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package dotty.tools.dotc
package core
package tasty
/************************************************************
Notation:
We use BNF notation. Terminal symbols start with at least two
consecutive upper case letters. Each terminal is represented as a
single byte tag. Non-terminals are mixed case. Prefixes of the form
lower case letter*_ are for explanation of semantic content only, they
can be dropped without changing the grammar.
Micro-syntax:
LongInt = Digit* StopDigit // big endian 2's complement, value fits in a Long w/o overflow
Int = LongInt // big endian 2's complement, fits in an Int w/o overflow
Nat = LongInt // non-negative value, fits in an Int without overflow
Digit = 0 | ... | 127
StopDigit = 128 | ... | 255 // value = digit - 128
Macro-format:
File = Header majorVersion_Nat minorVersion_Nat UUID
nameTable_Length Name* Section*
Header = 0x5CA1AB1F
UUID = Byte*16 // random UUID
Section = NameRef Length Bytes
Length = Nat // length of rest of entry in bytes
Name = UTF8 Length UTF8-CodePoint*
QUALIFIED Length qualified_NameRef selector_NameRef
SIGNED Length original_NameRef resultSig_NameRef paramSig_NameRef*
EXPANDED Length original_NameRef
OBJECTCLASS Length module_NameRef
SUPERACCESSOR Length accessed_NameRef
DEFAULTGETTER Length method_NameRef paramNumber_Nat
SHADOWED Length original_NameRef
MANGLED Length mangle_NameRef name_NameRef
...
NameRef = Nat // ordinal number of name in name table, starting from 1.
Note: Unqualified names in the name table are strings. The context decides whether a name is
a type-name or a term-name. The same string can represent both.
Standard-Section: "ASTs" TopLevelStat*
TopLevelStat = PACKAGE Length Path TopLevelStat*
Stat
Stat = Term
VALDEF Length NameRef Type rhs_Term? Modifier*
DEFDEF Length NameRef TypeParam* Params* return_Type rhs_Term?
Modifier*
TYPEDEF Length NameRef (Type | Template) Modifier*
IMPORT Length qual_Term Selector*
Selector = IMPORTED name_NameRef
RENAMED Length from_NameRef to_NameRef
// Imports are for scala.meta, they are not used in the backend
TypeParam = TYPEPARAM Length NameRef Type Modifier*
Params = PARAMS Length Param*
Param = PARAM Length NameRef Type rhs_Term? Modifier* // rhs_Term is present in the case of an aliased class parameter
Template = TEMPLATE Length TypeParam* Param* Parent* Self? Stat* // Stat* always starts with the primary constructor.
Parent = Application
Type
Self = SELFDEF selfName_NameRef selfType_Type
Term = Path
Application
IDENT NameRef Type // used when ident’s type is not a TermRef
SELECT possiblySigned_NameRef qual_Term
NEW cls_Type
SUPER Length this_Term mixinTrait_Type?
TYPED Length expr_Term ascription_Type
NAMEDARG Length paramName_NameRef arg_Term
ASSIGN Length lhs_Term rhs_Term
BLOCK Length expr_Term Stat*
LAMBDA Length meth_Term target_Type
IF Length cond_Term then_Term else_Term
MATCH Length sel_Term CaseDef*
TRY Length expr_Term CaseDef* finalizer_Term?
RETURN Length meth_ASTRef expr_Term?
REPEATED Length elem_Type elem_Term*
BIND Length boundName_NameRef patType_Type pat_Term
ALTERNATIVE Length alt_Term*
UNAPPLY Length fun_Term ImplicitArg* pat_Type pat_Term*
EMPTYTREE
SHARED term_ASTRef
Application = APPLY Length fn_Term arg_Term*
TYPEAPPLY Length fn_Term arg_Type*
CaseDef = CASEDEF Length pat_Term rhs_Tree guard_Tree?
