| blob | c3f8d3c9a2f29a073fc5148d23f62bfaea059597 |
1 ;;;; the machine specific support routines needed by the file assembler
3 ;;;; This software is part of the SBCL system. See the README file for
4 ;;;; more information.
5 ;;;;
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.
13 \f
14 ;;;; RETURN-MULTIPLE
16 ;;; For RETURN-MULTIPLE, we have to move the results from the end of
17 ;;; the frame for the function that is returning to the end of the
18 ;;; frame for the function being returned to.
29 ;; These we need as temporaries.
33 ;; Pick off the cases where everything fits in register args.
42 ;; Save the count, because the loop is going to destroy it.
45 ;; Blit the values down the stack. Note: there might be overlap, so
46 ;; we have to be careful not to clobber values before we've read
47 ;; them. Because the stack builds down, we are coping to a larger
48 ;; address. Therefore, we need to iterate from larger addresses to
49 ;; smaller addresses. pfw-this says copy ecx words from esi to edi
50 ;; counting down.
58 ;; Restore the count.
61 ;; Set the stack top to the last result.
64 ;; Load the register args.
69 ;; And back we go.
73 ;; Handle the register arg cases.
74 ZERO-VALUES
82 ONE-VALUE ; Note: we can get this, because the return-multiple vop
83 ; doesn't check for this case when size > speed.
89 TWO-VALUES
97 THREE-VALUES
104 \f
105 ;;;; TAIL-CALL-VARIABLE
107 ;;; For tail-call-variable, we have to copy the arguments from the end
108 ;;; of our stack frame (were args are produced) to the start of our
109 ;;; stack frame (were args are expected).
110 ;;;
111 ;;; We take the function to call in EAX and a pointer to the arguments in
112 ;;; ESI. EBP says the same over the jump, and the old frame pointer is
113 ;;; still saved in the first stack slot. The return-pc is saved in
114 ;;; the second stack slot, so we have to push it to make it look like
115 ;;; we actually called. We also have to compute ECX from the difference
116 ;;; between ESI and the stack top.
129 ;; Calculate NARGS (as a fixnum)
133 ;; Check for all the args fitting the registers.
137 ;; Save the OLD-FP and RETURN-PC because the blit it going to trash
138 ;; those stack locations. Save the ECX, because the loop is going
139 ;; to trash it.
144 ;; Do the blit. Because we are coping from smaller addresses to
145 ;; larger addresses, we have to start at the largest pair and work
146 ;; our way down.
154 ;; Load the register arguments carefully.
157 ;; Restore OLD-FP and ECX.
161 ;; Blow off the stack above the arguments.
164 ;; remaining register args
168 ;; Push the (saved) return-pc so it looks like we just called.
171 ;; And jump into the function.
175 fun-pointer-lowtag)))
177 ;; All the arguments fit in registers, so load them.
178 REGISTER-ARGS
183 ;; Clear most of the stack.
187 ;; Push the return-pc so it looks like we just called.
190 ;; And away we go.
193 fun-pointer-lowtag))))
194 \f
206 LOOP
218 EXIT
220 ;; Here EAX points to catch block containing symbol pointed to by EDX.
223 ;;;; non-local exit noise
241 ;; Does *CURRENT-UNWIND-PROTECT-BLOCK* match the value stored in
242 ;; argument's CURRENT-UWP-SLOT?
245 ;; If a match, return to context in arg block.
248 ;; Not a match - return to *CURRENT-UNWIND-PROTECT-BLOCK* context.
249 ;; Important! Must save (and return) the arg 'block' for later use!!
252 ;; Set next unwind protect context.
254 ;; we're about to reload ebp anyway, so let's borrow it here as a
255 ;; temporary. Hope this works
258 DO-EXIT
262 ;; Uwp-entry expects some things in known locations so that they can
263 ;; be saved on the stack: the block in edx-tn, start in ebx-tn, and
264 ;; count in ecx-tn.