src/glsl/ast.h

   1 /* -*- c++ -*- */
   2 /*
   3  * Copyright © 2009 Intel Corporation
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software"),
   7  * to deal in the Software without restriction, including without limitation
   8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   9  * and/or sell copies of the Software, and to permit persons to whom the
  10  * Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice (including the next
  13  * paragraph) shall be included in all copies or substantial portions of the
  14  * Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  22  * DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 #pragma once
  26 #ifndef AST_H
  27 #define AST_H
  28
  29 #include "list.h"
  30 #include "glsl_parser_extras.h"
  31
  32 struct _mesa_glsl_parse_state;
  33
  34 struct YYLTYPE;
  35
  36 /**
  37  * \defgroup AST Abstract syntax tree node definitions
  38  *
  39  * An abstract syntax tree is generated by the parser.  This is a fairly
  40  * direct representation of the gramma derivation for the source program.
  41  * No symantic checking is done during the generation of the AST.  Only
  42  * syntactic checking is done.  Symantic checking is performed by a later
  43  * stage that converts the AST to a more generic intermediate representation.
  44  *
  45  *@{
  46  */
  47 /**
  48  * Base class of all abstract syntax tree nodes
  49  */
  50 class ast_node {
  51 public:
  52    /* Callers of this talloc-based new need not call delete. It's
  53     * easier to just talloc_free 'ctx' (or any of its ancestors). */
  54    static void* operator new(size_t size, void *ctx)
  55    {
  56       void *node;
  57
  58       node = talloc_zero_size(ctx, size);
  59       assert(node != NULL);
  60
  61       return node;
  62    }
  63
  64    /* If the user *does* call delete, that's OK, we will just
  65     * talloc_free in that case. */
  66    static void operator delete(void *table)
  67    {
  68       talloc_free(table);
  69    }
  70
  71    /**
  72     * Print an AST node in something approximating the original GLSL code
  73     */
  74    virtual void print(void) const;
  75
  76    /**
  77     * Convert the AST node to the high-level intermediate representation
  78     */
  79    virtual ir_rvalue *hir(exec_list *instructions,
  80                           struct _mesa_glsl_parse_state *state);
  81
  82    /**
  83     * Retrieve the source location of an AST node
  84     *
  85     * This function is primarily used to get the source position of an AST node
  86     * into a form that can be passed to \c _mesa_glsl_error.
  87     *
  88     * \sa _mesa_glsl_error, ast_node::set_location
  89     */
  90    struct YYLTYPE get_location(void) const
  91    {
  92       struct YYLTYPE locp;
  93
  94       locp.source = this->location.source;
  95       locp.first_line = this->location.line;
  96       locp.first_column = this->location.column;
  97       locp.last_line = locp.first_line;
  98       locp.last_column = locp.first_column;
  99
 100       return locp;
 101    }
 102
 103    /**
 104     * Set the source location of an AST node from a parser location
 105     *
 106     * \sa ast_node::get_location
 107     */
 108    void set_location(const struct YYLTYPE &locp)
 109    {
 110       this->location.source = locp.source;
 111       this->location.line = locp.first_line;
 112       this->location.column = locp.first_column;
 113    }
 114
 115    /**
 116     * Source location of the AST node.
 117     */
 118    struct {
 119       unsigned source;    /**< GLSL source number. */
 120       unsigned line;      /**< Line number within the source string. */
 121       unsigned column;    /**< Column in the line. */
 122    } location;
 123
 124    exec_node link;
 125
 126 protected:
 127    /**
 128     * The only constructor is protected so that only derived class objects can
 129     * be created.
 130     */
 131    ast_node(void);
 132 };
 133
 134
 135 /**
 136  * Operators for AST expression nodes.
