| blob | 730a764e026ee36ccdf674109fa4c3966af8993d |
1 ;;;; cross-compiler-only versions of TYPEP, TYPE-OF, and related functions
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.
14 ;;; Is X a fixnum in the target Lisp?
19 ;;; (This was a useful warning when trying to get bootstrapping
20 ;;; to work, but it's mostly irrelevant noise now that the system
21 ;;; works.)
27 ))
30 s
31 "cross-compilation-time type ambiguity (should be OK) in ~S:~%~A"
35 ;;; This warning is issued when giving up on a type calculation where a
36 ;;; conservative answer is acceptable. Since a conservative answer is
37 ;;; acceptable, the only downside is lost optimization opportunities.
42 )))
44 ;;; This warning refers to the flexibility in the ANSI spec with
45 ;;; regard to run-time distinctions between floating point types.
46 ;;; (E.g. the cross-compilation host might not even distinguish
47 ;;; between SINGLE-FLOAT and DOUBLE-FLOAT, so a DOUBLE-FLOAT number
48 ;;; would test positive as SINGLE-FLOAT.) If the target SBCL does make
49 ;;; this distinction, then information is lost. It's not too hard to
50 ;;; contrive situations where this would be a problem. In practice we
51 ;;; don't tend to run into them because all widely used Common Lisp
52 ;;; environments do recognize the distinction between SINGLE-FLOAT and
53 ;;; DOUBLE-FLOAT, and we don't really need the other distinctions
54 ;;; (e.g. between SHORT-FLOAT and SINGLE-FLOAT), so we call
55 ;;; WARN-POSSIBLE-CROSS-TYPE-FLOAT-INFO-LOSS to test at runtime
56 ;;; whether we need to worry about this at all, and not warn unless we
57 ;;; do. If we *do* have to worry about this at runtime, my (WHN
58 ;;; 19990808) guess is that the system will break in multiple places,
59 ;;; so this is a real WARNING, not just a STYLE-WARNING.
60 ;;;
61 ;;; KLUDGE: If we ever try to support LONG-FLOAT or SHORT-FLOAT, this
62 ;;; situation will get a lot more complicated.
74 raw-result)
79 ;; it's a FIXNUM, but instead test against target
80 ;; MOST-fooITIVE-FIXNUM limits.
90 raw-result)
94 ;;; Is SYMBOL in the CL package? Note that we're testing this on the
95 ;;; cross-compilation host, which could do things any old way. In
96 ;;; particular, it might be in the CL package even though
97 ;;; SYMBOL-PACKAGE is not (FIND-PACKAGE :CL). So we test things
98 ;;; another way.
101 symbol))
103 ;;; This is like TYPEP, except that it asks whether HOST-OBJECT would
104 ;;; be of TARGET-TYPE when instantiated on the target SBCL. Since this
105 ;;; is hard to determine in some cases, and since in other cases we
106 ;;; just haven't bothered to try, it needs to return two values, just
107 ;;; like SUBTYPEP: the first value for its conservative opinion (never
108 ;;; T unless it's certain) and the second value to tell whether it's
109 ;;; certain.
113 ;; We don't have to keep track of this as long as system
114 ;; performance is acceptable, since giving up
115 ;; conservatively is a safe way out.
116 #+nil
123 ;; a convenient idiom for making more matches to special cases:
124 ;; Test both forms of target type for membership in LIST.
125 ;;
126 ;; (In order to avoid having to use too much deep knowledge
127 ;; of types, it's sometimes convenient to test RAW-TARGET-TYPE
128 ;; as well as the expanded type, since we can get matches with
129 ;; just EQL. E.g. SIMPLE-STRING can be matched with EQL, while
130 ;; safely matching its expansion,
131 ;; (OR (SIMPLE-ARRAY CHARACTER (*)) (SIMPLE-BASE-STRING *))
132 ;; would require logic clever enough to know that, e.g., OR is
133 ;; commutative.)
138 ;; the ANSI cross-compilation host. KLUDGE: This code will
139 ;; need to be tweaked by hand if the names of these types
140 ;; ever change, ugh!
149 ;; instead a CLASS object.
166 ;; partition, but it includes at least lists and vectors.
186 ;; KLUDGE: SBCL has * as an explicit wild type. While
187 ;; this is sort of logical (because (e.g. (ARRAY * 1)) is
188 ;; a valid type) it's not ANSI: looking at the ANSI
189 ;; definitions of complex types like like ARRAY shows
190 ;; that they consider * different from other type names.
