/
asm_386.s
1683 lines (1489 loc) · 43.1 KB
/
asm_386.s
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
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
#include "go_asm.h"
#include "go_tls.h"
#include "funcdata.h"
#include "textflag.h"
// _rt0_386 is common startup code for most 386 systems when using
// internal linking. This is the entry point for the program from the
// kernel for an ordinary -buildmode=exe program. The stack holds the
// number of arguments and the C-style argv.
TEXT _rt0_386(SB),NOSPLIT,$8
MOVL 8(SP), AX // argc
LEAL 12(SP), BX // argv
MOVL AX, 0(SP)
MOVL BX, 4(SP)
JMP runtime·rt0_go(SB)
// _rt0_386_lib is common startup code for most 386 systems when
// using -buildmode=c-archive or -buildmode=c-shared. The linker will
// arrange to invoke this function as a global constructor (for
// c-archive) or when the shared library is loaded (for c-shared).
// We expect argc and argv to be passed on the stack following the
// usual C ABI.
TEXT _rt0_386_lib(SB),NOSPLIT,$0
PUSHL BP
MOVL SP, BP
PUSHL BX
PUSHL SI
PUSHL DI
MOVL 8(BP), AX
MOVL AX, _rt0_386_lib_argc<>(SB)
MOVL 12(BP), AX
MOVL AX, _rt0_386_lib_argv<>(SB)
// Synchronous initialization.
CALL runtime·libpreinit(SB)
SUBL $8, SP
// Create a new thread to do the runtime initialization.
MOVL _cgo_sys_thread_create(SB), AX
TESTL AX, AX
JZ nocgo
// Align stack to call C function.
// We moved SP to BP above, but BP was clobbered by the libpreinit call.
MOVL SP, BP
ANDL $~15, SP
MOVL $_rt0_386_lib_go(SB), BX
MOVL BX, 0(SP)
MOVL $0, 4(SP)
CALL AX
MOVL BP, SP
JMP restore
nocgo:
MOVL $0x800000, 0(SP) // stacksize = 8192KB
MOVL $_rt0_386_lib_go(SB), AX
MOVL AX, 4(SP) // fn
CALL runtime·newosproc0(SB)
restore:
ADDL $8, SP
POPL DI
POPL SI
POPL BX
POPL BP
RET
// _rt0_386_lib_go initializes the Go runtime.
// This is started in a separate thread by _rt0_386_lib.
TEXT _rt0_386_lib_go(SB),NOSPLIT,$8
MOVL _rt0_386_lib_argc<>(SB), AX
MOVL AX, 0(SP)
MOVL _rt0_386_lib_argv<>(SB), AX
MOVL AX, 4(SP)
JMP runtime·rt0_go(SB)
DATA _rt0_386_lib_argc<>(SB)/4, $0
GLOBL _rt0_386_lib_argc<>(SB),NOPTR, $4
DATA _rt0_386_lib_argv<>(SB)/4, $0
GLOBL _rt0_386_lib_argv<>(SB),NOPTR, $4
TEXT runtime·rt0_go(SB),NOSPLIT|NOFRAME|TOPFRAME,$0
// Copy arguments forward on an even stack.
// Users of this function jump to it, they don't call it.
MOVL 0(SP), AX
MOVL 4(SP), BX
SUBL $128, SP // plenty of scratch
ANDL $~15, SP
MOVL AX, 120(SP) // save argc, argv away
MOVL BX, 124(SP)
// set default stack bounds.
// _cgo_init may update stackguard.
MOVL $runtime·g0(SB), BP
LEAL (-64*1024+104)(SP), BX
MOVL BX, g_stackguard0(BP)
MOVL BX, g_stackguard1(BP)
MOVL BX, (g_stack+stack_lo)(BP)
MOVL SP, (g_stack+stack_hi)(BP)
// find out information about the processor we're on
// first see if CPUID instruction is supported.
PUSHFL
PUSHFL
XORL $(1<<21), 0(SP) // flip ID bit
POPFL
PUSHFL
POPL AX
XORL 0(SP), AX
POPFL // restore EFLAGS
TESTL $(1<<21), AX
JNE has_cpuid
bad_proc: // show that the program requires MMX.
