/* Loop invariant motion.
|
/* Loop invariant motion.
|
Copyright (C) 2003, 2004, 2005, 2007 Free Software Foundation, Inc.
|
Copyright (C) 2003, 2004, 2005, 2007 Free Software Foundation, Inc.
|
|
|
This file is part of GCC.
|
This file is part of GCC.
|
|
|
GCC is free software; you can redistribute it and/or modify it
|
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
|
under the terms of the GNU General Public License as published by the
|
Free Software Foundation; either version 3, or (at your option) any
|
Free Software Foundation; either version 3, or (at your option) any
|
later version.
|
later version.
|
|
|
GCC is distributed in the hope that it will be useful, but WITHOUT
|
GCC is distributed in the hope that it will be useful, but WITHOUT
|
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
for more details.
|
for more details.
|
|
|
You should have received a copy of the GNU General Public License
|
You should have received a copy of the GNU General Public License
|
along with GCC; see the file COPYING3. If not see
|
along with GCC; see the file COPYING3. If not see
|
<http://www.gnu.org/licenses/>. */
|
<http://www.gnu.org/licenses/>. */
|
|
|
#include "config.h"
|
#include "config.h"
|
#include "system.h"
|
#include "system.h"
|
#include "coretypes.h"
|
#include "coretypes.h"
|
#include "tm.h"
|
#include "tm.h"
|
#include "tree.h"
|
#include "tree.h"
|
#include "rtl.h"
|
#include "rtl.h"
|
#include "tm_p.h"
|
#include "tm_p.h"
|
#include "hard-reg-set.h"
|
#include "hard-reg-set.h"
|
#include "basic-block.h"
|
#include "basic-block.h"
|
#include "output.h"
|
#include "output.h"
|
#include "diagnostic.h"
|
#include "diagnostic.h"
|
#include "tree-flow.h"
|
#include "tree-flow.h"
|
#include "tree-dump.h"
|
#include "tree-dump.h"
|
#include "timevar.h"
|
#include "timevar.h"
|
#include "cfgloop.h"
|
#include "cfgloop.h"
|
#include "domwalk.h"
|
#include "domwalk.h"
|
#include "params.h"
|
#include "params.h"
|
#include "tree-pass.h"
|
#include "tree-pass.h"
|
#include "flags.h"
|
#include "flags.h"
|
#include "real.h"
|
#include "real.h"
|
#include "hashtab.h"
|
#include "hashtab.h"
|
|
|
/* TODO: Support for predicated code motion. I.e.
|
/* TODO: Support for predicated code motion. I.e.
|
|
|
while (1)
|
while (1)
|
{
|
{
|
if (cond)
|
if (cond)
|
{
|
{
|
a = inv;
|
a = inv;
|
something;
|
something;
|
}
|
}
|
}
|
}
|
|
|
Where COND and INV are is invariants, but evaluating INV may trap or be
|
Where COND and INV are is invariants, but evaluating INV may trap or be
|
invalid from some other reason if !COND. This may be transformed to
|
invalid from some other reason if !COND. This may be transformed to
|
|
|
if (cond)
|
if (cond)
|
a = inv;
|
a = inv;
|
while (1)
|
while (1)
|
{
|
{
|
if (cond)
|
if (cond)
|
something;
|
something;
|
} */
|
} */
|
|
|
/* A type for the list of statements that have to be moved in order to be able
|
/* A type for the list of statements that have to be moved in order to be able
|
to hoist an invariant computation. */
|
to hoist an invariant computation. */
|
|
|
struct depend
|
struct depend
|
{
|
{
|
tree stmt;
|
tree stmt;
|
struct depend *next;
|
struct depend *next;
|
};
|
};
|
|
|
/* The auxiliary data kept for each statement. */
|
/* The auxiliary data kept for each statement. */
|
|
|
struct lim_aux_data
|
struct lim_aux_data
|
{
|
{
|
struct loop *max_loop; /* The outermost loop in that the statement
|
struct loop *max_loop; /* The outermost loop in that the statement
|
is invariant. */
|
is invariant. */
|
|
|
struct loop *tgt_loop; /* The loop out of that we want to move the
|
struct loop *tgt_loop; /* The loop out of that we want to move the
|
invariant. */
|
invariant. */
|
|
|
struct loop *always_executed_in;
|
struct loop *always_executed_in;
|
/* The outermost loop for that we are sure
|
/* The outermost loop for that we are sure
|
the statement is executed if the loop
|
the statement is executed if the loop
|
is entered. */
|
is entered. */
|
|
|
bool sm_done; /* True iff the store motion for a memory
|
bool sm_done; /* True iff the store motion for a memory
|
reference in the statement has already
|
reference in the statement has already
|
been executed. */
|
been executed. */
|
|
|
unsigned cost; /* Cost of the computation performed by the
|
unsigned cost; /* Cost of the computation performed by the
|
statement. */
|
statement. */
|
|
|
struct depend *depends; /* List of statements that must be also hoisted
|
struct depend *depends; /* List of statements that must be also hoisted
|
out of the loop when this statement is
|
out of the loop when this statement is
|
hoisted; i.e. those that define the operands
|
hoisted; i.e. those that define the operands
|
of the statement and are inside of the
|
of the statement and are inside of the
|
MAX_LOOP loop. */
|
MAX_LOOP loop. */
|
};
|
};
|
|
|
#define LIM_DATA(STMT) (TREE_CODE (STMT) == PHI_NODE \
|
#define LIM_DATA(STMT) (TREE_CODE (STMT) == PHI_NODE \
|
? NULL \
|
? NULL \
|
: (struct lim_aux_data *) (stmt_ann (STMT)->common.aux))
|
: (struct lim_aux_data *) (stmt_ann (STMT)->common.aux))
|
|
|
/* Description of a memory reference location for store motion. */
|
/* Description of a memory reference location for store motion. */
|
|
|
struct mem_ref_loc
|
struct mem_ref_loc
|
{
|
{
|
tree *ref; /* The reference itself. */
|
tree *ref; /* The reference itself. */
|
tree stmt; /* The statement in that it occurs. */
|
tree stmt; /* The statement in that it occurs. */
|
struct mem_ref_loc *next; /* Next use in the chain. */
|
struct mem_ref_loc *next; /* Next use in the chain. */
|
};
|
};
|
|
|
/* Description of a memory reference for store motion. */
|
/* Description of a memory reference for store motion. */
|
|
|
struct mem_ref
|
struct mem_ref
|
{
|
{
|
tree mem; /* The memory itself. */
|
tree mem; /* The memory itself. */
|
hashval_t hash; /* Its hash value. */
|
hashval_t hash; /* Its hash value. */
|
bool is_stored; /* True if there is a store to the location
|
bool is_stored; /* True if there is a store to the location
|
in the loop. */
|
in the loop. */
|
struct mem_ref_loc *locs; /* The locations where it is found. */
|
struct mem_ref_loc *locs; /* The locations where it is found. */
|
bitmap vops; /* Vops corresponding to this memory
|
bitmap vops; /* Vops corresponding to this memory
|
location. */
|
location. */
|
struct mem_ref *next; /* Next memory reference in the list.
|
struct mem_ref *next; /* Next memory reference in the list.
|
Memory references are stored in a hash
|
Memory references are stored in a hash
|
table, but the hash function depends
|
table, but the hash function depends
|
on values of pointers. Thus we cannot use
|
on values of pointers. Thus we cannot use
|
htab_traverse, since then we would get
|
htab_traverse, since then we would get
|
miscompares during bootstrap (although the
|
miscompares during bootstrap (although the
|
produced code would be correct). */
|
produced code would be correct). */
|
};
|
};
|
|
|
/* Minimum cost of an expensive expression. */
|
/* Minimum cost of an expensive expression. */
|
#define LIM_EXPENSIVE ((unsigned) PARAM_VALUE (PARAM_LIM_EXPENSIVE))
|
#define LIM_EXPENSIVE ((unsigned) PARAM_VALUE (PARAM_LIM_EXPENSIVE))
|
|
|
/* The outermost loop for that execution of the header guarantees that the
|
/* The outermost loop for that execution of the header guarantees that the
|
block will be executed. */
|
block will be executed. */
|
#define ALWAYS_EXECUTED_IN(BB) ((struct loop *) (BB)->aux)
|
#define ALWAYS_EXECUTED_IN(BB) ((struct loop *) (BB)->aux)
|
|
|
/* Calls CBCK for each index in memory reference ADDR_P. There are two
|
/* Calls CBCK for each index in memory reference ADDR_P. There are two
|
kinds situations handled; in each of these cases, the memory reference
|
kinds situations handled; in each of these cases, the memory reference
|
and DATA are passed to the callback:
|
and DATA are passed to the callback:
|
|
|
Access to an array: ARRAY_{RANGE_}REF (base, index). In this case we also
|
Access to an array: ARRAY_{RANGE_}REF (base, index). In this case we also
|
pass the pointer to the index to the callback.
|
pass the pointer to the index to the callback.
|
|
|
Pointer dereference: INDIRECT_REF (addr). In this case we also pass the
|
Pointer dereference: INDIRECT_REF (addr). In this case we also pass the
|
pointer to addr to the callback.
|
pointer to addr to the callback.
|
|
|
If the callback returns false, the whole search stops and false is returned.
|
If the callback returns false, the whole search stops and false is returned.
|
Otherwise the function returns true after traversing through the whole
|
Otherwise the function returns true after traversing through the whole
|
reference *ADDR_P. */
|
reference *ADDR_P. */
|
|
|
bool
|
bool
|
for_each_index (tree *addr_p, bool (*cbck) (tree, tree *, void *), void *data)
|
for_each_index (tree *addr_p, bool (*cbck) (tree, tree *, void *), void *data)
|
{
|
{
|
tree *nxt, *idx;
|
tree *nxt, *idx;
|
|
|
for (; ; addr_p = nxt)
|
for (; ; addr_p = nxt)
|
{
|
{
|
switch (TREE_CODE (*addr_p))
|
switch (TREE_CODE (*addr_p))
|
{
|
{
|
case SSA_NAME:
|
case SSA_NAME:
|
return cbck (*addr_p, addr_p, data);
|
return cbck (*addr_p, addr_p, data);
|
|
|
case MISALIGNED_INDIRECT_REF:
|
case MISALIGNED_INDIRECT_REF:
|
case ALIGN_INDIRECT_REF:
|
case ALIGN_INDIRECT_REF:
|
case INDIRECT_REF:
|
case INDIRECT_REF:
|
nxt = &TREE_OPERAND (*addr_p, 0);
|
nxt = &TREE_OPERAND (*addr_p, 0);
|
return cbck (*addr_p, nxt, data);
|
return cbck (*addr_p, nxt, data);
|
|
|
case BIT_FIELD_REF:
|
case BIT_FIELD_REF:
|
case VIEW_CONVERT_EXPR:
|
case VIEW_CONVERT_EXPR:
|
case REALPART_EXPR:
|
case REALPART_EXPR:
|
case IMAGPART_EXPR:
|
case IMAGPART_EXPR:
|
nxt = &TREE_OPERAND (*addr_p, 0);
|
nxt = &TREE_OPERAND (*addr_p, 0);
|
break;
|
break;
|
|
|
case COMPONENT_REF:
|
case COMPONENT_REF:
|
/* If the component has varying offset, it behaves like index
|
/* If the component has varying offset, it behaves like index
|
as well. */
|
as well. */
|
idx = &TREE_OPERAND (*addr_p, 2);
|
idx = &TREE_OPERAND (*addr_p, 2);
|
if (*idx
|
if (*idx
|
&& !cbck (*addr_p, idx, data))
|
&& !cbck (*addr_p, idx, data))
|
return false;
|
return false;
|
|
|
nxt = &TREE_OPERAND (*addr_p, 0);
|
nxt = &TREE_OPERAND (*addr_p, 0);
|
break;
|
break;
|
|
|
case ARRAY_REF:
|
case ARRAY_REF:
|
case ARRAY_RANGE_REF:
|
case ARRAY_RANGE_REF:
|
nxt = &TREE_OPERAND (*addr_p, 0);
|
nxt = &TREE_OPERAND (*addr_p, 0);
|
if (!cbck (*addr_p, &TREE_OPERAND (*addr_p, 1), data))
|
if (!cbck (*addr_p, &TREE_OPERAND (*addr_p, 1), data))
|
return false;
|
return false;
|
break;
|
break;
|
|
|
case VAR_DECL:
|
case VAR_DECL:
|
case PARM_DECL:
|
case PARM_DECL:
|
case STRING_CST:
|
case STRING_CST:
|
case RESULT_DECL:
|
case RESULT_DECL:
|
case VECTOR_CST:
|
case VECTOR_CST:
|
case COMPLEX_CST:
|
case COMPLEX_CST:
|
case INTEGER_CST:
|
case INTEGER_CST:
|
case REAL_CST:
|
case REAL_CST:
|
return true;
|
return true;
|
|
|
case TARGET_MEM_REF:
|
case TARGET_MEM_REF:
|
idx = &TMR_BASE (*addr_p);
|
idx = &TMR_BASE (*addr_p);
|
if (*idx
|
if (*idx
|
&& !cbck (*addr_p, idx, data))
|
&& !cbck (*addr_p, idx, data))
|
return false;
|
return false;
|
idx = &TMR_INDEX (*addr_p);
|
idx = &TMR_INDEX (*addr_p);
|
if (*idx
|
if (*idx
|
&& !cbck (*addr_p, idx, data))
|
&& !cbck (*addr_p, idx, data))
|
return false;
|
return false;
|
return true;
|
return true;
|
|
|
default:
|
default:
|
gcc_unreachable ();
|
gcc_unreachable ();
|
}
|
}
|
}
|
}
|
}
|
}
|
|
|
/* If it is possible to hoist the statement STMT unconditionally,
|
/* If it is possible to hoist the statement STMT unconditionally,
|
returns MOVE_POSSIBLE.
