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24 
25 #ifndef SHARE_OPTO_REGALLOC_HPP
26 #define SHARE_OPTO_REGALLOC_HPP
27 
28 #include "code/vmreg.hpp"
29 #include "opto/block.hpp"
30 #include "opto/matcher.hpp"
31 #include "opto/phase.hpp"
32 
33 class Node;
34 class Matcher;
35 class PhaseCFG;
36 
37 #define  MAX_REG_ALLOCATORS   10
38 
39 //------------------------------PhaseRegAlloc------------------------------------
40 // Abstract register allocator
41 class PhaseRegAlloc : public Phase {
42   friend class VMStructs;
43   static void (*_alloc_statistics[MAX_REG_ALLOCATORS])();
44   static int _num_allocators;
45 
46 protected:
47   OptoRegPair  *_node_regs;
48   uint         _node_regs_max_index;
49   VectorSet    _node_oops;         // Mapping from node indices to oopiness
50 
51   void alloc_node_regs(int size);  // allocate _node_regs table with at least "size" elements
52 
53   PhaseRegAlloc( uint unique, PhaseCFG &cfg, Matcher &matcher,
54                  void (*pr_stats)());
55 public:
56   PhaseCFG &_cfg;               // Control flow graph
57   uint _framesize;              // Size of frame in stack-slots. not counting preserve area
58   OptoReg::Name _max_reg;       // Past largest register seen
59   Matcher &_matcher;            // Convert Ideal to MachNodes
node_regs_max_index() const60   uint node_regs_max_index() const { return _node_regs_max_index; }
61 
62   // Get the register associated with the Node
get_reg_first(const Node * n) const63   OptoReg::Name get_reg_first( const Node *n ) const {
64     debug_only( if( n->_idx >= _node_regs_max_index ) n->dump(); );
65     assert( n->_idx < _node_regs_max_index, "Exceeded _node_regs array");
66     return _node_regs[n->_idx].first();
67   }
get_reg_second(const Node * n) const68   OptoReg::Name get_reg_second( const Node *n ) const {
69     debug_only( if( n->_idx >= _node_regs_max_index ) n->dump(); );
70     assert( n->_idx < _node_regs_max_index, "Exceeded _node_regs array");
71     return _node_regs[n->_idx].second();
72   }
73 
74   // Do all the real work of allocate
75   virtual void Register_Allocate() = 0;
76 
77 
78   // notify the register allocator that "node" is a new reference
79   // to the value produced by "old_node"
80   virtual void add_reference( const Node *node, const Node *old_node) = 0;
81 
82 
83   // Set the register associated with a new Node
set_bad(uint idx)84   void set_bad( uint idx ) {
85     assert( idx < _node_regs_max_index, "Exceeded _node_regs array");
86     _node_regs[idx].set_bad();
87   }
set1(uint idx,OptoReg::Name reg)88   void set1( uint idx, OptoReg::Name reg ) {
89     assert( idx < _node_regs_max_index, "Exceeded _node_regs array");
90     _node_regs[idx].set1(reg);
91   }
set2(uint idx,OptoReg::Name reg)92   void set2( uint idx, OptoReg::Name reg ) {
93     assert( idx < _node_regs_max_index, "Exceeded _node_regs array");
94     _node_regs[idx].set2(reg);
95   }
set_pair(uint idx,OptoReg::Name hi,OptoReg::Name lo)96   void set_pair( uint idx, OptoReg::Name hi, OptoReg::Name lo ) {
97     assert( idx < _node_regs_max_index, "Exceeded _node_regs array");
98     _node_regs[idx].set_pair(hi, lo);
99   }
set_ptr(uint idx,OptoReg::Name reg)100   void set_ptr( uint idx, OptoReg::Name reg ) {
101     assert( idx < _node_regs_max_index, "Exceeded _node_regs array");
102     _node_regs[idx].set_ptr(reg);
103   }
104   // Set and query if a node produces an oop
105   void set_oop( const Node *n, bool );
106   bool is_oop( const Node *n ) const;
107 
108   // Convert a register number to a stack offset
109   int reg2offset          ( OptoReg::Name reg ) const;
110   int reg2offset_unchecked( OptoReg::Name reg ) const;
111 
112   // Convert a stack offset to a register number
113   OptoReg::Name offset2reg( int stk_offset ) const;
114 
115   // Get the register encoding associated with the Node
get_encode(const Node * n) const116   int get_encode(const Node *n) const {
117     assert( n->_idx < _node_regs_max_index, "Exceeded _node_regs array");
118     OptoReg::Name first = _node_regs[n->_idx].first();
119     OptoReg::Name second = _node_regs[n->_idx].second();
120     assert( !OptoReg::is_valid(second) || second == first+1, "" );
121     assert(OptoReg::is_reg(first), "out of range");
122     return Matcher::_regEncode[first];
123   }
124 
125 #ifndef PRODUCT
126   static int _total_framesize;
127   static int _max_framesize;
128 
129   virtual void dump_frame() const = 0;
130   virtual char *dump_register( const Node *n, char *buf  ) const = 0;
131   static void print_statistics();
132 #endif
133 };
134 
135 #endif // SHARE_OPTO_REGALLOC_HPP
136