1 ;;;; various primitive memory access VOPs for the x86 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 ;;;; data object ref/set stuff
17 (:args (object :scs (descriptor-reg)))
18 (:info name offset lowtag)
20 (:results (result :scs (descriptor-reg any-reg)))
22 (loadw result object offset lowtag)))
24 (define-vop (set-slot)
25 (:args (object :scs (descriptor-reg))
26 (value :scs (descriptor-reg any-reg immediate)))
27 (:info name offset lowtag)
31 (storew (encode-value-if-immediate value) object offset lowtag)))
35 ;;;; symbol hacking VOPs
37 ;;; these next two cf the sparc version, by jrd.
38 ;;; FIXME: Deref this ^ reference.
41 ;;; The compiler likes to be able to directly SET symbols.
44 (:args (symbol :scs (descriptor-reg))
45 (value :scs (descriptor-reg any-reg)))
46 (:temporary (:sc descriptor-reg) tls)
47 ;;(:policy :fast-safe)
49 (let ((global-val (gen-label))
51 (loadw tls symbol symbol-tls-index-slot other-pointer-lowtag)
53 (inst jmp :z global-val)
54 (inst fs-segment-prefix)
55 (inst cmp (make-ea :dword :base tls) no-tls-value-marker-widetag)
56 (inst jmp :z global-val)
57 (inst fs-segment-prefix)
58 (inst mov (make-ea :dword :base tls) value)
60 (emit-label global-val)
61 (storew value symbol symbol-value-slot other-pointer-lowtag)
64 ;; unithreaded it's a lot simpler ...
66 (define-vop (set cell-set)
67 (:variant symbol-value-slot other-pointer-lowtag))
69 ;;; With Symbol-Value, we check that the value isn't the trap object. So
70 ;;; Symbol-Value of NIL is NIL.
72 (define-vop (symbol-value)
73 (:translate symbol-value)
75 (:args (object :scs (descriptor-reg) :to (:result 1)))
76 (:results (value :scs (descriptor-reg any-reg)))
78 (:save-p :compute-only)
80 (let* ((check-unbound-label (gen-label))
81 (err-lab (generate-error-code vop unbound-symbol-error object))
82 (ret-lab (gen-label)))
83 (loadw value object symbol-tls-index-slot other-pointer-lowtag)
84 (inst fs-segment-prefix)
85 (inst mov value (make-ea :dword :base value))
86 (inst cmp value no-tls-value-marker-widetag)
87 (inst jmp :ne check-unbound-label)
88 (loadw value object symbol-value-slot other-pointer-lowtag)
89 (emit-label check-unbound-label)
90 (inst cmp value unbound-marker-widetag)
92 (emit-label ret-lab))))
95 (define-vop (fast-symbol-value symbol-value)
96 ;; KLUDGE: not really fast, in fact, because we're going to have to
97 ;; do a full lookup of the thread-local area anyway. But half of
98 ;; the meaning of FAST-SYMBOL-VALUE is "do not signal an error if
99 ;; unbound", which is used in the implementation of COPY-SYMBOL. --
102 (:translate symbol-value)
104 (let ((ret-lab (gen-label)))
105 (loadw value object symbol-tls-index-slot other-pointer-lowtag)
106 (inst fs-segment-prefix)
107 (inst mov value (make-ea :dword :base value))
108 (inst cmp value no-tls-value-marker-widetag)
109 (inst jmp :ne ret-lab)
110 (loadw value object symbol-value-slot other-pointer-lowtag)
111 (emit-label ret-lab))))
114 (define-vop (symbol-value)
115 (:translate symbol-value)
117 (:args (object :scs (descriptor-reg) :to (:result 1)))
118 (:results (value :scs (descriptor-reg any-reg)))
120 (:save-p :compute-only)
122 (let ((err-lab (generate-error-code vop unbound-symbol-error object)))
