[PATCH] objsz: Don't call replace_uses_by on SSA_NAME_OCCURS_IN_ABNORMAL_PHI [PR94423]

[Jakub Jelinek via Gcc-patches]

Hi!

The following testcase ICEs because the objsz pass calls replace_uses_by
on SSA_NAME_OCCURS_IN_ABNORMAL_PHI SSA_NAME.  The following patch instead
of that calls replace_call_with_value, which will turn it into
  xyz_123(ab) = 234;

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

2020-04-01  Jakub Jelinek  <ja...@redhat.com>

        PR middle-end/94423
        * tree-object-size.c (pass_object_sizes::execute): Don't call
        replace_uses_by for SSA_NAME_OCCURS_IN_ABNORMAL_PHI lhs, instead
        call replace_call_with_value.

        * gcc.dg/ubsan/pr94423.c: New test.

--- gcc/tree-object-size.c.jj   2020-01-12 11:54:38.498381952 +0100
+++ gcc/tree-object-size.c      2020-03-31 14:35:34.956831791 +0200
@@ -1393,7 +1393,10 @@ pass_object_sizes::execute (function *fu
            }
 
          /* Propagate into all uses and fold those stmts.  */
-         replace_uses_by (lhs, result);
+         if (!SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs))
+           replace_uses_by (lhs, result);
+         else
+           replace_call_with_value (&i, result);
        }
     }
 
--- gcc/testsuite/gcc.dg/ubsan/pr94423.c.jj     2020-03-31 14:38:15.101423280 
+0200
+++ gcc/testsuite/gcc.dg/ubsan/pr94423.c        2020-03-31 14:32:31.562589949 
+0200
@@ -0,0 +1,17 @@
+/* PR middle-end/94423 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fsanitize=object-size" } */
+
+void foo (void);
+typedef struct { long buf[22]; } jmp_buf[1];
+extern int sigsetjmp (jmp_buf, int) __attribute__ ((__nothrow__));
+jmp_buf buf;
+
+void
+bar (int *c)
+{
+  while (*c)
+    foo ();
+  while (*c)
+    sigsetjmp (buf, 0);
+}

        Jakub