1 ;;;; function call 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 ;;;; interfaces to IR2 conversion
16 ;;; Return a wired TN describing the N'th full call argument passing
18 (!def-vm-support-routine standard-arg-location (n)
19 (declare (type unsigned-byte n))
20 (if (< n register-arg-count)
21 (make-wired-tn *backend-t-primitive-type* descriptor-reg-sc-number
22 (nth n *register-arg-offsets*))
23 (make-wired-tn *backend-t-primitive-type* control-stack-sc-number n)))
25 ;;; Make a passing location TN for a local call return PC.
27 ;;; Always wire the return PC location to the stack in its standard
29 (!def-vm-support-routine make-return-pc-passing-location (standard)
30 (declare (ignore standard))
31 (make-wired-tn (primitive-type-or-lose 'system-area-pointer)
32 sap-stack-sc-number return-pc-save-offset))
34 ;;; This is similar to MAKE-RETURN-PC-PASSING-LOCATION, but makes a
35 ;;; location to pass OLD-FP in.
37 ;;; This is wired in both the standard and the local-call conventions,
38 ;;; because we want to be able to assume it's always there. Besides,
39 ;;; the x86 doesn't have enough registers to really make it profitable
40 ;;; to pass it in a register.
41 (!def-vm-support-routine make-old-fp-passing-location (standard)
42 (declare (ignore standard))
43 (make-wired-tn *fixnum-primitive-type* control-stack-sc-number
46 ;;; Make the TNs used to hold OLD-FP and RETURN-PC within the current
47 ;;; function. We treat these specially so that the debugger can find
48 ;;; them at a known location.
50 ;;; Without using a save-tn - which does not make much sense if it is
51 ;;; wired to the stack?
52 (!def-vm-support-routine make-old-fp-save-location (physenv)
53 (physenv-debug-live-tn (make-wired-tn *fixnum-primitive-type*
54 control-stack-sc-number
57 (!def-vm-support-routine make-return-pc-save-location (physenv)
58 (physenv-debug-live-tn
59 (make-wired-tn (primitive-type-or-lose 'system-area-pointer)
60 sap-stack-sc-number return-pc-save-offset)
63 ;;; Make a TN for the standard argument count passing location. We only
64 ;;; need to make the standard location, since a count is never passed when we
65 ;;; are using non-standard conventions.
66 (!def-vm-support-routine make-arg-count-location ()
67 (make-wired-tn *fixnum-primitive-type* any-reg-sc-number ecx-offset))
69 ;;; Make a TN to hold the number-stack frame pointer. This is allocated
70 ;;; once per component, and is component-live.
71 (!def-vm-support-routine make-nfp-tn ()
72 (make-restricted-tn *fixnum-primitive-type* ignore-me-sc-number))
74 (!def-vm-support-routine make-stack-pointer-tn ()
75 (make-normal-tn *fixnum-primitive-type*))
77 (!def-vm-support-routine make-number-stack-pointer-tn ()
78 (make-restricted-tn *fixnum-primitive-type* ignore-me-sc-number))
80 ;;; Return a list of TNs that can be used to represent an unknown-values
81 ;;; continuation within a function.
82 (!def-vm-support-routine make-unknown-values-locations ()
83 (list (make-stack-pointer-tn)
84 (make-normal-tn *fixnum-primitive-type*)))
86 ;;; This function is called by the ENTRY-ANALYZE phase, allowing
87 ;;; VM-dependent initialization of the IR2-COMPONENT structure. We
88 ;;; push placeholder entries in the CONSTANTS to leave room for
89 ;;; additional noise in the code object header.
90 (!def-vm-support-routine select-component-format (component)
91 (declare (type component component))
92 ;; The 1+ here is because for the x86 the first constant is a
93 ;; pointer to a list of fixups, or NIL if the code object has none.
94 ;; (If I understand correctly, the fixups are needed at GC copy
95 ;; time because the X86 code isn't relocatable.)
97 ;; KLUDGE: It'd be cleaner to have the fixups entry be a named
98 ;; element of the CODE (aka component) primitive object. However,
99 ;; it's currently a large, tricky, error-prone chore to change
100 ;; the layout of any primitive object, so for the foreseeable future
101 ;; we'll just live with this ugliness. -- WHN 2002-01-02
102 (dotimes (i (1+ code-constants-offset))
103 (vector-push-extend nil
104 (ir2-component-constants (component-info component))))
109 ;;; This is used for setting up the Old-FP in local call.
110 (define-vop (current-fp)
111 (:results (val :scs (any-reg control-stack)))
115 ;;; We don't have a separate NFP, so we don't need to do anything here.
116 (define-vop (compute-old-nfp)
122 (define-vop (xep-allocate-frame)
123 (:info start-lab copy-more-arg-follows)
126 (align n-lowtag-bits)
127 (trace-table-entry trace-table-fun-prologue)
128 (emit-label start-lab)
129 ;; Skip space for the function header.
130 (inst simple-fun-header-word)
131 (dotimes (i (1- simple-fun-code-offset))
134 ;; The start of the actual code.
135 ;; Save the return-pc.
136 (popw ebp-tn (- (1+ return-pc-save-offset)))
138 ;; If copy-more-arg follows it will allocate the correct stack
139 ;; size. The stack is not allocated first here as this may expose
140 ;; args on the stack if they take up more space than the frame!
141 (unless copy-more-arg-follows
142 ;; The args fit within the frame so just allocate the frame.
144 (make-ea :dword :base ebp-tn
145 :disp (- (* n-word-bytes
146 (max 3 (sb-allocated-size 'stack)))))))
148 (trace-table-entry trace-table-normal)))
150 ;;; This is emitted directly before either a known-call-local, call-local,
151 ;;; or a multiple-call-local. All it does is allocate stack space for the
152 ;;; callee (who has the same size stack as us).
153 (define-vop (allocate-frame)
154 (:results (res :scs (any-reg control-stack))
160 (inst sub esp-tn (* n-word-bytes (sb-allocated-size 'stack)))))
162 ;;; Allocate a partial frame for passing stack arguments in a full
163 ;;; call. NARGS is the number of arguments passed. We allocate at
164 ;;; least 3 slots, because the XEP noise is going to want to use them
165 ;;; before it can extend the stack.
