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src/share/vm/gc/shared/barrierSet.hpp
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rev 12906 : [mq]: gc_interface
@@ -23,50 +23,48 @@
*/
#ifndef SHARE_VM_GC_SHARED_BARRIERSET_HPP
#define SHARE_VM_GC_SHARED_BARRIERSET_HPP
-#include "memory/memRegion.hpp"
-#include "oops/oopsHierarchy.hpp"
+#include "gc/shared/barrierSetConfig.hpp"
+#include "runtime/access.hpp"
+#include "runtime/accessBackend.hpp"
#include "utilities/fakeRttiSupport.hpp"
+class JavaThread;
+class BarrierSetCodeGen;
+class C1BarrierSetCodeGen;
+class C2BarrierSetCodeGen;
+
// This class provides the interface between a barrier implementation and
// the rest of the system.
class BarrierSet: public CHeapObj<mtGC> {
friend class VMStructs;
public:
+ enum Name {
+#define BARRIER_SET_DECLARE_BS_ENUM(bs_name) bs_name ,
+ FOR_EACH_BARRIER_SET_DO(BARRIER_SET_DECLARE_BS_ENUM)
+#undef BARRIER_SET_DECLARE_BS_ENUM
+ UnknownBS
+ };
+protected:
// Fake RTTI support. For a derived class T to participate
// - T must have a corresponding Name entry.
// - GetName<T> must be specialized to return the corresponding Name
// entry.
// - If T is a base class, the constructor must have a FakeRtti
// parameter and pass it up to its base class, with the tag set
// augmented with the corresponding Name entry.
// - If T is a concrete class, the constructor must create a
// FakeRtti object whose tag set includes the corresponding Name
// entry, and pass it up to its base class.
-
- enum Name { // associated class
- ModRef, // ModRefBarrierSet
- CardTableModRef, // CardTableModRefBS
- CardTableForRS, // CardTableModRefBSForCTRS
- CardTableExtension, // CardTableExtension
- G1SATBCT, // G1SATBCardTableModRefBS
- G1SATBCTLogging // G1SATBCardTableLoggingModRefBS
- };
-
-protected:
typedef FakeRttiSupport<BarrierSet, Name> FakeRtti;
private:
FakeRtti _fake_rtti;
- // Metafunction mapping a class derived from BarrierSet to the
- // corresponding Name enum tag.
- template<typename T> struct GetName;
-
// Downcast argument to a derived barrier set type.
// The cast is checked in a debug build.
// T must have a specialization for BarrierSet::GetName<T>.
template<typename T> friend T* barrier_set_cast(BarrierSet* bs);
@@ -78,150 +76,91 @@
// Test whether this object is of the type corresponding to bsn.
bool is_a(BarrierSet::Name bsn) const { return _fake_rtti.has_tag(bsn); }
// End of fake RTTI support.
-public:
- enum Flags {
- None = 0,
- TargetUninitialized = 1
- };
-
protected:
- // Some barrier sets create tables whose elements correspond to parts of
- // the heap; the CardTableModRefBS is an example. Such barrier sets will
- // normally reserve space for such tables, and commit parts of the table
- // "covering" parts of the heap that are committed. At most one covered
- // region per generation is needed.
- static const int _max_covered_regions = 2;
-
- BarrierSet(const FakeRtti& fake_rtti) : _fake_rtti(fake_rtti) { }
+ BarrierSet(const FakeRtti& fake_rtti) : _fake_rtti(fake_rtti), _code_gen(NULL), _c1_code_gen(NULL), _c2_code_gen(NULL) { }
~BarrierSet() { }
-public:
+ static BarrierSet* _bs;
- // These operations indicate what kind of barriers the BarrierSet has.
- virtual bool has_read_ref_barrier() = 0;
- virtual bool has_read_prim_barrier() = 0;
- virtual bool has_write_ref_barrier() = 0;
- virtual bool has_write_ref_pre_barrier() = 0;
- virtual bool has_write_prim_barrier() = 0;
-
- // These functions indicate whether a particular access of the given
- // kinds requires a barrier.
