slang_shader.syn

来自「Mesa is an open-source implementation of」· SYN 代码 · 共 1,616 行 · 第 1/5 页

/*
 * Mesa 3-D graphics library
 * Version:  6.5
 *
 * Copyright (C) 2004-2006  Brian Paul   All Rights Reserved.
 *
 * 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 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
 * BRIAN PAUL 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.
 */

/*
 * \file slang_shader.syn
 * slang vertex/fragment shader syntax
 * \author Michal Krol
 */

/*
 * usage:
 *   syn2c slang_shader.syn > slang_shader_syn.h
 *
 * when modifying or extending this file, several things must be taken into consideration:
 * - when adding new operators that were marked as reserved in the initial specification,
 *   one must only uncomment particular lines of code that refer to operators being added;
 * - when adding new shader target, one must reserve new value for shader_type register and
 *   use it in .if constructs for symbols that are exclusive for that shader;
 * - some symbols mimic output of other symbols - the best example is the "for" construct:
 *   expression "for (foo(); ; bar())" is seen as "for (foo(); true; bar())" by the output
 *   processor - hence, special care must be taken when rearranging output of essential symbols;
 * - order of single-quoted tokens does matter in alternatives - so do not parse "<" operator
 *   before "<<" and "<<" before "<<=";
 * - all double-quoted tokens are internally preprocessed to eliminate problems with parsing
 *   strings that are prefixes of other strings, like "sampler1D" and "sampler1DShadow";
 */

.syntax translation_unit;

/* revision number - increment after each change affecting emitted output */
.emtcode REVISION                                   4

/* external declaration (or precision or invariant stmt) */
.emtcode EXTERNAL_NULL                              0
.emtcode EXTERNAL_FUNCTION_DEFINITION               1
.emtcode EXTERNAL_DECLARATION                       2
.emtcode DEFAULT_PRECISION                          3
.emtcode INVARIANT_STMT                             4

/* precision */
.emtcode PRECISION_DEFAULT                          0
.emtcode PRECISION_LOW                              1
.emtcode PRECISION_MEDIUM                           2
.emtcode PRECISION_HIGH                             3

/* declaration */
.emtcode DECLARATION_FUNCTION_PROTOTYPE             1
.emtcode DECLARATION_INIT_DECLARATOR_LIST           2

/* function type */
.emtcode FUNCTION_ORDINARY                          0
.emtcode FUNCTION_CONSTRUCTOR                       1
.emtcode FUNCTION_OPERATOR                          2

/* operator type */
.emtcode OPERATOR_ADDASSIGN                         1
.emtcode OPERATOR_SUBASSIGN                         2
.emtcode OPERATOR_MULASSIGN                         3
.emtcode OPERATOR_DIVASSIGN                         4
/*.emtcode OPERATOR_MODASSIGN                         5*/
/*.emtcode OPERATOR_LSHASSIGN                         6*/
/*.emtcode OPERATOR_RSHASSIGN                         7*/
/*.emtcode OPERATOR_ORASSIGN                          8*/
/*.emtcode OPERATOR_XORASSIGN                         9*/
/*.emtcode OPERATOR_ANDASSIGN                         10*/
.emtcode OPERATOR_LOGICALXOR                        11
/*.emtcode OPERATOR_BITOR                             12*/
/*.emtcode OPERATOR_BITXOR                            13*/
/*.emtcode OPERATOR_BITAND                            14*/
.emtcode OPERATOR_LESS                              15
.emtcode OPERATOR_GREATER                           16
.emtcode OPERATOR_LESSEQUAL                         17
.emtcode OPERATOR_GREATEREQUAL                      18
/*.emtcode OPERATOR_LSHIFT                            19*/
/*.emtcode OPERATOR_RSHIFT                            20*/
.emtcode OPERATOR_MULTIPLY                          21
.emtcode OPERATOR_DIVIDE                            22
/*.emtcode OPERATOR_MODULUS                           23*/
.emtcode OPERATOR_INCREMENT                         24
.emtcode OPERATOR_DECREMENT                         25
.emtcode OPERATOR_PLUS                              26
.emtcode OPERATOR_MINUS                             27
/*.emtcode OPERATOR_COMPLEMENT                        28*/
.emtcode OPERATOR_NOT                               29

/* init declarator list */
.emtcode DECLARATOR_NONE                            0
.emtcode DECLARATOR_NEXT                            1

/* variable declaration */
.emtcode VARIABLE_NONE                              0
.emtcode VARIABLE_IDENTIFIER                        1
.emtcode VARIABLE_INITIALIZER                       2
.emtcode VARIABLE_ARRAY_EXPLICIT                    3
.emtcode VARIABLE_ARRAY_UNKNOWN                     4

