Hi,
while updating compute_points_to_sets I missed that the code not only
sets the nonlocal/escaped flags but also initializes pt.  With my
previous change if uses_global_memory is false pt is not updated
correctly which may lead to wrong code.

This is fixed by the following patch I comitted to avoid strange
misoptimizations.

Bootstrapped/regtested x86_64-linux and also tested with LTO.

Honza

gcc/ChangeLog:

        PR tree-optimization/102720
        * tree-ssa-structalias.c (compute_points_to_sets): Fix producing
        of call used and clobbered sets.

diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index 6f12a66ee0d..2e6513bb72a 100644
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -7541,17 +7541,18 @@ compute_points_to_sets (void)
              determine_global_memory_access (stmt, NULL,
                                              &reads_global_memory,
                                              &uses_global_memory);
-             if (!uses_global_memory)
-               ;
-             else if ((vi = lookup_call_use_vi (stmt)) != NULL)
+             if ((vi = lookup_call_use_vi (stmt)) != NULL)
                {
                  *pt = find_what_var_points_to (cfun->decl, vi);
                  /* Escaped (and thus nonlocal) variables are always
                     implicitly used by calls.  */
                  /* ???  ESCAPED can be empty even though NONLOCAL
                     always escaped.  */
-                 pt->nonlocal = uses_global_memory;
-                 pt->escaped = uses_global_memory;
+                 if (uses_global_memory)
+                   {
+                     pt->nonlocal = uses_global_memory;
+                     pt->escaped = uses_global_memory;
+                   }
                }
              else if (uses_global_memory)
                {
@@ -7572,17 +7573,18 @@ compute_points_to_sets (void)
              determine_global_memory_access (stmt, &writes_global_memory,
                                              NULL, NULL);
 
-             if (!writes_global_memory)
-               ;
-             else if ((vi = lookup_call_clobber_vi (stmt)) != NULL)
+             if ((vi = lookup_call_clobber_vi (stmt)) != NULL)
                {
                  *pt = find_what_var_points_to (cfun->decl, vi);
                  /* Escaped (and thus nonlocal) variables are always
                     implicitly clobbered by calls.  */
                  /* ???  ESCAPED can be empty even though NONLOCAL
                     always escaped.  */
-                 pt->nonlocal = writes_global_memory;
-                 pt->escaped = writes_global_memory;
+                 if (writes_global_memory)
+                   {
+                     pt->nonlocal = writes_global_memory;
+                     pt->escaped = writes_global_memory;
+                   }
                }
              else if (writes_global_memory)
                {

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