1 ;;;; type testing and checking VOPs for the x86-64 VM
3 ;;;; This software is part of the SBCL system. See the README file for
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 ;;;; test generation utilities
16 (defun generate-fixnum-test (value)
17 "zero flag set if VALUE is fixnum"
19 (cond ((sc-is value any-reg descriptor-reg)
21 ((sc-is value control-stack)
22 (make-ea :byte :base rbp-tn
23 :disp (frame-byte-offset (tn-offset value))))
26 sb!vm::fixnum-tag-mask))
28 (defun %test-fixnum (value target not-p)
29 (generate-fixnum-test value)
30 (inst jmp (if not-p :nz :z) target))
32 (defun %test-fixnum-and-headers (value target not-p headers)
33 (let ((drop-through (gen-label)))
34 (generate-fixnum-test value)
35 (inst jmp :z (if not-p drop-through target))
36 (%test-headers value target not-p nil headers drop-through)))
38 (defun %test-fixnum-and-immediate (value target not-p immediate)
39 (let ((drop-through (gen-label)))
40 (generate-fixnum-test value)
41 (inst jmp :z (if not-p drop-through target))
42 (%test-immediate value target not-p immediate drop-through)))
44 (defun %test-fixnum-immediate-and-headers (value target not-p immediate
46 (let ((drop-through (gen-label)))
47 (generate-fixnum-test value)
48 (inst jmp :z (if not-p drop-through target))
49 (%test-immediate-and-headers value target not-p immediate headers
52 (defun %test-immediate (value target not-p immediate
53 &optional (drop-through (gen-label)))
54 ;; Code a single instruction byte test if possible.
55 (cond ((sc-is value any-reg descriptor-reg)
56 (inst cmp (make-byte-tn value) immediate))
59 (inst cmp al-tn immediate)))
60 (inst jmp (if not-p :ne :e) target)
61 (emit-label drop-through))
63 (defun %test-immediate-and-headers (value target not-p immediate headers
64 &optional (drop-through (gen-label)))
65 ;; Code a single instruction byte test if possible.
66 (cond ((sc-is value any-reg descriptor-reg)
67 (inst cmp (make-byte-tn value) immediate))
70 (inst cmp al-tn immediate)))
71 (inst jmp :e (if not-p drop-through target))
72 (%test-headers value target not-p nil headers drop-through))
74 (defun %test-lowtag (value target not-p lowtag)
75 (if (and (sc-is value any-reg descriptor-reg)
76 (< (tn-offset value) r8-offset))
77 (move eax-tn (make-dword-tn value)) ; shorter encoding (no REX prefix)
79 (inst and al-tn lowtag-mask)
80 (inst cmp al-tn lowtag)
81 (inst jmp (if not-p :ne :e) target))
83 (defun %test-headers (value target not-p function-p headers
84 &optional (drop-through (gen-label)))
85 (let ((lowtag (if function-p fun-pointer-lowtag other-pointer-lowtag)))
86 (multiple-value-bind (equal less-or-equal when-true when-false)
87 ;; EQUAL and LESS-OR-EQUAL are the conditions for branching to TARGET.
88 ;; WHEN-TRUE and WHEN-FALSE are the labels to branch to when we know
89 ;; it's true and when we know it's false respectively.
