[gcc r12-784] PR middle-end/100574 - ICE in size_remaining, at builtins.c

[gcc r12-784] PR middle-end/100574 - ICE in size_remaining, at builtins.c

[Martin Sebor]

https://gcc.gnu.org/g:5380e3c137b2bb63acd789cd09d01a4edc0a01c3

commit r12-784-g5380e3c137b2bb63acd789cd09d01a4edc0a01c3
Author: Martin Sebor <msebor@redhat.com>
Date:   Thu May 13 16:20:45 2021 -0600

    PR middle-end/100574 - ICE in size_remaining, at builtins.c
    
    gcc/ChangeLog:
    
            PR middle-end/100574
            * builtins.c (access_ref::get_ref): Improve detection of PHIs with
            all null arguments.

Diff:
---
 gcc/builtins.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/gcc/builtins.c b/gcc/builtins.c
index 2f0efae11e8..e1b284846b1 100644
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -362,15 +362,6 @@ access_ref::get_ref (vec<access_ref> *all_refs,
 	same_ref.offrng[1] = phi_arg_ref.offrng[1];
     }
 
-  if (phi_ref.sizrng[0] < 0)
-    {
-      /* Fail if none of the PHI's arguments resulted in updating PHI_REF
-	 (perhaps because they have all been already visited by prior
-	 recursive calls).  */
-      psnlim->leave_phi (ref);
-      return NULL_TREE;
-    }
-
   if (!same_ref.ref && same_ref.offrng[0] != 0)
     /* Clear BASE0 if not all the arguments refer to the same object and
        if not all their offsets are zero-based.  This allows the final
@@ -390,6 +381,15 @@ access_ref::get_ref (vec<access_ref> *all_refs,
       phi_ref.parmarray = parmarray;
     }
 
+  if (phi_ref.sizrng[0] < 0)
+    {
+      /* Fail if none of the PHI's arguments resulted in updating PHI_REF
+	 (perhaps because they have all been already visited by prior
+	 recursive calls).  */
+      psnlim->leave_phi (ref);
+      return NULL_TREE;
+    }
+
   /* Avoid changing *THIS.  */
   if (pref && pref != this)
     *pref = phi_ref;