/
type.scm
497 lines (463 loc) · 20 KB
/
type.scm
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;;;
;;; gauche.cgen.type - Stub type management
;;;
;;; Copyright (c) 2004-2024 Shiro Kawai <shiro@acm.org>
;;;
;;; Redistribution and use in source and binary forms, with or without
;;; modification, are permitted provided that the following conditions
;;; are met:
;;;
;;; 1. Redistributions of source code must retain the above copyright
;;; notice, this list of conditions and the following disclaimer.
;;;
;;; 2. Redistributions in binary form must reproduce the above copyright
;;; notice, this list of conditions and the following disclaimer in the
;;; documentation and/or other materials provided with the distribution.
;;;
;;; 3. Neither the name of the authors nor the names of its contributors
;;; may be used to endorse or promote products derived from this
;;; software without specific prior written permission.
;;;
;;; THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
;;; "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
;;; LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
;;; A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
;;; OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
;;; SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
;;; TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
;;; PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
;;; LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
;;; NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
;;; SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
;;;
(define-module gauche.cgen.type
(use srfi.13)
(use text.tr)
(use util.match)
(use gauche.mop.instance-pool)
(export <cgen-type> cgen-type-from-name make-cgen-type
cgen-canonical-typed-var-1
cgen-canonical-typed-var-list
cgen-boxer-name cgen-unboxer-name cgen-pred-name
cgen-box-expr cgen-box-tail-expr cgen-unbox-expr cgen-pred-expr
cgen-type-maybe? cgen-return-stmt)
)
(select-module gauche.cgen.type)
;; Stub types augment Gauche's runtime type system, adding information
;; on how to generate C code fragments to typecheck, box and unbox the
;; value of the given type.
;;
;; Each stub type has a "boxer" and an "unboxer". A boxer is a C name
;; of a function or a macro that takes an object of C type of the stub
;; type and returns a Scheme object. An unboxer is a C name of a function
;; or a macro that takes Scheme object and checks its vailidy, then
;; returns a C object of the C type or throws an error.
;;
;; We have a few categories of stub types.
;;
;; - Native types. Some native types can represent a subset of Scheme
;; types; e.g. <int16> native type corresponds to C's int16_t,
;; and covers a subset of Scheme <integer> type. See src/libtype.scm
;; for those native types.
;;
;; - C-class types. These are Scheme object whose structure is defined in C.
;; They can be treated as ScmObj or can be casted to the specific C type;
;; e.g. <symbol> can be casted to ScmSymbol*.
;; Its unboxer is ScmObj -> C-TYPE*, and boxer is C-TYPE* -> ScmObj.
;;
;; - Pass-through types. These are Scheme object that are also handled
;; as ScmObj in C-level. Stub types only typecheck, and its boxer and
;; unboxer are just identity. It can be either purely-Scheme-defined
;; objects, or an object that can take multiple representations
;; (e.g. <integer> can be a fixnum or ScmBignum*, so the stub generator
;; passes through it, and the C routine handles the internals.)
;;
;; - Maybe types. (<?> TYPE). In stub context, we only concern maybe type
;; that can be unboxed into a C pointer type. In addition to the objects
;; of TYPE, it maps Scheme's #f to C's NULL and vice versa.
;; For the convenience, maybe type can be notated as TYPE? in the stub,
;; e.g. <port>?
;;
;; In general, types defined in extensions can't be directly accesible from
;; other extensions at C level. So we don't need to carry around stub types
;; across boundary of extensions. Each extension can only use
;; the stub types provided from Gauche core, or the stub types explicitly
;; defined within it.
;; The stub types provided from Gauche core are defined in this module.
;; Each <cgen-type> has a corresponding Gauche type. However, when
;; compiling an extension that introduces a new type, the compiling
;; Gauche may not know the type that's being defined. So <cgen-types> are
;; catalogued with the 'name' of the corresponding Gauche type, rather than
;; the type object itself.
;; Stub type definition
(define-class <cgen-type> (<instance-pool-mixin>)
((name :init-keyword :name)
;; ::<symbol> - name of the Gauche type.
(scheme-type :init-keyword :scheme-type)
;; class or type. can be #f if the type does not exist at runtime yet.
(c-type :init-keyword :c-type)
;; ::<string> - C type name this stub type represents
(description :init-keyword :description)
;; ::<string> - used in the type error message
(cclass :init-keyword :cclass :init-value #f)
;; If this cgen-type is for define-cclass'ed class, this slot holds
;; <cclass>.
