src/compiler/info-functions.lisp

   1 ;;;; miscellaneous functions which use INFO
   2 ;;;;
   3 ;;;; (In CMU CL, these were in globaldb.lisp. They've been moved here
   4 ;;;; because references to INFO can't be compiled correctly until
   5 ;;;; globaldb initialization is complete, and the SBCL technique for
   6 ;;;; initializing the global database in the cross-compiler isn't
   7 ;;;; completed until load time.)
   8
   9 ;;;; This software is part of the SBCL system. See the README file for
  10 ;;;; more information.
  11 ;;;;
  12 ;;;; This software is derived from the CMU CL system, which was
  13 ;;;; written at Carnegie Mellon University and released into the
  14 ;;;; public domain. The software is in the public domain and is
  15 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
  16 ;;;; files for more information.
  17
  18 (in-package "SB!C")
  19 \f
  20 ;;;; internal utilities defined in terms of INFO
  21
  22 ;;; Check that NAME is a valid function name, returning the name if
  23 ;;; OK, and signalling an error if not. In addition to checking for
  24 ;;; basic well-formedness, we also check that symbol names are not NIL
  25 ;;; or the name of a special form.
  26 (defun check-fun-name (name)
  27   (typecase name
  28     (list
  29      (unless (legal-fun-name-p name)
  30        (compiler-error "illegal function name: ~S" name)))
  31     (symbol
  32      (when (eq (info :function :kind name) :special-form)
  33        (compiler-error "Special form is an illegal function name: ~S" name)))
  34     (t
  35      (compiler-error "illegal function name: ~S" name)))
  36   (values))
  37
  38 ;;; Record a new function definition, and check its legality.
  39 (defun proclaim-as-fun-name (name)
  40
  41   ;; legal name?
  42   (check-fun-name name)
  43
  44   ;; scrubbing old data I: possible collision with old definition
  45   (when (fboundp name)
  46     (ecase (info :function :kind name)
  47       (:function) ; happy case
  48       ((nil)) ; another happy case
  49       (:macro ; maybe-not-so-good case
  50        (compiler-style-warn "~S was previously defined as a macro." name)
  51        (setf (info :function :where-from name) :assumed)
  52        (clear-info :function :macro-function name))))
  53
  54   ;; scrubbing old data II: dangling forward references
  55   ;;
  56   ;; (This could happen if someone executes PROCLAIM FTYPE at
  57   ;; macroexpansion time, which is bad style, or at compile time, e.g.
  58   ;; in EVAL-WHEN (:COMPILE) inside something like DEFSTRUCT, in which
  59   ;; case it's reasonable style. Either way, NAME is no longer a free
  60   ;; function.)
  61   (when (boundp '*free-funs*) ; when compiling
  62     (remhash name *free-funs*))
  63
  64   ;; recording the ordinary case
  65   (setf (info :function :kind name) :function)
  66   (note-if-setf-fun-and-macro name)
  67
  68   (values))
  69
  70 ;;; This is called to do something about SETF functions that overlap
  71 ;;; with SETF macros. Perhaps we should interact with the user to see
  72 ;;; whether the macro should be blown away, but for now just give a
  73 ;;; warning. Due to the weak semantics of the (SETF FUNCTION) name, we
  74 ;;; can't assume that they aren't just naming a function (SETF FOO)
  75 ;;; for the heck of it. NAME is already known to be well-formed.
  76 (defun note-if-setf-fun-and-macro (name)
  77   (when (consp name)
  78     (when (or (info :setf :inverse name)
  79               (info :setf :expander name))
  80       (compiler-style-warn
  81        "defining as a SETF function a name that already has a SETF macro:~
  82        ~%  ~S"
  83        name)))
  84   (values))
  85
  86 ;;; Make NAME no longer be a function name: clear everything back to
  87 ;;; the default.
  88 (defun undefine-fun-name (name)
  89   (when name
  90     (macrolet ((frob (type &optional val)
  91                  `(unless (eq (info :function ,type name) ,val)
  92                     (setf (info :function ,type name) ,val))))
  93       (frob :info)
  94       (frob :type (specifier-type 'function))
  95       (frob :where-from :assumed)
  96       (frob :inlinep)
  97       (frob :kind)
  98       (frob :inline-expansion-designator)
  99       (frob :source-transform)
 100       (frob :structure-accessor)
 101       (frob :assumed-type)))
 102   (values))
 103
 104 ;;; part of what happens with DEFUN, also with some PCL stuff: Make
 105 ;;; NAME known to be a function definition.
