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-argument-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 ;;; Similar to Make-Return-PC-Passing-Location, but makes a location
35 ;;; 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 ;;; wire to the stack?
52 (!def-vm-support-routine make-old-fp-save-location (env)
53 (physenv-debug-live-tn (make-wired-tn *fixnum-primitive-type*
54 control-stack-sc-number
58 (!def-vm-support-routine make-return-pc-save-location (env)
59 (physenv-debug-live-tn
60 (make-wired-tn (primitive-type-or-lose 'system-area-pointer)
61 sap-stack-sc-number return-pc-save-offset)
64 ;;; Make a TN for the standard argument count passing location. We only
65 ;;; need to make the standard location, since a count is never passed when we
66 ;;; are using non-standard conventions.
67 (!def-vm-support-routine make-argument-count-location ()
68 (make-wired-tn *fixnum-primitive-type* any-reg-sc-number ecx-offset))
70 ;;; Make a TN to hold the number-stack frame pointer. This is allocated
71 ;;; once per component, and is component-live.
72 (!def-vm-support-routine make-nfp-tn ()
73 (make-restricted-tn *fixnum-primitive-type* ignore-me-sc-number))
75 (!def-vm-support-routine make-stack-pointer-tn ()
76 (make-normal-tn *fixnum-primitive-type*))
78 (!def-vm-support-routine make-number-stack-pointer-tn ()
79 (make-restricted-tn *fixnum-primitive-type* ignore-me-sc-number))
81 ;;; Return a list of TNs that can be used to represent an unknown-values
82 ;;; continuation within a function.
83 (!def-vm-support-routine make-unknown-values-locations ()
84 (list (make-stack-pointer-tn)
85 (make-normal-tn *fixnum-primitive-type*)))
87 ;;; This function is called by the ENTRY-ANALYZE phase, allowing
88 ;;; VM-dependent initialization of the IR2-COMPONENT structure. We
89 ;;; push placeholder entries in the CONSTANTS to leave room for
90 ;;; additional noise in the code object header.
91 (!def-vm-support-routine select-component-format (component)
92 (declare (type component component))
93 ;; The 1+ here is because for the x86 the first constant is a
94 ;; pointer to a list of fixups, or NIL if the code object has none.
95 ;; (If I understand correctly, the fixups are needed at GC copy
96 ;; time because the X86 code isn't relocatable.)
98 ;; KLUDGE: It'd be cleaner to have the fixups entry be a named
99 ;; element of the CODE (aka component) primitive object. However,
100 ;; it's currently a large, tricky, error-prone chore to change
101 ;; the layout of any primitive object, so for the foreseeable future
102 ;; we'll just live with this ugliness. -- WHN 2002-01-02
103 (dotimes (i (1+ code-constants-offset))
104 (vector-push-extend nil
105 (ir2-component-constants (component-info component))))
110 ;;; This is used for setting up the Old-FP in local call.
111 (define-vop (current-fp)
112 (:results (val :scs (any-reg control-stack)))
116 ;;; We don't have a separate NFP, so we don't need to do anything here.
117 (define-vop (compute-old-nfp)
123 (define-vop (xep-allocate-frame)
124 (:info start-lab copy-more-arg-follows)
127 (align n-lowtag-bits)
128 (trace-table-entry trace-table-function-prologue)
129 (emit-label start-lab)
130 ;; Skip space for the function header.
131 (inst simple-fun-header-word)
132 (dotimes (i (1- simple-fun-code-offset))
135 ;; The start of the actual code.
136 ;; Save the return-pc.
137 (popw ebp-tn (- (1+ return-pc-save-offset)))
139 ;; If copy-more-arg follows it will allocate the correct stack
140 ;; size. The stack is not allocated first here as this may expose
141 ;; args on the stack if they take up more space than the frame!
142 (unless copy-more-arg-follows
143 ;; The args fit within the frame so just allocate the frame.
145 (make-ea :dword :base ebp-tn
146 :disp (- (* n-word-bytes
147 (max 3 (sb-allocated-size 'stack)))))))
149 (trace-table-entry trace-table-normal)))
151 ;;; This is emitted directly before either a known-call-local, call-local,
152 ;;; or a multiple-call-local. All it does is allocate stack space for the
153 ;;; callee (who has the same size stack as us).
154 (define-vop (allocate-frame)
155 (:results (res :scs (any-reg control-stack))
161 (inst sub esp-tn (* n-word-bytes (sb-allocated-size 'stack)))))
163 ;;; Allocate a partial frame for passing stack arguments in a full
164 ;;; call. NARGS is the number of arguments passed. We allocate at
165 ;;; least 3 slots, because the XEP noise is going to want to use them
166 ;;; before it can extend the stack.
167 (define-vop (allocate-full-call-frame)
169 (:results (res :scs (any-reg control-stack)))
172 (inst sub esp-tn (* (max nargs 3) n-word-bytes))))
174 ;;; Emit code needed at the return-point from an unknown-values call
175 ;;; for a fixed number of values. Values is the head of the TN-Ref
176 ;;; list for the locations that the values are to be received into.
177 ;;; Nvals is the number of values that are to be received (should
178 ;;; equal the length of Values).
180 ;;; Move-Temp is a Descriptor-Reg TN used as a temporary.
182 ;;; This code exploits the fact that in the unknown-values convention,
183 ;;; a single value return returns at the return PC + 2, whereas a
184 ;;; return of other than one value returns directly at the return PC.
186 ;;; If 0 or 1 values are expected, then we just emit an instruction to
187 ;;; reset the SP (which will only be executed when other than 1 value
190 ;;; In the general case we have to do three things:
191 ;;; -- Default unsupplied register values. This need only be done
192 ;;; when a single value is returned, since register values are
193 ;;; defaulted by the called in the non-single case.
194 ;;; -- Default unsupplied stack values. This needs to be done whenever
195 ;;; there are stack values.