91 (values :ne :a drop-through target)
92 (values :e :na target drop-through))
93 (%test-lowtag value when-false t lowtag)
94 (inst mov al-tn (make-ea :byte :base value :disp (- lowtag)))
95 (do ((remaining headers (cdr remaining)))
97 (let ((header (car remaining))
98 (last (null (cdr remaining))))
101 (inst cmp al-tn header)
103 (inst jmp equal target)
104 (inst jmp :e when-true)))
106 (let ((start (car header))
108 (unless (= start bignum-widetag)
109 (inst cmp al-tn start)
110 (inst jmp :b when-false)) ; was :l
113 (inst jmp less-or-equal target)
114 (inst jmp :be when-true))))))) ; was :le
115 (emit-label drop-through))))
118 ;;;; type checking and testing
120 (define-vop (check-type)
121 (:args (value :target result :scs (any-reg descriptor-reg)))
122 (:results (result :scs (any-reg descriptor-reg)))
123 (:temporary (:sc unsigned-reg :offset eax-offset :to (:result 0)) eax)
126 (:save-p :compute-only))
128 (define-vop (type-predicate)
129 (:args (value :scs (any-reg descriptor-reg)))
130 (:temporary (:sc unsigned-reg :offset eax-offset) eax)
134 (:policy :fast-safe))
136 ;;; simpler VOP that don't need a temporary register
137 (define-vop (simple-check-type)
138 (:args (value :target result :scs (any-reg descriptor-reg)))
139 (:results (result :scs (any-reg descriptor-reg)
140 :load-if (not (and (sc-is value any-reg descriptor-reg)
141 (sc-is result control-stack)))))
143 (:save-p :compute-only))
145 (define-vop (simple-type-predicate)
146 (:args (value :scs (any-reg descriptor-reg control-stack)))
149 (:policy :fast-safe))
151 (defun cost-to-test-types (type-codes)
152 (+ (* 2 (length type-codes))
153 (if (> (apply #'max type-codes) lowtag-limit) 7 2)))
155 (defmacro !define-type-vops (pred-name check-name ptype error-code
157 &key (variant nil variant-p) &allow-other-keys)
158 ;; KLUDGE: UGH. Why do we need this eval? Can't we put this in the
160 (let* ((cost (cost-to-test-types (mapcar #'eval type-codes)))
161 (prefix (if variant-p
162 (concatenate 'string (string variant) "-")
166 `((define-vop (,pred-name ,(intern (concatenate 'string prefix "TYPE-PREDICATE")))
167 (:translate ,pred-name)
169 (test-type value target not-p (,@type-codes))))))
171 `((define-vop (,check-name ,(intern (concatenate 'string prefix "CHECK-TYPE")))
174 (generate-error-code vop ',error-code value)))
175 (test-type value err-lab t (,@type-codes))
176 (move result value))))))
178 `((primitive-type-vop ,check-name (:check) ,ptype))))))
180 ;;;; other integer ranges
182 (define-vop (fixnump/unsigned-byte-64 simple-type-predicate)
183 (:args (value :scs (unsigned-reg)))
184 (:arg-types unsigned-num)
186 (:temporary (:sc unsigned-reg) tmp)
191 (inst shr tmp n-positive-fixnum-bits)))
193 (define-vop (fixnump/signed-byte-64 type-predicate)
194 (:args (value :scs (signed-reg)))
197 (:arg-types signed-num)
200 ;; Hackers Delight, p. 53: signed
201 ;; a <= x <= a + 2^n - 1
202 ;; is equivalent to unsigned
204 (inst mov rax-tn #.(- sb!xc:most-negative-fixnum))
205 (inst add rax-tn value)
206 (inst shr rax-tn #.(integer-length (- sb!xc:most-positive-fixnum
207 sb!xc:most-negative-fixnum)))))
209 ;;; A (SIGNED-BYTE 64) can be represented with either fixnum or a bignum with
210 ;;; exactly one digit.
212 (define-vop (signed-byte-64-p type-predicate)
213 (:translate signed-byte-64-p)
215 (multiple-value-bind (yep nope)
217 (values not-target target)
218 (values target not-target))
219 (generate-fixnum-test value)
222 (inst and al-tn lowtag-mask)
223 (inst cmp al-tn other-pointer-lowtag)
225 (loadw rax-tn value 0 other-pointer-lowtag)
226 (inst cmp rax-tn (+ (ash 1 n-widetag-bits) bignum-widetag))
227 (inst jmp (if not-p :ne :e) target))
230 (define-vop (check-signed-byte-64 check-type)
232 (let ((nope (generate-error-code vop
233 'object-not-signed-byte-64-error
235 (generate-fixnum-test value)
238 (inst and al-tn lowtag-mask)
239 (inst cmp al-tn other-pointer-lowtag)
241 (loadw rax-tn value 0 other-pointer-lowtag)
242 (inst cmp rax-tn (+ (ash 1 n-widetag-bits) bignum-widetag))
245 (move result value)))
247 ;;; An (unsigned-byte 64) can be represented with either a positive
248 ;;; fixnum, a bignum with exactly one positive digit, or a bignum with
249 ;;; exactly two digits and the second digit all zeros.