166 (define-vop (allocate-full-call-frame)
168 (:results (res :scs (any-reg control-stack)))
171 (inst sub esp-tn (* (max nargs 3) n-word-bytes))))
173 ;;; Emit code needed at the return-point from an unknown-values call
174 ;;; for a fixed number of values. Values is the head of the TN-REF
175 ;;; list for the locations that the values are to be received into.
176 ;;; Nvals is the number of values that are to be received (should
177 ;;; equal the length of Values).
179 ;;; MOVE-TEMP is a DESCRIPTOR-REG TN used as a temporary.
181 ;;; This code exploits the fact that in the unknown-values convention,
182 ;;; a single value return returns at the return PC + 2, whereas a
183 ;;; return of other than one value returns directly at the return PC.
185 ;;; If 0 or 1 values are expected, then we just emit an instruction to
186 ;;; reset the SP (which will only be executed when other than 1 value
189 ;;; In the general case we have to do three things:
190 ;;; -- Default unsupplied register values. This need only be done
191 ;;; when a single value is returned, since register values are
192 ;;; defaulted by the called in the non-single case.
193 ;;; -- Default unsupplied stack values. This needs to be done whenever
194 ;;; there are stack values.
195 ;;; -- Reset SP. This must be done whenever other than 1 value is
196 ;;; returned, regardless of the number of values desired.
197 (defun default-unknown-values (vop values nvals)
198 (declare (type (or tn-ref null) values)
199 (type unsigned-byte nvals))
202 (note-this-location vop :single-value-return)
203 (inst mov esp-tn ebx-tn))
204 ((<= nvals register-arg-count)
205 (let ((regs-defaulted (gen-label)))
206 (note-this-location vop :unknown-return)
207 (inst jmp-short regs-defaulted)
208 ;; Default the unsuppled registers.
209 (let* ((2nd-tn-ref (tn-ref-across values))
210 (2nd-tn (tn-ref-tn 2nd-tn-ref)))
211 (inst mov 2nd-tn nil-value)
214 for tn-ref = (tn-ref-across 2nd-tn-ref)
215 then (tn-ref-across tn-ref)
216 for count from 2 below register-arg-count
217 do (inst mov (tn-ref-tn tn-ref) 2nd-tn))))
218 (inst mov ebx-tn esp-tn)
219 (emit-label regs-defaulted)
220 (inst mov esp-tn ebx-tn)))
222 ;; The number of bytes depends on the relative jump instructions.
223 ;; Best case is 31+(n-3)*14, worst case is 35+(n-3)*18. For
224 ;; NVALS=6 that is 73/89 bytes, and for NVALS=7 that is 87/107
225 ;; bytes which is likely better than using the blt below.
226 (let ((regs-defaulted (gen-label))
227 (defaulting-done (gen-label))
228 (default-stack-slots (gen-label)))
229 (note-this-location vop :unknown-return)
230 ;; Branch off to the MV case.
231 (inst jmp-short regs-defaulted)
232 ;; Do the single value case.
233 ;; Default the register args
234 (inst mov eax-tn nil-value)
236 (val (tn-ref-across values) (tn-ref-across val)))
237 ((= i (min nvals register-arg-count)))
238 (inst mov (tn-ref-tn val) eax-tn))
240 ;; Fake other registers so it looks like we returned with all the
241 ;; registers filled in.
244 (inst jmp default-stack-slots)
246 (emit-label regs-defaulted)
248 (inst mov eax-tn nil-value)
249 (storew edx-tn ebx-tn -1)
250 (collect ((defaults))
251 (do ((i register-arg-count (1+ i))
252 (val (do ((i 0 (1+ i))
253 (val values (tn-ref-across val)))
254 ((= i register-arg-count) val))
255 (tn-ref-across val)))
257 (let ((default-lab (gen-label))
258 (tn (tn-ref-tn val)))
259 (defaults (cons default-lab tn))
261 (inst cmp ecx-tn (fixnumize i))
262 (inst jmp :be default-lab)
263 (loadw edx-tn ebx-tn (- (1+ i)))
264 (inst mov tn edx-tn)))
266 (emit-label defaulting-done)
267 (loadw edx-tn ebx-tn -1)
270 (let ((defaults (defaults)))
272 (assemble (*elsewhere*)
273 (trace-table-entry trace-table-fun-prologue)
274 (emit-label default-stack-slots)
275 (dolist (default defaults)
276 (emit-label (car default))
277 (inst mov (cdr default) eax-tn))
278 (inst jmp defaulting-done)
279 (trace-table-entry trace-table-normal)))))))
281 ;; 91 bytes for this branch.
282 (let ((regs-defaulted (gen-label))
283 (restore-edi (gen-label))
284 (no-stack-args (gen-label))
285 (default-stack-vals (gen-label))
286 (count-okay (gen-label)))
287 (note-this-location vop :unknown-return)
288 ;; Branch off to the MV case.
289 (inst jmp-short regs-defaulted)
291 ;; Default the register args, and set up the stack as if we
292 ;; entered the MV return point.
293 (inst mov ebx-tn esp-tn)
295 (inst mov edi-tn nil-value)
297 (inst mov esi-tn edi-tn)
298 ;; Compute a pointer to where to put the [defaulted] stack values.
299 (emit-label no-stack-args)
301 (make-ea :dword :base ebp-tn
302 :disp (* (- (1+ register-arg-count)) n-word-bytes)))
303 ;; Load EAX with NIL so we can quickly store it, and set up
304 ;; stuff for the loop.
305 (inst mov eax-tn nil-value)
307 (inst mov ecx-tn (- nvals register-arg-count))
308 ;; solaris requires DF being zero.
310 ;; Jump into the default loop.
311 (inst jmp default-stack-vals)
313 ;; The regs are defaulted. We need to copy any stack arguments,
314 ;; and then default the remaining stack arguments.
315 (emit-label regs-defaulted)
317 (storew edi-tn ebx-tn (- (1+ 1)))
318 ;; Compute the number of stack arguments, and if it's zero or
319 ;; less, don't copy any stack arguments.
