1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
|
/*
+ * QuickThreads -- Threads-building toolkit.
+ * Copyright (c) 1993 by David Keppel
+ *
+ * Permission to use, copy, modify and distribute this software and
+ * its documentation for any purpose and without fee is hereby
+ * granted, provided that the above copyright notice and this notice
+ * appear in all copies. This software is provided as a
+ * proof-of-concept and for demonstration purposes; there is no
+ * representation about the suitability of this software for any
+ * purpose.
+ *
+ * PowerPC-Sys5 thread switching module.
+ *
+ * This software is largely based on the original PowerPC-Linux porting
+ * developed by Ken Aaker <kenaaker@silverbacksystems.com>
+ *
+ * Marco Bucci <marco.bucci@inwind.it>
+ * December 2002
+ *
+ */
#ifndef QUICKTHREADS_POWERPC_H
#define QUICKTHREADS_POWERPC_H
/*****************************************************************************
*
* DESCRIPTION
*
* This is the QuickThreads switching module implementation for PowerPC
* running under System V ABI (Application Binary Interface) [2]. It was
* developed by porting the MacOS X version and tested under LinuxPPC.
*
* Notice that this is not the same than the PowerPC Mach ABI used by MacOSX
* [1].
*
* IMPLEMENTATION NOTES
*
* 1) Porting on System V ABI
* Excluding the variant argument calling convention, Mach and System V ABI
* are enough similar and it could be possible to use some simple macro, to
* adapt the code for both the ABIs. Actually, the only relevant difference
* is in the linkage area structure and in the position where the Link and
* the Condition registers are saved. As to the calling conventions, there
* are differences with floating points argument passing and with variant
* argument lists. Notice that, on Mach, the caller's stack frame allocates
* space to hold all arguments ([1] p.51), while on System V, the caller's
* stack frame allocates space to hold just the arguments that don't fit into
* registers ([2] p.3.18).
*
* 2) Variant argument list implementation
* Variant argument calling on a RISC machine is not easy to implement since
* parameters are passed via registers instead of via stack. In a general
* variant argument implementation, the caller's stack must map the whole
* parameter list following the rules related to the use of the GPR and FPR
* parameter registers and the stack alignment ([2] p.3-21).
* This implementation is quite simple and not general. It works under the
* hypothesis that arguments are 4-bytes aligned integers.
*
* 3) This heather file organisation
* I preferred to not make confusion between macros that are needed (i.e.
* directly used) by QuickThreads and internal "implementation" macros. You
* will find QuickThreds macros in the end of this header. Sometime they just
* refer to an analogous "internal" macro. On the top, there are the macros
* that I used to make more clean (I hope) the implementation. I could include
* some system heather (as to stack layout definitions, prologs and epilogs,
* etc.), but I preferred to have a self-contained heather in order to make
* all more clear for mantaining and for possible porting on another ABI.
*
*
* REFERENCES
*
* [1] - Mach-O Runtime Architecture
* Runtime Concepts and Conventions for Mac OS X Programs
* Preliminary July 2002
*
* [2] - SYSTEM V APPLICATION BINARY INTERFACE
* PowerPC Processor Supplement
* September 1995
*
*****************************************************************************/
/*****************************************************************************
*
* PowerPC System V Stack frame (see [2])
*
................
+ +
| |
+--------------------------+
| | Caller's LR
+ CALLER'S LINKAGE AREA +
backchain -> | | Caller's backchain
+==========================+
| | FPR31
+ FPR SAVE AREA +
..............
+ +
| | FPRn
+--------------------------+
| | GPR31
+ GPR SAVE AREA +
..............
+ +
| | GPRn
+--------------------------+
| |
+ ALIGNMEBNT PAD +
..............
+ (if needed) +
| |
+--------------------------+
| CR SAVE |
+--------------------------+
| |
+ LOCAL VARIABLES AREA +
..............
+ +
| |
+--------------------------+
| | PAR(n-7)
+ +
| |
+ PARAMETER AREA +
..............
+ for FUTURE call +
| | PAR(9)
+ +
SP + 8 -> | | PAR(8)
+--------------------------+
SP + 4 -> | | LR callee-save for FUTURE call
+ LINKAGE AREA +
SP -> | | backchain
+==========================+
STACK TOP (lower address)
Stack grows down
|
V
* NOTE:
*
* 1) In this figure parameter are supposed to be integer 4-bytes aligned and
* are numbered 0, 1, 2,... n.
*
* 2) Parameter are allocated in the CALLER's parameter area. This area must
* be large enough to hold all parameters that cannot fit in registers (no
* more parameter registers are available);
*
* 3) The callee saves LR in the caller's linkage area. CR as all other
* callee's state are saved in its own stack frame.