123 (loadw value object symbol-value-slot other-pointer-lowtag)
124 (inst cmp value unbound-marker-widetag)
125 (inst jmp :e err-lab))))
128 (define-vop (fast-symbol-value cell-ref)
129 (:variant symbol-value-slot other-pointer-lowtag)
131 (:translate symbol-value))
133 (defknown locked-symbol-global-value-add (symbol fixnum) fixnum ())
135 (define-vop (locked-symbol-global-value-add)
136 (:args (object :scs (descriptor-reg) :to :result)
137 (value :scs (any-reg) :target result))
138 (:arg-types * tagged-num)
139 (:results (result :scs (any-reg) :from (:argument 1)))
141 (:translate locked-symbol-global-value-add)
142 (:result-types tagged-num)
147 (inst add (make-ea-for-object-slot object symbol-value-slot
148 other-pointer-lowtag)
155 (:args (object :scs (descriptor-reg)))
158 (:temporary (:sc descriptor-reg #+nil(:from (:argument 0))) value)
160 (let ((check-unbound-label (gen-label)))
161 (loadw value object symbol-tls-index-slot other-pointer-lowtag)
162 (inst fs-segment-prefix)
163 (inst mov value (make-ea :dword :base value))
164 (inst cmp value no-tls-value-marker-widetag)
165 (inst jmp :ne check-unbound-label)
166 (loadw value object symbol-value-slot other-pointer-lowtag)
167 (emit-label check-unbound-label)
168 (inst cmp value unbound-marker-widetag)
169 (inst jmp (if not-p :e :ne) target))))
175 (:args (object :scs (descriptor-reg)))
179 (inst cmp (make-ea-for-object-slot object symbol-value-slot
180 other-pointer-lowtag)
181 unbound-marker-widetag)
182 (inst jmp (if not-p :e :ne) target)))
185 (define-vop (symbol-hash)
187 (:translate symbol-hash)
188 (:args (symbol :scs (descriptor-reg)))
189 (:results (res :scs (any-reg)))
190 (:result-types positive-fixnum)
192 ;; The symbol-hash slot of NIL holds NIL because it is also the
193 ;; cdr slot, so we have to strip off the two low bits to make sure
194 ;; it is a fixnum. The lowtag selection magic that is required to
195 ;; ensure this is explained in the comment in objdef.lisp
196 (loadw res symbol symbol-hash-slot other-pointer-lowtag)
197 (inst and res (lognot #b11))))
199 ;;;; fdefinition (FDEFN) objects
201 (define-vop (fdefn-fun cell-ref) ; /pfw - alpha
202 (:variant fdefn-fun-slot other-pointer-lowtag))
204 (define-vop (safe-fdefn-fun)
205 (:args (object :scs (descriptor-reg) :to (:result 1)))
206 (:results (value :scs (descriptor-reg any-reg)))
208 (:save-p :compute-only)
210 (loadw value object fdefn-fun-slot other-pointer-lowtag)
211 (inst cmp value nil-value)
212 (let ((err-lab (generate-error-code vop undefined-fun-error object)))
213 (inst jmp :e err-lab))))
215 (define-vop (set-fdefn-fun)
217 (:translate (setf fdefn-fun))
218 (:args (function :scs (descriptor-reg) :target result)
219 (fdefn :scs (descriptor-reg)))
220 (:temporary (:sc unsigned-reg) raw)
221 (:temporary (:sc byte-reg) type)
222 (:results (result :scs (descriptor-reg)))
224 (load-type type function (- fun-pointer-lowtag))
226 (make-ea-for-object-slot function simple-fun-code-offset
228 (inst cmp type simple-fun-header-widetag)
229 (inst jmp :e normal-fn)
230 (inst lea raw (make-fixup "closure_tramp" :foreign))
232 (storew function fdefn fdefn-fun-slot other-pointer-lowtag)
233 (storew raw fdefn fdefn-raw-addr-slot other-pointer-lowtag)
