summaryrefslogtreecommitdiff
path: root/ir.h
blob: 9277f762042a96e4cddde348e0114994e321fd81 (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
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
/* -*- c++ -*- */
/*
 * 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.
 */

#pragma once
#ifndef IR_H
#define IR_H

#include <cstdio>
#include <cstdlib>

#include "list.h"
#include "ir_visitor.h"
#include "ir_hierarchical_visitor.h"

struct ir_program {
   void *bong_hits;
};

/**
 * Base class of all IR instructions
 */
class ir_instruction : public exec_node {
public:
   const struct glsl_type *type;

   class ir_constant *constant_expression_value();

   /** ir_print_visitor helper for debugging. */
   void print(void) const;

   virtual void accept(ir_visitor *) = 0;
   virtual ir_visitor_status accept(ir_hierarchical_visitor *) = 0;
   virtual ir_instruction *clone(struct hash_table *ht) const = 0;

   /**
    * \name IR instruction downcast functions
    *
    * These functions either cast the object to a derived class or return
    * \c NULL if the object's type does not match the specified derived class.
    * Additional downcast functions will be added as needed.
    */
   /*@{*/
   virtual class ir_variable *          as_variable()         { return NULL; }
   virtual class ir_function *          as_function()         { return NULL; }
   virtual class ir_dereference *       as_dereference()      { return NULL; }
   virtual class ir_dereference_array *	as_dereference_array() { return NULL; }
   virtual class ir_rvalue *            as_rvalue()           { return NULL; }
   virtual class ir_loop *              as_loop()             { return NULL; }
   virtual class ir_assignment *        as_assignment()       { return NULL; }
   virtual class ir_call *              as_call()             { return NULL; }
   virtual class ir_return *            as_return()           { return NULL; }
   virtual class ir_if *                as_if()               { return NULL; }
   virtual class ir_swizzle *           as_swizzle()          { return NULL; }
   virtual class ir_constant *          as_constant()         { return NULL; }
   /*@}*/

protected:
   ir_instruction()
   {
      /* empty */
   }
};


class ir_rvalue : public ir_instruction {
public:
   virtual ir_rvalue * as_rvalue()
   {
      return this;
   }

   virtual bool is_lvalue()
   {
      return false;
   }

   /**
    * Get the variable that is ultimately referenced by an r-value
    */
   virtual ir_variable *variable_referenced()
   {
      return NULL;
   }


   /**
    * If an r-value is a reference to a whole variable, get that variable
    *
    * \return
    * Pointer to a variable that is completely dereferenced by the r-value.  If
    * the r-value is not a dereference or the dereference does not access the
    * entire variable (i.e., it's just one array element, struct field), \c NULL
    * is returned.
    */
   virtual ir_variable *whole_variable_referenced()
   {
      return NULL;
   }

protected:
   ir_rvalue()
   {
      /* empty */
   }
};


enum ir_variable_mode {
   ir_var_auto = 0,
   ir_var_uniform,
   ir_var_in,
   ir_var_out,
   ir_var_inout
};

enum ir_variable_interpolation {
   ir_var_smooth = 0,
   ir_var_flat,
   ir_var_noperspective
};


class ir_variable : public ir_instruction {
public:
   ir_variable(const struct glsl_type *, const char *);

   virtual ir_instruction *clone(struct hash_table *ht) const;

   virtual ir_variable *as_variable()
   {
      return this;
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);


   /**
    * Get the string value for the interpolation qualifier
    *
    * \return
    * If none of \c shader_in or \c shader_out is set, an empty string will
    * be returned.  Otherwise the string that would be used in a shader to
    * specify \c mode will be returned.
    */
   const char *interpolation_string() const;

   /**
    * Calculate the number of slots required to hold this variable
    *
    * This is used to determine how many uniform or varying locations a variable
    * occupies.  The count is in units of floating point components.
    */
   unsigned component_slots() const;

   const char *name;