- virtual bool read_ref_needs_barrier(void* field) = 0;
- virtual bool read_prim_needs_barrier(HeapWord* field, size_t bytes) = 0;
- virtual bool write_prim_needs_barrier(HeapWord* field, size_t bytes,
- juint val1, juint val2) = 0;
-
- // The first four operations provide a direct implementation of the
- // barrier set. An interpreter loop, for example, could call these
- // directly, as appropriate.
-
- // Invoke the barrier, if any, necessary when reading the given ref field.
- virtual void read_ref_field(void* field) = 0;
-
- // Invoke the barrier, if any, necessary when reading the given primitive
- // "field" of "bytes" bytes in "obj".
- virtual void read_prim_field(HeapWord* field, size_t bytes) = 0;
-
- // Invoke the barrier, if any, necessary when writing "new_val" into the
- // ref field at "offset" in "obj".
- // (For efficiency reasons, this operation is specialized for certain
- // barrier types. Semantically, it should be thought of as a call to the
- // virtual "_work" function below, which must implement the barrier.)
- // First the pre-write versions...
- template <class T> inline void write_ref_field_pre(T* field, oop new_val);
-private:
- // Helper for write_ref_field_pre and friends, testing for specialized cases.
- bool devirtualize_reference_writes() const;
+ BarrierSetCodeGen* _code_gen;
+ C1BarrierSetCodeGen* _c1_code_gen;
+ C2BarrierSetCodeGen* _c2_code_gen;
- // Keep this private so as to catch violations at build time.
- virtual void write_ref_field_pre_work( void* field, oop new_val) { guarantee(false, "Not needed"); };
-protected:
- virtual void write_ref_field_pre_work( oop* field, oop new_val) {};
- virtual void write_ref_field_pre_work(narrowOop* field, oop new_val) {};
-public:
+ virtual BarrierSetCodeGen* make_code_gen() = 0;
+ virtual C1BarrierSetCodeGen* make_c1_code_gen() = 0;
+ virtual C2BarrierSetCodeGen* make_c2_code_gen() = 0;
- // ...then the post-write version.
- inline void write_ref_field(void* field, oop new_val, bool release = false);
-protected:
- virtual void write_ref_field_work(void* field, oop new_val, bool release) = 0;
public:
+ static BarrierSet* barrier_set() { return _bs; }
- // Invoke the barrier, if any, necessary when writing the "bytes"-byte
- // value(s) "val1" (and "val2") into the primitive "field".
- virtual void write_prim_field(HeapWord* field, size_t bytes,
- juint val1, juint val2) = 0;
-
- // Operations on arrays, or general regions (e.g., for "clone") may be
- // optimized by some barriers.
-
- // The first six operations tell whether such an optimization exists for
- // the particular barrier.
- virtual bool has_read_ref_array_opt() = 0;
- virtual bool has_read_prim_array_opt() = 0;
- virtual bool has_write_ref_array_pre_opt() { return true; }
- virtual bool has_write_ref_array_opt() = 0;
- virtual bool has_write_prim_array_opt() = 0;
-
- virtual bool has_read_region_opt() = 0;
- virtual bool has_write_region_opt() = 0;
-
- // These operations should assert false unless the corresponding operation
- // above returns true. Otherwise, they should perform an appropriate
- // barrier for an array whose elements are all in the given memory region.
- virtual void read_ref_array(MemRegion mr) = 0;
- virtual void read_prim_array(MemRegion mr) = 0;
-
- // Below length is the # array elements being written
- virtual void write_ref_array_pre(oop* dst, int length,
- bool dest_uninitialized = false) {}
- virtual void write_ref_array_pre(narrowOop* dst, int length,
- bool dest_uninitialized = false) {}
- // Below count is the # array elements being written, starting
- // at the address "start", which may not necessarily be HeapWord-aligned
- inline void write_ref_array(HeapWord* start, size_t count);
-
- // Static versions, suitable for calling from generated code;
- // count is # array elements being written, starting with "start",
- // which may not necessarily be HeapWord-aligned.