/* type qualifier */
.emtcode TYPE_QUALIFIER_NONE                        0
.emtcode TYPE_QUALIFIER_CONST                       1
.emtcode TYPE_QUALIFIER_ATTRIBUTE                   2
.emtcode TYPE_QUALIFIER_VARYING                     3
.emtcode TYPE_QUALIFIER_UNIFORM                     4
.emtcode TYPE_QUALIFIER_FIXEDOUTPUT                 5
.emtcode TYPE_QUALIFIER_FIXEDINPUT                  6

/* type specifier */
.emtcode TYPE_SPECIFIER_VOID                        0
.emtcode TYPE_SPECIFIER_BOOL                        1
.emtcode TYPE_SPECIFIER_BVEC2                       2
.emtcode TYPE_SPECIFIER_BVEC3                       3
.emtcode TYPE_SPECIFIER_BVEC4                       4
.emtcode TYPE_SPECIFIER_INT                         5
.emtcode TYPE_SPECIFIER_IVEC2                       6
.emtcode TYPE_SPECIFIER_IVEC3                       7
.emtcode TYPE_SPECIFIER_IVEC4                       8
.emtcode TYPE_SPECIFIER_FLOAT                       9
.emtcode TYPE_SPECIFIER_VEC2                        10
.emtcode TYPE_SPECIFIER_VEC3                        11
.emtcode TYPE_SPECIFIER_VEC4                        12
.emtcode TYPE_SPECIFIER_MAT2                        13
.emtcode TYPE_SPECIFIER_MAT3                        14
.emtcode TYPE_SPECIFIER_MAT4                        15
.emtcode TYPE_SPECIFIER_SAMPLER1D                   16
.emtcode TYPE_SPECIFIER_SAMPLER2D                   17
.emtcode TYPE_SPECIFIER_SAMPLER3D                   18
.emtcode TYPE_SPECIFIER_SAMPLERCUBE                 19
.emtcode TYPE_SPECIFIER_SAMPLER1DSHADOW             20
.emtcode TYPE_SPECIFIER_SAMPLER2DSHADOW             21
.emtcode TYPE_SPECIFIER_SAMPLER2DRECT               22
.emtcode TYPE_SPECIFIER_SAMPLER2DRECTSHADOW         23
.emtcode TYPE_SPECIFIER_STRUCT                      24
.emtcode TYPE_SPECIFIER_TYPENAME                    25

/* OpenGL 2.1 */
.emtcode TYPE_SPECIFIER_MAT23                       26
.emtcode TYPE_SPECIFIER_MAT32                       27
.emtcode TYPE_SPECIFIER_MAT24                       28
.emtcode TYPE_SPECIFIER_MAT42                       29
.emtcode TYPE_SPECIFIER_MAT34                       30
.emtcode TYPE_SPECIFIER_MAT43                       31


/* structure field */
.emtcode FIELD_NONE                                 0
.emtcode FIELD_NEXT                                 1
.emtcode FIELD_ARRAY                                2

/* operation */
.emtcode OP_END                                     0
.emtcode OP_BLOCK_BEGIN_NO_NEW_SCOPE                1
.emtcode OP_BLOCK_BEGIN_NEW_SCOPE                   2
.emtcode OP_DECLARE                                 3
.emtcode OP_ASM                                     4
.emtcode OP_BREAK                                   5
.emtcode OP_CONTINUE                                6
.emtcode OP_DISCARD                                 7
.emtcode OP_RETURN                                  8
.emtcode OP_EXPRESSION                              9
.emtcode OP_IF                                      10
.emtcode OP_WHILE                                   11
.emtcode OP_DO                                      12
.emtcode OP_FOR                                     13
.emtcode OP_PUSH_VOID                               14
.emtcode OP_PUSH_BOOL                               15
.emtcode OP_PUSH_INT                                16
.emtcode OP_PUSH_FLOAT                              17
.emtcode OP_PUSH_IDENTIFIER                         18
.emtcode OP_SEQUENCE                                19
.emtcode OP_ASSIGN                                  20
.emtcode OP_ADDASSIGN                               21
.emtcode OP_SUBASSIGN                               22
.emtcode OP_MULASSIGN                               23
.emtcode OP_DIVASSIGN                               24
/*.emtcode OP_MODASSIGN                               25*/
/*.emtcode OP_LSHASSIGN                               26*/
/*.emtcode OP_RSHASSIGN                               27*/
/*.emtcode OP_ORASSIGN                                28*/
/*.emtcode OP_XORASSIGN                               29*/
/*.emtcode OP_ANDASSIGN                               30*/
.emtcode OP_SELECT                                  31
.emtcode OP_LOGICALOR                               32
.emtcode OP_LOGICALXOR                              33
.emtcode OP_LOGICALAND                              34
/*.emtcode OP_BITOR                                   35*/
/*.emtcode OP_BITXOR                                  36*/
/*.emtcode OP_BITAND                                  37*/
.emtcode OP_EQUAL                                   38
.emtcode OP_NOTEQUAL                                39
.emtcode OP_LESS                                    40
.emtcode OP_GREATER                                 41
.emtcode OP_LESSEQUAL                               42
.emtcode OP_GREATEREQUAL                            43
/*.emtcode OP_LSHIFT                                  44*/
/*.emtcode OP_RSHIFT                                  45*/
.emtcode OP_ADD                                     46
.emtcode OP_SUBTRACT                                47
.emtcode OP_MULTIPLY                                48
.emtcode OP_DIVIDE                                  49
/*.emtcode OP_MODULUS                                 50*/
.emtcode OP_PREINCREMENT                            51
.emtcode OP_PREDECREMENT                            52
.emtcode OP_PLUS                                    53
.emtcode OP_MINUS                                   54
/*.emtcode OP_COMPLEMENT                              55*/
.emtcode OP_NOT                                     56
.emtcode OP_SUBSCRIPT                               57
.emtcode OP_CALL                                    58
.emtcode OP_FIELD                                   59
.emtcode OP_POSTINCREMENT                           60
.emtcode OP_POSTDECREMENT                           61

