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 ralloc-based new need not call delete. It's
  53     * easier to just ralloc_free 'ctx' (or any of its ancestors). */
  54    static void* operator new(size_t size, void *ctx)
  55    {
  56       void *node;
  57
  58       node = rzalloc_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     * ralloc_free in that case. */
  66    static void operator delete(void *table)
  67    {
  68       ralloc_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_none = 0, /**< Absence of precision qualifier. */
 322    ast_precision_high,
 323    ast_precision_medium,
 324    ast_precision_low
 325 };
 326
 327 struct ast_type_qualifier {
 328    union {
 329       struct {
 330          unsigned invariant:1;
 331          unsigned constant:1;
 332          unsigned attribute:1;
 333          unsigned varying:1;
 334          unsigned in:1;
 335          unsigned out:1;
 336          unsigned centroid:1;
 337          unsigned uniform:1;
 338          unsigned smooth:1;
 339          unsigned flat:1;
 340          unsigned noperspective:1;
 341
 342          /** \name Layout qualifiers for GL_ARB_fragment_coord_conventions */
 343          /*@{*/
 344          unsigned origin_upper_left:1;
 345          unsigned pixel_center_integer:1;
 346          /*@}*/
 347
 348          /**
 349           * Flag set if GL_ARB_explicit_attrib_location "location" layout
 350           * qualifier is used.
 351           */
 352          unsigned explicit_location:1;
 353
 354          /** \name Layout qualifiers for GL_AMD_conservative_depth */
 355          /** \{ */
 356          unsigned depth_any:1;
 357          unsigned depth_greater:1;
 358          unsigned depth_less:1;
 359          unsigned depth_unchanged:1;
 360          /** \} */
 361       }
 362       /** \brief Set of flags, accessed by name. */
 363       q;
 364
 365       /** \brief Set of flags, accessed as a bitmask. */
 366       unsigned i;
 367    } flags;
 368
 369    /**
 370     * Location specified via GL_ARB_explicit_attrib_location layout
 371     *
 372     * \note
 373     * This field is only valid if \c explicit_location is set.
 374     */
 375    int location;
 376
 377    /**
 378     * Return true if and only if an interpolation qualifier is present.
 379     */
 380    bool has_interpolation() const;
 381
 382    /**
 383     * \brief Return string representation of interpolation qualifier.
 384     *
 385     * If an interpolation qualifier is present, then return that qualifier's
 386     * string representation. Otherwise, return null. For example, if the
 387     * noperspective bit is set, then this returns "noperspective".
 388     *
 389     * If multiple interpolation qualifiers are somehow present, then the
 390     * returned string is undefined but not null.
 391     */
 392    const char *interpolation_string() const;
 393 };
 394
 395 class ast_struct_specifier : public ast_node {
 396 public:
 397    ast_struct_specifier(char *identifier, ast_node *declarator_list);
 398    virtual void print(void) const;
 399
 400    virtual ir_rvalue *hir(exec_list *instructions,
 401                           struct _mesa_glsl_parse_state *state);
 402
 403    char *name;
 404    exec_list declarations;
 405 };
 406
 407
 408 enum ast_types {
 409    ast_void,
 410    ast_float,
 411    ast_int,
 412    ast_uint,
 413    ast_bool,
 414    ast_vec2,
 415    ast_vec3,
 416    ast_vec4,
 417    ast_bvec2,
 418    ast_bvec3,
 419    ast_bvec4,
 420    ast_ivec2,
 421    ast_ivec3,
 422    ast_ivec4,
 423    ast_uvec2,
 424    ast_uvec3,
 425    ast_uvec4,
 426    ast_mat2,
 427    ast_mat2x3,
 428    ast_mat2x4,
 429    ast_mat3x2,
 430    ast_mat3,
 431    ast_mat3x4,
 432    ast_mat4x2,
 433    ast_mat4x3,
 434    ast_mat4,
 435    ast_sampler1d,
 436    ast_sampler2d,
 437    ast_sampler2drect,
 438    ast_sampler3d,
 439    ast_samplercube,
 440    ast_samplerexternaloes,
 441    ast_sampler1dshadow,
 442    ast_sampler2dshadow,
 443    ast_sampler2drectshadow,
 444    ast_samplercubeshadow,
 445    ast_sampler1darray,
 446    ast_sampler2darray,
 447    ast_sampler1darrayshadow,
 448    ast_sampler2darrayshadow,
 449    ast_isampler1d,
 450    ast_isampler2d,
 451    ast_isampler3d,
 452    ast_isamplercube,
 453    ast_isampler1darray,
 454    ast_isampler2darray,
 455    ast_usampler1d,
 456    ast_usampler2d,
 457    ast_usampler3d,
 458    ast_usamplercube,
 459    ast_usampler1darray,
 460    ast_usampler2darray,
 461
 462    ast_struct,
 463    ast_type_name
 464 };
 465
 466
 467 class ast_type_specifier : public ast_node {
 468 public:
 469    ast_type_specifier(int specifier);
 470
 471    /** Construct a type specifier from a type name */
 472    ast_type_specifier(const char *name)
