re PR tree-optimization/82451 ([GRAPHITE] codegen error in get_rename_from_scev)

2017-10-13  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/82451
	Revert
	2017-10-02  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/82355
	* graphite-isl-ast-to-gimple.c (build_iv_mapping): Also build
	a mapping for the enclosing loop but avoid generating one for
	the loop tree root.
	(copy_bb_and_scalar_dependences): Remove premature codegen
	error on PHIs in blocks duplicated into multiple places.
	* graphite-scop-detection.c
	(scop_detection::stmt_has_simple_data_refs_p): For a loop not
	in the region use it as loop and nest to analyze the DR in.
	(try_generate_gimple_bb): Likewise.
	* graphite-sese-to-poly.c (extract_affine_chrec): Adjust.
	(add_loop_constraints): For blocks in a loop not in the region
	create a dimension with a single iteration.
	* sese.h (gbb_loop_at_index): Remove assert.

	* cfgloop.c (loop_preheader_edge): For the loop tree root
	return the single successor of the entry block.
	* graphite-isl-ast-to-gimple.c (graphite_regenerate_ast_isl):
	Reset the SCEV hashtable and niters.
	* graphite-scop-detection.c
	(scop_detection::graphite_can_represent_scev): Add SCOP parameter,
	assert that we only have POLYNOMIAL_CHREC that vary in loops
	contained in the region.
	(scop_detection::graphite_can_represent_expr): Adjust.
	(scop_detection::stmt_has_simple_data_refs_p): For loops
	not in the region set loop to NULL.  The nest is now the
	entry edge to the region.
	(try_generate_gimple_bb): Likewise.
	* sese.c (scalar_evolution_in_region): Adjust for
	instantiate_scev change.
	* tree-data-ref.h (graphite_find_data_references_in_stmt):
	Make nest parameter the edge into the region.
	(create_data_ref): Likewise.
	* tree-data-ref.c (dr_analyze_indices): Make nest parameter an
	entry edge into a region and adjust instantiate_scev calls.
	(create_data_ref): Likewise.
	(graphite_find_data_references_in_stmt): Likewise.
	(find_data_references_in_stmt): Pass the loop preheader edge
	from the nest argument.
	* tree-scalar-evolution.h (instantiate_scev): Make instantiate_below
	parameter the edge into the region.
	(instantiate_parameters): Use the loop preheader edge as entry.
	* tree-scalar-evolution.c (analyze_scalar_evolution): Handle
	NULL loop.
	(get_instantiated_value_entry): Make instantiate_below parameter
	the edge into the region.
	(instantiate_scev_name): Likewise.  Adjust dominance checks,
	when we cannot use loop-based instantiation instantiate by
	walking use-def chains.
	(instantiate_scev_poly): Adjust.
	(instantiate_scev_binary): Likewise.
	(instantiate_scev_convert): Likewise.
	(instantiate_scev_not): Likewise.
	(instantiate_array_ref): Remove.
	(instantiate_scev_3): Likewise.
	(instantiate_scev_2): Likewise.
	(instantiate_scev_1): Likewise.
	(instantiate_scev_r): Do not blindly handle N-operand trees.
	Do not instantiate array-refs.  Handle all constants and invariants.
	(instantiate_scev): Make instantiate_below parameter
	the edge into the region.
	(resolve_mixers): Use the loop preheader edge for the region
	parameter to instantiate_scev_r.
	* tree-ssa-loop-prefetch.c (determine_loop_nest_reuse): Adjust.

	* gcc.dg/graphite/pr82451.c: New testcase.
	* gfortran.dg/graphite/id-27.f90: Likewise.
	* gfortran.dg/graphite/pr82451.f: Likewise.

From-SVN: r253707

1 files changed, 5 insertions, 20 deletions

diff --git a/gcc/graphite-sese-to-poly.c b/gcc/graphite-sese-to-poly.c
index 50b6fe8dbb2..ed6cbeccca1 100644
--- a/gcc/graphite-sese-to-poly.c
+++ b/gcc/graphite-sese-to-poly.c
@@ -86,7 +86,7 @@ extract_affine_chrec (scop_p s, tree e, __isl_take isl_space *space)
   isl_pw_aff *lhs = extract_affine (s, CHREC_LEFT (e), isl_space_copy (space));
   isl_pw_aff *rhs = extract_affine (s, CHREC_RIGHT (e), isl_space_copy (space));
   isl_local_space *ls = isl_local_space_from_space (space);
-  unsigned pos = sese_loop_depth (s->scop_info->region, get_chrec_loop (e));
+  unsigned pos = sese_loop_depth (s->scop_info->region, get_chrec_loop (e)) - 1;
   isl_aff *loop = isl_aff_set_coefficient_si
     (isl_aff_zero_on_domain (ls), isl_dim_in, pos, 1);
   isl_pw_aff *l = isl_pw_aff_from_aff (loop);
@@ -763,10 +763,10 @@ add_loop_constraints (scop_p scop, __isl_take isl_set *domain, loop_p loop,
     return domain;
   const sese_l &region = scop->scop_info->region;
   if (!loop_in_sese_p (loop, region))
-    ;
-  else
-    /* Recursion all the way up to the context loop.  */
-    domain = add_loop_constraints (scop, domain, loop_outer (loop), context);
+    return domain;
+
+  /* Recursion all the way up to the context loop.  */
+  domain = add_loop_constraints (scop, domain, loop_outer (loop), context);
 
   /* Then, build constraints over the loop in post-order: outer to inner.  */
 
@@ -777,21 +777,6 @@ add_loop_constraints (scop_p scop, __isl_take isl_set *domain, loop_p loop,
   domain = add_iter_domain_dimension (domain, loop, scop);
   isl_space *space = isl_set_get_space (domain);
 
-  if (!loop_in_sese_p (loop, region))
-    {
-      /* 0 == loop_i */
-      isl_local_space *ls = isl_local_space_from_space (space);
-      isl_constraint *c = isl_equality_alloc (ls);
-      c = isl_constraint_set_coefficient_si (c, isl_dim_set, loop_index, 1);
-      if (dump_file)
-	{
-	  fprintf (dump_file, "[sese-to-poly] adding constraint to the domain: ");
-	  print_isl_constraint (dump_file, c);
-	}
-      domain = isl_set_add_constraint (domain, c);
-      return domain;
-    }
-
   /* 0 <= loop_i */
   isl_local_space *ls = isl_local_space_from_space (isl_space_copy (space));
   isl_constraint *c = isl_inequality_alloc (ls);