- static void static_write_ref_array_pre(HeapWord* start, size_t count);
- static void static_write_ref_array_post(HeapWord* start, size_t count);
+ // Print a description of the memory for the barrier set
+ virtual void print_on(outputStream* st) const = 0;
- virtual void write_ref_nmethod_pre(oop* dst, nmethod* nm) {}
- virtual void write_ref_nmethod_post(oop* dst, nmethod* nm) {}
+ virtual void initialize();
-protected:
- virtual void write_ref_array_work(MemRegion mr) = 0;
-public:
- virtual void write_prim_array(MemRegion mr) = 0;
+ BarrierSetCodeGen* code_gen() {
+ assert(_code_gen != NULL, "should be set");
+ return _code_gen;
+ }
+
+ C1BarrierSetCodeGen* c1_code_gen() {
+ assert(_c1_code_gen != NULL, "should be set");
+ return _c1_code_gen;
+ }
+
+ C2BarrierSetCodeGen* c2_code_gen() {
+ assert(_c2_code_gen != NULL, "should be set");
+ return _c2_code_gen;
+ }
+
+ // The AccessBarrier of a BarrierSet subclass is called by the Access API
+ // to perform decorated accesses.
+ template <DecoratorSet decorators>
+ class AccessBarrier: public BasicAccessBarrier<decorators> {
+ typedef BasicAccessBarrier<decorators> Basic;
+ public:
+ static void oop_store(void* addr, oop value);
+ static void oop_store_at(oop base, ptrdiff_t offset, oop value);
+ static void oop_store_at(nmethod* base, ptrdiff_t offset, oop value);
+ static void oop_store_at(Klass* base, ptrdiff_t offset, oop value);
- virtual void read_region(MemRegion mr) = 0;
+ static oop oop_load(void* addr);
+ static oop oop_load_at(oop base, ptrdiff_t offset);
- // (For efficiency reasons, this operation is specialized for certain
- // barrier types. Semantically, it should be thought of as a call to the
- // virtual "_work" function below, which must implement the barrier.)
- void write_region(MemRegion mr);
-protected:
- virtual void write_region_work(MemRegion mr) = 0;
-public:
- // Inform the BarrierSet that the the covered heap region that starts
- // with "base" has been changed to have the given size (possibly from 0,
- // for initialization.)
- virtual void resize_covered_region(MemRegion new_region) = 0;
-
- // If the barrier set imposes any alignment restrictions on boundaries
- // within the heap, this function tells whether they are met.
- virtual bool is_aligned(HeapWord* addr) = 0;
+ static oop oop_cas(oop new_value, void* addr, oop compare_value);
+ static oop oop_cas_at(oop new_value, oop base, ptrdiff_t offset, oop compare_value);
- // Print a description of the memory for the barrier set
- virtual void print_on(outputStream* st) const = 0;
+ static oop oop_swap(oop new_value, void* addr);
+ static oop oop_swap_at(oop new_value, oop base, ptrdiff_t offset);
+ };
+
+ // Support for optimizing compilers to call the barrier set on slow path allocations
+ // that did not enter a TLAB. Used for e.g. ReduceInitialCardMarks
+ virtual void on_slowpath_allocation(JavaThread* thread, oop new_obj) {}
+ virtual void on_add_thread(JavaThread* thread) {}
+ virtual void on_destroy_thread(JavaThread* thread) {}
+ virtual void make_parsable(JavaThread* thread) {}
+
+ // Resolve runtime paths for GC barriers accessible through the Access interface
+ // in runtime/access.hpp
+ template <DecoratorSet decorators, typename T, BarrierType barrier_type>
+ void* resolve_barrier();
+
+ template <DecoratorSet decorators>
+ void* resolve_clone_barrier();
};
+// Metafunction mapping a class derived from BarrierSet to the
+// corresponding Name enum tag.
+template<typename T> struct BSTypeToName;
+template<BarrierSet::Name T> struct BSNameToType;
+
template<typename T>
inline T* barrier_set_cast(BarrierSet* bs) {
- assert(bs->is_a(BarrierSet::GetName<T>::value), "wrong type of barrier set");
+ assert(bs->is_a(BSTypeToName<T>::value), "wrong type of barrier set");
return static_cast<T*>(bs);
}
#endif // SHARE_VM_GC_SHARED_BARRIERSET_HPP
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