--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/shared/c2/barrierSetC2.hpp Fri May 18 14:51:06 2018 +0200
@@ -0,0 +1,217 @@
+/*
+ * Copyright (c) 2018, 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
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_GC_SHARED_C2_BARRIERSETC2_HPP
+#define SHARE_GC_SHARED_C2_BARRIERSETC2_HPP
+
+#include "memory/allocation.hpp"
+#include "oops/accessDecorators.hpp"
+#include "opto/loopnode.hpp"
+#include "opto/memnode.hpp"
+#include "utilities/globalDefinitions.hpp"
+
+// This means the access is mismatched. This means the value of an access
+// is not equivalent to the value pointed to by the address.
+const DecoratorSet C2_MISMATCHED = DECORATOR_LAST << 1;
+// The access may not be aligned to its natural size.
+const DecoratorSet C2_UNALIGNED = DECORATOR_LAST << 2;
+// The atomic cmpxchg is weak, meaning that spurious false negatives are allowed,
+// but never false positives.
+const DecoratorSet C2_WEAK_CMPXCHG = DECORATOR_LAST << 3;
+// This denotes that a load has control dependency.
+const DecoratorSet C2_CONTROL_DEPENDENT_LOAD = DECORATOR_LAST << 4;
+// This denotes that a load that must be pinned.
+const DecoratorSet C2_PINNED_LOAD = DECORATOR_LAST << 5;
+// This denotes that the access is produced from the sun.misc.Unsafe intrinsics.
+const DecoratorSet C2_UNSAFE_ACCESS = DECORATOR_LAST << 6;
+// This denotes that the access mutates state.
+const DecoratorSet C2_WRITE_ACCESS = DECORATOR_LAST << 7;
+// This denotes that the access reads state.
+const DecoratorSet C2_READ_ACCESS = DECORATOR_LAST << 8;
+
+class GraphKit;
+class IdealKit;
+class Node;
+class Type;
+class TypePtr;
+class PhaseMacroExpand;
+
+// This class wraps a node and a type.
+class C2AccessValue: public StackObj {
+protected:
+ Node* _node;
+ const Type* _type;
+
+public:
+ C2AccessValue(Node* node, const Type* type) :
+ _node(node),
+ _type(type) {}
+
+ Node* node() const { return _node; }
+ const Type* type() const { return _type; }
+
+ void set_node(Node* node) { _node = node; }
+};
+
+// This class wraps a node and a pointer type.
+class C2AccessValuePtr: public C2AccessValue {
+ int _alias_idx;
+
+public:
+ C2AccessValuePtr(Node* node, const TypePtr* type) :
+ C2AccessValue(node, reinterpret_cast<const Type*>(type)) {}
+
+ const TypePtr* type() const { return reinterpret_cast<const TypePtr*>(_type); }
+ int alias_idx() const { return _alias_idx; }
+};
+
+// This class wraps a bunch of context parameters thare are passed around in the
+// BarrierSetC2 backend hierarchy, for loads and stores, to reduce boiler plate.
+class C2Access: public StackObj {
+protected:
+ GraphKit* _kit;
+ DecoratorSet _decorators;
+ BasicType _type;
+ Node* _base;
+ C2AccessValuePtr& _addr;
+ Node* _raw_access;
+
+ void fixup_decorators();
+ void* barrier_set_state() const;
+
+public:
+ C2Access(GraphKit* kit, DecoratorSet decorators,
+ BasicType type, Node* base, C2AccessValuePtr& addr) :
+ _kit(kit),
+ _decorators(decorators),
+ _type(type),
+ _base(base),
+ _addr(addr),
+ _raw_access(NULL)
+ {
+ fixup_decorators();
+ }
+
+ GraphKit* kit() const { return _kit; }
+ DecoratorSet decorators() const { return _decorators; }
+ Node* base() const { return _base; }
+ C2AccessValuePtr& addr() const { return _addr; }
+ BasicType type() const { return _type; }
+ bool is_oop() const { return _type == T_OBJECT || _type == T_ARRAY; }
+ bool is_raw() const { return (_decorators & AS_RAW) != 0; }
+ Node* raw_access() const { return _raw_access; }
+
+ void set_raw_access(Node* raw_access) { _raw_access = raw_access; }
+ virtual void set_memory() {} // no-op for normal accesses, but not for atomic accesses.
+
+ MemNode::MemOrd mem_node_mo() const;
+ bool needs_cpu_membar() const;
+
+ template <typename T>
+ T barrier_set_state_as() const {
+ return reinterpret_cast<T>(barrier_set_state());
+ }
+};
+
+// This class wraps a bunch of context parameters thare are passed around in the
+// BarrierSetC2 backend hierarchy, for atomic accesses, to reduce boiler plate.