196 ;;; -- Reset SP. This must be done whenever other than 1 value is
197 ;;; returned, regardless of the number of values desired.
198 (defun default-unknown-values (vop values nvals)
199 (declare (type (or tn-ref null) values)
200 (type unsigned-byte nvals))
203 (note-this-location vop :single-value-return)
204 (inst mov esp-tn ebx-tn))
205 ((<= nvals register-arg-count)
206 (let ((regs-defaulted (gen-label)))
207 (note-this-location vop :unknown-return)
208 (inst jmp-short regs-defaulted)
209 ;; Default the unsuppled registers.
210 (let* ((2nd-tn-ref (tn-ref-across values))
211 (2nd-tn (tn-ref-tn 2nd-tn-ref)))
212 (inst mov 2nd-tn nil-value)
215 for tn-ref = (tn-ref-across 2nd-tn-ref)
216 then (tn-ref-across tn-ref)
217 for count from 2 below register-arg-count
218 do (inst mov (tn-ref-tn tn-ref) 2nd-tn))))
219 (inst mov ebx-tn esp-tn)
220 (emit-label regs-defaulted)
221 (inst mov esp-tn ebx-tn)))
223 ;; The number of bytes depends on the relative jump instructions.
224 ;; Best case is 31+(n-3)*14, worst case is 35+(n-3)*18. For
225 ;; NVALS=6 that is 73/89 bytes, and for NVALS=7 that is 87/107
226 ;; bytes which is likely better than using the blt below.
227 (let ((regs-defaulted (gen-label))
228 (defaulting-done (gen-label))
229 (default-stack-slots (gen-label)))
230 (note-this-location vop :unknown-return)
231 ;; Branch off to the MV case.
232 (inst jmp-short regs-defaulted)
233 ;; Do the single value case.
234 ;; Default the register args
235 (inst mov eax-tn nil-value)
237 (val (tn-ref-across values) (tn-ref-across val)))
238 ((= i (min nvals register-arg-count)))
239 (inst mov (tn-ref-tn val) eax-tn))
241 ;; Fake other registers so it looks like we returned with all the
242 ;; registers filled in.
245 (inst jmp default-stack-slots)
247 (emit-label regs-defaulted)
249 (inst mov eax-tn nil-value)
250 (storew edx-tn ebx-tn -1)
251 (collect ((defaults))
252 (do ((i register-arg-count (1+ i))
253 (val (do ((i 0 (1+ i))
254 (val values (tn-ref-across val)))
255 ((= i register-arg-count) val))
256 (tn-ref-across val)))
258 (let ((default-lab (gen-label))
259 (tn (tn-ref-tn val)))
260 (defaults (cons default-lab tn))
262 (inst cmp ecx-tn (fixnumize i))
263 (inst jmp :be default-lab)
264 (loadw edx-tn ebx-tn (- (1+ i)))
265 (inst mov tn edx-tn)))
267 (emit-label defaulting-done)
268 (loadw edx-tn ebx-tn -1)
271 (let ((defaults (defaults)))
273 (assemble (*elsewhere*)
274 (trace-table-entry trace-table-function-prologue)
275 (emit-label default-stack-slots)
276 (dolist (default defaults)
277 (emit-label (car default))
278 (inst mov (cdr default) eax-tn))
279 (inst jmp defaulting-done)
280 (trace-table-entry trace-table-normal)))))))
282 ;; 91 bytes for this branch.
283 (let ((regs-defaulted (gen-label))
284 (restore-edi (gen-label))
285 (no-stack-args (gen-label))
286 (default-stack-vals (gen-label))
287 (count-okay (gen-label)))
288 (note-this-location vop :unknown-return)
289 ;; Branch off to the MV case.
290 (inst jmp-short regs-defaulted)
292 ;; Default the register args, and set up the stack as if we
293 ;; entered the MV return point.
294 (inst mov ebx-tn esp-tn)
296 (inst mov edi-tn nil-value)
298 (inst mov esi-tn edi-tn)
299 ;; Compute a pointer to where to put the [defaulted] stack values.
300 (emit-label no-stack-args)
302 (make-ea :dword :base ebp-tn
303 :disp (* (- (1+ register-arg-count)) n-word-bytes)))
304 ;; Load EAX with NIL so we can quickly store it, and set up
305 ;; stuff for the loop.
306 (inst mov eax-tn nil-value)
308 (inst mov ecx-tn (- nvals register-arg-count))
309 ;; Jump into the default loop.
310 (inst jmp default-stack-vals)
312 ;; The regs are defaulted. We need to copy any stack arguments,
313 ;; and then default the remaining stack arguments.
314 (emit-label regs-defaulted)
316 (storew edi-tn ebx-tn (- (1+ 1)))
317 ;; Compute the number of stack arguments, and if it's zero or
318 ;; less, don't copy any stack arguments.
319 (inst sub ecx-tn (fixnumize register-arg-count))
320 (inst jmp :le no-stack-args)
322 ;; Throw away any unwanted args.
323 (inst cmp ecx-tn (fixnumize (- nvals register-arg-count)))
324 (inst jmp :be count-okay)
325 (inst mov ecx-tn (fixnumize (- nvals register-arg-count)))
326 (emit-label count-okay)
327 ;; Save the number of stack values.
328 (inst mov eax-tn ecx-tn)
329 ;; Compute a pointer to where the stack args go.
331 (make-ea :dword :base ebp-tn
332 :disp (* (- (1+ register-arg-count)) n-word-bytes)))
333 ;; Save ESI, and compute a pointer to where the args come from.
334 (storew esi-tn ebx-tn (- (1+ 2)))
336 (make-ea :dword :base ebx-tn
337 :disp (* (- (1+ register-arg-count)) n-word-bytes)))
339 (inst shr ecx-tn word-shift) ; make word count
344 (loadw esi-tn ebx-tn (- (1+ 2)))
345 ;; Now we have to default the remaining args. Find out how many.