320 (inst sub ecx-tn (fixnumize register-arg-count))
321 (inst jmp :le no-stack-args)
323 ;; Throw away any unwanted args.
324 (inst cmp ecx-tn (fixnumize (- nvals register-arg-count)))
325 (inst jmp :be count-okay)
326 (inst mov ecx-tn (fixnumize (- nvals register-arg-count)))
327 (emit-label count-okay)
328 ;; Save the number of stack values.
329 (inst mov eax-tn ecx-tn)
330 ;; Compute a pointer to where the stack args go.
332 (make-ea :dword :base ebp-tn
333 :disp (* (- (1+ register-arg-count)) n-word-bytes)))
334 ;; Save ESI, and compute a pointer to where the args come from.
335 (storew esi-tn ebx-tn (- (1+ 2)))
337 (make-ea :dword :base ebx-tn
338 :disp (* (- (1+ register-arg-count)) n-word-bytes)))
340 (inst shr ecx-tn word-shift) ; make word count
344 ;; solaris requires DF being zero.
347 (loadw esi-tn ebx-tn (- (1+ 2)))
348 ;; Now we have to default the remaining args. Find out how many.
349 (inst sub eax-tn (fixnumize (- nvals register-arg-count)))
351 ;; If none, then just blow out of here.
352 (inst jmp :le restore-edi)
353 (inst mov ecx-tn eax-tn)
354 (inst shr ecx-tn word-shift) ; word count
355 ;; Load EAX with NIL for fast storing.
356 (inst mov eax-tn nil-value)
358 (emit-label default-stack-vals)
361 ;; solaris requires DF being zero.
363 ;; Restore EDI, and reset the stack.
364 (emit-label restore-edi)
365 (loadw edi-tn ebx-tn (- (1+ 1)))
366 (inst mov esp-tn ebx-tn))))
369 ;;;; unknown values receiving
371 ;;; Emit code needed at the return point for an unknown-values call
372 ;;; for an arbitrary number of values.
374 ;;; We do the single and non-single cases with no shared code: there
375 ;;; doesn't seem to be any potential overlap, and receiving a single
376 ;;; value is more important efficiency-wise.
378 ;;; When there is a single value, we just push it on the stack,
379 ;;; returning the old SP and 1.
381 ;;; When there is a variable number of values, we move all of the
382 ;;; argument registers onto the stack, and return ARGS and NARGS.
384 ;;; ARGS and NARGS are TNs wired to the named locations. We must
385 ;;; explicitly allocate these TNs, since their lifetimes overlap with
386 ;;; the results start and count. (Also, it's nice to be able to target
388 (defun receive-unknown-values (args nargs start count)
389 (declare (type tn args nargs start count))
390 (let ((variable-values (gen-label))
392 (inst jmp-short variable-values)
394 (cond ((location= start (first *register-arg-tns*))
395 (inst push (first *register-arg-tns*))
396 (inst lea start (make-ea :dword :base esp-tn :disp 4)))
397 (t (inst mov start esp-tn)
398 (inst push (first *register-arg-tns*))))
399 (inst mov count (fixnumize 1))
402 (emit-label variable-values)
403 ;; dtc: this writes the registers onto the stack even if they are
404 ;; not needed, only the number specified in ecx are used and have
405 ;; stack allocated to them. No harm is done.
407 for arg in *register-arg-tns*
409 do (storew arg args i))
416 ;;; VOP that can be inherited by unknown values receivers. The main thing this
417 ;;; handles is allocation of the result temporaries.
418 (define-vop (unknown-values-receiver)
419 (:temporary (:sc descriptor-reg :offset ebx-offset
420 :from :eval :to (:result 0))
422 (:temporary (:sc any-reg :offset ecx-offset
423 :from :eval :to (:result 1))
425 (:results (start :scs (any-reg control-stack))
426 (count :scs (any-reg control-stack))))
428 ;;;; local call with unknown values convention return
430 ;;; Non-TR local call for a fixed number of values passed according to
431 ;;; the unknown values convention.
433 ;;; FP is the frame pointer in install before doing the call.
435 ;;; NFP would be the number-stack frame pointer if we had a separate
438 ;;; Args are the argument passing locations, which are specified only
439 ;;; to terminate their lifetimes in the caller.
441 ;;; VALUES are the return value locations (wired to the standard
442 ;;; passing locations). NVALS is the number of values received.
444 ;;; Save is the save info, which we can ignore since saving has been
447 ;;; TARGET is a continuation pointing to the start of the called
449 (define-vop (call-local)
453 (:results (values :more t))
455 (:move-args :local-call)
456 (:info arg-locs callee target nvals)
458 (:ignore nfp arg-locs args #+nil callee)
460 (trace-table-entry trace-table-call-site)
463 (let ((ret-tn (callee-return-pc-tn callee)))
465 (format t "*call-local ~S; tn-kind ~S; tn-save-tn ~S; its tn-kind ~S~%"
466 ret-tn (sb!c::tn-kind ret-tn) (sb!c::tn-save-tn ret-tn)
467 (sb!c::tn-kind (sb!c::tn-save-tn ret-tn)))
469 ;; Is the return-pc on the stack or in a register?
472 #+nil (format t "*call-local: ret-tn on stack; offset=~S~%"
474 (storew (make-fixup nil :code-object return)
475 ebp-tn (- (1+ (tn-offset ret-tn)))))
477 (inst lea ret-tn (make-fixup nil :code-object return)))))
479 (note-this-location vop :call-site)
482 (default-unknown-values vop values nvals)
483 (trace-table-entry trace-table-normal)))
485 ;;; Non-TR local call for a variable number of return values passed according
486 ;;; to the unknown values convention. The results are the start of the values
487 ;;; glob and the number of values received.
488 (define-vop (multiple-call-local unknown-values-receiver)
493 (:move-args :local-call)
494 (:info save callee target)
495 (:ignore args save nfp #+nil callee)
498 (trace-table-entry trace-table-call-site)
501 (let ((ret-tn (callee-return-pc-tn callee)))
503 (format t "*multiple-call-local ~S; tn-kind ~S; tn-save-tn ~S; its tn-kind ~S~%"
504 ret-tn (sb!c::tn-kind ret-tn) (sb!c::tn-save-tn ret-tn)
505 (sb!c::tn-kind (sb!c::tn-save-tn ret-tn)))
507 ;; Is the return-pc on the stack or in a register?
