1 ;;;; the x86 VM definition of operand loading/saving and the MOVE vop
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 (define-move-fun (load-immediate 1) (vop x y)
16 (any-reg descriptor-reg))
17 (let ((val (tn-value x)))
22 (inst mov y (fixnumize val))))
26 (inst mov y (logior (ash (char-code val) n-widetag-bits)
27 character-widetag))))))
29 (define-move-fun (load-number 1) (vop x y)
30 ((immediate) (signed-reg unsigned-reg))
31 (let ((val (tn-value x)))
36 (define-move-fun (load-character 1) (vop x y)
37 ((immediate) (character-reg))
38 (inst mov y (char-code (tn-value x))))
40 (define-move-fun (load-system-area-pointer 1) (vop x y)
41 ((immediate) (sap-reg))
42 (inst mov y (sap-int (tn-value x))))
44 (define-move-fun (load-constant 5) (vop x y)
45 ((constant) (descriptor-reg any-reg))
48 (define-move-fun (load-stack 5) (vop x y)
49 ((control-stack) (any-reg descriptor-reg)
50 (character-stack) (character-reg)
52 (signed-stack) (signed-reg)
53 (unsigned-stack) (unsigned-reg))
56 (define-move-fun (store-stack 5) (vop x y)
57 ((any-reg descriptor-reg) (control-stack)
58 (character-reg) (character-stack)
60 (signed-reg) (signed-stack)
61 (unsigned-reg) (unsigned-stack))
66 (:args (x :scs (any-reg descriptor-reg immediate) :target y
67 :load-if (not (location= x y))))
68 (:results (y :scs (any-reg descriptor-reg)
70 (not (or (location= x y)
71 (and (sc-is x any-reg descriptor-reg immediate)
72 (sc-is y control-stack))))))
76 (if (and (sc-is x immediate)
77 (sc-is y any-reg descriptor-reg control-stack))
78 (let ((val (tn-value x)))
81 (if (and (zerop val) (sc-is y any-reg descriptor-reg))
83 (inst mov y (fixnumize val))))
85 (inst mov y (+ nil-value (static-symbol-offset val))))
87 (inst mov y (logior (ash (char-code val) n-widetag-bits)
88 character-widetag)))))
91 (define-move-vop move :move
92 (any-reg descriptor-reg immediate)
93 (any-reg descriptor-reg))
95 ;;; Make MOVE the check VOP for T so that type check generation
96 ;;; doesn't think it is a hairy type. This also allows checking of a
97 ;;; few of the values in a continuation to fall out.
98 (primitive-type-vop move (:check) t)
100 ;;; The MOVE-ARG VOP is used for moving descriptor values into
101 ;;; another frame for argument or known value passing.
103 ;;; Note: It is not going to be possible to move a constant directly
104 ;;; to another frame, except if the destination is a register and in
105 ;;; this case the loading works out.
106 (define-vop (move-arg)
107 (:args (x :scs (any-reg descriptor-reg immediate) :target y
108 :load-if (not (and (sc-is y any-reg descriptor-reg)
109 (sc-is x control-stack))))
111 :load-if (not (sc-is y any-reg descriptor-reg))))
115 ((any-reg descriptor-reg)
116 (if (sc-is x immediate)
117 (let ((val (tn-value x)))
122 (inst mov y (fixnumize val))))
126 (inst mov y (logior (ash (char-code val) n-widetag-bits)
127 character-widetag)))))
130 (let ((frame-offset (if (= (tn-offset fp) esp-offset)
134 (frame-word-offset (tn-offset y)))))
135 (if (sc-is x immediate)
136 (let ((val (tn-value x)))
139 (storew (fixnumize val) fp frame-offset))
141 (storew (+ nil-value (static-symbol-offset val))
144 (storew (logior (ash (char-code val) n-widetag-bits)
147 (storew x fp frame-offset)))))))
149 (define-move-vop move-arg :move-arg
150 (any-reg descriptor-reg)
151 (any-reg descriptor-reg))
155 ;;; This VOP exists just to begin the lifetime of a TN that couldn't
156 ;;; be written legally due to a type error. An error is signalled
157 ;;; before this VOP is so we don't need to do anything (not that there
158 ;;; would be anything sensible to do anyway.)
159 (define-vop (illegal-move)
164 (:save-p :compute-only)
166 (error-call vop object-not-type-error x type)))
168 ;;;; moves and coercions
170 ;;; These MOVE-TO-WORD VOPs move a tagged integer to a raw full-word
171 ;;; representation. Similarly, the MOVE-FROM-WORD VOPs converts a raw
172 ;;; integer to a tagged bignum or fixnum.
