[gcc r14-75] Remove special-cased edges when solving copies

[Richard Biener <rguenth@gcc.gnu.org>]

https://gcc.gnu.org/g:6702fdcdf8b8c8ed27954972bb10b2464f4912fb

commit r14-75-g6702fdcdf8b8c8ed27954972bb10b2464f4912fb
Author: Richard Biener <rguenther@suse.de>
Date:   Wed Mar 15 08:46:04 2023 +0100

    Remove special-cased edges when solving copies
    
    The following makes sure to remove the copy edges we ignore or
    need to special-case only once.
    
            * tree-ssa-structalias.cc (solve_graph): Remove self-copy
            edges, remove edges from escaped after special-casing them.

Diff:
---
 gcc/tree-ssa-structalias.cc | 25 ++++++++++++++-----------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/gcc/tree-ssa-structalias.cc b/gcc/tree-ssa-structalias.cc
index 4f350bfbfc0..39c342fae41 100644
--- a/gcc/tree-ssa-structalias.cc
+++ b/gcc/tree-ssa-structalias.cc
@@ -2873,19 +2873,22 @@ solve_graph (constraint_graph_t graph)
 			}
 		      /* Don't try to propagate to ourselves.  */
 		      if (to == i)
-			continue;
-
-		      bitmap tmp = get_varinfo (to)->solution;
-		      bool flag = false;
-
-		      /* If we propagate from ESCAPED use ESCAPED as
-		         placeholder.  */
+			{
+			  to_remove = j;
+			  continue;
+			}
+		      /* Early node unification can lead to edges from
+			 escaped - remove them.  */
 		      if (i == eff_escaped_id)
-			flag = bitmap_set_bit (tmp, escaped_id);
-		      else
-			flag = bitmap_ior_into (tmp, pts);
+			{
+			  to_remove = j;
+			  if (bitmap_set_bit (get_varinfo (to)->solution,
+					      escaped_id))
+			    bitmap_set_bit (changed, to);
+			  continue;
+			}
 
-		      if (flag)
+		      if (bitmap_ior_into (get_varinfo (to)->solution, pts))
 			bitmap_set_bit (changed, to);
 		    }
 		  if (to_remove != ~0U)