510 #+nil (format t "*multiple-call-local: ret-tn on stack; offset=~S~%"
513 (storew (make-fixup nil :code-object return)
514 ebp-tn (- (1+ (tn-offset ret-tn)))))
517 (inst lea ret-tn (make-fixup nil :code-object return)))))
519 (note-this-location vop :call-site)
522 (note-this-location vop :unknown-return)
523 (receive-unknown-values values-start nvals start count)
524 (trace-table-entry trace-table-normal)))
526 ;;;; local call with known values return
528 ;;; Non-TR local call with known return locations. Known-value return
529 ;;; works just like argument passing in local call.
531 ;;; Note: we can't use normal load-tn allocation for the fixed args,
532 ;;; since all registers may be tied up by the more operand. Instead,
533 ;;; we use MAYBE-LOAD-STACK-TN.
534 (define-vop (known-call-local)
538 (:results (res :more t))
539 (:move-args :local-call)
541 (:info save callee target)
542 (:ignore args res save nfp #+nil callee)
545 (trace-table-entry trace-table-call-site)
548 (let ((ret-tn (callee-return-pc-tn callee)))
551 (format t "*known-call-local ~S; tn-kind ~S; tn-save-tn ~S; its tn-kind ~S~%"
552 ret-tn (sb!c::tn-kind ret-tn) (sb!c::tn-save-tn ret-tn)
553 (sb!c::tn-kind (sb!c::tn-save-tn ret-tn)))
555 ;; Is the return-pc on the stack or in a register?
558 #+nil (format t "*known-call-local: ret-tn on stack; offset=~S~%"
561 (storew (make-fixup nil :code-object return)
562 ebp-tn (- (1+ (tn-offset ret-tn)))))
565 (inst lea ret-tn (make-fixup nil :code-object return)))))
567 (note-this-location vop :call-site)
570 (note-this-location vop :known-return)
571 (trace-table-entry trace-table-normal)))
573 ;;; Return from known values call. We receive the return locations as
574 ;;; arguments to terminate their lifetimes in the returning function. We
575 ;;; restore FP and CSP and jump to the Return-PC.
577 ;;; We can assume we know exactly where old-fp and return-pc are because
578 ;;; make-old-fp-save-location and make-return-pc-save-location always
579 ;;; return the same place.
581 (define-vop (known-return)
583 (return-pc :scs (any-reg immediate-stack) :target rpc)
585 (:move-args :known-return)
587 (:temporary (:sc unsigned-reg :from (:argument 1)) rpc)
588 (:ignore val-locs vals)
591 (trace-table-entry trace-table-fun-epilogue)
592 ;; Save the return-pc in a register 'cause the frame-pointer is
593 ;; going away. Note this not in the usual stack location so we
596 ;; Restore the stack.
598 ;; Restore the old fp. We know OLD-FP is going to be in its stack
599 ;; save slot, which is a different frame that than this one,
600 ;; so we don't have to worry about having just cleared
601 ;; most of the stack.
604 (trace-table-entry trace-table-normal)))
606 ;;; From Douglas Crosher
607 ;;; Return from known values call. We receive the return locations as
608 ;;; arguments to terminate their lifetimes in the returning function. We
609 ;;; restore FP and CSP and jump to the Return-PC.
611 ;;; The old-fp may be either in a register or on the stack in its
612 ;;; standard save locations - slot 0.
614 ;;; The return-pc may be in a register or on the stack in any slot.
615 (define-vop (known-return)
619 (:move-args :known-return)
621 (:ignore val-locs vals)
624 (trace-table-entry trace-table-fun-epilogue)
626 #+nil (format t "*known-return: old-fp ~S, tn-kind ~S; ~S ~S~%"
627 old-fp (sb!c::tn-kind old-fp) (sb!c::tn-save-tn old-fp)
628 (sb!c::tn-kind (sb!c::tn-save-tn old-fp)))
630 #+nil (format t "*known-return: return-pc ~S, tn-kind ~S; ~S ~S~%"
631 return-pc (sb!c::tn-kind return-pc)
632 (sb!c::tn-save-tn return-pc)
633 (sb!c::tn-kind (sb!c::tn-save-tn return-pc)))
635 ;; return-pc may be either in a register or on the stack.
641 #+nil (format t "*known-return: old-fp ~S on stack; offset=~S~%"
642 old-fp (tn-offset old-fp))
644 (cond ((zerop (tn-offset old-fp))
645 ;; Zot all of the stack except for the old-fp.
646 (inst lea esp-tn (make-ea :dword :base ebp-tn
647 :disp (- (* (1+ ocfp-save-offset)
649 ;; Restore the old fp from its save location on the stack,
650 ;; and zot the stack.
654 (cerror "Continue anyway"
655 "VOP return-local doesn't work if old-fp (in slot ~
656 ~S) is not in slot 0"
657 (tn-offset old-fp)))))
659 ((any-reg descriptor-reg)
660 ;; Zot all the stack.
662 ;; Restore the old-fp.
663 (move ebp-tn old-fp)))
665 ;; Return; return-pc is in a register.
666 (inst jmp return-pc))
670 #+nil (format t "*known-return: return-pc ~S on stack; offset=~S~%"
671 return-pc (tn-offset return-pc))
673 ;; Zot all of the stack except for the old-fp and return-pc.
675 (make-ea :dword :base ebp-tn
676 :disp (- (* (1+ (tn-offset return-pc)) n-word-bytes))))
677 ;; Restore the old fp. old-fp may be either on the stack in its
678 ;; save location or in a register, in either case this restores it.
680 ;; The return pops the return address (4 bytes), then we need
681 ;; to pop all the slots before the return-pc which includes the
682 ;; 4 bytes for the old-fp.
683 (inst ret (* (tn-offset return-pc) n-word-bytes))))
685 (trace-table-entry trace-table-normal)))
689 ;;; There is something of a cross-product effect with full calls.