*
*****************************************************************************/
/*****************************************************************************
*
* Stack initialization for a single argument thread
*
top + QUICKTHREADS_STKBASE -> STACK BOTTOM (higher address)
+==========================+
| |
+ +
..............
+ +
| |
+--------------------------+
top + QUICKTHREADS_ONLY_INDEX * 4 -> | only param | PAR(3)
+ +
top + QUICKTHREADS_USER_INDEX * 4 -> | userf param | PAR(2)
+ +
top + QUICKTHREADS_ARGT_INDEX * 4 -> | t param | PAR(1)
+ +
top + QUICKTHREADS_ARGU_INDEX * 4 -> | u param | PAR(0)
+--------------------------+
top + QUICKTHREADS_RETURN_INDEX * 4 -> | qt_start | LR save
+ +
top + QUICKTHREADS_BLOCKI_FRAME_SIZE -> | top + QUICKTHREADS_STKBASE | backchain
+==========================+
| |
+ +
..............
+ +
| |
+--------------------------+
| |
+ +
top -> |top + QUICKTHREADS_BLOCKI_FRAME_SIZE| backchain
+==========================+
STACK TOP (lower address)
Stack grows down
|
V
*****************************************************************************
*
* Stack initialization for a variant argument thread
*
bottom -> STACK BOTTOM (higher address)
+==========================+
| |
+ +
..............
+ +
top + QUICKTHREADS_VSTKBASE -> | arg(0) | PAR(4)
+--------------------------+
top + QUICKTHREADS_CLEANUP_INDEX * 4 -> | cleanup param | PAR(3)
+ +
top + QUICKTHREADS_USER_INDEX * 4 -> | userf param | PAR(2)
+ +
top + QUICKTHREADS_VSTARTUP_INDEX * 4 ->| startup param | PAR(1)
+ +
top + QUICKTHREADS_ARGT_INDEX * 4 -> | t param | PAR(0)
+--------------------------+
top + QUICKTHREADS_RETURN_INDEX * 4 -> | qt_start | LR save
+ +
top + QUICKTHREADS_BLOCKI_FRAME_SIZE -> | top + QUICKTHREADS_STKBASE | backchain
+==========================+
| |
+ +
..............
+ +
| |
+--------------------------+
| |
+ +
top -> |top + QUICKTHREADS_BLOCKI_FRAME_SIZE| backchain
+==========================+
STACK TOP (lower address)
Stack grows down
|
V
* NOTE:
*
* Parameters are passed to "qt_start" or to "qt_vstart" putting them into
* the stack frames of "qt_start" or "qt_vstart" themselves. This not a
* conventional parameter passing because parameters should be put into the
* caller's stack, not into the callee's one. Actually we must consider
* that as a preload of the parameter area that "qt_start" or "qt_vstart"
* will use for their own calls.
* Be aware of the fact that, during a call, the caller's parameter area is,
* in a certain sense, volatile. In facts, the callee can save parameter
* registers on the caller's parameter area.
*
*****************************************************************************/
/*****************************************************************************
Define PowerPC System V related macros
*****************************************************************************/
typedef unsigned long PPC_W;
/* Stack pointer must always be a multiple of 16 */
#define PPC_STACK_INCR 16
#define PPC_ROUND_STACK(length) \
(((length)+PPC_STACK_INCR-1) & ~(PPC_STACK_INCR-1))
#define PPC_LINKAGE_AREA 8
#define PPC_LR_SAVE 4
#define PPC_PARAM_AREA(n) (4*(n))
#define PPC_GPR_SAVE_AREA (4*19) /* GPR13-GPR31 must be saved */
#define PPC_FPR_SAVE_AREA (8*18) /* FPR14-FPR31 must be saved */
/* Define parameter offset on the stack.
* NOTICE: Parameters are numbered 0, 1, ..., n.
*/
#define PPC_PAR(i) (PPC_LINKAGE_AREA+(i)*4)
/*****************************************************************************
Define stack frames
*****************************************************************************/
/* Define the "qt_blocki" and "qt_abort" stack frame. We use the same stack
* frame for both.
*
top + S ->
+==========================+
top + S - 4 -> | | GPR31
+ GPR SAVE AREA +
..............
+ +
top + S - 19 * 4 -> | | GPR13
+--------------------------+
| |
+ ALIGNMEBNT PAD +
..............
+ (if needed) +
| |
+--------------------------+
top + 8 -> | CR SAVE |
+--------------------------+
| |
+ LINKAGE AREA +
top -> | |
+==========================+
*/
#define QUICKTHREADS_BLOCKI_FRAME_SIZE \
PPC_ROUND_STACK(PPC_LINKAGE_AREA+4+PPC_GPR_SAVE_AREA)
#define QUICKTHREADS_BLOCKI_CR_SAVE 8
/* Offset to the base of the GPR save area. Save from GPR13 to GPR31
* increasing address.
