# HG changeset patch
# Parent 6075f6799044c92941569c188efb3a3208b34236
diff -r 6075f6799044 -r 1f3e014a6d3d src/hotspot/share/gc/shenandoah/c2/shenandoahSupport.cpp
--- a/src/hotspot/share/gc/shenandoah/c2/shenandoahSupport.cpp	Fri Feb 22 12:21:36 2019 +0100
+++ b/src/hotspot/share/gc/shenandoah/c2/shenandoahSupport.cpp	Wed Mar 06 10:42:31 2019 +0100
@@ -1458,16 +1458,11 @@
     assert(val->bottom_type()->make_oopptr(), "need oop");
     assert(val->bottom_type()->make_oopptr()->const_oop() == NULL, "expect non-constant");
 
-    enum { _heap_stable = 1, _heap_unstable, PATH_LIMIT };
+    enum { _heap_stable = 1, _not_cset, _not_equal, _evac_path, _null_path, PATH_LIMIT };
     Node* region = new RegionNode(PATH_LIMIT);
     Node* val_phi = new PhiNode(region, uncasted_val->bottom_type()->is_oopptr());
     Node* raw_mem_phi = PhiNode::make(region, raw_mem, Type::MEMORY, TypeRawPtr::BOTTOM);
 
-    enum { _not_cset = 1, _not_equal, _evac_path, _null_path, PATH_LIMIT2 };
-    Node* region2 = new RegionNode(PATH_LIMIT2);
-    Node* val_phi2 = new PhiNode(region2, uncasted_val->bottom_type()->is_oopptr());
-    Node* raw_mem_phi2 = PhiNode::make(region2, raw_mem, Type::MEMORY, TypeRawPtr::BOTTOM);
-
     // Stable path.
     test_heap_stable(ctrl, raw_mem, heap_stable_ctrl, phase);
     IfNode* heap_stable_iff = heap_stable_ctrl->in(0)->as_If();
@@ -1482,13 +1477,13 @@
     test_null(ctrl, val, null_ctrl, phase);
     if (null_ctrl != NULL) {
       reg2_ctrl = null_ctrl->in(0);
-      region2->init_req(_null_path, null_ctrl);
-      val_phi2->init_req(_null_path, uncasted_val);
-      raw_mem_phi2->init_req(_null_path, raw_mem);
+      region->init_req(_null_path, null_ctrl);
+      val_phi->init_req(_null_path, uncasted_val);
+      raw_mem_phi->init_req(_null_path, raw_mem);
     } else {
-      region2->del_req(_null_path);
-      val_phi2->del_req(_null_path);
-      raw_mem_phi2->del_req(_null_path);
+      region->del_req(_null_path);
+      val_phi->del_req(_null_path);
+      raw_mem_phi->del_req(_null_path);
     }
 
     // Test for in-cset.
@@ -1497,22 +1492,14 @@
     in_cset_fast_test(ctrl, not_cset_ctrl, uncasted_val, raw_mem, phase);
     if (not_cset_ctrl != NULL) {
       if (reg2_ctrl == NULL) reg2_ctrl = not_cset_ctrl->in(0);
-      region2->init_req(_not_cset, not_cset_ctrl);
-      val_phi2->init_req(_not_cset, uncasted_val);
-      raw_mem_phi2->init_req(_not_cset, raw_mem);
+      region->init_req(_not_cset, not_cset_ctrl);
+      val_phi->init_req(_not_cset, uncasted_val);
+      raw_mem_phi->init_req(_not_cset, raw_mem);
     }
 
     // Resolve object when orig-value is in cset.
     // Make the unconditional resolve for fwdptr, not the read barrier.
     Node* new_val = uncasted_val;
-    if (unc_ctrl != NULL) {
-      // Clone the null check in this branch to allow implicit null check
-      new_val = clone_null_check(ctrl, val, unc_ctrl, phase);
-      fix_null_check(unc, unc_ctrl, ctrl->in(0)->as_If()->proj_out(0), uses, phase);
-
-      IfNode* iff = unc_ctrl->in(0)->as_If();
-      phase->igvn().replace_input_of(iff, 1, phase->igvn().intcon(1));
-    }
     Node* addr = new AddPNode(new_val, uncasted_val, phase->igvn().MakeConX(ShenandoahBrooksPointer::byte_offset()));
     phase->register_new_node(addr, ctrl);
     assert(val->bottom_type()->isa_oopptr(), "what else?");
@@ -1536,25 +1523,17 @@
     phase->register_control(if_eq, loop, iff);
 
     // Wire up not-equal-path in slots 3.
-    region2->init_req(_not_equal, if_not_eq);
-    val_phi2->init_req(_not_equal, fwd);
-    raw_mem_phi2->init_req(_not_equal, raw_mem);
+    region->init_req(_not_equal, if_not_eq);
+    val_phi->init_req(_not_equal, fwd);
+    raw_mem_phi->init_req(_not_equal, raw_mem);
 
     // Call wb-stub and wire up that path in slots 4
     Node* result_mem = NULL;
     ctrl = if_eq;
     call_lrb_stub(ctrl, fwd, result_mem, raw_mem, phase);
-    region2->init_req(_evac_path, ctrl);
-    val_phi2->init_req(_evac_path, fwd);
-    raw_mem_phi2->init_req(_evac_path, result_mem);
-
-    phase->register_control(region2, loop, reg2_ctrl);
-    phase->register_new_node(val_phi2, region2);
-    phase->register_new_node(raw_mem_phi2, region2);
-
-    region->init_req(_heap_unstable, region2);
-    val_phi->init_req(_heap_unstable, val_phi2);
-    raw_mem_phi->init_req(_heap_unstable, raw_mem_phi2);
+    region->init_req(_evac_path, ctrl);
+    val_phi->init_req(_evac_path, fwd);
+    raw_mem_phi->init_req(_evac_path, result_mem);
 
     phase->register_control(region, loop, heap_stable_iff);
     Node* out_val = val_phi;