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      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 = identifier;
    210       this->non_lvalue_description = NULL;
    211    }
    212 
    213    static const char *operator_string(enum ast_operators op);
    214 
    215    virtual ir_rvalue *hir(exec_list *instructions,
    216 			  struct _mesa_glsl_parse_state *state);
    217 
    218    virtual void print(void) const;
    219 
    220    enum ast_operators oper;
    221 
    222    ast_expression *subexpressions[3];
    223 
    224    union {
    225       const char *identifier;
    226       int int_constant;
    227       float float_constant;
    228       unsigned uint_constant;
    229       int bool_constant;
    230    } primary_expression;
    231 
    232 
    233    /**
    234     * List of expressions for an \c ast_sequence or parameters for an
    235     * \c ast_function_call
    236     */
    237    exec_list expressions;
    238 
    239    /**
    240     * For things that can't be l-values, this describes what it is.
    241     *
    242     * This text is used by the code that generates IR for assignments to
    243     * detect and emit useful messages for assignments to some things that
    244     * can't be l-values.  For example, pre- or post-incerement expressions.
    245     *
    246     * \note
    247     * This pointer may be \c NULL.
    248     */
    249    const char *non_lvalue_description;
    250 };
    251 
    252 class ast_expression_bin : public ast_expression {
    253 public:
    254    ast_expression_bin(int oper, ast_expression *, ast_expression *);
    255 
    256    virtual void print(void) const;
    257 };
    258 
    259 /**
    260  * Subclass of expressions for function calls
    261  */
    262 class ast_function_expression : public ast_expression {
    263 public:
    264    ast_function_expression(ast_expression *callee)
    265       : ast_expression(ast_function_call, callee,
    266 		       NULL, NULL),
    267 	cons(false)
    268    {
    269       /* empty */
    270    }
    271 
    272    ast_function_expression(class ast_type_specifier *type)
    273       : ast_expression(ast_function_call, (ast_expression *) type,
    274 		       NULL, NULL),
    275 	cons(true)
    276    {
    277       /* empty */
    278    }
    279 
    280    bool is_constructor() const
    281    {
    282       return cons;
    283    }
    284 
    285    virtual ir_rvalue *hir(exec_list *instructions,
    286 			  struct _mesa_glsl_parse_state *state);
    287 
    288 private:
    289    /**
    290     * Is this function call actually a constructor?
    291     */
    292    bool cons;
    293 };
    294 
    295 
    296 /**
    297  * Number of possible operators for an ast_expression
    298  *
    299  * This is done as a define instead of as an additional value in the enum so
    300  * that the compiler won't generate spurious messages like "warning:
    301  * enumeration value ast_num_operators not handled in switch"
    302  */
    303 #define AST_NUM_OPERATORS (ast_sequence + 1)
    304 
    305 
    306 class ast_compound_statement : public ast_node {
    307 public:
    308    ast_compound_statement(int new_scope, ast_node *statements);
    309    virtual void print(void) const;
    310 
    311    virtual ir_rvalue *hir(exec_list *instructions,
    312 			  struct _mesa_glsl_parse_state *state);
    313 
    314    int new_scope;
    315    exec_list statements;
    316 };
    317 
    318 class ast_declaration : public ast_node {
    319 public:
    320    ast_declaration(const char *identifier, int is_array, ast_expression *array_size,
    321 		   ast_expression *initializer);
    322    virtual void print(void) const;
    323 
    324    const char *identifier;
    325 
    326    int is_array;
