def_bb;
- if (use->flags & DF_REF_READ_WRITE)
+ if (DF_REF_FLAGS (use) & DF_REF_READ_WRITE)
return NULL;
defs = DF_REF_CHAIN (use);
if (!defs || defs->next)
return NULL;
def = defs->ref;
- if (!DF_REF_DATA (def))
+ check_invariant_table_size ();
+ if (!invariant_table[DF_REF_ID (def)])
return NULL;
def_bb = DF_REF_BB (def);
if (!dominated_by_p (CDI_DOMINATORS, bb, def_bb))
return NULL;
- return DF_REF_DATA (def);
+ return invariant_table[DF_REF_ID (def)];
}
/* Computes hash value for invariant expression X in INSN. */
static hashval_t
-hash_invariant_expr_1 (rtx insn, rtx x)
+hash_invariant_expr_1 (rtx_insn *insn, rtx x)
{
enum rtx_code code = GET_CODE (x);
int i, j;
const char *fmt;
hashval_t val = code;
int do_not_record_p;
- struct df_ref *use;
+ df_ref use;
struct invariant *inv;
switch (code)
{
- case CONST_INT:
- case CONST_DOUBLE:
+ CASE_CONST_ANY:
case SYMBOL_REF:
case CONST:
case LABEL_REF:
return hash_rtx (x, GET_MODE (x), &do_not_record_p, NULL, false);
case REG:
- use = df_find_use (df, insn, x);
+ use = df_find_use (insn, x);
if (!use)
return hash_rtx (x, GET_MODE (x), &do_not_record_p, NULL, false);
inv = invariant_for_use (use);
and INSN2 have always the same value. */
static bool
-invariant_expr_equal_p (rtx insn1, rtx e1, rtx insn2, rtx e2)
+invariant_expr_equal_p (rtx_insn *insn1, rtx e1, rtx_insn *insn2, rtx e2)
{
enum rtx_code code = GET_CODE (e1);
int i, j;
const char *fmt;
- struct df_ref *use1, *use2;
+ df_ref use1, use2;
struct invariant *inv1 = NULL, *inv2 = NULL;
rtx sub1, sub2;
switch (code)
{
- case CONST_INT:
- case CONST_DOUBLE:
+ CASE_CONST_ANY:
case SYMBOL_REF:
case CONST:
case LABEL_REF:
return rtx_equal_p (e1, e2);
case REG:
- use1 = df_find_use (df, insn1, e1);
- use2 = df_find_use (df, insn2, e2);
+ use1 = df_find_use (insn1, e1);
+ use2 = df_find_use (insn2, e2);
if (use1)
inv1 = invariant_for_use (use1);
if (use2)
return true;
}
-/* Returns hash value for invariant expression entry E. */
-
-static hashval_t
-hash_invariant_expr (const void *e)
+struct invariant_expr_hasher : typed_free_remove <invariant_expr_entry>
{
- const struct invariant_expr_entry *entry = e;
+ typedef invariant_expr_entry *value_type;
+ typedef invariant_expr_entry *compare_type;
+ static inline hashval_t hash (const invariant_expr_entry *);
+ static inline bool equal (const invariant_expr_entry *,
+ const invariant_expr_entry *);
+};
+
+/* Returns hash value for invariant expression entry ENTRY. */
+inline hashval_t
+invariant_expr_hasher::hash (const invariant_expr_entry *entry)
+{
return entry->hash;
}
-/* Compares invariant expression entries E1 and E2. */
+/* Compares invariant expression entries ENTRY1 and ENTRY2. */
-static int
-eq_invariant_expr (const void *e1, const void *e2)
+inline bool
+invariant_expr_hasher::equal (const invariant_expr_entry *entry1,
+ const invariant_expr_entry *entry2)
{
- const struct invariant_expr_entry *entry1 = e1;
- const struct invariant_expr_entry *entry2 = e2;
-
if (entry1->mode != entry2->mode)
return 0;
entry2->inv->insn, entry2->expr);
}
+typedef hash_table<invariant_expr_hasher> invariant_htab_type;
+
/* Checks whether invariant with value EXPR in machine mode MODE is
recorded in EQ. If this is the case, return the invariant. Otherwise
insert INV to the table for this expression and return INV. */
static struct invariant *
-find_or_insert_inv (htab_t eq, rtx expr, enum machine_mode mode,
+find_or_insert_inv (invariant_htab_type *eq, rtx expr, machine_mode mode,
struct invariant *inv)
{
hashval_t hash = hash_invariant_expr_1 (inv->insn, expr);
struct invariant_expr_entry *entry;
struct invariant_expr_entry pentry;
- PTR *slot;
+ invariant_expr_entry **slot;
pentry.expr = expr;
pentry.inv = inv;
pentry.mode = mode;
- slot = htab_find_slot_with_hash (eq, &pentry, hash, INSERT);
+ slot = eq->find_slot_with_hash (&pentry, hash, INSERT);
entry = *slot;
if (entry)
hash table of the invariants. */
static void
-find_identical_invariants (htab_t eq, struct invariant *inv)
+find_identical_invariants (invariant_htab_type *eq, struct invariant *inv)
{
unsigned depno;
bitmap_iterator bi;
struct invariant *dep;
rtx expr, set;
- enum machine_mode mode;
+ machine_mode mode;
+ struct invariant *tmp;
if (inv->eqto != ~0u)
return;
EXECUTE_IF_SET_IN_BITMAP (inv->depends_on, 0, depno, bi)
{
- dep = VEC_index (invariant_p, invariants, depno);
+ dep = invariants[depno];
find_identical_invariants (eq, dep);
}
mode = GET_MODE (expr);
if (mode == VOIDmode)
mode = GET_MODE (SET_DEST (set));
- inv->eqto = find_or_insert_inv (eq, expr, mode, inv)->invno;
+
+ tmp = find_or_insert_inv (eq, expr, mode, inv);
+ inv->eqto = tmp->invno;
+
+ if (tmp->invno != inv->invno && inv->always_executed)
+ tmp->eqno++;
if (dump_file && inv->eqto != inv->invno)
fprintf (dump_file,
{
unsigned i;
struct invariant *inv;
- htab_t eq = htab_create (VEC_length (invariant_p, invariants),
- hash_invariant_expr, eq_invariant_expr, free);
-
- for (i = 0; VEC_iterate (invariant_p, invariants, i, inv); i++)
- find_identical_invariants (eq, inv);
+ invariant_htab_type eq (invariants.length ());
- htab_delete (eq);
+ FOR_EACH_VEC_ELT (invariants, i, inv)
+ find_identical_invariants (&eq, inv);
}
/* Determines the basic blocks inside LOOP that are always executed and
edge e;
struct loop *outermost_exit = loop, *aexit;
bool has_call = false;
- rtx insn;
+ rtx_insn *insn;
for (i = 0; i < loop->num_nodes; i++)
{
FOR_BB_INSNS (body[i], insn)
{
if (CALL_P (insn)
- && !CONST_OR_PURE_CALL_P (insn))
+ && (RTL_LOOPING_CONST_OR_PURE_CALL_P (insn)
+ || !RTL_CONST_OR_PURE_CALL_P (insn)))
{
has_call = true;
bitmap_set_bit (may_exit, i);
}
}
- loop->aux = xcalloc (1, sizeof (struct loop_data));
+ if (loop->aux == NULL)
+ {
+ loop->aux = xcalloc (1, sizeof (struct loop_data));
+ bitmap_initialize (&LOOP_DATA (loop)->regs_ref, ®_obstack);
+ bitmap_initialize (&LOOP_DATA (loop)->regs_live, ®_obstack);