|
returns MOVE_POSSIBLE.
|
If it is possible to hoist the statement STMT, but we must avoid making
|
If it is possible to hoist the statement STMT, but we must avoid making
|
it executed if it would not be executed in the original program (e.g.
|
it executed if it would not be executed in the original program (e.g.
|
because it may trap), return MOVE_PRESERVE_EXECUTION.
|
because it may trap), return MOVE_PRESERVE_EXECUTION.
|
Otherwise return MOVE_IMPOSSIBLE. */
|
Otherwise return MOVE_IMPOSSIBLE. */
|
|
|
enum move_pos
|
enum move_pos
|
movement_possibility (tree stmt)
|
movement_possibility (tree stmt)
|
{
|
{
|
tree lhs, rhs;
|
tree lhs, rhs;
|
|
|
if (flag_unswitch_loops
|
if (flag_unswitch_loops
|
&& TREE_CODE (stmt) == COND_EXPR)
|
&& TREE_CODE (stmt) == COND_EXPR)
|
{
|
{
|
/* If we perform unswitching, force the operands of the invariant
|
/* If we perform unswitching, force the operands of the invariant
|
condition to be moved out of the loop. */
|
condition to be moved out of the loop. */
|
return MOVE_POSSIBLE;
|
return MOVE_POSSIBLE;
|
}
|
}
|
|
|
if (TREE_CODE (stmt) != MODIFY_EXPR)
|
if (TREE_CODE (stmt) != MODIFY_EXPR)
|
return MOVE_IMPOSSIBLE;
|
return MOVE_IMPOSSIBLE;
|
|
|
if (stmt_ends_bb_p (stmt))
|
if (stmt_ends_bb_p (stmt))
|
return MOVE_IMPOSSIBLE;
|
return MOVE_IMPOSSIBLE;
|
|
|
if (stmt_ann (stmt)->has_volatile_ops)
|
if (stmt_ann (stmt)->has_volatile_ops)
|
return MOVE_IMPOSSIBLE;
|
return MOVE_IMPOSSIBLE;
|
|
|
lhs = TREE_OPERAND (stmt, 0);
|
lhs = TREE_OPERAND (stmt, 0);
|
if (TREE_CODE (lhs) == SSA_NAME
|
if (TREE_CODE (lhs) == SSA_NAME
|
&& SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs))
|
&& SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs))
|
return MOVE_IMPOSSIBLE;
|
return MOVE_IMPOSSIBLE;
|
|
|
rhs = TREE_OPERAND (stmt, 1);
|
rhs = TREE_OPERAND (stmt, 1);
|
|
|
if (TREE_SIDE_EFFECTS (rhs))
|
if (TREE_SIDE_EFFECTS (rhs))
|
return MOVE_IMPOSSIBLE;
|
return MOVE_IMPOSSIBLE;
|
|
|
if (TREE_CODE (lhs) != SSA_NAME
|
if (TREE_CODE (lhs) != SSA_NAME
|
|| tree_could_trap_p (rhs))
|
|| tree_could_trap_p (rhs))
|
return MOVE_PRESERVE_EXECUTION;
|
return MOVE_PRESERVE_EXECUTION;
|
|
|
if (get_call_expr_in (stmt))
|
if (get_call_expr_in (stmt))
|
{
|
{
|
/* While pure or const call is guaranteed to have no side effects, we
|
/* While pure or const call is guaranteed to have no side effects, we
|
cannot move it arbitrarily. Consider code like
|
cannot move it arbitrarily. Consider code like
|
|
|
char *s = something ();
|
char *s = something ();
|
|
|
while (1)
|
while (1)
|
{
|
{
|
if (s)
|
if (s)
|
t = strlen (s);
|
t = strlen (s);
|
else
|
else
|
t = 0;
|
t = 0;
|
}
|
}
|
|
|
Here the strlen call cannot be moved out of the loop, even though
|
Here the strlen call cannot be moved out of the loop, even though
|
s is invariant. In addition to possibly creating a call with
|
s is invariant. In addition to possibly creating a call with
|
invalid arguments, moving out a function call that is not executed
|
invalid arguments, moving out a function call that is not executed
|
may cause performance regressions in case the call is costly and
|
may cause performance regressions in case the call is costly and
|
not executed at all. */
|
not executed at all. */
|
return MOVE_PRESERVE_EXECUTION;
|
return MOVE_PRESERVE_EXECUTION;
|
}
|
}
|
return MOVE_POSSIBLE;
|
return MOVE_POSSIBLE;
|
}
|
}
|
|
|
/* Suppose that operand DEF is used inside the LOOP. Returns the outermost
|
/* Suppose that operand DEF is used inside the LOOP. Returns the outermost
|
loop to that we could move the expression using DEF if it did not have
|
loop to that we could move the expression using DEF if it did not have
|
other operands, i.e. the outermost loop enclosing LOOP in that the value
|
other operands, i.e. the outermost loop enclosing LOOP in that the value
|
of DEF is invariant. */
|
of DEF is invariant. */
|
|
|
static struct loop *
|
static struct loop *
|
outermost_invariant_loop (tree def, struct loop *loop)
|
outermost_invariant_loop (tree def, struct loop *loop)
|
{
|
{
|
tree def_stmt;
|
tree def_stmt;
|
basic_block def_bb;
|
basic_block def_bb;
|
struct loop *max_loop;
|
struct loop *max_loop;
|
|
|
if (TREE_CODE (def) != SSA_NAME)
|
if (TREE_CODE (def) != SSA_NAME)
|
return superloop_at_depth (loop, 1);
|
return superloop_at_depth (loop, 1);
|
|
|
def_stmt = SSA_NAME_DEF_STMT (def);
|
def_stmt = SSA_NAME_DEF_STMT (def);
|
def_bb = bb_for_stmt (def_stmt);
|
def_bb = bb_for_stmt (def_stmt);
|
if (!def_bb)
|
if (!def_bb)
|
return superloop_at_depth (loop, 1);
|
return superloop_at_depth (loop, 1);
|
|
|
max_loop = find_common_loop (loop, def_bb->loop_father);
|
max_loop = find_common_loop (loop, def_bb->loop_father);
|
|
|
if (LIM_DATA (def_stmt) && LIM_DATA (def_stmt)->max_loop)
|
if (LIM_DATA (def_stmt) && LIM_DATA (def_stmt)->max_loop)
|
max_loop = find_common_loop (max_loop,
|
max_loop = find_common_loop (max_loop,
|
LIM_DATA (def_stmt)->max_loop->outer);
|
LIM_DATA (def_stmt)->max_loop->outer);
|
if (max_loop == loop)
|
if (max_loop == loop)
|
return NULL;
|
return NULL;
|
max_loop = superloop_at_depth (loop, max_loop->depth + 1);
|
max_loop = superloop_at_depth (loop, max_loop->depth + 1);
|
|
|
return max_loop;
|
return max_loop;
|
}
|
}
|
|
|
/* Returns the outermost superloop of LOOP in that the expression EXPR is
|
/* Returns the outermost superloop of LOOP in that the expression EXPR is
|
invariant. */
|
invariant. */
|
|
|
static struct loop *
|
static struct loop *
|
outermost_invariant_loop_expr (tree expr, struct loop *loop)
|
outermost_invariant_loop_expr (tree expr, struct loop *loop)
|
{
|
{
|
enum tree_code_class class = TREE_CODE_CLASS (TREE_CODE (expr));
|
enum tree_code_class class = TREE_CODE_CLASS (TREE_CODE (expr));
|
unsigned i, nops;
|
unsigned i, nops;
|
struct loop *max_loop = superloop_at_depth (loop, 1), *aloop;
|
struct loop *max_loop = superloop_at_depth (loop, 1), *aloop;
|
|
|
if (TREE_CODE (expr) == SSA_NAME
|
if (TREE_CODE (expr) == SSA_NAME
|
|| TREE_CODE (expr) == INTEGER_CST
|
|| TREE_CODE (expr) == INTEGER_CST
|
|| is_gimple_min_invariant (expr))
|
|| is_gimple_min_invariant (expr))
|
return outermost_invariant_loop (expr, loop);
|
return outermost_invariant_loop (expr, loop);
|
|
|
if (class != tcc_unary
|
if (class != tcc_unary
|
&& class != tcc_binary
|
&& class != tcc_binary
|
&& class != tcc_expression
|
&& class != tcc_expression
|
&& class != tcc_comparison)
|
&& class != tcc_comparison)
|
return NULL;
|
return NULL;
|
|
|
nops = TREE_CODE_LENGTH (TREE_CODE (expr));
|
nops = TREE_CODE_LENGTH (TREE_CODE (expr));
|
for (i = 0; i < nops; i++)
|
for (i = 0; i < nops; i++)
|
{
|
{
|
aloop = outermost_invariant_loop_expr (TREE_OPERAND (expr, i), loop);
|
aloop = outermost_invariant_loop_expr (TREE_OPERAND (expr, i), loop);
|
if (!aloop)
|
if (!aloop)
|
return NULL;
|
return NULL;
|
|
|
if (flow_loop_nested_p (max_loop, aloop))
|
if (flow_loop_nested_p (max_loop, aloop))
|
max_loop = aloop;
|
max_loop = aloop;
|
}
|
}
|
|
|
return max_loop;
|
return max_loop;
|
}
|
}
|
|
|
/* DATA is a structure containing information associated with a statement
|
/* DATA is a structure containing information associated with a statement
|
inside LOOP. DEF is one of the operands of this statement.
|
inside LOOP. DEF is one of the operands of this statement.
|
|
|
Find the outermost loop enclosing LOOP in that value of DEF is invariant
|
Find the outermost loop enclosing LOOP in that value of DEF is invariant
|
and record this in DATA->max_loop field. If DEF itself is defined inside
|
and record this in DATA->max_loop field. If DEF itself is defined inside
|
this loop as well (i.e. we need to hoist it out of the loop if we want
|
this loop as well (i.e. we need to hoist it out of the loop if we want
|
to hoist the statement represented by DATA), record the statement in that
|
to hoist the statement represented by DATA), record the statement in that
|
DEF is defined to the DATA->depends list. Additionally if ADD_COST is true,
|
DEF is defined to the DATA->depends list. Additionally if ADD_COST is true,
|
add the cost of the computation of DEF to the DATA->cost.
|
add the cost of the computation of DEF to the DATA->cost.
