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 "glsl_symbol_table.h"
25 #include "glsl_parser_extras.h"
29 #include "util/hash_table.h"
31 #include "main/mtypes.h"
33 static ir_function_signature
*
34 find_matching_signature(const char *name
, const exec_list
*actual_parameters
,
35 glsl_symbol_table
*symbols
);
39 class call_link_visitor
: public ir_hierarchical_visitor
{
41 call_link_visitor(gl_shader_program
*prog
, gl_linked_shader
*linked
,
42 gl_shader
**shader_list
, unsigned num_shaders
)
45 this->shader_list
= shader_list
;
46 this->num_shaders
= num_shaders
;
48 this->linked
= linked
;
50 this->locals
= _mesa_pointer_set_create(NULL
);
55 _mesa_set_destroy(this->locals
, NULL
);
58 virtual ir_visitor_status
visit(ir_variable
*ir
)
60 _mesa_set_add(locals
, ir
);
61 return visit_continue
;
64 virtual ir_visitor_status
visit_enter(ir_call
*ir
)
66 /* If ir is an ir_call from a function that was imported from another
67 * shader callee will point to an ir_function_signature in the original
68 * shader. In this case the function signature MUST NOT BE MODIFIED.
69 * Doing so will modify the original shader. This may prevent that
70 * shader from being linkable in other programs.
72 const ir_function_signature
*const callee
= ir
->callee
;
73 assert(callee
!= NULL
);
74 const char *const name
= callee
->function_name();
76 /* We don't actually need to find intrinsics; they're not real */
77 if (callee
->is_intrinsic())
78 return visit_continue
;
80 /* Determine if the requested function signature already exists in the
81 * final linked shader. If it does, use it as the target of the call.
83 ir_function_signature
*sig
=
84 find_matching_signature(name
, &callee
->parameters
, linked
->symbols
);
87 return visit_continue
;
90 /* Try to find the signature in one of the other shaders that is being
91 * linked. If it's not found there, return an error.
93 for (unsigned i
= 0; i
< num_shaders
; i
++) {
94 sig
= find_matching_signature(name
, &ir
->actual_parameters
,
95 shader_list
[i
]->symbols
);
101 /* FINISHME: Log the full signature of unresolved function.
103 linker_error(this->prog
, "unresolved reference to function `%s'\n",
105 this->success
= false;
109 /* Find the prototype information in the linked shader. Generate any
110 * details that may be missing.
112 ir_function
*f
= linked
->symbols
->get_function(name
);
114 f
= new(linked
) ir_function(name
);
116 /* Add the new function to the linked IR. Put it at the end
117 * so that it comes after any global variable declarations
120 linked
->symbols
->add_function(f
);
121 linked
->ir
->push_tail(f
);
124 ir_function_signature
*linked_sig
=
125 f
->exact_matching_signature(NULL
, &callee
->parameters
);
126 if (linked_sig
== NULL
) {
127 linked_sig
= new(linked
) ir_function_signature(callee
->return_type
);
128 f
->add_signature(linked_sig
);
131 /* At this point linked_sig and called may be the same. If ir is an
132 * ir_call from linked then linked_sig and callee will be
133 * ir_function_signatures that have no definitions (is_defined is false).
135 assert(!linked_sig
->is_defined
);
136 assert(linked_sig
->body
.is_empty());
138 /* Create an in-place clone of the function definition. This multistep
139 * process introduces some complexity here, but it has some advantages.
140 * The parameter list and the and function body are cloned separately.
141 * The clone of the parameter list is used to prime the hashtable used
142 * to replace variable references in the cloned body.
144 * The big advantage is that the ir_function_signature does not change.
145 * This means that we don't have to process the rest of the IR tree to
146 * patch ir_call nodes. In addition, there is no way to remove or
147 * replace signature stored in a function. One could easily be added,
148 * but this avoids the need.
150 struct hash_table
*ht
= _mesa_pointer_hash_table_create(NULL
);
152 exec_list formal_parameters
;
153 foreach_in_list(const ir_instruction
, original
, &sig
->parameters
) {
154 assert(const_cast<ir_instruction
*>(original
)->as_variable());
156 ir_instruction
*copy
= original
->clone(linked
, ht
);
157 formal_parameters
.push_tail(copy
);
160 linked_sig
->replace_parameters(&formal_parameters
);
162 linked_sig
->intrinsic_id
= sig
->intrinsic_id
;
164 if (sig
->is_defined
) {
165 foreach_in_list(const ir_instruction
, original
, &sig
->body
) {
166 ir_instruction
*copy
= original
->clone(linked
, ht
);
167 linked_sig
->body
.push_tail(copy
);
170 linked_sig
->is_defined
= true;
173 _mesa_hash_table_destroy(ht
, NULL
);
175 /* Patch references inside the function to things outside the function
176 * (i.e., function calls and global variables).