690 ;;; Different versions are used depending on whether we know the
691 ;;; number of arguments or the name of the called function, and
692 ;;; whether we want fixed values, unknown values, or a tail call.
694 ;;; In full call, the arguments are passed creating a partial frame on
695 ;;; the stack top and storing stack arguments into that frame. On
696 ;;; entry to the callee, this partial frame is pointed to by FP.
698 ;;; This macro helps in the definition of full call VOPs by avoiding
699 ;;; code replication in defining the cross-product VOPs.
701 ;;; NAME is the name of the VOP to define.
703 ;;; NAMED is true if the first argument is an fdefinition object whose
704 ;;; definition is to be called.
706 ;;; RETURN is either :FIXED, :UNKNOWN or :TAIL:
707 ;;; -- If :FIXED, then the call is for a fixed number of values, returned in
708 ;;; the standard passing locations (passed as result operands).
709 ;;; -- If :UNKNOWN, then the result values are pushed on the stack, and the
710 ;;; result values are specified by the Start and Count as in the
711 ;;; unknown-values continuation representation.
712 ;;; -- If :TAIL, then do a tail-recursive call. No values are returned.
713 ;;; The Old-Fp and Return-PC are passed as the second and third arguments.
715 ;;; In non-tail calls, the pointer to the stack arguments is passed as
716 ;;; the last fixed argument. If Variable is false, then the passing
717 ;;; locations are passed as a more arg. Variable is true if there are
718 ;;; a variable number of arguments passed on the stack. Variable
719 ;;; cannot be specified with :TAIL return. TR variable argument call
720 ;;; is implemented separately.
722 ;;; In tail call with fixed arguments, the passing locations are
723 ;;; passed as a more arg, but there is no new-FP, since the arguments
724 ;;; have been set up in the current frame.
725 (macrolet ((define-full-call (name named return variable)
726 (aver (not (and variable (eq return :tail))))
728 ,@(when (eq return :unknown)
729 '(unknown-values-receiver)))
731 ,@(unless (eq return :tail)
732 '((new-fp :scs (any-reg) :to (:argument 1))))
734 (fun :scs (descriptor-reg control-stack)
735 :target eax :to (:argument 0))
737 ,@(when (eq return :tail)
741 ,@(unless variable '((args :more t :scs (descriptor-reg)))))
743 ,@(when (eq return :fixed)
744 '((:results (values :more t))))
746 (:save-p ,(if (eq return :tail) :compute-only t))
748 ,@(unless (or (eq return :tail) variable)
749 '((:move-args :full-call)))
753 ,@(unless (or variable (eq return :tail)) '(arg-locs))
754 ,@(unless variable '(nargs))
755 ,@(when (eq return :fixed) '(nvals)))
758 ,@(unless (or variable (eq return :tail)) '(arg-locs))
759 ,@(unless variable '(args)))
761 ;; We pass either the fdefn object (for named call) or
762 ;; the actual function object (for unnamed call) in
763 ;; EAX. With named call, closure-tramp will replace it
764 ;; with the real function and invoke the real function
765 ;; for closures. Non-closures do not need this value,
766 ;; so don't care what shows up in it.
774 ;; We pass the number of arguments in ECX.
775 (:temporary (:sc unsigned-reg :offset ecx-offset :to :eval) ecx)
777 ;; With variable call, we have to load the
778 ;; register-args out of the (new) stack frame before
779 ;; doing the call. Therefore, we have to tell the
780 ;; lifetime stuff that we need to use them.
782 (mapcar (lambda (name offset)
783 `(:temporary (:sc descriptor-reg
788 *register-arg-names* *register-arg-offsets*))
790 ,@(when (eq return :tail)
791 '((:temporary (:sc unsigned-reg
796 (:generator ,(+ (if named 5 0)
798 (if (eq return :tail) 0 10)
800 (if (eq return :unknown) 25 0))
801 (trace-table-entry trace-table-call-site)
803 ;; This has to be done before the frame pointer is
804 ;; changed! EAX stores the 'lexical environment' needed
810 ;; For variable call, compute the number of
811 ;; arguments and move some of the arguments to
814 ;; Compute the number of arguments.
815 (noise '(inst mov ecx new-fp))
816 (noise '(inst sub ecx esp-tn))
817 ;; Move the necessary args to registers,
818 ;; this moves them all even if they are
821 for name in *register-arg-names*
822 for index downfrom -1
823 do (noise `(loadw ,name new-fp ,index)))
827 (inst mov ecx (fixnumize nargs)))))
828 ,@(cond ((eq return :tail)
829 '(;; Python has figured out what frame we should
830 ;; return to so might as well use that clue.
831 ;; This seems really important to the
832 ;; implementation of things like
833 ;; (without-interrupts ...)
835 ;; dtc; Could be doing a tail call from a
836 ;; known-local-call etc in which the old-fp
837 ;; or ret-pc are in regs or in non-standard
838 ;; places. If the passing location were
839 ;; wired to the stack in standard locations
840 ;; then these moves will be un-necessary;
841 ;; this is probably best for the x86.
844 (unless (= ocfp-save-offset
846 ;; FIXME: FORMAT T for stale
847 ;; diagnostic output (several of
848 ;; them around here), ick
849 (format t "** tail-call old-fp not S0~%")
850 (move old-fp-tmp old-fp)
853 (- (1+ ocfp-save-offset)))))
854 ((any-reg descriptor-reg)
855 (format t "** tail-call old-fp in reg not S0~%")
858 (- (1+ ocfp-save-offset)))))
860 ;; For tail call, we have to push the
861 ;; return-pc so that it looks like we CALLed
862 ;; despite the fact that we are going to JMP.
863 (inst push return-pc)
866 ;; For non-tail call, we have to save our
867 ;; frame pointer and install the new frame
868 ;; pointer. We can't load stack tns after this
870 `(;; Python doesn't seem to allocate a frame
871 ;; here which doesn't leave room for the
874 ;; The variable args are on the stack and
875 ;; become the frame, but there may be <3
876 ;; args and 3 stack slots are assumed
877 ;; allocate on the call. So need to ensure
878 ;; there are at least 3 slots. This hack
881 '(inst sub esp-tn (fixnumize 3)))
884 (storew ebp-tn new-fp (- (1+ ocfp-save-offset)))
886 (move ebp-tn new-fp) ; NB - now on new stack frame.
