summaryrefslogtreecommitdiff
path: root/ast_function.cpp
blob: 300108cb73e46202203d9dca24b0a2d4a296430b (plain)
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
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
/*
 * 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.
 */

#include <cstdio>
#include "glsl_symbol_table.h"
#include "ast.h"
#include "glsl_types.h"
#include "ir.h"

static unsigned
process_parameters(exec_list *instructions, exec_list *actual_parameters,
		   exec_list *parameters,
		   struct _mesa_glsl_parse_state *state)
{
   unsigned count = 0;

   foreach_list (n, parameters) {
      ast_node *const ast = exec_node_data(ast_node, n, link);
      ir_rvalue *const result = ast->hir(instructions, state);

      actual_parameters->push_tail(result);
      count++;
   }

   return count;
}


static ir_rvalue *
process_call(exec_list *instructions, ir_function *f,
	     YYLTYPE *loc, exec_list *actual_parameters,
	     struct _mesa_glsl_parse_state *state)
{
   const ir_function_signature *sig =
      f->matching_signature(actual_parameters);

   /* The instructions param will be used when the FINISHMEs below are done */
   (void) instructions;

   if (sig != NULL) {
      /* Verify that 'out' and 'inout' actual parameters are lvalues.  This
       * isn't done in ir_function::matching_signature because that function
       * cannot generate the necessary diagnostics.
       */
      exec_list_iterator actual_iter = actual_parameters->iterator();
      exec_list_iterator formal_iter = sig->parameters.iterator();

      while (actual_iter.has_next()) {
	 ir_rvalue *actual = (ir_rvalue *) actual_iter.get();
	 ir_variable *formal = (ir_variable *) formal_iter.get();

	 assert(actual != NULL);
	 assert(formal != NULL);

	 if ((formal->mode == ir_var_out)
	     || (formal->mode == ir_var_inout)) {
	    if (! actual->is_lvalue()) {
	       /* FINISHME: Log a better diagnostic here.  There is no way
		* FINISHME: to tell the user which parameter is invalid.
		*/
	       _mesa_glsl_error(loc, state, "`%s' parameter is not lvalue",
				(formal->mode == ir_var_out) ? "out" : "inout");
	    }
	 }

	 actual_iter.next();
	 formal_iter.next();
      }

      /* FINISHME: The list of actual parameters needs to be modified to
       * FINISHME: include any necessary conversions.
       */
      return new ir_call(sig, actual_parameters);
   } else {
      /* FINISHME: Log a better error message here.  G++ will show the types
       * FINISHME: of the actual parameters and the set of candidate
       * FINISHME: functions.  A different error should also be logged when
       * FINISHME: multiple functions match.
       */
      _mesa_glsl_error(loc, state, "no matching function for call to `%s'",
		       f->name);
      return ir_call::get_error_instruction();
   }
}


static ir_rvalue *
match_function_by_name(exec_list *instructions, const char *name,
		       YYLTYPE *loc, exec_list *parameters,
		       struct _mesa_glsl_parse_state *state)
{
   ir_function *f = state->symbols->get_function(name);

   if (f == NULL) {
      _mesa_glsl_error(loc, state, "function `%s' undeclared", name);
      return ir_call::get_error_instruction();
   }

   /* Once we've determined that the function being called might exist,
    * process the parameters.
    */
   exec_list actual_parameters;
   process_parameters(instructions, &actual_parameters, parameters, state);

   /* After processing the function's actual parameters, try to find an
    * overload of the function that matches.
    */
   return process_call(instructions, f, loc, &actual_parameters, state);
}


