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
|
/*
* Copyright © 2010 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 opt_dead_functions.cpp
*
* Eliminates unused functions from the linked program.
*/
#include "ir.h"
#include "ir_visitor.h"
#include "ir_expression_flattening.h"
#include "glsl_types.h"
namespace {
class signature_entry : public exec_node
{
public:
signature_entry(ir_function_signature *sig)
{
this->signature = sig;
this->used = false;
}
ir_function_signature *signature;
bool used;
};
class ir_dead_functions_visitor : public ir_hierarchical_visitor {
public:
ir_dead_functions_visitor()
{
this->mem_ctx = ralloc_context(NULL);
}
~ir_dead_functions_visitor()
{
ralloc_free(this->mem_ctx);
}
virtual ir_visitor_status visit_enter(ir_function_signature *);
virtual ir_visitor_status visit_enter(ir_call *);
signature_entry *get_signature_entry(ir_function_signature *var);
/* List of signature_entry */
exec_list signature_list;
void *mem_ctx;
};
} /* unnamed namespace */
signature_entry *
ir_dead_functions_visitor::get_signature_entry(ir_function_signature *sig)
{
foreach_list(n, &this->signature_list) {
signature_entry *entry = (signature_entry *) n;
if (entry->signature == sig)
return entry;
}
signature_entry *entry = new(mem_ctx) signature_entry(sig);
this->signature_list.push_tail(entry);
return entry;
}
ir_visitor_status
ir_dead_functions_visitor::visit_enter(ir_function_signature *ir)
{
signature_entry *entry = this->get_signature_entry(ir);
if (strcmp(ir->function_name(), "main") == 0) {
entry->used = true;
}
return visit_continue;
}
ir_visitor_status
ir_dead_functions_visitor::visit_enter(ir_call *ir)
{
signature_entry *entry = this->get_signature_entry(ir->callee);
entry->used = true;
return visit_continue;
}
bool
do_dead_functions(exec_list *instructions)
{
ir_dead_functions_visitor v;
bool progress = false;
visit_list_elements(&v, instructions);
/* Now that we've figured out which function signatures are used, remove
* the unused ones, and remove function definitions that have no more
* signatures.
*/
foreach_iter(exec_list_iterator, iter, v.signature_list) {
signature_entry *entry = (signature_entry *)iter.get();
if (!entry->used) {
entry->signature->remove();
delete entry->signature;
progress = true;
}
delete(entry);
}
/* We don't just do this above when we nuked a signature because of
* const pointers.
*/
foreach_iter(exec_list_iterator, iter, *instructions) {
ir_instruction *ir = (ir_instruction *)iter.get();
ir_function *func = ir->as_function();
if (func && func->signatures.is_empty()) {
/* At this point (post-linking), the symbol table is no
* longer in use, so not removing the function from the
* symbol table should be OK.
*/
func->remove();
delete func;
progress = true;
}
}
return progress;
}
|
