2 * Copyright © 2010 Intel Corporation
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:
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
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.
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
,
37 class call_link_visitor
: public ir_hierarchical_visitor
{
39 call_link_visitor(gl_shader_program
*prog
, gl_shader
*linked
,
40 gl_shader
**shader_list
, unsigned num_shaders
)
43 this->shader_list
= shader_list
;
44 this->num_shaders
= num_shaders
;
46 this->linked
= linked
;
48 this->locals
= hash_table_ctor(0, hash_table_pointer_hash
,
49 hash_table_pointer_compare
);
54 hash_table_dtor(this->locals
);
57 virtual ir_visitor_status
visit(ir_variable
*ir
)
59 hash_table_insert(locals
, ir
, ir
);
60 return visit_continue
;
63 virtual ir_visitor_status
visit_enter(ir_call
*ir
)
65 /* If ir is an ir_call from a function that was imported from another
66 * shader callee will point to an ir_function_signature in the original
67 * shader. In this case the function signature MUST NOT BE MODIFIED.
68 * Doing so will modify the original shader. This may prevent that
69 * shader from being linkable in other programs.
71 const ir_function_signature
*const callee
= ir
->callee
;
72 assert(callee
!= NULL
);
73 const char *const name
= callee
->function_name();
75 /* Determine if the requested function signature already exists in the
76 * final linked shader. If it does, use it as the target of the call.
78 ir_function_signature
*sig
=
79 find_matching_signature(name
, &callee
->parameters
, &linked
, 1,
83 return visit_continue
;
86 /* Try to find the signature in one of the other shaders that is being
87 * linked. If it's not found there, return an error.
89 sig
= find_matching_signature(name
, &ir
->actual_parameters
, shader_list
,
90 num_shaders
, ir
->use_builtin
);
92 /* FINISHME: Log the full signature of unresolved function.
94 linker_error(this->prog
, "unresolved reference to function `%s'\n",
96 this->success
= false;
100 /* Find the prototype information in the linked shader. Generate any
101 * details that may be missing.
103 ir_function
*f
= linked
->symbols
->get_function(name
);
105 f
= new(linked
) ir_function(name
);
107 /* Add the new function to the linked IR. Put it at the end
108 * so that it comes after any global variable declarations
111 linked
->symbols
->add_function(f
);
112 linked
->ir
->push_tail(f
);
115 ir_function_signature
*linked_sig
=
116 f
->exact_matching_signature(&callee
->parameters
);
117 if ((linked_sig
== NULL
)
118 || ((linked_sig
!= NULL
)
119 && (linked_sig
->is_builtin() != ir
->use_builtin
))) {
120 linked_sig
= new(linked
) ir_function_signature(callee
->return_type
);
121 f
->add_signature(linked_sig
);
124 /* At this point linked_sig and called may be the same. If ir is an
125 * ir_call from linked then linked_sig and callee will be
126 * ir_function_signatures that have no definitions (is_defined is false).
128 assert(!linked_sig
->is_defined
);
129 assert(linked_sig
->body
.is_empty());
131 /* Create an in-place clone of the function definition. This multistep
132 * process introduces some complexity here, but it has some advantages.
133 * The parameter list and the and function body are cloned separately.
134 * The clone of the parameter list is used to prime the hashtable used
135 * to replace variable references in the cloned body.
137 * The big advantage is that the ir_function_signature does not change.
138 * This means that we don't have to process the rest of the IR tree to
139 * patch ir_call nodes. In addition, there is no way to remove or
140 * replace signature stored in a function. One could easily be added,
141 * but this avoids the need.
143 struct hash_table
*ht
= hash_table_ctor(0, hash_table_pointer_hash
,
144 hash_table_pointer_compare
);
145 exec_list formal_parameters
;
146 foreach_list_const(node
, &sig
->parameters
) {
147 const ir_instruction
*const original
= (ir_instruction
*) node
;
148 assert(const_cast<ir_instruction
*>(original
)->as_variable());
150 ir_instruction
*copy
= original
->clone(linked
, ht
);
151 formal_parameters
.push_tail(copy
);
154 linked_sig
->replace_parameters(&formal_parameters
);
156 foreach_list_const(node
, &sig
->body
) {
157 const ir_instruction
*const original
= (ir_instruction
*) node
;
159 ir_instruction
*copy
= original
->clone(linked
, ht
);
160 linked_sig
->body
.push_tail(copy
);
163 linked_sig
->is_defined
= true;
166 /* Patch references inside the function to things outside the function
167 * (i.e., function calls and global variables).