+class C2AtomicAccess: public C2Access {
+ Node* _memory;
+ uint _alias_idx;
+ bool _needs_pinning;
+
+public:
+ C2AtomicAccess(GraphKit* kit, DecoratorSet decorators, BasicType type,
+ Node* base, C2AccessValuePtr& addr, uint alias_idx) :
+ C2Access(kit, decorators, type, base, addr),
+ _memory(NULL),
+ _alias_idx(alias_idx),
+ _needs_pinning(true) {}
+
+ // Set the memory node based on the current memory slice.
+ virtual void set_memory();
+
+ Node* memory() const { return _memory; }
+ uint alias_idx() const { return _alias_idx; }
+ bool needs_pinning() const { return _needs_pinning; }
+
+ void set_needs_pinning(bool value) { _needs_pinning = value; }
+};
+
+// This is the top-level class for the backend of the Access API in C2.
+// The top-level class is responsible for performing raw accesses. The
+// various GC barrier sets inherit from the BarrierSetC2 class to sprinkle
+// barriers into the accesses.
+class BarrierSetC2: public CHeapObj<mtGC> {
+protected:
+ virtual void resolve_address(C2Access& access) const;
+ virtual Node* store_at_resolved(C2Access& access, C2AccessValue& val) const;
+ virtual Node* load_at_resolved(C2Access& access, const Type* val_type) const;
+
+ virtual Node* atomic_cmpxchg_val_at_resolved(C2AtomicAccess& access, Node* expected_val,
+ Node* new_val, const Type* val_type) const;
+ virtual Node* atomic_cmpxchg_bool_at_resolved(C2AtomicAccess& access, Node* expected_val,
+ Node* new_val, const Type* value_type) const;
+ virtual Node* atomic_xchg_at_resolved(C2AtomicAccess& access, Node* new_val, const Type* val_type) const;
+ virtual Node* atomic_add_at_resolved(C2AtomicAccess& access, Node* new_val, const Type* val_type) const;
+
+public:
+ // This is the entry-point for the backend to perform accesses through the Access API.
+ virtual Node* store_at(C2Access& access, C2AccessValue& val) const;
+ virtual Node* load_at(C2Access& access, const Type* val_type) const;
+
+ virtual Node* atomic_cmpxchg_val_at(C2AtomicAccess& access, Node* expected_val,
+ Node* new_val, const Type* val_type) const;
+ virtual Node* atomic_cmpxchg_bool_at(C2AtomicAccess& access, Node* expected_val,
+ Node* new_val, const Type* val_type) const;
+ virtual Node* atomic_xchg_at(C2AtomicAccess& access, Node* new_val, const Type* value_type) const;
+ virtual Node* atomic_add_at(C2AtomicAccess& access, Node* new_val, const Type* value_type) const;
+
+ virtual void clone(GraphKit* kit, Node* src, Node* dst, Node* size, bool is_array) const;
+
+ // These are general helper methods used by C2
+ virtual bool array_copy_requires_gc_barriers(BasicType type) const { return false; }
+
+ // Support for GC barriers emitted during parsing
+ virtual bool is_gc_barrier_node(Node* node) const { return false; }
+ virtual Node* step_over_gc_barrier(Node* c) const { return c; }
+
+ // Support for macro expanded GC barriers
+ virtual void register_potential_barrier_node(Node* node) const { }
+ virtual void unregister_potential_barrier_node(Node* node) const { }
+ virtual void eliminate_gc_barrier(PhaseMacroExpand* macro, Node* node) const { }
+ virtual void enqueue_useful_gc_barrier(Unique_Node_List &worklist, Node* node) const {}
+ virtual void eliminate_useless_gc_barriers(Unique_Node_List &useful) const {}
+ virtual void add_users_to_worklist(Unique_Node_List* worklist) const {}
+
+ // Allow barrier sets to have shared state that is preserved across a compilation unit.
+ // This could for example comprise macro nodes to be expanded during macro expansion.
+ virtual void* create_barrier_state(Arena* comp_arena) const { return NULL; }
+ // If the BarrierSetC2 state has kept macro nodes in its compilation unit state to be
+ // expanded later, then now is the time to do so.
+ virtual bool expand_macro_nodes(PhaseMacroExpand* macro) const { return false; }
+ virtual void verify_gc_barriers(bool post_parse) const {}
+};
+
+#endif // SHARE_GC_SHARED_C2_BARRIERSETC2_HPP