 473       : type_specifier(ast_type_name), type_name(name), structure(NULL),
 474         is_array(false), array_size(NULL), precision(ast_precision_none),
 475         is_precision_statement(false)
 476    {
 477       /* empty */
 478    }
 479
 480    /** Construct a type specifier from a structure definition */
 481    ast_type_specifier(ast_struct_specifier *s)
 482       : type_specifier(ast_struct), type_name(s->name), structure(s),
 483         is_array(false), array_size(NULL), precision(ast_precision_none),
 484         is_precision_statement(false)
 485    {
 486       /* empty */
 487    }
 488
 489    const struct glsl_type *glsl_type(const char **name,
 490                                      struct _mesa_glsl_parse_state *state)
 491       const;
 492
 493    virtual void print(void) const;
 494
 495    ir_rvalue *hir(exec_list *, struct _mesa_glsl_parse_state *);
 496
 497    enum ast_types type_specifier;
 498
 499    const char *type_name;
 500    ast_struct_specifier *structure;
 501
 502    int is_array;
 503    ast_expression *array_size;
 504
 505    unsigned precision:2;
 506
 507    bool is_precision_statement;
 508 };
 509
 510
 511 class ast_fully_specified_type : public ast_node {
 512 public:
 513    virtual void print(void) const;
 514    bool has_qualifiers() const;
 515
 516    ast_type_qualifier qualifier;
 517    ast_type_specifier *specifier;
 518 };
 519
 520
 521 class ast_declarator_list : public ast_node {
 522 public:
 523    ast_declarator_list(ast_fully_specified_type *);
 524    virtual void print(void) const;
 525
 526    virtual ir_rvalue *hir(exec_list *instructions,
 527                           struct _mesa_glsl_parse_state *state);
 528
 529    ast_fully_specified_type *type;
 530    exec_list declarations;
 531
 532    /**
 533     * Special flag for vertex shader "invariant" declarations.
 534     *
 535     * Vertex shaders can contain "invariant" variable redeclarations that do
 536     * not include a type.  For example, "invariant gl_Position;".  This flag
 537     * is used to note these cases when no type is specified.
 538     */
 539    int invariant;
 540 };
 541
 542
 543 class ast_parameter_declarator : public ast_node {
 544 public:
 545    ast_parameter_declarator()
 546    {
 547       this->identifier = NULL;
 548       this->is_array = false;
 549       this->array_size = 0;
 550    }
 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 *type;
 558    char *identifier;
 559    int is_array;
 560    ast_expression *array_size;
 561
 562    static void parameters_to_hir(exec_list *ast_parameters,
 563                                  bool formal, exec_list *ir_parameters,
 564                                  struct _mesa_glsl_parse_state *state);
 565
 566 private:
 567    /** Is this parameter declaration part of a formal parameter list? */
 568    bool formal_parameter;
 569
 570    /**
 571     * Is this parameter 'void' type?
 572     *
 573     * This field is set by \c ::hir.
 574     */
 575    bool is_void;
 576 };
 577
 578
 579 class ast_function : public ast_node {
 580 public:
 581    ast_function(void);
 582
 583    virtual void print(void) const;
 584
 585    virtual ir_rvalue *hir(exec_list *instructions,
 586                           struct _mesa_glsl_parse_state *state);
 587
 588    ast_fully_specified_type *return_type;
 589    char *identifier;
 590
 591    exec_list parameters;
 592
 593 private:
 594    /**
 595     * Is this prototype part of the function definition?
 596     *
 597     * Used by ast_function_definition::hir to process the parameters, etc.
 598     * of the function.
 599     *
 600     * \sa ::hir
 601     */
 602    bool is_definition;
 603
 604    /**
 605     * Function signature corresponding to this function prototype instance
 606     *
 607     * Used by ast_function_definition::hir to process the parameters, etc.
 608     * of the function.
 609     *
 610     * \sa ::hir
 611     */
 612    class ir_function_signature *signature;
 613
 614    friend class ast_function_definition;
 615 };
 616
 617
 618 class ast_expression_statement : public ast_node {
 619 public:
 620    ast_expression_statement(ast_expression *);
 621    virtual void print(void) const;
 622
 623    virtual ir_rvalue *hir(exec_list *instructions,
 624                           struct _mesa_glsl_parse_state *state);
 625
 626    ast_expression *expression;
 627 };
 628
 629
 630 class ast_case_label : public ast_node {
 631 public:
 632    ast_case_label(ast_expression *test_value);
 633    virtual void print(void) const;
 634
 635    virtual ir_rvalue *hir(exec_list *instructions,
 636                           struct _mesa_glsl_parse_state *state);
 637
 638    /**
 639     * An test value of NULL means 'default'.
