1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
|
/*
* Copyright © 2016 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
/**
* \file ir_array_refcount.h
*
* Provides a visitor which produces a list of variables referenced.
*/
#include "ir.h"
#include "ir_visitor.h"
#include "compiler/glsl_types.h"
#include "util/bitset.h"
/**
* Describes an access of an array element or an access of the whole array
*/
struct array_deref_range {
/**
* Index that was accessed.
*
* All valid array indices are less than the size of the array. If index
* is equal to the size of the array, this means the entire array has been
* accessed (e.g., due to use of a non-constant index).
*/
unsigned index;
/** Size of the array. Used for offset calculations. */
unsigned size;
};
class ir_array_refcount_entry
{
public:
ir_array_refcount_entry(ir_variable *var);
~ir_array_refcount_entry();
ir_variable *var; /* The key: the variable's pointer. */
/** Has the variable been referenced? */
bool is_referenced;
/**
* Mark a set of array elements as accessed.
*
* If every \c array_deref_range is for a single index, only a single
* element will be marked. If any \c array_deref_range is for an entire
* array-of-, then multiple elements will be marked.
*
* Items in the \c array_deref_range list appear in least- to
* most-significant order. This is the \b opposite order the indices
* appear in the GLSL shader text. An array access like
*
* x = y[1][i][3];
*
* would appear as
*
* { { 3, n }, { m, m }, { 1, p } }
*
* where n, m, and p are the sizes of the arrays-of-arrays.
*
* The set of marked array elements can later be queried by
* \c ::is_linearized_index_referenced.
*
* \param dr List of array_deref_range elements to be processed.
* \param count Number of array_deref_range elements to be processed.
*/
void mark_array_elements_referenced(const array_deref_range *dr,
unsigned count);
/** Has a linearized array index been referenced? */
bool is_linearized_index_referenced(unsigned linearized_index) const
{
assert(bits != 0);
assert(linearized_index <= num_bits);
return BITSET_TEST(bits, linearized_index);
}
private:
/** Set of bit-flags to note which array elements have been accessed. */
BITSET_WORD *bits;
/**
* Total number of bits referenced by \c bits.
*
* Also the total number of array(s-of-arrays) elements of \c var.
*/
unsigned num_bits;
/** Count of nested arrays in the type. */
unsigned array_depth;
/**
* Recursive part of the public mark_array_elements_referenced method.
*
* The recursion occurs when an entire array-of- is accessed. See the
* implementation for more details.
*
* \param dr List of array_deref_range elements to be
* processed.
* \param count Number of array_deref_range elements to be
* processed.
* \param scale Current offset scale.
* \param linearized_index Current accumulated linearized array index.
*/
void mark_array_elements_referenced(const array_deref_range *dr,
unsigned count,
unsigned scale,
unsigned linearized_index);
friend class array_refcount_test;
};
class ir_array_refcount_visitor : public ir_hierarchical_visitor {
public:
ir_array_refcount_visitor(void);
~ir_array_refcount_visitor(void);
virtual ir_visitor_status visit(ir_dereference_variable *);
virtual ir_visitor_status visit_enter(ir_function_signature *);
/**
* Find variable in the hash table, and insert it if not present
*/
ir_array_refcount_entry *get_variable_entry(ir_variable *var);
/**
* Hash table mapping ir_variable to ir_array_refcount_entry.
*/
struct hash_table *ht;
void *mem_ctx;
private:
/** Get an array_deref_range element from private tracking. */
array_deref_range *get_array_deref();
/**
* \name array_deref_range tracking
*/
/*@{*/
/** Currently allocated block of derefs. */
array_deref_range *derefs;
/** Number of derefs used in current processing. */
unsigned num_derefs;
/** Size of the derefs buffer in bytes. */
unsigned derefs_size;
/*@}*/
};
|
