--- a/src/cpu/x86/vm/stubGenerator_x86_64.cpp	Tue Feb 07 12:34:31 2012 -0800
+++ b/src/cpu/x86/vm/stubGenerator_x86_64.cpp	Thu Feb 09 18:01:20 2012 -0800
@@ -2978,7 +2978,9 @@
     int frame_complete = __ pc() - start;
 
     // Set up last_Java_sp and last_Java_fp
-    __ set_last_Java_frame(rsp, rbp, NULL);
+    address the_pc = __ pc();
+    __ set_last_Java_frame(rsp, rbp, the_pc);
+    __ andptr(rsp, -(StackAlignmentInBytes));    // Align stack
 
     // Call runtime
     if (arg1 != noreg) {
@@ -2997,7 +2999,7 @@
 
     oop_maps->add_gc_map(__ pc() - start, map);
 
-    __ reset_last_Java_frame(true, false);
+    __ reset_last_Java_frame(true, true);
 
     __ leave(); // required for proper stackwalking of RuntimeStub frame
 

--- a/src/os_cpu/bsd_x86/vm/os_bsd_x86.cpp	Tue Feb 07 12:34:31 2012 -0800
+++ b/src/os_cpu/bsd_x86/vm/os_bsd_x86.cpp	Thu Feb 09 18:01:20 2012 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2011, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2012, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -362,7 +362,7 @@
 }
 
 intptr_t* _get_previous_fp() {
-#if defined(SPARC_WORKS) || defined(__clang__)
+#if defined(SPARC_WORKS) || defined(__clang__) || defined(__llvm__)
   register intptr_t **ebp;
   __asm__("mov %%"SPELL_REG_FP", %0":"=r"(ebp));
 #else

--- a/src/share/vm/opto/graphKit.cpp	Tue Feb 07 12:34:31 2012 -0800
+++ b/src/share/vm/opto/graphKit.cpp	Thu Feb 09 18:01:20 2012 -0800
@@ -1522,6 +1522,11 @@
                           const TypeOopPtr* val_type,
                           BasicType bt,
                           bool use_precise) {
+  // Transformation of a value which could be NULL pointer (CastPP #NULL)
+  // could be delayed during Parse (for example, in adjust_map_after_if()).
+  // Execute transformation here to avoid barrier generation in such case.
+  if (_gvn.type(val) == TypePtr::NULL_PTR)
+    val = _gvn.makecon(TypePtr::NULL_PTR);
 
   set_control(ctl);
   if (stopped()) return top(); // Dead path ?

--- a/src/share/vm/opto/library_call.cpp	Tue Feb 07 12:34:31 2012 -0800
+++ b/src/share/vm/opto/library_call.cpp	Thu Feb 09 18:01:20 2012 -0800
@@ -2678,7 +2678,13 @@
     cas = _gvn.transform(new (C, 5) CompareAndSwapLNode(control(), mem, adr, newval, oldval));
     break;
   case T_OBJECT:
-     // reference stores need a store barrier.
+    // Transformation of a value which could be NULL pointer (CastPP #NULL)
+    // could be delayed during Parse (for example, in adjust_map_after_if()).
+    // Execute transformation here to avoid barrier generation in such case.
+    if (_gvn.type(newval) == TypePtr::NULL_PTR)
+      newval = _gvn.makecon(TypePtr::NULL_PTR);
+
+    // Reference stores need a store barrier.
     // (They don't if CAS fails, but it isn't worth checking.)
     pre_barrier(true /* do_load*/,
                 control(), base, adr, alias_idx, newval, value_type->make_oopptr(),

--- a/src/share/vm/opto/macro.cpp	Tue Feb 07 12:34:31 2012 -0800
+++ b/src/share/vm/opto/macro.cpp	Thu Feb 09 18:01:20 2012 -0800
@@ -234,11 +234,20 @@
     }
   } else {
     // G1 pre/post barriers
-    assert(p2x->outcnt() == 2, "expects 2 users: Xor and URShift nodes");
+    assert(p2x->outcnt() <= 2, "expects 1 or 2 users: Xor and URShift nodes");
     // It could be only one user, URShift node, in Object.clone() instrinsic
     // but the new allocation is passed to arraycopy stub and it could not
     // be scalar replaced. So we don't check the case.
 
+    // An other case of only one user (Xor) is when the value check for NULL
+    // in G1 post barrier is folded after CCP so the code which used URShift
+    // is removed.
+
+    // Take Region node before eliminating post barrier since it also
+    // eliminates CastP2X node when it has only one user.
+    Node* this_region = p2x->in(0);
+    assert(this_region != NULL, "");
+
     // Remove G1 post barrier.
 
     // Search for CastP2X->Xor->URShift->Cmp path which
@@ -263,8 +272,6 @@
     // Remove G1 pre barrier.
 
     // Search "if (marking != 0)" check and set it to "false".
-    Node* this_region = p2x->in(0);
-    assert(this_region != NULL, "");
     // There is no G1 pre barrier if previous stored value is NULL
     // (for example, after initialization).
     if (this_region->is_Region() && this_region->req() == 3) {
@@ -292,7 +299,7 @@
     }
     // Now CastP2X can be removed since it is used only on dead path
     // which currently still alive until igvn optimize it.
-    assert(p2x->unique_out()->Opcode() == Op_URShiftX, "");
+    assert(p2x->outcnt() == 0 || p2x->unique_out()->Opcode() == Op_URShiftX, "");
     _igvn.replace_node(p2x, top());
   }
 }