/**
 * Perform automatic type conversion of constructor parameters
 */
static ir_rvalue *
convert_component(ir_rvalue *src, const glsl_type *desired_type)
{
   const unsigned a = desired_type->base_type;
   const unsigned b = src->type->base_type;

   if (src->type->is_error())
      return src;

   assert(a <= GLSL_TYPE_BOOL);
   assert(b <= GLSL_TYPE_BOOL);

   if ((a == b) || (src->type->is_integer() && desired_type->is_integer()))
      return src;

   switch (a) {
   case GLSL_TYPE_UINT:
   case GLSL_TYPE_INT:
      if (b == GLSL_TYPE_FLOAT)
	 return new ir_expression(ir_unop_f2i, desired_type, src, NULL);
      else {
	 assert(b == GLSL_TYPE_BOOL);
	 return new ir_expression(ir_unop_f2b, desired_type, src, NULL);
      }
   case GLSL_TYPE_FLOAT:
      switch (b) {
      case GLSL_TYPE_UINT:
	 return new ir_expression(ir_unop_u2f, desired_type, src, NULL);
      case GLSL_TYPE_INT:
	 return new ir_expression(ir_unop_i2f, desired_type, src, NULL);
      case GLSL_TYPE_BOOL:
	 return new ir_expression(ir_unop_b2f, desired_type, src, NULL);
      }
      break;
   case GLSL_TYPE_BOOL: {
      int z = 0;
      ir_constant *const zero = new ir_constant(src->type, &z);

      return new ir_expression(ir_binop_nequal, desired_type, src, zero);
   }
   }

   assert(!"Should not get here.");
   return NULL;
}


/**
 * Dereference a specific component from a scalar, vector, or matrix
 */
static ir_rvalue *
dereference_component(ir_rvalue *src, unsigned component)
{
   assert(component < src->type->components());

   if (src->type->is_scalar()) {
      return src;
   } else if (src->type->is_vector()) {
      return new ir_swizzle(src, component, 0, 0, 0, 1);
   } else {
      assert(src->type->is_matrix());

      /* Dereference a row of the matrix, then call this function again to get
       * a specific element from that row.
       */
      const int c = component / src->type->column_type()->vector_elements;
      const int r = component % src->type->column_type()->vector_elements;
      ir_constant *const col_index = new ir_constant(glsl_type::int_type, &c);
      ir_dereference *const col = new ir_dereference_array(src, col_index);

      col->type = src->type->column_type();

      return dereference_component(col, r);
   }

   assert(!"Should not get here.");
   return NULL;
}


static ir_rvalue *
process_array_constructor(exec_list *instructions,
			  const glsl_type *constructor_type,
			  YYLTYPE *loc, exec_list *parameters,
			  struct _mesa_glsl_parse_state *state)
{
   /* Array constructors come in two forms: sized and unsized.  Sized array
    * constructors look like 'vec4[2](a, b)', where 'a' and 'b' are vec4
    * variables.  In this case the number of parameters must exactly match the
    * specified size of the array.
    *
    * Unsized array constructors look like 'vec4[](a, b)', where 'a' and 'b'
    * are vec4 variables.  In this case the size of the array being constructed
    * is determined by the number of parameters.
    *
    * From page 52 (page 58 of the PDF) of the GLSL 1.50 spec:
    *
    *    "There must be exactly the same number of arguments as the size of
    *    the array being constructed. If no size is present in the
    *    constructor, then the array is explicitly sized to the number of
    *    arguments provided. The arguments are assigned in order, starting at
    *    element 0, to the elements of the constructed array. Each argument
    *    must be the same type as the element type of the array, or be a type
    *    that can be converted to the element type of the array according to
    *    Section 4.1.10 "Implicit Conversions.""
    */
   exec_list actual_parameters;
   const unsigned parameter_count =
      process_parameters(instructions, &actual_parameters, parameters, state);

   if ((parameter_count == 0)
       || ((constructor_type->length != 0)
	   && (constructor_type->length != parameter_count))) {
      const unsigned min_param = (constructor_type->length == 0)
	 ? 1 : constructor_type->length;

      _mesa_glsl_error(loc, state, "array constructor must have %s %u "
		       "parameter%s",
		       (constructor_type->length != 0) ? "at least" : "exactly",
		       min_param, (min_param <= 1) ? "" : "s");
      return ir_call::get_error_instruction();
   }

   if (constructor_type->length == 0) {
      constructor_type =
	 glsl_type::get_array_instance(constructor_type->element_type(),
				       parameter_count);
      assert(constructor_type != NULL);
      assert(constructor_type->length == parameter_count);
   }

   ir_function *f = state->symbols->get_function(constructor_type->name);