169 linked_sig
->accept(this);
171 ir
->callee
= linked_sig
;
173 return visit_continue
;
176 virtual ir_visitor_status
visit_leave(ir_call
*ir
)
178 /* Traverse list of function parameters, and for array parameters
179 * propagate max_array_access. Otherwise arrays that are only referenced
180 * from inside functions via function parameters will be incorrectly
181 * optimized. This will lead to incorrect code being generated (or worse).
182 * Do it when leaving the node so the children would propagate their
183 * array accesses first.
186 const exec_node
*formal_param_node
= ir
->callee
->parameters
.get_head();
187 if (formal_param_node
) {
188 const exec_node
*actual_param_node
= ir
->actual_parameters
.get_head();
189 while (!actual_param_node
->is_tail_sentinel()) {
190 ir_variable
*formal_param
= (ir_variable
*) formal_param_node
;
191 ir_rvalue
*actual_param
= (ir_rvalue
*) actual_param_node
;
193 formal_param_node
= formal_param_node
->get_next();
194 actual_param_node
= actual_param_node
->get_next();
196 if (formal_param
->type
->is_array()) {
197 ir_dereference_variable
*deref
= actual_param
->as_dereference_variable();
198 if (deref
&& deref
->var
&& deref
->var
->type
->is_array()) {
199 deref
->var
->max_array_access
=
200 MAX2(formal_param
->max_array_access
, deref
->var
->max_array_access
);
205 return visit_continue
;
208 virtual ir_visitor_status
visit(ir_dereference_variable
*ir
)
210 if (hash_table_find(locals
, ir
->var
) == NULL
) {
211 /* The non-function variable must be a global, so try to find the
212 * variable in the shader's symbol table. If the variable is not
213 * found, then it's a global that *MUST* be defined in the original
216 ir_variable
*var
= linked
->symbols
->get_variable(ir
->var
->name
);
218 /* Clone the ir_variable that the dereference already has and add
219 * it to the linked shader.
221 var
= ir
->var
->clone(linked
, NULL
);
222 linked
->symbols
->add_variable(var
);
223 linked
->ir
->push_head(var
);
224 } else if (var
->type
->is_array()) {
225 /* It is possible to have a global array declared in multiple
226 * shaders without a size. The array is implicitly sized by the
227 * maximal access to it in *any* shader. Because of this, we
228 * need to track the maximal access to the array as linking pulls
229 * more functions in that access the array.
231 var
->max_array_access
=
232 MAX2(var
->max_array_access
, ir
->var
->max_array_access
);
234 if (var
->type
->length
== 0 && ir
->var
->type
->length
!= 0)
235 var
->type
= ir
->var
->type
;
241 return visit_continue
;
244 /** Was function linking successful? */
249 * Shader program being linked
251 * This is only used for logging error messages.
253 gl_shader_program
*prog
;
255 /** List of shaders available for linking. */
256 gl_shader
**shader_list
;
258 /** Number of shaders available for linking. */
259 unsigned num_shaders
;
262 * Final linked shader
264 * This is used two ways. It is used to find global variables in the
265 * linked shader that are accessed by the function. It is also used to add
266 * global variables from the shader where the function originated.
271 * Table of variables local to the function.
278 * Searches a list of shaders for a particular function definition
280 ir_function_signature
*
281 find_matching_signature(const char *name
, const exec_list
*actual_parameters
,
282 gl_shader
**shader_list
, unsigned num_shaders
,
285 for (unsigned i
= 0; i
< num_shaders
; i
++) {
286 ir_function
*const f
= shader_list
[i
]->symbols
->get_function(name
);
291 ir_function_signature
*sig
= f
->matching_signature(actual_parameters
);
293 if ((sig
== NULL
) || !sig
->is_defined
)
296 /* If this function expects to bind to a built-in function and the
297 * signature that we found isn't a built-in, keep looking. Also keep
298 * looking if we expect a non-built-in but found a built-in.
300 if (use_builtin
!= sig
->is_builtin())
311 link_function_calls(gl_shader_program
*prog
, gl_shader
*main
,
312 gl_shader
**shader_list
, unsigned num_shaders
)
314 call_link_visitor
v(prog
, main
, shader_list
, num_shaders
);