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mojoshader_parser_hlsl.lemon
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mojoshader_parser_hlsl.lemon
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/**
* MojoShader; generate shader programs from bytecode of compiled
* Direct3D shaders.
*
* Please see the file LICENSE.txt in the source's root directory.
*
* This file written by Ryan C. Gordon.
*/
// This is a Lemon Parser grammar for HLSL. It is based on an ANSI C YACC
// grammar by Jeff Lee: http://www.lysator.liu.se/c/ANSI-C-grammar-y.html
// Lemon is here: http://www.hwaci.com/sw/lemon/ ... the source is included
// with MojoShader, and built with the library, so you don't have to track
// down the dependency.
// HLSL syntax is described, informally, here:
// http://msdn.microsoft.com/en-us/library/bb509615(VS.85).aspx
%name ParseHLSL
%start_symbol shader
%token_prefix TOKEN_HLSL_
%token_type { TokenData }
%extra_argument { Context *ctx }
%include {
#ifndef __MOJOSHADER_HLSL_COMPILER__
#error Do not compile this file directly.
#endif
}
%parse_failure {
fprintf(stderr,"Giving up. Parser is hopelessly lost...\n");
}
%stack_overflow {
fprintf(stderr,"Giving up. Parser stack overflow\n");
}
// operator precedence (matches C spec)...
%left COMMA.
%right ASSIGN ADDASSIGN SUBASSIGN MULASSIGN DIVASSIGN MODASSIGN LSHIFTASSIGN
RSHIFTASSIGN ANDASSIGN ORASSIGN XORASSIGN.
%right QUESTION.
%left OROR.
%left ANDAND.
%left OR.
%left XOR.
%left AND.
%left EQL NEQ.
%left LT LEQ GT GEQ.
%left LSHIFT RSHIFT.
%left PLUS MINUS.
%left STAR SLASH PERCENT.
%right TYPECAST EXCLAMATION COMPLEMENT MINUSMINUS PLUSPLUS.
%left DOT LBRACKET RBRACKET LPAREN RPAREN.
// bump up the precedence of ELSE, to avoid shift/reduce conflict on the
// usual "dangling else ambiguity" ...
%right ELSE.
// The rules...
shader ::= compilation_units.
compilation_units ::= compilation_unit.
compilation_units ::= compilation_units compilation_unit.
compilation_unit ::= function_declaration.
compilation_unit ::= function_definition.
compilation_unit ::= global_variable.
compilation_unit ::= typedef_statement.
compilation_unit ::= struct_statement.
function_declaration ::= function_signature SEMICOLON.
function_definition ::= function_signature statement_block.
function_signature ::= function_storageclass function_details semantic.
function_signature ::= function_storageclass function_details.
function_signature ::= function_details semantic.
function_signature ::= function_details.
function_details ::= datatype identifier LPAREN function_arguments RPAREN.
// !!! FIXME: there is a "target" storage class that is the name of the
// !!! FIXME: platform that this function is meant for...but I don't know
// !!! FIXME: what tokens are valid here.
// !!! FIXME: Also, the docs say "one of" inline or target, but I bet you can
// !!! FIXME: specify both.
//function_storageclass ::= target.
function_storageclass ::= INLINE.
function_arguments ::= VOID.
function_arguments ::= function_argument_list.
function_arguments ::= .
function_argument_list ::= function_argument.
function_argument_list ::= function_argument_list COMMA function_argument.
function_argument ::= input_modifier datatype identifier semantic interpolation_mod initializer.
function_argument ::= input_modifier datatype identifier semantic interpolation_mod.
function_argument ::= input_modifier datatype identifier semantic initializer.
function_argument ::= input_modifier datatype identifier semantic.
function_argument ::= input_modifier datatype identifier interpolation_mod initializer.
function_argument ::= input_modifier datatype identifier interpolation_mod.
function_argument ::= input_modifier datatype identifier initializer.
function_argument ::= input_modifier datatype identifier.
function_argument ::= datatype identifier semantic interpolation_mod initializer.
function_argument ::= datatype identifier semantic interpolation_mod.
function_argument ::= datatype identifier semantic initializer.
function_argument ::= datatype identifier semantic.
function_argument ::= datatype identifier interpolation_mod initializer.
function_argument ::= datatype identifier interpolation_mod.
function_argument ::= datatype identifier initializer.
function_argument ::= datatype identifier.
input_modifier ::= IN.
input_modifier ::= INOUT.
input_modifier ::= OUT.
input_modifier ::= UNIFORM.
semantic ::= COLON SEMANTIC.