ImplicitArg = IMPLICITARG arg_Term
ASTRef = Nat // byte position in AST payload
Path = Constant
TERMREFdirect sym_ASTRef
TERMREFsymbol sym_ASTRef qual_Type
TERMREFpkg fullyQualified_NameRef
TERMREF possiblySigned_NameRef qual_Type
THIS clsRef_Type
RECthis recType_ASTRef
SHARED path_ASTRef
Constant = UNITconst
FALSEconst
TRUEconst
BYTEconst Int
SHORTconst Int
CHARconst Nat
INTconst Int
LONGconst LongInt
FLOATconst Int
DOUBLEconst LongInt
STRINGconst NameRef
NULLconst
CLASSconst Type
ENUMconst Path
Type = Path
TYPEREFdirect sym_ASTRef
TYPEREFsymbol sym_ASTRef qual_Type
TYPEREFpkg fullyQualified_NameRef
TYPEREF possiblySigned_NameRef qual_Type
RECtype parent_Type
SUPERtype Length this_Type underlying_Type
REFINEDtype Length underlying_Type refinement_NameRef info_Type
APPLIEDtype Length tycon_Type arg_Type*
TYPEBOUNDS Length low_Type high_Type
TYPEALIAS Length alias_Type (COVARIANT | CONTRAVARIANT)?
ANNOTATED Length underlying_Type fullAnnotation_Term
ANDtype Length left_Type right_Type
ORtype Length left_Type right_Type
BIND Length boundName_NameRef bounds_Type
// for type-variables defined in a type pattern
BYNAMEtype underlying_Type
LAMBDAtype Length result_Type NamesTypes // variance encoded in front of name: +/-/=
POLYtype Length result_Type NamesTypes // needed for refinements
METHODtype Length result_Type NamesTypes // needed for refinements
PARAMtype Length binder_ASTref paramNum_Nat // needed for refinements
SHARED type_ASTRef
NamesTypes = ParamType*
NameType = paramName_NameRef typeOrBounds_ASTRef
Modifier = PRIVATE
INTERNAL // package private
PROTECTED
PRIVATEqualified qualifier_Type // will be dropped
PROTECTEDqualified qualifier_Type // will be dropped
ABSTRACT
FINAL
SEALED
CASE
IMPLICIT
LAZY
OVERRIDE
INLINE // macro
STATIC // mapped to static Java member
OBJECT // an object or its class
TRAIT // a trait
LOCAL // private[this] or protected[this]
SYNTHETIC // generated by Scala compiler
ARTIFACT // to be tagged Java Synthetic
MUTABLE // a var
LABEL // method generated as a label
FIELDaccessor // getter or setter
CASEaccessor // getter for case class param
COVARIANT // type param marked “+”
CONTRAVARIANT // type param marked “-”
SCALA2X // Imported from Scala2.x
DEFAULTparameterized // Method with default params
INSUPERCALL // defined in the argument of a constructor supercall
STABLE // Method that is assumed to be stable
Annotation
Annotation = ANNOTATION Length tycon_Type fullAnnotation_Term
Note: Tree tags are grouped into 5 categories that determine what follows, and thus allow to compute the size of the tagged tree in a generic way.
Category 1 (tags 0-63) : tag
Category 2 (tags 64-95) : tag Nat
Category 3 (tags 96-111) : tag AST
Category 4 (tags 112-127): tag Nat AST
Category 5 (tags 128-255): tag Length <payload>
Standard Section: "Positions" Assoc*
Assoc = Header offset_Delta? offset_Delta?
Header = addr_Delta + // in one Nat: difference of address to last recorded node << 2 +
hasStartDiff + // one bit indicating whether there follows a start address delta << 1
hasEndDiff // one bit indicating whether there follows an end address delta
// Nodes which have the same positions as their parents are omitted.