346 (inst sub eax-tn (fixnumize (- nvals register-arg-count)))
348 ;; If none, then just blow out of here.
349 (inst jmp :le restore-edi)
350 (inst mov ecx-tn eax-tn)
351 (inst shr ecx-tn word-shift) ; word count
352 ;; Load EAX with NIL for fast storing.
353 (inst mov eax-tn nil-value)
355 (emit-label default-stack-vals)
358 ;; Restore EDI, and reset the stack.
359 (emit-label restore-edi)
360 (loadw edi-tn ebx-tn (- (1+ 1)))
361 (inst mov esp-tn ebx-tn))))
364 ;;;; unknown values receiving
366 ;;; Emit code needed at the return point for an unknown-values call
367 ;;; for an arbitrary number of values.
369 ;;; We do the single and non-single cases with no shared code: there
370 ;;; doesn't seem to be any potential overlap, and receiving a single
371 ;;; value is more important efficiency-wise.
373 ;;; When there is a single value, we just push it on the stack,
374 ;;; returning the old SP and 1.
376 ;;; When there is a variable number of values, we move all of the
377 ;;; argument registers onto the stack, and return ARGS and NARGS.
379 ;;; ARGS and NARGS are TNs wired to the named locations. We must
380 ;;; explicitly allocate these TNs, since their lifetimes overlap with
381 ;;; the results start and count. (Also, it's nice to be able to target
383 (defun receive-unknown-values (args nargs start count)
384 (declare (type tn args nargs start count))
385 (let ((variable-values (gen-label))
387 (inst jmp-short variable-values)
389 (inst mov start esp-tn)
390 (inst push (first *register-arg-tns*))
391 (inst mov count (fixnumize 1))
394 (emit-label variable-values)
395 ;; dtc: this writes the registers onto the stack even if they are
396 ;; not needed, only the number specified in ecx are used and have
397 ;; stack allocated to them. No harm is done.
399 for arg in *register-arg-tns*
401 do (storew arg args i))
408 ;;; VOP that can be inherited by unknown values receivers. The main thing this
409 ;;; handles is allocation of the result temporaries.
410 (define-vop (unknown-values-receiver)
411 (:temporary (:sc descriptor-reg :offset ebx-offset
412 :from :eval :to (:result 0))
414 (:temporary (:sc any-reg :offset ecx-offset
415 :from :eval :to (:result 1))
417 (:results (start :scs (any-reg control-stack))
418 (count :scs (any-reg control-stack))))
420 ;;;; local call with unknown values convention return
422 ;;; Non-TR local call for a fixed number of values passed according to
423 ;;; the unknown values convention.
425 ;;; FP is the frame pointer in install before doing the call.
427 ;;; NFP would be the number-stack frame pointer if we had a separate
430 ;;; Args are the argument passing locations, which are specified only
431 ;;; to terminate their lifetimes in the caller.
433 ;;; VALUES are the return value locations (wired to the standard
434 ;;; passing locations). NVALS is the number of values received.
436 ;;; Save is the save info, which we can ignore since saving has been
439 ;;; TARGET is a continuation pointing to the start of the called
441 (define-vop (call-local)
445 (:results (values :more t))
447 (:move-args :local-call)
448 (:info arg-locs callee target nvals)
450 (:ignore nfp arg-locs args #+nil callee)
452 (trace-table-entry trace-table-call-site)
455 (let ((ret-tn (callee-return-pc-tn callee)))
457 (format t "*call-local ~S; tn-kind ~S; tn-save-tn ~S; its tn-kind ~S~%"
458 ret-tn (sb!c::tn-kind ret-tn) (sb!c::tn-save-tn ret-tn)
459 (sb!c::tn-kind (sb!c::tn-save-tn ret-tn)))
461 ;; Is the return-pc on the stack or in a register?
464 #+nil (format t "*call-local: ret-tn on stack; offset=~S~%"
466 (storew (make-fixup nil :code-object return)
467 ebp-tn (- (1+ (tn-offset ret-tn)))))
469 (inst lea ret-tn (make-fixup nil :code-object return)))))
471 (note-this-location vop :call-site)
474 (default-unknown-values vop values nvals)
475 (trace-table-entry trace-table-normal)))
477 ;;; Non-TR local call for a variable number of return values passed according
478 ;;; to the unknown values convention. The results are the start of the values
479 ;;; glob and the number of values received.
480 (define-vop (multiple-call-local unknown-values-receiver)
485 (:move-args :local-call)
486 (:info save callee target)
487 (:ignore args save nfp #+nil callee)
490 (trace-table-entry trace-table-call-site)
493 (let ((ret-tn (callee-return-pc-tn callee)))
495 (format t "*multiple-call-local ~S; tn-kind ~S; tn-save-tn ~S; its tn-kind ~S~%"
496 ret-tn (sb!c::tn-kind ret-tn) (sb!c::tn-save-tn ret-tn)
497 (sb!c::tn-kind (sb!c::tn-save-tn ret-tn)))
499 ;; Is the return-pc on the stack or in a register?
502 #+nil (format t "*multiple-call-local: ret-tn on stack; offset=~S~%"
505 (storew (make-fixup nil :code-object return)
506 ebp-tn (- (1+ (tn-offset ret-tn)))))
509 (inst lea ret-tn (make-fixup nil :code-object return)))))
511 (note-this-location vop :call-site)
514 (note-this-location vop :unknown-return)
515 (receive-unknown-values values-start nvals start count)
516 (trace-table-entry trace-table-normal)))
518 ;;;; local call with known values return
520 ;;; Non-TR local call with known return locations. Known-value return
521 ;;; works just like argument passing in local call.
523 ;;; Note: we can't use normal load-tn allocation for the fixed args,
524 ;;; since all registers may be tied up by the more operand. Instead,
525 ;;; we use MAYBE-LOAD-STACK-TN.
