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    union {
 328       struct {
 329          unsigned invariant:1;
 330          unsigned constant:1;
 331          unsigned attribute:1;
 332          unsigned varying:1;
 333          unsigned in:1;
 334          unsigned out:1;
 335          unsigned centroid:1;
 336          unsigned uniform:1;
 337          unsigned smooth:1;
 338          unsigned flat:1;
 339          unsigned noperspective:1;
 340
 341          /** \name Layout qualifiers for GL_ARB_fragment_coord_conventions */
 342          /*@{*/
 343          unsigned origin_upper_left:1;
 344          unsigned pixel_center_integer:1;
 345          /*@}*/
 346
 347          /**
 348           * Flag set if GL_ARB_explicit_attrib_location "location" layout
 349           * qualifier is used.
 350           */
 351          unsigned explicit_location:1;
 352       }
 353       /** \brief Set of flags, accessed by name. */
 354       q;
 355
 356       /** \brief Set of flags, accessed as a bitmask. */
 357       unsigned i;
 358    } flags;
 359
 360    /**
 361     * Location specified via GL_ARB_explicit_attrib_location layout
 362     *
 363     * \note
 364     * This field is only valid if \c explicit_location is set.
 365     */
 366    unsigned location;
 367 };
 368
 369 class ast_struct_specifier : public ast_node {
 370 public:
 371    ast_struct_specifier(char *identifier, ast_node *declarator_list);
 372    virtual void print(void) const;
 373
 374    virtual ir_rvalue *hir(exec_list *instructions,
 375                           struct _mesa_glsl_parse_state *state);
 376
 377    char *name;
 378    exec_list declarations;
 379 };
 380
 381
 382 enum ast_types {
 383    ast_void,
 384    ast_float,
 385    ast_int,
 386    ast_uint,
 387    ast_bool,
 388    ast_vec2,
 389    ast_vec3,
 390    ast_vec4,
 391    ast_bvec2,
 392    ast_bvec3,
 393    ast_bvec4,
 394    ast_ivec2,
 395    ast_ivec3,
 396    ast_ivec4,
 397    ast_uvec2,
 398    ast_uvec3,
 399    ast_uvec4,
 400    ast_mat2,
 401    ast_mat2x3,
 402    ast_mat2x4,
 403    ast_mat3x2,
 404    ast_mat3,
 405    ast_mat3x4,
 406    ast_mat4x2,
 407    ast_mat4x3,
 408    ast_mat4,
 409    ast_sampler1d,
 410    ast_sampler2d,
 411    ast_sampler2drect,
 412    ast_sampler3d,
 413    ast_samplercube,
 414    ast_sampler1dshadow,
 415    ast_sampler2dshadow,
 416    ast_sampler2drectshadow,
 417    ast_samplercubeshadow,
 418    ast_sampler1darray,
 419    ast_sampler2darray,
 420    ast_sampler1darrayshadow,
 421    ast_sampler2darrayshadow,
 422    ast_isampler1d,
 423    ast_isampler2d,
 424    ast_isampler3d,
 425    ast_isamplercube,
 426    ast_isampler1darray,
 427    ast_isampler2darray,
 428    ast_usampler1d,
 429    ast_usampler2d,
 430    ast_usampler3d,
 431    ast_usamplercube,
 432    ast_usampler1darray,
 433    ast_usampler2darray,
 434
 435    ast_struct,
 436    ast_type_name
 437 };
 438
 439
 440 class ast_type_specifier : public ast_node {
 441 public:
 442    ast_type_specifier(int specifier);
 443
 444    /** Construct a type specifier from a type name */
 445    ast_type_specifier(const char *name)
 446       : type_specifier(ast_type_name), type_name(name), structure(NULL),
 447         is_array(false), array_size(NULL), precision(ast_precision_high)
 448    {
 449       /* empty */
 450    }
 451
 452    /** Construct a type specifier from a structure definition */
 453    ast_type_specifier(ast_struct_specifier *s)
 454       : type_specifier(ast_struct), type_name(s->name), structure(s),
