Remove limit_scops

This patch removes graphite-scop-detection.c:limit_scops function and fix
related issues arising because of that. The functionality limit_scop was added
as an intermediate step to discard the loops which graphite could not
handle. Removing limit_scop required handling of different cases of loops and
surrounding code.  The scop is now larger so most test cases required 'number of
scops detected' to be fixed. By increasing the size of scop we can now optimize
loops which are 'siblings' of each other. This could enable loop fusion on a
number of loops. Since in the graphite framework we mostly want to opimize
loop-nests/adjacent-loops, we now discard scops with less than 2 loops. We
also discard scops without any data references.

Essentially:
 - Remove limite_scops.
 - Only select scops when there are at least two loops (loop nest or, side by side).
 - Discard loops without data-refs.
 - Fix test cases.

Passes bootstrap and reg-test.

gcc/ChangeLog:

2015-09-02  Aditya Kumar  <hiraditya@msn.com>
            Sebastian Pop  <s.pop@samsung.com>

        * graphite-isl-ast-to-gimple.c (gcc_expression_from_isl_ast_expr_id):
        Return the parameter if it was saved in corresponding
        parameter_rename_map of the region.
        (copy_def): Copy def from sese region to the newly created region.
        (copy_internal_parameters): Copy all the internal parameters defined
        within a region to the newly created region.
        (graphite_regenerate_ast_isl): Copy parameters to the new region before
        translating isl to gimple.
        * graphite-scop-detection.c (graphite_can_represent_loop): Bail out if
          the loop-nest does not have any data-references.
        (build_graphite_scops): Create a scop only when there is at least one
        loop inside it.
        (contains_only_close_phi_nodes): Deleted.
        (print_graphite_scop_statistics): Deleted
        (print_graphite_statistics): Deleted
        (limit_scops): Deleted.
        (build_scops): Removed call to limit_scops.
        * sese.c (new_sese): Construct.
        (free_sese): Destruct.
        (sese_add_exit_phis_edge): update_stmt after exit phi edge has been
        added.
        (set_rename): Pass sese region so that parameters inside the region can
        be added to its parameter_rename_map.
        (rename_uses): Pass sese region.
        (graphite_copy_stmts_from_block): Do not copy parameters that have been
        generated in the header of the scop. For each SSA_NAME in the
        parameter_rename_map rename its usage.
        (invariant_in_sese_p_rec): Return false if tree t is defined outside
        sese region.
        (scalar_evolution_in_region): If the tree t is invariant just return t.
        * sese.h: Added a parameter renamne map (parameter_rename_map_t) to
          struct sese to keep track of all the parameters which need renaming.
        * tree-data-ref.c (loop_nest_has_data_refs): Check if a loop nest has
          any data-refs.
        * tree-data-ref.h: Declaration of loop_nest_has_data_refs.

gcc/testsuite/ChangeLog:

2015-09-02  Aditya Kumar  <hiraditya@msn.com>
            Sebastian Pop  <s.pop@samsung.com>

        * gcc.dg/graphite/block-0.c: Modifed test case to match current output.
        * gcc.dg/graphite/block-1.c: Same.
        * gcc.dg/graphite/block-5.c: Same.
        * gcc.dg/graphite/block-6.c: Same.
        * gcc.dg/graphite/interchange-1.c: Same.
        * gcc.dg/graphite/interchange-10.c: Same.
        * gcc.dg/graphite/interchange-11.c: Same.
        * gcc.dg/graphite/interchange-13.c: Same.
        * gcc.dg/graphite/interchange-14.c: Same.
        * gcc.dg/graphite/interchange-3.c: Same.
        * gcc.dg/graphite/interchange-4.c: Same.
        * gcc.dg/graphite/interchange-7.c: Same.
        * gcc.dg/graphite/interchange-8.c: Same.
        * gcc.dg/graphite/interchange-9.c: Same.
        * gcc.dg/graphite/isl-codegen-loop-dumping.c: Same.
        * gcc.dg/graphite/pr35356-1.c (foo): Same.
        * gcc.dg/graphite/pr37485.c: Same.
        * gcc.dg/graphite/scop-0.c (int toto): Same.
        * gcc.dg/graphite/scop-1.c: Same.
        * gcc.dg/graphite/scop-10.c: Same.
        * gcc.dg/graphite/scop-11.c: Same.
        * gcc.dg/graphite/scop-12.c: Same.
        * gcc.dg/graphite/scop-13.c: Same.
        * gcc.dg/graphite/scop-16.c: Same.
        * gcc.dg/graphite/scop-17.c: Same.
        * gcc.dg/graphite/scop-18.c: Same.
        * gcc.dg/graphite/scop-2.c: Same.
        * gcc.dg/graphite/scop-21.c (int test): Same.
        * gcc.dg/graphite/scop-22.c (void foo): Same.
        * gcc.dg/graphite/scop-4.c: Same.
        * gcc.dg/graphite/scop-5.c: Same.
        * gcc.dg/graphite/scop-6.c: Same.
        * gcc.dg/graphite/scop-7.c: Same.
        * gcc.dg/graphite/scop-8.c: Same.
        * gcc.dg/graphite/scop-9.c: Same.
        * gcc.dg/graphite/scop-mvt.c (void mvt): Introduced dependency so that
          data-refs remain inside the inner loop.
        * gcc.dg/graphite/uns-block-1.c: Modifed test case to match o/p.
        * gcc.dg/graphite/uns-interchange-14.c: Same.
        * gcc.dg/graphite/uns-interchange-9.c: Same.
        * gfortran.dg/graphite/interchange-3.f90

libgomp/ChangeLog:

2015-09-04  Aditya Kumar  <hiraditya@msn.com>
            Sebastian Pop  <s.pop@samsung.com>

        * testsuite/libgomp.graphite/bounds.c (int foo): Modifed test case to
          match o/p.
        * testsuite/libgomp.graphite/force-parallel-1.c (void parloop): Same.
        * testsuite/libgomp.graphite/force-parallel-4.c: Same.
        * testsuite/libgomp.graphite/force-parallel-5.c: Same.
        * testsuite/libgomp.graphite/force-parallel-7.c: Same.
        * testsuite/libgomp.graphite/force-parallel-8.c: Same.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@227567 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 77 insertions, 4 deletions

diff --git a/gcc/graphite-isl-ast-to-gimple.c b/gcc/graphite-isl-ast-to-gimple.c
index 5434bfdeb6f..a8c99c3faad 100644
--- a/gcc/graphite-isl-ast-to-gimple.c
+++ b/gcc/graphite-isl-ast-to-gimple.c
@@ -57,7 +57,9 @@ extern "C" {
 #include "tree-ssa-loop-manip.h"
 #include "tree-scalar-evolution.h"
 #include "gimple-ssa.h"
+#include "tree-phinodes.h"
 #include "tree-into-ssa.h"
+#include "ssa-iterators.h"
 #include <map>
 #include "graphite-isl-ast-to-gimple.h"
 
@@ -286,7 +288,12 @@ gcc_expression_from_isl_ast_expr_id (tree type,
   gcc_assert (res != ip.end () &&
 	      "Could not map isl_id to tree expression");
   isl_ast_expr_free (expr_id);
-  return fold_convert (type, res->second);
+  tree t = res->second;
+  tree *val = region->parameter_rename_map->get(t);
+
+  if (!val)
+   val = &t;
+  return fold_convert (type, *val);
 }
 
 /* Converts an isl_ast_expr_int expression E to a GCC expression tree of
@@ -1063,6 +1070,69 @@ scop_to_isl_ast (scop_p scop, ivs_params &ip)
   return ast_isl;
 }
 
+/* Copy def from sese REGION to the newly created TO_REGION. TR is defined by
+   DEF_STMT. GSI points to entry basic block of the TO_REGION.  */
+
+static void
+copy_def(tree tr, gimple def_stmt, sese region, sese to_region, gimple_stmt_iterator *gsi)
+{
+  if (!defined_in_sese_p (tr, region))
+    return;
+  ssa_op_iter iter;
+  use_operand_p use_p;
+
+  FOR_EACH_SSA_USE_OPERAND (use_p, def_stmt, iter, SSA_OP_USE)
+    {
+      tree use_tr = USE_FROM_PTR (use_p);
+
+      /* Do not copy parameters that have been generated in the header of the
+	 scop.  */
+      if (region->parameter_rename_map->get(use_tr))
+	continue;
+
+      gimple def_of_use = SSA_NAME_DEF_STMT (use_tr);
+      if (!def_of_use)
+	continue;
+
+      copy_def (use_tr, def_of_use, region, to_region, gsi);
+    }
+
+  gimple copy = gimple_copy (def_stmt);
+  gsi_insert_after (gsi, copy, GSI_NEW_STMT);
+
+  /* Create new names for all the definitions created by COPY and
+     add replacement mappings for each new name.  */
+  def_operand_p def_p;
+  ssa_op_iter op_iter;
+  FOR_EACH_SSA_DEF_OPERAND (def_p, copy, op_iter, SSA_OP_ALL_DEFS)
+    {
+      tree old_name = DEF_FROM_PTR (def_p);
+      tree new_name = create_new_def_for (old_name, copy, def_p);
+      region->parameter_rename_map->put(old_name, new_name);
+    }
+
+  update_stmt (copy);
+}
+
+static void
+copy_internal_parameters(sese region, sese to_region)
+{
+  /* For all the parameters which definitino is in the if_region->false_region,
+     insert code on true_region (if_region->true_region->entry). */
+
+  int i;
+  tree tr;
+  gimple_stmt_iterator gsi = gsi_start_bb(to_region->entry->dest);
+
+  FOR_EACH_VEC_ELT (region->params, i, tr)
+    {
+      // If def is not in region.
+      gimple def_stmt = SSA_NAME_DEF_STMT (tr);
+      if (def_stmt)
+	copy_def (tr, def_stmt, region, to_region, &gsi);
+    }
+}
+
 /* GIMPLE Loop Generator: generates loops from STMT in GIMPLE form for
    the given SCOP.  Return true if code generation succeeded.
 
@@ -1102,10 +1172,13 @@ graphite_regenerate_ast_isl (scop_p scop)
 
   context_loop = SESE_ENTRY (region)->src->loop_father;
 
-  translate_isl_ast_to_gimple t (region);
+  /* Copy all the parameters which are defined in the region.  */
+  copy_internal_parameters(if_region->false_region, if_region->true_region);
 
-  t.translate_isl_ast (context_loop, root_node, if_region->true_region->entry,
-		     ip);
+  translate_isl_ast_to_gimple t(region);
+  edge e = single_succ_edge (if_region->true_region->entry->dest);
+  split_edge (e);
+  t.translate_isl_ast (context_loop, root_node, e, ip);
 
   mark_virtual_operands_for_renaming (cfun);
   update_ssa (TODO_update_ssa);