MOVL $2, 0(SP)
MOVL $bad_proc_msg<>(SB), 4(SP)
MOVL $0x3d, 8(SP)
CALL runtime·write(SB)
MOVL $1, 0(SP)
CALL runtime·exit(SB)
CALL runtime·abort(SB)
has_cpuid:
MOVL $0, AX
CPUID
MOVL AX, SI
CMPL AX, $0
JE nocpuinfo
CMPL BX, $0x756E6547 // "Genu"
JNE notintel
CMPL DX, $0x49656E69 // "ineI"
JNE notintel
CMPL CX, $0x6C65746E // "ntel"
JNE notintel
MOVB $1, runtime·isIntel(SB)
notintel:
// Load EAX=1 cpuid flags
MOVL $1, AX
CPUID
MOVL CX, DI // Move to global variable clobbers CX when generating PIC
MOVL AX, runtime·processorVersionInfo(SB)
// Check for MMX support
TESTL $(1<<23), DX // MMX
JZ bad_proc
nocpuinfo:
// if there is an _cgo_init, call it to let it
// initialize and to set up GS. if not,
// we set up GS ourselves.
MOVL _cgo_init(SB), AX
TESTL AX, AX
JZ needtls
#ifdef GOOS_android
// arg 4: TLS base, stored in slot 0 (Android's TLS_SLOT_SELF).
// Compensate for tls_g (+8).
MOVL -8(TLS), BX
MOVL BX, 12(SP)
MOVL $runtime·tls_g(SB), 8(SP) // arg 3: &tls_g
#else
MOVL $0, BX
MOVL BX, 12(SP) // arg 4: not used when using platform's TLS
#ifdef GOOS_windows
MOVL $runtime·tls_g(SB), 8(SP) // arg 3: &tls_g
#else
MOVL BX, 8(SP) // arg 3: not used when using platform's TLS
#endif
#endif
MOVL $setg_gcc<>(SB), BX
MOVL BX, 4(SP) // arg 2: setg_gcc
MOVL BP, 0(SP) // arg 1: g0
CALL AX
// update stackguard after _cgo_init
MOVL $runtime·g0(SB), CX
MOVL (g_stack+stack_lo)(CX), AX
ADDL $const_stackGuard, AX
MOVL AX, g_stackguard0(CX)
MOVL AX, g_stackguard1(CX)
#ifndef GOOS_windows
// skip runtime·ldt0setup(SB) and tls test after _cgo_init for non-windows
JMP ok
#endif
needtls:
#ifdef GOOS_openbsd
// skip runtime·ldt0setup(SB) and tls test on OpenBSD in all cases
JMP ok
#endif
#ifdef GOOS_plan9
// skip runtime·ldt0setup(SB) and tls test on Plan 9 in all cases
JMP ok
#endif
// set up %gs
CALL ldt0setup<>(SB)
// store through it, to make sure it works
get_tls(BX)
MOVL $0x123, g(BX)
MOVL runtime·m0+m_tls(SB), AX
CMPL AX, $0x123
JEQ ok
MOVL AX, 0 // abort
ok:
// set up m and g "registers"
get_tls(BX)
LEAL runtime·g0(SB), DX
MOVL DX, g(BX)
LEAL runtime·m0(SB), AX
// save m->g0 = g0
MOVL DX, m_g0(AX)
// save g0->m = m0
MOVL AX, g_m(DX)
CALL runtime·emptyfunc(SB) // fault if stack check is wrong
// convention is D is always cleared
CLD
CALL runtime·check(SB)
// saved argc, argv
MOVL 120(SP), AX
MOVL AX, 0(SP)
MOVL 124(SP), AX
MOVL AX, 4(SP)
CALL runtime·args(SB)
CALL runtime·osinit(SB)
CALL runtime·schedinit(SB)
// create a new goroutine to start program
PUSHL $runtime·mainPC(SB) // entry
CALL runtime·newproc(SB)
POPL AX
// start this M
CALL runtime·mstart(SB)
CALL runtime·abort(SB)
RET
DATA bad_proc_msg<>+0x00(SB)/61, $"This program can only be run on processors with MMX support.\n"
GLOBL bad_proc_msg<>(SB), RODATA, $61
DATA runtime·mainPC+0(SB)/4,$runtime·main(SB)
GLOBL runtime·mainPC(SB),RODATA,$4
TEXT runtime·breakpoint(SB),NOSPLIT,$0-0
INT $3
RET
TEXT runtime·asminit(SB),NOSPLIT,$0-0
// Linux and MinGW start the FPU in extended double precision.
// Other operating systems use double precision.
// Change to double precision to match them,
// and to match other hardware that only has double.