 640     */
 641    ast_expression *test_value;
 642 };
 643
 644
 645 class ast_case_label_list : public ast_node {
 646 public:
 647    ast_case_label_list(void);
 648    virtual void print(void) const;
 649
 650    virtual ir_rvalue *hir(exec_list *instructions,
 651                           struct _mesa_glsl_parse_state *state);
 652
 653    /**
 654     * A list of case labels.
 655     */
 656    exec_list labels;
 657 };
 658
 659
 660 class ast_case_statement : public ast_node {
 661 public:
 662    ast_case_statement(ast_case_label_list *labels);
 663    virtual void print(void) const;
 664
 665    virtual ir_rvalue *hir(exec_list *instructions,
 666                           struct _mesa_glsl_parse_state *state);
 667
 668    ast_case_label_list *labels;
 669
 670    /**
 671     * A list of statements.
 672     */
 673    exec_list stmts;
 674 };
 675
 676
 677 class ast_case_statement_list : public ast_node {
 678 public:
 679    ast_case_statement_list(void);
 680    virtual void print(void) const;
 681
 682    virtual ir_rvalue *hir(exec_list *instructions,
 683                           struct _mesa_glsl_parse_state *state);
 684
 685    /**
 686     * A list of cases.
 687     */
 688    exec_list cases;
 689 };
 690
 691
 692 class ast_switch_body : public ast_node {
 693 public:
 694    ast_switch_body(ast_case_statement_list *stmts);
 695    virtual void print(void) const;
 696
 697    virtual ir_rvalue *hir(exec_list *instructions,
 698                           struct _mesa_glsl_parse_state *state);
 699
 700    ast_case_statement_list *stmts;
 701 };
 702
 703
 704 class ast_selection_statement : public ast_node {
 705 public:
 706    ast_selection_statement(ast_expression *condition,
 707                            ast_node *then_statement,
 708                            ast_node *else_statement);
 709    virtual void print(void) const;
 710
 711    virtual ir_rvalue *hir(exec_list *instructions,
 712                           struct _mesa_glsl_parse_state *state);
 713
 714    ast_expression *condition;
 715    ast_node *then_statement;
 716    ast_node *else_statement;
 717 };
 718
 719
 720 class ast_switch_statement : public ast_node {
 721 public:
 722    ast_switch_statement(ast_expression *test_expression,
 723                         ast_node *body);
 724    virtual void print(void) const;
 725
 726    virtual ir_rvalue *hir(exec_list *instructions,
 727                           struct _mesa_glsl_parse_state *state);
 728
 729    ast_expression *test_expression;
 730    ast_node *body;
 731
 732 protected:
 733    void test_to_hir(exec_list *, struct _mesa_glsl_parse_state *);
 734 };
 735
 736 class ast_iteration_statement : public ast_node {
 737 public:
 738    ast_iteration_statement(int mode, ast_node *init, ast_node *condition,
 739                            ast_expression *rest_expression, ast_node *body);
 740
 741    virtual void print(void) const;
 742
 743    virtual ir_rvalue *hir(exec_list *, struct _mesa_glsl_parse_state *);
 744
 745    enum ast_iteration_modes {
 746       ast_for,
 747       ast_while,
 748       ast_do_while
 749    } mode;
 750
 751
 752    ast_node *init_statement;
 753    ast_node *condition;
 754    ast_expression *rest_expression;
 755
 756    ast_node *body;
 757
 758 private:
 759    /**
 760     * Generate IR from the condition of a loop
 761     *
 762     * This is factored out of ::hir because some loops have the condition
 763     * test at the top (for and while), and others have it at the end (do-while).
 764     */
 765    void condition_to_hir(class ir_loop *, struct _mesa_glsl_parse_state *);
 766 };
 767
 768
 769 class ast_jump_statement : public ast_node {
 770 public:
 771    ast_jump_statement(int mode, ast_expression *return_value);
 772    virtual void print(void) const;
 773
 774    virtual ir_rvalue *hir(exec_list *instructions,
 775                           struct _mesa_glsl_parse_state *state);
 776
 777    enum ast_jump_modes {
 778       ast_continue,
 779       ast_break,
 780       ast_return,
 781       ast_discard
 782    } mode;
 783
 784    ast_expression *opt_return_value;
 785 };
 786
 787
 788 class ast_function_definition : public ast_node {
 789 public:
 790    virtual void print(void) const;
 791
 792    virtual ir_rvalue *hir(exec_list *instructions,
 793                           struct _mesa_glsl_parse_state *state);
 794
 795    ast_function *prototype;
 796    ast_compound_statement *body;
 797 };
 798 /*@}*/
 799
 800 extern void
 801 _mesa_ast_to_hir(exec_list *instructions, struct _mesa_glsl_parse_state *state);
 802
 803 extern ir_rvalue *
 804 _mesa_ast_field_selection_to_hir(const ast_expression *expr,
 805                                  exec_list *instructions,
 806                                  struct _mesa_glsl_parse_state *state);
 807
 808 void
 809 emit_function(_mesa_glsl_parse_state *state, ir_function *f);
 810
 811 #endif /* AST_H */