diff options
| -rw-r--r-- | gcc/ChangeLog | 8 | ||||
| -rw-r--r-- | gcc/tree-vect-loop.c | 77 | ||||
| -rw-r--r-- | gcc/tree-vectorizer.h | 1 |
3 files changed, 74 insertions, 12 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index dbbe118..e9df431 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2012-10-04 Jan Hubicka <jh@suse.cz> + + * tree-vectorizer.h (vect_estimate_min_profitable_iters): Remove. + * tree-vect-loop.c (vect_estimate_min_profitable_iters): Declare here. + (vect_analyze_loop_operations): Use loop count estimate to rule out + unprofitable vectorization. + (vect_estimate_min_profitable_iters): Return ret_min_profitable_estimate. + 2012-10-05 Jakub Jelinek <jakub@redhat.com> PR tree-optimization/54810 diff --git a/gcc/tree-vect-loop.c b/gcc/tree-vect-loop.c index d01203e..58edfcb 100644 --- a/gcc/tree-vect-loop.c +++ b/gcc/tree-vect-loop.c @@ -140,6 +140,8 @@ along with GCC; see the file COPYING3. If not see http://gcc.gnu.org/projects/tree-ssa/vectorization.html */ +static void vect_estimate_min_profitable_iters (loop_vec_info, int *, int *); + /* Function vect_determine_vectorization_factor Determine the vectorization factor (VF). VF is the number of data elements @@ -1287,6 +1289,8 @@ vect_analyze_loop_operations (loop_vec_info loop_vinfo, bool slp) unsigned int th; bool only_slp_in_loop = true, ok; HOST_WIDE_INT max_niter; + HOST_WIDE_INT estimated_niter; + int min_profitable_estimate; if (dump_kind_p (MSG_NOTE)) dump_printf_loc (MSG_NOTE, vect_location, @@ -1490,7 +1494,8 @@ vect_analyze_loop_operations (loop_vec_info loop_vinfo, bool slp) vector stmts depends on VF. */ vect_update_slp_costs_according_to_vf (loop_vinfo); - min_profitable_iters = vect_estimate_min_profitable_iters (loop_vinfo); + vect_estimate_min_profitable_iters (loop_vinfo, &min_profitable_iters, + &min_profitable_estimate); LOOP_VINFO_COST_MODEL_MIN_ITERS (loop_vinfo) = min_profitable_iters; if (min_profitable_iters < 0) @@ -1508,6 +1513,7 @@ vect_analyze_loop_operations (loop_vec_info loop_vinfo, bool slp) min_scalar_loop_bound = ((PARAM_VALUE (PARAM_MIN_VECT_LOOP_BOUND) * vectorization_factor) - 1); + /* Use the cost model only if it is more conservative than user specified threshold. */ @@ -1531,6 +1537,23 @@ vect_analyze_loop_operations (loop_vec_info loop_vinfo, bool slp) return false; } + if ((estimated_niter = estimated_stmt_executions_int (loop)) != -1 + && ((unsigned HOST_WIDE_INT) estimated_niter + <= MAX (th, (unsigned)min_profitable_estimate))) + { + if (dump_kind_p (MSG_MISSED_OPTIMIZATION)) + dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location, + "not vectorized: estimated iteration count too " + "small."); + if (dump_kind_p (MSG_NOTE)) + dump_printf_loc (MSG_NOTE, vect_location, + "not vectorized: estimated iteration count smaller " + "than specified loop bound parameter or minimum " + "profitable iterations (whichever is more " + "conservative)."); + return false; + } + if (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo) || LOOP_VINFO_INT_NITERS (loop_vinfo) % vectorization_factor != 0 || LOOP_PEELING_FOR_ALIGNMENT (loop_vinfo)) @@ -2603,15 +2626,15 @@ vect_get_known_peeling_cost (loop_vec_info loop_vinfo, int peel_iters_prologue, Return the number of iterations required for the vector version of the loop to be profitable relative to the cost of the scalar version of the - loop. + loop. */ - TODO: Take profile info into account before making vectorization - decisions, if available. */ - -int -vect_estimate_min_profitable_iters (loop_vec_info loop_vinfo) +static void +vect_estimate_min_profitable_iters (loop_vec_info loop_vinfo, + int *ret_min_profitable_niters, + int *ret_min_profitable_estimate) { int min_profitable_iters; + int min_profitable_estimate; int peel_iters_prologue; int peel_iters_epilogue; unsigned vec_inside_cost = 0; @@ -2628,7 +2651,9 @@ vect_estimate_min_profitable_iters (loop_vec_info loop_vinfo) if (!flag_vect_cost_model) { dump_printf_loc (MSG_NOTE, vect_location, "cost model disabled."); - return 0; + *ret_min_profitable_niters = 0; + *ret_min_profitable_estimate = 0; + return; } /* Requires loop versioning tests to handle misalignment. */ @@ -2863,7 +2888,9 @@ vect_estimate_min_profitable_iters (loop_vec_info loop_vinfo) "divided by the scalar iteration cost = %d " "is greater or equal to the vectorization factor = %d.", vec_inside_cost, scalar_single_iter_cost, vf); - return -1; + *ret_min_profitable_niters = -1; + *ret_min_profitable_estimate = -1; + return; } if (dump_kind_p (MSG_NOTE)) @@ -2879,6 +2906,8 @@ vect_estimate_min_profitable_iters (loop_vec_info loop_vinfo) scalar_single_iter_cost); dump_printf (MSG_NOTE, " Scalar outside cost: %d\n", scalar_outside_cost); + dump_printf (MSG_NOTE, " Vector outside cost: %d\n", + vec_outside_cost); dump_printf (MSG_NOTE, " prologue iterations: %d\n", peel_iters_prologue); dump_printf (MSG_NOTE, " epilogue iterations: %d\n", @@ -2898,9 +2927,35 @@ vect_estimate_min_profitable_iters (loop_vec_info loop_vinfo) if (dump_kind_p (MSG_NOTE)) dump_printf_loc (MSG_NOTE, vect_location, - " Profitability threshold = %d\n", min_profitable_iters); + " Runtime profitability threshold = %d\n", min_profitable_iters); + + *ret_min_profitable_niters = min_profitable_iters; + + /* Calculate number of iterations required to make the vector version + profitable, relative to the loop bodies only. + + Non-vectorized variant is SIC * niters and it must win over vector + variant on the expected loop trip count. The following condition must hold true: + SIC * niters > VIC * ((niters-PL_ITERS-EP_ITERS)/VF) + VOC + SOC */ + + if (vec_outside_cost <= 0) + min_profitable_estimate = 1; + else + { + min_profitable_estimate = ((vec_outside_cost + scalar_outside_cost) * vf + - vec_inside_cost * peel_iters_prologue + - vec_inside_cost * peel_iters_epilogue) + / ((scalar_single_iter_cost * vf) + - vec_inside_cost); + } + min_profitable_estimate --; + min_profitable_estimate = MAX (min_profitable_estimate, min_profitable_iters); + if (dump_kind_p (MSG_NOTE)) + dump_printf_loc (MSG_NOTE, vect_location, + " Static estimate profitability threshold = %d\n", + min_profitable_iters); - return min_profitable_iters; + *ret_min_profitable_estimate = min_profitable_estimate; } diff --git a/gcc/tree-vectorizer.h b/gcc/tree-vectorizer.h index 6c99776..5762e00 100644 --- a/gcc/tree-vectorizer.h +++ b/gcc/tree-vectorizer.h @@ -976,7 +976,6 @@ extern bool vectorizable_live_operation (gimple, gimple_stmt_iterator *, extern bool vectorizable_reduction (gimple, gimple_stmt_iterator *, gimple *, slp_tree); extern bool vectorizable_induction (gimple, gimple_stmt_iterator *, gimple *); -extern int vect_estimate_min_profitable_iters (loop_vec_info); extern tree get_initial_def_for_reduction (gimple, tree, tree *); extern int vect_min_worthwhile_factor (enum tree_code); extern int vect_get_known_peeling_cost (loop_vec_info, int, int *, int, |