2 * Copyright © 2010 Intel Corporation
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5 * copy of this software and associated documentation files (the "Software"),
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9 * Software is furnished to do so, subject to the following conditions:
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
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
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21 * DEALINGS IN THE SOFTWARE.
24 #include "main/core.h"
25 #include "glsl_symbol_table.h"
26 #include "glsl_parser_extras.h"
29 #include "program/hash_table.h"
32 static ir_function_signature
*
33 find_matching_signature(const char *name
, const exec_list
*actual_parameters
,
34 gl_shader
**shader_list
, unsigned num_shaders
);
36 class call_link_visitor
: public ir_hierarchical_visitor
{
38 call_link_visitor(gl_shader_program
*prog
, gl_shader
*linked
,
39 gl_shader
**shader_list
, unsigned num_shaders
)
42 this->shader_list
= shader_list
;
43 this->num_shaders
= num_shaders
;
45 this->linked
= linked
;
47 this->locals
= hash_table_ctor(0, hash_table_pointer_hash
,
48 hash_table_pointer_compare
);
53 hash_table_dtor(this->locals
);
56 virtual ir_visitor_status
visit(ir_variable
*ir
)
58 hash_table_insert(locals
, ir
, ir
);
59 return visit_continue
;
62 virtual ir_visitor_status
visit_enter(ir_call
*ir
)
64 /* If ir is an ir_call from a function that was imported from another
65 * shader callee will point to an ir_function_signature in the original
66 * shader. In this case the function signature MUST NOT BE MODIFIED.
67 * Doing so will modify the original shader. This may prevent that
68 * shader from being linkable in other programs.
70 const ir_function_signature
*const callee
= ir
->get_callee();
71 assert(callee
!= NULL
);
72 const char *const name
= callee
->function_name();
74 /* Determine if the requested function signature already exists in the
75 * final linked shader. If it does, use it as the target of the call.
77 ir_function_signature
*sig
=
78 find_matching_signature(name
, &callee
->parameters
, &linked
, 1);
81 return visit_continue
;
84 /* Try to find the signature in one of the other shaders that is being
85 * linked. If it's not found there, return an error.
87 sig
= find_matching_signature(name
, &ir
->actual_parameters
, shader_list
,
90 /* FINISHME: Log the full signature of unresolved function.
92 linker_error_printf(this->prog
, "unresolved reference to function "
94 this->success
= false;
98 /* Find the prototype information in the linked shader. Generate any
99 * details that may be missing.
101 ir_function
*f
= linked
->symbols
->get_function(name
);
103 f
= new(linked
) ir_function(name
);
105 /* Add the new function to the linked IR.
107 linked
->symbols
->add_function(f
);
108 linked
->ir
->push_head(f
);
111 ir_function_signature
*linked_sig
=
112 f
->exact_matching_signature(&callee
->parameters
);
113 if (linked_sig
== NULL
) {
114 linked_sig
= new(linked
) ir_function_signature(callee
->return_type
);
115 f
->add_signature(linked_sig
);
118 /* At this point linked_sig and called may be the same. If ir is an
119 * ir_call from linked then linked_sig and callee will be
120 * ir_function_signatures that have no definitions (is_defined is false).
122 assert(!linked_sig
->is_defined
);
123 assert(linked_sig
->body
.is_empty());
125 /* Create an in-place clone of the function definition. This multistep
126 * process introduces some complexity here, but it has some advantages.
127 * The parameter list and the and function body are cloned separately.
128 * The clone of the parameter list is used to prime the hashtable used
129 * to replace variable references in the cloned body.
131 * The big advantage is that the ir_function_signature does not change.
132 * This means that we don't have to process the rest of the IR tree to
133 * patch ir_call nodes. In addition, there is no way to remove or
134 * replace signature stored in a function. One could easily be added,
135 * but this avoids the need.
137 struct hash_table
*ht
= hash_table_ctor(0, hash_table_pointer_hash
,
138 hash_table_pointer_compare
);
139 exec_list formal_parameters
;
140 foreach_list_const(node
, &sig
->parameters
) {
141 const ir_instruction
*const original
= (ir_instruction
*) node
;
142 assert(const_cast<ir_instruction
*>(original
)->as_variable());
144 ir_instruction
*copy
= original
->clone(linked
, ht
);
145 formal_parameters
.push_tail(copy
);
148 linked_sig
->replace_parameters(&formal_parameters
);
150 foreach_list_const(node
, &sig
->body
) {
151 const ir_instruction
*const original
= (ir_instruction
*) node
;
153 ir_instruction
*copy
= original
->clone(linked
, ht
);
154 linked_sig
->body
.push_tail(copy
);
157 linked_sig
->is_defined
= true;
160 /* Patch references inside the function to things outside the function
161 * (i.e., function calls and global variables).
163 linked_sig
->accept(this);
165 ir
->set_callee(linked_sig
);
167 return visit_continue
;
170 virtual ir_visitor_status
visit(ir_dereference_variable
*ir
)
172 if (hash_table_find(locals
, ir
->var
) == NULL
) {
173 /* The non-function variable must be a global, so try to find the
174 * variable in the shader's symbol table. If the variable is not
175 * found, then it's a global that *MUST* be defined in the original
178 ir_variable
*var
= linked
->symbols
->get_variable(ir
->var
->name
);
180 /* Clone the ir_variable that the dereference already has and add
181 * it to the linked shader.
183 var
= ir
->var
->clone(linked
, NULL
);
184 linked
->symbols
->add_variable(var
);
185 linked
->ir
->push_head(var
);
186 } else if (var
->type
->is_array()) {
187 /* It is possible to have a global array declared in multiple
188 * shaders without a size. The array is implicitly sized by the
189 * maximal access to it in *any* shader. Because of this, we
190 * need to track the maximal access to the array as linking pulls
191 * more functions in that access the array.
193 var
->max_array_access
=
194 MAX2(var
->max_array_access
, ir
->var
->max_array_access
);
196 if (var
->type
->length
== 0 && ir
->var
->type
->length
!= 0)
197 var
->type
= ir
->var
->type
;
203 return visit_continue
;
206 /** Was function linking successful? */
211 * Shader program being linked
213 * This is only used for logging error messages.
215 gl_shader_program
*prog
;
217 /** List of shaders available for linking. */
218 gl_shader
**shader_list
;
220 /** Number of shaders available for linking. */
221 unsigned num_shaders
;
224 * Final linked shader
226 * This is used two ways. It is used to find global variables in the
227 * linked shader that are accessed by the function. It is also used to add
228 * global variables from the shader where the function originated.
233 * Table of variables local to the function.
240 * Searches a list of shaders for a particular function definition
242 ir_function_signature
*
243 find_matching_signature(const char *name
, const exec_list
*actual_parameters
,
244 gl_shader
**shader_list
, unsigned num_shaders
)
246 for (unsigned i
= 0; i
< num_shaders
; i
++) {
247 ir_function
*const f
= shader_list
[i
]->symbols
->get_function(name
);
252 ir_function_signature
*sig
= f
->matching_signature(actual_parameters
);
254 if ((sig
== NULL
) || !sig
->is_defined
)
265 link_function_calls(gl_shader_program
*prog
, gl_shader
*main
,
266 gl_shader
**shader_list
, unsigned num_shaders
)
268 call_link_visitor
v(prog
, main
, shader_list
, num_shaders
);