   /**
    * Highest element accessed with a constant expression array index
    *
    * Not used for non-array variables.
    */
   unsigned max_array_access;

   unsigned read_only:1;
   unsigned centroid:1;
   unsigned invariant:1;
   /** If the variable is initialized outside of the scope of the shader */
   unsigned shader_in:1;
   /**
    * If the variable value is later used outside of the scope of the shader.
    */
   unsigned shader_out:1;

   unsigned mode:3;
   unsigned interpolation:2;

   /**
    * Flag that the whole array is assignable
    *
    * In GLSL 1.20 and later whole arrays are assignable (and comparable for
    * equality).  This flag enables this behavior.
    */
   unsigned array_lvalue:1;

   /**
    * Storage location of the base of this variable
    *
    * The precise meaning of this field depends on the nature of the variable.
    *
    *   - Vertex shader input: one of the values from \c gl_vert_attrib.
    *   - Vertex shader output: one of the values from \c gl_vert_result.
    *   - Fragment shader input: one of the values from \c gl_frag_attrib.
    *   - Fragment shader output: one of the values from \c gl_frag_result.
    *   - Uniforms: Per-stage uniform slot number.
    *   - Other: This field is not currently used.
    *
    * If the variable is a uniform, shader input, or shader output, and the
    * slot has not been assigned, the value will be -1.
    */
   int location;

   /**
    * Emit a warning if this variable is accessed.
    */
   const char *warn_extension;

   /**
    * Value assigned in the initializer of a variable declared "const"
    */
   ir_constant *constant_value;
};


/*@{*/
/**
 * The representation of a function instance; may be the full definition or
 * simply a prototype.
 */
class ir_function_signature : public ir_instruction {
   /* An ir_function_signature will be part of the list of signatures in
    * an ir_function.
    */
public:
   ir_function_signature(const glsl_type *return_type);

   virtual ir_instruction *clone(struct hash_table *ht) const;

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   /**
    * Get the name of the function for which this is a signature
    */
   const char *function_name() const;

   /**
    * Check whether the qualifiers match between this signature's parameters
    * and the supplied parameter list.  If not, returns the name of the first
    * parameter with mismatched qualifiers (for use in error messages).
    */
   const char *qualifiers_match(exec_list *params);

   /**
    * Replace the current parameter list with the given one.  This is useful
    * if the current information came from a prototype, and either has invalid
    * or missing parameter names.
    */
   void replace_parameters(exec_list *new_params);

   /**
    * Function return type.
    *
    * \note This discards the optional precision qualifier.
    */
   const struct glsl_type *return_type;

   /**
    * List of ir_variable of function parameters.
    *
    * This represents the storage.  The paramaters passed in a particular
    * call will be in ir_call::actual_paramaters.
    */
   struct exec_list parameters;

   /** Whether or not this function has a body (which may be empty). */
   unsigned is_defined:1;

   /** Body of instructions in the function. */
   struct exec_list body;

private:
   /** Function of which this signature is one overload. */
   class ir_function *function;

   friend class ir_function;
};


/**
 * Header for tracking multiple overloaded functions with the same name.
 * Contains a list of ir_function_signatures representing each of the
 * actual functions.
 */
class ir_function : public ir_instruction {
public:
   ir_function(const char *name);

   virtual ir_instruction *clone(struct hash_table *ht) const;

   virtual ir_function *as_function()
   {
      return this;
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   void add_signature(ir_function_signature *sig)
   {
      sig->function = this;
      signatures.push_tail(sig);
   }

   /**
    * Get an iterator for the set of function signatures
    */
   exec_list_iterator iterator()
   {
      return signatures.iterator();
   }

   /**
    * Find a signature that matches a set of actual parameters, taking implicit
    * conversions into account.
    */
   const ir_function_signature *matching_signature(exec_list *actual_param);

   /**
    * Find a signature that exactly matches a set of actual parameters without
    * any implicit type conversions.
    */
   ir_function_signature *exact_matching_signature(exec_list *actual_ps);

   /**
    * Name of the function.
    */
   const char *name;

private:
   /**
    * List of ir_function_signature for each overloaded function with this name.
    */
   struct exec_list signatures;
};

inline const char *ir_function_signature::function_name() const
{
   return function->name;
}
/*@}*/