// DX10 only?
interpolation_mod ::= LINEAR.
interpolation_mod ::= CENTROID.
interpolation_mod ::= NOINTERPOLATION.
interpolation_mod ::= NOPERSPECTIVE.
interpolation_mod ::= SAMPLE.
global_variable ::= variable_declaration.
variable_declaration ::= variable_attribute_list datatype variable_declaration_details_list SEMICOLON.
variable_declaration ::= datatype variable_declaration_details_list SEMICOLON.
variable_declaration ::= struct_declaration scalar_or_array SEMICOLON.
variable_declaration_details_list ::= variable_declaration_details.
variable_declaration_details_list ::= variable_declaration_details_list COMMA variable_declaration_details.
variable_declaration_details ::= scalar_or_array semantic annotations initializer variable_lowlevel.
variable_declaration_details ::= scalar_or_array semantic annotations initializer.
variable_declaration_details ::= scalar_or_array semantic annotations variable_lowlevel.
variable_declaration_details ::= scalar_or_array semantic annotations.
variable_declaration_details ::= scalar_or_array semantic initializer variable_lowlevel.
variable_declaration_details ::= scalar_or_array semantic initializer.
variable_declaration_details ::= scalar_or_array semantic variable_lowlevel.
variable_declaration_details ::= scalar_or_array semantic.
variable_declaration_details ::= scalar_or_array annotations initializer variable_lowlevel.
variable_declaration_details ::= scalar_or_array annotations initializer.
variable_declaration_details ::= scalar_or_array annotations variable_lowlevel.
variable_declaration_details ::= scalar_or_array annotations.
variable_declaration_details ::= scalar_or_array initializer variable_lowlevel.
variable_declaration_details ::= scalar_or_array initializer.
variable_declaration_details ::= scalar_or_array variable_lowlevel.
variable_declaration_details ::= scalar_or_array.
// !!! FIXME: we don't handle full sampler declarations at the moment.
struct_declaration ::= STRUCT identifier(A) LBRACE struct_member_list RBRACE.
{
add_usertype(ctx, A.token, A.tokenlen);
}
struct_member_list ::= struct_member.
struct_member_list ::= struct_member_list struct_member.
struct_member ::= interpolation_mod struct_member_details.
struct_member ::= struct_member_details.
struct_member_details ::= datatype struct_member_item_list SEMICOLON.
struct_member_item_list ::= scalar_or_array.
struct_member_item_list ::= struct_member_item_list COMMA identifier.
typedef_statement ::= TYPEDEF CONST datatype scalar_or_array.
typedef_statement ::= TYPEDEF datatype scalar_or_array.
variable_lowlevel ::= packoffset register.
variable_lowlevel ::= packoffset.
variable_lowlevel ::= register.
scalar_or_array ::= identifier LBRACKET INT_CONSTANT RBRACKET.
scalar_or_array ::= identifier.
packoffset ::= PACKOFFSET LPAREN identifier identifier RPAREN.
packoffset ::= PACKOFFSET LPAREN identifier RPAREN.
register ::= COLON REGISTER LPAREN identifier RPAREN.
annotations ::= LT annotation_list GT.
annotation_list ::= annotation.
annotation_list ::= annotation_list annotation.
annotation ::= datatype_scalar initializer SEMICOLON.
variable_attribute_list ::= variable_attribute.
variable_attribute_list ::= variable_attribute_list variable_attribute.
variable_attribute ::= EXTERN.
variable_attribute ::= NOINTERPOLATION.
variable_attribute ::= SHARED.
variable_attribute ::= STATIC.
variable_attribute ::= UNIFORM.
variable_attribute ::= VOLATILE.
variable_attribute ::= CONST.
variable_attribute ::= ROWMAJOR.
variable_attribute ::= COLUMNMAJOR.
initializer ::= ASSIGN expression.
intrinsic_datatype ::= datatype_vector.
intrinsic_datatype ::= datatype_matrix.
intrinsic_datatype ::= datatype_scalar.
intrinsic_datatype ::= datatype_sampler.
datatype ::= intrinsic_datatype.
datatype ::= USERTYPE.
datatype_sampler ::= SAMPLER.
datatype_sampler ::= SAMPLER1D.
datatype_sampler ::= SAMPLER2D.
datatype_sampler ::= SAMPLER3D.
datatype_sampler ::= SAMPLERCUBE.
datatype_sampler ::= SAMPLER_STATE.
datatype_sampler ::= SAMPLERSTATE.
datatype_sampler ::= SAMPLERCOMPARISONSTATE.
datatype_scalar ::= BOOL.
datatype_scalar ::= INT.
datatype_scalar ::= UINT.
datatype_scalar ::= HALF.
datatype_scalar ::= FLOAT.
datatype_scalar ::= DOUBLE.
datatype_scalar ::= STRING. // this is for the effects framework, not HLSL.
datatype_scalar ::= SNORM FLOAT.
datatype_scalar ::= UNORM FLOAT.
datatype_scalar ::= BUFFER LT datatype_scalar GT.
