src/compiler/xref.lisp

   1 ;;;; xref facility
   2
   3 ;;;; This software is part of the SBCL system. See the README file for
   4 ;;;; more information.
   5 ;;;;
   6 ;;;; This software is derived from the CMU CL system, which was
   7 ;;;; written at Carnegie Mellon University and released into the
   8 ;;;; public domain. The software is in the public domain and is
   9 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
  10 ;;;; files for more information.
  11
  12 (in-package "SB!C")
  13
  14 (defvar *xref-kinds* '(:binds :calls :sets :references :macroexpands))
  15
  16 (defun record-component-xrefs (component)
  17   (declare (type component component))
  18   (when (policy *lexenv* (zerop store-xref-data))
  19     (return-from record-component-xrefs))
  20   (do ((block (block-next (component-head component)) (block-next block)))
  21       ((null (block-next block)))
  22     (let ((start (block-start block)))
  23       (flet ((handle-node (functional)
  24                ;; Record xref information for all nodes in the block.
  25                ;; Note that this code can get executed several times
  26                ;; for the same block, if the functional is referenced
  27                ;; from multiple XEPs.
  28                (loop for ctran = start then (node-next (ctran-next ctran))
  29                      while ctran
  30                      do (record-node-xrefs (ctran-next ctran) functional))
  31                ;; Properly record the deferred macroexpansion information
  32                ;; that's been stored in the block.
  33                (dolist (xref-data (block-macroexpands block))
  34                  (record-xref :macroexpands
  35                               (car xref-data)
  36                               ;; We use the debug-name of the functional
  37                               ;; as an identifier. This works quite nicely,
  38                               ;; except for (fast/slow)-methods with non-symbol,
  39                               ;; non-number eql specializers, for which
  40                               ;; the debug-name doesn't map exactly
  41                               ;; to the fdefinition of the method.
  42                               functional
  43                               nil
  44                               (cdr xref-data)))))
  45         (call-with-block-external-functionals block #'handle-node)))))
  46
  47 (defun call-with-block-external-functionals (block fun)
  48   (let* ((functional (block-home-lambda block))
  49          (seen nil))
  50     (labels ((local-function-name-p (name)
  51                (and (consp name)
  52                     (member (car name)
  53                             '(flet labels lambda))))
  54              (handle-functional (functional)
  55                ;; If a functional looks like a global function (has a
  56                ;; XEP, isn't a local function or a lambda) record xref
  57                ;; information for it. Otherwise recurse on the
  58                ;; home-lambdas of all references to the functional.
  59                (when (eq (functional-kind functional) :external)
  60                  (let ((entry (functional-entry-fun functional)))
  61                    (when entry
  62                      (let ((name (functional-debug-name entry)))
  63                        (unless (local-function-name-p name)
  64                          (return-from handle-functional
  65                            (funcall fun entry)))))))
  66                ;; Recurse only if we haven't already seen the
  67                ;; functional.
  68                (unless (member functional seen)
  69                  (push functional seen)
  70                  (dolist (ref (functional-refs functional))
  71                    (handle-functional (node-home-lambda ref))))))
  72       (unless (or (eq :deleted (functional-kind functional))
  73                   ;; If the block came from an inlined global
  74                   ;; function, ignore it.
  75                   (and (functional-inlinep functional)
  76                        (symbolp (functional-debug-name functional))))
  77         (handle-functional functional)))))
  78
  79 (defun record-node-xrefs (node context)
  80   (declare (type node node))
  81   (etypecase node
  82     ((or creturn cif entry mv-combination cast exit))
  83     (combination
  84      ;; Record references to globals made using SYMBOL-VALUE.
