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
,
39 class call_link_visitor
: public ir_hierarchical_visitor
{
41 call_link_visitor(gl_shader_program
*prog
, gl_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
= hash_table_ctor(0, hash_table_pointer_hash
,
51 hash_table_pointer_compare
);
56 hash_table_dtor(this->locals
);
59 virtual ir_visitor_status
visit(ir_variable
*ir
)
61 hash_table_insert(locals
, ir
, ir
);
62 return visit_continue
;
65 virtual ir_visitor_status
visit_enter(ir_call
*ir
)
67 /* If ir is an ir_call from a function that was imported from another
68 * shader callee will point to an ir_function_signature in the original
69 * shader. In this case the function signature MUST NOT BE MODIFIED.
70 * Doing so will modify the original shader. This may prevent that
71 * shader from being linkable in other programs.
73 const ir_function_signature
*const callee
= ir
->callee
;
74 assert(callee
!= NULL
);
75 const char *const name
= callee
->function_name();
77 /* Determine if the requested function signature already exists in the
78 * final linked shader. If it does, use it as the target of the call.
80 ir_function_signature
*sig
=
81 find_matching_signature(name
, &callee
->parameters
, &linked
, 1,
85 return visit_continue
;
88 /* Try to find the signature in one of the other shaders that is being
89 * linked. If it's not found there, return an error.
91 sig
= find_matching_signature(name
, &ir
->actual_parameters
, shader_list
,
92 num_shaders
, ir
->use_builtin
);
94 /* FINISHME: Log the full signature of unresolved function.
96 linker_error(this->prog
, "unresolved reference to function `%s'\n",
98 this->success
= false;
102 /* Find the prototype information in the linked shader. Generate any
103 * details that may be missing.
105 ir_function
*f
= linked
->symbols
->get_function(name
);
107 f
= new(linked
) ir_function(name
);
109 /* Add the new function to the linked IR. Put it at the end
110 * so that it comes after any global variable declarations
113 linked
->symbols
->add_function(f
);
114 linked
->ir
->push_tail(f
);
117 ir_function_signature
*linked_sig
=
118 f
->exact_matching_signature(NULL
, &callee
->parameters
);
119 if ((linked_sig
== NULL
)
120 || ((linked_sig
!= NULL
)
121 && (linked_sig
->is_builtin() != ir
->use_builtin
))) {
122 linked_sig
= new(linked
) ir_function_signature(callee
->return_type
);
123 f
->add_signature(linked_sig
);
126 /* At this point linked_sig and called may be the same. If ir is an
127 * ir_call from linked then linked_sig and callee will be
128 * ir_function_signatures that have no definitions (is_defined is false).
130 assert(!linked_sig
->is_defined
);
131 assert(linked_sig
->body
.is_empty());
133 /* Create an in-place clone of the function definition. This multistep
134 * process introduces some complexity here, but it has some advantages.
135 * The parameter list and the and function body are cloned separately.
136 * The clone of the parameter list is used to prime the hashtable used
137 * to replace variable references in the cloned body.
139 * The big advantage is that the ir_function_signature does not change.
140 * This means that we don't have to process the rest of the IR tree to
141 * patch ir_call nodes. In addition, there is no way to remove or
142 * replace signature stored in a function. One could easily be added,
143 * but this avoids the need.
145 struct hash_table
*ht
= hash_table_ctor(0, hash_table_pointer_hash
,
146 hash_table_pointer_compare
);
147 exec_list formal_parameters
;
148 foreach_list_const(node
, &sig
->parameters
) {
149 const ir_instruction
*const original
= (ir_instruction
*) node
;
150 assert(const_cast<ir_instruction
*>(original
)->as_variable());
152 ir_instruction
*copy
= original
->clone(linked
, ht
);
153 formal_parameters
.push_tail(copy
);
156 linked_sig
->replace_parameters(&formal_parameters
);
158 if (sig
->is_defined
) {
159 foreach_list_const(node
, &sig
->body
) {
160 const ir_instruction
*const original
= (ir_instruction
*) node
;
162 ir_instruction
*copy
= original
->clone(linked
, ht
);
163 linked_sig
->body
.push_tail(copy
);
166 linked_sig
->is_defined
= true;
171 /* Patch references inside the function to things outside the function
172 * (i.e., function calls and global variables).
174 linked_sig
->accept(this);
176 ir
->callee
= linked_sig
;
178 return visit_continue
;
181 virtual ir_visitor_status
visit_leave(ir_call
*ir
)
183 /* Traverse list of function parameters, and for array parameters
184 * propagate max_array_access. Otherwise arrays that are only referenced
185 * from inside functions via function parameters will be incorrectly
186 * optimized. This will lead to incorrect code being generated (or worse).
