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, 24 insertions, 3 deletions

diff --git a/gcc/gimple-range.cc b/gcc/gimple-range.cc
index 73398dd..04075a9 100644
--- a/gcc/gimple-range.cc
+++ b/gcc/gimple-range.cc
@@ -35,6 +35,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "tree-scalar-evolution.h"
 #include "gimple-range.h"
 #include "gimple-fold.h"
+#include "gimple-walk.h"
 
 gimple_ranger::gimple_ranger () :
 	non_executable_edge_flag (cfun),
@@ -117,8 +118,10 @@ gimple_ranger::range_of_expr (irange &r, tree expr, gimple *stmt)
       // If name is defined in this block, try to get an range from S.
       if (def_stmt && gimple_bb (def_stmt) == bb)
 	{
-	  range_of_stmt (r, def_stmt, expr);
-	  m_cache.m_non_null.adjust_range (r, expr, bb, true);
+	  // Check for a definition override from a block walk.
+	  if (!POINTER_TYPE_P (TREE_TYPE (expr))
+	      || !m_cache.block_range (r, bb, expr, false))
+	    range_of_stmt (r, def_stmt, expr);
 	}
       // Otherwise OP comes from outside this block, use range on entry.
       else
@@ -151,7 +154,12 @@ gimple_ranger::range_on_entry (irange &r, basic_block bb, tree name)
   if (m_cache.block_range (entry_range, bb, name))
     r.intersect (entry_range);
 
-  m_cache.m_non_null.adjust_range (r, name, bb, true);
+  if (dom_info_available_p (CDI_DOMINATORS))
+    {
+      basic_block dom_bb = get_immediate_dominator (CDI_DOMINATORS, bb);
+      if (dom_bb)
+	m_cache.m_non_null.adjust_range (r, name, dom_bb, true);
+    }
 
   if (idx)
     tracer.trailer (idx, "range_on_entry", true, name, r);
@@ -227,6 +235,9 @@ gimple_ranger::range_on_edge (irange &r, edge e, tree name)
   else
     {
       range_on_exit (r, e->src, name);
+      // If this is not an abnormal edge, check for a non-null exit .
+      if ((e->flags & (EDGE_EH | EDGE_ABNORMAL)) == 0)
+	m_cache.m_non_null.adjust_range (r, name, e->src, false);
       gcc_checking_assert  (r.undefined_p ()
 			    || range_compatible_p (r.type(), TREE_TYPE (name)));
 
@@ -436,6 +447,16 @@ gimple_ranger::fold_stmt (gimple_stmt_iterator *gsi, tree (*valueize) (tree))
   return ret;
 }
 
+// Called during dominator walks to register any side effects that take effect
+// from this point forward.  Current release is only for tracking non-null
+// within a block.
+
+void
+gimple_ranger::register_side_effects (gimple *s)
+{
+  m_cache.block_apply_nonnull (s);
+}
+
 // This routine will export whatever global ranges are known to GCC
 // SSA_RANGE_NAME_INFO and SSA_NAME_PTR_INFO fields.