Register non-null side effects properly.

This patch adjusts uses of nonnull to accurately reflect "somewhere in block".
It also adds the ability to register statement side effects within a block
for ranger which will apply for the rest of the block.

	PR tree-optimization/104288
	gcc/
	* gimple-range-cache.cc (non_null_ref::set_nonnull): New.
	(non_null_ref::adjust_range): Move to header.
	(ranger_cache::range_of_def): Don't check non-null.
	(ranger_cache::entry_range): Don't check non-null.
	(ranger_cache::range_on_edge): Check for nonnull on normal edges.
	(ranger_cache::update_to_nonnull): New.
	(non_null_loadstore): New.
	(ranger_cache::block_apply_nonnull): New.
	* gimple-range-cache.h (class non_null_ref): Update prototypes.
	(non_null_ref::adjust_range): Move to here and inline.
	(class ranger_cache): Update prototypes.
	* gimple-range-path.cc (path_range_query::range_defined_in_block): Do
	not search dominators.
	(path_range_query::adjust_for_non_null_uses): Ditto.
	* gimple-range.cc (gimple_ranger::range_of_expr): Check on-entry for
	def overrides.  Do not check nonnull.
	(gimple_ranger::range_on_entry): Check dominators for nonnull.
	(gimple_ranger::range_on_edge): Check for nonnull on normal edges..
	(gimple_ranger::register_side_effects): New.
	* gimple-range.h (gimple_ranger::register_side_effects): New.
	* tree-vrp.cc (rvrp_folder::fold_stmt): Call register_side_effects.

	gcc/testsuite/
	* gcc.dg/pr104288.c: New.

1 files changed, 31 insertions, 0 deletions

diff --git a/gcc/gimple-range-cache.h b/gcc/gimple-range-cache.h
index b54b688..589b649 100644
--- a/gcc/gimple-range-cache.h
+++ b/gcc/gimple-range-cache.h
@@ -36,12 +36,41 @@ public:
   bool non_null_deref_p (tree name, basic_block bb, bool search_dom = true);
   bool adjust_range (irange &r, tree name, basic_block bb,
 		     bool search_dom = true);
+  bool set_nonnull (basic_block bb, tree name);
 private:
   vec <bitmap> m_nn;
   void process_name (tree name);
   bitmap_obstack m_bitmaps;
 };
 
+// If NAME has a non-null dereference in block BB, adjust R with the
+// non-zero information from non_null_deref_p, and return TRUE.  If
+// SEARCH_DOM is true, non_null_deref_p should search the dominator tree.
+
+inline bool
+non_null_ref::adjust_range (irange &r, tree name, basic_block bb,
+			    bool search_dom)
+{
+  // Non-call exceptions mean we could throw in the middle of the
+  // block, so just punt on those for now.
+  if (cfun->can_throw_non_call_exceptions)
+    return false;
+  // We only care about the null / non-null property of pointers.
+  if (!POINTER_TYPE_P (TREE_TYPE (name)))
+    return false;
+  if (r.undefined_p () || r.lower_bound () != 0 || r.upper_bound () == 0)
+    return false;
+  // Check if pointers have any non-null dereferences.
+  if (non_null_deref_p (name, bb, search_dom))
+    {
+      // Remove zero from the range.
+      unsigned prec = TYPE_PRECISION (TREE_TYPE (name));
+      r.intersect (wi::one (prec), wi::max_value (prec, UNSIGNED));
+      return true;
+    }
+  return false;
+}
+
 // This class manages a vector of pointers to ssa_block ranges.  It
 // provides the basis for the "range on entry" cache for all
 // SSA names.
@@ -106,6 +135,8 @@ public:
 
   void propagate_updated_value (tree name, basic_block bb);
 
+  void block_apply_nonnull (gimple *s);
+  void update_to_nonnull (basic_block bb, tree name);
   non_null_ref m_non_null;
   gori_compute m_gori;