/**
 * IR instruction representing high-level if-statements
 */
class ir_if : public ir_instruction {
public:
   ir_if(ir_rvalue *condition)
      : condition(condition)
   {
      /* empty */
   }

   virtual ir_instruction *clone(struct hash_table *ht) const;

   virtual ir_if *as_if()
   {
      return this;
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   ir_rvalue *condition;
   /** List of ir_instruction for the body of the then branch */
   exec_list  then_instructions;
   /** List of ir_instruction for the body of the else branch */
   exec_list  else_instructions;
};


/**
 * IR instruction representing a high-level loop structure.
 */
class ir_loop : public ir_instruction {
public:
   ir_loop() : from(NULL), to(NULL), increment(NULL), counter(NULL)
   {
      /* empty */
   }

   virtual ir_instruction *clone(struct hash_table *ht) const;

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   virtual ir_loop *as_loop()
   {
      return this;
   }

   /**
    * Get an iterator for the instructions of the loop body
    */
   exec_list_iterator iterator()
   {
      return body_instructions.iterator();
   }

   /** List of ir_instruction that make up the body of the loop. */
   exec_list body_instructions;

   /**
    * \name Loop counter and controls
    */
   /*@{*/
   ir_rvalue *from;
   ir_rvalue *to;
   ir_rvalue *increment;
   ir_variable *counter;
   /*@}*/
};


class ir_assignment : public ir_rvalue {
public:
   ir_assignment(ir_rvalue *lhs, ir_rvalue *rhs, ir_rvalue *condition);

   virtual ir_instruction *clone(struct hash_table *ht) const;

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   virtual ir_assignment * as_assignment()
   {
      return this;
   }

   /**
    * Left-hand side of the assignment.
    */
   ir_rvalue *lhs;

   /**
    * Value being assigned
    */
   ir_rvalue *rhs;

   /**
    * Optional condition for the assignment.
    */
   ir_rvalue *condition;
};

/* Update ir_expression::num_operands() and operator_strs when
 * updating this list.
 */
enum ir_expression_operation {
   ir_unop_bit_not,
   ir_unop_logic_not,
   ir_unop_neg,
   ir_unop_abs,
   ir_unop_sign,
   ir_unop_rcp,
   ir_unop_rsq,
   ir_unop_sqrt,
   ir_unop_exp,
   ir_unop_log,
   ir_unop_exp2,
   ir_unop_log2,
   ir_unop_f2i,      /**< Float-to-integer conversion. */
   ir_unop_i2f,      /**< Integer-to-float conversion. */
   ir_unop_f2b,      /**< Float-to-boolean conversion */
   ir_unop_b2f,      /**< Boolean-to-float conversion */
   ir_unop_i2b,      /**< int-to-boolean conversion */
   ir_unop_b2i,      /**< Boolean-to-int conversion */
   ir_unop_u2f,      /**< Unsigned-to-float conversion. */

   /**
    * \name Unary floating-point rounding operations.
    */
   /*@{*/
   ir_unop_trunc,
   ir_unop_ceil,
   ir_unop_floor,
   /*@}*/

   /**
    * \name Trigonometric operations.
    */
   /*@{*/
   ir_unop_sin,
   ir_unop_cos,
   /*@}*/

   /**
    * \name Partial derivatives.
    */
   /*@{*/
   ir_unop_dFdx,
   ir_unop_dFdy,
   /*@}*/

   ir_binop_add,
   ir_binop_sub,
   ir_binop_mul,
   ir_binop_div,
   ir_binop_mod,

   /**
    * \name Binary comparison operators
    */
   /*@{*/
   ir_binop_less,
   ir_binop_greater,
   ir_binop_lequal,
   ir_binop_gequal,
   ir_binop_equal,
   ir_binop_nequal,
   /*@}*/