234 (move result function)))
236 (define-vop (fdefn-makunbound)
238 (:translate fdefn-makunbound)
239 (:args (fdefn :scs (descriptor-reg) :target result))
240 (:results (result :scs (descriptor-reg)))
242 (storew nil-value fdefn fdefn-fun-slot other-pointer-lowtag)
243 (storew (make-fixup "undefined_tramp" :foreign)
244 fdefn fdefn-raw-addr-slot other-pointer-lowtag)
245 (move result fdefn)))
247 ;;;; binding and unbinding
249 ;;; BIND -- Establish VAL as a binding for SYMBOL. Save the old value and
250 ;;; the symbol on the binding stack and stuff the new value into the
255 (:args (val :scs (any-reg descriptor-reg))
256 (symbol :scs (descriptor-reg)))
257 (:temporary (:sc descriptor-reg :offset eax-offset) eax)
258 (:temporary (:sc unsigned-reg) tls-index temp bsp)
260 (let ((tls-index-valid (gen-label))
261 (get-tls-index-lock (gen-label))
262 (release-tls-index-lock (gen-label)))
263 (load-binding-stack-pointer bsp)
264 (loadw tls-index symbol symbol-tls-index-slot other-pointer-lowtag)
265 (inst add bsp (* binding-size n-word-bytes))
266 (store-binding-stack-pointer bsp)
267 (inst or tls-index tls-index)
268 (inst jmp :ne tls-index-valid)
271 (emit-label get-tls-index-lock)
275 (inst cmpxchg (make-ea-for-symbol-value *tls-index-lock*) temp)
276 (inst jmp :ne get-tls-index-lock)
277 ;; now with the lock held, see if the symbol's tls index has
278 ;; been set in the meantime
279 (loadw tls-index symbol symbol-tls-index-slot other-pointer-lowtag)
280 (inst or tls-index tls-index)
281 (inst jmp :ne release-tls-index-lock)
282 ;; allocate a new tls-index
283 (load-symbol-value tls-index *free-tls-index*)
284 (inst add tls-index 4) ;XXX surely we can do this more
285 (store-symbol-value tls-index *free-tls-index*) ;succintly
286 (inst sub tls-index 4)
287 (storew tls-index symbol symbol-tls-index-slot other-pointer-lowtag)
288 (emit-label release-tls-index-lock)
289 (store-symbol-value 0 *tls-index-lock*))
291 (emit-label tls-index-valid)
292 (inst fs-segment-prefix)
293 (inst mov temp (make-ea :dword :base tls-index))
294 (storew temp bsp (- binding-value-slot binding-size))
295 (storew symbol bsp (- binding-symbol-slot binding-size))
296 (inst fs-segment-prefix)
297 (inst mov (make-ea :dword :base tls-index) val))))
301 (:args (val :scs (any-reg descriptor-reg))
302 (symbol :scs (descriptor-reg)))
303 (:temporary (:sc unsigned-reg) temp bsp)
305 (load-symbol-value bsp *binding-stack-pointer*)
306 (loadw temp symbol symbol-value-slot other-pointer-lowtag)
307 (inst add bsp (* binding-size n-word-bytes))
308 (store-symbol-value bsp *binding-stack-pointer*)
309 (storew temp bsp (- binding-value-slot binding-size))
310 (storew symbol bsp (- binding-symbol-slot binding-size))
311 (storew val symbol symbol-value-slot other-pointer-lowtag)))
317 (:temporary (:sc unsigned-reg) symbol value bsp tls-index)
319 (load-binding-stack-pointer bsp)
320 (loadw symbol bsp (- binding-symbol-slot binding-size))
321 (loadw value bsp (- binding-value-slot binding-size))
323 (loadw tls-index symbol symbol-tls-index-slot other-pointer-lowtag)
324 (inst fs-segment-prefix)
325 (inst mov (make-ea :dword :base tls-index) value)
327 (storew 0 bsp (- binding-symbol-slot binding-size))
328 (storew 0 bsp (- binding-value-slot binding-size))