*/
#define QUICKTHREADS_BLOCKI_GPR_SAVE(i) (QUICKTHREADS_BLOCKI_FRAME_SIZE-4+(i-31)*4)
/* Define the "qt_block" stack frame. Notice that since "qt_black" calls
* "qt_blocki", GPR registers are saved into "qt_blocki" stack frame.
*
top + S ->
+==========================+
top + S - 8 -> | | FPR31
+ FPR SAVE AREA +
..............
+ +
top + S - 18 * 8 -> | | FPR14
+--------------------------+
| |
+ ALIGNMEBNT PAD +
..............
+ (if needed) +
| |
+--------------------------+
| |
+ LINKAGE AREA +
top -> | |
+==========================+
*/
#define QUICKTHREADS_BLOCK_FRAME_SIZE \
PPC_ROUND_STACK(PPC_LINKAGE_AREA+PPC_FPR_SAVE_AREA)
/* Offset to the location where registers are saved.
*/
#define QUICKTHREADS_BLOCK_FPR_SAVE(i) (QUICKTHREADS_BLOCK_FRAME_SIZE-8+(i-31)*8)
/* Define the "qt_start" frame size. It consists just of the linkage area and
* the parameter area.
*
+==========================+
| |
+ ALIGNMEBNT PAD +
..............
+ (if needed) +
| |
+--------------------------+
| | only par
+ +
| | userf par
+ PARAMETER AREA +
| | t par
+ +
top + 8 -> | | u par
+--------------------------+
| |
+ LINKAGE AREA +
top -> | |
+==========================+
*/
#define QUICKTHREADS_START_FRAME_SIZE PPC_ROUND_STACK(PPC_LINKAGE_AREA+PPC_PARAM_AREA(4))
/* Define the "qt_vstart" frame. It consists of the linkage area, the fix parameter
* area, the variant argument list and a local variable area used in "qt_vstart"
* implementation.
*
backchain ->
+==========================+
backchain - 4 -> | |
+ LOCAL VARIABLES AREA +
..............
+ +
| |
+--------------------------+
| |
+ ALIGNMEBNT PAD +
..............
+ (if needed) +
| |
+--------------------------+
| | arg(n)
+ +
| |
+ VARIABLE ARGUMENT LIST +
..............
+ for userf call +
| | arg(1)
+ +
top + 8 + 16 -> | | arg(0)
+--------------------------+
| | cleanup par
+ +
| | userf par
+ PARAMETER AREA +
| | startup par
+ +
top + 8 -> | | t par
+--------------------------+
| |
+ LINKAGE AREA +
top -> | |
+==========================+
*/
#define QUICKTHREADS_VARGS_LOCAL_AREA (4*4) /* local variable area */
/* The offset the stack will be moved back before to call "userf(...)".
* The linckage area must be moved to be adiacent to the part of the variant
* argument list that is in the stack. Notice that, since the first 8
* parameters are passed via registers, the offset is equal to the size of
* 4+8 parameters. */
#define QUICKTHREADS_VARGS_BKOFF PPC_PARAM_AREA(4+8)
#define QUICKTHREADS_VSTART_FRAME_SIZE(varbytes) \
PPC_ROUND_STACK(PPC_LINKAGE_AREA+QUICKTHREADS_VARGS_BKOFF+(varbytes)+ \
QUICKTHREADS_VARGS_LOCAL_AREA)
/* Offset to the base of the varian argument list */
#define QUICKTHREADS_VSTART_LIST_BASE (PPC_LINKAGE_AREA+PPC_PARAM_AREA(4))
/* Notice that qt_start and qt_vstart have no parameters, actually their
* parameters are written in their stack frame during thread initialization
*/
extern void qt_start(void);
extern void qt_vstart(void);
/* Offset (in words) of the location where the block routine saves its return
* address (i.e. LR). SP points the top of the block routine stack and,
* following ppc calling conventions, the return address is saved in the
* previous (caller's) stack frame.
*/
#define QUICKTHREADS_RETURN_INDEX ((QUICKTHREADS_BLOCKI_FRAME_SIZE+PPC_LR_SAVE)/sizeof(PPC_W))
/* static variable used to get the stack bottom in "VARGS" initialization */
static void *qt_sp_bottom_save;
#define QUICKTHREADS_ARG_INDEX(i) ((QUICKTHREADS_BLOCKI_FRAME_SIZE+PPC_PAR(i))/sizeof(PPC_W))
/*****************************************************************************
QuickThreads needed definitions
*****************************************************************************/
#define QUICKTHREADS_GROW_DOWN
#define QUICKTHREADS_STKALIGN PPC_STACK_INCR
typedef PPC_W qt_word_t;
/* This macro is used by "QUICKTHREADS_ARGS" to initialize a single argument thread.