;; The following field should be private. Use cgen-box-expr etc.
(%c-predicate :init-keyword :c-predicate)
;; ::<string> - name of a C function (macro) to find out the given
;; ScmObj has a valid type for this stub type.
(%unboxer :init-keyword :unboxer)
;; ::<string> - name of a C function (macro) that takes Scheme object
;; and returns a C object.
(%boxer :init-keyword :boxer :init-value "SCM_OBJ_SAFE")
;; ::<string> - name of a C function (macro) that takes C object
;; and returns a Scheme Object.
(%maybe :init-keyword :maybe :init-value #f)
;; ::<type>? - base type, if this is 'maybe' qualified type.
))
(define-method write-object ((ct <cgen-type>) port)
(format port "#<cgen-type ~a>" (~ ct'name)))
;; Lookup/create a cgen type from Gauche type name
(define (cgen-type-from-name name)
(or (find (lambda (type) (eq? (~ type'name) name))
(instance-pool->list <cgen-type>))
;; when 'maybe' qualified type is used for the first time, we
;; create it from the base type.
(and-let* ((m (#/\?$/ (symbol->string name)))
(basename (string->symbol (m 'before)))
(basetype (cgen-type-from-name basename)))
(make <cgen-type>
:name name
:scheme-type #f ;; can be (<?> TYPE) after 0.9.11 release
:c-type (~ basetype'c-type)
:description #"~(~ basetype'description) or #f"
:c-predicate (~ basetype'%c-predicate)
:unboxer (~ basetype'%unboxer)
:boxer (~ basetype'%boxer)
:maybe basetype))))
;; accessor
(define (cgen-type-maybe? type)
(boolean (~ type'%maybe)))
;; These could be #f
(define (cgen-boxer-name type) (~ type'%boxer))
(define (cgen-unboxer-name type) (~ type'%unboxer))
(define (cgen-pred-name type) (~ type'%c-predicate))
;; Create a new cgen-type.
;; Many cgen-types follows a specific convention to name boxer/unboxer etc,
;; and make-cgen-type assumes the convention if they are not provided.
(define (make-cgen-type name scheme-type c-type :optional (desc #f) (c-pred #f)
(unbox #f) (box #f))
(define (strip<> name) (string-trim-both name #[<>]))
(define (default-cpred name)
(if (#/-/ name)
(string-append "SCM_"
(string-tr (strip<> name) "a-z-" "A-Z_")
"_P")
#"SCM_~(string-upcase (strip<> name))P"))
(define (default-unbox name)
#"SCM_~(string-tr (strip<> name) \"a-z-\" \"A-Z_\")")
(define (default-box name)
#"SCM_MAKE_~(string-tr (strip<> name) \"a-z-\" \"A-Z_\")")
(make <cgen-type>
:name name :scheme-type scheme-type :c-type c-type
:description (or desc (x->string name))
:c-predicate (or c-pred (default-cpred (x->string name)))
:unboxer (or unbox (default-unbox (x->string name)))
:boxer (or box "SCM_OBJ_SAFE")))
;; Stub types corresponding to native types.