    327    ast_expression *array_size;
    328 
    329    ast_expression *initializer;
    330 };
    331 
    332 
    333 enum {
    334    ast_precision_none = 0, /**< Absence of precision qualifier. */
    335    ast_precision_high,
    336    ast_precision_medium,
    337    ast_precision_low
    338 };
    339 
    340 struct ast_type_qualifier {
    341    /* Callers of this ralloc-based new need not call delete. It's
    342     * easier to just ralloc_free 'ctx' (or any of its ancestors). */
    343    static void* operator new(size_t size, void *ctx)
    344    {
    345       void *node;
    346 
    347       node = rzalloc_size(ctx, size);
    348       assert(node != NULL);
    349 
    350       return node;
    351    }
    352 
    353    /* If the user *does* call delete, that's OK, we will just
    354     * ralloc_free in that case. */
    355    static void operator delete(void *table)
    356    {
    357       ralloc_free(table);
    358    }
    359 
    360    union {
    361       struct {
    362 	 unsigned invariant:1;
    363 	 unsigned constant:1;
    364 	 unsigned attribute:1;
    365 	 unsigned varying:1;
    366 	 unsigned in:1;
    367 	 unsigned out:1;
    368 	 unsigned centroid:1;
    369 	 unsigned uniform:1;
    370 	 unsigned smooth:1;
    371 	 unsigned flat:1;
    372 	 unsigned noperspective:1;
    373 
    374 	 /** \name Layout qualifiers for GL_ARB_fragment_coord_conventions */
    375 	 /*@{*/
    376 	 unsigned origin_upper_left:1;
    377 	 unsigned pixel_center_integer:1;
    378 	 /*@}*/
    379 
    380 	 /**
    381 	  * Flag set if GL_ARB_explicit_attrib_location "location" layout
    382 	  * qualifier is used.
    383 	  */
    384 	 unsigned explicit_location:1;
    385 	 /**
    386 	  * Flag set if GL_ARB_explicit_attrib_location "index" layout
    387 	  * qualifier is used.
    388 	  */
    389 	 unsigned explicit_index:1;
    390 
    391          /** \name Layout qualifiers for GL_AMD_conservative_depth */
    392          /** \{ */
    393          unsigned depth_any:1;
    394          unsigned depth_greater:1;
    395          unsigned depth_less:1;
    396          unsigned depth_unchanged:1;
    397          /** \} */
    398 
    399 	 /** \name Layout qualifiers for GL_ARB_uniform_buffer_object */
    400 	 /** \{ */
    401          unsigned std140:1;
    402          unsigned shared:1;
    403          unsigned packed:1;
    404          unsigned column_major:1;
    405          unsigned row_major:1;
    406 	 /** \} */
    407       }
    408       /** \brief Set of flags, accessed by name. */
    409       q;
    410 
    411       /** \brief Set of flags, accessed as a bitmask. */
    412       unsigned i;
    413    } flags;
    414 
    415    /**
    416     * Location specified via GL_ARB_explicit_attrib_location layout
    417     *
    418     * \note
    419     * This field is only valid if \c explicit_location is set.
    420     */
    421    int location;
    422    /**
    423     * Index specified via GL_ARB_explicit_attrib_location layout
    424     *
    425     * \note
    426     * This field is only valid if \c explicit_index is set.
    427     */
    428    int index;
    429 
    430    /**
    431     * Return true if and only if an interpolation qualifier is present.
    432     */
    433    bool has_interpolation() const;
    434 
    435    /**
    436     * \brief Return string representation of interpolation qualifier.
    437     *
    438     * If an interpolation qualifier is present, then return that qualifier's
    439     * string representation. Otherwise, return null. For example, if the
    440     * noperspective bit is set, then this returns "noperspective".
    441     *
    442     * If multiple interpolation qualifiers are somehow present, then the
    443     * returned string is undefined but not null.