526 (define-vop (known-call-local)
530 (:results (res :more t))
531 (:move-args :local-call)
533 (:info save callee target)
534 (:ignore args res save nfp #+nil callee)
537 (trace-table-entry trace-table-call-site)
540 (let ((ret-tn (callee-return-pc-tn callee)))
543 (format t "*known-call-local ~S; tn-kind ~S; tn-save-tn ~S; its tn-kind ~S~%"
544 ret-tn (sb!c::tn-kind ret-tn) (sb!c::tn-save-tn ret-tn)
545 (sb!c::tn-kind (sb!c::tn-save-tn ret-tn)))
547 ;; Is the return-pc on the stack or in a register?
550 #+nil (format t "*known-call-local: ret-tn on stack; offset=~S~%"
553 (storew (make-fixup nil :code-object return)
554 ebp-tn (- (1+ (tn-offset ret-tn)))))
557 (inst lea ret-tn (make-fixup nil :code-object return)))))
559 (note-this-location vop :call-site)
562 (note-this-location vop :known-return)
563 (trace-table-entry trace-table-normal)))
565 ;;; Return from known values call. We receive the return locations as
566 ;;; arguments to terminate their lifetimes in the returning function. We
567 ;;; restore FP and CSP and jump to the Return-PC.
569 ;;; We can assume we know exactly where old-fp and return-pc are because
570 ;;; make-old-fp-save-location and make-return-pc-save-location always
571 ;;; return the same place.
573 (define-vop (known-return)
575 (return-pc :scs (any-reg immediate-stack) :target rpc)
577 (:move-args :known-return)
579 (:temporary (:sc unsigned-reg :from (:argument 1)) rpc)
580 (:ignore val-locs vals)
583 (trace-table-entry trace-table-function-epilogue)
584 ;; Save the return-pc in a register 'cause the frame-pointer is
585 ;; going away. Note this not in the usual stack location so we
588 ;; Restore the stack.
590 ;; Restore the old fp. We know OLD-FP is going to be in its stack
591 ;; save slot, which is a different frame that than this one,
592 ;; so we don't have to worry about having just cleared
593 ;; most of the stack.
596 (trace-table-entry trace-table-normal)))
598 ;;; From Douglas Crosher
599 ;;; Return from known values call. We receive the return locations as
600 ;;; arguments to terminate their lifetimes in the returning function. We
601 ;;; restore FP and CSP and jump to the Return-PC.
603 ;;; The old-fp may be either in a register or on the stack in its
604 ;;; standard save locations - slot 0.
606 ;;; The return-pc may be in a register or on the stack in any slot.
607 (define-vop (known-return)
611 (:move-args :known-return)
613 (:ignore val-locs vals)
616 (trace-table-entry trace-table-function-epilogue)
618 #+nil (format t "*known-return: old-fp ~S, tn-kind ~S; ~S ~S~%"
619 old-fp (sb!c::tn-kind old-fp) (sb!c::tn-save-tn old-fp)
620 (sb!c::tn-kind (sb!c::tn-save-tn old-fp)))
622 #+nil (format t "*known-return: return-pc ~S, tn-kind ~S; ~S ~S~%"
623 return-pc (sb!c::tn-kind return-pc) (sb!c::tn-save-tn return-pc)
624 (sb!c::tn-kind (sb!c::tn-save-tn return-pc)))
626 ;; return-pc may be either in a register or on the stack.
632 #+nil (format t "*known-return: old-fp ~S on stack; offset=~S~%"
633 old-fp (tn-offset old-fp))
635 (cond ((zerop (tn-offset old-fp))
636 ;; Zot all of the stack except for the old-fp.
637 (inst lea esp-tn (make-ea :dword :base ebp-tn
638 :disp (- (* (1+ ocfp-save-offset)
640 ;; Restore the old fp from its save location on the stack,
641 ;; and zot the stack.
645 (cerror "Continue any-way"
646 "VOP return-local doesn't work if old-fp (in slot %s) is not in slot 0"
647 (tn-offset old-fp)))))
649 ((any-reg descriptor-reg)
650 ;; Zot all the stack.
652 ;; Restore the old-fp.
653 (move ebp-tn old-fp)))
655 ;; Return; return-pc is in a register.
656 (inst jmp return-pc))
660 #+nil (format t "*known-return: return-pc ~S on stack; offset=~S~%"
661 return-pc (tn-offset return-pc))
663 ;; Zot all of the stack except for the old-fp and return-pc.
665 (make-ea :dword :base ebp-tn
666 :disp (- (* (1+ (tn-offset return-pc)) n-word-bytes))))
667 ;; Restore the old fp. old-fp may be either on the stack in its
668 ;; save location or in a register, in either case this restores it.
670 ;; The return pops the return address (4 bytes), then we need
671 ;; to pop all the slots before the return-pc which includes the
672 ;; 4 bytes for the old-fp.
673 (inst ret (* (tn-offset return-pc) n-word-bytes))))
675 (trace-table-entry trace-table-normal)))
679 ;;; There is something of a cross-product effect with full calls.
680 ;;; Different versions are used depending on whether we know the
681 ;;; number of arguments or the name of the called function, and
682 ;;; whether we want fixed values, unknown values, or a tail call.
684 ;;; In full call, the arguments are passed creating a partial frame on
685 ;;; the stack top and storing stack arguments into that frame. On
686 ;;; entry to the callee, this partial frame is pointed to by FP.
688 ;;; This macro helps in the definition of full call VOPs by avoiding
689 ;;; code replication in defining the cross-product VOPs.
691 ;;; NAME is the name of the VOP to define.
693 ;;; NAMED is true if the first argument is an fdefinition object whose
694 ;;; definition is to be called.
696 ;;; RETURN is either :FIXED, :UNKNOWN or :TAIL:
697 ;;; -- If :FIXED, then the call is for a fixed number of values, returned in
698 ;;; the standard passing locations (passed as result operands).