|
|
|
If DEF is not invariant in LOOP, return false. Otherwise return TRUE. */
|
If DEF is not invariant in LOOP, return false. Otherwise return TRUE. */
|
|
|
static bool
|
static bool
|
add_dependency (tree def, struct lim_aux_data *data, struct loop *loop,
|
add_dependency (tree def, struct lim_aux_data *data, struct loop *loop,
|
bool add_cost)
|
bool add_cost)
|
{
|
{
|
tree def_stmt = SSA_NAME_DEF_STMT (def);
|
tree def_stmt = SSA_NAME_DEF_STMT (def);
|
basic_block def_bb = bb_for_stmt (def_stmt);
|
basic_block def_bb = bb_for_stmt (def_stmt);
|
struct loop *max_loop;
|
struct loop *max_loop;
|
struct depend *dep;
|
struct depend *dep;
|
|
|
if (!def_bb)
|
if (!def_bb)
|
return true;
|
return true;
|
|
|
max_loop = outermost_invariant_loop (def, loop);
|
max_loop = outermost_invariant_loop (def, loop);
|
if (!max_loop)
|
if (!max_loop)
|
return false;
|
return false;
|
|
|
if (flow_loop_nested_p (data->max_loop, max_loop))
|
if (flow_loop_nested_p (data->max_loop, max_loop))
|
data->max_loop = max_loop;
|
data->max_loop = max_loop;
|
|
|
if (!LIM_DATA (def_stmt))
|
if (!LIM_DATA (def_stmt))
|
return true;
|
return true;
|
|
|
if (add_cost
|
if (add_cost
|
/* Only add the cost if the statement defining DEF is inside LOOP,
|
/* Only add the cost if the statement defining DEF is inside LOOP,
|
i.e. if it is likely that by moving the invariants dependent
|
i.e. if it is likely that by moving the invariants dependent
|
on it, we will be able to avoid creating a new register for
|
on it, we will be able to avoid creating a new register for
|
it (since it will be only used in these dependent invariants). */
|
it (since it will be only used in these dependent invariants). */
|
&& def_bb->loop_father == loop)
|
&& def_bb->loop_father == loop)
|
data->cost += LIM_DATA (def_stmt)->cost;
|
data->cost += LIM_DATA (def_stmt)->cost;
|
|
|
dep = XNEW (struct depend);
|
dep = XNEW (struct depend);
|
dep->stmt = def_stmt;
|
dep->stmt = def_stmt;
|
dep->next = data->depends;
|
dep->next = data->depends;
|
data->depends = dep;
|
data->depends = dep;
|
|
|
return true;
|
return true;
|
}
|
}
|
|
|
/* Returns an estimate for a cost of statement STMT. TODO -- the values here
|
/* Returns an estimate for a cost of statement STMT. TODO -- the values here
|
are just ad-hoc constants. The estimates should be based on target-specific
|
are just ad-hoc constants. The estimates should be based on target-specific
|
values. */
|
values. */
|
|
|
static unsigned
|
static unsigned
|
stmt_cost (tree stmt)
|
stmt_cost (tree stmt)
|
{
|
{
|
tree rhs;
|
tree rhs;
|
unsigned cost = 1;
|
unsigned cost = 1;
|
|
|
/* Always try to create possibilities for unswitching. */
|
/* Always try to create possibilities for unswitching. */
|
if (TREE_CODE (stmt) == COND_EXPR)
|
if (TREE_CODE (stmt) == COND_EXPR)
|
return LIM_EXPENSIVE;
|
return LIM_EXPENSIVE;
|
|
|
rhs = TREE_OPERAND (stmt, 1);
|
rhs = TREE_OPERAND (stmt, 1);
|
|
|
/* Hoisting memory references out should almost surely be a win. */
|
/* Hoisting memory references out should almost surely be a win. */
|
if (stmt_references_memory_p (stmt))
|
if (stmt_references_memory_p (stmt))
|
cost += 20;
|
cost += 20;
|
|
|
switch (TREE_CODE (rhs))
|
switch (TREE_CODE (rhs))
|
{
|
{
|
case CALL_EXPR:
|
case CALL_EXPR:
|
/* We should be hoisting calls if possible. */
|
/* We should be hoisting calls if possible. */
|
|
|
/* Unless the call is a builtin_constant_p; this always folds to a
|
/* Unless the call is a builtin_constant_p; this always folds to a
|
constant, so moving it is useless. */
|
constant, so moving it is useless. */
|
rhs = get_callee_fndecl (rhs);
|
rhs = get_callee_fndecl (rhs);
|
if (DECL_BUILT_IN_CLASS (rhs) == BUILT_IN_NORMAL
|
if (DECL_BUILT_IN_CLASS (rhs) == BUILT_IN_NORMAL
|
&& DECL_FUNCTION_CODE (rhs) == BUILT_IN_CONSTANT_P)
|
&& DECL_FUNCTION_CODE (rhs) == BUILT_IN_CONSTANT_P)
|
return 0;
|
return 0;
|
|
|
cost += 20;
|
cost += 20;
|
break;
|
break;
|
|
|
case MULT_EXPR:
|
case MULT_EXPR:
|
case TRUNC_DIV_EXPR:
|
case TRUNC_DIV_EXPR:
|
case CEIL_DIV_EXPR:
|
case CEIL_DIV_EXPR:
|
case FLOOR_DIV_EXPR:
|
case FLOOR_DIV_EXPR:
|
case ROUND_DIV_EXPR:
|
case ROUND_DIV_EXPR:
|
case EXACT_DIV_EXPR:
|
case EXACT_DIV_EXPR:
|
case CEIL_MOD_EXPR:
|
case CEIL_MOD_EXPR:
|
case FLOOR_MOD_EXPR:
|
case FLOOR_MOD_EXPR:
|
case ROUND_MOD_EXPR:
|
case ROUND_MOD_EXPR:
|
case TRUNC_MOD_EXPR:
|
case TRUNC_MOD_EXPR:
|
case RDIV_EXPR:
|
case RDIV_EXPR:
|
/* Division and multiplication are usually expensive. */
|
/* Division and multiplication are usually expensive. */
|
cost += 20;
|
cost += 20;
|
break;
|
break;
|
|
|
default:
|
default:
|
break;
|
break;
|
}
|
}
|
|
|
return cost;
|
return cost;
|
}
|
}
|
|
|
/* Determine the outermost loop to that it is possible to hoist a statement
|
/* Determine the outermost loop to that it is possible to hoist a statement
|
STMT and store it to LIM_DATA (STMT)->max_loop. To do this we determine
|
STMT and store it to LIM_DATA (STMT)->max_loop. To do this we determine
|
the outermost loop in that the value computed by STMT is invariant.
|
the outermost loop in that the value computed by STMT is invariant.
|
If MUST_PRESERVE_EXEC is true, additionally choose such a loop that
|
If MUST_PRESERVE_EXEC is true, additionally choose such a loop that
|
we preserve the fact whether STMT is executed. It also fills other related
|
we preserve the fact whether STMT is executed. It also fills other related
|
information to LIM_DATA (STMT).
|
information to LIM_DATA (STMT).
|
|
|
The function returns false if STMT cannot be hoisted outside of the loop it
|
The function returns false if STMT cannot be hoisted outside of the loop it
|
is defined in, and true otherwise. */
|
is defined in, and true otherwise. */
|
|
|
static bool
|
static bool
|
determine_max_movement (tree stmt, bool must_preserve_exec)
|
determine_max_movement (tree stmt, bool must_preserve_exec)
|
{
|
{
|
basic_block bb = bb_for_stmt (stmt);
|
basic_block bb = bb_for_stmt (stmt);
|
struct loop *loop = bb->loop_father;
|
struct loop *loop = bb->loop_father;
|
struct loop *level;
|
struct loop *level;
|
struct lim_aux_data *lim_data = LIM_DATA (stmt);
|
struct lim_aux_data *lim_data = LIM_DATA (stmt);
|
tree val;
|
tree val;
|
ssa_op_iter iter;
|
ssa_op_iter iter;
|
|
|
if (must_preserve_exec)
|
if (must_preserve_exec)
|
level = ALWAYS_EXECUTED_IN (bb);
|
level = ALWAYS_EXECUTED_IN (bb);
|
else
|
else
|
level = superloop_at_depth (loop, 1);
|
level = superloop_at_depth (loop, 1);
|
lim_data->max_loop = level;
|
lim_data->max_loop = level;
|
|
|
FOR_EACH_SSA_TREE_OPERAND (val, stmt, iter, SSA_OP_USE)
|
FOR_EACH_SSA_TREE_OPERAND (val, stmt, iter, SSA_OP_USE)
|
if (!add_dependency (val, lim_data, loop, true))
|
if (!add_dependency (val, lim_data, loop, true))
|
return false;
|
return false;
|
|
|
FOR_EACH_SSA_TREE_OPERAND (val, stmt, iter, SSA_OP_VIRTUAL_USES | SSA_OP_VIRTUAL_KILLS)
|
FOR_EACH_SSA_TREE_OPERAND (val, stmt, iter, SSA_OP_VIRTUAL_USES | SSA_OP_VIRTUAL_KILLS)
|
if (!add_dependency (val, lim_data, loop, false))
|
if (!add_dependency (val, lim_data, loop, false))
|
return false;
|
return false;
|
|
|
lim_data->cost += stmt_cost (stmt);
|
lim_data->cost += stmt_cost (stmt);
|
|
|
return true;
|
return true;
|
}
|
}
|
|
|
/* Suppose that some statement in ORIG_LOOP is hoisted to the loop LEVEL,
|
/* Suppose that some statement in ORIG_LOOP is hoisted to the loop LEVEL,
|
and that one of the operands of this statement is computed by STMT.
|
and that one of the operands of this statement is computed by STMT.
|
Ensure that STMT (together with all the statements that define its
|
Ensure that STMT (together with all the statements that define its
|
operands) is hoisted at least out of the loop LEVEL. */
|
operands) is hoisted at least out of the loop LEVEL. */
|
|
|
static void
|
static void
|
set_level (tree stmt, struct loop *orig_loop, struct loop *level)
|
set_level (tree stmt, struct loop *orig_loop, struct loop *level)
|
{
|
{
|
struct loop *stmt_loop = bb_for_stmt (stmt)->loop_father;
|
struct loop *stmt_loop = bb_for_stmt (stmt)->loop_father;
|
struct depend *dep;
|
struct depend *dep;
|
|
|
stmt_loop = find_common_loop (orig_loop, stmt_loop);
|
stmt_loop = find_common_loop (orig_loop, stmt_loop);
|
if (LIM_DATA (stmt) && LIM_DATA (stmt)->tgt_loop)
|
if (LIM_DATA (stmt) && LIM_DATA (stmt)->tgt_loop)
|
stmt_loop = find_common_loop (stmt_loop,
|
stmt_loop = find_common_loop (stmt_loop,
|
LIM_DATA (stmt)->tgt_loop->outer);
|
LIM_DATA (stmt)->tgt_loop->outer);
|
if (flow_loop_nested_p (stmt_loop, level))
|
if (flow_loop_nested_p (stmt_loop, level))
|
return;
|
return;
|
|
|
gcc_assert (LIM_DATA (stmt));
|
gcc_assert (LIM_DATA (stmt));
|
gcc_assert (level == LIM_DATA (stmt)->max_loop
|
gcc_assert (level == LIM_DATA (stmt)->max_loop
|
|| flow_loop_nested_p (LIM_DATA (stmt)->max_loop, level));
|
|| flow_loop_nested_p (LIM_DATA (stmt)->max_loop, level));
|
|
|
LIM_DATA (stmt)->tgt_loop = level;
|
LIM_DATA (stmt)->tgt_loop = level;
|
for (dep = LIM_DATA (stmt)->depends; dep; dep = dep->next)
|
for (dep = LIM_DATA (stmt)->depends; dep; dep = dep->next)
|
set_level (dep->stmt, orig_loop, level);
|
set_level (dep->stmt, orig_loop, level);
|
}
|
}
|
|
|
/* Determines an outermost loop from that we want to hoist the statement STMT.
|
/* Determines an outermost loop from that we want to hoist the statement STMT.
|
For now we chose the outermost possible loop. TODO -- use profiling
|
For now we chose the outermost possible loop. TODO -- use profiling
|
information to set it more sanely. */
|
information to set it more sanely. */
|
|
|
static void
|
static void
|
set_profitable_level (tree stmt)
|
set_profitable_level (tree stmt)
|
{
|
{
|
set_level (stmt, bb_for_stmt (stmt)->loop_father, LIM_DATA (stmt)->max_loop);
|
set_level (stmt, bb_for_stmt (stmt)->loop_father, LIM_DATA (stmt)->max_loop);
|
}
|
}
|
|
|
/* Returns true if STMT is not a pure call. */
|
/* Returns true if STMT is not a pure call. */
|
|
|
static bool
|
static bool
|
nonpure_call_p (tree stmt)
|
nonpure_call_p (tree stmt)
|
{
|
{
|
tree call = get_call_expr_in (stmt);
|
tree call = get_call_expr_in (stmt);
|
|
|
if (!call)
|
if (!call)
|
return false;
|
return false;
|
|
|
return TREE_SIDE_EFFECTS (call) != 0;
|
return TREE_SIDE_EFFECTS (call) != 0;
|
}
|
}
|
|
|
/* Releases the memory occupied by DATA. */
|
/* Releases the memory occupied by DATA. */
|
|
|
static void
|
static void
|
free_lim_aux_data (struct lim_aux_data *data)
|
free_lim_aux_data (struct lim_aux_data *data)
|
{
|
{
|
struct depend *dep, *next;
|
struct depend *dep, *next;
|
|
|
for (dep = data->depends; dep; dep = next)
|
for (dep = data->depends; dep; dep = next)
|
{
|
{
|
next = dep->next;
|
next = dep->next;
|
free (dep);
|
free (dep);
|
}
|
}
|
free (data);
|
free (data);
|
}
|
}
|
|
|
/* Determine the outermost loops in that statements in basic block BB are
|
/* Determine the outermost loops in that statements in basic block BB are
|
invariant, and record them to the LIM_DATA associated with the statements.
|
invariant, and record them to the LIM_DATA associated with the statements.