+ }
LOOP_DATA (loop)->outermost_exit = outermost_exit;
LOOP_DATA (loop)->has_call = has_call;
}
BODY. */
static void
-find_defs (struct loop *loop, basic_block *body)
+find_defs (struct loop *loop)
{
- unsigned i;
- bitmap blocks = BITMAP_ALLOC (NULL);
+ if (dump_file)
+ {
+ fprintf (dump_file,
+ "*****starting processing of loop %d ******\n",
+ loop->num);
+ }
- for (i = 0; i < loop->num_nodes; i++)
- bitmap_set_bit (blocks, body[i]->index);
+ df_remove_problem (df_chain);
+ df_process_deferred_rescans ();
+ df_chain_add_problem (DF_UD_CHAIN);
+ df_set_flags (DF_RD_PRUNE_DEAD_DEFS);
+ df_analyze_loop (loop);
+ check_invariant_table_size ();
- df_set_blocks (df, blocks);
- df_analyze (df);
- BITMAP_FREE (blocks);
+ if (dump_file)
+ {
+ df_dump_region (dump_file);
+ fprintf (dump_file,
+ "*****ending processing of loop %d ******\n",
+ loop->num);
+ }
}
/* Creates a new invariant for definition DEF in INSN, depending on invariants
is returned. */
static struct invariant *
-create_new_invariant (struct def *def, rtx insn, bitmap depends_on,
+create_new_invariant (struct def *def, rtx_insn *insn, bitmap depends_on,
bool always_executed)
{
struct invariant *inv = XNEW (struct invariant);
rtx set = single_set (insn);
+ bool speed = optimize_bb_for_speed_p (BLOCK_FOR_INSN (insn));
inv->def = def;
inv->always_executed = always_executed;
/* If the set is simple, usually by moving it we move the whole store out of
the loop. Otherwise we save only cost of the computation. */
if (def)
- inv->cost = rtx_cost (set, SET);
+ {
+ inv->cost = set_rtx_cost (set, speed);
+ /* ??? Try to determine cheapness of address computation. Unfortunately
+ the address cost is only a relative measure, we can't really compare
+ it with any absolute number, but only with other address costs.
+ But here we don't have any other addresses, so compare with a magic
+ number anyway. It has to be large enough to not regress PR33928
+ (by avoiding to move reg+8,reg+16,reg+24 invariants), but small
+ enough to not regress 410.bwaves either (by still moving reg+reg
+ invariants).
+ See http://gcc.gnu.org/ml/gcc-patches/2009-10/msg01210.html . */
+ if (SCALAR_INT_MODE_P (GET_MODE (SET_DEST (set))))
+ inv->cheap_address = address_cost (SET_SRC (set), word_mode,
+ ADDR_SPACE_GENERIC, speed) < 3;
+ else
+ inv->cheap_address = false;
+ }
else
- inv->cost = rtx_cost (SET_SRC (set), SET);
+ {
+ inv->cost = set_src_cost (SET_SRC (set), speed);
+ inv->cheap_address = false;
+ }
inv->move = false;
inv->reg = NULL_RTX;
+ inv->orig_regno = -1;
inv->stamp = 0;
inv->insn = insn;
- inv->invno = VEC_length (invariant_p, invariants);
+ inv->invno = invariants.length ();
inv->eqto = ~0u;
+
+ /* Itself. */
+ inv->eqno = 1;
+
if (def)
def->invno = inv->invno;
- VEC_safe_push (invariant_p, heap, invariants, inv);
+ invariants.safe_push (inv);
if (dump_file)
{
/* Record USE at DEF. */
static void
-record_use (struct def *def, rtx *use, rtx insn)
+record_use (struct def *def, df_ref use)
{
struct use *u = XNEW (struct use);
- if (GET_CODE (*use) == SUBREG)
- use = &SUBREG_REG (*use);
- gcc_assert (REG_P (*use));
-
- u->pos = use;
- u->insn = insn;
+ u->pos = DF_REF_REAL_LOC (use);
+ u->insn = DF_REF_INSN (use);
+ u->addr_use_p = (DF_REF_TYPE (use) == DF_REF_REG_MEM_LOAD
+ || DF_REF_TYPE (use) == DF_REF_REG_MEM_STORE);
u->next = def->uses;
def->uses = u;
def->n_uses++;
+ if (u->addr_use_p)
+ def->n_addr_uses++;
}
-/* Finds the invariants INSN depends on and store them to the DEPENDS_ON
- bitmap. Returns true if all dependencies of INSN are known to be
+/* Finds the invariants USE depends on and store them to the DEPENDS_ON
+ bitmap. Returns true if all dependencies of USE are known to be
loop invariants, false otherwise. */
static bool
-check_dependencies (rtx insn, bitmap depends_on)
+check_dependency (basic_block bb, df_ref use, bitmap depends_on)
{
+ df_ref def;
+ basic_block def_bb;
struct df_link *defs;
- struct df_ref *use, *def;
- basic_block bb = BLOCK_FOR_INSN (insn), def_bb;
struct def *def_data;
struct invariant *inv;
- for (use = DF_INSN_GET (df, insn)->uses; use; use = use->next_ref)
+ if (DF_REF_FLAGS (use) & DF_REF_READ_WRITE)
+ return false;
+
+ defs = DF_REF_CHAIN (use);
+ if (!defs)
{
- if (use->flags & DF_REF_READ_WRITE)
+ unsigned int regno = DF_REF_REGNO (use);
+
+ /* If this is the use of an uninitialized argument register that is
+ likely to be spilled, do not move it lest this might extend its
+ lifetime and cause reload to die. This can occur for a call to
+ a function taking complex number arguments and moving the insns
+ preparing the arguments without moving the call itself wouldn't
+ gain much in practice. */
+ if ((DF_REF_FLAGS (use) & DF_HARD_REG_LIVE)
+ && FUNCTION_ARG_REGNO_P (regno)
+ && targetm.class_likely_spilled_p (REGNO_REG_CLASS (regno)))
return false;
- defs = DF_REF_CHAIN (use);
- if (!defs)
- continue;
+ return true;
+ }
- if (defs->next)
- return false;
+ if (defs->next)
+ return false;
- def = defs->ref;
- inv = DF_REF_DATA (def);
- if (!inv)
- return false;
+ def = defs->ref;
+ check_invariant_table_size ();
+ inv = invariant_table[DF_REF_ID (def)];
+ if (!inv)
+ return false;
- def_data = inv->def;
- gcc_assert (def_data != NULL);
+ def_data = inv->def;
+ gcc_assert (def_data != NULL);
- def_bb = DF_REF_BB (def);
- /* Note that in case bb == def_bb, we know that the definition dominates
- insn, because def has DF_REF_DATA defined and we process the insns
- in the basic block bb sequentially. */
- if (!dominated_by_p (CDI_DOMINATORS, bb, def_bb))
- return false;
+ def_bb = DF_REF_BB (def);
+ /* Note that in case bb == def_bb, we know that the definition
+ dominates insn, because def has invariant_table[DF_REF_ID(def)]
+ defined and we process the insns in the basic block bb
+ sequentially. */
+ if (!dominated_by_p (CDI_DOMINATORS, bb, def_bb))
+ return false;