699 ;;; -- If :UNKNOWN, then the result values are pushed on the stack, and the
700 ;;; result values are specified by the Start and Count as in the
701 ;;; unknown-values continuation representation.
702 ;;; -- If :TAIL, then do a tail-recursive call. No values are returned.
703 ;;; The Old-Fp and Return-PC are passed as the second and third arguments.
705 ;;; In non-tail calls, the pointer to the stack arguments is passed as
706 ;;; the last fixed argument. If Variable is false, then the passing
707 ;;; locations are passed as a more arg. Variable is true if there are
708 ;;; a variable number of arguments passed on the stack. Variable
709 ;;; cannot be specified with :Tail return. TR variable argument call
710 ;;; is implemented separately.
712 ;;; In tail call with fixed arguments, the passing locations are
713 ;;; passed as a more arg, but there is no new-FP, since the arguments
714 ;;; have been set up in the current frame.
715 (macrolet ((define-full-call (name named return variable)
716 (aver (not (and variable (eq return :tail))))
718 ,@(when (eq return :unknown)
719 '(unknown-values-receiver)))
721 ,@(unless (eq return :tail)
722 '((new-fp :scs (any-reg) :to (:argument 1))))
724 (fun :scs (descriptor-reg control-stack)
725 :target eax :to (:argument 0))
727 ,@(when (eq return :tail)
731 ,@(unless variable '((args :more t :scs (descriptor-reg)))))
733 ,@(when (eq return :fixed)
734 '((:results (values :more t))))
736 (:save-p ,(if (eq return :tail) :compute-only t))
738 ,@(unless (or (eq return :tail) variable)
739 '((:move-args :full-call)))
743 ,@(unless (or variable (eq return :tail)) '(arg-locs))
744 ,@(unless variable '(nargs))
745 ,@(when (eq return :fixed) '(nvals)))
748 ,@(unless (or variable (eq return :tail)) '(arg-locs))
749 ,@(unless variable '(args)))
751 ;; We pass either the fdefn object (for named call) or
752 ;; the actual function object (for unnamed call) in
753 ;; EAX. With named call, closure-tramp will replace it
754 ;; with the real function and invoke the real function
755 ;; for closures. Non-closures do not need this value,
756 ;; so don't care what shows up in it.
764 ;; We pass the number of arguments in ECX.
765 (:temporary (:sc unsigned-reg :offset ecx-offset :to :eval) ecx)
767 ;; With variable call, we have to load the
768 ;; register-args out of the (new) stack frame before
769 ;; doing the call. Therefore, we have to tell the
770 ;; lifetime stuff that we need to use them.
772 (mapcar (lambda (name offset)
773 `(:temporary (:sc descriptor-reg
778 *register-arg-names* *register-arg-offsets*))
780 ,@(when (eq return :tail)
781 '((:temporary (:sc unsigned-reg
786 (:generator ,(+ (if named 5 0)
788 (if (eq return :tail) 0 10)
790 (if (eq return :unknown) 25 0))
791 (trace-table-entry trace-table-call-site)
793 ;; This has to be done before the frame pointer is
794 ;; changed! EAX stores the 'lexical environment' needed
800 ;; For variable call, compute the number of
801 ;; arguments and move some of the arguments to
804 ;; Compute the number of arguments.
805 (noise '(inst mov ecx new-fp))
806 (noise '(inst sub ecx esp-tn))
807 ;; Move the necessary args to registers,
808 ;; this moves them all even if they are
811 for name in *register-arg-names*
812 for index downfrom -1
813 do (noise `(loadw ,name new-fp ,index)))
817 (inst mov ecx (fixnumize nargs)))))
818 ,@(cond ((eq return :tail)
819 '(;; Python has figured out what frame we should
820 ;; return to so might as well use that clue.
821 ;; This seems really important to the
822 ;; implementation of things like
823 ;; (without-interrupts ...)
825 ;; dtc; Could be doing a tail call from a
826 ;; known-local-call etc in which the old-fp
827 ;; or ret-pc are in regs or in non-standard
828 ;; places. If the passing location were
829 ;; wired to the stack in standard locations
830 ;; then these moves will be un-necessary;
831 ;; this is probably best for the x86.
834 (unless (= ocfp-save-offset
836 ;; FIXME: FORMAT T for stale
837 ;; diagnostic output (several of
838 ;; them around here), ick
839 (format t "** tail-call old-fp not S0~%")
840 (move old-fp-tmp old-fp)
843 (- (1+ ocfp-save-offset)))))
844 ((any-reg descriptor-reg)
845 (format t "** tail-call old-fp in reg not S0~%")
848 (- (1+ ocfp-save-offset)))))
850 ;; For tail call, we have to push the
851 ;; return-pc so that it looks like we CALLed
852 ;; despite the fact that we are going to JMP.
853 (inst push return-pc)
856 ;; For non-tail call, we have to save our
857 ;; frame pointer and install the new frame
858 ;; pointer. We can't load stack tns after this
860 `(;; Python doesn't seem to allocate a frame
861 ;; here which doesn't leave room for the
864 ;; The variable args are on the stack and
865 ;; become the frame, but there may be <3
866 ;; args and 3 stack slots are assumed
867 ;; allocate on the call. So need to ensure
868 ;; there are at least 3 slots. This hack
871 '(inst sub esp-tn (fixnumize 3)))
874 (storew ebp-tn new-fp (- (1+ ocfp-save-offset)))
876 (move ebp-tn new-fp) ; NB - now on new stack frame.
