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Commit e0ab232e by Revital Eres Committed by Revital Eres
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SMS: Change the ddg's construction 

From-SVN: r127085
parent 80b8eb11
Showing with 89 additions and 97 deletions
gcc/ChangeLog
2007-07-31 Revital Eres <eres@il.ibm.com>
* ddg.c (add_deps_for_def): Rename to...
(add_cross_iteration_register_deps): This. Change implementation
to use only reaching def and def-use chains to construct the
inter loop dependencies.
(add_deps_for_use): Remove function.
(build_inter_loop_deps): Call add_cross_iteration_register_deps
function to build the inter loop dependencies.
* modulo-sched.c (sms_schedule): Build only
reaching def and def-use chains for the propose of the ddg
construction.
2007-07-31 Julian Brown <julian@codesourcery.com>
* config/arm/neon.md (vec_set<mode>_internal, vec_setv2di_internal):
......
gcc/ddg.c
......@@ -223,131 +223,111 @@ create_ddg_dep_no_link (ddg_ptr g, ddg_node_ptr from, ddg_node_ptr to,
add_edge_to_ddg (g, e);
}
/* Given a downwards exposed register def RD, add inter-loop true dependences
for all its uses in the next iteration, and an output dependence to the
first def of the next iteration. */
/* Given a downwards exposed register def LAST_DEF (which is the last
definition of that register in the bb), add inter-loop true dependences
to all its uses in the next iteration, an output dependence to the
first def of the same register (possibly itself) in the next iteration
and anti-dependences from its uses in the current iteration to the
first definition in the next iteration. */
static void
add_deps_for_def (ddg_ptr g, struct df_ref *rd)
add_cross_iteration_register_deps (ddg_ptr g, struct df_ref *last_def)
{
int regno = DF_REF_REGNO (rd);
struct df_ru_bb_info *bb_info = DF_RU_BB_INFO (g->bb);
int regno = DF_REF_REGNO (last_def);
struct df_link *r_use;
int use_before_def = false;
rtx def_insn = DF_REF_INSN (rd);
ddg_node_ptr src_node = get_node_of_insn (g, def_insn);
int has_use_in_bb_p = false;
rtx def_insn = DF_REF_INSN (last_def);
ddg_node_ptr last_def_node = get_node_of_insn (g, def_insn);
ddg_node_ptr use_node;
struct df_rd_bb_info *bb_info = DF_RD_BB_INFO (g->bb);
struct df_ref *first_def = df_bb_regno_first_def_find (g->bb, regno);
gcc_assert (last_def_node);
gcc_assert (first_def);
/* Create and inter-loop true dependence between RD and each of its uses
that is upwards exposed in RD's block. */
for (r_use = DF_REF_CHAIN (rd); r_use != NULL; r_use = r_use->next)
/* Create inter-loop true dependences and anti dependences. */
for (r_use = DF_REF_CHAIN (last_def); r_use != NULL; r_use = r_use->next)
{
if (bitmap_bit_p (bb_info->gen, r_use->ref->id))
{
rtx use_insn = DF_REF_INSN (r_use->ref);
ddg_node_ptr dest_node = get_node_of_insn (g, use_insn);
rtx use_insn = DF_REF_INSN (r_use->ref);
gcc_assert (src_node && dest_node);
if (BLOCK_FOR_INSN (use_insn) != g->bb)
continue;
/* Any such upwards exposed use appears before the rd def. */
use_before_def = true;
create_ddg_dep_no_link (g, src_node, dest_node, TRUE_DEP,
/* ??? Do not handle uses with DF_REF_IN_NOTE notes. */
use_node = get_node_of_insn (g, use_insn);
gcc_assert (use_node);
has_use_in_bb_p = true;
if (use_node->cuid <= last_def_node->cuid)
{
/* Add true deps from last_def to it's uses in the next
iteration. Any such upwards exposed use appears before
the last_def def. */
create_ddg_dep_no_link (g, last_def_node, use_node, TRUE_DEP,
REG_DEP, 1);
}
else
{
/* Add anti deps from last_def's uses in the current iteration
to the first def in the next iteration. We do not add ANTI
dep when there is an intra-loop TRUE dep in the opposite
direction, but use regmoves to fix such disregarded ANTI
deps when broken. If the first_def reaches the USE then
there is such a dep. */
ddg_node_ptr first_def_node = get_node_of_insn (g,
first_def->insn);
gcc_assert (first_def_node);
if (last_def->id != first_def->id)
{
#ifdef ENABLE_CHECKING
gcc_assert (!bitmap_bit_p (bb_info->gen, first_def->id));
#endif
create_ddg_dep_no_link (g, use_node, first_def_node, ANTI_DEP,
REG_DEP, 1);
}
}
}
/* Create an inter-loop output dependence between RD (which is the
