xref: /aosp_15_r20/external/mesa3d/src/compiler/glsl/ir_array_refcount.h (revision 6104692788411f58d303aa86923a9ff6ecaded22)
1 /*
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9  * Software is furnished to do so, subject to the following conditions:
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11  * The above copyright notice and this permission notice (including the next
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16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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23 
24 /**
25  * \file ir_array_refcount.h
26  *
27  * Provides a visitor which produces a list of variables referenced.
28  */
29 
30 #ifndef GLSL_IR_ARRAY_REFCOUNT_H
31 #define GLSL_IR_ARRAY_REFCOUNT_H
32 
33 #include "ir.h"
34 #include "ir_visitor.h"
35 #include "linker_util.h"
36 #include "compiler/glsl_types.h"
37 #include "util/bitset.h"
38 
39 class ir_array_refcount_entry
40 {
41 public:
42    ir_array_refcount_entry(ir_variable *var);
43    ir_array_refcount_entry(const ir_array_refcount_entry &) = delete;
44    ~ir_array_refcount_entry();
45    ir_array_refcount_entry & operator=(const ir_array_refcount_entry &) = delete;
46 
47    ir_variable *var; /* The key: the variable's pointer. */
48 
49    /** Has the variable been referenced? */
50    bool is_referenced;
51 
52    /** Count of nested arrays in the type. */
53    unsigned array_depth;
54 
55    /** Set of bit-flags to note which array elements have been accessed. */
56    BITSET_WORD *bits;
57 
58    /** Has a linearized array index been referenced? */
is_linearized_index_referenced(unsigned linearized_index)59    bool is_linearized_index_referenced(unsigned linearized_index) const
60    {
61       assert(bits != 0);
62       assert(linearized_index <= num_bits);
63 
64       return BITSET_TEST(bits, linearized_index);
65    }
66 
67 private:
68 
69    /**
70     * Total number of bits referenced by \c bits.
71     *
72     * Also the total number of array(s-of-arrays) elements of \c var.
73     */
74    unsigned num_bits;
75 
76    friend class array_refcount_test;
77 };
78 
79 class ir_array_refcount_visitor : public ir_hierarchical_visitor {
80 public:
81    ir_array_refcount_visitor(void);
82    ~ir_array_refcount_visitor(void);
83 
84    virtual ir_visitor_status visit(ir_dereference_variable *);
85 
86    virtual ir_visitor_status visit_enter(ir_function_signature *);
87    virtual ir_visitor_status visit_enter(ir_dereference_array *);
88 
89    /**
90     * Find variable in the hash table, and insert it if not present
91     */
92    ir_array_refcount_entry *get_variable_entry(ir_variable *var);
93 
94    /**
95     * Hash table mapping ir_variable to ir_array_refcount_entry.
96     */
97    struct hash_table *ht;
98 
99    void *mem_ctx;
100 
101 private:
102    /** Get an array_deref_range element from private tracking. */
103    array_deref_range *get_array_deref();
104 
105    /**
106     * Last ir_dereference_array that was visited
107     *
108     * Used to prevent some redundant calculations.
109     *
110     * \sa ::visit_enter(ir_dereference_array *)
111     */
112    ir_dereference_array *last_array_deref;
113 
114    /**
115     * \name array_deref_range tracking
116     */
117    /*@{*/
118    /** Currently allocated block of derefs. */
119    array_deref_range *derefs;
120 
121    /** Number of derefs used in current processing. */
122    unsigned num_derefs;
123 
124    /** Size of the derefs buffer in bytes. */
125    unsigned derefs_size;
126    /*@}*/
127 };
128 
129 #endif /* GLSL_IR_ARRAY_REFCOUNT_H */
130