/* parameter qualifier */
.emtcode PARAM_QUALIFIER_IN                         0
.emtcode PARAM_QUALIFIER_OUT                        1
.emtcode PARAM_QUALIFIER_INOUT                      2

/* function parameter */
.emtcode PARAMETER_NONE                             0
.emtcode PARAMETER_NEXT                             1

/* function parameter array presence */
.emtcode PARAMETER_ARRAY_NOT_PRESENT                0
.emtcode PARAMETER_ARRAY_PRESENT                    1

/* INVALID_EXTERNAL_DECLARATION seems to be reported when there's */
/* any syntax errors... */
.errtext INVALID_EXTERNAL_DECLARATION               "2001: Syntax error."
.errtext INVALID_OPERATOR_OVERRIDE                  "2002: Invalid operator override."
.errtext LBRACE_EXPECTED                            "2003: '{' expected but '$err_token$' found."
.errtext LPAREN_EXPECTED                            "2004: '(' expected but '$err_token$' found."
.errtext RPAREN_EXPECTED                            "2005: ')' expected but '$err_token$' found."
.errtext INVALID_PRECISION                          "2006: Invalid precision specifier '$err_token$'."
.errtext INVALID_PRECISION_TYPE                     "2007: Invalid precision type '$err_token$'."


/* tells whether the shader that is being parsed is a built-in shader or not */
/*   0 - normal behaviour */
/*   1 - accepts constructor and operator definitions and __asm statements */
/* the implementation will set it to 1 when compiling internal built-in shaders */
.regbyte parsing_builtin                            0

/* holds the type of the shader being parsed; possible values are listed below */
/*   FRAGMENT_SHADER            1 */
/*   VERTEX_SHADER              2 */
/* shader type is set by the caller before parsing */
.regbyte shader_type                                0

/*
    <variable_identifier>               ::= <identifier>
*/
variable_identifier
    identifier .emit OP_PUSH_IDENTIFIER;

/*
    <primary_expression>                ::= <variable_identifier>
                                          | <intconstant>
                                          | <floatconstant>
                                          | <boolconstant>
                                          | "(" <expression> ")"
*/
primary_expression
    floatconstant .or boolconstant .or intconstant .or variable_identifier .or primary_expression_1;
primary_expression_1
    lparen .and expression .and rparen;

/*
    <postfix_expression>                ::= <primary_expression>
                                          | <postfix_expression> "[" <integer_expression> "]"
                                          | <function_call>
                                          | <postfix_expression> "." <field_selection>
                                          | <postfix_expression> "++"
                                          | <postfix_expression> "--"
*/
postfix_expression
    postfix_expression_1 .and .loop postfix_expression_2;
postfix_expression_1
    function_call .or primary_expression;
postfix_expression_2
    postfix_expression_3 .or postfix_expression_4 .or
    plusplus .emit OP_POSTINCREMENT .or
    minusminus .emit OP_POSTDECREMENT;
postfix_expression_3
    lbracket .and integer_expression .and rbracket .emit OP_SUBSCRIPT;
postfix_expression_4
    dot .and field_selection .emit OP_FIELD;

/*
    <integer_expression>                ::= <expression>
*/
integer_expression
    expression;

/*
    <function_call>                     ::= <function_call_generic>
*/
function_call
    function_call_generic .emit OP_CALL .and .true .emit OP_END;

/*
    <function_call_generic>             ::= <function_call_header_with_parameters> ")"
                                          | <function_call_header_no_parameters> ")"
*/
function_call_generic