last def in its block, being downwards exposed) and the first def
in its block. Avoid creating a self output dependence. Avoid creating
an output dependence if there is a dependence path between the two defs
starting with a true dependence followed by an anti dependence (i.e. if
there is a use between the two defs. */
if (! use_before_def)
/* Create an inter-loop output dependence between LAST_DEF (which is the
last def in its block, being downwards exposed) and the first def in
its block. Avoid creating a self output dependence. Avoid creating
an output dependence if there is a dependence path between the two
defs starting with a true dependence to a use which can be in the
next iteration; followed by an anti dependence of that use to the
first def (i.e. if there is a use between the two defs.) */
if (!has_use_in_bb_p)
{
struct df_ref *def = df_bb_regno_first_def_find (g->bb, regno);
int i;
ddg_node_ptr dest_node;
if (!def || rd->id == def->id)
if (last_def->id == first_def->id)
return;
/* Check if there are uses after RD. */
for (i = src_node->cuid + 1; i < g->num_nodes; i++)
if (df_find_use (g->nodes[i].insn, DF_REF_REG (rd)))
return;
dest_node = get_node_of_insn (g, def->insn);
create_ddg_dep_no_link (g, src_node, dest_node, OUTPUT_DEP, REG_DEP, 1);
dest_node = get_node_of_insn (g, first_def->insn);
gcc_assert (dest_node);
create_ddg_dep_no_link (g, last_def_node, dest_node,
OUTPUT_DEP, REG_DEP, 1);
}
}
/* Given a register USE, add an inter-loop anti dependence to the first
(nearest BLOCK_BEGIN) def of the next iteration, unless USE is followed
by a def in the block. */
static void
add_deps_for_use (ddg_ptr g, struct df_ref *use)
{
int i;
int regno = DF_REF_REGNO (use);
struct df_ref *first_def = df_bb_regno_first_def_find (g->bb, regno);
ddg_node_ptr use_node;
ddg_node_ptr def_node;
struct df_rd_bb_info *bb_info;
bb_info = DF_RD_BB_INFO (g->bb);
if (!first_def)
return;
use_node = get_node_of_insn (g, use->insn);
def_node = get_node_of_insn (g, first_def->insn);
gcc_assert (use_node && def_node);
/* Make sure there are no defs after USE. */
for (i = use_node->cuid + 1; i < g->num_nodes; i++)
if (df_find_def (g->nodes[i].insn, DF_REF_REG (use)))
return;
/* We must not add ANTI dep when there is an intra-loop TRUE dep in
the opposite direction. If the first_def reaches the USE then there is
such a dep. */
if (! bitmap_bit_p (bb_info->gen, first_def->id))
create_ddg_dep_no_link (g, use_node, def_node, ANTI_DEP, REG_DEP, 1);
}
/* Build inter-loop dependencies, by looking at DF analysis backwards. */
static void
build_inter_loop_deps (ddg_ptr g)
{
unsigned rd_num, u_num;
unsigned rd_num;
struct df_rd_bb_info *rd_bb_info;
struct df_ru_bb_info *ru_bb_info;
bitmap_iterator bi;
rd_bb_info = DF_RD_BB_INFO (g->bb);
/* Find inter-loop output and true deps by connecting downward exposed defs
to the first def of the BB and to upwards exposed uses. */
/* Find inter-loop register output, true and anti deps. */
EXECUTE_IF_SET_IN_BITMAP (rd_bb_info->gen, 0, rd_num, bi)
{
struct df_ref *rd = DF_DEFS_GET (rd_num);
add_deps_for_def (g, rd);
}
{
struct df_ref *rd = DF_DEFS_GET (rd_num);
ru_bb_info = DF_RU_BB_INFO (g->bb);
/* Find inter-loop anti deps. We are interested in uses of the block that
appear below all defs; this implies that these uses are killed. */
EXECUTE_IF_SET_IN_BITMAP (ru_bb_info->kill, 0, u_num, bi)
{
struct df_ref *use = DF_USES_GET (u_num);
if (!(DF_REF_FLAGS (use) & DF_REF_IN_NOTE))
/* We are interested in uses of this BB. */
if (BLOCK_FOR_INSN (use->insn) == g->bb)
add_deps_for_use (g, use);
}
add_cross_iteration_register_deps (g, rd);
}
}
/* Given two nodes, analyze their RTL insns and add inter-loop mem deps
to ddg G. */
static void
......
gcc/modulo-sched.c
......@@ -913,9 +913,8 @@ sms_schedule (void)
/* Init Data Flow analysis, to be used in interloop dep calculation. */
df_set_flags (DF_LR_RUN_DCE);
df_rd_add_problem ();
df_ru_add_problem ();
df_note_add_problem ();
df_chain_add_problem (DF_DU_CHAIN + DF_UD_CHAIN);
df_chain_add_problem (DF_DU_CHAIN);
df_analyze ();
regstat_compute_calls_crossed ();
sched_init ();
......
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