   /* If the constructor for this type of array does not exist, generate the
    * prototype and add it to the symbol table.
    */
   if (f == NULL) {
      f = constructor_type->generate_constructor(state->symbols);
   }

   ir_rvalue *const r =
      process_call(instructions, f, loc, &actual_parameters, state);

   assert(r != NULL);
   assert(r->type->is_error() || (r->type == constructor_type));

   return r;
}


ir_rvalue *
ast_function_expression::hir(exec_list *instructions,
			     struct _mesa_glsl_parse_state *state)
{
   /* There are three sorts of function calls.
    *
    * 1. contstructors - The first subexpression is an ast_type_specifier.
    * 2. methods - Only the .length() method of array types.
    * 3. functions - Calls to regular old functions.
    *
    * Method calls are actually detected when the ast_field_selection
    * expression is handled.
    */
   if (is_constructor()) {
      const ast_type_specifier *type = (ast_type_specifier *) subexpressions[0];
      YYLTYPE loc = type->get_location();
      const char *name;

      const glsl_type *const constructor_type = type->glsl_type(& name, state);


      /* Constructors for samplers are illegal.
       */
      if (constructor_type->is_sampler()) {
	 _mesa_glsl_error(& loc, state, "cannot construct sampler type `%s'",
			  constructor_type->name);
	 return ir_call::get_error_instruction();
      }

      if (constructor_type->is_array()) {
	 if (state->language_version <= 110) {
	    _mesa_glsl_error(& loc, state,
			     "array constructors forbidden in GLSL 1.10");
	    return ir_call::get_error_instruction();
	 }

	 return process_array_constructor(instructions, constructor_type,
					  & loc, &this->expressions, state);
      }

      /* There are two kinds of constructor call.  Constructors for built-in
       * language types, such as mat4 and vec2, are free form.  The only
       * requirement is that the parameters must provide enough values of the
       * correct scalar type.  Constructors for arrays and structures must
       * have the exact number of parameters with matching types in the
       * correct order.  These constructors follow essentially the same type
       * matching rules as functions.
       */
      if (constructor_type->is_numeric() || constructor_type->is_boolean()) {
	 /* Constructing a numeric type has a couple steps.  First all values
	  * passed to the constructor are broken into individual parameters
	  * and type converted to the base type of the thing being constructed.
	  *
	  * At that point we have some number of values that match the base
	  * type of the thing being constructed.  Now the constructor can be
	  * treated like a function call.  Each numeric type has a small set
	  * of constructor functions.  The set of new parameters will either
	  * match one of those functions or the original constructor is
	  * invalid.
	  */
	 const glsl_type *const base_type = constructor_type->get_base_type();

	 /* Total number of components of the type being constructed.
	  */
	 const unsigned type_components = constructor_type->components();

	 /* Number of components from parameters that have actually been
	  * consumed.  This is used to perform several kinds of error checking.
	  */
	 unsigned components_used = 0;

	 unsigned matrix_parameters = 0;
	 unsigned nonmatrix_parameters = 0;
	 exec_list actual_parameters;

	 assert(!this->expressions.is_empty());

	 foreach_list (n, &this->expressions) {
	    ast_node *ast = exec_node_data(ast_node, n, link);
	    ir_rvalue *const result =
	       ast->hir(instructions, state)->as_rvalue();

	    /* From page 50 (page 56 of the PDF) of the GLSL 1.50 spec:
	     *
	     *    "It is an error to provide extra arguments beyond this
	     *    last used argument."
	     */
	    if (components_used >= type_components) {
	       _mesa_glsl_error(& loc, state, "too many parameters to `%s' "
				"constructor",
				constructor_type->name);
	       return ir_call::get_error_instruction();
	    }

	    if (!result->type->is_numeric() && !result->type->is_boolean()) {
	       _mesa_glsl_error(& loc, state, "cannot construct `%s' from a "
				"non-numeric data type",
				constructor_type->name);
	       return ir_call::get_error_instruction();
	    }