250 (define-vop (unsigned-byte-64-p type-predicate)
251 (:translate unsigned-byte-64-p)
253 (let ((not-target (gen-label))
254 (single-word (gen-label))
255 (fixnum (gen-label)))
256 (multiple-value-bind (yep nope)
258 (values not-target target)
259 (values target not-target))
261 (generate-fixnum-test value)
265 ;; If not, is it an other pointer?
266 (inst and rax-tn lowtag-mask)
267 (inst cmp rax-tn other-pointer-lowtag)
270 (loadw rax-tn value 0 other-pointer-lowtag)
272 (inst cmp rax-tn (+ (ash 1 n-widetag-bits) bignum-widetag))
273 (inst jmp :e single-word)
274 ;; If it's other than two, we can't be an (unsigned-byte 64)
275 (inst cmp rax-tn (+ (ash 2 n-widetag-bits) bignum-widetag))
277 ;; Get the second digit.
278 (loadw rax-tn value (1+ bignum-digits-offset) other-pointer-lowtag)
279 ;; All zeros, its an (unsigned-byte 64).
280 (inst or rax-tn rax-tn)
284 (emit-label single-word)
285 ;; Get the single digit.
286 (loadw rax-tn value bignum-digits-offset other-pointer-lowtag)
288 ;; positive implies (unsigned-byte 64).
290 (inst or rax-tn rax-tn)
291 (inst jmp (if not-p :s :ns) target)
293 (emit-label not-target)))))
295 (define-vop (check-unsigned-byte-64 check-type)
298 (generate-error-code vop 'object-not-unsigned-byte-64-error value))
301 (single-word (gen-label)))
304 (generate-fixnum-test value)
308 ;; If not, is it an other pointer?
309 (inst and rax-tn lowtag-mask)
310 (inst cmp rax-tn other-pointer-lowtag)
313 (loadw rax-tn value 0 other-pointer-lowtag)
315 (inst cmp rax-tn (+ (ash 1 n-widetag-bits) bignum-widetag))
316 (inst jmp :e single-word)
317 ;; If it's other than two, we can't be an (unsigned-byte 64)
318 (inst cmp rax-tn (+ (ash 2 n-widetag-bits) bignum-widetag))
320 ;; Get the second digit.
321 (loadw rax-tn value (1+ bignum-digits-offset) other-pointer-lowtag)
322 ;; All zeros, its an (unsigned-byte 64).
323 (inst or rax-tn rax-tn)
327 (emit-label single-word)
328 ;; Get the single digit.
329 (loadw rax-tn value bignum-digits-offset other-pointer-lowtag)
331 ;; positive implies (unsigned-byte 64).
333 (inst or rax-tn rax-tn)
337 (move result value))))
339 ;;;; list/symbol types
341 ;;; symbolp (or symbol (eq nil))
342 ;;; consp (and list (not (eq nil)))
344 (define-vop (symbolp type-predicate)
347 (let ((is-symbol-label (if not-p DROP-THRU target)))
348 (inst cmp value nil-value)
349 (inst jmp :e is-symbol-label)
350 (test-type value target not-p (symbol-header-widetag)))
353 (define-vop (check-symbol check-type)
355 (let ((error (generate-error-code vop 'object-not-symbol-error value)))
356 (inst cmp value nil-value)
357 (inst jmp :e DROP-THRU)
358 (test-type value error t (symbol-header-widetag)))
360 (move result value)))
362 (define-vop (consp type-predicate)
365 (let ((is-not-cons-label (if not-p target DROP-THRU)))
366 (inst cmp value nil-value)
367 (inst jmp :e is-not-cons-label)
368 (test-type value target not-p (list-pointer-lowtag)))
371 (define-vop (check-cons check-type)
373 (let ((error (generate-error-code vop 'object-not-cons-error value)))
374 (inst cmp value nil-value)
376 (test-type value error t (list-pointer-lowtag))
377 (move result value))))