// offset_Deltas give difference of start/end offset wrt to the
// same offset in the previously recorded node (or 0 for the first recorded node)
Delta = Int // Difference between consecutive offsets,
**************************************************************************************/
object TastyFormat {
final val header = Array(0x5C, 0xA1, 0xAB, 0x1F)
final val MajorVersion = 0
final val MinorVersion = 5
// Name tags
final val UTF8 = 1
final val QUALIFIED = 2
final val SIGNED = 3
final val EXPANDED = 4
final val OBJECTCLASS = 5
final val SUPERACCESSOR = 6
final val DEFAULTGETTER = 7
final val SHADOWED = 8
// AST tags
final val UNITconst = 2
final val FALSEconst = 3
final val TRUEconst = 4
final val NULLconst = 5
final val PRIVATE = 6
final val INTERNAL = 7
final val PROTECTED = 8
final val ABSTRACT = 9
final val FINAL = 10
final val SEALED = 11
final val CASE = 12
final val IMPLICIT = 13
final val LAZY = 14
final val OVERRIDE = 15
final val INLINE = 16
final val STATIC = 17
final val OBJECT = 18
final val TRAIT = 19
final val LOCAL = 20
final val SYNTHETIC = 21
final val ARTIFACT = 22
final val MUTABLE = 23
final val LABEL = 24
final val FIELDaccessor = 25
final val CASEaccessor = 26
final val COVARIANT = 27
final val CONTRAVARIANT = 28
final val SCALA2X = 29
final val DEFAULTparameterized = 30
final val INSUPERCALL = 31
final val STABLE = 32
final val SHARED = 64
final val TERMREFdirect = 65
final val TYPEREFdirect = 66
final val TERMREFpkg = 67
final val TYPEREFpkg = 68
final val RECthis = 69
final val BYTEconst = 70
final val SHORTconst = 71
final val CHARconst = 72
final val INTconst = 73
final val LONGconst = 74
final val FLOATconst = 75
final val DOUBLEconst = 76
final val STRINGconst = 77
final val IMPORTED = 78
final val THIS = 96
final val CLASSconst = 97
final val ENUMconst = 98
final val BYNAMEtype = 99
final val NEW = 100
final val IMPLICITarg = 101
final val PRIVATEqualified = 102
final val PROTECTEDqualified = 103
final val RECtype = 104
final val IDENT = 112
final val SELECT = 113
final val TERMREFsymbol = 114
final val TERMREF = 115
final val TYPEREFsymbol = 116
final val TYPEREF = 117
final val SELFDEF = 118
final val PACKAGE = 128
final val VALDEF = 129
final val DEFDEF = 130
final val TYPEDEF = 131
final val IMPORT = 132
final val TYPEPARAM = 133
final val PARAMS = 134
final val PARAM = 136
final val RENAMED = 138
final val APPLY = 139
final val TYPEAPPLY = 140
final val TYPED = 143
final val NAMEDARG = 144
final val ASSIGN = 145
final val BLOCK = 146
final val IF = 147
final val LAMBDA = 148
final val MATCH = 149
final val RETURN = 150
final val TRY = 151
final val REPEATED = 153
final val BIND = 154
final val ALTERNATIVE = 155
final val UNAPPLY = 156
final val ANNOTATED = 157
final val CASEDEF = 158
final val TEMPLATE = 160
final val SUPER = 163
final val SUPERtype = 166
final val REFINEDtype = 167
final val APPLIEDtype = 168
final val TYPEBOUNDS = 169
final val TYPEALIAS = 170
final val ANDtype = 171
final val ORtype = 172
final val METHODtype = 174
final val POLYtype = 175
final val LAMBDAtype = 176
final val PARAMtype = 177
final val ANNOTATION = 178
final val firstSimpleTreeTag = UNITconst
final val firstNatTreeTag = SHARED
final val firstASTTreeTag = THIS
final val firstNatASTTreeTag = IDENT
final val firstLengthTreeTag = PACKAGE
def isParamTag(tag: Int) = tag == PARAM || tag == TYPEPARAM
def isModifierTag(tag: Int) = tag match {
case PRIVATE
| INTERNAL
| PROTECTED
| ABSTRACT
| FINAL
| SEALED
| CASE
| IMPLICIT
| LAZY
| OVERRIDE
| INLINE
| STATIC
| OBJECT
| TRAIT
| LOCAL
| SYNTHETIC
| ARTIFACT
| MUTABLE
| LABEL
| FIELDaccessor
| CASEaccessor
| COVARIANT
| CONTRAVARIANT
| SCALA2X
| DEFAULTparameterized
| INSUPERCALL
| STABLE
| ANNOTATION
| PRIVATEqualified