879 (note-this-location vop :call-site)
881 (inst ,(if (eq return :tail) 'jmp 'call)
882 (make-ea :dword :base eax
884 '(- (* fdefn-raw-addr-slot
886 other-pointer-lowtag)
887 '(- (* closure-fun-slot n-word-bytes)
888 fun-pointer-lowtag))))
891 '((default-unknown-values vop values nvals)))
893 '((note-this-location vop :unknown-return)
894 (receive-unknown-values values-start nvals start count)))
896 (trace-table-entry trace-table-normal)))))
898 (define-full-call call nil :fixed nil)
899 (define-full-call call-named t :fixed nil)
900 (define-full-call multiple-call nil :unknown nil)
901 (define-full-call multiple-call-named t :unknown nil)
902 (define-full-call tail-call nil :tail nil)
903 (define-full-call tail-call-named t :tail nil)
905 (define-full-call call-variable nil :fixed t)
906 (define-full-call multiple-call-variable nil :unknown t))
908 ;;; This is defined separately, since it needs special code that BLT's
909 ;;; the arguments down. All the real work is done in the assembly
910 ;;; routine. We just set things up so that it can find what it needs.
911 (define-vop (tail-call-variable)
912 (:args (args :scs (any-reg control-stack) :target esi)
913 (function :scs (descriptor-reg control-stack) :target eax)
916 (:temporary (:sc unsigned-reg :offset esi-offset :from (:argument 0)) esi)
917 (:temporary (:sc unsigned-reg :offset eax-offset :from (:argument 1)) eax)
918 ; (:ignore ret-addr old-fp)
920 ;; Move these into the passing locations if they are not already there.
924 ;; The following assumes that the return-pc and old-fp are on the
925 ;; stack in their standard save locations - Check this.
926 (unless (and (sc-is old-fp control-stack)
927 (= (tn-offset old-fp) ocfp-save-offset))
928 (error "tail-call-variable: ocfp not on stack in standard save location?"))
929 (unless (and (sc-is ret-addr sap-stack)
930 (= (tn-offset ret-addr) return-pc-save-offset))
931 (error "tail-call-variable: ret-addr not on stack in standard save location?"))
934 ;; And jump to the assembly routine.
935 (inst jmp (make-fixup 'tail-call-variable :assembly-routine))))
937 ;;;; unknown values return
939 ;;; Return a single-value using the Unknown-Values convention. Specifically,
940 ;;; we jump to clear the stack and jump to return-pc+2.
942 ;;; We require old-fp to be in a register, because we want to reset ESP before
943 ;;; restoring EBP. If old-fp were still on the stack, it could get clobbered
946 ;;; pfw--get wired-tn conflicts sometimes if register sc specd for args
947 ;;; having problems targeting args to regs -- using temps instead.
948 (define-vop (return-single)
952 (:temporary (:sc unsigned-reg) ofp)
953 (:temporary (:sc unsigned-reg) ret)
956 (trace-table-entry trace-table-function-epilogue)
958 ;; Clear the control stack
960 ;; Adjust the return address for the single value return.
962 ;; Restore the frame pointer.
968 ;;; Do unknown-values return of a fixed (other than 1) number of
969 ;;; values. The VALUES are required to be set up in the standard
970 ;;; passing locations. NVALS is the number of values returned.
972 ;;; Basically, we just load ECX with the number of values returned and
973 ;;; EBX with a pointer to the values, set ESP to point to the end of
974 ;;; the values, and jump directly to return-pc.
977 (return-pc :to (:eval 1))
982 ;; In the case of other than one value, we need these registers to
983 ;; tell the caller where they are and how many there are.
984 (:temporary (:sc unsigned-reg :offset ebx-offset) ebx)
985 (:temporary (:sc unsigned-reg :offset ecx-offset) ecx)
987 ;; We need to stretch the lifetime of return-pc past the argument
988 ;; registers so that we can default the argument registers without
989 ;; trashing return-pc.
990 (:temporary (:sc unsigned-reg :offset (first *register-arg-offsets*)
992 (:temporary (:sc unsigned-reg :offset (second *register-arg-offsets*)
994 (:temporary (:sc unsigned-reg :offset (third *register-arg-offsets*)
998 (trace-table-entry trace-table-function-epilogue)
999 ;; Establish the values pointer and values count.
1002 (inst xor ecx ecx) ; smaller
1003 (inst mov ecx (fixnumize nvals)))
1004 ;; Restore the frame pointer.
1005 (move ebp-tn old-fp)
1006 ;; Clear as much of the stack as possible, but not past the return
1008 (inst lea esp-tn (make-ea :dword :base ebx
1009 :disp (- (* (max nvals 2) n-word-bytes))))
1010 ;; Pre-default any argument register that need it.
1011 (when (< nvals register-arg-count)
1012 (let* ((arg-tns (nthcdr nvals (list a0 a1 a2)))
1013 (first (first arg-tns)))
1014 (inst mov first nil-value)
1015 (dolist (tn (cdr arg-tns))
1016 (inst mov tn first))))
1017 ;; And away we go. Except that return-pc is still on the
1018 ;; stack and we've changed the stack pointer. So we have to
1019 ;; tell it to index off of EBX instead of EBP.
1020 (cond ((zerop nvals)
1021 ;; Return popping the return address and the OCFP.
1022 (inst ret n-word-bytes))
1024 ;; Return popping the return, leaving 1 slot. Can this
1025 ;; happen, or is a single value return handled elsewhere?
1028 (inst jmp (make-ea :dword :base ebx
1029 :disp (- (* (1+ (tn-offset return-pc))
1032 (trace-table-entry trace-table-normal)))
1034 ;;; Do unknown-values return of an arbitrary number of values (passed
1035 ;;; on the stack.) We check for the common case of a single return
1036 ;;; value, and do that inline using the normal single value return
1037 ;;; convention. Otherwise, we branch off to code that calls an
1038 ;;; assembly-routine.
1040 ;;; The assembly routine takes the following args:
1041 ;;; EAX -- the return-pc to finally jump to.
1042 ;;; EBX -- pointer to where to put the values.
1043 ;;; ECX -- number of values to find there.