 137  */
 138 enum ast_operators {
 139    ast_assign,
 140    ast_plus,        /**< Unary + operator. */
 141    ast_neg,
 142    ast_add,
 143    ast_sub,
 144    ast_mul,
 145    ast_div,
 146    ast_mod,
 147    ast_lshift,
 148    ast_rshift,
 149    ast_less,
 150    ast_greater,
 151    ast_lequal,
 152    ast_gequal,
 153    ast_equal,
 154    ast_nequal,
 155    ast_bit_and,
 156    ast_bit_xor,
 157    ast_bit_or,
 158    ast_bit_not,
 159    ast_logic_and,
 160    ast_logic_xor,
 161    ast_logic_or,
 162    ast_logic_not,
 163
 164    ast_mul_assign,
 165    ast_div_assign,
 166    ast_mod_assign,
 167    ast_add_assign,
 168    ast_sub_assign,
 169    ast_ls_assign,
 170    ast_rs_assign,
 171    ast_and_assign,
 172    ast_xor_assign,
 173    ast_or_assign,
 174
 175    ast_conditional,
 176
 177    ast_pre_inc,
 178    ast_pre_dec,
 179    ast_post_inc,
 180    ast_post_dec,
 181    ast_field_selection,
 182    ast_array_index,
 183
 184    ast_function_call,
 185
 186    ast_identifier,
 187    ast_int_constant,
 188    ast_uint_constant,
 189    ast_float_constant,
 190    ast_bool_constant,
 191
 192    ast_sequence
 193 };
 194
 195 /**
 196  * Representation of any sort of expression.
 197  */
 198 class ast_expression : public ast_node {
 199 public:
 200    ast_expression(int oper, ast_expression *,
 201                   ast_expression *, ast_expression *);
 202
 203    ast_expression(const char *identifier) :
 204       oper(ast_identifier)
 205    {
 206       subexpressions[0] = NULL;
 207       subexpressions[1] = NULL;
 208       subexpressions[2] = NULL;
 209       primary_expression.identifier = (char *) identifier;
 210    }
 211
 212    static const char *operator_string(enum ast_operators op);
 213
 214    virtual ir_rvalue *hir(exec_list *instructions,
 215                           struct _mesa_glsl_parse_state *state);
 216
 217    virtual void print(void) const;
 218
 219    enum ast_operators oper;
 220
 221    ast_expression *subexpressions[3];
 222
 223    union {
 224       char *identifier;
 225       int int_constant;
 226       float float_constant;
 227       unsigned uint_constant;
 228       int bool_constant;
 229    } primary_expression;
 230
 231
 232    /**
 233     * List of expressions for an \c ast_sequence or parameters for an
 234     * \c ast_function_call
 235     */
 236    exec_list expressions;
 237 };
 238
 239 class ast_expression_bin : public ast_expression {
 240 public:
 241    ast_expression_bin(int oper, ast_expression *, ast_expression *);
 242
 243    virtual void print(void) const;
 244 };
 245
 246 /**
 247  * Subclass of expressions for function calls
 248  */
 249 class ast_function_expression : public ast_expression {
 250 public:
 251    ast_function_expression(ast_expression *callee)
 252       : ast_expression(ast_function_call, callee,
 253                        NULL, NULL),
 254         cons(false)
 255    {
 256       /* empty */
 257    }
 258
 259    ast_function_expression(class ast_type_specifier *type)
 260       : ast_expression(ast_function_call, (ast_expression *) type,
 261                        NULL, NULL),
 262         cons(true)
 263    {
 264       /* empty */
 265    }
 266
 267    bool is_constructor() const
 268    {
 269       return cons;
 270    }
 271
 272    virtual ir_rvalue *hir(exec_list *instructions,
 273                           struct _mesa_glsl_parse_state *state);
 274
 275 private:
 276    /**
 277     * Is this function call actually a constructor?