|
Callback for walk_dominator_tree. */
|
Callback for walk_dominator_tree. */
|
|
|
static void
|
static void
|
determine_invariantness_stmt (struct dom_walk_data *dw_data ATTRIBUTE_UNUSED,
|
determine_invariantness_stmt (struct dom_walk_data *dw_data ATTRIBUTE_UNUSED,
|
basic_block bb)
|
basic_block bb)
|
{
|
{
|
enum move_pos pos;
|
enum move_pos pos;
|
block_stmt_iterator bsi;
|
block_stmt_iterator bsi;
|
tree stmt, rhs;
|
tree stmt, rhs;
|
bool maybe_never = ALWAYS_EXECUTED_IN (bb) == NULL;
|
bool maybe_never = ALWAYS_EXECUTED_IN (bb) == NULL;
|
struct loop *outermost = ALWAYS_EXECUTED_IN (bb);
|
struct loop *outermost = ALWAYS_EXECUTED_IN (bb);
|
|
|
if (!bb->loop_father->outer)
|
if (!bb->loop_father->outer)
|
return;
|
return;
|
|
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
fprintf (dump_file, "Basic block %d (loop %d -- depth %d):\n\n",
|
fprintf (dump_file, "Basic block %d (loop %d -- depth %d):\n\n",
|
bb->index, bb->loop_father->num, bb->loop_father->depth);
|
bb->index, bb->loop_father->num, bb->loop_father->depth);
|
|
|
for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
|
for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
|
{
|
{
|
stmt = bsi_stmt (bsi);
|
stmt = bsi_stmt (bsi);
|
|
|
pos = movement_possibility (stmt);
|
pos = movement_possibility (stmt);
|
if (pos == MOVE_IMPOSSIBLE)
|
if (pos == MOVE_IMPOSSIBLE)
|
{
|
{
|
if (nonpure_call_p (stmt))
|
if (nonpure_call_p (stmt))
|
{
|
{
|
maybe_never = true;
|
maybe_never = true;
|
outermost = NULL;
|
outermost = NULL;
|
}
|
}
|
continue;
|
continue;
|
}
|
}
|
|
|
/* If divisor is invariant, convert a/b to a*(1/b), allowing reciprocal
|
/* If divisor is invariant, convert a/b to a*(1/b), allowing reciprocal
|
to be hoisted out of loop, saving expensive divide. */
|
to be hoisted out of loop, saving expensive divide. */
|
if (pos == MOVE_POSSIBLE
|
if (pos == MOVE_POSSIBLE
|
&& (rhs = TREE_OPERAND (stmt, 1)) != NULL
|
&& (rhs = TREE_OPERAND (stmt, 1)) != NULL
|
&& TREE_CODE (rhs) == RDIV_EXPR
|
&& TREE_CODE (rhs) == RDIV_EXPR
|
&& flag_unsafe_math_optimizations
|
&& flag_unsafe_math_optimizations
|
&& !flag_trapping_math
|
&& !flag_trapping_math
|
&& outermost_invariant_loop_expr (TREE_OPERAND (rhs, 1),
|
&& outermost_invariant_loop_expr (TREE_OPERAND (rhs, 1),
|
loop_containing_stmt (stmt)) != NULL
|
loop_containing_stmt (stmt)) != NULL
|
&& outermost_invariant_loop_expr (rhs,
|
&& outermost_invariant_loop_expr (rhs,
|
loop_containing_stmt (stmt)) == NULL)
|
loop_containing_stmt (stmt)) == NULL)
|
{
|
{
|
tree lhs, stmt1, stmt2, var, name;
|
tree lhs, stmt1, stmt2, var, name;
|
|
|
lhs = TREE_OPERAND (stmt, 0);
|
lhs = TREE_OPERAND (stmt, 0);
|
|
|
/* stmt must be MODIFY_EXPR. */
|
/* stmt must be MODIFY_EXPR. */
|
var = create_tmp_var (TREE_TYPE (rhs), "reciptmp");
|
var = create_tmp_var (TREE_TYPE (rhs), "reciptmp");
|
add_referenced_var (var);
|
add_referenced_var (var);
|
|
|
stmt1 = build2 (MODIFY_EXPR, void_type_node, var,
|
stmt1 = build2 (MODIFY_EXPR, void_type_node, var,
|
build2 (RDIV_EXPR, TREE_TYPE (rhs),
|
build2 (RDIV_EXPR, TREE_TYPE (rhs),
|
build_real (TREE_TYPE (rhs), dconst1),
|
build_real (TREE_TYPE (rhs), dconst1),
|
TREE_OPERAND (rhs, 1)));
|
TREE_OPERAND (rhs, 1)));
|
name = make_ssa_name (var, stmt1);
|
name = make_ssa_name (var, stmt1);
|
TREE_OPERAND (stmt1, 0) = name;
|
TREE_OPERAND (stmt1, 0) = name;
|
stmt2 = build2 (MODIFY_EXPR, void_type_node, lhs,
|
stmt2 = build2 (MODIFY_EXPR, void_type_node, lhs,
|
build2 (MULT_EXPR, TREE_TYPE (rhs),
|
build2 (MULT_EXPR, TREE_TYPE (rhs),
|
name, TREE_OPERAND (rhs, 0)));
|
name, TREE_OPERAND (rhs, 0)));
|
|
|
/* Replace division stmt with reciprocal and multiply stmts.
|
/* Replace division stmt with reciprocal and multiply stmts.
|
The multiply stmt is not invariant, so update iterator
|
The multiply stmt is not invariant, so update iterator
|
and avoid rescanning. */
|
and avoid rescanning. */
|
bsi_replace (&bsi, stmt1, true);
|
bsi_replace (&bsi, stmt1, true);
|
bsi_insert_after (&bsi, stmt2, BSI_NEW_STMT);
|
bsi_insert_after (&bsi, stmt2, BSI_NEW_STMT);
|
SSA_NAME_DEF_STMT (lhs) = stmt2;
|
SSA_NAME_DEF_STMT (lhs) = stmt2;
|
|
|
/* Continue processing with invariant reciprocal statement. */
|
/* Continue processing with invariant reciprocal statement. */
|
stmt = stmt1;
|
stmt = stmt1;
|
}
|
}
|
|
|
stmt_ann (stmt)->common.aux = xcalloc (1, sizeof (struct lim_aux_data));
|
stmt_ann (stmt)->common.aux = xcalloc (1, sizeof (struct lim_aux_data));
|
LIM_DATA (stmt)->always_executed_in = outermost;
|
LIM_DATA (stmt)->always_executed_in = outermost;
|
|
|
if (maybe_never && pos == MOVE_PRESERVE_EXECUTION)
|
if (maybe_never && pos == MOVE_PRESERVE_EXECUTION)
|
continue;
|
continue;
|
|
|
if (!determine_max_movement (stmt, pos == MOVE_PRESERVE_EXECUTION))
|
if (!determine_max_movement (stmt, pos == MOVE_PRESERVE_EXECUTION))
|
{
|
{
|
LIM_DATA (stmt)->max_loop = NULL;
|
LIM_DATA (stmt)->max_loop = NULL;
|
continue;
|
continue;
|
}
|
}
|
|
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
{
|
{
|
print_generic_stmt_indented (dump_file, stmt, 0, 2);
|
print_generic_stmt_indented (dump_file, stmt, 0, 2);
|
fprintf (dump_file, " invariant up to level %d, cost %d.\n\n",
|
fprintf (dump_file, " invariant up to level %d, cost %d.\n\n",
|
LIM_DATA (stmt)->max_loop->depth,
|
LIM_DATA (stmt)->max_loop->depth,
|
LIM_DATA (stmt)->cost);
|
LIM_DATA (stmt)->cost);
|
}
|
}
|
|
|
if (LIM_DATA (stmt)->cost >= LIM_EXPENSIVE)
|
if (LIM_DATA (stmt)->cost >= LIM_EXPENSIVE)
|
set_profitable_level (stmt);
|
set_profitable_level (stmt);
|
}
|
}
|
}
|
}
|
|
|
/* For each statement determines the outermost loop in that it is invariant,
|
/* For each statement determines the outermost loop in that it is invariant,
|
statements on whose motion it depends and the cost of the computation.
|
statements on whose motion it depends and the cost of the computation.
|
This information is stored to the LIM_DATA structure associated with
|
This information is stored to the LIM_DATA structure associated with
|
each statement. */
|
each statement. */
|
|
|
static void
|
static void
|
determine_invariantness (void)
|
determine_invariantness (void)
|
{
|
{
|
struct dom_walk_data walk_data;
|
struct dom_walk_data walk_data;
|
|
|
memset (&walk_data, 0, sizeof (struct dom_walk_data));
|
memset (&walk_data, 0, sizeof (struct dom_walk_data));
|
walk_data.before_dom_children_before_stmts = determine_invariantness_stmt;
|
walk_data.before_dom_children_before_stmts = determine_invariantness_stmt;
|
|
|
init_walk_dominator_tree (&walk_data);
|
init_walk_dominator_tree (&walk_data);
|
walk_dominator_tree (&walk_data, ENTRY_BLOCK_PTR);
|
walk_dominator_tree (&walk_data, ENTRY_BLOCK_PTR);
|
fini_walk_dominator_tree (&walk_data);
|
fini_walk_dominator_tree (&walk_data);
|
}
|
}
|
|
|
/* Commits edge insertions and updates loop structures. */
|
/* Commits edge insertions and updates loop structures. */
|
|
|
void
|
void
|
loop_commit_inserts (void)
|
loop_commit_inserts (void)
|
{
|
{
|
unsigned old_last_basic_block, i;
|
unsigned old_last_basic_block, i;
|
basic_block bb;
|
basic_block bb;
|
|
|
old_last_basic_block = last_basic_block;
|
old_last_basic_block = last_basic_block;
|
bsi_commit_edge_inserts ();
|
bsi_commit_edge_inserts ();
|
for (i = old_last_basic_block; i < (unsigned) last_basic_block; i++)
|
for (i = old_last_basic_block; i < (unsigned) last_basic_block; i++)
|
{
|
{
|
bb = BASIC_BLOCK (i);
|
bb = BASIC_BLOCK (i);
|
add_bb_to_loop (bb,
|
add_bb_to_loop (bb,
|
find_common_loop (single_pred (bb)->loop_father,
|
find_common_loop (single_pred (bb)->loop_father,
|
single_succ (bb)->loop_father));
|
single_succ (bb)->loop_father));
|
}
|
}
|
}
|
}
|
|
|
/* Hoist the statements in basic block BB out of the loops prescribed by
|
/* Hoist the statements in basic block BB out of the loops prescribed by
|
data stored in LIM_DATA structures associated with each statement. Callback
|
data stored in LIM_DATA structures associated with each statement. Callback
|
for walk_dominator_tree. */
|
for walk_dominator_tree. */
|
|
|
static void
|
static void
|
move_computations_stmt (struct dom_walk_data *dw_data ATTRIBUTE_UNUSED,
|
move_computations_stmt (struct dom_walk_data *dw_data ATTRIBUTE_UNUSED,
|
basic_block bb)
|
basic_block bb)
|
{
|
{
|
struct loop *level;
|
struct loop *level;
|
block_stmt_iterator bsi;
|
block_stmt_iterator bsi;
|
tree stmt;
|
tree stmt;
|
unsigned cost = 0;
|
unsigned cost = 0;
|
|
|
if (!bb->loop_father->outer)
|
if (!bb->loop_father->outer)
|
return;
|
return;
|
|
|
for (bsi = bsi_start (bb); !bsi_end_p (bsi); )
|
for (bsi = bsi_start (bb); !bsi_end_p (bsi); )
|
{
|
{
|
stmt = bsi_stmt (bsi);
|
stmt = bsi_stmt (bsi);
|
|
|
if (!LIM_DATA (stmt))
|
if (!LIM_DATA (stmt))
|
{
|
{
|
bsi_next (&bsi);
|
bsi_next (&bsi);
|
continue;
|
continue;
|
}
|
}
|
|
|
cost = LIM_DATA (stmt)->cost;
|
cost = LIM_DATA (stmt)->cost;
|
level = LIM_DATA (stmt)->tgt_loop;
|
level = LIM_DATA (stmt)->tgt_loop;
|
free_lim_aux_data (LIM_DATA (stmt));
|
free_lim_aux_data (LIM_DATA (stmt));
|
stmt_ann (stmt)->common.aux = NULL;
|
stmt_ann (stmt)->common.aux = NULL;
|
|
|
if (!level)
|
if (!level)
|
{
|
{
|
bsi_next (&bsi);
|
bsi_next (&bsi);
|
continue;
|
continue;
|
}
|
}
|
|
|
/* We do not really want to move conditionals out of the loop; we just
|
/* We do not really want to move conditionals out of the loop; we just
|
placed it here to force its operands to be moved if necessary. */
|
placed it here to force its operands to be moved if necessary. */
|
if (TREE_CODE (stmt) == COND_EXPR)
|
if (TREE_CODE (stmt) == COND_EXPR)
|
continue;
|
continue;
|
|
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
{
|
{
|
fprintf (dump_file, "Moving statement\n");
|
fprintf (dump_file, "Moving statement\n");
|
print_generic_stmt (dump_file, stmt, 0);
|
print_generic_stmt (dump_file, stmt, 0);
|
fprintf (dump_file, "(cost %u) out of loop %d.\n\n",
|
fprintf (dump_file, "(cost %u) out of loop %d.\n\n",
|
cost, level->num);
|
cost, level->num);
|
}
|
}
|
bsi_insert_on_edge (loop_preheader_edge (level), stmt);
|
bsi_insert_on_edge (loop_preheader_edge (level), stmt);
|
bsi_remove (&bsi, false);
|
bsi_remove (&bsi, false);
|
}
|
}
|
}
|
}
|
|
|
/* Hoist the statements out of the loops prescribed by data stored in
|
/* Hoist the statements out of the loops prescribed by data stored in
|
LIM_DATA structures associated with each statement.*/
|
LIM_DATA structures associated with each statement.*/
|
|
|
static void
|
static void
|
move_computations (void)
|
move_computations (void)
|
{
|
{
|
struct dom_walk_data walk_data;
|
struct dom_walk_data walk_data;
|
|
|
memset (&walk_data, 0, sizeof (struct dom_walk_data));
|
memset (&walk_data, 0, sizeof (struct dom_walk_data));
|
walk_data.before_dom_children_before_stmts = move_computations_stmt;
|
walk_data.before_dom_children_before_stmts = move_computations_stmt;
|
|
|
init_walk_dominator_tree (&walk_data);
|
init_walk_dominator_tree (&walk_data);
|
walk_dominator_tree (&walk_data, ENTRY_BLOCK_PTR);
|
walk_dominator_tree (&walk_data, ENTRY_BLOCK_PTR);
|