191 ;; Someday we should probably get rid of this non-ANSIism
192 ;; in base SBCL, but until we do, we might as well here
193 ;; in the cross compiler. And in order to make sure that
194 ;; we don't continue doing it after we someday patch
195 ;; SBCL's type system so that * is no longer a type, we
196 ;; make this assertion. -- WHN 2001-08-08
200 ;; between any host ANSI Common Lisp and the target
201 ;; Common Lisp. (Some array types are too, but they
202 ;; were picked off earlier.)
205 list nil null number rational real signed-byte symbol t
206 unsigned-byte))
209 ;; too, but less exactly.
223 ;; Some types require translation between the cross-compilation
224 ;; host Common Lisp and the target SBCL.
229 ;; Some types are too hard to handle in the positive
230 ;; case, but at least we can be confident in a large
231 ;; fraction of the negative cases..
245 ;; Neither target CL:STREAM nor target SB!KERNEL:INSTANCE
246 ;; is implemented as a STRUCTURE-OBJECT, so they'll fall
247 ;; through the tests above. We don't want to assume too
248 ;; much about them here, but at least we know enough
249 ;; about them to say that neither T nor NIL nor indeed
250 ;; any other symbol in the cross-compilation host is one.
251 ;; That knowledge suffices to answer so many of the
252 ;; questions that the cross-compiler asks that it's well
253 ;; worth special-casing it here.
257 ;; various hacks for composite types..
262 ;; Many complex types are guaranteed to correspond exactly
263 ;; between any host ANSI Common Lisp and the target SBCL.
266 ;; Floating point types are guaranteed to correspond,
267 ;; too, but less exactly.
274 ;; Some complex types have translations that are less
275 ;; trivial.
278 ;; If we want to work with the KEYWORD type, we need
279 ;; to grok (SATISFIES KEYWORDP).
284 ;; Many predicates like KEYWORDP, ODDP, PACKAGEP,
285 ;; and NULL correspond between host and target.
286 ;; But we still need to handle errors, because
287 ;; the code which calls us may not understand
288 ;; that a type is unreachable. (E.g. when compiling
289 ;; (AND STRING (SATISFIES ARRAY-HAS-FILL-POINTER-P))
290 ;; CTYPEP may be called on the SATISFIES expression
291 ;; even for non-STRINGs.)
294 host-object))
298 ;; For symbols not in the CL package, it's not
299 ;; in general clear how things correspond
300 ;; between host and target, so we punt.
302 ;; Some complex types are too hard to handle in the
303 ;; positive case, but at least we can be confident in
304 ;; a large fraction of the negative cases..
321 ;; And the Common Lisp type system is complicated,
322 ;; and we don't try to implement everything.
324 ;; And the Common Lisp type system is complicated, and
325 ;; we don't try to implement everything.
329 ;;; This is an incomplete TYPEP which runs at cross-compile time to
330 ;;; tell whether OBJECT is the host Lisp representation of a target
331 ;;; SBCL type specified by TARGET-TYPE-SPEC. It need make no pretense
332 ;;; to completeness, since it need only handle the cases which arise
333 ;;; when building SBCL itself, e.g. testing that range limits FOO and
334 ;;; BAR in (INTEGER FOO BAR) are INTEGERs.
340 ;; A program that calls TYPEP doesn't want uncertainty and
341 ;; probably can't handle it.
343 opinion
345 host-object
346 target-type-spec))))
348 ;;; This is an incomplete, portable implementation for use at
349 ;;; cross-compile time only.
352 ;; There is at least one possible endless recursion in the
353 ;; cross-compiler type system: (SUBTYPEP NULL (OR UNKOWN0 UNKNOWN1)
354 ;; runs out of stack. The right way would probably be to not
355 ;; implement CTYPEP in terms of TYPE-SPECIFIER (:UNPARSE, that may
356 ;; call TYPE=, that in turn may call CTYPEP). Until then, pick a few
357 ;; cherries off.
374 ;; Since at cross-compile time we build a CLOS-free bootstrap
375 ;; version of SBCL, it's unclear how to explain to it what a
376 ;; generic function is.
378 ;; There's no ANSI way to find out what the function is
379 ;; declared to be, so we just return the CTYPE for the
380 ;; most-general function.
395 :element-type etype
400 ;; (Note that SBCL doesn't distinguish between BASE-CHAR and
401 ;; CHARACTER.)
404 nil)
406 ;; Beyond this, there seems to be no portable correspondence.
411 ;; There might be more cases which we could handle with
412 ;; sufficient effort; since all we *need* to handle are enough
413 ;; cases for bootstrapping, we don't try to be complete here,. If
414 ;; future maintainers make the bootstrap code more complicated,
415 ;; they can also add new cases here to handle it. -- WHN 2000-11-11