   /**
    * \name Bit-wise binary operations.
    */
   /*@{*/
   ir_binop_lshift,
   ir_binop_rshift,
   ir_binop_bit_and,
   ir_binop_bit_xor,
   ir_binop_bit_or,
   /*@}*/

   ir_binop_logic_and,
   ir_binop_logic_xor,
   ir_binop_logic_or,

   ir_binop_dot,
   ir_binop_min,
   ir_binop_max,

   ir_binop_pow
};

class ir_expression : public ir_rvalue {
public:
   ir_expression(int op, const struct glsl_type *type,
		 ir_rvalue *, ir_rvalue *);

   virtual ir_instruction *clone(struct hash_table *ht) const;

   static unsigned int get_num_operands(ir_expression_operation);
   unsigned int get_num_operands() const
   {
      return get_num_operands(operation);
   }

   /**
    * Return a string representing this expression's operator.
    */
   const char *operator_string();

   /**
    * Do a reverse-lookup to translate the given string into an operator.
    */
   static ir_expression_operation get_operator(const char *);

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   ir_expression_operation operation;
   ir_rvalue *operands[2];
};


/**
 * IR instruction representing a function call
 */
class ir_call : public ir_rvalue {
public:
   ir_call(const ir_function_signature *callee, exec_list *actual_parameters)
      : callee(callee)
   {
      assert(callee->return_type != NULL);
      type = callee->return_type;
      actual_parameters->move_nodes_to(& this->actual_parameters);
   }

   virtual ir_instruction *clone(struct hash_table *ht) const;

   virtual ir_call *as_call()
   {
      return this;
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   /**
    * Get a generic ir_call object when an error occurs
    */
   static ir_call *get_error_instruction();

   /**
    * Get an iterator for the set of acutal parameters
    */
   exec_list_iterator iterator()
   {
      return actual_parameters.iterator();
   }

   /**
    * Get the name of the function being called.
    */
   const char *callee_name() const
   {
      return callee->function_name();
   }

   const ir_function_signature *get_callee()
   {
      return callee;
   }

   /**
    * Generates an inline version of the function before @ir,
    * returning the return value of the function.
    */
   ir_rvalue *generate_inline(ir_instruction *ir);

private:
   ir_call()
      : callee(NULL)
   {
      /* empty */
   }

   const ir_function_signature *callee;

   /* List of ir_rvalue of paramaters passed in this call. */
   exec_list actual_parameters;
};


/**
 * \name Jump-like IR instructions.
 *
 * These include \c break, \c continue, \c return, and \c discard.
 */
/*@{*/
class ir_jump : public ir_instruction {
protected:
   ir_jump()
   {
      /* empty */
   }
};

class ir_return : public ir_jump {
public:
   ir_return()
      : value(NULL)
   {
      /* empty */
   }

   ir_return(ir_rvalue *value)
      : value(value)
   {
      /* empty */
   }

   virtual ir_instruction *clone(struct hash_table *) const;

   virtual ir_return *as_return()
   {
      return this;
   }

   ir_rvalue *get_value() const
   {
      return value;
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   ir_rvalue *value;
};


/**
 * Jump instructions used inside loops
 *
 * These include \c break and \c continue.  The \c break within a loop is
 * different from the \c break within a switch-statement.
 *
 * \sa ir_switch_jump
 */
class ir_loop_jump : public ir_jump {
public:
   enum jump_mode {
      jump_break,
      jump_continue
   };

   ir_loop_jump(jump_mode mode)
      : mode(mode)
   {
      /* empty */
   }

   virtual ir_instruction *clone(struct hash_table *) const;

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   bool is_break() const
   {
      return mode == jump_break;
   }

   bool is_continue() const
   {
      return mode == jump_continue;
   }

private:
   /** Mode selector for the jump instruction. */
   enum jump_mode mode;
};
/*@}*/


/**
 * Texture sampling opcodes used in ir_texture
 */
enum ir_texture_opcode {
   ir_tex,		/* Regular texture look-up */
   ir_txb,		/* Texture look-up with LOD bias */
   ir_txl,		/* Texture look-up with explicit LOD */
   ir_txd,		/* Texture look-up with partial derivatvies */
   ir_txf		/* Texel fetch with explicit LOD */
};