fini_walk_dominator_tree (&walk_data);
|
fini_walk_dominator_tree (&walk_data);
|
|
|
loop_commit_inserts ();
|
loop_commit_inserts ();
|
if (need_ssa_update_p ())
|
if (need_ssa_update_p ())
|
rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa);
|
rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa);
|
}
|
}
|
|
|
/* Checks whether the statement defining variable *INDEX can be hoisted
|
/* Checks whether the statement defining variable *INDEX can be hoisted
|
out of the loop passed in DATA. Callback for for_each_index. */
|
out of the loop passed in DATA. Callback for for_each_index. */
|
|
|
static bool
|
static bool
|
may_move_till (tree ref, tree *index, void *data)
|
may_move_till (tree ref, tree *index, void *data)
|
{
|
{
|
struct loop *loop = data, *max_loop;
|
struct loop *loop = data, *max_loop;
|
|
|
/* If REF is an array reference, check also that the step and the lower
|
/* If REF is an array reference, check also that the step and the lower
|
bound is invariant in LOOP. */
|
bound is invariant in LOOP. */
|
if (TREE_CODE (ref) == ARRAY_REF)
|
if (TREE_CODE (ref) == ARRAY_REF)
|
{
|
{
|
tree step = array_ref_element_size (ref);
|
tree step = array_ref_element_size (ref);
|
tree lbound = array_ref_low_bound (ref);
|
tree lbound = array_ref_low_bound (ref);
|
|
|
max_loop = outermost_invariant_loop_expr (step, loop);
|
max_loop = outermost_invariant_loop_expr (step, loop);
|
if (!max_loop)
|
if (!max_loop)
|
return false;
|
return false;
|
|
|
max_loop = outermost_invariant_loop_expr (lbound, loop);
|
max_loop = outermost_invariant_loop_expr (lbound, loop);
|
if (!max_loop)
|
if (!max_loop)
|
return false;
|
return false;
|
}
|
}
|
|
|
max_loop = outermost_invariant_loop (*index, loop);
|
max_loop = outermost_invariant_loop (*index, loop);
|
if (!max_loop)
|
if (!max_loop)
|
return false;
|
return false;
|
|
|
return true;
|
return true;
|
}
|
}
|
|
|
/* Forces statements defining (invariant) SSA names in expression EXPR to be
|
/* Forces statements defining (invariant) SSA names in expression EXPR to be
|
moved out of the LOOP. ORIG_LOOP is the loop in that EXPR is used. */
|
moved out of the LOOP. ORIG_LOOP is the loop in that EXPR is used. */
|
|
|
static void
|
static void
|
force_move_till_expr (tree expr, struct loop *orig_loop, struct loop *loop)
|
force_move_till_expr (tree expr, struct loop *orig_loop, struct loop *loop)
|
{
|
{
|
enum tree_code_class class = TREE_CODE_CLASS (TREE_CODE (expr));
|
enum tree_code_class class = TREE_CODE_CLASS (TREE_CODE (expr));
|
unsigned i, nops;
|
unsigned i, nops;
|
|
|
if (TREE_CODE (expr) == SSA_NAME)
|
if (TREE_CODE (expr) == SSA_NAME)
|
{
|
{
|
tree stmt = SSA_NAME_DEF_STMT (expr);
|
tree stmt = SSA_NAME_DEF_STMT (expr);
|
if (IS_EMPTY_STMT (stmt))
|
if (IS_EMPTY_STMT (stmt))
|
return;
|
return;
|
|
|
set_level (stmt, orig_loop, loop);
|
set_level (stmt, orig_loop, loop);
|
return;
|
return;
|
}
|
}
|
|
|
if (class != tcc_unary
|
if (class != tcc_unary
|
&& class != tcc_binary
|
&& class != tcc_binary
|
&& class != tcc_expression
|
&& class != tcc_expression
|
&& class != tcc_comparison)
|
&& class != tcc_comparison)
|
return;
|
return;
|
|
|
nops = TREE_CODE_LENGTH (TREE_CODE (expr));
|
nops = TREE_CODE_LENGTH (TREE_CODE (expr));
|
for (i = 0; i < nops; i++)
|
for (i = 0; i < nops; i++)
|
force_move_till_expr (TREE_OPERAND (expr, i), orig_loop, loop);
|
force_move_till_expr (TREE_OPERAND (expr, i), orig_loop, loop);
|
}
|
}
|
|
|
/* Forces statement defining invariants in REF (and *INDEX) to be moved out of
|
/* Forces statement defining invariants in REF (and *INDEX) to be moved out of
|
the LOOP. The reference REF is used in the loop ORIG_LOOP. Callback for
|
the LOOP. The reference REF is used in the loop ORIG_LOOP. Callback for
|
for_each_index. */
|
for_each_index. */
|
|
|
struct fmt_data
|
struct fmt_data
|
{
|
{
|
struct loop *loop;
|
struct loop *loop;
|
struct loop *orig_loop;
|
struct loop *orig_loop;
|
};
|
};
|
|
|
static bool
|
static bool
|
force_move_till (tree ref, tree *index, void *data)
|
force_move_till (tree ref, tree *index, void *data)
|
{
|
{
|
tree stmt;
|
tree stmt;
|
struct fmt_data *fmt_data = data;
|
struct fmt_data *fmt_data = data;
|
|
|
if (TREE_CODE (ref) == ARRAY_REF)
|
if (TREE_CODE (ref) == ARRAY_REF)
|
{
|
{
|
tree step = array_ref_element_size (ref);
|
tree step = array_ref_element_size (ref);
|
tree lbound = array_ref_low_bound (ref);
|
tree lbound = array_ref_low_bound (ref);
|
|
|
force_move_till_expr (step, fmt_data->orig_loop, fmt_data->loop);
|
force_move_till_expr (step, fmt_data->orig_loop, fmt_data->loop);
|
force_move_till_expr (lbound, fmt_data->orig_loop, fmt_data->loop);
|
force_move_till_expr (lbound, fmt_data->orig_loop, fmt_data->loop);
|
}
|
}
|
|
|
if (TREE_CODE (*index) != SSA_NAME)
|
if (TREE_CODE (*index) != SSA_NAME)
|
return true;
|
return true;
|
|
|
stmt = SSA_NAME_DEF_STMT (*index);
|
stmt = SSA_NAME_DEF_STMT (*index);
|
if (IS_EMPTY_STMT (stmt))
|
if (IS_EMPTY_STMT (stmt))
|
return true;
|
return true;
|
|
|
set_level (stmt, fmt_data->orig_loop, fmt_data->loop);
|
set_level (stmt, fmt_data->orig_loop, fmt_data->loop);
|
|
|
return true;
|
return true;
|
}
|
}
|
|
|
/* Records memory reference location *REF to the list MEM_REFS. The reference
|
/* Records memory reference location *REF to the list MEM_REFS. The reference
|
occurs in statement STMT. */
|
occurs in statement STMT. */
|
|
|
static void
|
static void
|
record_mem_ref_loc (struct mem_ref_loc **mem_refs, tree stmt, tree *ref)
|
record_mem_ref_loc (struct mem_ref_loc **mem_refs, tree stmt, tree *ref)
|
{
|
{
|
struct mem_ref_loc *aref = XNEW (struct mem_ref_loc);
|
struct mem_ref_loc *aref = XNEW (struct mem_ref_loc);
|
|
|
aref->stmt = stmt;
|
aref->stmt = stmt;
|
aref->ref = ref;
|
aref->ref = ref;
|
|
|
aref->next = *mem_refs;
|
aref->next = *mem_refs;
|
*mem_refs = aref;
|
*mem_refs = aref;
|
}
|
}
|
|
|
/* Releases list of memory reference locations MEM_REFS. */
|
/* Releases list of memory reference locations MEM_REFS. */
|
|
|
static void
|
static void
|
free_mem_ref_locs (struct mem_ref_loc *mem_refs)
|
free_mem_ref_locs (struct mem_ref_loc *mem_refs)
|
{
|
{
|
struct mem_ref_loc *act;
|
struct mem_ref_loc *act;
|
|
|
while (mem_refs)
|
while (mem_refs)
|
{
|
{
|
act = mem_refs;
|
act = mem_refs;
|
mem_refs = mem_refs->next;
|
mem_refs = mem_refs->next;
|
free (act);
|
free (act);
|
}
|
}
|
}
|
}
|
|
|
/* Rewrites memory references in list MEM_REFS by variable TMP_VAR. */
|
/* Rewrites memory references in list MEM_REFS by variable TMP_VAR. */
|
|
|
static void
|
static void
|
rewrite_mem_refs (tree tmp_var, struct mem_ref_loc *mem_refs)
|
rewrite_mem_refs (tree tmp_var, struct mem_ref_loc *mem_refs)
|
{
|
{
|
tree var;
|
tree var;
|
ssa_op_iter iter;
|
ssa_op_iter iter;
|
|
|
for (; mem_refs; mem_refs = mem_refs->next)
|
for (; mem_refs; mem_refs = mem_refs->next)
|
{
|
{
|
FOR_EACH_SSA_TREE_OPERAND (var, mem_refs->stmt, iter, SSA_OP_ALL_VIRTUALS)
|
FOR_EACH_SSA_TREE_OPERAND (var, mem_refs->stmt, iter, SSA_OP_ALL_VIRTUALS)
|
mark_sym_for_renaming (SSA_NAME_VAR (var));
|
mark_sym_for_renaming (SSA_NAME_VAR (var));
|
|
|
*mem_refs->ref = tmp_var;
|
*mem_refs->ref = tmp_var;
|
update_stmt (mem_refs->stmt);
|
update_stmt (mem_refs->stmt);
|
}
|
}
|
}
|
}
|
|
|
/* The name and the length of the currently generated variable
|
/* The name and the length of the currently generated variable
|
for lsm. */
|
for lsm. */
|
#define MAX_LSM_NAME_LENGTH 40
|
#define MAX_LSM_NAME_LENGTH 40
|
static char lsm_tmp_name[MAX_LSM_NAME_LENGTH + 1];
|
static char lsm_tmp_name[MAX_LSM_NAME_LENGTH + 1];
|
static int lsm_tmp_name_length;
|
static int lsm_tmp_name_length;
|
|
|
/* Adds S to lsm_tmp_name. */
|
/* Adds S to lsm_tmp_name. */
|
|
|
static void
|
static void
|
lsm_tmp_name_add (const char *s)
|
lsm_tmp_name_add (const char *s)
|
{
|
{
|
int l = strlen (s) + lsm_tmp_name_length;
|
int l = strlen (s) + lsm_tmp_name_length;
|
if (l > MAX_LSM_NAME_LENGTH)
|
if (l > MAX_LSM_NAME_LENGTH)
|
return;
|
return;
|
|
|
strcpy (lsm_tmp_name + lsm_tmp_name_length, s);
|
strcpy (lsm_tmp_name + lsm_tmp_name_length, s);
|
lsm_tmp_name_length = l;
|
lsm_tmp_name_length = l;
|
}
|
}
|
|
|
/* Stores the name for temporary variable that replaces REF to
|
/* Stores the name for temporary variable that replaces REF to
|
lsm_tmp_name. */
|
lsm_tmp_name. */
|
|
|
static void
|
static void
|
gen_lsm_tmp_name (tree ref)
|
gen_lsm_tmp_name (tree ref)
|
{
|
{
|
const char *name;
|
const char *name;
|
|
|
switch (TREE_CODE (ref))
|
switch (TREE_CODE (ref))
|
{
|
{
|
case MISALIGNED_INDIRECT_REF:
|
case MISALIGNED_INDIRECT_REF:
|
case ALIGN_INDIRECT_REF:
|
case ALIGN_INDIRECT_REF:
|
case INDIRECT_REF:
|
case INDIRECT_REF:
|
gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
|
gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
|
lsm_tmp_name_add ("_");
|
lsm_tmp_name_add ("_");
|
break;
|
break;
|
|
|
case BIT_FIELD_REF:
|
case BIT_FIELD_REF:
|
case VIEW_CONVERT_EXPR:
|
case VIEW_CONVERT_EXPR:
|
case ARRAY_RANGE_REF:
|
case ARRAY_RANGE_REF:
|
gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
|
gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
|
break;
|
break;
|
|
|
case REALPART_EXPR:
|
case REALPART_EXPR:
|
gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
|
gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
|
lsm_tmp_name_add ("_RE");
|
lsm_tmp_name_add ("_RE");
|
break;
|
break;
|
|
|
case IMAGPART_EXPR:
|
case IMAGPART_EXPR:
|
gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
|
gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
|
lsm_tmp_name_add ("_IM");
|
lsm_tmp_name_add ("_IM");
|
break;
|
break;
|
|
|
case COMPONENT_REF:
|
case COMPONENT_REF:
|
gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
|
gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
|
lsm_tmp_name_add ("_");
|
lsm_tmp_name_add ("_");
|
name = get_name (TREE_OPERAND (ref, 1));
|
name = get_name (TREE_OPERAND (ref, 1));
|
if (!name)
|
if (!name)
|
name = "F";
|
name = "F";
|
lsm_tmp_name_add ("_");
|
lsm_tmp_name_add ("_");
|
lsm_tmp_name_add (name);
|
lsm_tmp_name_add (name);
|
|
|
case ARRAY_REF:
|
case ARRAY_REF:
|
gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
|
gen_lsm_tmp_name (TREE_OPERAND (ref, 0));
|
lsm_tmp_name_add ("_I");
|
lsm_tmp_name_add ("_I");
|
break;
|
break;
|
|
|
case SSA_NAME:
|
case SSA_NAME:
|
ref = SSA_NAME_VAR (ref);
|
ref = SSA_NAME_VAR (ref);
|
/* Fallthru. */
|
/* Fallthru. */
|
|
|
case VAR_DECL:
|
case VAR_DECL:
|
case PARM_DECL:
|
case PARM_DECL:
|
name = get_name (ref);
|
name = get_name (ref);
|
if (!name)
|
if (!name)
|
name = "D";
|
name = "D";
|
lsm_tmp_name_add (name);
|
lsm_tmp_name_add (name);
|
break;
|
break;
|
|
|
case STRING_CST:
|
case STRING_CST:
|
lsm_tmp_name_add ("S");
|
lsm_tmp_name_add ("S");
|
break;
|
break;
|
|
|
case RESULT_DECL:
|
case RESULT_DECL:
|
lsm_tmp_name_add ("R");
|
lsm_tmp_name_add ("R");
|
break;
|
break;
|
|
|
default:
|
default:
|
gcc_unreachable ();
|
gcc_unreachable ();
|
}
|
}
|
}
|
}
|
|
|
/* Determines name for temporary variable that replaces REF.