(let ()
(define (%native native-type pred unbox box)
(make <cgen-type>
:name (~ native-type'name)
:scheme-type native-type
:c-type (~ native-type'c-type-name)
:description (~ native-type'c-type-name)
:c-predicate pred
:unboxer unbox
:boxer box
:maybe #f))
(%native <fixnum> "SCM_INTP" "SCM_INT_VALUE" "SCM_MAKE_INT")
(%native <int> "SCM_INTEGERP" "Scm_GetInteger" "Scm_MakeInteger")
(%native <long> "SCM_INTEGERP" "Scm_GetInteger" "Scm_MakeInteger")
(%native <short> "SCM_INTP" "(short)SCM_INT_VALUE" "SCM_MAKE_INT")
(%native <int8> "SCM_INTEGERP" "Scm_GetInteger8" "Scm_MakeInteger")
(%native <int16> "SCM_INTEGERP" "Scm_GetInteger16" "Scm_MakeInteger")
(%native <int32> "SCM_INTEGERP" "Scm_GetInteger32" "Scm_MakeInteger")
(%native <int64> "SCM_INTEGERP" "Scm_GetInteger64" "Scm_MakeInteger")
(%native <uint> "SCM_UINTEGERP" "Scm_GetIntegerU" "Scm_MakeIntegerU")
(%native <ulong> "SCM_UINTEGERP" "Scm_GetIntegerU" "Scm_MakeIntegerU")
(%native <ushort> "SCM_UINTEGERP" "(unsigned short)Scm_GetIntegerU" "Scm_MakeIntegerU")
(%native <uint8> "SCM_UINTP" "Scm_GetIntegerU8" "Scm_MakeIntegerU")
(%native <uint16> "SCM_UINTP" "Scm_GetIntegerU16" "Scm_MakeIntegerU")
(%native <uint32> "SCM_UINTEGERP" "Scm_GetIntegerU32" "Scm_MakeIntegerU")
(%native <uint64> "SCM_UINTEGERP" "Scm_GetIntegerU64" "Scm_MakeIntegerU")
(%native <float> "SCM_REALP" "(float)Scm_GetDouble" "Scm_MakeFlonum")
(%native <double> "SCM_REALP" "Scm_GetDouble" "Scm_VMReturnFlonum")
(%native <size_t> "Scm_IntegerFitsSizeP" "Scm_IntegerToSize" "Scm_SizeToInteger")
(%native <ssize_t> "Scm_IntegerFitsSsizeP" "Scm_IntegerToSsize" "Scm_SsizeToInteger")
(%native <ptrdiff_t> "Scm_IntegerFitsPtrdiffP" "Scm_IntegerToPtrdiff" "Scm_PtrdiffToInteger")
(%native <off_t> "Scm_IntegerFitsOffsetP" "Scm_IntegerToOffset" "Scm_OffsetToInteger")
(%native <intptr_t> "Scm_IntegerFitsIntptrP" "Scm_IntegerToIntptr" "Scm_IntptrToInteger")
(%native <uintptr_t> "Scm_IntegerFitsUintptrP" "Scm_IntegerToUintptr" "Scm_UintptrToInteger")
(%native <closure> "SCM_CLOSUREP" "SCM_CLOSURE" "SCM_OBJ")
(%native <void> "" "" "SCM_VOID_RETURN_VALUE")
(%native <const-cstring> "SCM_STRINGP" "SCM_STRING_CONST_CSTRING" "SCM_MAKE_STR_COPYING")
)
;; A few native types that has corresponding actual Scheme types.
;; NB: <real> should be a pass-through type, for coercing to double can lose
;; information. To interface with C double or float, you can use <double>
;; or <float>. We keep it so for the backward compatibility, but at some
;; point we'll change it to a pass-through type.
(make-cgen-type '<real> <real> "double" "real number"
"SCM_REALP" "Scm_GetDouble" "Scm_MakeFlonum")
(make-cgen-type '<char> <char> "ScmChar" "character"
"SCM_CHARP" "SCM_CHAR_VALUE" "SCM_MAKE_CHAR")
(make-cgen-type '<boolean> <boolean> "int" "boolean"
"SCM_BOOLP" "SCM_BOOL_VALUE" "SCM_MAKE_BOOL")
;; Pass-through types
(let ()
(define (%pass-through class desc pred)
(make <cgen-type>
:name (class-name class)
:scheme-type class
:c-type "ScmObj"
:description desc
:c-predicate pred
:unboxer "" :maybe #f))
(%pass-through <integer> "exact integer" "SCM_INTEGERP")
(%pass-through <number> "number" "SCM_NUMBERP")
(%pass-through <top> "scheme object" "")
(%pass-through <list> "list" "SCM_LISTP")
(%pass-through <string-cursor> "string cursor" "Scm_StringCursorP")
)
;; C-class types
(let ()
(define (%cclass class c-type :optional (pred #f) (unbox #f))
(make-cgen-type (class-name class) class c-type
(x->string (class-name class)) pred unbox))
(%cclass <pair> "ScmPair*")
(%cclass <vector> "ScmVector*")