* - set "qt_start" as the "qt_block" or "qt_blocki" return address;
* - set the top of the stack backchain;
* - set the next backchain (not needed, but just to be "clean").
*/
#define QUICKTHREADS_ARGS_MD(sp) \
(QUICKTHREADS_SPUT (sp, QUICKTHREADS_RETURN_INDEX, qt_start), \
QUICKTHREADS_SPUT (sp, 0, sp+QUICKTHREADS_BLOCKI_FRAME_SIZE), \
QUICKTHREADS_SPUT (sp, QUICKTHREADS_BLOCKI_FRAME_SIZE/sizeof(PPC_W), \
sp+QUICKTHREADS_BLOCKI_FRAME_SIZE+QUICKTHREADS_START_FRAME_SIZE))
/* This macro is used by "QUICKTHREADS_VARGS" to initialize a variant argument thread.
* It returns the pointer to the top of the argument list.
* We also use it to get the stack bottom via a static variable. This is a bit
* "dirty", it could be better to do it in "qt_vargs", but we don't want change
* anything out of this file.
* We need the stack bottom to allocate a local variable area used by
* "qt_vstart".
*/
#define QUICKTHREADS_VARGS_MD0(sp, varbytes) \
((qt_sp_bottom_save = sp), \
((qt_t *)(((char *)(sp)) - \
(QUICKTHREADS_VSTART_FRAME_SIZE(varbytes)-QUICKTHREADS_VSTART_LIST_BASE))))
/* This macro is used by "QUICKTHREADS_VARGS" to initialize a variant argument thread.
* - set "qt_start" as the "qt_block" or "qt_blocki" return address;
* - set the top of the stackback chain;
* - set the next backchain (it points the stack botton).
*/
#define QUICKTHREADS_VARGS_MD1(sp) \
(QUICKTHREADS_SPUT (sp, QUICKTHREADS_RETURN_INDEX, qt_vstart), \
QUICKTHREADS_SPUT (sp, 0, sp+QUICKTHREADS_BLOCKI_FRAME_SIZE), \
QUICKTHREADS_SPUT (sp, (QUICKTHREADS_BLOCKI_FRAME_SIZE)/sizeof(PPC_W), \
qt_sp_bottom_save))
/* Activate "qt_vargs" as the initialization routine for the variant
* argument threads
*/
#define QUICKTHREADS_VARGS_DEFAULT
/* Override "qt_vargs" with "qt_vargs_stdarg".
* On LinuxPPC "qt_vargs" doesn't work, "qt_vargs_stdarg" uses a more
* standard way to retrieve arguments from the variant list.
*/
#define QUICKTHREADS_VARGS(sp, nbytes, vargs, pt, startup, vuserf, cleanup) \
((qt_t *)qt_vargs_stdarg (sp, nbytes, vargs, pt, startup, vuserf, cleanup))
/* This macro is used by "QUICKTHREADS_ADJ(sp)" to get the stack top form the stack
* bottom during a single argument thread initialization.
* It is the space we need to allocate for a single argument thread: the stack
* frame for the block routine ("qt_block" or "qt_blocki") and for "qt_start".
*/
#define QUICKTHREADS_STKBASE \
(QUICKTHREADS_BLOCKI_FRAME_SIZE+QUICKTHREADS_START_FRAME_SIZE)
/* This macro is used by "QUICKTHREADS_VADJ(sp)" to get the stack top from the base
* of the variant argument list during a variant argument thread initialization.
*/
#define QUICKTHREADS_VSTKBASE (QUICKTHREADS_BLOCKI_FRAME_SIZE+QUICKTHREADS_VSTART_LIST_BASE)
/* The *index* (positive offset) of where to put each value. */
#define QUICKTHREADS_ARGU_INDEX QUICKTHREADS_ARG_INDEX(0)
#define QUICKTHREADS_ARGT_INDEX QUICKTHREADS_ARG_INDEX(1)
#define QUICKTHREADS_USER_INDEX QUICKTHREADS_ARG_INDEX(2)
#define QUICKTHREADS_ONLY_INDEX QUICKTHREADS_ARG_INDEX(3)
#define QUICKTHREADS_VARGT_INDEX QUICKTHREADS_ARG_INDEX(0)
#define QUICKTHREADS_VSTARTUP_INDEX QUICKTHREADS_ARG_INDEX(1)
#define QUICKTHREADS_VUSERF_INDEX QUICKTHREADS_ARG_INDEX(2)
#define QUICKTHREADS_VCLEANUP_INDEX QUICKTHREADS_ARG_INDEX(3)
#endif /* ndef QUICKTHREADS_POWERPC_H */
|
