Add transitive inferred range processing.

Rewalk statements at the end of a block to see if any inferred ranges
affect earlier calculations and register those as inferred ranges.

	gcc/
	PR tree-optimization/104530
	* gimple-range-cache.cc (ranger_cache::register_inferred_value):
	New.  Split from:
	(ranger_cache::apply_inferred_ranges): Move setting cache to
	separate function.
	* gimple-range-cache.h (register_inferred_value): New prototype.
	* gimple-range-infer.cc (infer_range_manager::has_range_p): New.
	* gimple-range-infer.h (has_range_p): New prototype.
	* gimple-range.cc (register_transitive_inferred_ranges): New.
	* gimple-range.h (register_transitive_inferred_ranges): New proto.
	* tree-vrp.cc (rvrp_folder::fold_stmt): Check for transitive inferred
	ranges at the end of the block before folding final stmt.

	gcc/testsuite/
	* gcc.dg/pr104530.c: New.

1 files changed, 9 insertions, 0 deletions

diff --git a/gcc/tree-vrp.cc b/gcc/tree-vrp.cc
index 39f7eb7..3393c73 100644
--- a/gcc/tree-vrp.cc
+++ b/gcc/tree-vrp.cc
@@ -4501,6 +4501,15 @@ public:
 
   bool fold_stmt (gimple_stmt_iterator *gsi) override
   {
+    gimple *s = gsi_stmt (*gsi);
+    // If this is a block ending condition, and there are inferred ranges,
+    // reparse the block to see if there are any transitive inferred ranges.
+    if (is_a<gcond *> (s))
+      {
+	basic_block bb = gimple_bb (s);
+	if (bb && s == gimple_outgoing_range_stmt_p (bb))
+	  m_ranger->register_transitive_inferred_ranges (bb);
+      }
     bool ret = m_simplifier.simplify (gsi);
     if (!ret)
       ret = m_ranger->fold_stmt (gsi, follow_single_use_edges);