329 (inst sub bsp (* binding-size n-word-bytes))
330 (store-binding-stack-pointer bsp)))
334 (:temporary (:sc unsigned-reg) symbol value bsp)
336 (load-symbol-value bsp *binding-stack-pointer*)
337 (loadw symbol bsp (- binding-symbol-slot binding-size))
338 (loadw value bsp (- binding-value-slot binding-size))
339 (storew value symbol symbol-value-slot other-pointer-lowtag)
340 (storew 0 bsp (- binding-symbol-slot binding-size))
341 (storew 0 bsp (- binding-value-slot binding-size))
342 (inst sub bsp (* binding-size n-word-bytes))
343 (store-symbol-value bsp *binding-stack-pointer*)))
346 (define-vop (unbind-to-here)
347 (:args (where :scs (descriptor-reg any-reg)))
348 (:temporary (:sc unsigned-reg) symbol value bsp #!+sb-thread tls-index)
350 (load-binding-stack-pointer bsp)
355 (loadw symbol bsp (- binding-symbol-slot binding-size))
356 (inst or symbol symbol)
358 (loadw value bsp (- binding-value-slot binding-size))
359 #!-sb-thread (storew value symbol symbol-value-slot other-pointer-lowtag)
362 tls-index symbol symbol-tls-index-slot other-pointer-lowtag)
363 #!+sb-thread (inst fs-segment-prefix)
364 #!+sb-thread (inst mov (make-ea :dword :base tls-index) value)
365 (storew 0 bsp (- binding-symbol-slot binding-size))
368 (storew 0 bsp (- binding-value-slot binding-size))
369 (inst sub bsp (* binding-size n-word-bytes))
372 (store-binding-stack-pointer bsp)
378 ;;;; closure indexing
380 (define-full-reffer closure-index-ref *
381 closure-info-offset fun-pointer-lowtag
382 (any-reg descriptor-reg) * %closure-index-ref)
384 (define-full-setter set-funcallable-instance-info *
385 funcallable-instance-info-offset fun-pointer-lowtag
386 (any-reg descriptor-reg) * %set-funcallable-instance-info)
388 (define-full-reffer funcallable-instance-info *
389 funcallable-instance-info-offset fun-pointer-lowtag
390 (descriptor-reg any-reg) * %funcallable-instance-info)
392 (define-vop (closure-ref slot-ref)
393 (:variant closure-info-offset fun-pointer-lowtag))
395 (define-vop (closure-init slot-set)
396 (:variant closure-info-offset fun-pointer-lowtag))
398 ;;;; value cell hackery
400 (define-vop (value-cell-ref cell-ref)
401 (:variant value-cell-value-slot other-pointer-lowtag))
403 (define-vop (value-cell-set cell-set)
404 (:variant value-cell-value-slot other-pointer-lowtag))
406 ;;;; structure hackery
408 (define-vop (instance-length)
410 (:translate %instance-length)
411 (:args (struct :scs (descriptor-reg)))
412 (:results (res :scs (unsigned-reg)))
413 (:result-types positive-fixnum)
415 (loadw res struct 0 instance-pointer-lowtag)
416 (inst shr res n-widetag-bits)))
418 (define-full-reffer instance-index-ref * instance-slots-offset
419 instance-pointer-lowtag (any-reg descriptor-reg) * %instance-ref)
421 (define-full-setter instance-index-set * instance-slots-offset
422 instance-pointer-lowtag (any-reg descriptor-reg) * %instance-set)
425 (defknown %instance-set-conditional (instance index t t) t
428 (define-vop (instance-set-conditional)
429 (:translate %instance-set-conditional)
430 (:args (object :scs (descriptor-reg) :to :eval)
431 (slot :scs (any-reg) :to :result)
432 (old-value :scs (descriptor-reg any-reg) :target eax)
433 (new-value :scs (descriptor-reg any-reg)))