/**
 * IR instruction to sample a texture
 *
 * The specific form of the IR instruction depends on the \c mode value
 * selected from \c ir_texture_opcodes.  In the printed IR, these will
 * appear as:
 *
 *                              Texel offset
 *                              |       Projection divisor
 *                              |       |   Shadow comparitor
 *                              |       |   |
 *                              v       v   v
 * (tex (sampler) (coordinate) (0 0 0) (1) ( ))
 * (txb (sampler) (coordinate) (0 0 0) (1) ( ) (bias))
 * (txl (sampler) (coordinate) (0 0 0) (1) ( ) (lod))
 * (txd (sampler) (coordinate) (0 0 0) (1) ( ) (dPdx dPdy))
 * (txf (sampler) (coordinate) (0 0 0)         (lod))
 */
class ir_texture : public ir_rvalue {
public:
   ir_texture(enum ir_texture_opcode op)
      : op(op), projector(NULL), shadow_comparitor(NULL)
   {
      /* empty */
   }

   virtual ir_instruction *clone(struct hash_table *) const;

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   /**
    * Return a string representing the ir_texture_opcode.
    */
   const char *opcode_string();

   /** Set the sampler and infer the type. */
   void set_sampler(ir_dereference *sampler);

   /**
    * Do a reverse-lookup to translate a string into an ir_texture_opcode.
    */
   static ir_texture_opcode get_opcode(const char *);

   enum ir_texture_opcode op;

   /** Sampler to use for the texture access. */
   ir_dereference *sampler;

   /** Texture coordinate to sample */
   ir_rvalue *coordinate;

   /**
    * Value used for projective divide.
    *
    * If there is no projective divide (the common case), this will be
    * \c NULL.  Optimization passes should check for this to point to a constant
    * of 1.0 and replace that with \c NULL.
    */
   ir_rvalue *projector;

   /**
    * Coordinate used for comparison on shadow look-ups.
    *
    * If there is no shadow comparison, this will be \c NULL.  For the
    * \c ir_txf opcode, this *must* be \c NULL.
    */
   ir_rvalue *shadow_comparitor;

   /** Explicit texel offsets. */
   signed char offsets[3];

   union {
      ir_rvalue *lod;		/**< Floating point LOD */
      ir_rvalue *bias;		/**< Floating point LOD bias */
      struct {
	 ir_rvalue *dPdx;	/**< Partial derivative of coordinate wrt X */
	 ir_rvalue *dPdy;	/**< Partial derivative of coordinate wrt Y */
      } grad;
   } lod_info;
};


struct ir_swizzle_mask {
   unsigned x:2;
   unsigned y:2;
   unsigned z:2;
   unsigned w:2;

   /**
    * Number of components in the swizzle.
    */
   unsigned num_components:3;

   /**
    * Does the swizzle contain duplicate components?
    *
    * L-value swizzles cannot contain duplicate components.
    */
   unsigned has_duplicates:1;
};


class ir_swizzle : public ir_rvalue {
public:
   ir_swizzle(ir_rvalue *, unsigned x, unsigned y, unsigned z, unsigned w,
              unsigned count);
   ir_swizzle(ir_rvalue *val, ir_swizzle_mask mask);

   virtual ir_instruction *clone(struct hash_table *) const;

   virtual ir_swizzle *as_swizzle()
   {
      return this;
   }

   /**
    * Construct an ir_swizzle from the textual representation.  Can fail.
    */
   static ir_swizzle *create(ir_rvalue *, const char *, unsigned vector_length);

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   bool is_lvalue()
   {
      return val->is_lvalue() && !mask.has_duplicates;
   }

   /**
    * Get the variable that is ultimately referenced by an r-value
    */
   virtual ir_variable *variable_referenced();

   ir_rvalue *val;
   ir_swizzle_mask mask;
};


class ir_dereference : public ir_rvalue {
public:
   virtual ir_dereference *as_dereference()
   {
      return this;
   }

   bool is_lvalue();

   /**
    * Get the variable that is ultimately referenced by an r-value
    */
   virtual ir_variable *variable_referenced() = 0;
};


class ir_dereference_variable : public ir_dereference {
public:
   ir_dereference_variable(ir_variable *var);

   virtual ir_instruction *clone(struct hash_table *) const;