174 ;;; Arg is a fixnum, so just shift it. We need a type restriction
175 ;;; because some possible arg SCs (control-stack) overlap with
176 ;;; possible bignum arg SCs.
177 (define-vop (move-to-word/fixnum)
178 (:args (x :scs (any-reg descriptor-reg) :target y
179 :load-if (not (location= x y))))
180 (:results (y :scs (signed-reg unsigned-reg)
181 :load-if (not (location= x y))))
182 (:arg-types tagged-num)
183 (:note "fixnum untagging")
187 (define-move-vop move-to-word/fixnum :move
188 (any-reg descriptor-reg) (signed-reg unsigned-reg))
190 ;;; Arg is a non-immediate constant, load it.
191 (define-vop (move-to-word-c)
192 (:args (x :scs (constant)))
193 (:results (y :scs (signed-reg unsigned-reg)))
194 (:note "constant load")
196 (inst mov y (tn-value x))))
197 (define-move-vop move-to-word-c :move
198 (constant) (signed-reg unsigned-reg))
201 ;;; Arg is a fixnum or bignum, figure out which and load if necessary.
202 (define-vop (move-to-word/integer)
203 (:args (x :scs (descriptor-reg) :target eax))
204 (:results (y :scs (signed-reg unsigned-reg)))
205 (:note "integer to untagged word coercion")
206 (:temporary (:sc unsigned-reg :offset eax-offset
207 :from (:argument 0) :to (:result 0) :target y) eax)
212 (loadw y eax bignum-digits-offset other-pointer-lowtag)
218 (define-move-vop move-to-word/integer :move
219 (descriptor-reg) (signed-reg unsigned-reg))
222 ;;; Result is a fixnum, so we can just shift. We need the result type
223 ;;; restriction because of the control-stack ambiguity noted above.
224 (define-vop (move-from-word/fixnum)
225 (:args (x :scs (signed-reg unsigned-reg) :target y
226 :load-if (not (location= x y))))
227 (:results (y :scs (any-reg descriptor-reg)
228 :load-if (not (location= x y))))
229 (:result-types tagged-num)
230 (:note "fixnum tagging")
232 (cond ((and (sc-is x signed-reg unsigned-reg)
233 (not (location= x y)))
234 ;; Uses 7 bytes, but faster on the Pentium
235 (inst lea y (make-ea :dword :index x :scale 4)))
237 ;; Uses: If x is a reg 2 + 3; if x = y uses only 3 bytes
240 (define-move-vop move-from-word/fixnum :move
241 (signed-reg unsigned-reg) (any-reg descriptor-reg))
243 ;;; Result may be a bignum, so we have to check. Use a worst-case cost
244 ;;; to make sure people know they may be number consing.
246 ;;; KLUDGE: I assume this is suppressed in favor of the "faster inline
247 ;;; version" below. (See also mysterious comment "we don't want a VOP
248 ;;; on this one" on DEFINE-ASSEMBLY-ROUTINE (MOVE-FROM-SIGNED) in
249 ;;; "src/assembly/x86/alloc.lisp".) -- WHN 19990916
251 (define-vop (move-from-signed)
252 (:args (x :scs (signed-reg unsigned-reg) :target eax))
253 (:temporary (:sc unsigned-reg :offset eax-offset :from (:argument 0)) eax)
254 (:temporary (:sc unsigned-reg :offset ebx-offset :to (:result 0) :target y)
256 (:temporary (:sc unsigned-reg :offset ecx-offset
257 :from (:argument 0) :to (:result 0)) ecx)
259 (:results (y :scs (any-reg descriptor-reg)))
260 (:note "signed word to integer coercion")
263 (inst call (make-fixup 'move-from-signed :assembly-routine))
265 ;;; Faster inline version,
266 ;;; KLUDGE: Do we really want the faster inline version? It's sorta big.