// !!! FIXME: MSDN suggests that the matrix ones are just typedefs inserted
// !!! FIXME: before parsing begins, like:
// !!! FIXME: typedef matrix <bool,4,3> bool4x3;
// !!! FIXME: ...maybe we can rip these out of the grammar and just create
// !!! FIXME: them at startup?
datatype_vector ::= VECTOR LT datatype_scalar COMMA INT_CONSTANT GT.
datatype_vector ::= BOOL1.
datatype_vector ::= BOOL2.
datatype_vector ::= BOOL3.
datatype_vector ::= BOOL4.
datatype_vector ::= INT1.
datatype_vector ::= INT2.
datatype_vector ::= INT3.
datatype_vector ::= INT4.
datatype_vector ::= UINT1.
datatype_vector ::= UINT2.
datatype_vector ::= UINT3.
datatype_vector ::= UINT4.
datatype_vector ::= HALF1.
datatype_vector ::= HALF2.
datatype_vector ::= HALF3.
datatype_vector ::= HALF4.
datatype_vector ::= FLOAT1.
datatype_vector ::= FLOAT2.
datatype_vector ::= FLOAT3.
datatype_vector ::= FLOAT4.
datatype_vector ::= DOUBLE1.
datatype_vector ::= DOUBLE2.
datatype_vector ::= DOUBLE3.
datatype_vector ::= DOUBLE4.
datatype_matrix ::= MATRIX LT datatype_scalar COMMA INT_CONSTANT COMMA INT_CONSTANT GT.
datatype_matrix ::= BOOL1X1.
datatype_matrix ::= BOOL1X2.
datatype_matrix ::= BOOL1X3.
datatype_matrix ::= BOOL1X4.
datatype_matrix ::= BOOL2X1.
datatype_matrix ::= BOOL2X2.
datatype_matrix ::= BOOL2X3.
datatype_matrix ::= BOOL2X4.
datatype_matrix ::= BOOL3X1.
datatype_matrix ::= BOOL3X2.
datatype_matrix ::= BOOL3X3.
datatype_matrix ::= BOOL3X4.
datatype_matrix ::= BOOL4X1.
datatype_matrix ::= BOOL4X2.
datatype_matrix ::= BOOL4X3.
datatype_matrix ::= BOOL4X4.
datatype_matrix ::= INT1X1.
datatype_matrix ::= INT1X2.
datatype_matrix ::= INT1X3.
datatype_matrix ::= INT1X4.
datatype_matrix ::= INT2X1.
datatype_matrix ::= INT2X2.
datatype_matrix ::= INT2X3.
datatype_matrix ::= INT2X4.
datatype_matrix ::= INT3X1.
datatype_matrix ::= INT3X2.
datatype_matrix ::= INT3X3.
datatype_matrix ::= INT3X4.
datatype_matrix ::= INT4X1.
datatype_matrix ::= INT4X2.
datatype_matrix ::= INT4X3.
datatype_matrix ::= INT4X4.
datatype_matrix ::= UINT1X1.
datatype_matrix ::= UINT1X2.
datatype_matrix ::= UINT1X3.
datatype_matrix ::= UINT1X4.
datatype_matrix ::= UINT2X1.
datatype_matrix ::= UINT2X2.
datatype_matrix ::= UINT2X3.
datatype_matrix ::= UINT2X4.
datatype_matrix ::= UINT3X1.
datatype_matrix ::= UINT3X2.
datatype_matrix ::= UINT3X3.
datatype_matrix ::= UINT3X4.
datatype_matrix ::= UINT4X1.
datatype_matrix ::= UINT4X2.
datatype_matrix ::= UINT4X3.
datatype_matrix ::= UINT4X4.
datatype_matrix ::= HALF1X1.
datatype_matrix ::= HALF1X2.
datatype_matrix ::= HALF1X3.
datatype_matrix ::= HALF1X4.
datatype_matrix ::= HALF2X1.
datatype_matrix ::= HALF2X2.
datatype_matrix ::= HALF2X3.
datatype_matrix ::= HALF2X4.
datatype_matrix ::= HALF3X1.
datatype_matrix ::= HALF3X2.
datatype_matrix ::= HALF3X3.
datatype_matrix ::= HALF3X4.
datatype_matrix ::= HALF4X1.