FLDCW runtime·controlWord64(SB)
RET
TEXT runtime·mstart(SB),NOSPLIT|TOPFRAME,$0
CALL runtime·mstart0(SB)
RET // not reached
/*
* go-routine
*/
// void gogo(Gobuf*)
// restore state from Gobuf; longjmp
TEXT runtime·gogo(SB), NOSPLIT, $0-4
MOVL buf+0(FP), BX // gobuf
MOVL gobuf_g(BX), DX
MOVL 0(DX), CX // make sure g != nil
JMP gogo<>(SB)
TEXT gogo<>(SB), NOSPLIT, $0
get_tls(CX)
MOVL DX, g(CX)
MOVL gobuf_sp(BX), SP // restore SP
MOVL gobuf_ret(BX), AX
MOVL gobuf_ctxt(BX), DX
MOVL $0, gobuf_sp(BX) // clear to help garbage collector
MOVL $0, gobuf_ret(BX)
MOVL $0, gobuf_ctxt(BX)
MOVL gobuf_pc(BX), BX
JMP BX
// func mcall(fn func(*g))
// Switch to m->g0's stack, call fn(g).
// Fn must never return. It should gogo(&g->sched)
// to keep running g.
TEXT runtime·mcall(SB), NOSPLIT, $0-4
MOVL fn+0(FP), DI
get_tls(DX)
MOVL g(DX), AX // save state in g->sched
MOVL 0(SP), BX // caller's PC
MOVL BX, (g_sched+gobuf_pc)(AX)
LEAL fn+0(FP), BX // caller's SP
MOVL BX, (g_sched+gobuf_sp)(AX)
// switch to m->g0 & its stack, call fn
MOVL g(DX), BX
MOVL g_m(BX), BX
MOVL m_g0(BX), SI
CMPL SI, AX // if g == m->g0 call badmcall
JNE 3(PC)
MOVL $runtime·badmcall(SB), AX
JMP AX
MOVL SI, g(DX) // g = m->g0
MOVL (g_sched+gobuf_sp)(SI), SP // sp = m->g0->sched.sp
PUSHL AX
MOVL DI, DX
MOVL 0(DI), DI
CALL DI
POPL AX
MOVL $runtime·badmcall2(SB), AX
JMP AX
RET
// systemstack_switch is a dummy routine that systemstack leaves at the bottom
// of the G stack. We need to distinguish the routine that
// lives at the bottom of the G stack from the one that lives
// at the top of the system stack because the one at the top of
// the system stack terminates the stack walk (see topofstack()).
TEXT runtime·systemstack_switch(SB), NOSPLIT, $0-0
RET
// func systemstack(fn func())
TEXT runtime·systemstack(SB), NOSPLIT, $0-4
MOVL fn+0(FP), DI // DI = fn
get_tls(CX)
MOVL g(CX), AX // AX = g
MOVL g_m(AX), BX // BX = m
CMPL AX, m_gsignal(BX)
JEQ noswitch
MOVL m_g0(BX), DX // DX = g0
CMPL AX, DX
JEQ noswitch
CMPL AX, m_curg(BX)
JNE bad
// switch stacks
// save our state in g->sched. Pretend to
// be systemstack_switch if the G stack is scanned.
CALL gosave_systemstack_switch<>(SB)
// switch to g0
get_tls(CX)
MOVL DX, g(CX)
MOVL (g_sched+gobuf_sp)(DX), BX
MOVL BX, SP
// call target function
MOVL DI, DX
MOVL 0(DI), DI
CALL DI
// switch back to g
get_tls(CX)
MOVL g(CX), AX
MOVL g_m(AX), BX
MOVL m_curg(BX), AX
MOVL AX, g(CX)
MOVL (g_sched+gobuf_sp)(AX), SP
MOVL $0, (g_sched+gobuf_sp)(AX)
RET
noswitch:
// already on system stack; tail call the function
// Using a tail call here cleans up tracebacks since we won't stop
// at an intermediate systemstack.
MOVL DI, DX
MOVL 0(DI), DI
JMP DI
bad:
// Bad: g is not gsignal, not g0, not curg. What is it?
// Hide call from linker nosplit analysis.