| PROTECTEDqualified => true
case _ => false
}
def nameTagToString(tag: Int): String = tag match {
case UTF8 => "UTF8"
case QUALIFIED => "QUALIFIED"
case SIGNED => "SIGNED"
case EXPANDED => "EXPANDED"
case OBJECTCLASS => "OBJECTCLASS"
case SUPERACCESSOR => "SUPERACCESSOR"
case DEFAULTGETTER => "DEFAULTGETTER"
}
def astTagToString(tag: Int): String = tag match {
case UNITconst => "UNITconst"
case FALSEconst => "FALSEconst"
case TRUEconst => "TRUEconst"
case NULLconst => "NULLconst"
case PRIVATE => "PRIVATE"
case INTERNAL => "INTERNAL"
case PROTECTED => "PROTECTED"
case ABSTRACT => "ABSTRACT"
case FINAL => "FINAL"
case SEALED => "SEALED"
case CASE => "CASE"
case IMPLICIT => "IMPLICIT"
case LAZY => "LAZY"
case OVERRIDE => "OVERRIDE"
case INLINE => "INLINE"
case STATIC => "STATIC"
case OBJECT => "OBJECT"
case TRAIT => "TRAIT"
case LOCAL => "LOCAL"
case SYNTHETIC => "SYNTHETIC"
case ARTIFACT => "ARTIFACT"
case MUTABLE => "MUTABLE"
case LABEL => "LABEL"
case FIELDaccessor => "FIELDaccessor"
case CASEaccessor => "CASEaccessor"
case COVARIANT => "COVARIANT"
case CONTRAVARIANT => "CONTRAVARIANT"
case SCALA2X => "SCALA2X"
case DEFAULTparameterized => "DEFAULTparameterized"
case INSUPERCALL => "INSUPERCALL"
case STABLE => "STABLE"
case SHARED => "SHARED"
case TERMREFdirect => "TERMREFdirect"
case TYPEREFdirect => "TYPEREFdirect"
case TERMREFpkg => "TERMREFpkg"
case TYPEREFpkg => "TYPEREFpkg"
case RECthis => "RECthis"
case BYTEconst => "BYTEconst"
case SHORTconst => "SHORTconst"
case CHARconst => "CHARconst"
case INTconst => "INTconst"
case LONGconst => "LONGconst"
case FLOATconst => "FLOATconst"
case DOUBLEconst => "DOUBLEconst"
case STRINGconst => "STRINGconst"
case RECtype => "RECtype"
case IDENT => "IDENT"
case SELECT => "SELECT"
case TERMREFsymbol => "TERMREFsymbol"
case TERMREF => "TERMREF"
case TYPEREFsymbol => "TYPEREFsymbol"
case TYPEREF => "TYPEREF"
case PACKAGE => "PACKAGE"
case VALDEF => "VALDEF"
case DEFDEF => "DEFDEF"
case TYPEDEF => "TYPEDEF"
case IMPORT => "IMPORT"
case TYPEPARAM => "TYPEPARAM"
case PARAMS => "PARAMS"
case PARAM => "PARAM"
case IMPORTED => "IMPORTED"
case RENAMED => "RENAMED"
case APPLY => "APPLY"
case TYPEAPPLY => "TYPEAPPLY"
case NEW => "NEW"
case TYPED => "TYPED"
case NAMEDARG => "NAMEDARG"
case ASSIGN => "ASSIGN"
case BLOCK => "BLOCK"
case IF => "IF"
case LAMBDA => "LAMBDA"
case MATCH => "MATCH"
case RETURN => "RETURN"
case TRY => "TRY"
case REPEATED => "REPEATED"
case BIND => "BIND"
case ALTERNATIVE => "ALTERNATIVE"
case UNAPPLY => "UNAPPLY"
case ANNOTATED => "ANNOTATED"
case CASEDEF => "CASEDEF"
case IMPLICITarg => "IMPLICITarg"
case TEMPLATE => "TEMPLATE"
case SELFDEF => "SELFDEF"
case THIS => "THIS"
case SUPER => "SUPER"
case CLASSconst => "CLASSconst"
case ENUMconst => "ENUMconst"
case SUPERtype => "SUPERtype"
case REFINEDtype => "REFINEDtype"
case APPLIEDtype => "APPLIEDtype"
case TYPEBOUNDS => "TYPEBOUNDS"
case TYPEALIAS => "TYPEALIAS"
case ANDtype => "ANDtype"
case ORtype => "ORtype"
case BYNAMEtype => "BYNAMEtype"
case POLYtype => "POLYtype"
case METHODtype => "METHODtype"
case PARAMtype => "PARAMtype"
case ANNOTATION => "ANNOTATION"
case PRIVATEqualified => "PRIVATEqualified"
case PROTECTEDqualified => "PROTECTEDqualified"
}
/** @return If non-negative, the number of leading references of a length/trees entry.
* If negative, minus the number of leading non-reference trees.
*/
def numRefs(tag: Int) = tag match {
case VALDEF | DEFDEF | TYPEDEF | TYPEPARAM | PARAM | NAMEDARG | RETURN | BIND |
SELFDEF | REFINEDtype => 1
case RENAMED | PARAMtype => 2
case POLYtype | METHODtype => -1
case _ => 0
}
/** Map between variances and name prefixes */
val varianceToPrefix = Map(-1 -> '-', 0 -> '=', 1 -> '+')
val prefixToVariance = Map('-' -> -1, '=' -> 0, '+' -> 1)
}
|