datatype_matrix ::= HALF4X2.
datatype_matrix ::= HALF4X3.
datatype_matrix ::= HALF4X4.
datatype_matrix ::= FLOAT1X1.
datatype_matrix ::= FLOAT1X2.
datatype_matrix ::= FLOAT1X3.
datatype_matrix ::= FLOAT1X4.
datatype_matrix ::= FLOAT2X1.
datatype_matrix ::= FLOAT2X2.
datatype_matrix ::= FLOAT2X3.
datatype_matrix ::= FLOAT2X4.
datatype_matrix ::= FLOAT3X1.
datatype_matrix ::= FLOAT3X2.
datatype_matrix ::= FLOAT3X3.
datatype_matrix ::= FLOAT3X4.
datatype_matrix ::= FLOAT4X1.
datatype_matrix ::= FLOAT4X2.
datatype_matrix ::= FLOAT4X3.
datatype_matrix ::= FLOAT4X4.
datatype_matrix ::= DOUBLE1X1.
datatype_matrix ::= DOUBLE1X2.
datatype_matrix ::= DOUBLE1X3.
datatype_matrix ::= DOUBLE1X4.
datatype_matrix ::= DOUBLE2X1.
datatype_matrix ::= DOUBLE2X2.
datatype_matrix ::= DOUBLE2X3.
datatype_matrix ::= DOUBLE2X4.
datatype_matrix ::= DOUBLE3X1.
datatype_matrix ::= DOUBLE3X2.
datatype_matrix ::= DOUBLE3X3.
datatype_matrix ::= DOUBLE3X4.
datatype_matrix ::= DOUBLE4X1.
datatype_matrix ::= DOUBLE4X2.
datatype_matrix ::= DOUBLE4X3.
datatype_matrix ::= DOUBLE4X4.
statement_block ::= LBRACE RBRACE.
statement_block ::= LBRACE statement_list RBRACE.
statement_list ::= statement.
statement_list ::= statement_list statement.
statement ::= return_statement.
statement ::= BREAK SEMICOLON.
statement ::= CONTINUE SEMICOLON.
statement ::= DISCARD SEMICOLON.
statement ::= statement_block.
statement ::= for_statement.
statement ::= do_statement.
statement ::= while_statement.
statement ::= if_statement.
statement ::= switch_statement.
statement ::= variable_declaration.
statement ::= typedef_statement.
statement ::= expression_statement.
statement ::= struct_statement.
struct_statement ::= struct_declaration SEMICOLON.
expression_statement ::= SEMICOLON.
expression_statement ::= expression SEMICOLON.
return_statement ::= RETURN SEMICOLON.
return_statement ::= RETURN expression SEMICOLON.
while_statement ::= loop_attribute while_details.
while_statement ::= while_details.
while_details ::= WHILE LPAREN expression RPAREN statement.
for_statement ::= loop_attribute for_details.
for_statement ::= for_details.
for_details ::= FOR LPAREN expression SEMICOLON expression SEMICOLON expression RPAREN statement.
for_details ::= FOR LPAREN SEMICOLON SEMICOLON RPAREN statement.
for_details ::= FOR LPAREN SEMICOLON SEMICOLON expression RPAREN statement.
for_details ::= FOR LPAREN SEMICOLON expression SEMICOLON RPAREN statement.
for_details ::= FOR LPAREN SEMICOLON expression SEMICOLON expression RPAREN statement.
for_details ::= FOR LPAREN expression SEMICOLON SEMICOLON RPAREN statement.
for_details ::= FOR LPAREN expression SEMICOLON SEMICOLON expression RPAREN statement.
for_details ::= FOR LPAREN expression SEMICOLON expression SEMICOLON RPAREN statement.
loop_attribute ::= UNROLL LPAREN INT_CONSTANT RPAREN.
loop_attribute ::= UNROLL.
loop_attribute ::= LOOP.
do_statement ::= DO statement WHILE LPAREN expression RPAREN SEMICOLON.
if_statement ::= if_attribute IF LPAREN expression RPAREN statement.
if_statement ::= IF LPAREN expression RPAREN statement.
if_statement ::= if_attribute IF LPAREN expression RPAREN statement ELSE statement.
if_statement ::= IF LPAREN expression RPAREN statement ELSE statement.
if_attribute ::= BRANCH.
if_attribute ::= FLATTEN.
switch_statement ::= switch_attribute switch_details.
switch_statement ::= switch_details.
switch_details ::= SWITCH LPAREN expression RPAREN LBRACE switch_case_list RBRACE.
switch_attribute ::= FLATTEN.
switch_attribute ::= BRANCH.
switch_attribute ::= FORCECASE.
switch_attribute ::= CALL.
switch_case_list ::= switch_case.
switch_case_list ::= switch_case_list switch_case.