187 * Do it when leaving the node so the children would propagate their
188 * array accesses first.
191 const exec_node
*formal_param_node
= ir
->callee
->parameters
.get_head();
192 if (formal_param_node
) {
193 const exec_node
*actual_param_node
= ir
->actual_parameters
.get_head();
194 while (!actual_param_node
->is_tail_sentinel()) {
195 ir_variable
*formal_param
= (ir_variable
*) formal_param_node
;
196 ir_rvalue
*actual_param
= (ir_rvalue
*) actual_param_node
;
198 formal_param_node
= formal_param_node
->get_next();
199 actual_param_node
= actual_param_node
->get_next();
201 if (formal_param
->type
->is_array()) {
202 ir_dereference_variable
*deref
= actual_param
->as_dereference_variable();
203 if (deref
&& deref
->var
&& deref
->var
->type
->is_array()) {
204 deref
->var
->data
.max_array_access
=
205 MAX2(formal_param
->data
.max_array_access
,
206 deref
->var
->data
.max_array_access
);
211 return visit_continue
;
214 virtual ir_visitor_status
visit(ir_dereference_variable
*ir
)
216 if (hash_table_find(locals
, ir
->var
) == NULL
) {
217 /* The non-function variable must be a global, so try to find the
218 * variable in the shader's symbol table. If the variable is not
219 * found, then it's a global that *MUST* be defined in the original
222 ir_variable
*var
= linked
->symbols
->get_variable(ir
->var
->name
);
224 /* Clone the ir_variable that the dereference already has and add
225 * it to the linked shader.
227 var
= ir
->var
->clone(linked
, NULL
);
228 linked
->symbols
->add_variable(var
);
229 linked
->ir
->push_head(var
);
231 if (var
->type
->is_array()) {
232 /* It is possible to have a global array declared in multiple
233 * shaders without a size. The array is implicitly sized by
234 * the maximal access to it in *any* shader. Because of this,
235 * we need to track the maximal access to the array as linking
236 * pulls more functions in that access the array.
238 var
->data
.max_array_access
=
239 MAX2(var
->data
.max_array_access
,
240 ir
->var
->data
.max_array_access
);
242 if (var
->type
->length
== 0 && ir
->var
->type
->length
!= 0)
243 var
->type
= ir
->var
->type
;
245 if (var
->is_interface_instance()) {
246 /* Similarly, we need implicit sizes of arrays within interface
247 * blocks to be sized by the maximal access in *any* shader.
249 for (unsigned i
= 0; i
< var
->get_interface_type()->length
;
251 var
->max_ifc_array_access
[i
] =
252 MAX2(var
->max_ifc_array_access
[i
],
253 ir
->var
->max_ifc_array_access
[i
]);
261 return visit_continue
;
264 /** Was function linking successful? */
269 * Shader program being linked
271 * This is only used for logging error messages.
273 gl_shader_program
*prog
;
275 /** List of shaders available for linking. */
276 gl_shader
**shader_list
;
278 /** Number of shaders available for linking. */
279 unsigned num_shaders
;
282 * Final linked shader
284 * This is used two ways. It is used to find global variables in the
285 * linked shader that are accessed by the function. It is also used to add
286 * global variables from the shader where the function originated.
291 * Table of variables local to the function.
296 } /* anonymous namespace */
299 * Searches a list of shaders for a particular function definition
301 ir_function_signature
*
302 find_matching_signature(const char *name
, const exec_list
*actual_parameters
,
303 gl_shader
**shader_list
, unsigned num_shaders
,
306 for (unsigned i
= 0; i
< num_shaders
; i
++) {
307 ir_function
*const f
= shader_list
[i
]->symbols
->get_function(name
);
312 ir_function_signature
*sig
=
313 f
->matching_signature(NULL
, actual_parameters
);
316 (!sig
->is_defined
&& !sig
->is_intrinsic
))
319 /* If this function expects to bind to a built-in function and the
320 * signature that we found isn't a built-in, keep looking. Also keep
321 * looking if we expect a non-built-in but found a built-in.
323 if (use_builtin
!= sig
->is_builtin())
334 link_function_calls(gl_shader_program
*prog
, gl_shader
*main
,
335 gl_shader
**shader_list
, unsigned num_shaders
)
337 call_link_visitor
v(prog
, main
, shader_list
, num_shaders
);