889 (note-this-location vop :call-site)
891 (inst ,(if (eq return :tail) 'jmp 'call)
892 (make-ea :dword :base eax
894 '(- (* fdefn-raw-addr-slot
896 other-pointer-lowtag)
897 '(- (* closure-fun-slot n-word-bytes)
898 fun-pointer-lowtag))))
901 '((default-unknown-values vop values nvals)))
903 '((note-this-location vop :unknown-return)
904 (receive-unknown-values values-start nvals start count)))
906 (trace-table-entry trace-table-normal)))))
908 (define-full-call call nil :fixed nil)
909 (define-full-call call-named t :fixed nil)
910 (define-full-call multiple-call nil :unknown nil)
911 (define-full-call multiple-call-named t :unknown nil)
912 (define-full-call tail-call nil :tail nil)
913 (define-full-call tail-call-named t :tail nil)
915 (define-full-call call-variable nil :fixed t)
916 (define-full-call multiple-call-variable nil :unknown t))
918 ;;; This is defined separately, since it needs special code that BLT's
919 ;;; the arguments down. All the real work is done in the assembly
920 ;;; routine. We just set things up so that it can find what it needs.
921 (define-vop (tail-call-variable)
922 (:args (args :scs (any-reg control-stack) :target esi)
923 (function :scs (descriptor-reg control-stack) :target eax)
926 (:temporary (:sc unsigned-reg :offset esi-offset :from (:argument 0)) esi)
927 (:temporary (:sc unsigned-reg :offset eax-offset :from (:argument 1)) eax)
928 ; (:ignore ret-addr old-fp)
930 ;; Move these into the passing locations if they are not already there.
934 ;; The following assumes that the return-pc and old-fp are on the
935 ;; stack in their standard save locations - Check this.
936 (unless (and (sc-is old-fp control-stack)
937 (= (tn-offset old-fp) ocfp-save-offset))
938 (error "tail-call-variable: ocfp not on stack in standard save location?"))
939 (unless (and (sc-is ret-addr sap-stack)
940 (= (tn-offset ret-addr) return-pc-save-offset))
941 (error "tail-call-variable: ret-addr not on stack in standard save location?"))
944 ;; And jump to the assembly routine.
945 (inst jmp (make-fixup 'tail-call-variable :assembly-routine))))
947 ;;;; unknown values return
949 ;;; Return a single-value using the Unknown-Values convention. Specifically,
950 ;;; we jump to clear the stack and jump to return-pc+2.
952 ;;; We require old-fp to be in a register, because we want to reset ESP before
953 ;;; restoring EBP. If old-fp were still on the stack, it could get clobbered
956 ;;; pfw--get wired-tn conflicts sometimes if register sc specd for args
957 ;;; having problems targeting args to regs -- using temps instead.
958 (define-vop (return-single)
962 (:temporary (:sc unsigned-reg) ofp)
963 (:temporary (:sc unsigned-reg) ret)
966 (trace-table-entry trace-table-fun-epilogue)
968 ;; Clear the control stack
970 ;; Adjust the return address for the single value return.
972 ;; Restore the frame pointer.
978 ;;; Do unknown-values return of a fixed (other than 1) number of
979 ;;; values. The VALUES are required to be set up in the standard
980 ;;; passing locations. NVALS is the number of values returned.
982 ;;; Basically, we just load ECX with the number of values returned and
983 ;;; EBX with a pointer to the values, set ESP to point to the end of
984 ;;; the values, and jump directly to return-pc.
987 (return-pc :to (:eval 1))
992 ;; In the case of other than one value, we need these registers to
993 ;; tell the caller where they are and how many there are.
994 (:temporary (:sc unsigned-reg :offset ebx-offset) ebx)
995 (:temporary (:sc unsigned-reg :offset ecx-offset) ecx)
997 ;; We need to stretch the lifetime of return-pc past the argument
998 ;; registers so that we can default the argument registers without
999 ;; trashing return-pc.
1000 (:temporary (:sc unsigned-reg :offset (first *register-arg-offsets*)
1002 (:temporary (:sc unsigned-reg :offset (second *register-arg-offsets*)
1004 (:temporary (:sc unsigned-reg :offset (third *register-arg-offsets*)
1008 (trace-table-entry trace-table-fun-epilogue)
1009 ;; Establish the values pointer and values count.
1012 (inst xor ecx ecx) ; smaller
1013 (inst mov ecx (fixnumize nvals)))
1014 ;; Restore the frame pointer.
1015 (move ebp-tn old-fp)
1016 ;; Clear as much of the stack as possible, but not past the return
1018 (inst lea esp-tn (make-ea :dword :base ebx
1019 :disp (- (* (max nvals 2) n-word-bytes))))
1020 ;; Pre-default any argument register that need it.
1021 (when (< nvals register-arg-count)
1022 (let* ((arg-tns (nthcdr nvals (list a0 a1 a2)))
1023 (first (first arg-tns)))
1024 (inst mov first nil-value)
1025 (dolist (tn (cdr arg-tns))
1026 (inst mov tn first))))
1027 ;; And away we go. Except that return-pc is still on the
1028 ;; stack and we've changed the stack pointer. So we have to
1029 ;; tell it to index off of EBX instead of EBP.
1030 (cond ((zerop nvals)
1031 ;; Return popping the return address and the OCFP.
1032 (inst ret n-word-bytes))
1034 ;; Return popping the return, leaving 1 slot. Can this
1035 ;; happen, or is a single value return handled elsewhere?
1038 (inst jmp (make-ea :dword :base ebx
1039 :disp (- (* (1+ (tn-offset return-pc))
1042 (trace-table-entry trace-table-normal)))
1044 ;;; Do unknown-values return of an arbitrary number of values (passed
1045 ;;; on the stack.) We check for the common case of a single return
1046 ;;; value, and do that inline using the normal single value return
1047 ;;; convention. Otherwise, we branch off to code that calls an
1048 ;;; assembly-routine.