434 (:arg-types instance positive-fixnum * *)
435 (:temporary (:sc descriptor-reg :offset eax-offset
436 :from (:argument 2) :to :result :target result) eax)
437 (:results (result :scs (descriptor-reg any-reg)))
438 ;(:guard (backend-featurep :i486))
443 (inst cmpxchg (make-ea :dword :base object :index slot :scale 1
444 :disp (- (* instance-slots-offset n-word-bytes)
445 instance-pointer-lowtag))
451 ;;;; code object frobbing
453 (define-full-reffer code-header-ref * 0 other-pointer-lowtag
454 (any-reg descriptor-reg) * code-header-ref)
456 (define-full-setter code-header-set * 0 other-pointer-lowtag
457 (any-reg descriptor-reg) * code-header-set)
461 ;;;; raw instance slot accessors
463 (defun make-ea-for-raw-slot (object index instance-length n-words)
465 (any-reg (make-ea :dword
467 :index instance-length
468 :disp (- (* (- instance-slots-offset n-words)
470 instance-pointer-lowtag)))
471 (immediate (make-ea :dword :base object
472 :index instance-length
474 :disp (- (* (- instance-slots-offset n-words)
476 instance-pointer-lowtag
477 (fixnumize (tn-value index)))))))
479 (define-vop (raw-instance-ref/word)
480 (:translate %raw-instance-ref/word)
482 (:args (object :scs (descriptor-reg)) (index :scs (any-reg immediate)))
483 (:arg-types * tagged-num)
484 (:temporary (:sc unsigned-reg) tmp)
485 (:results (value :scs (unsigned-reg)))
486 (:result-types unsigned-num)
488 (loadw tmp object 0 instance-pointer-lowtag)
489 (inst shr tmp n-widetag-bits)
490 (when (sc-is index any-reg)
492 (inst sub tmp index))
493 (inst mov value (make-ea-for-raw-slot object index tmp 1))))
495 (define-vop (raw-instance-set/word)
496 (:translate %raw-instance-set/word)
498 (:args (object :scs (descriptor-reg))
499 (index :scs (any-reg immediate))
500 (value :scs (unsigned-reg) :target result))
501 (:arg-types * tagged-num unsigned-num)
502 (:temporary (:sc unsigned-reg) tmp)
503 (:results (result :scs (unsigned-reg)))
504 (:result-types unsigned-num)
506 (loadw tmp object 0 instance-pointer-lowtag)
507 (inst shr tmp n-widetag-bits)
508 (when (sc-is index any-reg)
510 (inst sub tmp index))
511 (inst mov (make-ea-for-raw-slot object index tmp 1) value)
512 (move result value)))
514 (define-vop (raw-instance-ref/single)
515 (:translate %raw-instance-ref/single)
517 (:args (object :scs (descriptor-reg)) (index :scs (any-reg immediate)))
518 (:arg-types * tagged-num)
519 (:temporary (:sc unsigned-reg) tmp)
520 (:results (value :scs (single-reg)))
521 (:result-types single-float)
523 (loadw tmp object 0 instance-pointer-lowtag)
524 (inst shr tmp n-widetag-bits)
525 (when (sc-is index any-reg)
527 (inst sub tmp index))
528 (with-empty-tn@fp-top(value)
529 (inst fld (make-ea-for-raw-slot object index tmp 1)))))
531 (define-vop (raw-instance-set/single)
532 (:translate %raw-instance-set/single)
534 (:args (object :scs (descriptor-reg))
535 (index :scs (any-reg immediate))
536 (value :scs (single-reg) :target result))
537 (:arg-types * tagged-num single-float)
538 (:temporary (:sc unsigned-reg) tmp)
539 (:results (result :scs (single-reg)))
540 (:result-types single-float)
542 (loadw tmp object 0 instance-pointer-lowtag)
543 (inst shr tmp n-widetag-bits)
544 (when (sc-is index any-reg)