- bitmap_set_bit (depends_on, def_data->invno);
- }
+ bitmap_set_bit (depends_on, def_data->invno);
+ return true;
+}
+
+
+/* Finds the invariants INSN depends on and store them to the DEPENDS_ON
+ bitmap. Returns true if all dependencies of INSN are known to be
+ loop invariants, false otherwise. */
+
+static bool
+check_dependencies (rtx_insn *insn, bitmap depends_on)
+{
+ struct df_insn_info *insn_info = DF_INSN_INFO_GET (insn);
+ df_ref use;
+ basic_block bb = BLOCK_FOR_INSN (insn);
+
+ FOR_EACH_INSN_INFO_USE (use, insn_info)
+ if (!check_dependency (bb, use, depends_on))
+ return false;
+ FOR_EACH_INSN_INFO_EQ_USE (use, insn_info)
+ if (!check_dependency (bb, use, depends_on))
+ return false;
+
+ return true;
+}
+
+/* Pre-check candidate DEST to skip the one which can not make a valid insn
+ during move_invariant_reg. SIMPLE is to skip HARD_REGISTER. */
+static bool
+pre_check_invariant_p (bool simple, rtx dest)
+{
+ if (simple && REG_P (dest) && DF_REG_DEF_COUNT (REGNO (dest)) > 1)
+ {
+ df_ref use;
+ rtx ref;
+ unsigned int i = REGNO (dest);
+ struct df_insn_info *insn_info;
+ df_ref def_rec;
+ for (use = DF_REG_USE_CHAIN (i); use; use = DF_REF_NEXT_REG (use))
+ {
+ ref = DF_REF_INSN (use);
+ insn_info = DF_INSN_INFO_GET (ref);
+
+ FOR_EACH_INSN_INFO_DEF (def_rec, insn_info)
+ if (DF_REF_REGNO (def_rec) == i)
+ {
+ /* Multi definitions at this stage, most likely are due to
+ instruction constraints, which requires both read and write
+ on the same register. Since move_invariant_reg is not
+ powerful enough to handle such cases, just ignore the INV
+ and leave the chance to others. */
+ return false;
+ }
+ }
+ }
return true;
}
unless the program ends due to a function call. */
static void
-find_invariant_insn (rtx insn, bool always_reached, bool always_executed)
+find_invariant_insn (rtx_insn *insn, bool always_reached, bool always_executed)
{
- struct df_ref *ref;
+ df_ref ref;
struct def *def;
bitmap depends_on;
rtx set, dest;
bool simple = true;
struct invariant *inv;
- /* Until we get rid of LIBCALLS. */
- if (find_reg_note (insn, REG_RETVAL, NULL_RTX)
- || find_reg_note (insn, REG_LIBCALL, NULL_RTX)
- || find_reg_note (insn, REG_NO_CONFLICT, NULL_RTX))
- return;
-
-#ifdef HAVE_cc0
/* We can't move a CC0 setter without the user. */
- if (sets_cc0_p (insn))
+ if (HAVE_cc0 && sets_cc0_p (insn))
return;
-#endif
set = single_set (insn);
if (!set)
|| HARD_REGISTER_P (dest))
simple = false;
- if (!may_assign_reg_p (SET_DEST (set))
+ if (!may_assign_reg_p (dest)
+ || !pre_check_invariant_p (simple, dest)
|| !check_maybe_invariant (SET_SRC (set)))
return;
return;
/* We cannot make trapping insn executed, unless it was executed before. */
- if (may_trap_after_code_motion_p (PATTERN (insn)) && !always_reached)
+ if (may_trap_or_fault_p (PATTERN (insn)) && !always_reached)
return;
depends_on = BITMAP_ALLOC (NULL);
if (simple)
{
- ref = df_find_def (df, insn, dest);
- DF_REF_DATA (ref) = inv;
+ ref = df_find_def (insn, dest);
+ check_invariant_table_size ();
+ invariant_table[DF_REF_ID (ref)] = inv;
}
}
/* Record registers used in INSN that have a unique invariant definition. */
static void
-record_uses (rtx insn)
+record_uses (rtx_insn *insn)
{
- struct df_ref *use;
+ struct df_insn_info *insn_info = DF_INSN_INFO_GET (insn);
+ df_ref use;
struct invariant *inv;
- for (use = DF_INSN_GET (df, insn)->uses; use; use = use->next_ref)
+ FOR_EACH_INSN_INFO_USE (use, insn_info)
+ {
+ inv = invariant_for_use (use);
+ if (inv)
+ record_use (inv->def, use);
+ }
+ FOR_EACH_INSN_INFO_EQ_USE (use, insn_info)
{
inv = invariant_for_use (use);
if (inv)
- record_use (inv->def, DF_REF_LOC (use), DF_REF_INSN (use));
+ record_use (inv->def, use);
}
}
unless the program ends due to a function call. */
static void
-find_invariants_insn (rtx insn, bool always_reached, bool always_executed)
+find_invariants_insn (rtx_insn *insn, bool always_reached, bool always_executed)
{
find_invariant_insn (insn, always_reached, always_executed);
record_uses (insn);
static void
find_invariants_bb (basic_block bb, bool always_reached, bool always_executed)
{
- rtx insn;
+ rtx_insn *insn;
FOR_BB_INSNS (bb, insn)
{
- if (!INSN_P (insn))
+ if (!NONDEBUG_INSN_P (insn))
continue;
find_invariants_insn (insn, always_reached, always_executed);
if (always_reached
&& CALL_P (insn)
- && !CONST_OR_PURE_CALL_P (insn))
+ && (RTL_LOOPING_CONST_OR_PURE_CALL_P (insn)
+ || ! RTL_CONST_OR_PURE_CALL_P (insn)))
always_reached = false;
}
}
compute_always_reached (loop, body, may_exit, always_reached);
compute_always_reached (loop, body, has_exit, always_executed);
- find_defs (loop, body);
+ find_defs (loop);
find_invariants_body (loop, body, always_reached, always_executed);
merge_identical_invariants ();
}
}
+/* Return pressure class and number of hard registers (through *NREGS)
+ for destination of INSN. */
+static enum reg_class
+get_pressure_class_and_nregs (rtx_insn *insn, int *nregs)
+{
+ rtx reg;
+ enum reg_class pressure_class;
+ rtx set = single_set (insn);
+
+ /* Considered invariant insns have only one set. */
+ gcc_assert (set != NULL_RTX);
+ reg = SET_DEST (set);
+ if (GET_CODE (reg) == SUBREG)
+ reg = SUBREG_REG (reg);
+ if (MEM_P (reg))
+ {
+ *nregs = 0;
+ pressure_class = NO_REGS;
+ }
+ else
+ {
+ if (! REG_P (reg))
+ reg = NULL_RTX;
+ if (reg == NULL_RTX)
+ pressure_class = GENERAL_REGS;
+ else
+ {
+ pressure_class = reg_allocno_class (REGNO (reg));
+ pressure_class = ira_pressure_class_translate[pressure_class];
+ }
+ *nregs
+ = ira_reg_class_max_nregs[pressure_class][GET_MODE (SET_SRC (set))];
+ }
+ return pressure_class;
+}
+
/* Calculates cost and number of registers needed for moving invariant INV
- out of the loop and stores them to *COST and *REGS_NEEDED. */
+ out of the loop and stores them to *COST and *REGS_NEEDED. *CL will be
+ the REG_CLASS of INV. Return
+ -1: if INV is invalid.