 106 (defun become-defined-fun-name (name)
 107   (proclaim-as-fun-name name)
 108   (when (eq (info :function :where-from name) :assumed)
 109     (setf (info :function :where-from name) :defined)
 110     (if (info :function :assumed-type name)
 111         (setf (info :function :assumed-type name) nil))))
 112
 113 ;;; Decode any raw (INFO :FUNCTION :INLINE-EXPANSION-DESIGNATOR FUN-NAME)
 114 ;;; value into a lambda expression, or return NIL if there is none.
 115 (declaim (ftype (function ((or symbol cons)) list) fun-name-inline-expansion))
 116 (defun fun-name-inline-expansion (fun-name)
 117   (let ((info (info :function :inline-expansion-designator fun-name)))
 118     (if (functionp info)
 119         (funcall info)
 120         info)))
 121 \f
 122 ;;;; ANSI Common Lisp functions which are defined in terms of the info
 123 ;;;; database
 124
 125 (defun sb!xc:macro-function (symbol &optional env)
 126   #!+sb-doc
 127   "If SYMBOL names a macro in ENV, returns the expansion function,
 128 else returns NIL. If ENV is unspecified or NIL, use the global environment
 129 only."
 130   (declare (symbol symbol))
 131   (let* ((fenv (when env (lexenv-funs env)))
 132          (local-def (cdr (assoc symbol fenv))))
 133     (cond (local-def
 134            (if (and (consp local-def) (eq (car local-def) 'macro))
 135                (cdr local-def)
 136                nil))
 137           ((eq (info :function :kind symbol) :macro)
 138            (values (info :function :macro-function symbol)))
 139           (t
 140            nil))))
 141
 142 (defun (setf sb!xc:macro-function) (function symbol &optional environment)
 143   (declare (symbol symbol) (type function function))
 144   (when environment
 145     ;; Note: Technically there could be an ENV optional argument to SETF
 146     ;; MACRO-FUNCTION, but since ANSI says that the consequences of
 147     ;; supplying a non-nil one are undefined, we don't allow it.
 148     ;; (Thus our implementation of this unspecified behavior is to
 149     ;; complain. SInce the behavior is unspecified, this is conforming.:-)
 150     (error "Non-NIL environment argument in SETF of MACRO-FUNCTION ~S: ~S"
 151            symbol environment))
 152   (when (eq (info :function :kind symbol) :special-form)
 153     (error "~S names a special form." symbol))
 154   (setf (info :function :kind symbol) :macro)
 155   (setf (info :function :macro-function symbol) function)
 156   ;; This is a nice thing to have in the target SBCL, but in the
 157   ;; cross-compilation host it's not nice to mess with
 158   ;; (SYMBOL-FUNCTION FOO) where FOO might be a symbol in the
 159   ;; cross-compilation host's COMMON-LISP package.
 160   #-sb-xc-host
 161   (setf (symbol-function symbol)
 162         (lambda (&rest args)
 163           (declare (ignore args))
 164           ;; (ANSI specification of FUNCALL says that this should be
 165           ;; an error of type UNDEFINED-FUNCTION, not just SIMPLE-ERROR.)
 166           (error 'undefined-function :name symbol)))
 167   function)
 168
 169 (defun fun-locally-defined-p (name env)
 170   (and env
 171        (let ((fun (cdr (assoc name (lexenv-funs env) :test #'equal))))
 172          (and fun (not (global-var-p fun))))))
 173
 174 (defun sb!xc:compiler-macro-function (name &optional env)
 175   #!+sb-doc
 176   "If NAME names a compiler-macro in ENV, return the expansion function, else
 177 return NIL. Can be set with SETF when ENV is NIL."
 178   (legal-fun-name-or-type-error name)
 179   ;; CLHS 3.2.2.1: Creating a lexical binding for the function name
 180   ;; not only creates a new local function or macro definition, but
 181   ;; also shadows[2] the compiler macro.
 182   (unless (fun-locally-defined-p name env)
 183     ;; Note: CMU CL used to return NIL here when a NOTINLINE
 184     ;; declaration was in force. That's fairly logical, given the
 185     ;; specified effect of NOTINLINE declarations on compiler-macro
 186     ;; expansion. However, (1) it doesn't seem to be consistent with
 187     ;; the ANSI spec for COMPILER-MACRO-FUNCTION, and (2) it would
 188     ;; give surprising behavior for (SETF (COMPILER-MACRO-FUNCTION
 189     ;; FOO) ...) in the presence of a (PROCLAIM '(NOTINLINE FOO)). So
 190     ;; we don't do it.