MOVL $runtime·badsystemstack(SB), AX
CALL AX
INT $3
// func switchToCrashStack0(fn func())
TEXT runtime·switchToCrashStack0(SB), NOSPLIT, $0-4
MOVL fn+0(FP), AX
get_tls(CX)
MOVL g(CX), BX // BX = g
MOVL g_m(BX), DX // DX = curm
// set g to gcrash
LEAL runtime·gcrash(SB), BX // g = &gcrash
MOVL DX, g_m(BX) // g.m = curm
MOVL BX, m_g0(DX) // curm.g0 = g
get_tls(CX)
MOVL BX, g(CX)
// switch to crashstack
MOVL (g_stack+stack_hi)(BX), DX
SUBL $(4*8), DX
MOVL DX, SP
// call target function
MOVL AX, DX
MOVL 0(AX), AX
CALL AX
// should never return
CALL runtime·abort(SB)
UNDEF
/*
* support for morestack
*/
// Called during function prolog when more stack is needed.
//
// The traceback routines see morestack on a g0 as being
// the top of a stack (for example, morestack calling newstack
// calling the scheduler calling newm calling gc), so we must
// record an argument size. For that purpose, it has no arguments.
TEXT runtime·morestack(SB),NOSPLIT|NOFRAME,$0-0
// Cannot grow scheduler stack (m->g0).
get_tls(CX)
MOVL g(CX), DI
MOVL g_m(DI), BX
// Set g->sched to context in f.
MOVL 0(SP), AX // f's PC
MOVL AX, (g_sched+gobuf_pc)(DI)
LEAL 4(SP), AX // f's SP
MOVL AX, (g_sched+gobuf_sp)(DI)
MOVL DX, (g_sched+gobuf_ctxt)(DI)
MOVL m_g0(BX), SI
CMPL g(CX), SI
JNE 3(PC)
CALL runtime·badmorestackg0(SB)
CALL runtime·abort(SB)
// Cannot grow signal stack.
MOVL m_gsignal(BX), SI
CMPL g(CX), SI
JNE 3(PC)
CALL runtime·badmorestackgsignal(SB)
CALL runtime·abort(SB)
// Called from f.
// Set m->morebuf to f's caller.
NOP SP // tell vet SP changed - stop checking offsets
MOVL 4(SP), DI // f's caller's PC
MOVL DI, (m_morebuf+gobuf_pc)(BX)
LEAL 8(SP), CX // f's caller's SP
MOVL CX, (m_morebuf+gobuf_sp)(BX)
get_tls(CX)
MOVL g(CX), SI
MOVL SI, (m_morebuf+gobuf_g)(BX)
// Call newstack on m->g0's stack.
MOVL m_g0(BX), BP
MOVL BP, g(CX)
MOVL (g_sched+gobuf_sp)(BP), AX
MOVL -4(AX), BX // fault if CALL would, before smashing SP
MOVL AX, SP
CALL runtime·newstack(SB)
CALL runtime·abort(SB) // crash if newstack returns
RET
TEXT runtime·morestack_noctxt(SB),NOSPLIT,$0-0
MOVL $0, DX
JMP runtime·morestack(SB)
// reflectcall: call a function with the given argument list
// func call(stackArgsType *_type, f *FuncVal, stackArgs *byte, stackArgsSize, stackRetOffset, frameSize uint32, regArgs *abi.RegArgs).
// we don't have variable-sized frames, so we use a small number
// of constant-sized-frame functions to encode a few bits of size in the pc.
// Caution: ugly multiline assembly macros in your future!
#define DISPATCH(NAME,MAXSIZE) \
CMPL CX, $MAXSIZE; \
JA 3(PC); \
MOVL $NAME(SB), AX; \
JMP AX
// Note: can't just "JMP NAME(SB)" - bad inlining results.