178 linked_sig
->accept(this);
180 ir
->callee
= linked_sig
;
182 return visit_continue
;
185 virtual ir_visitor_status
visit_leave(ir_call
*ir
)
187 /* Traverse list of function parameters, and for array parameters
188 * propagate max_array_access. Otherwise arrays that are only referenced
189 * from inside functions via function parameters will be incorrectly
190 * optimized. This will lead to incorrect code being generated (or worse).
191 * Do it when leaving the node so the children would propagate their
192 * array accesses first.
195 const exec_node
*formal_param_node
= ir
->callee
->parameters
.get_head();
196 if (formal_param_node
) {
197 const exec_node
*actual_param_node
= ir
->actual_parameters
.get_head();
198 while (!actual_param_node
->is_tail_sentinel()) {
199 ir_variable
*formal_param
= (ir_variable
*) formal_param_node
;
200 ir_rvalue
*actual_param
= (ir_rvalue
*) actual_param_node
;
202 formal_param_node
= formal_param_node
->get_next();
203 actual_param_node
= actual_param_node
->get_next();
205 if (formal_param
->type
->is_array()) {
206 ir_dereference_variable
*deref
= actual_param
->as_dereference_variable();
207 if (deref
&& deref
->var
&& deref
->var
->type
->is_array()) {
208 deref
->var
->data
.max_array_access
=
209 MAX2(formal_param
->data
.max_array_access
,
210 deref
->var
->data
.max_array_access
);
215 return visit_continue
;
218 virtual ir_visitor_status
visit(ir_dereference_variable
*ir
)
220 if (_mesa_set_search(locals
, ir
->var
) == NULL
) {
221 /* The non-function variable must be a global, so try to find the
222 * variable in the shader's symbol table. If the variable is not
223 * found, then it's a global that *MUST* be defined in the original
226 ir_variable
*var
= linked
->symbols
->get_variable(ir
->var
->name
);
228 /* Clone the ir_variable that the dereference already has and add
229 * it to the linked shader.
231 var
= ir
->var
->clone(linked
, NULL
);
232 linked
->symbols
->add_variable(var
);
233 linked
->ir
->push_head(var
);
235 if (var
->type
->is_array()) {
236 /* It is possible to have a global array declared in multiple
237 * shaders without a size. The array is implicitly sized by
238 * the maximal access to it in *any* shader. Because of this,
239 * we need to track the maximal access to the array as linking
240 * pulls more functions in that access the array.
242 var
->data
.max_array_access
=
243 MAX2(var
->data
.max_array_access
,
244 ir
->var
->data
.max_array_access
);
246 if (var
->type
->length
== 0 && ir
->var
->type
->length
!= 0)
247 var
->type
= ir
->var
->type
;
249 if (var
->is_interface_instance()) {
250 /* Similarly, we need implicit sizes of arrays within interface
251 * blocks to be sized by the maximal access in *any* shader.
253 int *const linked_max_ifc_array_access
=
254 var
->get_max_ifc_array_access();
255 int *const ir_max_ifc_array_access
=
256 ir
->var
->get_max_ifc_array_access();
258 assert(linked_max_ifc_array_access
!= NULL
);
259 assert(ir_max_ifc_array_access
!= NULL
);
261 for (unsigned i
= 0; i
< var
->get_interface_type()->length
;
263 linked_max_ifc_array_access
[i
] =
264 MAX2(linked_max_ifc_array_access
[i
],
265 ir_max_ifc_array_access
[i
]);
273 return visit_continue
;
276 /** Was function linking successful? */
281 * Shader program being linked
283 * This is only used for logging error messages.
285 gl_shader_program
*prog
;
287 /** List of shaders available for linking. */
288 gl_shader
**shader_list
;
290 /** Number of shaders available for linking. */
291 unsigned num_shaders
;
294 * Final linked shader
296 * This is used two ways. It is used to find global variables in the
297 * linked shader that are accessed by the function. It is also used to add
298 * global variables from the shader where the function originated.
300 gl_linked_shader
*linked
;
303 * Table of variables local to the function.
308 } /* anonymous namespace */
311 * Searches a list of shaders for a particular function definition
313 ir_function_signature
*
314 find_matching_signature(const char *name
, const exec_list
*actual_parameters
,
315 glsl_symbol_table
*symbols
)
317 ir_function
*const f
= symbols
->get_function(name
);
320 ir_function_signature
*sig
=
321 f
->matching_signature(NULL
, actual_parameters
, false);
323 if (sig
&& (sig
->is_defined
|| sig
->is_intrinsic()))
332 link_function_calls(gl_shader_program
*prog
, gl_linked_shader
*main
,
333 gl_shader
**shader_list
, unsigned num_shaders
)
335 call_link_visitor
v(prog
, main
, shader_list
, num_shaders
);