1044 ;;; ESI -- pointer to where to find the values.
1045 (define-vop (return-multiple)
1046 (:args (old-fp :to (:eval 1) :target old-fp-temp)
1047 (return-pc :target eax)
1048 (vals :scs (any-reg) :target esi)
1049 (nvals :scs (any-reg) :target ecx))
1051 (:temporary (:sc unsigned-reg :offset eax-offset :from (:argument 1)) eax)
1052 (:temporary (:sc unsigned-reg :offset esi-offset :from (:argument 2)) esi)
1053 (:temporary (:sc unsigned-reg :offset ecx-offset :from (:argument 3)) ecx)
1054 (:temporary (:sc unsigned-reg :offset ebx-offset :from (:eval 0)) ebx)
1055 (:temporary (:sc descriptor-reg :offset (first *register-arg-offsets*)
1056 :from (:eval 0)) a0)
1057 (:temporary (:sc unsigned-reg :from (:eval 1)) old-fp-temp)
1061 (trace-table-entry trace-table-function-epilogue)
1062 ;; Load the return-pc.
1063 (move eax return-pc)
1064 (unless (policy node (> space speed))
1065 ;; Check for the single case.
1066 (let ((not-single (gen-label)))
1067 (inst cmp nvals (fixnumize 1))
1068 (inst jmp :ne not-single)
1070 ;; Return with one value.
1072 ;; Clear the stack. We load old-fp into a register before clearing
1074 (move old-fp-temp old-fp)
1075 (move esp-tn ebp-tn)
1076 (move ebp-tn old-fp-temp)
1077 ;; Fix the return-pc to point at the single-value entry point.
1082 ;; Nope, not the single case. Jump to the assembly routine.
1083 (emit-label not-single)))
1087 (move ebp-tn old-fp)
1088 (inst jmp (make-fixup 'return-multiple :assembly-routine))
1089 (trace-table-entry trace-table-normal)))
1093 ;;; We don't need to do anything special for regular functions.
1094 (define-vop (setup-environment)
1098 ;; Don't bother doing anything.
1101 ;;; Get the lexical environment from its passing location.
1102 (define-vop (setup-closure-environment)
1103 (:results (closure :scs (descriptor-reg)))
1108 (move closure eax-tn)))
1110 ;;; Copy a &MORE arg from the argument area to the end of the current
1111 ;;; frame. FIXED is the number of non-&MORE arguments.
1113 ;;; The tricky part is doing this without trashing any of the calling
1114 ;;; convention registers that are still needed. This vop is emitted
1115 ;;; directly after the xep-allocate frame. That means the registers
1116 ;;; are in use as follows:
1118 ;;; EAX -- The lexenv.
1119 ;;; EBX -- Available.
1120 ;;; ECX -- The total number of arguments.
1121 ;;; EDX -- The first arg.
1122 ;;; EDI -- The second arg.
1123 ;;; ESI -- The third arg.
1125 ;;; So basically, we have one register available for our use: EBX.
1127 ;;; What we can do is push the other regs onto the stack, and then
1128 ;;; restore their values by looking directly below where we put the
1130 (define-vop (copy-more-arg)
1133 ;; Avoid the copy if there are no more args.
1134 (cond ((zerop fixed)
1135 (inst jecxz just-alloc-frame))
1137 (inst cmp ecx-tn (fixnumize fixed))
1138 (inst jmp :be just-alloc-frame)))
1140 ;; Allocate the space on the stack.
1141 ;; stack = ebp - (max 3 frame-size) - (nargs - fixed)
1143 (make-ea :dword :base ebp-tn
1144 :disp (- (fixnumize fixed)
1146 (max 3 (sb-allocated-size 'stack))))))
1147 (inst sub ebx-tn ecx-tn) ; Got the new stack in ebx
1148 (inst mov esp-tn ebx-tn)
1150 ;; Now: nargs>=1 && nargs>fixed
1152 ;; Save the original count of args.
1153 (inst mov ebx-tn ecx-tn)
1155 (cond ((< fixed register-arg-count)
1156 ;; We must stop when we run out of stack args, not when we
1157 ;; run out of more args.
1158 ;; Number to copy = nargs-3
1159 (inst sub ecx-tn (fixnumize register-arg-count))
1160 ;; Everything of interest in registers.
1161 (inst jmp :be do-regs))
1163 ;; Number to copy = nargs-fixed
1164 (inst sub ecx-tn (fixnumize fixed))))
1166 ;; Save edi and esi register args.
1169 ;; Okay, we have pushed the register args. We can trash them
1172 ;; Initialize dst to be end of stack; skiping the values pushed
1174 (inst lea edi-tn (make-ea :dword :base esp-tn :disp 8))
1176 ;; Initialize src to be end of args.
1177 (inst mov esi-tn ebp-tn)
1178 (inst sub esi-tn ebx-tn)
1180 (inst shr ecx-tn word-shift) ; make word count
1181 ;; And copy the args.
1182 (inst cld) ; auto-inc ESI and EDI.
1186 ;; So now we need to restore EDI and ESI.
1193 (inst mov ecx-tn ebx-tn)
1195 ;; Here: nargs>=1 && nargs>fixed
1196 (when (< fixed register-arg-count)
1197 ;; Now we have to deposit any more args that showed up in
1201 ;; Store it relative to ebp
1202 (inst mov (make-ea :dword :base ebp-tn
1205 (max 3 (sb-allocated-size 'stack))))))
1206 (nth i *register-arg-tns*))
1209 (when (>= i register-arg-count)
1212 ;; Don't deposit any more than there are.
1214 (inst test ecx-tn ecx-tn)
1215 (inst cmp ecx-tn (fixnumize i)))
1216 (inst jmp :eq done)))
1222 (make-ea :dword :base ebp-tn
1223 :disp (- (* n-word-bytes
1224 (max 3 (sb-allocated-size 'stack))))))
1228 ;;; &MORE args are stored contiguously on the stack, starting
1229 ;;; immediately at the context pointer. The context pointer is not
1230 ;;; typed, so the lowtag is 0.