    444     */
    445    const char *interpolation_string() const;
    446 
    447    bool merge_qualifier(YYLTYPE *loc,
    448 			_mesa_glsl_parse_state *state,
    449 			ast_type_qualifier q);
    450 };
    451 
    452 class ast_declarator_list;
    453 
    454 class ast_struct_specifier : public ast_node {
    455 public:
    456    ast_struct_specifier(const char *identifier,
    457 			ast_declarator_list *declarator_list);
    458    virtual void print(void) const;
    459 
    460    virtual ir_rvalue *hir(exec_list *instructions,
    461 			  struct _mesa_glsl_parse_state *state);
    462 
    463    const char *name;
    464    /* List of ast_declarator_list * */
    465    exec_list declarations;
    466 };
    467 
    468 
    469 
    470 class ast_type_specifier : public ast_node {
    471 public:
    472    /** Construct a type specifier from a type name */
    473    ast_type_specifier(const char *name)
    474       : type_name(name), structure(NULL),
    475 	is_array(false), array_size(NULL), precision(ast_precision_none),
    476 	is_precision_statement(false)
    477    {
    478       /* empty */
    479    }
    480 
    481    /** Construct a type specifier from a structure definition */
    482    ast_type_specifier(ast_struct_specifier *s)
    483       : type_name(s->name), structure(s),
    484 	is_array(false), array_size(NULL), precision(ast_precision_none),
    485 	is_precision_statement(false)
    486    {
    487       /* empty */
    488    }
    489 
    490    const struct glsl_type *glsl_type(const char **name,
    491 				     struct _mesa_glsl_parse_state *state)
    492       const;
    493 
    494    virtual void print(void) const;
    495 
    496    ir_rvalue *hir(exec_list *, struct _mesa_glsl_parse_state *);
    497 
    498    const char *type_name;
    499    ast_struct_specifier *structure;
    500 
    501    int is_array;
    502    ast_expression *array_size;
    503 
    504    unsigned precision:2;
    505 
    506    bool is_precision_statement;
    507 };
    508 
    509 
    510 class ast_fully_specified_type : public ast_node {
    511 public:
    512    virtual void print(void) const;
    513    bool has_qualifiers() const;
    514 
    515    ast_type_qualifier qualifier;
    516    ast_type_specifier *specifier;
    517 };
    518 
    519 
    520 class ast_declarator_list : public ast_node {
    521 public:
    522    ast_declarator_list(ast_fully_specified_type *);
    523    virtual void print(void) const;
    524 
    525    virtual ir_rvalue *hir(exec_list *instructions,
    526 			  struct _mesa_glsl_parse_state *state);
    527 
    528    ast_fully_specified_type *type;
    529    exec_list declarations;
    530 
    531    /**
    532     * Special flag for vertex shader "invariant" declarations.
    533     *
    534     * Vertex shaders can contain "invariant" variable redeclarations that do
    535     * not include a type.  For example, "invariant gl_Position;".  This flag
    536     * is used to note these cases when no type is specified.
    537     */
    538    int invariant;
    539 
    540    /**
    541     * Flag indicating that these declarators are in a uniform block,
    542     * allowing UBO type qualifiers.
    543     */
    544    bool ubo_qualifiers_valid;
    545 };
    546 
    547 
    548 class ast_parameter_declarator : public ast_node {
    549 public:
    550    ast_parameter_declarator()
    551    {
    552       this->identifier = NULL;
    553       this->is_array = false;
    554       this->array_size = 0;
    555    }
    556 
    557    virtual void print(void) const;
    558 
    559    virtual ir_rvalue *hir(exec_list *instructions,
    560 			  struct _mesa_glsl_parse_state *state);
    561 
    562    ast_fully_specified_type *type;
    563    const char *identifier;
    564    int is_array;
    565    ast_expression *array_size;
    566 
    567    static void parameters_to_hir(exec_list *ast_parameters,
    568 				 bool formal, exec_list *ir_parameters,
    569 				 struct _mesa_glsl_parse_state *state);
    570 
    571 private:
    572    /** Is this parameter declaration part of a formal parameter list? */
    573    bool formal_parameter;
    574 
    575    /**
    576     * Is this parameter 'void' type?
    577     *
    578     * This field is set by \c ::hir.