267 ;;; It is nice that it doesn't use any temporaries, though. -- WHN 19990916
268 (define-vop (move-from-signed)
269 (:args (x :scs (signed-reg unsigned-reg) :to :result))
270 (:results (y :scs (any-reg descriptor-reg) :from :argument))
271 (:note "signed word to integer coercion")
274 (aver (not (location= x y)))
275 (let ((bignum (gen-label))
283 ;; KLUDGE: The sequence above leaves a DESCRIPTOR-REG Y in a
284 ;; non-descriptor state for a while. Does that matter? Does it
285 ;; matter in GENGC but not in GENCGC? Is this written down
289 ;; Also, the sequence above seems rather twisty. Why not something
290 ;; more obvious along the lines of
292 ;; inst tst x #xc0000000
293 ;; inst jmp :nz bignum
297 (assemble (*elsewhere*)
299 (with-fixed-allocation
300 (y bignum-widetag (+ bignum-digits-offset 1) node)
301 (storew x y bignum-digits-offset other-pointer-lowtag))
303 (define-move-vop move-from-signed :move
304 (signed-reg) (descriptor-reg))
306 ;;; Check for fixnum, and possibly allocate one or two word bignum
307 ;;; result. Use a worst-case cost to make sure people know they may be
310 (define-vop (move-from-unsigned)
311 (:args (x :scs (signed-reg unsigned-reg) :target eax))
312 (:temporary (:sc unsigned-reg :offset eax-offset :from (:argument 0)) eax)
313 (:temporary (:sc unsigned-reg :offset ebx-offset :to (:result 0) :target y)
315 (:temporary (:sc unsigned-reg :offset ecx-offset
316 :from (:argument 0) :to (:result 0)) ecx)
318 (:results (y :scs (any-reg descriptor-reg)))
319 (:note "unsigned word to integer coercion")
322 (inst call (make-fixup 'move-from-unsigned :assembly-routine))
324 ;;; Faster inline version.
325 ;;; KLUDGE: Do we really want the faster inline version? It seems awfully big..
326 ;;; If we really want speed, most likely it's only important in the non-consing
327 ;;; case, so how about about making the *ELSEWHERE* stuff into a subroutine? --
329 (define-vop (move-from-unsigned)
330 (:args (x :scs (signed-reg unsigned-reg) :to :save))
331 (:temporary (:sc unsigned-reg) alloc)
332 (:results (y :scs (any-reg descriptor-reg)))
334 (:note "unsigned word to integer coercion")
336 (aver (not (location= x y)))
337 (aver (not (location= x alloc)))
338 (aver (not (location= y alloc)))
339 (let ((bignum (gen-label))
341 (one-word-bignum (gen-label))
343 (inst test x #xe0000000)
344 (inst jmp :nz bignum)
346 (inst lea y (make-ea :dword :index x :scale 4)) ; Faster but bigger.
351 (assemble (*elsewhere*)
353 ;; Note: As on the mips port, space for a two word bignum is
354 ;; always allocated and the header size is set to either one
355 ;; or two words as appropriate.
356 (inst jmp :ns one-word-bignum)
358 (inst mov y (logior (ash (1- (+ bignum-digits-offset 2))
362 (emit-label one-word-bignum)
363 (inst mov y (logior (ash (1- (+ bignum-digits-offset 1))
368 (allocation alloc (pad-data-block (+ bignum-digits-offset 2)) node)
370 (inst lea y (make-ea :byte :base alloc :disp other-pointer-lowtag))
371 (storew x y bignum-digits-offset other-pointer-lowtag))
373 (define-move-vop move-from-unsigned :move
374 (unsigned-reg) (descriptor-reg))
376 ;;; Move untagged numbers.
377 (define-vop (word-move)
378 (:args (x :scs (signed-reg unsigned-reg) :target y
379 :load-if (not (location= x y))))
380 (:results (y :scs (signed-reg unsigned-reg)
382 (not (or (location= x y)
383 (and (sc-is x signed-reg unsigned-reg)
384 (sc-is y signed-stack unsigned-stack))))))
387 (:note "word integer move")
390 (define-move-vop word-move :move
391 (signed-reg unsigned-reg) (signed-reg unsigned-reg))
393 ;;; Move untagged number arguments/return-values.
394 (define-vop (move-word-arg)
395 (:args (x :scs (signed-reg unsigned-reg) :target y)
396 (fp :scs (any-reg) :load-if (not (sc-is y sap-reg))))
398 (:note "word integer argument move")
401 ((signed-reg unsigned-reg)
403 ((signed-stack unsigned-stack)
404 (if (= (tn-offset fp) esp-offset)
405 (storew x fp (tn-offset y)) ; c-call
406 (storew x fp (frame-word-offset (tn-offset y))))))))
407 (define-move-vop move-word-arg :move-arg
408 (descriptor-reg any-reg signed-reg unsigned-reg) (signed-reg unsigned-reg))
410 ;;; Use standard MOVE-ARG and coercion to move an untagged number
411 ;;; to a descriptor passing location.
412 (define-move-vop move-arg :move-arg
413 (signed-reg unsigned-reg) (any-reg descriptor-reg))