8278790: Inner loop of long loop nest runs for too few iterations

Reviewed-by: chagedorn, neliasso

Author: rwestrel

src/hotspot/share/opto/loopnode.cpp

@@ -830,10 +830,6 @@ bool PhaseIdealLoop::create_loop_nest(IdealLoopTree* loop, Node_List &old_new) {
     return false;
   }
 
-  // May not have gone thru igvn yet so don't use _igvn.type(phi) (PhaseIdealLoop::is_counted_loop() sets the iv phi's type)
-  const TypeInteger* phi_t = phi->bottom_type()->is_integer(bt);
-  assert(phi_t->hi_as_long() >= phi_t->lo_as_long(), "dead phi?");
-  iters_limit = checked_cast<int>(MIN2((julong)iters_limit, (julong)(phi_t->hi_as_long() - phi_t->lo_as_long())));
 
   IfNode* exit_test = head->loopexit();
   BoolTest::mask mask = exit_test->as_BaseCountedLoopEnd()->test_trip();
@@ -851,6 +847,11 @@ bool PhaseIdealLoop::create_loop_nest(IdealLoopTree* loop, Node_List &old_new) {
     }
   }
 
+  // May not have gone thru igvn yet so don't use _igvn.type(phi) (PhaseIdealLoop::is_counted_loop() sets the iv phi's type)
+  const TypeInteger* phi_t = phi->bottom_type()->is_integer(bt);
+  assert(phi_t->hi_as_long() >= phi_t->lo_as_long(), "dead phi?");
+  iters_limit = checked_cast<int>(MIN2((julong)iters_limit, (julong)(phi_t->hi_as_long() - phi_t->lo_as_long())));
+
   // We need a safepoint to insert empty predicates for the inner loop.
   SafePointNode* safepoint;
   if (bt == T_INT && head->as_CountedLoop()->is_strip_mined()) {