 278     */
 279    bool cons;
 280 };
 281
 282
 283 /**
 284  * Number of possible operators for an ast_expression
 285  *
 286  * This is done as a define instead of as an additional value in the enum so
 287  * that the compiler won't generate spurious messages like "warning:
 288  * enumeration value ‘ast_num_operators’ not handled in switch"
 289  */
 290 #define AST_NUM_OPERATORS (ast_sequence + 1)
 291
 292
 293 class ast_compound_statement : public ast_node {
 294 public:
 295    ast_compound_statement(int new_scope, ast_node *statements);
 296    virtual void print(void) const;
 297
 298    virtual ir_rvalue *hir(exec_list *instructions,
 299                           struct _mesa_glsl_parse_state *state);
 300
 301    int new_scope;
 302    exec_list statements;
 303 };
 304
 305 class ast_declaration : public ast_node {
 306 public:
 307    ast_declaration(char *identifier, int is_array, ast_expression *array_size,
 308                    ast_expression *initializer);
 309    virtual void print(void) const;
 310
 311    char *identifier;
 312
 313    int is_array;
 314    ast_expression *array_size;
 315
 316    ast_expression *initializer;
 317 };
 318
 319
 320 enum {
 321    ast_precision_high = 0, /**< Default precision. */
 322    ast_precision_medium,
 323    ast_precision_low
 324 };
 325
 326 struct ast_type_qualifier {
 327    unsigned invariant:1;
 328    unsigned constant:1;
 329    unsigned attribute:1;
 330    unsigned varying:1;
 331    unsigned in:1;
 332    unsigned out:1;
 333    unsigned centroid:1;
 334    unsigned uniform:1;
 335    unsigned smooth:1;
 336    unsigned flat:1;
 337    unsigned noperspective:1;
 338
 339    /** \name Layout qualifiers for GL_ARB_fragment_coord_conventions */
 340    /*@{*/
 341    unsigned origin_upper_left:1;
 342    unsigned pixel_center_integer:1;
 343    /*@}*/
 344 };
 345
 346 class ast_struct_specifier : public ast_node {
 347 public:
 348    ast_struct_specifier(char *identifier, ast_node *declarator_list);
 349    virtual void print(void) const;
 350
 351    virtual ir_rvalue *hir(exec_list *instructions,
 352                           struct _mesa_glsl_parse_state *state);
 353
 354    char *name;
 355    exec_list declarations;
 356 };
 357
 358
 359 enum ast_types {
 360    ast_void,
 361    ast_float,
 362    ast_int,
 363    ast_uint,
 364    ast_bool,
 365    ast_vec2,
 366    ast_vec3,
 367    ast_vec4,
 368    ast_bvec2,
 369    ast_bvec3,
 370    ast_bvec4,
 371    ast_ivec2,
 372    ast_ivec3,
 373    ast_ivec4,
 374    ast_uvec2,
 375    ast_uvec3,
 376    ast_uvec4,
 377    ast_mat2,
 378    ast_mat2x3,
 379    ast_mat2x4,
 380    ast_mat3x2,
 381    ast_mat3,
 382    ast_mat3x4,
 383    ast_mat4x2,
 384    ast_mat4x3,
 385    ast_mat4,
 386    ast_sampler1d,
 387    ast_sampler2d,
 388    ast_sampler2drect,
 389    ast_sampler3d,
 390    ast_samplercube,
 391    ast_sampler1dshadow,
 392    ast_sampler2dshadow,
 393    ast_sampler2drectshadow,
 394    ast_samplercubeshadow,
 395    ast_sampler1darray,
 396    ast_sampler2darray,
 397    ast_sampler1darrayshadow,
 398    ast_sampler2darrayshadow,
 399    ast_isampler1d,
 400    ast_isampler2d,
 401    ast_isampler3d,
 402    ast_isamplercube,
 403    ast_isampler1darray,
 404    ast_isampler2darray,
 405    ast_usampler1d,
 406    ast_usampler2d,
 407    ast_usampler3d,
 408    ast_usamplercube,
 409    ast_usampler1darray,
 410    ast_usampler2darray,
 411
 412    ast_struct,
 413    ast_type_name
 414 };
 415
 416
 417 class ast_type_specifier : public ast_node {
 418 public:
 419    ast_type_specifier(int specifier);
 420
 421    /** Construct a type specifier from a type name */
 422    ast_type_specifier(const char *name)
 423       : type_specifier(ast_type_name), type_name(name), structure(NULL),