+ 0: if INV and its depends_on have same reg_class
+ 1: if INV and its depends_on have different reg_classes. */
-static void
-get_inv_cost (struct invariant *inv, int *comp_cost, unsigned *regs_needed)
+static int
+get_inv_cost (struct invariant *inv, int *comp_cost, unsigned *regs_needed,
+ enum reg_class *cl)
{
- int acomp_cost;
- unsigned aregs_needed;
+ int i, acomp_cost;
+ unsigned aregs_needed[N_REG_CLASSES];
unsigned depno;
struct invariant *dep;
bitmap_iterator bi;
+ int ret = 1;
/* Find the representative of the class of the equivalent invariants. */
- inv = VEC_index (invariant_p, invariants, inv->eqto);
+ inv = invariants[inv->eqto];
*comp_cost = 0;
- *regs_needed = 0;
+ if (! flag_ira_loop_pressure)
+ regs_needed[0] = 0;
+ else
+ {
+ for (i = 0; i < ira_pressure_classes_num; i++)
+ regs_needed[ira_pressure_classes[i]] = 0;
+ }
+
if (inv->move
|| inv->stamp == actual_stamp)
- return;
+ return -1;
inv->stamp = actual_stamp;
- (*regs_needed)++;
- (*comp_cost) += inv->cost;
+ if (! flag_ira_loop_pressure)
+ regs_needed[0]++;
+ else
+ {
+ int nregs;
+ enum reg_class pressure_class;
+
+ pressure_class = get_pressure_class_and_nregs (inv->insn, &nregs);
+ regs_needed[pressure_class] += nregs;
+ *cl = pressure_class;
+ ret = 0;
+ }
+
+ if (!inv->cheap_address
+ || inv->def->n_uses == 0
+ || inv->def->n_addr_uses < inv->def->n_uses)
+ (*comp_cost) += inv->cost * inv->eqno;
#ifdef STACK_REGS
{
on floating point constants is unlikely to ever occur. */
rtx set = single_set (inv->insn);
if (set
- && IS_STACK_MODE (GET_MODE (SET_SRC (set)))
- && constant_pool_constant_p (SET_SRC (set)))
- (*regs_needed) += 2;
+ && IS_STACK_MODE (GET_MODE (SET_SRC (set)))
+ && constant_pool_constant_p (SET_SRC (set)))
+ {
+ if (flag_ira_loop_pressure)
+ regs_needed[ira_stack_reg_pressure_class] += 2;
+ else
+ regs_needed[0] += 2;
+ }
}
#endif
EXECUTE_IF_SET_IN_BITMAP (inv->depends_on, 0, depno, bi)
{
- dep = VEC_index (invariant_p, invariants, depno);
+ bool check_p;
+ enum reg_class dep_cl = ALL_REGS;
+ int dep_ret;
- get_inv_cost (dep, &acomp_cost, &aregs_needed);
+ dep = invariants[depno];
- if (aregs_needed
+ /* If DEP is moved out of the loop, it is not a depends_on any more. */
+ if (dep->move)
+ continue;
+
+ dep_ret = get_inv_cost (dep, &acomp_cost, aregs_needed, &dep_cl);
+
+ if (! flag_ira_loop_pressure)
+ check_p = aregs_needed[0] != 0;
+ else
+ {
+ for (i = 0; i < ira_pressure_classes_num; i++)
+ if (aregs_needed[ira_pressure_classes[i]] != 0)
+ break;
+ check_p = i < ira_pressure_classes_num;
+
+ if ((dep_ret == 1) || ((dep_ret == 0) && (*cl != dep_cl)))
+ {
+ *cl = ALL_REGS;
+ ret = 1;
+ }
+ }
+ if (check_p
/* We need to check always_executed, since if the original value of
the invariant may be preserved, we may need to keep it in a
separate register. TODO check whether the register has an
{
/* If this is a single use, after moving the dependency we will not
need a new register. */
- aregs_needed--;
+ if (! flag_ira_loop_pressure)
+ aregs_needed[0]--;
+ else
+ {
+ int nregs;
+ enum reg_class pressure_class;
+
+ pressure_class = get_pressure_class_and_nregs (inv->insn, &nregs);
+ aregs_needed[pressure_class] -= nregs;
+ }
}
- (*regs_needed) += aregs_needed;
+ if (! flag_ira_loop_pressure)
+ regs_needed[0] += aregs_needed[0];
+ else
+ {
+ for (i = 0; i < ira_pressure_classes_num; i++)
+ regs_needed[ira_pressure_classes[i]]
+ += aregs_needed[ira_pressure_classes[i]];
+ }
(*comp_cost) += acomp_cost;
}
+ return ret;
}
/* Calculates gain for eliminating invariant INV. REGS_USED is the number
- of registers used in the loop, N_INV_USES is the number of uses of
- invariants, NEW_REGS is the number of new variables already added due to
- the invariant motion. The number of registers needed for it is stored in
- *REGS_NEEDED. */
+ of registers used in the loop, NEW_REGS is the number of new variables
+ already added due to the invariant motion. The number of registers needed
+ for it is stored in *REGS_NEEDED. SPEED and CALL_P are flags passed
+ through to estimate_reg_pressure_cost. */
static int
gain_for_invariant (struct invariant *inv, unsigned *regs_needed,
- unsigned new_regs, unsigned regs_used, unsigned n_inv_uses)
+ unsigned *new_regs, unsigned regs_used,
+ bool speed, bool call_p)
{
int comp_cost, size_cost;
+ /* Workaround -Wmaybe-uninitialized false positive during
+ profiledbootstrap by initializing it. */
+ enum reg_class cl = NO_REGS;
+ int ret;
- get_inv_cost (inv, &comp_cost, regs_needed);
actual_stamp++;
- size_cost = (global_cost_for_size (new_regs + *regs_needed,
- regs_used, n_inv_uses)
- - global_cost_for_size (new_regs, regs_used, n_inv_uses));
+ ret = get_inv_cost (inv, &comp_cost, regs_needed, &cl);
+
+ if (! flag_ira_loop_pressure)
+ {
+ size_cost = (estimate_reg_pressure_cost (new_regs[0] + regs_needed[0],
+ regs_used, speed, call_p)
+ - estimate_reg_pressure_cost (new_regs[0],
+ regs_used, speed, call_p));
+ }
+ else if (ret < 0)
+ return -1;
+ else if ((ret == 0) && (cl == NO_REGS))
+ /* Hoist it anyway since it does not impact register pressure. */
+ return 1;
+ else
+ {
+ int i;
+ enum reg_class pressure_class;
+
+ for (i = 0; i < ira_pressure_classes_num; i++)
+ {
+ pressure_class = ira_pressure_classes[i];
+
+ if (!reg_classes_intersect_p (pressure_class, cl))
+ continue;
+
+ if ((int) new_regs[pressure_class]
+ + (int) regs_needed[pressure_class]
+ + LOOP_DATA (curr_loop)->max_reg_pressure[pressure_class]
+ + IRA_LOOP_RESERVED_REGS
+ > ira_class_hard_regs_num[pressure_class])
+ break;
+ }
+ if (i < ira_pressure_classes_num)
+ /* There will be register pressure excess and we want not to
+ make this loop invariant motion. All loop invariants with
+ non-positive gains will be rejected in function
+ find_invariants_to_move. Therefore we return the negative
+ number here.
