[gcc r13-2044] Simplify range_on_path_entry

[gcc r13-2044] Simplify range_on_path_entry

[Richard Biener]

https://gcc.gnu.org/g:e236d671d460dd47262accdea2e9d1d80820ae88

commit r13-2044-ge236d671d460dd47262accdea2e9d1d80820ae88
Author: Richard Biener <rguenther@suse.de>
Date:   Mon Aug 15 13:03:54 2022 +0200

    Simplify range_on_path_entry
    
    I've noticed that range_on_path_entry does mightly complicated things
    that don't make sense to me and the commentary might just be
    out of date.  For the sake of it I replaced it with range_on_entry
    and statistics show we thread _more_ jumps with that, so better
    not do magic there.
    
            * gimple-range-path.cc (range_on_path_entry): Just
            call range_on_entry.

Diff:
---
 gcc/gimple-range-path.cc | 33 +--------------------------------
 1 file changed, 1 insertion(+), 32 deletions(-)

diff --git a/gcc/gimple-range-path.cc b/gcc/gimple-range-path.cc
index 5ff2c733b4e..78146f5683e 100644
--- a/gcc/gimple-range-path.cc
+++ b/gcc/gimple-range-path.cc
@@ -153,38 +153,7 @@ path_range_query::range_on_path_entry (vrange &r, tree name)
 {
   gcc_checking_assert (defined_outside_path (name));
   basic_block entry = entry_bb ();
-
-  // Prefer to use range_of_expr if we have a statement to look at,
-  // since it has better caching than range_on_edge.
-  gimple *last = last_stmt (entry);
-  if (last)
-    {
-      if (m_ranger->range_of_expr (r, name, last))
-	return;
-      gcc_unreachable ();
-    }
-
-  // If we have no statement, look at all the incoming ranges to the
-  // block.  This can happen when we're querying a block with only an
-  // outgoing edge (no statement but the fall through edge), but for
-  // which we can determine a range on entry to the block.
-  Value_Range tmp (TREE_TYPE (name));
-  bool changed = false;
-  r.set_undefined ();
-  for (unsigned i = 0; i < EDGE_COUNT (entry->preds); ++i)
-    {
-      edge e = EDGE_PRED (entry, i);
-      if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
-	  && m_ranger->range_on_edge (tmp, e, name))
-	{
-	  r.union_ (tmp);
-	  changed = true;
-	}
-    }
-
-  // Make sure we don't return UNDEFINED by mistake.
-  if (!changed)
-    r.set_varying (TREE_TYPE (name));
+  m_ranger->range_on_entry (r, entry, name);
 }
 
 // Return the range of NAME at the end of the path being analyzed.