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, 8 insertions, 9 deletions

diff --git a/gcc/tree-data-ref.c b/gcc/tree-data-ref.c
index 19cceb8..559a8e4 100644
--- a/gcc/tree-data-ref.c
+++ b/gcc/tree-data-ref.c
@@ -957,15 +957,14 @@ access_fn_component_p (tree op)
 }
 
 /* Determines the base object and the list of indices of memory reference
-   DR, analyzed in LOOP and instantiated in loop nest NEST.  */
+   DR, analyzed in LOOP and instantiated before NEST.  */
 
 static void
-dr_analyze_indices (struct data_reference *dr, loop_p nest, loop_p loop)
+dr_analyze_indices (struct data_reference *dr, edge nest, loop_p loop)
 {
   vec<tree> access_fns = vNULL;
   tree ref, op;
   tree base, off, access_fn;
-  basic_block before_loop;
 
   /* If analyzing a basic-block there are no indices to analyze
      and thus no access functions.  */
@@ -977,7 +976,6 @@ dr_analyze_indices (struct data_reference *dr, loop_p nest, loop_p loop)
     }
 
   ref = DR_REF (dr);
-  before_loop = block_before_loop (nest);
 
   /* REALPART_EXPR and IMAGPART_EXPR can be handled like accesses
      into a two element array with a constant index.  The base is
@@ -1002,7 +1000,7 @@ dr_analyze_indices (struct data_reference *dr, loop_p nest, loop_p loop)
 	{
 	  op = TREE_OPERAND (ref, 1);
 	  access_fn = analyze_scalar_evolution (loop, op);
-	  access_fn = instantiate_scev (before_loop, loop, access_fn);
+	  access_fn = instantiate_scev (nest, loop, access_fn);
 	  access_fns.safe_push (access_fn);
 	}
       else if (TREE_CODE (ref) == COMPONENT_REF
@@ -1034,7 +1032,7 @@ dr_analyze_indices (struct data_reference *dr, loop_p nest, loop_p loop)
     {
       op = TREE_OPERAND (ref, 0);
       access_fn = analyze_scalar_evolution (loop, op);
-      access_fn = instantiate_scev (before_loop, loop, access_fn);
+      access_fn = instantiate_scev (nest, loop, access_fn);
       if (TREE_CODE (access_fn) == POLYNOMIAL_CHREC)
 	{
 	  tree orig_type;
@@ -1139,7 +1137,7 @@ free_data_ref (data_reference_p dr)
    in which the data reference should be analyzed.  */
 
 struct data_reference *
-create_data_ref (loop_p nest, loop_p loop, tree memref, gimple *stmt,
+create_data_ref (edge nest, loop_p loop, tree memref, gimple *stmt,
 		 bool is_read, bool is_conditional_in_stmt)
 {
   struct data_reference *dr;
@@ -4970,7 +4968,8 @@ find_data_references_in_stmt (struct loop *nest, gimple *stmt,
 
   FOR_EACH_VEC_ELT (references, i, ref)
     {
-      dr = create_data_ref (nest, loop_containing_stmt (stmt), ref->ref,
+      dr = create_data_ref (nest ? loop_preheader_edge (nest) : NULL,
+			    loop_containing_stmt (stmt), ref->ref,
 			    stmt, ref->is_read, ref->is_conditional_in_stmt);
       gcc_assert (dr != NULL);
       datarefs->safe_push (dr);
@@ -4986,7 +4985,7 @@ find_data_references_in_stmt (struct loop *nest, gimple *stmt,
    should be analyzed.  */
 
 bool
-graphite_find_data_references_in_stmt (loop_p nest, loop_p loop, gimple *stmt,
+graphite_find_data_references_in_stmt (edge nest, loop_p loop, gimple *stmt,
 				       vec<data_reference_p> *datarefs)
 {
   unsigned i;