+
+ One could think that this rejects also expensive loop
+ invariant motions and this will hurt code performance.
+ However numerous experiments with different heuristics
+ taking invariant cost into account did not confirm this
+ assumption. There are possible explanations for this
+ result:
+ o probably all expensive invariants were already moved out
+ of the loop by PRE and gimple invariant motion pass.
+ o expensive invariant execution will be hidden by insn
+ scheduling or OOO processor hardware because usually such
+ invariants have a lot of freedom to be executed
+ out-of-order.
+ Another reason for ignoring invariant cost vs spilling cost
+ heuristics is also in difficulties to evaluate accurately
+ spill cost at this stage. */
+ return -1;
+ else
+ size_cost = 0;
+ }
return comp_cost - size_cost;
}
/* Finds invariant with best gain for moving. Returns the gain, stores
the invariant in *BEST and number of registers needed for it to
- *REGS_NEEDED. REGS_USED is the number of registers used in
- the loop, N_INV_USES is the number of uses of invariants. NEW_REGS
- is the number of new variables already added due to invariant motion. */
+ *REGS_NEEDED. REGS_USED is the number of registers used in the loop.
+ NEW_REGS is the number of new variables already added due to invariant
+ motion. */
static int
best_gain_for_invariant (struct invariant **best, unsigned *regs_needed,
- unsigned new_regs, unsigned regs_used,
- unsigned n_inv_uses)
+ unsigned *new_regs, unsigned regs_used,
+ bool speed, bool call_p)
{
struct invariant *inv;
- int gain = 0, again;
- unsigned aregs_needed, invno;
+ int i, gain = 0, again;
+ unsigned aregs_needed[N_REG_CLASSES], invno;
- for (invno = 0; VEC_iterate (invariant_p, invariants, invno, inv); invno++)
+ FOR_EACH_VEC_ELT (invariants, invno, inv)
{
if (inv->move)
continue;
if (inv->eqto != inv->invno)
continue;
- again = gain_for_invariant (inv, &aregs_needed,
- new_regs, regs_used, n_inv_uses);
+ again = gain_for_invariant (inv, aregs_needed, new_regs, regs_used,
+ speed, call_p);
if (again > gain)
{
gain = again;
*best = inv;
- *regs_needed = aregs_needed;
+ if (! flag_ira_loop_pressure)
+ regs_needed[0] = aregs_needed[0];
+ else
+ {
+ for (i = 0; i < ira_pressure_classes_num; i++)
+ regs_needed[ira_pressure_classes[i]]
+ = aregs_needed[ira_pressure_classes[i]];
+ }
}
}
/* Marks invariant INVNO and all its dependencies for moving. */
static void
-set_move_mark (unsigned invno)
+set_move_mark (unsigned invno, int gain)
{
- struct invariant *inv = VEC_index (invariant_p, invariants, invno);
+ struct invariant *inv = invariants[invno];
bitmap_iterator bi;
/* Find the representative of the class of the equivalent invariants. */
- inv = VEC_index (invariant_p, invariants, inv->eqto);
+ inv = invariants[inv->eqto];
if (inv->move)
return;
inv->move = true;
if (dump_file)
- fprintf (dump_file, "Decided to move invariant %d\n", invno);
+ {
+ if (gain >= 0)
+ fprintf (dump_file, "Decided to move invariant %d -- gain %d\n",
+ invno, gain);
+ else
+ fprintf (dump_file, "Decided to move dependent invariant %d\n",
+ invno);
+ };
EXECUTE_IF_SET_IN_BITMAP (inv->depends_on, 0, invno, bi)
{
- set_move_mark (invno);
+ set_move_mark (invno, -1);
}
}
/* Determines which invariants to move. */
static void
-find_invariants_to_move (void)
+find_invariants_to_move (bool speed, bool call_p)
{
- unsigned i, regs_used, n_inv_uses, regs_needed = 0, new_regs;
+ int gain;
+ unsigned i, regs_used, regs_needed[N_REG_CLASSES], new_regs[N_REG_CLASSES];
struct invariant *inv = NULL;
- unsigned int n_regs = DF_REG_SIZE (df);
- if (!VEC_length (invariant_p, invariants))
+ if (!invariants.length ())
return;
- /* Now something slightly more involved. First estimate the number of used
- registers. */
- n_inv_uses = 0;
+ if (flag_ira_loop_pressure)
+ /* REGS_USED is actually never used when the flag is on. */
+ regs_used = 0;
+ else
+ /* We do not really do a good job in estimating number of
+ registers used; we put some initial bound here to stand for
+ induction variables etc. that we do not detect. */
+ {
+ unsigned int n_regs = DF_REG_SIZE (df);
- /* We do not really do a good job in this estimation; put some initial bound
- here to stand for induction variables etc. that we do not detect. */
- regs_used = 2;
+ regs_used = 2;
- for (i = 0; i < n_regs; i++)
- {
- if (!DF_REGNO_FIRST_DEF (df, i) && DF_REGNO_LAST_USE (df, i))
+ for (i = 0; i < n_regs; i++)
{
- /* This is a value that is used but not changed inside loop. */
- regs_used++;
+ if (!DF_REGNO_FIRST_DEF (i) && DF_REGNO_LAST_USE (i))
+ {
+ /* This is a value that is used but not changed inside loop. */
+ regs_used++;
+ }
}
}
- for (i = 0; VEC_iterate (invariant_p, invariants, i, inv); i++)
+ if (! flag_ira_loop_pressure)
+ new_regs[0] = regs_needed[0] = 0;
+ else
+ {
+ for (i = 0; (int) i < ira_pressure_classes_num; i++)
+ new_regs[ira_pressure_classes[i]] = 0;
+ }
+ while ((gain = best_gain_for_invariant (&inv, regs_needed,
+ new_regs, regs_used,
+ speed, call_p)) > 0)
{
- if (inv->def)
- n_inv_uses += inv->def->n_uses;
+ set_move_mark (inv->invno, gain);
+ if (! flag_ira_loop_pressure)
+ new_regs[0] += regs_needed[0];
+ else
+ {
+ for (i = 0; (int) i < ira_pressure_classes_num; i++)
+ new_regs[ira_pressure_classes[i]]
+ += regs_needed[ira_pressure_classes[i]];
+ }
}
+}
- new_regs = 0;
- while (best_gain_for_invariant (&inv, ®s_needed,
- new_regs, regs_used, n_inv_uses) > 0)
+/* Replace the uses, reached by the definition of invariant INV, by REG.
+
+ IN_GROUP is nonzero if this is part of a group of changes that must be
+ performed as a group. In that case, the changes will be stored. The
+ function `apply_change_group' will validate and apply the changes. */
+
+static int
+replace_uses (struct invariant *inv, rtx reg, bool in_group)
+{
+ /* Replace the uses we know to be dominated. It saves work for copy
+ propagation, and also it is necessary so that dependent invariants
+ are computed right. */
+ if (inv->def)
{
- set_move_mark (inv->invno);
- new_regs += regs_needed;
+ struct use *use;
+ for (use = inv->def->uses; use; use = use->next)
+ validate_change (use->insn, use->pos, reg, true);
+
+ /* If we aren't part of a larger group, apply the changes now. */
+ if (!in_group)
+ return apply_change_group ();
}
+
+ return 1;
}
-/* Returns true if all insns in SEQ are valid. */
+/* Whether invariant INV setting REG can be moved out of LOOP, at the end of
+ the block preceding its header. */
static bool
-seq_insns_valid_p (rtx seq)
+can_move_invariant_reg (struct loop *loop, struct invariant *inv, rtx reg)
{
- rtx x;
+ df_ref def, use;
+ unsigned int dest_regno, defs_in_loop_count = 0;
+ rtx_insn *insn = inv->insn;
+ basic_block bb = BLOCK_FOR_INSN (inv->insn);
+
+ /* We ignore hard register and memory access for cost and complexity reasons.