  85      (let ((fun (principal-lvar-use (combination-fun node)))
  86            (arg (car (combination-args node))))
  87        (when (and (ref-p fun) (eq 'symbol-value (leaf-%source-name (ref-leaf fun)))
  88                   (constant-lvar-p arg) (symbolp (lvar-value arg)))
  89          (record-xref :references (lvar-value arg) context node nil))))
  90     (ref
  91      (let ((leaf (ref-leaf node)))
  92        (typecase leaf
  93          (global-var
  94           (let* ((name (leaf-debug-name leaf)))
  95             (case (global-var-kind leaf)
  96               ;; Reading a special
  97               (:special
  98                (record-xref :references name context node nil))
  99               ;; Calling a function
 100               (:global-function
 101                (record-xref :calls name context node nil)))))
 102          ;; Inlined global function
 103          (clambda
 104           (when (functional-inlinep leaf)
 105             (let ((name (leaf-debug-name leaf)))
 106               ;; FIXME: we should store the original var into the
 107               ;; functional when creating inlined-functionals, so that
 108               ;; we could just check whether it was a global-var,
 109               ;; rather then needing to guess based on the debug-name.
 110               (when (or (symbolp name)
 111                         ;; Any non-SETF non-symbol names will
 112                         ;; currently be either non-functions or
 113                         ;; internals.
 114                         (and (consp name)
 115                              (equal (car name) 'setf)))
 116                 ;; TODO: a WHO-INLINES xref-kind could be useful
 117                 (record-xref :calls name context node nil)))))
 118          ;; Reading a constant
 119          (constant
 120           (record-xref :references (ref-%source-name node) context node nil)))))
 121     ;; Setting a special variable
 122     (cset
 123      (let* ((var (set-var node)))
 124        (when (and (global-var-p var)
 125                   (eq :special (global-var-kind var)))
 126          (record-xref :sets
 127                       (leaf-debug-name var)
 128                       context
 129                       node
 130                       nil))))
 131     ;; Binding a special variable
 132     (bind
 133      (let ((vars (lambda-vars (bind-lambda node))))
 134        (dolist (var vars)
 135          (when (lambda-var-specvar var)
 136            (record-xref :binds
 137                         (lambda-var-%source-name var)
 138                         context
 139                         node
 140                         nil)))))))
 141
 142 (defun internal-name-p (what)
 143   ;; Don't store XREF information for internals. We define as internal
 144   ;; anything named only by symbols from either implementation
 145   ;; packages, COMMON-LISP or KEYWORD. The last one is useful for
 146   ;; example when dealing with ctors.
 147   (typecase what
 148     (list
 149      (every #'internal-name-p what))
 150     (symbol
 151      (or (eq '.anonymous. what)
 152          (member (symbol-package what)
 153                  (load-time-value (list* (find-package "COMMON-LISP")
 154                                          (find-package "KEYWORD")
 155                                          (remove-if-not
 156                                           (lambda (package)
 157                                             (= (mismatch "SB!"
 158                                                          (package-name package))
 159                                                3))
 160                                           (list-all-packages)))))))
 161     (t t)))
 162
 163 (defun record-xref (kind what context node path)
 164   (unless (internal-name-p what)
 165     (let ((path (reverse
 166                  (source-path-original-source
 167                   (or path
 168                       (node-source-path node))))))
 169       (push (list what path)
 170             (getf (functional-xref context) kind)))))
 171
 172 (defun record-macroexpansion (what block path)
 173   (unless (internal-name-p what)
 174     (push (cons what path) (block-macroexpands block))))
 175
 176 ;;; Pack the xref table that was stored for a functional into a more
 177 ;;; space-efficient form, and return that packed form.
 178 (defun pack-xref-data (xref-data)
 179   (when xref-data
 180     (let ((array (make-array (length *xref-kinds*))))
 181       (loop for key in *xref-kinds*
 182             for i from 0
 183             for values = (remove-duplicates (getf xref-data key)
 184                                             :test #'equal)
 185             for flattened = (reduce #'append values :from-end t)
 186             collect (setf (aref array i)
 187                           (when flattened
 188                             (make-array (length flattened)
 189                                         :initial-contents flattened))))
 190       array)))