1231 (define-vop (more-arg)
1232 (:translate %more-arg)
1233 (:policy :fast-safe)
1234 (:args (object :scs (descriptor-reg) :to :result)
1235 (index :scs (any-reg) :target temp))
1236 (:arg-types * tagged-num)
1237 (:temporary (:sc unsigned-reg :from (:argument 1) :to :result) temp)
1238 (:results (value :scs (any-reg descriptor-reg)))
1243 (inst mov value (make-ea :dword :base object :index temp))))
1245 (define-vop (more-arg-c)
1246 (:translate %more-arg)
1247 (:policy :fast-safe)
1248 (:args (object :scs (descriptor-reg)))
1250 (:arg-types * (:constant (signed-byte 30)))
1251 (:results (value :scs (any-reg descriptor-reg)))
1255 (make-ea :dword :base object :disp (- (* index n-word-bytes))))))
1258 ;;; Turn more arg (context, count) into a list.
1259 (define-vop (listify-rest-args)
1260 (:translate %listify-rest-args)
1262 (:args (context :scs (descriptor-reg) :target src)
1263 (count :scs (any-reg) :target ecx))
1264 (:arg-types * tagged-num)
1265 (:temporary (:sc unsigned-reg :offset esi-offset :from (:argument 0)) src)
1266 (:temporary (:sc unsigned-reg :offset ecx-offset :from (:argument 1)) ecx)
1267 (:temporary (:sc unsigned-reg :offset eax-offset) eax)
1268 (:temporary (:sc unsigned-reg) dst)
1269 (:results (result :scs (descriptor-reg)))
1272 (let ((enter (gen-label))
1277 ;; Check to see whether there are no args, and just return NIL if so.
1278 (inst mov result nil-value)
1280 (inst lea dst (make-ea :dword :index ecx :scale 2))
1282 (allocation dst dst node)
1283 (inst lea dst (make-ea :byte :base dst :disp list-pointer-lowtag))
1284 ;; Convert the count into a raw value, so that we can use the
1285 ;; LOOP instruction.
1287 ;; Set decrement mode (successive args at lower addresses)
1289 ;; Set up the result.
1291 ;; Jump into the middle of the loop, 'cause that's were we want
1295 ;; Compute a pointer to the next cons.
1296 (inst add dst (* cons-size n-word-bytes))
1297 ;; Store a pointer to this cons in the CDR of the previous cons.
1298 (storew dst dst -1 list-pointer-lowtag)
1300 ;; Grab one value and stash it in the car of this cons.
1302 (storew eax dst 0 list-pointer-lowtag)
1303 ;; Go back for more.
1305 ;; NIL out the last cons.
1306 (storew nil-value dst 1 list-pointer-lowtag))
1307 (emit-label done))))
1309 ;;; Return the location and size of the &MORE arg glob created by
1310 ;;; COPY-MORE-ARG. SUPPLIED is the total number of arguments supplied
1311 ;;; (originally passed in ECX). FIXED is the number of non-rest
1314 ;;; We must duplicate some of the work done by COPY-MORE-ARG, since at
1315 ;;; that time the environment is in a pretty brain-damaged state,
1316 ;;; preventing this info from being returned as values. What we do is
1317 ;;; compute supplied - fixed, and return a pointer that many words
1318 ;;; below the current stack top.
1319 (define-vop (more-arg-context)
1320 (:policy :fast-safe)
1321 (:translate sb!c::%more-arg-context)
1322 (:args (supplied :scs (any-reg) :target count))
1323 (:arg-types positive-fixnum (:constant fixnum))
1325 (:results (context :scs (descriptor-reg))
1326 (count :scs (any-reg)))
1327 (:result-types t tagged-num)
1328 (:note "more-arg-context")
1330 (move count supplied)
1331 ;; SP at this point points at the last arg pushed.
1332 ;; Point to the first more-arg, not above it.
1333 (inst lea context (make-ea :dword :base esp-tn
1334 :index count :scale 1
1335 :disp (- (+ (fixnumize fixed) 4))))
1336 (unless (zerop fixed)
1337 (inst sub count (fixnumize fixed)))))
1339 ;;; Signal wrong argument count error if NARGS isn't equal to COUNT.
1340 (define-vop (verify-argument-count)
1341 (:policy :fast-safe)
1342 (:translate sb!c::%verify-argument-count)
1343 (:args (nargs :scs (any-reg)))
1344 (:arg-types positive-fixnum (:constant t))
1347 (:save-p :compute-only)
1350 (generate-error-code vop invalid-argument-count-error nargs)))
1352 (inst test nargs nargs) ; smaller instruction
1353 (inst cmp nargs (fixnumize count)))
1354 (inst jmp :ne err-lab))))
1356 ;;; Various other error signallers.
1357 (macrolet ((frob (name error translate &rest args)
1358 `(define-vop (,name)
1360 `((:policy :fast-safe)
1361 (:translate ,translate)))
1362 (:args ,@(mapcar (lambda (arg)
1363 `(,arg :scs (any-reg descriptor-reg)))
1366 (:save-p :compute-only)
1368 (error-call vop ,error ,@args)))))
1369 (frob argument-count-error invalid-argument-count-error
1370 sb!c::%argument-count-error nargs)
1371 (frob type-check-error object-not-type-error sb!c::%type-check-error
1373 (frob layout-invalid-error layout-invalid-error sb!c::%layout-invalid-error
1375 (frob odd-key-arguments-error odd-key-arguments-error
1376 sb!c::%odd-key-arguments-error)
1377 (frob unknown-key-argument-error unknown-key-argument-error
1378 sb!c::%unknown-key-argument-error key)
1379 (frob nil-function-returned-error nil-function-returned-error nil fun))