   /**
    * Get the variable that is ultimately referenced by an r-value
    */
   virtual ir_variable *variable_referenced()
   {
      return this->var;
   }

   virtual ir_variable *whole_variable_referenced()
   {
      /* ir_dereference_variable objects always dereference the entire
       * variable.  However, if this dereference is dereferenced by anything
       * else, the complete deferefernce chain is not a whole-variable
       * dereference.  This method should only be called on the top most
       * ir_rvalue in a dereference chain.
       */
      return this->var;
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   /**
    * Object being dereferenced.
    */
   ir_variable *var;
};


class ir_dereference_array : public ir_dereference {
public:
   ir_dereference_array(ir_rvalue *value, ir_rvalue *array_index);

   ir_dereference_array(ir_variable *var, ir_rvalue *array_index);

   virtual ir_instruction *clone(struct hash_table *) const;

   virtual ir_dereference_array *as_dereference_array()
   {
      return this;
   }

   /**
    * Get the variable that is ultimately referenced by an r-value
    */
   virtual ir_variable *variable_referenced()
   {
      return this->array->variable_referenced();
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   ir_rvalue *array;
   ir_rvalue *array_index;

private:
   void set_array(ir_rvalue *value);
};


class ir_dereference_record : public ir_dereference {
public:
   ir_dereference_record(ir_rvalue *value, const char *field);

   ir_dereference_record(ir_variable *var, const char *field);

   virtual ir_instruction *clone(struct hash_table *) const;

   /**
    * Get the variable that is ultimately referenced by an r-value
    */
   virtual ir_variable *variable_referenced()
   {
      return this->record->variable_referenced();
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   ir_rvalue *record;
   const char *field;
};


/**
 * Data stored in an ir_constant
 */
union ir_constant_data {
      unsigned u[16];
      int i[16];
      float f[16];
      bool b[16];
};


class ir_constant : public ir_rvalue {
public:
   ir_constant(const struct glsl_type *type, const ir_constant_data *data);
   ir_constant(bool b);
   ir_constant(unsigned int u);
   ir_constant(int i);
   ir_constant(float f);

   /**
    * Construct an ir_constant from a list of ir_constant values
    */
   ir_constant(const struct glsl_type *type, exec_list *values);

   /**
    * Construct an ir_constant from a scalar component of another ir_constant
    *
    * The new \c ir_constant inherits the type of the component from the
    * source constant.
    *
    * \note
    * In the case of a matrix constant, the new constant is a scalar, \b not
    * a vector.
    */
   ir_constant(const ir_constant *c, unsigned i);

   virtual ir_instruction *clone(struct hash_table *) const;

   virtual ir_constant *as_constant()
   {
      return this;
   }

   virtual void accept(ir_visitor *v)
   {
      v->visit(this);
   }

   virtual ir_visitor_status accept(ir_hierarchical_visitor *);

   /**
    * Get a particular component of a constant as a specific type
    *
    * This is useful, for example, to get a value from an integer constant
    * as a float or bool.  This appears frequently when constructors are
    * called with all constant parameters.
    */
   /*@{*/
   bool get_bool_component(unsigned i) const;
   float get_float_component(unsigned i) const;
   int get_int_component(unsigned i) const;
   unsigned get_uint_component(unsigned i) const;
   /*@}*/

   ir_constant *get_record_field(const char *name);

   /**
    * Determine whether a constant has the same value as another constant
    */
   bool has_value(const ir_constant *) const;

   /**
    * Value of the constant.
    *
    * The field used to back the values supplied by the constant is determined
    * by the type associated with the \c ir_instruction.  Constants may be
    * scalars, vectors, or matrices.
    */
   union ir_constant_data value;

   exec_list components;

private:
   /**
    * Parameterless constructor only used by the clone method
    */
   ir_constant(void);
};

void
visit_exec_list(exec_list *list, ir_visitor *visitor);

void validate_ir_tree(exec_list *instructions);

extern void
_mesa_glsl_initialize_variables(exec_list *instructions,
				struct _mesa_glsl_parse_state *state);

extern void
_mesa_glsl_initialize_functions(exec_list *instructions,
				struct _mesa_glsl_parse_state *state);

#endif /* IR_H */