546 (inst sub tmp index))
547 (unless (zerop (tn-offset value))
549 (inst fst (make-ea-for-raw-slot object index tmp 1))
551 ((zerop (tn-offset value))
552 (unless (zerop (tn-offset result))
554 ((zerop (tn-offset result))
557 (unless (location= value result)
559 (inst fxch value)))))
561 (define-vop (raw-instance-ref/double)
562 (:translate %raw-instance-ref/double)
564 (:args (object :scs (descriptor-reg)) (index :scs (any-reg immediate)))
565 (:arg-types * tagged-num)
566 (:temporary (:sc unsigned-reg) tmp)
567 (:results (value :scs (double-reg)))
568 (:result-types double-float)
570 (loadw tmp object 0 instance-pointer-lowtag)
571 (inst shr tmp n-widetag-bits)
572 (when (sc-is index any-reg)
574 (inst sub tmp index))
575 (with-empty-tn@fp-top(value)
576 (inst fldd (make-ea-for-raw-slot object index tmp 2)))))
578 (define-vop (raw-instance-set/double)
579 (:translate %raw-instance-set/double)
581 (:args (object :scs (descriptor-reg))
582 (index :scs (any-reg immediate))
583 (value :scs (double-reg) :target result))
584 (:arg-types * tagged-num double-float)
585 (:temporary (:sc unsigned-reg) tmp)
586 (:results (result :scs (double-reg)))
587 (:result-types double-float)
589 (loadw tmp object 0 instance-pointer-lowtag)
590 (inst shr tmp n-widetag-bits)
591 (when (sc-is index any-reg)
593 (inst sub tmp index))
594 (unless (zerop (tn-offset value))
596 (inst fstd (make-ea-for-raw-slot object index tmp 2))
598 ((zerop (tn-offset value))
599 (unless (zerop (tn-offset result))
601 ((zerop (tn-offset result))
604 (unless (location= value result)
606 (inst fxch value)))))
608 (define-vop (raw-instance-ref/complex-single)
609 (:translate %raw-instance-ref/complex-single)
611 (:args (object :scs (descriptor-reg))
612 (index :scs (any-reg immediate)))
613 (:arg-types * positive-fixnum)
614 (:temporary (:sc unsigned-reg) tmp)
615 (:results (value :scs (complex-single-reg)))
616 (:result-types complex-single-float)
618 (loadw tmp object 0 instance-pointer-lowtag)
619 (inst shr tmp n-widetag-bits)
620 (when (sc-is index any-reg)
622 (inst sub tmp index))
623 (let ((real-tn (complex-single-reg-real-tn value)))
624 (with-empty-tn@fp-top (real-tn)
625 (inst fld (make-ea-for-raw-slot object index tmp 2))))
626 (let ((imag-tn (complex-single-reg-imag-tn value)))
627 (with-empty-tn@fp-top (imag-tn)
628 (inst fld (make-ea-for-raw-slot object index tmp 1))))))
630 (define-vop (raw-instance-set/complex-single)
631 (:translate %raw-instance-set/complex-single)
633 (:args (object :scs (descriptor-reg))
634 (index :scs (any-reg immediate))
635 (value :scs (complex-single-reg) :target result))
636 (:arg-types * positive-fixnum complex-single-float)
637 (:temporary (:sc unsigned-reg) tmp)
638 (:results (result :scs (complex-single-reg)))
639 (:result-types complex-single-float)
641 (loadw tmp object 0 instance-pointer-lowtag)
642 (inst shr tmp n-widetag-bits)
643 (when (sc-is index any-reg)
645 (inst sub tmp index))
646 (let ((value-real (complex-single-reg-real-tn value))
647 (result-real (complex-single-reg-real-tn result)))
648 (cond ((zerop (tn-offset value-real))
650 (inst fst (make-ea-for-raw-slot object index tmp 2))
651 (unless (zerop (tn-offset result-real))
652 ;; Value is in ST0 but not result.