1050 ;;; The assembly routine takes the following args:
1051 ;;; EAX -- the return-pc to finally jump to.
1052 ;;; EBX -- pointer to where to put the values.
1053 ;;; ECX -- number of values to find there.
1054 ;;; ESI -- pointer to where to find the values.
1055 (define-vop (return-multiple)
1056 (:args (old-fp :to (:eval 1) :target old-fp-temp)
1057 (return-pc :target eax)
1058 (vals :scs (any-reg) :target esi)
1059 (nvals :scs (any-reg) :target ecx))
1061 (:temporary (:sc unsigned-reg :offset eax-offset :from (:argument 1)) eax)
1062 (:temporary (:sc unsigned-reg :offset esi-offset :from (:argument 2)) esi)
1063 (:temporary (:sc unsigned-reg :offset ecx-offset :from (:argument 3)) ecx)
1064 (:temporary (:sc unsigned-reg :offset ebx-offset :from (:eval 0)) ebx)
1065 (:temporary (:sc descriptor-reg :offset (first *register-arg-offsets*)
1066 :from (:eval 0)) a0)
1067 (:temporary (:sc unsigned-reg :from (:eval 1)) old-fp-temp)
1071 (trace-table-entry trace-table-fun-epilogue)
1072 ;; Load the return-pc.
1073 (move eax return-pc)
1074 (unless (policy node (> space speed))
1075 ;; Check for the single case.
1076 (let ((not-single (gen-label)))
1077 (inst cmp nvals (fixnumize 1))
1078 (inst jmp :ne not-single)
1080 ;; Return with one value.
1082 ;; Clear the stack. We load old-fp into a register before clearing
1084 (move old-fp-temp old-fp)
1085 (move esp-tn ebp-tn)
1086 (move ebp-tn old-fp-temp)
1087 ;; Fix the return-pc to point at the single-value entry point.
1092 ;; Nope, not the single case. Jump to the assembly routine.
1093 (emit-label not-single)))
1097 (move ebp-tn old-fp)
1098 (inst jmp (make-fixup 'return-multiple :assembly-routine))
1099 (trace-table-entry trace-table-normal)))
1103 ;;; We don't need to do anything special for regular functions.
1104 (define-vop (setup-environment)
1108 ;; Don't bother doing anything.
1111 ;;; Get the lexical environment from its passing location.
1112 (define-vop (setup-closure-environment)
1113 (:results (closure :scs (descriptor-reg)))
1118 (move closure eax-tn)))
1120 ;;; Copy a &MORE arg from the argument area to the end of the current
1121 ;;; frame. FIXED is the number of non-&MORE arguments.
1123 ;;; The tricky part is doing this without trashing any of the calling
1124 ;;; convention registers that are still needed. This vop is emitted
1125 ;;; directly after the xep-allocate frame. That means the registers
1126 ;;; are in use as follows:
1128 ;;; EAX -- The lexenv.
1129 ;;; EBX -- Available.
1130 ;;; ECX -- The total number of arguments.
1131 ;;; EDX -- The first arg.
1132 ;;; EDI -- The second arg.
1133 ;;; ESI -- The third arg.
1135 ;;; So basically, we have one register available for our use: EBX.
1137 ;;; What we can do is push the other regs onto the stack, and then
1138 ;;; restore their values by looking directly below where we put the
1140 (define-vop (copy-more-arg)
1143 ;; Avoid the copy if there are no more args.
1144 (cond ((zerop fixed)
1145 (inst jecxz just-alloc-frame))
1147 (inst cmp ecx-tn (fixnumize fixed))
1148 (inst jmp :be just-alloc-frame)))
1150 ;; Allocate the space on the stack.
1151 ;; stack = ebp - (max 3 frame-size) - (nargs - fixed)
1153 (make-ea :dword :base ebp-tn
1154 :disp (- (fixnumize fixed)
1156 (max 3 (sb-allocated-size 'stack))))))
1157 (inst sub ebx-tn ecx-tn) ; Got the new stack in ebx
1158 (inst mov esp-tn ebx-tn)
1160 ;; Now: nargs>=1 && nargs>fixed
1162 ;; Save the original count of args.
1163 (inst mov ebx-tn ecx-tn)
1165 (cond ((< fixed register-arg-count)
1166 ;; We must stop when we run out of stack args, not when we
1167 ;; run out of more args.
1168 ;; Number to copy = nargs-3
1169 (inst sub ecx-tn (fixnumize register-arg-count))
1170 ;; Everything of interest in registers.
1171 (inst jmp :be do-regs))
1173 ;; Number to copy = nargs-fixed
1174 (inst sub ecx-tn (fixnumize fixed))))
1176 ;; Save edi and esi register args.
1179 ;; Okay, we have pushed the register args. We can trash them
1182 ;; Initialize dst to be end of stack; skiping the values pushed
1184 (inst lea edi-tn (make-ea :dword :base esp-tn :disp 8))
1186 ;; Initialize src to be end of args.
1187 (inst mov esi-tn ebp-tn)
1188 (inst sub esi-tn ebx-tn)
1190 (inst shr ecx-tn word-shift) ; make word count
1191 ;; And copy the args.
1192 (inst cld) ; auto-inc ESI and EDI.
1196 ;; So now we need to restore EDI and ESI.
1203 (inst mov ecx-tn ebx-tn)
1205 ;; Here: nargs>=1 && nargs>fixed
1206 (when (< fixed register-arg-count)
1207 ;; Now we have to deposit any more args that showed up in
1211 ;; Store it relative to ebp
1212 (inst mov (make-ea :dword :base ebp-tn
1215 (max 3 (sb-allocated-size 'stack))))))
1216 (nth i *register-arg-tns*))
1219 (when (>= i register-arg-count)
1222 ;; Don't deposit any more than there are.
1224 (inst test ecx-tn ecx-tn)
1225 (inst cmp ecx-tn (fixnumize i)))
1226 (inst jmp :eq done)))
1232 (make-ea :dword :base ebp-tn
1233 :disp (- (* n-word-bytes
1234 (max 3 (sb-allocated-size 'stack))))))
1238 ;;; &MORE args are stored contiguously on the stack, starting
1239 ;;; immediately at the context pointer. The context pointer is not
1240 ;;; typed, so the lowtag is 0.
