[PATCH] ipa: Check cst type when propagating controled uses info (PR 105639)

[Martin Jambor]

Hi,

PR 105639 shows that code with type-mismatches can trigger an assert
after runnning into a branch that was inteded only for references to
variables - as opposed to references to functions.  Fixed by moving
the condition from the assert to the guarding if statement.

Bootstrapped and tested on x86_64.  OK for trunk and then gcc 12?

Thanks,

Martin



gcc/ChangeLog:

2022-05-25  Martin Jambor  <mjam...@suse.cz>

        PR ipa/105639
        * ipa-prop.cc (propagate_controlled_uses): Check type of the
        constant before adding a LOAD reference.

gcc/testsuite/ChangeLog:

2022-05-25  Martin Jambor  <mjam...@suse.cz>

        PR ipa/105639
        * gcc.dg/ipa/pr105639.c: New test.
---
 gcc/ipa-prop.cc                     | 10 ++++------
 gcc/testsuite/gcc.dg/ipa/pr105639.c | 16 ++++++++++++++++
 2 files changed, 20 insertions(+), 6 deletions(-)
 create mode 100644 gcc/testsuite/gcc.dg/ipa/pr105639.c

diff --git a/gcc/ipa-prop.cc b/gcc/ipa-prop.cc
index c6c745f84a0..afd9222b5a2 100644
--- a/gcc/ipa-prop.cc
+++ b/gcc/ipa-prop.cc
@@ -4187,14 +4187,13 @@ propagate_controlled_uses (struct cgraph_edge *cs)
        {
          int d = ipa_get_controlled_uses (old_root_info, i);
          int c = rdesc->refcount;
+         tree cst = ipa_get_jf_constant (jf);
          rdesc->refcount = combine_controlled_uses_counters (c, d);
          if (rdesc->refcount != IPA_UNDESCRIBED_USE
-             && ipa_get_param_load_dereferenced (old_root_info, i))
+             && ipa_get_param_load_dereferenced (old_root_info, i)
+             && TREE_CODE (cst) == ADDR_EXPR
+             && TREE_CODE (TREE_OPERAND (cst, 0)) == VAR_DECL)
            {
-             tree cst = ipa_get_jf_constant (jf);
-             gcc_checking_assert (TREE_CODE (cst) == ADDR_EXPR
-                                  && (TREE_CODE (TREE_OPERAND (cst, 0))
-                                      == VAR_DECL));
              symtab_node *n = symtab_node::get (TREE_OPERAND (cst, 0));
              new_root->create_reference (n, IPA_REF_LOAD, NULL);
              if (dump_file)
@@ -4204,7 +4203,6 @@ propagate_controlled_uses (struct cgraph_edge *cs)
            }
          if (rdesc->refcount == 0)
            {
-             tree cst = ipa_get_jf_constant (jf);
              gcc_checking_assert (TREE_CODE (cst) == ADDR_EXPR
                                   && ((TREE_CODE (TREE_OPERAND (cst, 0))
                                        == FUNCTION_DECL)
diff --git a/gcc/testsuite/gcc.dg/ipa/pr105639.c 
b/gcc/testsuite/gcc.dg/ipa/pr105639.c
new file mode 100644
index 00000000000..5534fe93fbf
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ipa/pr105639.c
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+/* { dg-options "-O -w" } */
+
+void typedef (*cb) (void);
+
+static void
+bar (cb *fp)
+{
+  (*fp) ();
+}
+
+void
+foo (void)
+{
+  bar (foo);
+}
-- 
2.36.0