 455         is_array(false), array_size(NULL), precision(ast_precision_high)
 456    {
 457       /* empty */
 458    }
 459
 460    const struct glsl_type *glsl_type(const char **name,
 461                                      struct _mesa_glsl_parse_state *state)
 462       const;
 463
 464    virtual void print(void) const;
 465
 466    ir_rvalue *hir(exec_list *, struct _mesa_glsl_parse_state *);
 467
 468    enum ast_types type_specifier;
 469
 470    const char *type_name;
 471    ast_struct_specifier *structure;
 472
 473    int is_array;
 474    ast_expression *array_size;
 475
 476    unsigned precision:2;
 477 };
 478
 479
 480 class ast_fully_specified_type : public ast_node {
 481 public:
 482    virtual void print(void) const;
 483    bool has_qualifiers() const;
 484
 485    ast_type_qualifier qualifier;
 486    ast_type_specifier *specifier;
 487 };
 488
 489
 490 class ast_declarator_list : public ast_node {
 491 public:
 492    ast_declarator_list(ast_fully_specified_type *);
 493    virtual void print(void) const;
 494
 495    virtual ir_rvalue *hir(exec_list *instructions,
 496                           struct _mesa_glsl_parse_state *state);
 497
 498    ast_fully_specified_type *type;
 499    exec_list declarations;
 500
 501    /**
 502     * Special flag for vertex shader "invariant" declarations.
 503     *
 504     * Vertex shaders can contain "invariant" variable redeclarations that do
 505     * not include a type.  For example, "invariant gl_Position;".  This flag
 506     * is used to note these cases when no type is specified.
 507     */
 508    int invariant;
 509 };
 510
 511
 512 class ast_parameter_declarator : public ast_node {
 513 public:
 514    ast_parameter_declarator()
 515    {
 516       this->identifier = NULL;
 517       this->is_array = false;
 518       this->array_size = 0;
 519    }
 520
 521    virtual void print(void) const;
 522
 523    virtual ir_rvalue *hir(exec_list *instructions,
 524                           struct _mesa_glsl_parse_state *state);
 525
 526    ast_fully_specified_type *type;
 527    char *identifier;
 528    int is_array;
 529    ast_expression *array_size;
 530
 531    static void parameters_to_hir(exec_list *ast_parameters,
 532                                  bool formal, exec_list *ir_parameters,
 533                                  struct _mesa_glsl_parse_state *state);
 534
 535 private:
 536    /** Is this parameter declaration part of a formal parameter list? */
 537    bool formal_parameter;
 538
 539    /**
 540     * Is this parameter 'void' type?
 541     *
 542     * This field is set by \c ::hir.
 543     */
 544    bool is_void;
 545 };
 546
 547
 548 class ast_function : public ast_node {
 549 public:
 550    ast_function(void);
 551
 552    virtual void print(void) const;
 553
 554    virtual ir_rvalue *hir(exec_list *instructions,
 555                           struct _mesa_glsl_parse_state *state);
 556
 557    ast_fully_specified_type *return_type;
 558    char *identifier;
 559
 560    exec_list parameters;
 561
 562 private:
 563    /**
 564     * Is this prototype part of the function definition?
 565     *
 566     * Used by ast_function_definition::hir to process the parameters, etc.
 567     * of the function.
 568     *
 569     * \sa ::hir
 570     */
 571    bool is_definition;
 572
 573    /**
 574     * Function signature corresponding to this function prototype instance
 575     *
 576     * Used by ast_function_definition::hir to process the parameters, etc.
 577     * of the function.