    579     */
    580    bool is_void;
    581 };
    582 
    583 
    584 class ast_function : public ast_node {
    585 public:
    586    ast_function(void);
    587 
    588    virtual void print(void) const;
    589 
    590    virtual ir_rvalue *hir(exec_list *instructions,
    591 			  struct _mesa_glsl_parse_state *state);
    592 
    593    ast_fully_specified_type *return_type;
    594    const char *identifier;
    595 
    596    exec_list parameters;
    597 
    598 private:
    599    /**
    600     * Is this prototype part of the function definition?
    601     *
    602     * Used by ast_function_definition::hir to process the parameters, etc.
    603     * of the function.
    604     *
    605     * \sa ::hir
    606     */
    607    bool is_definition;
    608 
    609    /**
    610     * Function signature corresponding to this function prototype instance
    611     *
    612     * Used by ast_function_definition::hir to process the parameters, etc.
    613     * of the function.
    614     *
    615     * \sa ::hir
    616     */
    617    class ir_function_signature *signature;
    618 
    619    friend class ast_function_definition;
    620 };
    621 
    622 
    623 class ast_expression_statement : public ast_node {
    624 public:
    625    ast_expression_statement(ast_expression *);
    626    virtual void print(void) const;
    627 
    628    virtual ir_rvalue *hir(exec_list *instructions,
    629 			  struct _mesa_glsl_parse_state *state);
    630 
    631    ast_expression *expression;
    632 };
    633 
    634 
    635 class ast_case_label : public ast_node {
    636 public:
    637    ast_case_label(ast_expression *test_value);
    638    virtual void print(void) const;
    639 
    640    virtual ir_rvalue *hir(exec_list *instructions,
    641 			  struct _mesa_glsl_parse_state *state);
    642 
    643    /**
    644     * An test value of NULL means 'default'.
    645     */
    646    ast_expression *test_value;
    647 };
    648 
    649 
    650 class ast_case_label_list : public ast_node {
    651 public:
    652    ast_case_label_list(void);
    653    virtual void print(void) const;
    654 
    655    virtual ir_rvalue *hir(exec_list *instructions,
    656 			  struct _mesa_glsl_parse_state *state);
    657 
    658    /**
    659     * A list of case labels.
    660     */
    661    exec_list labels;
    662 };
    663 
    664 
    665 class ast_case_statement : public ast_node {
    666 public:
    667    ast_case_statement(ast_case_label_list *labels);
    668    virtual void print(void) const;
    669 
    670    virtual ir_rvalue *hir(exec_list *instructions,
    671 			  struct _mesa_glsl_parse_state *state);
    672 
    673    ast_case_label_list *labels;
    674 
    675    /**
    676     * A list of statements.
    677     */
    678    exec_list stmts;
    679 };
    680 
    681 
    682 class ast_case_statement_list : public ast_node {
    683 public:
    684    ast_case_statement_list(void);
    685    virtual void print(void) const;
    686 
    687    virtual ir_rvalue *hir(exec_list *instructions,
    688 			  struct _mesa_glsl_parse_state *state);
    689 
    690    /**
    691     * A list of cases.