 191     (values (info :function :compiler-macro-function name))))
 192
 193 (defun (setf sb!xc:compiler-macro-function) (function name &optional env)
 194   (declare (type (or symbol list) name)
 195            (type (or function null) function))
 196   (when env
 197     ;; ANSI says this operation is undefined.
 198     (error "can't SETF COMPILER-MACRO-FUNCTION when ENV is non-NIL"))
 199   (when (eq (info :function :kind name) :special-form)
 200     (error "~S names a special form." name))
 201   (with-single-package-locked-error
 202       (:symbol name "setting the compiler-macro-function of ~A")
 203     (setf (info :function :compiler-macro-function name) function)
 204     function))
 205 \f
 206 ;;;; a subset of DOCUMENTATION functionality for bootstrapping
 207
 208 ;;; FDOCUMENTATION is like DOCUMENTATION, but with less functionality,
 209 ;;; and implemented with DEFUN instead of DEFGENERIC so that it can
 210 ;;; run before CLOS is set up. Supported DOC-TYPE values are
 211 ;;;   FUNCTION
 212 ;;;   SETF
 213 ;;;   STRUCTURE
 214 ;;;   T
 215 ;;;   TYPE
 216 ;;;   VARIABLE
 217 ;;; FIXME: Other types end up in INFO :RANDOM-DOCUMENTATION :STUFF. I
 218 ;;; should add some code to monitor this and make sure that nothing is
 219 ;;; unintentionally being sent to never never land this way.
 220 ;;; FIXME: Rename FDOCUMENTATION to BDOCUMENTATION, by analogy with
 221 ;;; DEF!STRUCT and DEF!MACRO and so forth. And consider simply saving
 222 ;;; all the BDOCUMENTATION entries in a *BDOCUMENTATION* hash table
 223 ;;; and slamming them into PCL once PCL gets going.
 224 (defun fdocumentation (x doc-type)
 225   (case doc-type
 226     (variable
 227      (typecase x
 228        (symbol (values (info :variable :documentation x)))))
 229     ;; FUNCTION is not used at the momemnt, just here for symmetry.
 230     (function
 231      (cond ((functionp x)
 232             (%fun-doc x))
 233            ((and (legal-fun-name-p x) (fboundp x))
 234             (%fun-doc (or (and (symbolp x) (macro-function x))
 235                           (fdefinition x))))))
 236     (structure
 237      (typecase x
 238        (symbol (cond
 239                  ((eq (info :type :kind x) :instance)
 240                   (values (info :type :documentation x)))
 241                  ((info :typed-structure :info x)
 242                   (values (info :typed-structure :documentation x)))))))
 243     (type
 244      (typecase x
 245        (structure-class (values (info :type :documentation (class-name x))))
 246        (t (and (typep x 'symbol) (values (info :type :documentation x))))))
 247     (setf (values (info :setf :documentation x)))
 248     ((t)
 249      (typecase x
 250        (function (%fun-doc x))
 251        (package (package-doc-string x))
 252        (structure-class (values (info :type :documentation (class-name x))))
 253        ((or symbol cons)
 254         (random-documentation x doc-type))))
 255     (t
 256      (when (typep x '(or symbol cons))
 257        (random-documentation x doc-type)))))
 258
 259 (defun (setf fdocumentation) (string name doc-type)
 260   (declare (type (or null string) string))
 261   (case doc-type
 262     (variable (setf (info :variable :documentation name) string))
 263     (function
 264      ;; KLUDGE: FDEFINITION isn't ready early enough during cold-init, so
 265      ;; special case for symbols.
 266      (if (symbolp name)
 267          (setf (%fun-doc (symbol-function name)) string)
 268          (when (legal-fun-name-p name)
 269            (setf (%fun-doc (fdefinition name)) string))))
 270     (structure (cond
 271                  ((eq (info :type :kind name) :instance)
 272                   (setf (info :type :documentation name) string))
 273                  ((info :typed-structure :info name)
 274                   (setf (info :typed-structure :documentation name) string))))
 275     (type (setf (info :type :documentation name) string))
 276     (setf (setf (info :setf :documentation name) string))
 277     (t
 278      (when (typep name '(or symbol cons))
 279        (setf (random-documentation name doc-type) string))))
 280   string)
 281
 282 (defun random-documentation (name type)
 283   (cdr (assoc type (info :random-documentation :stuff name))))
 284
 285 (defun (setf random-documentation) (new-value name type)
 286   (let ((pair (assoc type (info :random-documentation :stuff name))))
 287     (if pair
 288         (setf (cdr pair) new-value)
 289         (push (cons type new-value)
 290               (info :random-documentation :stuff name))))
 291   new-value)