// You can do math here, apparently, as long as it produces an int constant.
// ...so "case 3+2:" works.
switch_case ::= CASE expression COLON statement_list.
switch_case ::= CASE expression COLON.
switch_case ::= DEFAULT COLON statement_list.
switch_case ::= DEFAULT COLON.
%type identifier { TokenData }
identifier(A) ::= IDENTIFIER(B).
{
A.token = B.token;
A.tokenlen = B.tokenlen;
}
// the expression stuff is based on Jeff Lee's ANSI C grammar.
primary_expr ::= identifier.
primary_expr ::= INT_CONSTANT.
primary_expr ::= FLOAT_CONSTANT.
primary_expr ::= STRING_LITERAL.
primary_expr ::= LPAREN expression RPAREN.
postfix_expr ::= primary_expr.
postfix_expr ::= postfix_expr LBRACKET expression RBRACKET.
postfix_expr ::= postfix_expr LPAREN RPAREN.
postfix_expr ::= postfix_expr LPAREN argument_expr_list RPAREN.
postfix_expr ::= datatype LPAREN argument_expr_list RPAREN. // HLSL constructor
postfix_expr ::= postfix_expr DOT identifier.
postfix_expr ::= postfix_expr PLUSPLUS.
postfix_expr ::= postfix_expr MINUSMINUS.
argument_expr_list ::= assignment_expr.
argument_expr_list ::= argument_expr_list COMMA assignment_expr.
unary_expr ::= postfix_expr.
unary_expr ::= PLUSPLUS unary_expr.
unary_expr ::= MINUSMINUS unary_expr.
unary_expr ::= unary_operator cast_expr.
unary_operator ::= PLUS.
unary_operator ::= MINUS.
unary_operator ::= COMPLEMENT.
unary_operator ::= EXCLAMATION.
cast_expr ::= unary_expr.
cast_expr ::= LPAREN datatype RPAREN cast_expr.
multiplicative_expr ::= cast_expr.
multiplicative_expr ::= multiplicative_expr STAR cast_expr.
multiplicative_expr ::= multiplicative_expr SLASH cast_expr.
multiplicative_expr ::= multiplicative_expr PERCENT cast_expr.
additive_expr ::= multiplicative_expr.
additive_expr ::= additive_expr PLUS multiplicative_expr.
additive_expr ::= additive_expr MINUS multiplicative_expr.
shift_expr ::= additive_expr.
shift_expr ::= shift_expr LSHIFT additive_expr.
shift_expr ::= shift_expr RSHIFT additive_expr.
relational_expr ::= shift_expr.
relational_expr ::= relational_expr LT shift_expr.
relational_expr ::= relational_expr GT shift_expr.
relational_expr ::= relational_expr LEQ shift_expr.
relational_expr ::= relational_expr GEQ shift_expr.
equality_expr ::= relational_expr.
equality_expr ::= equality_expr EQL relational_expr.
equality_expr ::= equality_expr NEQ relational_expr.
and_expr ::= equality_expr.
and_expr ::= and_expr AND equality_expr.
exclusive_or_expr ::= and_expr.
exclusive_or_expr ::= exclusive_or_expr XOR and_expr.
inclusive_or_expr ::= exclusive_or_expr.
inclusive_or_expr ::= inclusive_or_expr OR exclusive_or_expr.
logical_and_expr ::= inclusive_or_expr.
logical_and_expr ::= logical_and_expr ANDAND inclusive_or_expr.
logical_or_expr ::= logical_and_expr.
logical_or_expr ::= logical_or_expr OROR logical_and_expr.
conditional_expr ::= logical_or_expr.
conditional_expr ::= logical_or_expr QUESTION logical_or_expr COLON conditional_expr.
assignment_expr ::= conditional_expr.
assignment_expr ::= unary_expr assignment_operator assignment_expr.
assignment_operator ::= ASSIGN.
assignment_operator ::= MULASSIGN.
assignment_operator ::= DIVASSIGN.
assignment_operator ::= MODASSIGN.
assignment_operator ::= ADDASSIGN.
assignment_operator ::= SUBASSIGN.
assignment_operator ::= LSHIFTASSIGN.
assignment_operator ::= RSHIFTASSIGN.
assignment_operator ::= ANDASSIGN.
assignment_operator ::= XORASSIGN.
assignment_operator ::= ORASSIGN.
expression ::= assignment_expr.
expression ::= expression COMMA assignment_expr.
// end of mojoshader_parser_hlsl.lemon ...