	    /* Count the number of matrix and nonmatrix parameters.  This
	     * is used below to enforce some of the constructor rules.
	     */
	    if (result->type->is_matrix())
	       matrix_parameters++;
	    else
	       nonmatrix_parameters++;


	    /* Process each of the components of the parameter.  Dereference
	     * each component individually, perform any type conversions, and
	     * add it to the parameter list for the constructor.
	     */
	    for (unsigned i = 0; i < result->type->components(); i++) {
	       if (components_used >= type_components)
		  break;

	       ir_rvalue *const component =
		  convert_component(dereference_component(result, i),
				    base_type);

	       /* All cases that could result in component->type being the
		* error type should have already been caught above.
		*/
	       assert(component->type == base_type);

	       /* Don't actually generate constructor calls for scalars.
		* Instead, do the usual component selection and conversion,
		* and return the single component.
		*/
	       if (constructor_type->is_scalar())
		  return component;

	       actual_parameters.push_tail(component);
	       components_used++;
	    }
	 }

	 /* From page 28 (page 34 of the PDF) of the GLSL 1.10 spec:
	  *
	  *    "It is an error to construct matrices from other matrices. This
	  *    is reserved for future use."
	  */
	 if ((state->language_version <= 110) && (matrix_parameters > 0)
	     && constructor_type->is_matrix()) {
	    _mesa_glsl_error(& loc, state, "cannot construct `%s' from a "
			     "matrix in GLSL 1.10",
			     constructor_type->name);
	    return ir_call::get_error_instruction();
	 }

	 /* From page 50 (page 56 of the PDF) of the GLSL 1.50 spec:
	  *
	  *    "If a matrix argument is given to a matrix constructor, it is
	  *    an error to have any other arguments."
	  */
	 if ((matrix_parameters > 0)
	     && ((matrix_parameters + nonmatrix_parameters) > 1)
	     && constructor_type->is_matrix()) {
	    _mesa_glsl_error(& loc, state, "for matrix `%s' constructor, "
			     "matrix must be only parameter",
			     constructor_type->name);
	    return ir_call::get_error_instruction();
	 }

	 /* From page 28 (page 34 of the PDF) of the GLSL 1.10 spec:
	  *
	  *    "In these cases, there must be enough components provided in the
	  *    arguments to provide an initializer for every component in the
	  *    constructed value."
	  */
	 if ((components_used < type_components) && (components_used != 1)) {
	    _mesa_glsl_error(& loc, state, "too few components to construct "
			     "`%s'",
			     constructor_type->name);
	    return ir_call::get_error_instruction();
	 }

	 ir_function *f = state->symbols->get_function(constructor_type->name);
	 if (f == NULL) {
	    _mesa_glsl_error(& loc, state, "no constructor for type `%s'",
			     constructor_type->name);
	    return ir_call::get_error_instruction();
	 }

	 const ir_function_signature *sig =
	    f->matching_signature(& actual_parameters);
	 if (sig != NULL) {
	    return new ir_call(sig, & actual_parameters);
	 } else {
	    /* FINISHME: Log a better error message here.  G++ will show the
	     * FINSIHME: types of the actual parameters and the set of
	     * FINSIHME: candidate functions.  A different error should also be
	     * FINSIHME: logged when multiple functions match.
	     */
	    _mesa_glsl_error(& loc, state, "no matching constructor for `%s'",
			     constructor_type->name);
	    return ir_call::get_error_instruction();
	 }
      }

      return ir_call::get_error_instruction();
   } else {
      const ast_expression *id = subexpressions[0];
      YYLTYPE loc = id->get_location();

      return match_function_by_name(instructions, 
				    id->primary_expression.identifier, & loc,
				    &this->expressions, state);
   }

   return ir_call::get_error_instruction();
}