3 ;;; Code generation protocol implementation
5 ;;; (c) 2009 Straylight/Edgeware
8 ;;;----- Licensing notice ---------------------------------------------------
10 ;;; This file is part of the Sensble Object Design, an object system for C.
12 ;;; SOD is free software; you can redistribute it and/or modify
13 ;;; it under the terms of the GNU General Public License as published by
14 ;;; the Free Software Foundation; either version 2 of the License, or
15 ;;; (at your option) any later version.
17 ;;; SOD is distributed in the hope that it will be useful,
18 ;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
19 ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 ;;; GNU General Public License for more details.
22 ;;; You should have received a copy of the GNU General Public License
23 ;;; along with SOD; if not, write to the Free Software Foundation,
24 ;;; Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
28 ;;;--------------------------------------------------------------------------
31 (export '(temporary-argument temporary-function))
32 (defclass temporary-argument (temporary-name) ())
33 (defclass temporary-function (temporary-name) ())
35 (export 'temporary-variable)
36 (defclass temporary-variable (temporary-name)
37 ((in-use-p :initarg :in-use-p :initform nil
38 :type boolean :accessor var-in-use-p)))
40 (defmethod commentify-argument-name ((name temporary-name))
43 (defun temporary-function ()
44 "Return a temporary function name."
45 (make-instance 'temporary-function
46 :tag (prog1 *temporary-index* (incf *temporary-index*))))
48 (defmethod format-temporary-name ((var temporary-name) stream)
49 (format stream "~A" (temp-tag var)))
50 (defmethod format-temporary-name ((var temporary-argument) stream)
51 (format stream "sod__a~A" (temp-tag var)))
52 (defmethod format-temporary-name ((var temporary-variable) stream)
53 (format stream "sod__v~A" (temp-tag var)))
54 (defmethod format-temporary-name ((var temporary-function) stream)
55 (format stream "sod__f~A" (temp-tag var)))
57 (defmethod print-object ((var temporary-name) stream)
59 (print-unreadable-object (var stream :type t)
60 (prin1 (temp-tag var) stream))
61 (format-temporary-name var stream)))
63 ;;;--------------------------------------------------------------------------
64 ;;; Instruction types.
66 ;; Compound statements.
68 ;; HACK: use gensyms for the `condition' slots to avoid leaking the slot
69 ;; names, since the symbol `condition' actually comes from the `common-lisp'
70 ;; package. The `definst' machinery will symbolicate the various associated
71 ;; methods correctly despite this subterfuge.
73 (definst if (stream :export t) (#1=#:condition consequent alternative)
74 (format-compound-statement (stream consequent alternative)
75 (format stream "if (~A)" #1#))
77 (format-compound-statement (stream alternative)
78 (write-string "else" stream))))
80 (definst while (stream :export t) (#1=#:condition body)
81 (format-compound-statement (stream body)
82 (format stream "while (~A)" #1#)))
84 (definst do-while (stream :export t) (body #1=#:condition)
85 (format-compound-statement (stream body :space)
86 (write-string "do" stream))
87 (format stream "while (~A);" #1#))
89 ;; Special varargs hacks.
91 (definst va-start (stream :export t) (ap arg)
92 (format stream "va_start(~@<~A, ~_~A~:>);" ap arg))
94 (definst va-copy (stream :export t) (to from)
95 (format stream "va_copy(~@<~A, ~_~A~:>);" to from))
97 (definst va-end (stream :export t) (ap)
98 (format stream "va_end(~A);" ap))
102 ;; HACK: use a gensym for the `func' slot to avoid leaking the slot name,
103 ;; since the symbol `func' is exported from our package.
104 (definst call (stream :export t) (#1=#:func args)
105 (format stream "~A(~@<~{~A~^, ~_~}~:>)" #1# args))
107 ;;;--------------------------------------------------------------------------
108 ;;; Code generator objects.
110 (defclass basic-codegen ()
111 ((vars :initarg :vars :initform nil :type list :accessor codegen-vars)
112 (insts :initarg :insts :initform nil :type list :accessor codegen-insts)
113 (temp-index :initarg :temp-index :initform 0
114 :type fixnum :accessor codegen-temp-index))
116 "Base class for code generator state.
118 This contains the bare essentials for supporting the `emit-inst' and
119 `ensure-var' protocols; see the documentation for those generic functions
122 This class isn't abstract. A full `codegen' object uses instances of this
123 to keep track of pending functions which haven't been completed yet.
125 Just in case that wasn't clear enough: this is nothing to do with the
128 (defmethod emit-inst ((codegen basic-codegen) inst)
129 (push inst (codegen-insts codegen)))
131 (defmethod emit-insts ((codegen basic-codegen) insts)
132 (asetf (codegen-insts codegen) (revappend insts it)))
134 (defmethod emit-decl ((codegen basic-codegen) inst)
135 (push inst (codegen-vars codegen)))
137 (defmethod emit-decls ((codegen basic-codegen) insts)
138 (asetf (codegen-vars codegen) (revappend insts it)))
140 (defmethod ensure-var ((codegen basic-codegen) name type &optional init)
141 (let* ((vars (codegen-vars codegen))
143 (remove-if-not (lambda (var) (typep var 'var-inst)) vars)
144 :key #'inst-name :test #'equal)))
146 (setf (codegen-vars codegen)
147 (cons (make-var-inst name type init) vars)))
148 ((not (c-type-equal-p type (inst-type var)))
149 (error "(Internal) Redefining type for variable ~A." name)))
153 (defclass codegen (basic-codegen)
154 ((functions :initform nil :type list :accessor codegen-functions)
155 (stack :initform nil :type list :accessor codegen-stack))
157 "A full-fat code generator which can generate and track functions.
159 This is the real deal. Subclasses may which to attach additional state
160 for convenience's sake, but this class is self-contained. It supports the
161 `codegen-push', `codegen-pop' and `codegen-pop-function' protocols."))
163 (defmethod codegen-push ((codegen codegen))
164 (with-slots (vars insts temp-index stack) codegen
165 (push (make-instance 'basic-codegen
168 :temp-index temp-index)
170 (setf vars nil insts nil temp-index 0)))
172 (defmethod codegen-pop ((codegen codegen))
173 (with-slots (vars insts temp-index stack) codegen
174 (multiple-value-prog1
175 (values (nreverse vars) (nreverse insts))
176 (let ((sub (pop stack)))
177 (setf vars (codegen-vars sub)
178 insts (codegen-insts sub)
179 temp-index (codegen-temp-index sub))))))
181 (defmethod codegen-add-function ((codegen codegen) function)
182 (with-slots (functions) codegen
183 (setf functions (nconc functions (list function)))))
185 (defmethod temporary-var ((codegen basic-codegen) type)
186 (with-slots (vars temp-index) codegen
187 (or (some (lambda (var)
188 (let ((name (inst-name var)))
189 (if (and (not (var-in-use-p name))
190 (c-type-equal-p type (inst-type var)))
193 (remove-if-not (lambda (var) (typep var 'var-inst)) vars))
194 (let* ((name (make-instance 'temporary-variable
196 :tag (prog1 temp-index
197 (incf temp-index)))))
198 (push (make-var-inst name type nil) vars)
201 ;;;----- That's all, folks --------------------------------------------------