From: Martin Jambor <mjambor@suse.cz>
Date: Tue, 9 Aug 2016 16:05:30 +0000 (+0200)
Subject: [PR ipa/71981] Make get_dynamic_type grok MEM_REF
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=04d6d3b6d77d247616543dedad7ee239368591a5;p=gcc.git

[PR ipa/71981] Make get_dynamic_type grok MEM_REF

2016-08-09  Martin Jambor  <mjambor@suse.cz>

        PR ipa/71981
        * ipa-polymorphic-call.c (get_dynamic_type): Bail out gracefully
        if instance is a MEM_REF.

testsuite/
        PR ipa/71981
        * gcc.dg/ipa/pr71981.c: New test.

From-SVN: r239294
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 7ae805542e6..854dea5249a 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2016-08-09  Martin Jambor  <mjambor@suse.cz>
+
+        PR ipa/71981
+        * ipa-polymorphic-call.c (get_dynamic_type): Bail out gracefully
+        if instance is a MEM_REF.
+
 2016-08-09  Uros Bizjak  <ubizjak@gmail.com>
 
 	PR target/72843
diff --git a/gcc/ipa-polymorphic-call.c b/gcc/ipa-polymorphic-call.c
index 56f334471de..f7ef6aa94fd 100644
--- a/gcc/ipa-polymorphic-call.c
+++ b/gcc/ipa-polymorphic-call.c
@@ -1544,6 +1544,11 @@ ipa_polymorphic_call_context::get_dynamic_type (tree instance,
   if (!maybe_in_construction && !maybe_derived_type)
     return false;
 
+  /* If we are in fact not looking at any object object or the instance is
+     some placement new into a random load, give up straight away.  */
+  if (TREE_CODE (instance) == MEM_REF)
+    return false;
+
   /* We need to obtain refernce to virtual table pointer.  It is better
      to look it up in the code rather than build our own.  This require bit
      of pattern matching, but we end up verifying that what we found is
@@ -1664,7 +1669,6 @@ ipa_polymorphic_call_context::get_dynamic_type (tree instance,
   tci.offset = instance_offset;
   tci.instance = instance;
   tci.vtbl_ptr_ref = instance_ref;
-  gcc_assert (TREE_CODE (instance) != MEM_REF);
   tci.known_current_type = NULL_TREE;
   tci.known_current_offset = 0;
   tci.otr_type = otr_type;
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 5674f97b67e..34834693309 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2016-08-09  Martin Jambor  <mjambor@suse.cz>
+
+        PR ipa/71981
+        * gcc.dg/ipa/pr71981.c: New test.
+
 2016-08-09  Bin Cheng  <bin.cheng@arm.com>
 
 	PR tree-optimization/33707
diff --git a/gcc/testsuite/gcc.dg/ipa/pr71981.c b/gcc/testsuite/gcc.dg/ipa/pr71981.c
new file mode 100644
index 00000000000..1b2160246e8
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/ipa/pr71981.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -w" } */
+
+int **a;
+static void fn1(char **p1) {
+  char s = *p1, b = &s;
+  while (*fn2()[a])
+    ;
+}
+int main() { fn1(""); return 0; }