+ Hard register are few at this stage and expensive to consider as they
+ require building a separate data flow. Memory access would require using
+ df_simulate_* and can_move_insns_across functions and is more complex. */
+ if (!REG_P (reg) || HARD_REGISTER_P (reg))
+ return false;
- for (x = seq; x; x = NEXT_INSN (x))
- if (insn_invalid_p (x))
- return false;
+ /* Check whether the set is always executed. We could omit this condition if
+ we know that the register is unused outside of the loop, but it does not
+ seem worth finding out. */
+ if (!inv->always_executed)
+ return false;
+
+ /* Check that all uses that would be dominated by def are already dominated
+ by it. */
+ dest_regno = REGNO (reg);
+ for (use = DF_REG_USE_CHAIN (dest_regno); use; use = DF_REF_NEXT_REG (use))
+ {
+ rtx_insn *use_insn;
+ basic_block use_bb;
+
+ use_insn = DF_REF_INSN (use);
+ use_bb = BLOCK_FOR_INSN (use_insn);
+
+ /* Ignore instruction considered for moving. */
+ if (use_insn == insn)
+ continue;
+
+ /* Don't consider uses outside loop. */
+ if (!flow_bb_inside_loop_p (loop, use_bb))
+ continue;
+
+ /* Don't move if a use is not dominated by def in insn. */
+ if (use_bb == bb && DF_INSN_LUID (insn) >= DF_INSN_LUID (use_insn))
+ return false;
+ if (!dominated_by_p (CDI_DOMINATORS, use_bb, bb))
+ return false;
+ }
+
+ /* Check for other defs. Any other def in the loop might reach a use
+ currently reached by the def in insn. */
+ for (def = DF_REG_DEF_CHAIN (dest_regno); def; def = DF_REF_NEXT_REG (def))
+ {
+ basic_block def_bb = DF_REF_BB (def);
+
+ /* Defs in exit block cannot reach a use they weren't already. */
+ if (single_succ_p (def_bb))
+ {
+ basic_block def_bb_succ;
+
+ def_bb_succ = single_succ (def_bb);
+ if (!flow_bb_inside_loop_p (loop, def_bb_succ))
+ continue;
+ }
+
+ if (++defs_in_loop_count > 1)
+ return false;
+ }
return true;
}
static bool
move_invariant_reg (struct loop *loop, unsigned invno)
{
- struct invariant *inv = VEC_index (invariant_p, invariants, invno);
- struct invariant *repr = VEC_index (invariant_p, invariants, inv->eqto);
+ struct invariant *inv = invariants[invno];
+ struct invariant *repr = invariants[inv->eqto];
unsigned i;
basic_block preheader = loop_preheader_edge (loop)->src;
- rtx reg, set, dest, seq, op;
- struct use *use;
+ rtx reg, set, dest, note;
bitmap_iterator bi;
+ int regno = -1;
if (inv->reg)
return true;
}
}
- /* Move the set out of the loop. If the set is always executed (we could
- omit this condition if we know that the register is unused outside of the
- loop, but it does not seem worth finding out) and it has no uses that
- would not be dominated by it, we may just move it (TODO). Otherwise we
+ /* If possible, just move the set out of the loop. Otherwise, we
need to create a temporary register. */
set = single_set (inv->insn);
- dest = SET_DEST (set);
- reg = gen_reg_rtx (GET_MODE (dest));
+ reg = dest = SET_DEST (set);
+ if (GET_CODE (reg) == SUBREG)
+ reg = SUBREG_REG (reg);
+ if (REG_P (reg))
+ regno = REGNO (reg);
- /* If the SET_DEST of the invariant insn is a pseudo, we can just move
- the insn out of the loop. Otherwise, we have to use gen_move_insn
- to let emit_move_insn produce a valid instruction stream. */
- if (REG_P (dest) && !HARD_REGISTER_P (dest))
- {
- emit_insn_after (gen_move_insn (dest, reg), inv->insn);
- SET_DEST (set) = reg;
- reorder_insns (inv->insn, inv->insn, BB_END (preheader));
- }
- else
+ if (!can_move_invariant_reg (loop, inv, reg))
{
- start_sequence ();
- op = force_operand (SET_SRC (set), reg);
- if (op != reg)
- emit_move_insn (reg, op);
- seq = get_insns ();
- end_sequence ();
-
- if (!seq_insns_valid_p (seq))
+ reg = gen_reg_rtx_and_attrs (dest);
+
+ /* Try replacing the destination by a new pseudoregister. */
+ validate_change (inv->insn, &SET_DEST (set), reg, true);
+
+ /* As well as all the dominated uses. */
+ replace_uses (inv, reg, true);
+
+ /* And validate all the changes. */
+ if (!apply_change_group ())
goto fail;
- emit_insn_after (seq, BB_END (preheader));
-
+
emit_insn_after (gen_move_insn (dest, reg), inv->insn);
- delete_insn (inv->insn);
}
+ else if (dump_file)
+ fprintf (dump_file, "Invariant %d moved without introducing a new "
+ "temporary register\n", invno);
+ reorder_insns (inv->insn, inv->insn, BB_END (preheader));
+
+ /* If there is a REG_EQUAL note on the insn we just moved, and the
+ insn is in a basic block that is not always executed or the note
+ contains something for which we don't know the invariant status,
+ the note may no longer be valid after we move the insn. Note that
+ uses in REG_EQUAL notes are taken into account in the computation
+ of invariants, so it is safe to retain the note even if it contains
+ register references for which we know the invariant status. */
+ if ((note = find_reg_note (inv->insn, REG_EQUAL, NULL_RTX))
+ && (!inv->always_executed
+ || !check_maybe_invariant (XEXP (note, 0))))
+ remove_note (inv->insn, note);
}
else
{
if (!move_invariant_reg (loop, repr->invno))
goto fail;
reg = repr->reg;
+ regno = repr->orig_regno;
+ if (!replace_uses (inv, reg, false))
+ goto fail;
set = single_set (inv->insn);
emit_insn_after (gen_move_insn (SET_DEST (set), reg), inv->insn);
delete_insn (inv->insn);
}
inv->reg = reg;
-
- /* Replace the uses we know to be dominated. It saves work for copy
- propagation, and also it is necessary so that dependent invariants
- are computed right. */
- if (inv->def)
- {
- for (use = inv->def->uses; use; use = use->next)
- *use->pos = reg;
- }
+ inv->orig_regno = regno;
return true;
fprintf (dump_file, "Failed to move invariant %d\n", invno);
