1/*
2 * Copyright © 2016 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 */
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
39class ir_array_refcount_entry
40{
41public:
42   ir_array_refcount_entry(ir_variable *var);
43   ~ir_array_refcount_entry();
44
45   ir_variable *var; /* The key: the variable's pointer. */
46
47   /** Has the variable been referenced? */
48   bool is_referenced;
49
50   /** Count of nested arrays in the type. */
51   unsigned array_depth;
52
53   /** Set of bit-flags to note which array elements have been accessed. */
54   BITSET_WORD *bits;
55
56   /** Has a linearized array index been referenced? */
57   bool is_linearized_index_referenced(unsigned linearized_index) const
58   {
59      assert(bits != 0);
60      assert(linearized_index <= num_bits);
61
62      return BITSET_TEST(bits, linearized_index);
63   }
64
65private:
66
67   /**
68    * Total number of bits referenced by \c bits.
69    *
70    * Also the total number of array(s-of-arrays) elements of \c var.
71    */
72   unsigned num_bits;
73
74   friend class array_refcount_test;
75};
76
77class ir_array_refcount_visitor : public ir_hierarchical_visitor {
78public:
79   ir_array_refcount_visitor(void);
80   ~ir_array_refcount_visitor(void);
81
82   virtual ir_visitor_status visit(ir_dereference_variable *);
83
84   virtual ir_visitor_status visit_enter(ir_function_signature *);
85   virtual ir_visitor_status visit_enter(ir_dereference_array *);
86
87   /**
88    * Find variable in the hash table, and insert it if not present
89    */
90   ir_array_refcount_entry *get_variable_entry(ir_variable *var);
91
92   /**
93    * Hash table mapping ir_variable to ir_array_refcount_entry.
94    */
95   struct hash_table *ht;
96
97   void *mem_ctx;
98
99private:
100   /** Get an array_deref_range element from private tracking. */
101   array_deref_range *get_array_deref();
102
103   /**
104    * Last ir_dereference_array that was visited
105    *
106    * Used to prevent some redundant calculations.
107    *
108    * \sa ::visit_enter(ir_dereference_array *)
109    */
110   ir_dereference_array *last_array_deref;
111
112   /**
113    * \name array_deref_range tracking
114    */
115   /*@{*/
116   /** Currently allocated block of derefs. */
117   array_deref_range *derefs;
118
119   /** Number of derefs used in current processing. */
120   unsigned num_derefs;
121
122   /** Size of the derefs buffer in bytes. */
123   unsigned derefs_size;
124   /*@}*/
125};
126
127#endif /* GLSL_IR_ARRAY_REFCOUNT_H */
128