    692     */
    693    exec_list cases;
    694 };
    695 
    696 
    697 class ast_switch_body : public ast_node {
    698 public:
    699    ast_switch_body(ast_case_statement_list *stmts);
    700    virtual void print(void) const;
    701 
    702    virtual ir_rvalue *hir(exec_list *instructions,
    703 			  struct _mesa_glsl_parse_state *state);
    704 
    705    ast_case_statement_list *stmts;
    706 };
    707 
    708 
    709 class ast_selection_statement : public ast_node {
    710 public:
    711    ast_selection_statement(ast_expression *condition,
    712 			   ast_node *then_statement,
    713 			   ast_node *else_statement);
    714    virtual void print(void) const;
    715 
    716    virtual ir_rvalue *hir(exec_list *instructions,
    717 			  struct _mesa_glsl_parse_state *state);
    718 
    719    ast_expression *condition;
    720    ast_node *then_statement;
    721    ast_node *else_statement;
    722 };
    723 
    724 
    725 class ast_switch_statement : public ast_node {
    726 public:
    727    ast_switch_statement(ast_expression *test_expression,
    728 			ast_node *body);
    729    virtual void print(void) const;
    730 
    731    virtual ir_rvalue *hir(exec_list *instructions,
    732 			  struct _mesa_glsl_parse_state *state);
    733 
    734    ast_expression *test_expression;
    735    ast_node *body;
    736 
    737 protected:
    738    void test_to_hir(exec_list *, struct _mesa_glsl_parse_state *);
    739 };
    740 
    741 class ast_iteration_statement : public ast_node {
    742 public:
    743    ast_iteration_statement(int mode, ast_node *init, ast_node *condition,
    744 			   ast_expression *rest_expression, ast_node *body);
    745 
    746    virtual void print(void) const;
    747 
    748    virtual ir_rvalue *hir(exec_list *, struct _mesa_glsl_parse_state *);
    749 
    750    enum ast_iteration_modes {
    751       ast_for,
    752       ast_while,
    753       ast_do_while
    754    } mode;
    755 
    756 
    757    ast_node *init_statement;
    758    ast_node *condition;
    759    ast_expression *rest_expression;
    760 
    761    ast_node *body;
    762 
    763 private:
    764    /**
    765     * Generate IR from the condition of a loop
    766     *
    767     * This is factored out of ::hir because some loops have the condition
    768     * test at the top (for and while), and others have it at the end (do-while).
    769     */
    770    void condition_to_hir(class ir_loop *, struct _mesa_glsl_parse_state *);
    771 };
    772 
    773 
    774 class ast_jump_statement : public ast_node {
    775 public:
    776    ast_jump_statement(int mode, ast_expression *return_value);
    777    virtual void print(void) const;
    778 
    779    virtual ir_rvalue *hir(exec_list *instructions,
    780 			  struct _mesa_glsl_parse_state *state);
    781 
    782    enum ast_jump_modes {
    783       ast_continue,
    784       ast_break,
    785       ast_return,
    786       ast_discard
    787    } mode;
    788 
    789    ast_expression *opt_return_value;
    790 };
    791 
    792 
    793 class ast_function_definition : public ast_node {
    794 public:
    795    virtual void print(void) const;
    796 
    797    virtual ir_rvalue *hir(exec_list *instructions,
    798 			  struct _mesa_glsl_parse_state *state);
    799 
    800    ast_function *prototype;
    801    ast_compound_statement *body;
    802 };
    803 
    804 class ast_uniform_block : public ast_node {
    805 public:
    806    ast_uniform_block(ast_type_qualifier layout,
    807 		     const char *block_name,
    808 		     ast_declarator_list *member_list)
    809    : layout(layout), block_name(block_name)
    810    {
    811       declarations.push_degenerate_list_at_head(&member_list->link);
    812    }
    813 
    814    virtual ir_rvalue *hir(exec_list *instructions,
    815 			  struct _mesa_glsl_parse_state *state);
    816 
    817    ast_type_qualifier layout;
    818    const char *block_name;
    819    /** List of ast_declarator_list * */
    820    exec_list declarations;
    821 };
    822 /*@}*/
    823 
    824 extern void
    825 _mesa_ast_to_hir(exec_list *instructions, struct _mesa_glsl_parse_state *state);
    826 
    827 extern ir_rvalue *
    828 _mesa_ast_field_selection_to_hir(const ast_expression *expr,
    829 				 exec_list *instructions,
    830 				 struct _mesa_glsl_parse_state *state);
    831 
    832 void
    833 emit_function(_mesa_glsl_parse_state *state, ir_function *f);
    834 
    835 #endif /* AST_H */
    836