inv->move = false;
inv->reg = NULL_RTX;
+ inv->orig_regno = -1;
+
return false;
}
struct invariant *inv;
unsigned i;
- for (i = 0; VEC_iterate (invariant_p, invariants, i, inv); i++)
+ FOR_EACH_VEC_ELT (invariants, i, inv)
move_invariant_reg (loop, i);
+ if (flag_ira_loop_pressure && resize_reg_info ())
+ {
+ FOR_EACH_VEC_ELT (invariants, i, inv)
+ if (inv->reg != NULL_RTX)
+ {
+ if (inv->orig_regno >= 0)
+ setup_reg_classes (REGNO (inv->reg),
+ reg_preferred_class (inv->orig_regno),
+ reg_alternate_class (inv->orig_regno),
+ reg_allocno_class (inv->orig_regno));
+ else
+ setup_reg_classes (REGNO (inv->reg),
+ GENERAL_REGS, NO_REGS, GENERAL_REGS);
+ }
+ }
}
/* Initializes invariant motion data. */
{
actual_stamp = 1;
- invariants = VEC_alloc (invariant_p, heap, 100);
+ invariants.create (100);
}
/* Frees the data allocated by invariant motion. */
struct def *def;
struct invariant *inv;
- for (i = 0; i < DF_DEFS_SIZE (df); i++)
+ check_invariant_table_size ();
+ for (i = 0; i < DF_DEFS_TABLE_SIZE (); i++)
{
- struct df_ref * ref = DF_DEFS_GET (df, i);
- if (!ref)
- continue;
-
- inv = DF_REF_DATA (ref);
- if (!inv)
- continue;
-
- def = inv->def;
- gcc_assert (def != NULL);
+ inv = invariant_table[i];
+ if (inv)
+ {
+ def = inv->def;
+ gcc_assert (def != NULL);
- free_use_list (def->uses);
- free (def);
- DF_REF_DATA (ref) = NULL;
+ free_use_list (def->uses);
+ free (def);
+ invariant_table[i] = NULL;
+ }
}
- for (i = 0; VEC_iterate (invariant_p, invariants, i, inv); i++)
+ FOR_EACH_VEC_ELT (invariants, i, inv)
{
BITMAP_FREE (inv->depends_on);
free (inv);
}
- VEC_free (invariant_p, heap, invariants);
+ invariants.release ();
}
/* Move the invariants out of the LOOP. */
init_inv_motion_data ();
find_invariants (loop);
- find_invariants_to_move ();
+ find_invariants_to_move (optimize_loop_for_speed_p (loop),
+ LOOP_DATA (loop)->has_call);
move_invariants (loop);
free_inv_motion_data ();
free_loop_data (struct loop *loop)
{
struct loop_data *data = LOOP_DATA (loop);
+ if (!data)
+ return;
+ bitmap_clear (&LOOP_DATA (loop)->regs_ref);
+ bitmap_clear (&LOOP_DATA (loop)->regs_live);
free (data);
loop->aux = NULL;
}
-/* Move the invariants out of the LOOPS. */
+\f
-void
-move_loop_invariants (struct loops *loops)
+/* Registers currently living. */
+static bitmap_head curr_regs_live;
+
+/* Current reg pressure for each pressure class. */
+static int curr_reg_pressure[N_REG_CLASSES];
+
+/* Record all regs that are set in any one insn. Communication from
+ mark_reg_{store,clobber} and global_conflicts. Asm can refer to
+ all hard-registers. */
+static rtx regs_set[(FIRST_PSEUDO_REGISTER > MAX_RECOG_OPERANDS
+ ? FIRST_PSEUDO_REGISTER : MAX_RECOG_OPERANDS) * 2];
+/* Number of regs stored in the previous array. */
+static int n_regs_set;
+
+/* Return pressure class and number of needed hard registers (through
+ *NREGS) of register REGNO. */
+static enum reg_class
+get_regno_pressure_class (int regno, int *nregs)
+{
+ if (regno >= FIRST_PSEUDO_REGISTER)
+ {
+ enum reg_class pressure_class;
+
+ pressure_class = reg_allocno_class (regno);
+ pressure_class = ira_pressure_class_translate[pressure_class];
+ *nregs
+ = ira_reg_class_max_nregs[pressure_class][PSEUDO_REGNO_MODE (regno)];
+ return pressure_class;
+ }
+ else if (! TEST_HARD_REG_BIT (ira_no_alloc_regs, regno)
+ && ! TEST_HARD_REG_BIT (eliminable_regset, regno))
+ {
+ *nregs = 1;
+ return ira_pressure_class_translate[REGNO_REG_CLASS (regno)];
+ }
+ else
+ {
+ *nregs = 0;
+ return NO_REGS;
+ }
+}
+
+/* Increase (if INCR_P) or decrease current register pressure for
+ register REGNO. */
+static void
+change_pressure (int regno, bool incr_p)
+{
+ int nregs;
+ enum reg_class pressure_class;
+
+ pressure_class = get_regno_pressure_class (regno, &nregs);
+ if (! incr_p)
+ curr_reg_pressure[pressure_class] -= nregs;
+ else
+ {
+ curr_reg_pressure[pressure_class] += nregs;
+ if (LOOP_DATA (curr_loop)->max_reg_pressure[pressure_class]
+ < curr_reg_pressure[pressure_class])
+ LOOP_DATA (curr_loop)->max_reg_pressure[pressure_class]
+ = curr_reg_pressure[pressure_class];
+ }
+}
+
+/* Mark REGNO birth. */
+static void
+mark_regno_live (int regno)
{
struct loop *loop;
- unsigned i;
- df = df_init (DF_HARD_REGS | DF_EQUIV_NOTES);
- df_chain_add_problem (df, DF_UD_CHAIN);
-
- /* Process the loops, innermost first. */
- loop = loops->tree_root;
- while (loop->inner)
- loop = loop->inner;
+ for (loop = curr_loop;
+ loop != current_loops->tree_root;
+ loop = loop_outer (loop))
+ bitmap_set_bit (&LOOP_DATA (loop)->regs_live, regno);
+ if (!bitmap_set_bit (&curr_regs_live, regno))
+ return;
+ change_pressure (regno, true);
+}
+
+/* Mark REGNO death. */
+static void
+mark_regno_death (int regno)
+{
+ if (! bitmap_clear_bit (&curr_regs_live, regno))
+ return;
+ change_pressure (regno, false);
+}
+
+/* Mark setting register REG. */
+static void
+mark_reg_store (rtx reg, const_rtx setter ATTRIBUTE_UNUSED,
+ void *data ATTRIBUTE_UNUSED)
+{
+ if (GET_CODE (reg) == SUBREG)
+ reg = SUBREG_REG (reg);
+
+ if (! REG_P (reg))
+ return;
+
+ regs_set[n_regs_set++] = reg;
+
+ unsigned int end_regno = END_REGNO (reg);
+ for (unsigned int regno = REGNO (reg); regno < end_regno; ++regno)
+ mark_regno_live (regno);
+}
+
+/* Mark clobbering register REG. */
+static void
+mark_reg_clobber (rtx reg, const_rtx setter, void *data)
+{
+ if (GET_CODE (setter) == CLOBBER)
+ mark_reg_store (reg, setter, data);
+}
+
+/* Mark register REG death. */
+static void
+mark_reg_death (rtx reg)
+{
+ unsigned int end_regno = END_REGNO (reg);