 424         is_array(false), array_size(NULL), precision(ast_precision_high)
 425    {
 426       /* empty */
 427    }
 428
 429    /** Construct a type specifier from a structure definition */
 430    ast_type_specifier(ast_struct_specifier *s)
 431       : type_specifier(ast_struct), type_name(s->name), structure(s),
 432         is_array(false), array_size(NULL), precision(ast_precision_high)
 433    {
 434       /* empty */
 435    }
 436
 437    const struct glsl_type *glsl_type(const char **name,
 438                                      struct _mesa_glsl_parse_state *state)
 439       const;
 440
 441    virtual void print(void) const;
 442
 443    ir_rvalue *hir(exec_list *, struct _mesa_glsl_parse_state *);
 444
 445    enum ast_types type_specifier;
 446
 447    const char *type_name;
 448    ast_struct_specifier *structure;
 449
 450    int is_array;
 451    ast_expression *array_size;
 452
 453    unsigned precision:2;
 454 };
 455
 456
 457 class ast_fully_specified_type : public ast_node {
 458 public:
 459    virtual void print(void) const;
 460    bool has_qualifiers() const;
 461
 462    ast_type_qualifier qualifier;
 463    ast_type_specifier *specifier;
 464 };
 465
 466
 467 class ast_declarator_list : public ast_node {
 468 public:
 469    ast_declarator_list(ast_fully_specified_type *);
 470    virtual void print(void) const;
 471
 472    virtual ir_rvalue *hir(exec_list *instructions,
 473                           struct _mesa_glsl_parse_state *state);
 474
 475    ast_fully_specified_type *type;
 476    exec_list declarations;
 477
 478    /**
 479     * Special flag for vertex shader "invariant" declarations.
 480     *
 481     * Vertex shaders can contain "invariant" variable redeclarations that do
 482     * not include a type.  For example, "invariant gl_Position;".  This flag
 483     * is used to note these cases when no type is specified.
 484     */
 485    int invariant;
 486 };
 487
 488
 489 class ast_parameter_declarator : public ast_node {
 490 public:
 491    ast_parameter_declarator()
 492    {
 493       this->identifier = NULL;
 494       this->is_array = false;
 495       this->array_size = 0;
 496    }
 497
 498    virtual void print(void) const;
 499
 500    virtual ir_rvalue *hir(exec_list *instructions,
 501                           struct _mesa_glsl_parse_state *state);
 502
 503    ast_fully_specified_type *type;
 504    char *identifier;
 505    int is_array;
 506    ast_expression *array_size;
 507
 508    static void parameters_to_hir(exec_list *ast_parameters,
 509                                  bool formal, exec_list *ir_parameters,
 510                                  struct _mesa_glsl_parse_state *state);
 511
 512 private:
 513    /** Is this parameter declaration part of a formal parameter list? */
 514    bool formal_parameter;
 515
 516    /**
 517     * Is this parameter 'void' type?
 518     *
 519     * This field is set by \c ::hir.
 520     */
 521    bool is_void;
 522 };
 523
 524
 525 class ast_function : public ast_node {
 526 public:
 527    ast_function(void);
 528
 529    virtual void print(void) const;
 530
 531    virtual ir_rvalue *hir(exec_list *instructions,
 532                           struct _mesa_glsl_parse_state *state);
 533
 534    ast_fully_specified_type *return_type;
 535    char *identifier;
 536
 537    exec_list parameters;
 538
 539 private:
 540    /**
 541     * Is this prototype part of the function definition?
 542     *
 543     * Used by ast_function_definition::hir to process the parameters, etc.
 544     * of the function.
 545     *
 546     * \sa ::hir
 547     */
 548    bool is_definition;
 549
 550    /**
 551     * Function signature corresponding to this function prototype instance
 552     *
 553     * Used by ast_function_definition::hir to process the parameters, etc.
 554     * of the function.