|
/* Determines name for temporary variable that replaces REF.
|
The name is accumulated into the lsm_tmp_name variable. */
|
The name is accumulated into the lsm_tmp_name variable. */
|
|
|
static char *
|
static char *
|
get_lsm_tmp_name (tree ref)
|
get_lsm_tmp_name (tree ref)
|
{
|
{
|
lsm_tmp_name_length = 0;
|
lsm_tmp_name_length = 0;
|
gen_lsm_tmp_name (ref);
|
gen_lsm_tmp_name (ref);
|
lsm_tmp_name_add ("_lsm");
|
lsm_tmp_name_add ("_lsm");
|
return lsm_tmp_name;
|
return lsm_tmp_name;
|
}
|
}
|
|
|
/* Records request for store motion of memory reference REF from LOOP.
|
/* Records request for store motion of memory reference REF from LOOP.
|
MEM_REFS is the list of occurrences of the reference REF inside LOOP;
|
MEM_REFS is the list of occurrences of the reference REF inside LOOP;
|
these references are rewritten by a new temporary variable.
|
these references are rewritten by a new temporary variable.
|
Exits from the LOOP are stored in EXITS, there are N_EXITS of them.
|
Exits from the LOOP are stored in EXITS, there are N_EXITS of them.
|
The initialization of the temporary variable is put to the preheader
|
The initialization of the temporary variable is put to the preheader
|
of the loop, and assignments to the reference from the temporary variable
|
of the loop, and assignments to the reference from the temporary variable
|
are emitted to exits. */
|
are emitted to exits. */
|
|
|
static void
|
static void
|
schedule_sm (struct loop *loop, edge *exits, unsigned n_exits, tree ref,
|
schedule_sm (struct loop *loop, edge *exits, unsigned n_exits, tree ref,
|
struct mem_ref_loc *mem_refs)
|
struct mem_ref_loc *mem_refs)
|
{
|
{
|
struct mem_ref_loc *aref;
|
struct mem_ref_loc *aref;
|
tree tmp_var;
|
tree tmp_var;
|
unsigned i;
|
unsigned i;
|
tree load, store;
|
tree load, store;
|
struct fmt_data fmt_data;
|
struct fmt_data fmt_data;
|
|
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
if (dump_file && (dump_flags & TDF_DETAILS))
|
{
|
{
|
fprintf (dump_file, "Executing store motion of ");
|
fprintf (dump_file, "Executing store motion of ");
|
print_generic_expr (dump_file, ref, 0);
|
print_generic_expr (dump_file, ref, 0);
|
fprintf (dump_file, " from loop %d\n", loop->num);
|
fprintf (dump_file, " from loop %d\n", loop->num);
|
}
|
}
|
|
|
tmp_var = make_rename_temp (TREE_TYPE (ref),
|
tmp_var = make_rename_temp (TREE_TYPE (ref),
|
get_lsm_tmp_name (ref));
|
get_lsm_tmp_name (ref));
|
|
|
fmt_data.loop = loop;
|
fmt_data.loop = loop;
|
fmt_data.orig_loop = loop;
|
fmt_data.orig_loop = loop;
|
for_each_index (&ref, force_move_till, &fmt_data);
|
for_each_index (&ref, force_move_till, &fmt_data);
|
|
|
rewrite_mem_refs (tmp_var, mem_refs);
|
rewrite_mem_refs (tmp_var, mem_refs);
|
for (aref = mem_refs; aref; aref = aref->next)
|
for (aref = mem_refs; aref; aref = aref->next)
|
if (LIM_DATA (aref->stmt))
|
if (LIM_DATA (aref->stmt))
|
LIM_DATA (aref->stmt)->sm_done = true;
|
LIM_DATA (aref->stmt)->sm_done = true;
|
|
|
/* Emit the load & stores. */
|
/* Emit the load & stores. */
|
load = build2 (MODIFY_EXPR, void_type_node, tmp_var, ref);
|
load = build2 (MODIFY_EXPR, void_type_node, tmp_var, ref);
|
get_stmt_ann (load)->common.aux = xcalloc (1, sizeof (struct lim_aux_data));
|
get_stmt_ann (load)->common.aux = xcalloc (1, sizeof (struct lim_aux_data));
|
LIM_DATA (load)->max_loop = loop;
|
LIM_DATA (load)->max_loop = loop;
|
LIM_DATA (load)->tgt_loop = loop;
|
LIM_DATA (load)->tgt_loop = loop;
|
|
|
/* Put this into the latch, so that we are sure it will be processed after
|
/* Put this into the latch, so that we are sure it will be processed after
|
all dependencies. */
|
all dependencies. */
|
bsi_insert_on_edge (loop_latch_edge (loop), load);
|
bsi_insert_on_edge (loop_latch_edge (loop), load);
|
|
|
for (i = 0; i < n_exits; i++)
|
for (i = 0; i < n_exits; i++)
|
{
|
{
|
store = build2 (MODIFY_EXPR, void_type_node,
|
store = build2 (MODIFY_EXPR, void_type_node,
|
unshare_expr (ref), tmp_var);
|
unshare_expr (ref), tmp_var);
|
bsi_insert_on_edge (exits[i], store);
|
bsi_insert_on_edge (exits[i], store);
|
}
|
}
|
}
|
}
|
|
|
/* Check whether memory reference REF can be hoisted out of the LOOP. If this
|
/* Check whether memory reference REF can be hoisted out of the LOOP. If this
|
is true, prepare the statements that load the value of the memory reference
|
is true, prepare the statements that load the value of the memory reference
|
to a temporary variable in the loop preheader, store it back on the loop
|
to a temporary variable in the loop preheader, store it back on the loop
|
exits, and replace all the references inside LOOP by this temporary variable.
|
exits, and replace all the references inside LOOP by this temporary variable.
|
LOOP has N_EXITS stored in EXITS. CLOBBERED_VOPS is the bitmap of virtual
|
LOOP has N_EXITS stored in EXITS. CLOBBERED_VOPS is the bitmap of virtual
|
operands that are clobbered by a call or accessed through multiple references
|
operands that are clobbered by a call or accessed through multiple references
|
in loop. */
|
in loop. */
|
|
|
static void
|
static void
|
determine_lsm_ref (struct loop *loop, edge *exits, unsigned n_exits,
|
determine_lsm_ref (struct loop *loop, edge *exits, unsigned n_exits,
|
bitmap clobbered_vops, struct mem_ref *ref)
|
bitmap clobbered_vops, struct mem_ref *ref)
|
{
|
{
|
struct mem_ref_loc *aref;
|
struct mem_ref_loc *aref;
|
struct loop *must_exec;
|
struct loop *must_exec;
|
|
|
/* In case the memory is not stored to, there is nothing for SM to do. */
|
/* In case the memory is not stored to, there is nothing for SM to do. */
|
if (!ref->is_stored)
|
if (!ref->is_stored)
|
return;
|
return;
|
|
|
/* If the reference is aliased with any different ref, or killed by call
|
/* If the reference is aliased with any different ref, or killed by call
|
in function, then fail. */
|
in function, then fail. */
|
if (bitmap_intersect_p (ref->vops, clobbered_vops))
|
if (bitmap_intersect_p (ref->vops, clobbered_vops))
|
return;
|
return;
|
|
|
if (tree_could_trap_p (ref->mem))
|
if (tree_could_trap_p (ref->mem))
|
{
|
{
|
/* If the memory access is unsafe (i.e. it might trap), ensure that some
|
/* If the memory access is unsafe (i.e. it might trap), ensure that some
|
of the statements in that it occurs is always executed when the loop
|
of the statements in that it occurs is always executed when the loop
|
is entered. This way we know that by moving the load from the
|
is entered. This way we know that by moving the load from the
|
reference out of the loop we will not cause the error that would not
|
reference out of the loop we will not cause the error that would not
|
occur otherwise.
|
occur otherwise.
|
|
|
TODO -- in fact we would like to check for anticipability of the
|
TODO -- in fact we would like to check for anticipability of the
|
reference, i.e. that on each path from loop entry to loop exit at
|
reference, i.e. that on each path from loop entry to loop exit at
|
least one of the statements containing the memory reference is
|
least one of the statements containing the memory reference is
|
executed. */
|
executed. */
|
|
|
for (aref = ref->locs; aref; aref = aref->next)
|
for (aref = ref->locs; aref; aref = aref->next)
|
{
|
{
|
if (!LIM_DATA (aref->stmt))
|
if (!LIM_DATA (aref->stmt))
|
continue;
|
continue;
|
|
|
must_exec = LIM_DATA (aref->stmt)->always_executed_in;
|
must_exec = LIM_DATA (aref->stmt)->always_executed_in;
|
if (!must_exec)
|
if (!must_exec)
|
continue;
|
continue;
|
|
|
if (must_exec == loop
|
if (must_exec == loop
|
|| flow_loop_nested_p (must_exec, loop))
|
|| flow_loop_nested_p (must_exec, loop))
|
break;
|
break;
|
}
|
}
|
|
|
if (!aref)
|
if (!aref)
|
return;
|
return;
|
}
|
}
|
|
|
schedule_sm (loop, exits, n_exits, ref->mem, ref->locs);
|
schedule_sm (loop, exits, n_exits, ref->mem, ref->locs);
|
}
|
}
|
|
|
/* Hoists memory references MEM_REFS out of LOOP. CLOBBERED_VOPS is the list
|
/* Hoists memory references MEM_REFS out of LOOP. CLOBBERED_VOPS is the list
|
of vops clobbered by call in loop or accessed by multiple memory references.
|
of vops clobbered by call in loop or accessed by multiple memory references.
