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rs6000.c (rs6000_builtin_vectorization_cost): Revise costs for vec_perm and vec_promote_demote down to more natural values.

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2012-07-31  Bill Schmidt  <wschmidt@linux.ibm.com>

	* config/rs6000/rs6000.c (rs6000_builtin_vectorization_cost): Revise
	costs for vec_perm and vec_promote_demote down to more natural values.
	(struct _rs6000_cost_data): New data structure.
	(rs6000_density_test): New function.
	(rs6000_init_cost): Change to use rs6000_cost_data.
	(rs6000_add_stmt_cost): Likewise.
	(rs6000_finish_cost): Perform density test when vectorizing a loop.

From-SVN: r190019
This commit is contained in:
Bill Schmidt 2012-07-31 21:08:41 +00:00 committed by William Schmidt
parent 0e8d854eb8
commit fdc43210e3
2 changed files with 84 additions and 12 deletions
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10
gcc/ChangeLog
View File

@ -1,3 +1,13 @@
2012-07-31 Bill Schmidt <wschmidt@linux.ibm.com>
* config/rs6000/rs6000.c (rs6000_builtin_vectorization_cost): Revise
costs for vec_perm and vec_promote_demote down to more natural values.
(struct _rs6000_cost_data): New data structure.
(rs6000_density_test): New function.
(rs6000_init_cost): Change to use rs6000_cost_data.
(rs6000_add_stmt_cost): Likewise.
(rs6000_finish_cost): Perform density test when vectorizing a loop.
2012-07-31 Steven Bosscher <steven@gcc.gnu.org>
* sched-vis.c (print_exp): Handle FMA explicitly. Simplify handling

86
gcc/config/rs6000/rs6000.c
View File

@ -57,6 +57,7 @@
#include "params.h"
#include "tm-constrs.h"
#include "opts.h"
#include "tree-vectorizer.h"
#if TARGET_XCOFF
#include "xcoffout.h" /* get declarations of xcoff_*_section_name */
#endif
@ -3326,13 +3327,13 @@ rs6000_builtin_vectorization_cost (enum vect_cost_for_stmt type_of_cost,
case vec_perm:
if (TARGET_VSX)
return 4;
return 3;
else
return 1;
case vec_promote_demote:
if (TARGET_VSX)
return 5;
return 4;
else
return 1;
@ -3468,14 +3469,71 @@ rs6000_preferred_simd_mode (enum machine_mode mode)
return word_mode;
}
typedef struct _rs6000_cost_data
{
struct loop *loop_info;
unsigned cost[3];
} rs6000_cost_data;
/* Test for likely overcommitment of vector hardware resources. If a
loop iteration is relatively large, and too large a percentage of
instructions in the loop are vectorized, the cost model may not
adequately reflect delays from unavailable vector resources.
Penalize the loop body cost for this case. */
static void
rs6000_density_test (rs6000_cost_data *data)
{
const int DENSITY_PCT_THRESHOLD = 85;
const int DENSITY_SIZE_THRESHOLD = 70;
const int DENSITY_PENALTY = 10;
struct loop *loop = data->loop_info;
basic_block *bbs = get_loop_body (loop);
int nbbs = loop->num_nodes;
int vec_cost = data->cost[vect_body], not_vec_cost = 0;
int i, density_pct;
for (i = 0; i < nbbs; i++)
{
basic_block bb = bbs[i];
gimple_stmt_iterator gsi;
for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
{
gimple stmt = gsi_stmt (gsi);
stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
if (!STMT_VINFO_RELEVANT_P (stmt_info)
&& !STMT_VINFO_IN_PATTERN_P (stmt_info))
not_vec_cost++;
}
}
density_pct = (vec_cost * 100) / (vec_cost + not_vec_cost);
if (density_pct > DENSITY_PCT_THRESHOLD
&& vec_cost + not_vec_cost > DENSITY_SIZE_THRESHOLD)
{
data->cost[vect_body] = vec_cost * (100 + DENSITY_PENALTY) / 100;
if (vect_print_dump_info (REPORT_DETAILS))
fprintf (vect_dump,
"density %d%%, cost %d exceeds threshold, penalizing "
"loop body cost by %d%%", density_pct,
vec_cost + not_vec_cost, DENSITY_PENALTY);
}
}
/* Implement targetm.vectorize.init_cost. */
static void *
rs6000_init_cost (struct loop *loop_info ATTRIBUTE_UNUSED)
rs6000_init_cost (struct loop *loop_info)
{
unsigned *cost = XNEWVEC (unsigned, 3);
cost[vect_prologue] = cost[vect_body] = cost[vect_epilogue] = 0;
return cost;
rs6000_cost_data *data = XNEW (struct _rs6000_cost_data);
data->loop_info = loop_info;
data->cost[vect_prologue] = 0;
data->cost[vect_body] = 0;
data->cost[vect_epilogue] = 0;
return data;
}
/* Implement targetm.vectorize.add_stmt_cost. */
@ -3485,7 +3543,7 @@ rs6000_add_stmt_cost (void *data, int count, enum vect_cost_for_stmt kind,
struct _stmt_vec_info *stmt_info, int misalign,
enum vect_cost_model_location where)
{
unsigned *cost = (unsigned *) data;
rs6000_cost_data *cost_data = (rs6000_cost_data*) data;
unsigned retval = 0;
if (flag_vect_cost_model)
@ -3500,7 +3558,7 @@ rs6000_add_stmt_cost (void *data, int count, enum vect_cost_for_stmt kind,
count *= 50; /* FIXME. */
retval = (unsigned) (count * stmt_cost);
cost[where] += retval;
cost_data->cost[where] += retval;
}
return retval;
@ -3512,10 +3570,14 @@ static void
rs6000_finish_cost (void *data, unsigned *prologue_cost,
unsigned *body_cost, unsigned *epilogue_cost)
{
unsigned *cost = (unsigned *) data;
*prologue_cost = cost[vect_prologue];
*body_cost = cost[vect_body];
*epilogue_cost = cost[vect_epilogue];
rs6000_cost_data *cost_data = (rs6000_cost_data*) data;
if (cost_data->loop_info)
rs6000_density_test (cost_data);
*prologue_cost = cost_data->cost[vect_prologue];
*body_cost = cost_data->cost[vect_body];
*epilogue_cost = cost_data->cost[vect_epilogue];
}
/* Implement targetm.vectorize.destroy_cost_data. */