653 (inst fst result-real)))
655 ;; Value is not in ST0.
656 (inst fxch value-real)
657 (inst fst (make-ea-for-raw-slot object index tmp 2))
658 (cond ((zerop (tn-offset result-real))
659 ;; The result is in ST0.
660 (inst fst value-real))
662 ;; Neither value or result are in ST0
663 (unless (location= value-real result-real)
664 (inst fst result-real))
665 (inst fxch value-real))))))
666 (let ((value-imag (complex-single-reg-imag-tn value))
667 (result-imag (complex-single-reg-imag-tn result)))
668 (inst fxch value-imag)
669 (inst fst (make-ea-for-raw-slot object index tmp 1))
670 (unless (location= value-imag result-imag)
671 (inst fst result-imag))
672 (inst fxch value-imag))))
674 (define-vop (raw-instance-ref/complex-double)
675 (:translate %raw-instance-ref/complex-double)
677 (:args (object :scs (descriptor-reg))
678 (index :scs (any-reg immediate)))
679 (:arg-types * positive-fixnum)
680 (:temporary (:sc unsigned-reg) tmp)
681 (:results (value :scs (complex-double-reg)))
682 (:result-types complex-double-float)
684 (loadw tmp object 0 instance-pointer-lowtag)
685 (inst shr tmp n-widetag-bits)
686 (when (sc-is index any-reg)
688 (inst sub tmp index))
689 (let ((real-tn (complex-double-reg-real-tn value)))
690 (with-empty-tn@fp-top (real-tn)
691 (inst fldd (make-ea-for-raw-slot object index tmp 4))))
692 (let ((imag-tn (complex-double-reg-imag-tn value)))
693 (with-empty-tn@fp-top (imag-tn)
694 (inst fldd (make-ea-for-raw-slot object index tmp 2))))))
696 (define-vop (raw-instance-set/complex-double)
697 (:translate %raw-instance-set/complex-double)
699 (:args (object :scs (descriptor-reg))
700 (index :scs (any-reg immediate))
701 (value :scs (complex-double-reg) :target result))
702 (:arg-types * positive-fixnum complex-double-float)
703 (:temporary (:sc unsigned-reg) tmp)
704 (:results (result :scs (complex-double-reg)))
705 (:result-types complex-double-float)
707 (loadw tmp object 0 instance-pointer-lowtag)
708 (inst shr tmp n-widetag-bits)
709 (when (sc-is index any-reg)
711 (inst sub tmp index))
712 (let ((value-real (complex-double-reg-real-tn value))
713 (result-real (complex-double-reg-real-tn result)))
714 (cond ((zerop (tn-offset value-real))
716 (inst fstd (make-ea-for-raw-slot object index tmp 4))
717 (unless (zerop (tn-offset result-real))
718 ;; Value is in ST0 but not result.
719 (inst fstd result-real)))
721 ;; Value is not in ST0.
722 (inst fxch value-real)
723 (inst fstd (make-ea-for-raw-slot object index tmp 4))
724 (cond ((zerop (tn-offset result-real))
725 ;; The result is in ST0.
726 (inst fstd value-real))
728 ;; Neither value or result are in ST0
729 (unless (location= value-real result-real)
730 (inst fstd result-real))
731 (inst fxch value-real))))))
732 (let ((value-imag (complex-double-reg-imag-tn value))
733 (result-imag (complex-double-reg-imag-tn result)))
734 (inst fxch value-imag)
735 (inst fstd (make-ea-for-raw-slot object index tmp 2))
736 (unless (location= value-imag result-imag)
737 (inst fstd result-imag))
738 (inst fxch value-imag))))