+ for (unsigned int regno = REGNO (reg); regno < end_regno; ++regno)
+ mark_regno_death (regno);
+}
+
+/* Mark occurrence of registers in X for the current loop. */
+static void
+mark_ref_regs (rtx x)
+{
+ RTX_CODE code;
+ int i;
+ const char *fmt;
+
+ if (!x)
+ return;
+
+ code = GET_CODE (x);
+ if (code == REG)
+ {
+ struct loop *loop;
+
+ for (loop = curr_loop;
+ loop != current_loops->tree_root;
+ loop = loop_outer (loop))
+ bitmap_set_bit (&LOOP_DATA (loop)->regs_ref, REGNO (x));
+ return;
+ }
+
+ fmt = GET_RTX_FORMAT (code);
+ for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
+ if (fmt[i] == 'e')
+ mark_ref_regs (XEXP (x, i));
+ else if (fmt[i] == 'E')
+ {
+ int j;
+
+ for (j = 0; j < XVECLEN (x, i); j++)
+ mark_ref_regs (XVECEXP (x, i, j));
+ }
+}
- while (loop != loops->tree_root)
+/* Calculate register pressure in the loops. */
+static void
+calculate_loop_reg_pressure (void)
+{
+ int i;
+ unsigned int j;
+ bitmap_iterator bi;
+ basic_block bb;
+ rtx_insn *insn;
+ rtx link;
+ struct loop *loop, *parent;
+
+ FOR_EACH_LOOP (loop, 0)
+ if (loop->aux == NULL)
+ {
+ loop->aux = xcalloc (1, sizeof (struct loop_data));
+ bitmap_initialize (&LOOP_DATA (loop)->regs_ref, ®_obstack);
+ bitmap_initialize (&LOOP_DATA (loop)->regs_live, ®_obstack);
+ }
+ ira_setup_eliminable_regset ();
+ bitmap_initialize (&curr_regs_live, ®_obstack);
+ FOR_EACH_BB_FN (bb, cfun)
{
- move_single_loop_invariants (loop);
+ curr_loop = bb->loop_father;
+ if (curr_loop == current_loops->tree_root)
+ continue;
+
+ for (loop = curr_loop;
+ loop != current_loops->tree_root;
+ loop = loop_outer (loop))
+ bitmap_ior_into (&LOOP_DATA (loop)->regs_live, DF_LR_IN (bb));
+
+ bitmap_copy (&curr_regs_live, DF_LR_IN (bb));
+ for (i = 0; i < ira_pressure_classes_num; i++)
+ curr_reg_pressure[ira_pressure_classes[i]] = 0;
+ EXECUTE_IF_SET_IN_BITMAP (&curr_regs_live, 0, j, bi)
+ change_pressure (j, true);
- if (loop->next)
+ FOR_BB_INSNS (bb, insn)
{
- loop = loop->next;
- while (loop->inner)
- loop = loop->inner;
+ if (! NONDEBUG_INSN_P (insn))
+ continue;
+
+ mark_ref_regs (PATTERN (insn));
+ n_regs_set = 0;
+ note_stores (PATTERN (insn), mark_reg_clobber, NULL);
+
+ /* Mark any registers dead after INSN as dead now. */
+
+ for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
+ if (REG_NOTE_KIND (link) == REG_DEAD)
+ mark_reg_death (XEXP (link, 0));
+
+ /* Mark any registers set in INSN as live,
+ and mark them as conflicting with all other live regs.
+ Clobbers are processed again, so they conflict with
+ the registers that are set. */
+
+ note_stores (PATTERN (insn), mark_reg_store, NULL);
+
+#ifdef AUTO_INC_DEC
+ for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
+ if (REG_NOTE_KIND (link) == REG_INC)
+ mark_reg_store (XEXP (link, 0), NULL_RTX, NULL);
+#endif
+ while (n_regs_set-- > 0)
+ {
+ rtx note = find_regno_note (insn, REG_UNUSED,
+ REGNO (regs_set[n_regs_set]));
+ if (! note)
+ continue;
+
+ mark_reg_death (XEXP (note, 0));
+ }
}
- else
- loop = loop->outer;
}
+ bitmap_clear (&curr_regs_live);
+ if (flag_ira_region == IRA_REGION_MIXED
+ || flag_ira_region == IRA_REGION_ALL)
+ FOR_EACH_LOOP (loop, 0)
+ {
+ EXECUTE_IF_SET_IN_BITMAP (&LOOP_DATA (loop)->regs_live, 0, j, bi)
+ if (! bitmap_bit_p (&LOOP_DATA (loop)->regs_ref, j))
+ {
+ enum reg_class pressure_class;
+ int nregs;
+
+ pressure_class = get_regno_pressure_class (j, &nregs);
+ LOOP_DATA (loop)->max_reg_pressure[pressure_class] -= nregs;
+ }
+ }
+ if (dump_file == NULL)
+ return;
+ FOR_EACH_LOOP (loop, 0)
+ {
+ parent = loop_outer (loop);
+ fprintf (dump_file, "\n Loop %d (parent %d, header bb%d, depth %d)\n",
+ loop->num, (parent == NULL ? -1 : parent->num),
+ loop->header->index, loop_depth (loop));
+ fprintf (dump_file, "\n ref. regnos:");
+ EXECUTE_IF_SET_IN_BITMAP (&LOOP_DATA (loop)->regs_ref, 0, j, bi)
+ fprintf (dump_file, " %d", j);
+ fprintf (dump_file, "\n live regnos:");
+ EXECUTE_IF_SET_IN_BITMAP (&LOOP_DATA (loop)->regs_live, 0, j, bi)
+ fprintf (dump_file, " %d", j);
+ fprintf (dump_file, "\n Pressure:");
+ for (i = 0; (int) i < ira_pressure_classes_num; i++)
+ {
+ enum reg_class pressure_class;
+
+ pressure_class = ira_pressure_classes[i];
+ if (LOOP_DATA (loop)->max_reg_pressure[pressure_class] == 0)
+ continue;
+ fprintf (dump_file, " %s=%d", reg_class_names[pressure_class],
+ LOOP_DATA (loop)->max_reg_pressure[pressure_class]);
+ }
+ fprintf (dump_file, "\n");
+ }
+}
+
+\f
+
+/* Move the invariants out of the loops. */
- for (i = 1; i < loops->num; i++)
- if (loops->parray[i])
- free_loop_data (loops->parray[i]);
+void
+move_loop_invariants (void)
+{
+ struct loop *loop;
+
+ if (flag_ira_loop_pressure)
+ {
+ df_analyze ();
+ regstat_init_n_sets_and_refs ();
+ ira_set_pseudo_classes (true, dump_file);
+ calculate_loop_reg_pressure ();
+ regstat_free_n_sets_and_refs ();
+ }
+ df_set_flags (DF_EQ_NOTES + DF_DEFER_INSN_RESCAN);
+ /* Process the loops, innermost first. */
+ FOR_EACH_LOOP (loop, LI_FROM_INNERMOST)
+ {
+ curr_loop = loop;
+ /* move_single_loop_invariants for very large loops
+ is time consuming and might need a lot of memory. */
+ if (loop->num_nodes <= (unsigned) LOOP_INVARIANT_MAX_BBS_IN_LOOP)
+ move_single_loop_invariants (loop);
+ }
+
+ FOR_EACH_LOOP (loop, 0)
+ {
+ free_loop_data (loop);
+ }
- df_finish (df);
- df = NULL;
+ if (flag_ira_loop_pressure)
+ /* There is no sense to keep this info because it was most
+ probably outdated by subsequent passes. */
+ free_reg_info ();
+ free (invariant_table);
+ invariant_table = NULL;
+ invariant_table_size = 0;
#ifdef ENABLE_CHECKING
verify_flow_info ();
projects / gcc.git / blobdiff