ifcvt: Call fixup_partitions (PR83361)

After converting a conditional branch to an unconditional trap to a
conditional trap, if the original trap is still reachable from another
path, it may be that it is in a hot basic block  and only reachable from
cold blocks.  Fix that up.


	PR rtl-optimization/83361
	* ifcvt.c (if_convert): Call fixup_partitions.

gcc/testsuite/
	PR rtl-optimization/83361
	* gcc.dg/pr83361.c: New testcase.

From-SVN: r255550

gcc/ChangeLog

+2017-12-11  Segher Boessenkool  <segher@kernel.crashing.org>
+
+	PR rtl-optimization/83361
+	* ifcvt.c (if_convert): Call fixup_partitions.
+
 2017-12-11  Will Schmidt  <will_schmidt@vnet.ibm.com>
 
 	* config/rs6000/rs6000.c (rs6000_gimple_fold_builtin): Add support for

gcc/ifcvt.c

@@ -5446,6 +5446,10 @@ if_convert (bool after_combine)
   if (optimize == 1)
     df_remove_problem (df_live);
 
+  /* Some non-cold blocks may now be only reachable from cold blocks.
+     Fix that up.  */
+  fixup_partitions ();
+
   checking_verify_flow_info ();
 }
 

gcc/testsuite/ChangeLog

+2017-12-11  Segher Boessenkool  <segher@kernel.crashing.org>
+
+	PR rtl-optimization/83361
+	* gcc.dg/pr83361.c: New testcase.
+
 2017-12-11  Will Schmidt  <will_schmidt@vnet.ibm.com>
 
 	* gcc.target/powerpc/fold-vec-splat-misc-invalid.c: New.

gcc/testsuite/gcc.dg/pr83361.c

+/* PR rtl-optimization/83361 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -freorder-blocks-and-partition" } */
+
+#include <limits.h>
+
+int yz;
+
+void
+tq (int z3)
+{
+  unsigned long long int n8 = (unsigned long long int)INT_MAX + 1;
+  int *ey = &yz;
+
+  if (yz == 0)
+    {
+      int bc;
+
+      yz = 1;
+      while (yz != 0)
+        {
+          *ey *= bc;
+          n8 = !!(1 / ((unsigned long long int)yz == n8));
+          ey = &z3;
+        }
+
+      while (z3 != 0)
+        {
+        }
+    }
+
+  z3 = (n8 != 0) && (*ey != 0);
+  z3 = yz / z3;
+  if (z3 < 0)
+    {
+      if (yz != 0)
+        yz = 0;
+      yz /= 0;
+    }
+}