Hi,
This simple patch computes and preserves loop nest vector for whole distribution
life time. The loop nest will be used multiple times in on-demand data
dependence
computation.
Bootstrap and test on x86_64 and AArch64. Is it OK?
Thanks,
bin
2017-06-07 Bin Cheng <bin.ch...@arm.com>
* tree-loop-distribution.c (loop_nest): New global var.
(build_rdg): Use loop directly, rather than loop nest.
(pg_add_dependence_edges): Remove loop nest parameter. Use global
variable directly.
(distribute_loop): Compute global variable loop nest. Update use.From ea3c198138036676334063226b6c1535e45dd4b2 Mon Sep 17 00:00:00 2001
From: Bin Cheng <binch...@e108451-lin.cambridge.arm.com>
Date: Fri, 9 Jun 2017 11:56:28 +0100
Subject: [PATCH 06/14] loop-nest-20170607.txt
---
gcc/tree-loop-distribution.c | 45 +++++++++++++++++++++++++++-----------------
1 file changed, 28 insertions(+), 17 deletions(-)
diff --git a/gcc/tree-loop-distribution.c b/gcc/tree-loop-distribution.c
index ce6db66..e1f5bce 100644
--- a/gcc/tree-loop-distribution.c
+++ b/gcc/tree-loop-distribution.c
@@ -66,6 +66,9 @@ along with GCC; see the file COPYING3. If not see
#include "tree-vectorizer.h"
+/* The loop (nest) to be distributed. */
+static vec<loop_p> *loop_nest;
+
/* A Reduced Dependence Graph (RDG) vertex representing a statement. */
struct rdg_vertex
{
@@ -454,22 +457,22 @@ free_rdg (struct graph *rdg)
free_graph (rdg);
}
-/* Build the Reduced Dependence Graph (RDG) with one vertex per
- statement of the loop nest LOOP_NEST, and one edge per data dependence or
- scalar dependence. */
+/* Build the Reduced Dependence Graph (RDG) with one vertex per statement of
+ LOOP, and one edge per flow dependence or control dependence from control
+ dependence CD. */
static struct graph *
-build_rdg (vec<loop_p> loop_nest, control_dependences *cd)
+build_rdg (struct loop *loop, control_dependences *cd)
{
struct graph *rdg;
vec<data_reference_p> datarefs;
/* Create the RDG vertices from the stmts of the loop nest. */
auto_vec<gimple *, 10> stmts;
- stmts_from_loop (loop_nest[0], &stmts);
+ stmts_from_loop (loop, &stmts);
rdg = new_graph (stmts.length ());
datarefs.create (10);
- if (!create_rdg_vertices (rdg, stmts, loop_nest[0], &datarefs))
+ if (!create_rdg_vertices (rdg, stmts, loop, &datarefs))
{
datarefs.release ();
free_rdg (rdg);
@@ -479,7 +482,7 @@ build_rdg (vec<loop_p> loop_nest, control_dependences *cd)
create_rdg_flow_edges (rdg);
if (cd)
- create_rdg_cd_edges (rdg, cd, loop_nest[0]);
+ create_rdg_cd_edges (rdg, cd, loop);
datarefs.release ();
@@ -1421,7 +1424,7 @@ partition_contains_all_rw (struct graph *rdg,
and DRS2 and modify and return DIR according to that. */
static int
-pg_add_dependence_edges (struct graph *rdg, vec<loop_p> loops, int dir,
+pg_add_dependence_edges (struct graph *rdg, int dir,
vec<data_reference_p> drs1,
vec<data_reference_p> drs2)
{
@@ -1442,8 +1445,8 @@ pg_add_dependence_edges (struct graph *rdg, vec<loop_p>
loops, int dir,
std::swap (dr1, dr2);
this_dir = -this_dir;
}
- ddr = initialize_data_dependence_relation (dr1, dr2, loops);
- compute_affine_dependence (ddr, loops[0]);
+ ddr = initialize_data_dependence_relation (dr1, dr2, *loop_nest);
+ compute_affine_dependence (ddr, (*loop_nest)[0]);
if (DDR_ARE_DEPENDENT (ddr) == chrec_dont_know)
this_dir = 2;
else if (DDR_ARE_DEPENDENT (ddr) == NULL_TREE)
@@ -1511,11 +1514,15 @@ distribute_loop (struct loop *loop, vec<gimple *> stmts,
*destroy_p = false;
*nb_calls = 0;
- auto_vec<loop_p, 3> loop_nest;
- if (!find_loop_nest (loop, &loop_nest))
- return 0;
+ loop_nest = new vec<loop_p> ();
+ if (!find_loop_nest (loop, loop_nest))
+ {
+ loop_nest->release ();
+ delete loop_nest;
+ return 0;
+ }
- rdg = build_rdg (loop_nest, cd);
+ rdg = build_rdg (loop, cd);
if (!rdg)
{
if (dump_file && (dump_flags & TDF_DETAILS))
@@ -1523,6 +1530,8 @@ distribute_loop (struct loop *loop, vec<gimple *> stmts,
"Loop %d not distributed: failed to build the RDG.\n",
loop->num);
+ loop_nest->release ();
+ delete loop_nest;
return 0;
}
@@ -1646,15 +1655,15 @@ distribute_loop (struct loop *loop, vec<gimple *> stmts,
/* dependence direction - 0 is no dependence, -1 is back,
1 is forth, 2 is both (we can stop then, merging will occur). */
int dir = 0;
- dir = pg_add_dependence_edges (rdg, loop_nest, dir,
+ dir = pg_add_dependence_edges (rdg, dir,
PGDATA(i)->writes,
PGDATA(j)->reads);
if (dir != 2)
- dir = pg_add_dependence_edges (rdg, loop_nest, dir,
+ dir = pg_add_dependence_edges (rdg, dir,
PGDATA(i)->reads,
PGDATA(j)->writes);
if (dir != 2)
- dir = pg_add_dependence_edges (rdg, loop_nest, dir,
+ dir = pg_add_dependence_edges (rdg, dir,
PGDATA(i)->writes,
PGDATA(j)->writes);
if (dir == 1 || dir == 2)
@@ -1730,6 +1739,8 @@ distribute_loop (struct loop *loop, vec<gimple *> stmts,
}
ldist_done:
+ loop_nest->release ();
+ delete loop_nest;
FOR_EACH_VEC_ELT (partitions, i, partition)
partition_free (partition);
--
1.9.1