1241 (define-vop (more-arg)
1242 (:translate %more-arg)
1243 (:policy :fast-safe)
1244 (:args (object :scs (descriptor-reg) :to :result)
1245 (index :scs (any-reg) :target temp))
1246 (:arg-types * tagged-num)
1247 (:temporary (:sc unsigned-reg :from (:argument 1) :to :result) temp)
1248 (:results (value :scs (any-reg descriptor-reg)))
1253 (inst mov value (make-ea :dword :base object :index temp))))
1255 (define-vop (more-arg-c)
1256 (:translate %more-arg)
1257 (:policy :fast-safe)
1258 (:args (object :scs (descriptor-reg)))
1260 (:arg-types * (:constant (signed-byte 30)))
1261 (:results (value :scs (any-reg descriptor-reg)))
1265 (make-ea :dword :base object :disp (- (* index n-word-bytes))))))
1268 ;;; Turn more arg (context, count) into a list.
1269 (defoptimizer (%listify-rest-args stack-allocate-result) ((&rest args))
1272 (define-vop (listify-rest-args)
1273 (:translate %listify-rest-args)
1275 (:args (context :scs (descriptor-reg) :target src)
1276 (count :scs (any-reg) :target ecx))
1277 (:arg-types * tagged-num)
1278 (:temporary (:sc unsigned-reg :offset esi-offset :from (:argument 0)) src)
1279 (:temporary (:sc unsigned-reg :offset ecx-offset :from (:argument 1)) ecx)
1280 (:temporary (:sc unsigned-reg :offset eax-offset) eax)
1281 (:temporary (:sc unsigned-reg) dst)
1282 (:results (result :scs (descriptor-reg)))
1285 (let ((enter (gen-label))
1288 (stack-allocate-p (node-stack-allocate-p node)))
1291 ;; Check to see whether there are no args, and just return NIL if so.
1292 (inst mov result nil-value)
1294 (inst lea dst (make-ea :dword :index ecx :scale 2))
1295 (maybe-pseudo-atomic stack-allocate-p
1296 (allocation dst dst node stack-allocate-p)
1297 (inst lea dst (make-ea :byte :base dst :disp list-pointer-lowtag))
1298 ;; Convert the count into a raw value, so that we can use the
1299 ;; LOOP instruction.
1301 ;; Set decrement mode (successive args at lower addresses)
1303 ;; Set up the result.
1305 ;; Jump into the middle of the loop, 'cause that's were we want
1309 ;; Compute a pointer to the next cons.
1310 (inst add dst (* cons-size n-word-bytes))
1311 ;; Store a pointer to this cons in the CDR of the previous cons.
1312 (storew dst dst -1 list-pointer-lowtag)
1314 ;; Grab one value and stash it in the car of this cons.
1316 (storew eax dst 0 list-pointer-lowtag)
1317 ;; Go back for more.
1319 ;; NIL out the last cons.
1320 (storew nil-value dst 1 list-pointer-lowtag))
1322 ;; solaris requires DF being zero.
1323 #!+sunos (inst cld))))
1325 ;;; Return the location and size of the &MORE arg glob created by
1326 ;;; COPY-MORE-ARG. SUPPLIED is the total number of arguments supplied
1327 ;;; (originally passed in ECX). FIXED is the number of non-rest
1330 ;;; We must duplicate some of the work done by COPY-MORE-ARG, since at
1331 ;;; that time the environment is in a pretty brain-damaged state,
1332 ;;; preventing this info from being returned as values. What we do is
1333 ;;; compute supplied - fixed, and return a pointer that many words
1334 ;;; below the current stack top.
1335 (define-vop (more-arg-context)
1336 (:policy :fast-safe)
1337 (:translate sb!c::%more-arg-context)
1338 (:args (supplied :scs (any-reg) :target count))
1339 (:arg-types positive-fixnum (:constant fixnum))
1341 (:results (context :scs (descriptor-reg))
1342 (count :scs (any-reg)))
1343 (:result-types t tagged-num)
1344 (:note "more-arg-context")
1346 (move count supplied)
1347 ;; SP at this point points at the last arg pushed.
1348 ;; Point to the first more-arg, not above it.
1349 (inst lea context (make-ea :dword :base esp-tn
1350 :index count :scale 1
1351 :disp (- (+ (fixnumize fixed) 4))))
1352 (unless (zerop fixed)
1353 (inst sub count (fixnumize fixed)))))
1355 ;;; Signal wrong argument count error if NARGS isn't equal to COUNT.
1356 (define-vop (verify-arg-count)
1357 (:policy :fast-safe)
1358 (:translate sb!c::%verify-arg-count)
1359 (:args (nargs :scs (any-reg)))
1360 (:arg-types positive-fixnum (:constant t))
1363 (:save-p :compute-only)
1366 (generate-error-code vop invalid-arg-count-error nargs)))
1368 (inst test nargs nargs) ; smaller instruction
1369 (inst cmp nargs (fixnumize count)))
1370 (inst jmp :ne err-lab))))
1372 ;;; Various other error signallers.
1373 (macrolet ((def (name error translate &rest args)
1374 `(define-vop (,name)
1376 `((:policy :fast-safe)
1377 (:translate ,translate)))
1378 (:args ,@(mapcar (lambda (arg)
1379 `(,arg :scs (any-reg descriptor-reg)))
1382 (:save-p :compute-only)
1384 (error-call vop ,error ,@args)))))
1385 (def arg-count-error invalid-arg-count-error
1386 sb!c::%arg-count-error nargs)
1387 (def type-check-error object-not-type-error sb!c::%type-check-error
1389 (def layout-invalid-error layout-invalid-error sb!c::%layout-invalid-error
1391 (def odd-key-args-error odd-key-args-error
1392 sb!c::%odd-key-args-error)
1393 (def unknown-key-arg-error unknown-key-arg-error
1394 sb!c::%unknown-key-arg-error key)
1395 (def nil-fun-returned-error nil-fun-returned-error nil fun))