|
EXITS is the list of N_EXITS exit edges of the LOOP. */
|
EXITS is the list of N_EXITS exit edges of the LOOP. */
|
|
|
static void
|
static void
|
hoist_memory_references (struct loop *loop, struct mem_ref *mem_refs,
|
hoist_memory_references (struct loop *loop, struct mem_ref *mem_refs,
|
bitmap clobbered_vops, edge *exits, unsigned n_exits)
|
bitmap clobbered_vops, edge *exits, unsigned n_exits)
|
{
|
{
|
struct mem_ref *ref;
|
struct mem_ref *ref;
|
|
|
for (ref = mem_refs; ref; ref = ref->next)
|
for (ref = mem_refs; ref; ref = ref->next)
|
determine_lsm_ref (loop, exits, n_exits, clobbered_vops, ref);
|
determine_lsm_ref (loop, exits, n_exits, clobbered_vops, ref);
|
}
|
}
|
|
|
/* Checks whether LOOP (with N_EXITS exits stored in EXITS array) is suitable
|
/* Checks whether LOOP (with N_EXITS exits stored in EXITS array) is suitable
|
for a store motion optimization (i.e. whether we can insert statement
|
for a store motion optimization (i.e. whether we can insert statement
|
on its exits). */
|
on its exits). */
|
|
|
static bool
|
static bool
|
loop_suitable_for_sm (struct loop *loop ATTRIBUTE_UNUSED, edge *exits,
|
loop_suitable_for_sm (struct loop *loop ATTRIBUTE_UNUSED, edge *exits,
|
unsigned n_exits)
|
unsigned n_exits)
|
{
|
{
|
unsigned i;
|
unsigned i;
|
|
|
for (i = 0; i < n_exits; i++)
|
for (i = 0; i < n_exits; i++)
|
if (exits[i]->flags & EDGE_ABNORMAL)
|
if (exits[i]->flags & EDGE_ABNORMAL)
|
return false;
|
return false;
|
|
|
return true;
|
return true;
|
}
|
}
|
|
|
/* A hash function for struct mem_ref object OBJ. */
|
/* A hash function for struct mem_ref object OBJ. */
|
|
|
static hashval_t
|
static hashval_t
|
memref_hash (const void *obj)
|
memref_hash (const void *obj)
|
{
|
{
|
const struct mem_ref *mem = obj;
|
const struct mem_ref *mem = obj;
|
|
|
return mem->hash;
|
return mem->hash;
|
}
|
}
|
|
|
/* An equality function for struct mem_ref object OBJ1 with
|
/* An equality function for struct mem_ref object OBJ1 with
|
memory reference OBJ2. */
|
memory reference OBJ2. */
|
|
|
static int
|
static int
|
memref_eq (const void *obj1, const void *obj2)
|
memref_eq (const void *obj1, const void *obj2)
|
{
|
{
|
const struct mem_ref *mem1 = obj1;
|
const struct mem_ref *mem1 = obj1;
|
|
|
return operand_equal_p (mem1->mem, (tree) obj2, 0);
|
return operand_equal_p (mem1->mem, (tree) obj2, 0);
|
}
|
}
|
|
|
/* Gathers memory references in statement STMT in LOOP, storing the
|
/* Gathers memory references in statement STMT in LOOP, storing the
|
information about them in MEM_REFS hash table. Note vops accessed through
|
information about them in MEM_REFS hash table. Note vops accessed through
|
unrecognized statements in CLOBBERED_VOPS. The newly created references
|
unrecognized statements in CLOBBERED_VOPS. The newly created references
|
are also stored to MEM_REF_LIST. */
|
are also stored to MEM_REF_LIST. */
|
|
|
static void
|
static void
|
gather_mem_refs_stmt (struct loop *loop, htab_t mem_refs,
|
gather_mem_refs_stmt (struct loop *loop, htab_t mem_refs,
|
bitmap clobbered_vops, tree stmt,
|
bitmap clobbered_vops, tree stmt,
|
struct mem_ref **mem_ref_list)
|
struct mem_ref **mem_ref_list)
|
{
|
{
|
tree *lhs, *rhs, *mem = NULL;
|
tree *lhs, *rhs, *mem = NULL;
|
hashval_t hash;
|
hashval_t hash;
|
PTR *slot;
|
PTR *slot;
|
struct mem_ref *ref = NULL;
|
struct mem_ref *ref = NULL;
|
ssa_op_iter oi;
|
ssa_op_iter oi;
|
tree vname;
|
tree vname;
|
bool is_stored;
|
bool is_stored;
|
|
|
if (ZERO_SSA_OPERANDS (stmt, SSA_OP_ALL_VIRTUALS))
|
if (ZERO_SSA_OPERANDS (stmt, SSA_OP_ALL_VIRTUALS))
|
return;
|
return;
|
|
|
/* Recognize MEM = (SSA_NAME | invariant) and SSA_NAME = MEM patterns. */
|
/* Recognize MEM = (SSA_NAME | invariant) and SSA_NAME = MEM patterns. */
|
if (TREE_CODE (stmt) != MODIFY_EXPR)
|
if (TREE_CODE (stmt) != MODIFY_EXPR)
|
goto fail;
|
goto fail;
|
|
|
lhs = &TREE_OPERAND (stmt, 0);
|
lhs = &TREE_OPERAND (stmt, 0);
|
rhs = &TREE_OPERAND (stmt, 1);
|
rhs = &TREE_OPERAND (stmt, 1);
|
|
|
if (TREE_CODE (*lhs) == SSA_NAME)
|
if (TREE_CODE (*lhs) == SSA_NAME)
|
{
|
{
|
if (!is_gimple_addressable (*rhs))
|
if (!is_gimple_addressable (*rhs))
|
goto fail;
|
goto fail;
|
|
|
mem = rhs;
|
mem = rhs;
|
is_stored = false;
|
is_stored = false;
|
}
|
}
|
else if (TREE_CODE (*rhs) == SSA_NAME
|
else if (TREE_CODE (*rhs) == SSA_NAME
|
|| is_gimple_min_invariant (*rhs))
|
|| is_gimple_min_invariant (*rhs))
|
{
|
{
|
mem = lhs;
|
mem = lhs;
|
is_stored = true;
|
is_stored = true;
|
}
|
}
|
else
|
else
|
goto fail;
|
goto fail;
|
|
|
/* If we cannot create an SSA name for the result, give up. */
|
/* If we cannot create an SSA name for the result, give up. */
|
if (!is_gimple_reg_type (TREE_TYPE (*mem))
|
if (!is_gimple_reg_type (TREE_TYPE (*mem))
|
|| TREE_THIS_VOLATILE (*mem))
|
|| TREE_THIS_VOLATILE (*mem))
|
goto fail;
|
goto fail;
|
|
|
/* If we cannot move the reference out of the loop, fail. */
|
/* If we cannot move the reference out of the loop, fail. */
|
if (!for_each_index (mem, may_move_till, loop))
|
if (!for_each_index (mem, may_move_till, loop))
|
goto fail;
|
goto fail;
|
|
|
hash = iterative_hash_expr (*mem, 0);
|
hash = iterative_hash_expr (*mem, 0);
|
slot = htab_find_slot_with_hash (mem_refs, *mem, hash, INSERT);
|
slot = htab_find_slot_with_hash (mem_refs, *mem, hash, INSERT);
|
|
|
if (*slot)
|
if (*slot)
|
ref = *slot;
|
ref = *slot;
|
else
|
else
|
{
|
{
|
ref = XNEW (struct mem_ref);
|
ref = XNEW (struct mem_ref);
|
ref->mem = *mem;
|
ref->mem = *mem;
|
ref->hash = hash;
|
ref->hash = hash;
|
ref->locs = NULL;
|
ref->locs = NULL;
|
ref->is_stored = false;
|
ref->is_stored = false;
|
ref->vops = BITMAP_ALLOC (NULL);
|
ref->vops = BITMAP_ALLOC (NULL);
|
ref->next = *mem_ref_list;
|
ref->next = *mem_ref_list;
|
*mem_ref_list = ref;
|
*mem_ref_list = ref;
|
*slot = ref;
|
*slot = ref;
|
}
|
}
|
ref->is_stored |= is_stored;
|
ref->is_stored |= is_stored;
|
|
|
FOR_EACH_SSA_TREE_OPERAND (vname, stmt, oi,
|
FOR_EACH_SSA_TREE_OPERAND (vname, stmt, oi,
|
SSA_OP_VIRTUAL_USES | SSA_OP_VIRTUAL_KILLS)
|
SSA_OP_VIRTUAL_USES | SSA_OP_VIRTUAL_KILLS)
|
bitmap_set_bit (ref->vops, DECL_UID (SSA_NAME_VAR (vname)));
|
bitmap_set_bit (ref->vops, DECL_UID (SSA_NAME_VAR (vname)));
|
record_mem_ref_loc (&ref->locs, stmt, mem);
|
record_mem_ref_loc (&ref->locs, stmt, mem);
|
return;
|
return;
|
|
|
fail:
|
fail:
|
FOR_EACH_SSA_TREE_OPERAND (vname, stmt, oi,
|
FOR_EACH_SSA_TREE_OPERAND (vname, stmt, oi,
|
SSA_OP_VIRTUAL_USES | SSA_OP_VIRTUAL_KILLS)
|
SSA_OP_VIRTUAL_USES | SSA_OP_VIRTUAL_KILLS)
|
bitmap_set_bit (clobbered_vops, DECL_UID (SSA_NAME_VAR (vname)));
|
bitmap_set_bit (clobbered_vops, DECL_UID (SSA_NAME_VAR (vname)));
|
}
|
}
|
|
|
/* Gathers memory references in LOOP. Notes vops accessed through unrecognized
|
/* Gathers memory references in LOOP. Notes vops accessed through unrecognized
|
statements in CLOBBERED_VOPS. The list of the references found by
|
statements in CLOBBERED_VOPS. The list of the references found by
|
the function is returned. */
|
the function is returned. */
|
|
|
static struct mem_ref *
|
static struct mem_ref *
|
gather_mem_refs (struct loop *loop, bitmap clobbered_vops)
|
gather_mem_refs (struct loop *loop, bitmap clobbered_vops)
|
{
|
{
|
basic_block *body = get_loop_body (loop);
|
basic_block *body = get_loop_body (loop);
|
block_stmt_iterator bsi;
|
block_stmt_iterator bsi;
|
unsigned i;
|
unsigned i;
|
struct mem_ref *mem_ref_list = NULL;
|
struct mem_ref *mem_ref_list = NULL;
|
htab_t mem_refs = htab_create (100, memref_hash, memref_eq, NULL);
|
htab_t mem_refs = htab_create (100, memref_hash, memref_eq, NULL);
|
|
|
for (i = 0; i < loop->num_nodes; i++)
|
for (i = 0; i < loop->num_nodes; i++)
|
{
|
{
|
for (bsi = bsi_start (body[i]); !bsi_end_p (bsi); bsi_next (&bsi))
|
for (bsi = bsi_start (body[i]); !bsi_end_p (bsi); bsi_next (&bsi))
|
gather_mem_refs_stmt (loop, mem_refs, clobbered_vops, bsi_stmt (bsi),
|
gather_mem_refs_stmt (loop, mem_refs, clobbered_vops, bsi_stmt (bsi),
|
&mem_ref_list);
|
&mem_ref_list);
|
}
|
}
|
|
|
free (body);
|
free (body);
|
|
|
htab_delete (mem_refs);
|
htab_delete (mem_refs);
|
return mem_ref_list;
|
return mem_ref_list;
|
}
|
}
|
|
|
/* Finds the vops accessed by more than one of the memory references described
|
/* Finds the vops accessed by more than one of the memory references described
|
in MEM_REFS and marks them in CLOBBERED_VOPS. */
|
in MEM_REFS and marks them in CLOBBERED_VOPS. */
|
|
|
static void
|
static void
|
find_more_ref_vops (struct mem_ref *mem_refs, bitmap clobbered_vops)
|
find_more_ref_vops (struct mem_ref *mem_refs, bitmap clobbered_vops)
|
{
|
{
|
bitmap_head tmp, all_vops;
|
bitmap_head tmp, all_vops;
|
struct mem_ref *ref;
|
struct mem_ref *ref;
|
|
|
bitmap_initialize (&tmp, &bitmap_default_obstack);
|
bitmap_initialize (&tmp, &bitmap_default_obstack);
|
bitmap_initialize (&all_vops, &bitmap_default_obstack);
|
bitmap_initialize (&all_vops, &bitmap_default_obstack);
|
|
|
for (ref = mem_refs; ref; ref = ref->next)
|
for (ref = mem_refs; ref; ref = ref->next)
|
{
|
{
|
/* The vops that are already in all_vops are accessed by more than
|
/* The vops that are already in all_vops are accessed by more than
|
one memory reference. */
|
one memory reference. */
|
bitmap_and (&tmp, &all_vops, ref->vops);
|
bitmap_and (&tmp, &all_vops, ref->vops);
|
bitmap_ior_into (clobbered_vops, &tmp);
|
bitmap_ior_into (clobbered_vops, &tmp);
|
bitmap_clear (&tmp);
|
bitmap_clear (&tmp);
|
|
|
bitmap_ior_into (&all_vops, ref->vops);
|
bitmap_ior_into (&all_vops, ref->vops);
|
}
|
}
|
|
|
bitmap_clear (&all_vops);
|
bitmap_clear (&all_vops);
|
}
|
}
|
|
|
/* Releases the memory occupied by REF. */
|
/* Releases the memory occupied by REF. */
|
|
|
static void
|
static void
|
free_mem_ref (struct mem_ref *ref)
|
free_mem_ref (struct mem_ref *ref)