 555     *
 556     * \sa ::hir
 557     */
 558    class ir_function_signature *signature;
 559
 560    friend class ast_function_definition;
 561 };
 562
 563
 564 class ast_declaration_statement : public ast_node {
 565 public:
 566    ast_declaration_statement(void);
 567
 568    enum {
 569       ast_function,
 570       ast_declaration,
 571       ast_precision
 572    } mode;
 573
 574    union {
 575       class ast_function *function;
 576       ast_declarator_list *declarator;
 577       ast_type_specifier *type;
 578       ast_node *node;
 579    } declaration;
 580 };
 581
 582
 583 class ast_expression_statement : public ast_node {
 584 public:
 585    ast_expression_statement(ast_expression *);
 586    virtual void print(void) const;
 587
 588    virtual ir_rvalue *hir(exec_list *instructions,
 589                           struct _mesa_glsl_parse_state *state);
 590
 591    ast_expression *expression;
 592 };
 593
 594
 595 class ast_case_label : public ast_node {
 596 public:
 597
 598    /**
 599     * An expression of NULL means 'default'.
 600     */
 601    ast_expression *expression;
 602 };
 603
 604 class ast_selection_statement : public ast_node {
 605 public:
 606    ast_selection_statement(ast_expression *condition,
 607                            ast_node *then_statement,
 608                            ast_node *else_statement);
 609    virtual void print(void) const;
 610
 611    virtual ir_rvalue *hir(exec_list *instructions,
 612                           struct _mesa_glsl_parse_state *state);
 613
 614    ast_expression *condition;
 615    ast_node *then_statement;
 616    ast_node *else_statement;
 617 };
 618
 619
 620 class ast_switch_statement : public ast_node {
 621 public:
 622    ast_expression *expression;
 623    exec_list statements;
 624 };
 625
 626 class ast_iteration_statement : public ast_node {
 627 public:
 628    ast_iteration_statement(int mode, ast_node *init, ast_node *condition,
 629                            ast_expression *rest_expression, ast_node *body);
 630
 631    virtual void print(void) const;
 632
 633    virtual ir_rvalue *hir(exec_list *, struct _mesa_glsl_parse_state *);
 634
 635    enum ast_iteration_modes {
 636       ast_for,
 637       ast_while,
 638       ast_do_while
 639    } mode;
 640
 641
 642    ast_node *init_statement;
 643    ast_node *condition;
 644    ast_expression *rest_expression;
 645
 646    ast_node *body;
 647
 648 private:
 649    /**
 650     * Generate IR from the condition of a loop
 651     *
 652     * This is factored out of ::hir because some loops have the condition
 653     * test at the top (for and while), and others have it at the end (do-while).
 654     */
 655    void condition_to_hir(class ir_loop *, struct _mesa_glsl_parse_state *);
 656 };
 657
 658
 659 class ast_jump_statement : public ast_node {
 660 public:
 661    ast_jump_statement(int mode, ast_expression *return_value);
 662    virtual void print(void) const;
 663
 664    virtual ir_rvalue *hir(exec_list *instructions,
 665                           struct _mesa_glsl_parse_state *state);
 666
 667    enum ast_jump_modes {
 668       ast_continue,
 669       ast_break,
 670       ast_return,
 671       ast_discard
 672    } mode;
 673
 674    ast_expression *opt_return_value;
 675 };
 676
 677
 678 class ast_function_definition : public ast_node {
 679 public:
 680    virtual void print(void) const;
 681
 682    virtual ir_rvalue *hir(exec_list *instructions,
 683                           struct _mesa_glsl_parse_state *state);
 684
 685    ast_function *prototype;
 686    ast_compound_statement *body;
 687 };
 688 /*@}*/
 689
 690 extern void
 691 _mesa_ast_to_hir(exec_list *instructions, struct _mesa_glsl_parse_state *state);
 692
 693 extern ir_rvalue *
 694 _mesa_ast_field_selection_to_hir(const ast_expression *expr,
 695                                  exec_list *instructions,
 696                                  struct _mesa_glsl_parse_state *state);
 697
 698 #endif /* AST_H */