(%cclass <uvector> "ScmUVector*")
(%cclass <s8vector> "ScmUVector*")
(%cclass <u8vector> "ScmUVector*")
(%cclass <s16vector> "ScmUVector*")
(%cclass <u16vector> "ScmUVector*")
(%cclass <s32vector> "ScmUVector*")
(%cclass <u32vector> "ScmUVector*")
(%cclass <s64vector> "ScmUVector*")
(%cclass <u64vector> "ScmUVector*")
(%cclass <f16vector> "ScmUVector*")
(%cclass <f32vector> "ScmUVector*")
(%cclass <f64vector> "ScmUVector*")
(%cclass <c32vector> "ScmUVector*")
(%cclass <c64vector> "ScmUVector*")
(%cclass <c128vector> "ScmUVector*")
(%cclass <bitvector> "ScmBitvector*")
(%cclass <string> "ScmString*")
(%cclass <symbol> "ScmSymbol*")
(%cclass <keyword> "ScmKeyword*")
(%cclass <identifier> "ScmIdentifier*")
(%cclass <char-set> "ScmCharSet*")
(%cclass <regexp> "ScmRegexp*")
(%cclass <regmatch> "ScmRegMatch*")
(%cclass <port> "ScmPort*")
(%cclass <input-port> "ScmPort*" "SCM_IPORTP" "SCM_PORT")
(%cclass <output-port> "ScmPort*" "SCM_OPORTP" "SCM_PORT")
(%cclass <procedure> "ScmProcedure*")
(%cclass <promise> "ScmPromise*")
(%cclass <comparator> "ScmComparator*")
(%cclass <hash-table> "ScmHashTable*")
(%cclass <tree-map> "ScmTreeMap*")
(%cclass <class> "ScmClass*")
(%cclass <method> "ScmMethod*")
(%cclass <module> "ScmModule*")
(%cclass <thread> "ScmVM*" "SCM_VMP" "SCM_VM")
(%cclass <weak-vector> "ScmWeakVector*")
(%cclass <weak-hash-table> "ScmWeakHashTable*")
(%cclass <compiled-code> "ScmCompiledCode*")
(%cclass <foreign-pointer> "ScmForeignPointer*")
(%cclass <box> "ScmBox*")
(%cclass <thread-local> "ScmThreadLocal*")
(%cclass <primitive-parameter> "ScmPrimitiveParameter*")
(%cclass <parameterization> "ScmParameterization*")
(%cclass <continuation-mark-set> "ScmContinuationMarkSet*")
(%cclass <dlobj> "ScmDLObj*")
(%cclass <dlptr> "ScmObj" "Scm_DLPtrP" "SCM_OBJ")
(%cclass <sys-group> "ScmSysGroup*")
(%cclass <sys-passwd> "ScmSysPasswd*")
(%cclass <sys-sigset> "ScmSysSigset*")
(%cclass <sys-stat> "ScmSysStat*")
(%cclass <time> "ScmTime*")
(%cclass <sys-fdset> "ScmSysFdset*")
;; NB: <sys-tm> is defined using define-cstruct in libsys.scm, and its
;; C type isn't visible from outside.
;;(%cclass <sys-tm> "ScmSysTm*")
;; Exception - those classes are in the core but defined in gauche.threads.
(make-cgen-type '<mutex>
(with-module gauche.threads <mutex>)
"ScmMutex*" "<mutex>")
(make-cgen-type '<condition-variable>
(with-module gauche.threads <condition-variable>)
"ScmConditionVariable*"
"<condition-variable>")
)
;;
;; Generating C expressions from type info
;;
;; cgen-box-tail-expr can be used when the generated value will be
;; immediately returned from SUBR. The only difference from cgen-box-expr
;; is the case for flonums, where we can use Scm_VMReturnFlonum.
;;
(define (cgen-box-expr type c-expr)
(let1 boxer (or (~ type'%boxer) "")
(if (cgen-type-maybe? type)
#"SCM_MAKE_MAYBE(~|boxer|, ~c-expr)"
#"~|boxer|(~c-expr)")))
(define (cgen-box-tail-expr type c-expr)
(let1 boxer (if (memq (~ type'name) '(<real> <float> <double>))
"Scm_VMReturnFlonum"
(or (~ type'%boxer) ""))
(if (cgen-type-maybe? type)
#"SCM_MAKE_MAYBE(~|boxer|, ~c-expr)"
#"~|boxer|(~c-expr)")))
(define (cgen-unbox-expr type c-expr)
(let1 unboxer (or (~ type'%unboxer) "")
(if (cgen-type-maybe? type)
#"SCM_MAYBE(~|unboxer|, ~c-expr)"
#"~|unboxer|(~c-expr)")))
(define (cgen-pred-expr type c-expr)
(if-let1 pred (~ type'%c-predicate)
(if (cgen-type-maybe? type)
#"SCM_MAYBE_P(~|pred|, ~c-expr)"
#"~|pred|(~c-expr)")
"TRUE"))
(define (cgen-return-stmt expr)
#"SCM_RETURN(~expr);")
;;;
;;; Parsing typed variables.
