8225770: ZGC: C2: Generates on_weak instead of on_strong barriers
Reviewed-by: neliasso, eosterlund
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#ifndef SHARE_GC_Z_C2_ZBARRIERSETC2_HPP
#define SHARE_GC_Z_C2_ZBARRIERSETC2_HPP
#include "gc/shared/c2/barrierSetC2.hpp"
#include "memory/allocation.hpp"
#include "opto/node.hpp"
#include "utilities/growableArray.hpp"
class ZCompareAndSwapPNode : public CompareAndSwapPNode {
public:
ZCompareAndSwapPNode(Node* c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : CompareAndSwapPNode(c, mem, adr, val, ex, mem_ord) { }
virtual int Opcode() const;
};
class ZWeakCompareAndSwapPNode : public WeakCompareAndSwapPNode {
public:
ZWeakCompareAndSwapPNode(Node* c, Node *mem, Node *adr, Node *val, Node *ex, MemNode::MemOrd mem_ord) : WeakCompareAndSwapPNode(c, mem, adr, val, ex, mem_ord) { }
virtual int Opcode() const;
};
class ZCompareAndExchangePNode : public CompareAndExchangePNode {
public:
ZCompareAndExchangePNode(Node* c, Node *mem, Node *adr, Node *val, Node *ex, const TypePtr* at, const Type* t, MemNode::MemOrd mem_ord) : CompareAndExchangePNode(c, mem, adr, val, ex, at, t, mem_ord) { }
virtual int Opcode() const;
};
class ZGetAndSetPNode : public GetAndSetPNode {
public:
ZGetAndSetPNode(Node* c, Node *mem, Node *adr, Node *val, const TypePtr* at, const Type* t) : GetAndSetPNode(c, mem, adr, val, at, t) { }
virtual int Opcode() const;
};
class LoadBarrierNode : public MultiNode {
private:
bool _weak; // On strong or weak oop reference
static bool is_dominator(PhaseIdealLoop* phase, bool linear_only, Node *d, Node *n);
void push_dominated_barriers(PhaseIterGVN* igvn) const;
public:
enum {
Control,
Memory,
Oop,
Address,
Number_of_Outputs = Address,
Similar,
Number_of_Inputs
};
LoadBarrierNode(Compile* C,
Node* c,
Node* mem,
Node* val,
Node* adr,
bool weak);
virtual int Opcode() const;
virtual uint size_of() const;
virtual bool cmp(const Node& n) const;
virtual const Type *bottom_type() const;
virtual const TypePtr* adr_type() const;
virtual const Type *Value(PhaseGVN *phase) const;
virtual Node *Identity(PhaseGVN *phase);
virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
virtual uint match_edge(uint idx) const;
LoadBarrierNode* has_dominating_barrier(PhaseIdealLoop* phase,
bool linear_only,
bool look_for_similar);
void fix_similar_in_uses(PhaseIterGVN* igvn);
bool has_true_uses() const;
bool can_be_eliminated() const {
return !in(Similar)->is_top();
}
bool is_weak() const {
return _weak;
}
};
class LoadBarrierSlowRegNode : public TypeNode {
private:
bool _is_weak;
public:
LoadBarrierSlowRegNode(Node *c,
Node *adr,
Node *src,
const TypePtr* t,
bool weak) :
TypeNode(t, 3), _is_weak(weak) {
init_req(1, adr);
init_req(2, src);
init_class_id(Class_LoadBarrierSlowReg);
}
virtual uint size_of() const {
return sizeof(*this);
}
virtual const char * name() {
return "LoadBarrierSlowRegNode";
}
virtual Node *Ideal(PhaseGVN *phase, bool can_reshape) {
return NULL;
}
virtual int Opcode() const;
bool is_weak() { return _is_weak; }
};
class ZBarrierSetC2State : public ResourceObj {
private:
// List of load barrier nodes which need to be expanded before matching
GrowableArray<LoadBarrierNode*>* _load_barrier_nodes;
public:
ZBarrierSetC2State(Arena* comp_arena);
int load_barrier_count() const;
void add_load_barrier_node(LoadBarrierNode* n);
void remove_load_barrier_node(LoadBarrierNode* n);
LoadBarrierNode* load_barrier_node(int idx) const;
};
class ZBarrierSetC2 : public BarrierSetC2 {
private:
ZBarrierSetC2State* state() const;
void expand_loadbarrier_node(PhaseMacroExpand* phase, LoadBarrierNode* barrier) const;
#ifdef ASSERT
void verify_gc_barriers(bool post_parse) const;
#endif
protected:
virtual Node* load_at_resolved(C2Access& access, const Type* val_type) const;
virtual Node* atomic_cmpxchg_val_at_resolved(C2AtomicParseAccess& access,
Node* expected_val,
Node* new_val,
const Type* val_type) const;
virtual Node* atomic_cmpxchg_bool_at_resolved(C2AtomicParseAccess& access,
Node* expected_val,
Node* new_val,
const Type* value_type) const;
virtual Node* atomic_xchg_at_resolved(C2AtomicParseAccess& access,
Node* new_val,
const Type* val_type) const;
public:
virtual void* create_barrier_state(Arena* comp_arena) const;
virtual bool has_load_barriers() const { return true; }
virtual bool is_gc_barrier_node(Node* node) const;
virtual Node* step_over_gc_barrier(Node* c) const;
virtual Node* step_over_gc_barrier_ctrl(Node* c) const;
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(PhaseIterGVN* igvn, Node* node) const;
virtual void eliminate_useless_gc_barriers(Unique_Node_List &useful, Compile* C) const;
virtual bool array_copy_requires_gc_barriers(bool tightly_coupled_alloc, BasicType type, bool is_clone, ArrayCopyPhase phase) const;
virtual bool expand_barriers(Compile* C, PhaseIterGVN& igvn) const;
virtual bool final_graph_reshaping(Compile* compile, Node* n, uint opcode) const;
virtual bool matcher_find_shared_visit(Matcher* matcher, Matcher::MStack& mstack, Node* n, uint opcode, bool& mem_op, int& mem_addr_idx) const;
virtual bool matcher_find_shared_post_visit(Matcher* matcher, Node* n, uint opcode) const;
virtual bool needs_anti_dependence_check(const Node* node) const;
#ifdef ASSERT
virtual void verify_gc_barriers(Compile* compile, CompilePhase phase) const;
#endif
// Load barrier insertion and expansion external
virtual void barrier_insertion_phase(Compile* C, PhaseIterGVN &igvn) const;
virtual bool optimize_loops(PhaseIdealLoop* phase, LoopOptsMode mode, VectorSet& visited, Node_Stack& nstack, Node_List& worklist) const;
virtual bool is_gc_specific_loop_opts_pass(LoopOptsMode mode) const { return (mode == LoopOptsZBarrierInsertion); }
private:
// Load barrier insertion and expansion internal
void insert_barriers_on_unsafe(PhaseIdealLoop* phase) const;
void clean_catch_blocks(PhaseIdealLoop* phase) const;
void insert_load_barriers(PhaseIdealLoop* phase) const;
LoadNode* insert_one_loadbarrier(PhaseIdealLoop* phase, LoadNode* load, Node* ctrl) const;
void insert_one_loadbarrier_inner(PhaseIdealLoop* phase, LoadNode* load, Node* ctrl, VectorSet visited) const;
};
#endif // SHARE_GC_Z_C2_ZBARRIERSETC2_HPP