|
{
|
{
|
free_mem_ref_locs (ref->locs);
|
free_mem_ref_locs (ref->locs);
|
BITMAP_FREE (ref->vops);
|
BITMAP_FREE (ref->vops);
|
free (ref);
|
free (ref);
|
}
|
}
|
|
|
/* Releases the memory occupied by REFS. */
|
/* Releases the memory occupied by REFS. */
|
|
|
static void
|
static void
|
free_mem_refs (struct mem_ref *refs)
|
free_mem_refs (struct mem_ref *refs)
|
{
|
{
|
struct mem_ref *ref, *next;
|
struct mem_ref *ref, *next;
|
|
|
for (ref = refs; ref; ref = next)
|
for (ref = refs; ref; ref = next)
|
{
|
{
|
next = ref->next;
|
next = ref->next;
|
free_mem_ref (ref);
|
free_mem_ref (ref);
|
}
|
}
|
}
|
}
|
|
|
/* Try to perform store motion for all memory references modified inside
|
/* Try to perform store motion for all memory references modified inside
|
LOOP. */
|
LOOP. */
|
|
|
static void
|
static void
|
determine_lsm_loop (struct loop *loop)
|
determine_lsm_loop (struct loop *loop)
|
{
|
{
|
unsigned n_exits;
|
unsigned n_exits;
|
edge *exits = get_loop_exit_edges (loop, &n_exits);
|
edge *exits = get_loop_exit_edges (loop, &n_exits);
|
bitmap clobbered_vops;
|
bitmap clobbered_vops;
|
struct mem_ref *mem_refs;
|
struct mem_ref *mem_refs;
|
|
|
if (!loop_suitable_for_sm (loop, exits, n_exits))
|
if (!loop_suitable_for_sm (loop, exits, n_exits))
|
{
|
{
|
free (exits);
|
free (exits);
|
return;
|
return;
|
}
|
}
|
|
|
/* Find the memory references in LOOP. */
|
/* Find the memory references in LOOP. */
|
clobbered_vops = BITMAP_ALLOC (NULL);
|
clobbered_vops = BITMAP_ALLOC (NULL);
|
mem_refs = gather_mem_refs (loop, clobbered_vops);
|
mem_refs = gather_mem_refs (loop, clobbered_vops);
|
|
|
/* Find the vops that are used for more than one reference. */
|
/* Find the vops that are used for more than one reference. */
|
find_more_ref_vops (mem_refs, clobbered_vops);
|
find_more_ref_vops (mem_refs, clobbered_vops);
|
|
|
/* Hoist all suitable memory references. */
|
/* Hoist all suitable memory references. */
|
hoist_memory_references (loop, mem_refs, clobbered_vops, exits, n_exits);
|
hoist_memory_references (loop, mem_refs, clobbered_vops, exits, n_exits);
|
|
|
free_mem_refs (mem_refs);
|
free_mem_refs (mem_refs);
|
free (exits);
|
free (exits);
|
BITMAP_FREE (clobbered_vops);
|
BITMAP_FREE (clobbered_vops);
|
}
|
}
|
|
|
/* Try to perform store motion for all memory references modified inside
|
/* Try to perform store motion for all memory references modified inside
|
any of LOOPS. */
|
any of LOOPS. */
|
|
|
static void
|
static void
|
determine_lsm (struct loops *loops)
|
determine_lsm (struct loops *loops)
|
{
|
{
|
struct loop *loop;
|
struct loop *loop;
|
|
|
if (!loops->tree_root->inner)
|
if (!loops->tree_root->inner)
|
return;
|
return;
|
|
|
/* Pass the loops from the outermost and perform the store motion as
|
/* Pass the loops from the outermost and perform the store motion as
|
suitable. */
|
suitable. */
|
|
|
loop = loops->tree_root->inner;
|
loop = loops->tree_root->inner;
|
while (1)
|
while (1)
|
{
|
{
|
determine_lsm_loop (loop);
|
determine_lsm_loop (loop);
|
|
|
if (loop->inner)
|
if (loop->inner)
|
{
|
{
|
loop = loop->inner;
|
loop = loop->inner;
|
continue;
|
continue;
|
}
|
}
|
while (!loop->next)
|
while (!loop->next)
|
{
|
{
|
loop = loop->outer;
|
loop = loop->outer;
|
if (loop == loops->tree_root)
|
if (loop == loops->tree_root)
|
{
|
{
|
loop_commit_inserts ();
|
loop_commit_inserts ();
|
return;
|
return;
|
}
|
}
|
}
|
}
|
loop = loop->next;
|
loop = loop->next;
|
}
|
}
|
}
|
}
|
|
|
/* Fills ALWAYS_EXECUTED_IN information for basic blocks of LOOP, i.e.
|
/* Fills ALWAYS_EXECUTED_IN information for basic blocks of LOOP, i.e.
|
for each such basic block bb records the outermost loop for that execution
|
for each such basic block bb records the outermost loop for that execution
|
of its header implies execution of bb. CONTAINS_CALL is the bitmap of
|
of its header implies execution of bb. CONTAINS_CALL is the bitmap of
|
blocks that contain a nonpure call. */
|
blocks that contain a nonpure call. */
|
|
|
static void
|
static void
|
fill_always_executed_in (struct loop *loop, sbitmap contains_call)
|
fill_always_executed_in (struct loop *loop, sbitmap contains_call)
|
{
|
{
|
basic_block bb = NULL, *bbs, last = NULL;
|
basic_block bb = NULL, *bbs, last = NULL;
|
unsigned i;
|
unsigned i;
|
edge e;
|
edge e;
|
struct loop *inn_loop = loop;
|
struct loop *inn_loop = loop;
|
|
|
if (!loop->header->aux)
|
if (!loop->header->aux)
|
{
|
{
|
bbs = get_loop_body_in_dom_order (loop);
|
bbs = get_loop_body_in_dom_order (loop);
|
|
|
for (i = 0; i < loop->num_nodes; i++)
|
for (i = 0; i < loop->num_nodes; i++)
|
{
|
{
|
edge_iterator ei;
|
edge_iterator ei;
|
bb = bbs[i];
|
bb = bbs[i];
|
|
|
if (dominated_by_p (CDI_DOMINATORS, loop->latch, bb))
|
if (dominated_by_p (CDI_DOMINATORS, loop->latch, bb))
|
last = bb;
|
last = bb;
|
|
|
if (TEST_BIT (contains_call, bb->index))
|
if (TEST_BIT (contains_call, bb->index))
|
break;
|
break;
|
|
|
FOR_EACH_EDGE (e, ei, bb->succs)
|
FOR_EACH_EDGE (e, ei, bb->succs)
|
if (!flow_bb_inside_loop_p (loop, e->dest))
|
if (!flow_bb_inside_loop_p (loop, e->dest))
|
break;
|
break;
|
if (e)
|
if (e)
|
break;
|
break;
|
|
|
/* A loop might be infinite (TODO use simple loop analysis
|
/* A loop might be infinite (TODO use simple loop analysis
|
to disprove this if possible). */
|
to disprove this if possible). */
|
if (bb->flags & BB_IRREDUCIBLE_LOOP)
|
if (bb->flags & BB_IRREDUCIBLE_LOOP)
|
break;
|
break;
|
|
|
if (!flow_bb_inside_loop_p (inn_loop, bb))
|
if (!flow_bb_inside_loop_p (inn_loop, bb))
|
break;
|
break;
|
|
|
if (bb->loop_father->header == bb)
|
if (bb->loop_father->header == bb)
|
{
|
{
|
if (!dominated_by_p (CDI_DOMINATORS, loop->latch, bb))
|
if (!dominated_by_p (CDI_DOMINATORS, loop->latch, bb))
|
break;
|
break;
|
|
|
/* In a loop that is always entered we may proceed anyway.
|
/* In a loop that is always entered we may proceed anyway.
|
But record that we entered it and stop once we leave it. */
|
But record that we entered it and stop once we leave it. */
|
inn_loop = bb->loop_father;
|
inn_loop = bb->loop_father;
|
}
|
}
|
}
|
}
|
|
|
while (1)
|
while (1)
|
{
|
{
|
last->aux = loop;
|
last->aux = loop;
|
if (last == loop->header)
|
if (last == loop->header)
|
break;
|
break;
|
last = get_immediate_dominator (CDI_DOMINATORS, last);
|
last = get_immediate_dominator (CDI_DOMINATORS, last);
|
}
|
}
|
|
|
free (bbs);
|
free (bbs);
|
}
|
}
|
|
|
for (loop = loop->inner; loop; loop = loop->next)
|
for (loop = loop->inner; loop; loop = loop->next)
|
fill_always_executed_in (loop, contains_call);
|
fill_always_executed_in (loop, contains_call);
|
}
|
}
|
|
|
/* Compute the global information needed by the loop invariant motion pass.
|
/* Compute the global information needed by the loop invariant motion pass.
|
LOOPS is the loop tree. */
|
LOOPS is the loop tree. */
|
|
|
static void
|
static void
|
tree_ssa_lim_initialize (struct loops *loops)
|
tree_ssa_lim_initialize (struct loops *loops)
|
{
|
{
|
sbitmap contains_call = sbitmap_alloc (last_basic_block);
|
sbitmap contains_call = sbitmap_alloc (last_basic_block);
|
block_stmt_iterator bsi;
|
block_stmt_iterator bsi;
|
struct loop *loop;
|
struct loop *loop;
|
basic_block bb;
|
basic_block bb;
|
|
|
sbitmap_zero (contains_call);
|
sbitmap_zero (contains_call);
|
FOR_EACH_BB (bb)
|
FOR_EACH_BB (bb)
|
{
|
{
|
for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
|
for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi))
|
{
|
{
|
if (nonpure_call_p (bsi_stmt (bsi)))
|
if (nonpure_call_p (bsi_stmt (bsi)))
|
break;
|
break;
|
}
|
}
|
|
|
if (!bsi_end_p (bsi))
|
if (!bsi_end_p (bsi))
|
SET_BIT (contains_call, bb->index);
|
SET_BIT (contains_call, bb->index);
|
}
|
}
|
|
|
for (loop = loops->tree_root->inner; loop; loop = loop->next)
|
for (loop = loops->tree_root->inner; loop; loop = loop->next)
|
fill_always_executed_in (loop, contains_call);
|
fill_always_executed_in (loop, contains_call);
|
|
|
sbitmap_free (contains_call);
|
sbitmap_free (contains_call);
|
}
|
}
|
|
|
/* Cleans up after the invariant motion pass. */
|
/* Cleans up after the invariant motion pass. */
|
|
|
static void
|
static void
|
tree_ssa_lim_finalize (void)
|
tree_ssa_lim_finalize (void)
|
{
|
{
|
basic_block bb;
|
basic_block bb;
|
|
|
FOR_EACH_BB (bb)
|
FOR_EACH_BB (bb)
|
{
|
{
|
bb->aux = NULL;
|
bb->aux = NULL;
|
}
|
}
|
}
|
}
|
|
|
/* Moves invariants from LOOPS. Only "expensive" invariants are moved out --
|
/* Moves invariants from LOOPS. Only "expensive" invariants are moved out --
|
i.e. those that are likely to be win regardless of the register pressure. */
|
i.e. those that are likely to be win regardless of the register pressure. */
|
|
|
void
|
void
|
tree_ssa_lim (struct loops *loops)
|
tree_ssa_lim (struct loops *loops)
|
{
|
{
|
tree_ssa_lim_initialize (loops);
|
tree_ssa_lim_initialize (loops);
|
|
|
/* For each statement determine the outermost loop in that it is
|
/* For each statement determine the outermost loop in that it is
|
invariant and cost for computing the invariant. */
|
invariant and cost for computing the invariant. */
|
determine_invariantness ();
|
determine_invariantness ();
|
|
|
/* For each memory reference determine whether it is possible to hoist it
|
/* For each memory reference determine whether it is possible to hoist it
|
out of the loop. Force the necessary invariants to be moved out of the
|
out of the loop. Force the necessary invariants to be moved out of the
|
loops as well. */
|
loops as well. */
|
determine_lsm (loops);
|
determine_lsm (loops);
|
|
|
/* Move the expressions that are expensive enough. */
|
/* Move the expressions that are expensive enough. */
|
move_computations ();
|
move_computations ();
|
|
|
tree_ssa_lim_finalize ();
|
tree_ssa_lim_finalize ();
|
}
|
}
|
|
|