;;;
;
;; For conciseness and readability, we allow varaible name and type
;; can be concatenated, so the following forms are allowed:
;;
;; var :: type ; proper form
;; var::type ; concatenated to a single symbol
;; var:: type ; type can be S-expr
;; var ::type ; non standard, but allowed
;;
;; Typed variables usually comes with list, something like this:
;;
;; (a b::<int> c::(<List> <integer>) :optional (d::<int> 3))
;;
;; Canonicalization recognizes variations and produces this:
;;
;; ((a :: default-type)
;; (b :: <int>)
;; (c :: (<List> <integer>))
;; :optional (d :: <int> 3))
;;
;; Each typed variable becomes this form:
;;
;; (varname :: type [init-val] [qual ...])
;;
;; If type is omitted, <top> is assumed for stubs, while ScmObj is
;; assumed for CiSEs, so the default-type is provided by the caller.
;;
;; This is used in muliple places with slightly different requirements.
;;
;; 1. Stubs
;; 1a. Parsing argument list of cproc
;; 1b. Parsing argument list of cmethod
;; 1c. Parsing return value types of them
;;
;; 2. CiSE
;; 1a. Parsing argument list of cfn
;; 1b. Parsing return value types of cfn
;; 1c. Parsing varaible declaration of let*
;; 1d. Parsing struct/union declaration
;;
;; API
;; Take a list, an interpret its head element(s) as typed var.
;;
;; typed-var : (var :: type . rest)
;; | (var:: type . rest)
;; | (var ::type . rest)
;; | (var::type . rest)
;; | (var . rest)
;; | ... (other than above)
;;
;; Returns its canonical form and the rest of the input list.
;; Canonical form may be #f if the tip of the typed-var is
;; not a typed var.
;; This does not deal with ((var::type init) (var2::type2 init)) type list;
;; which is handled by cgen-canonical-typed-var.
(define (cgen-canonical-typed-var-1 typed-var default-type)
(define (var::type? sym)
(and (symbol? sym)
(rxmatch-if (#/^([^:]+)::([^:]+)$/ (symbol->string sym))
[#f V T]
(list (string->symbol V) (string->symbol T))
#f)))
(define (var::? sym)
(and (symbol? sym)
(rxmatch-if (#/^([^:]+)::$/ (symbol->string sym))
[#f V]
(string->symbol V)
#f)))
(define (::type? sym)
(and (keyword? sym)
(rxmatch-if (#/^:([^:]+)$/ (keyword->string sym))
[#f T]
(string->symbol T)
#f)))
(define (var? sym)
(and (symbol? sym)
(not (string-index (symbol->string sym) #\:))))
(match typed-var
[() (values #f '())]
[(head . tail)
(cond [(var::type? head)
=> (^[vt] (values `(,(car vt) :: ,(cadr vt)) tail))]
[(var::? head)
=> (^v (match tail
[(type . tail) (values `(,v :: ,type) tail)]
[_ (error "missing type for " head)]))]
[(keyword? head) (values #f typed-var)]
[(var? head)
(match tail
[() (values `(,head :: ,default-type) tail)]
[(':: type . tail) (values `(,head :: ,type) tail)]
[(maybe-type . tail2)
(cond [(::type? maybe-type)
=> (^t (values `(,head :: ,t) tail2))]
[else (values `(,head :: ,default-type) tail)])])]
[else (values #f typed-var)])])
)
;; API
;; Process entire typed-var-list. This can handle more complex one
;; than cgen-canonical-typed-var-1.
;;
;; typed-var-list : (,@typed-var . typed-var-list)
;; | ((,@typed-var) . typed-var-list)
;; | (:keyword . typed-var-list)
;;
(define (cgen-canonical-typed-var-list typed-var-list default-type)
(define (err decl) (error "invalid variable declaration:" decl))
(define (scan typed-var-list)
(match typed-var-list
[() '()]
[((typed-var ...) . tail)
(receive (var&type opts)
(cgen-canonical-typed-var-1 typed-var default-type)
(if var&type
(cons (append var&type opts) (scan tail))
(err (car opts))))]
[((? keyword? k) . tail) (cons k (scan tail))]
[((? symbol? s) . _)
(receive (var&type tail)
(cgen-canonical-typed-var-1 typed-var-list default-type)
(if var&type
(cons var&type (scan tail))
(err s)))]
[_ (err typed-var-list)]))
(scan typed-var-list))