 578     *
 579     * \sa ::hir
 580     */
 581    class ir_function_signature *signature;
 582
 583    friend class ast_function_definition;
 584 };
 585
 586
 587 class ast_declaration_statement : public ast_node {
 588 public:
 589    ast_declaration_statement(void);
 590
 591    enum {
 592       ast_function,
 593       ast_declaration,
 594       ast_precision
 595    } mode;
 596
 597    union {
 598       class ast_function *function;
 599       ast_declarator_list *declarator;
 600       ast_type_specifier *type;
 601       ast_node *node;
 602    } declaration;
 603 };
 604
 605
 606 class ast_expression_statement : public ast_node {
 607 public:
 608    ast_expression_statement(ast_expression *);
 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 *expression;
 615 };
 616
 617
 618 class ast_case_label : public ast_node {
 619 public:
 620
 621    /**
 622     * An expression of NULL means 'default'.
 623     */
 624    ast_expression *expression;
 625 };
 626
 627 class ast_selection_statement : public ast_node {
 628 public:
 629    ast_selection_statement(ast_expression *condition,
 630                            ast_node *then_statement,
 631                            ast_node *else_statement);
 632    virtual void print(void) const;
 633
 634    virtual ir_rvalue *hir(exec_list *instructions,
 635                           struct _mesa_glsl_parse_state *state);
 636
 637    ast_expression *condition;
 638    ast_node *then_statement;
 639    ast_node *else_statement;
 640 };
 641
 642
 643 class ast_switch_statement : public ast_node {
 644 public:
 645    ast_expression *expression;
 646    exec_list statements;
 647 };
 648
 649 class ast_iteration_statement : public ast_node {
 650 public:
 651    ast_iteration_statement(int mode, ast_node *init, ast_node *condition,
 652                            ast_expression *rest_expression, ast_node *body);
 653
 654    virtual void print(void) const;
 655
 656    virtual ir_rvalue *hir(exec_list *, struct _mesa_glsl_parse_state *);
 657
 658    enum ast_iteration_modes {
 659       ast_for,
 660       ast_while,
 661       ast_do_while
 662    } mode;
 663
 664
 665    ast_node *init_statement;
 666    ast_node *condition;
 667    ast_expression *rest_expression;
 668
 669    ast_node *body;
 670
 671 private:
 672    /**
 673     * Generate IR from the condition of a loop
 674     *
 675     * This is factored out of ::hir because some loops have the condition
 676     * test at the top (for and while), and others have it at the end (do-while).
 677     */
 678    void condition_to_hir(class ir_loop *, struct _mesa_glsl_parse_state *);
 679 };
 680
 681
 682 class ast_jump_statement : public ast_node {
 683 public:
 684    ast_jump_statement(int mode, ast_expression *return_value);
 685    virtual void print(void) const;
 686
 687    virtual ir_rvalue *hir(exec_list *instructions,
 688                           struct _mesa_glsl_parse_state *state);
 689
 690    enum ast_jump_modes {
 691       ast_continue,
 692       ast_break,
 693       ast_return,
 694       ast_discard
 695    } mode;
 696
 697    ast_expression *opt_return_value;
 698 };
 699
 700
 701 class ast_function_definition : public ast_node {
 702 public:
 703    virtual void print(void) const;
 704
 705    virtual ir_rvalue *hir(exec_list *instructions,
 706                           struct _mesa_glsl_parse_state *state);
 707
 708    ast_function *prototype;
 709    ast_compound_statement *body;
 710 };
 711 /*@}*/
 712
 713 extern void
 714 _mesa_ast_to_hir(exec_list *instructions, struct _mesa_glsl_parse_state *state);
 715
 716 extern ir_rvalue *
 717 _mesa_ast_field_selection_to_hir(const ast_expression *expr,
 718                                  exec_list *instructions,
 719                                  struct _mesa_glsl_parse_state *state);
 720
 721 void
 722 emit_function(_mesa_glsl_parse_state *state, exec_list *instructions,
 723               ir_function *f);
 724
 725 #endif /* AST_H */