TEXT ·reflectcall(SB), NOSPLIT, $0-28
MOVL frameSize+20(FP), CX
DISPATCH(runtime·call16, 16)
DISPATCH(runtime·call32, 32)
DISPATCH(runtime·call64, 64)
DISPATCH(runtime·call128, 128)
DISPATCH(runtime·call256, 256)
DISPATCH(runtime·call512, 512)
DISPATCH(runtime·call1024, 1024)
DISPATCH(runtime·call2048, 2048)
DISPATCH(runtime·call4096, 4096)
DISPATCH(runtime·call8192, 8192)
DISPATCH(runtime·call16384, 16384)
DISPATCH(runtime·call32768, 32768)
DISPATCH(runtime·call65536, 65536)
DISPATCH(runtime·call131072, 131072)
DISPATCH(runtime·call262144, 262144)
DISPATCH(runtime·call524288, 524288)
DISPATCH(runtime·call1048576, 1048576)
DISPATCH(runtime·call2097152, 2097152)
DISPATCH(runtime·call4194304, 4194304)
DISPATCH(runtime·call8388608, 8388608)
DISPATCH(runtime·call16777216, 16777216)
DISPATCH(runtime·call33554432, 33554432)
DISPATCH(runtime·call67108864, 67108864)
DISPATCH(runtime·call134217728, 134217728)
DISPATCH(runtime·call268435456, 268435456)
DISPATCH(runtime·call536870912, 536870912)
DISPATCH(runtime·call1073741824, 1073741824)
MOVL $runtime·badreflectcall(SB), AX
JMP AX
#define CALLFN(NAME,MAXSIZE) \
TEXT NAME(SB), WRAPPER, $MAXSIZE-28; \
NO_LOCAL_POINTERS; \
/* copy arguments to stack */ \
MOVL stackArgs+8(FP), SI; \
MOVL stackArgsSize+12(FP), CX; \
MOVL SP, DI; \
REP;MOVSB; \
/* call function */ \
MOVL f+4(FP), DX; \
MOVL (DX), AX; \
PCDATA $PCDATA_StackMapIndex, $0; \
CALL AX; \
/* copy return values back */ \
MOVL stackArgsType+0(FP), DX; \
MOVL stackArgs+8(FP), DI; \
MOVL stackArgsSize+12(FP), CX; \
MOVL stackRetOffset+16(FP), BX; \
MOVL SP, SI; \
ADDL BX, DI; \
ADDL BX, SI; \
SUBL BX, CX; \
CALL callRet<>(SB); \
RET
// callRet copies return values back at the end of call*. This is a
// separate function so it can allocate stack space for the arguments
// to reflectcallmove. It does not follow the Go ABI; it expects its
// arguments in registers.
TEXT callRet<>(SB), NOSPLIT, $20-0
MOVL DX, 0(SP)
MOVL DI, 4(SP)
MOVL SI, 8(SP)
MOVL CX, 12(SP)
MOVL $0, 16(SP)
CALL runtime·reflectcallmove(SB)
RET
CALLFN(·call16, 16)
CALLFN(·call32, 32)
CALLFN(·call64, 64)
CALLFN(·call128, 128)
CALLFN(·call256, 256)
CALLFN(·call512, 512)
CALLFN(·call1024, 1024)
CALLFN(·call2048, 2048)
CALLFN(·call4096, 4096)
CALLFN(·call8192, 8192)
CALLFN(·call16384, 16384)
CALLFN(·call32768, 32768)
CALLFN(·call65536, 65536)
CALLFN(·call131072, 131072)
CALLFN(·call262144, 262144)
CALLFN(·call524288, 524288)
CALLFN(·call1048576, 1048576)
CALLFN(·call2097152, 2097152)
CALLFN(·call4194304, 4194304)
CALLFN(·call8388608, 8388608)
CALLFN(·call16777216, 16777216)
CALLFN(·call33554432, 33554432)
CALLFN(·call67108864, 67108864)
CALLFN(·call134217728, 134217728)
CALLFN(·call268435456, 268435456)
CALLFN(·call536870912, 536870912)
CALLFN(·call1073741824, 1073741824)
TEXT runtime·procyield(SB),NOSPLIT,$0-0
MOVL cycles+0(FP), AX
again:
PAUSE
SUBL $1, AX
JNZ again
RET
TEXT ·publicationBarrier(SB),NOSPLIT,$0-0
// Stores are already ordered on x86, so this is just a
// compile barrier.
RET
// Save state of caller into g->sched,
// but using fake PC from systemstack_switch.
// Must only be called from functions with no locals ($0)
// or else unwinding from systemstack_switch is incorrect.
TEXT gosave_systemstack_switch<>(SB),NOSPLIT,$0
PUSHL AX
PUSHL BX
get_tls(BX)
MOVL g(BX), BX
LEAL arg+0(FP), AX
MOVL AX, (g_sched+gobuf_sp)(BX)
MOVL $runtime·systemstack_switch(SB), AX
MOVL AX, (g_sched+gobuf_pc)(BX)
MOVL $0, (g_sched+gobuf_ret)(BX)
// Assert ctxt is zero. See func save.
MOVL (g_sched+gobuf_ctxt)(BX), AX
TESTL AX, AX
JZ 2(PC)
CALL runtime·abort(SB)
POPL BX
POPL AX
RET
// func asmcgocall_no_g(fn, arg unsafe.Pointer)
// Call fn(arg) aligned appropriately for the gcc ABI.
// Called on a system stack, and there may be no g yet (during needm).
TEXT ·asmcgocall_no_g(SB),NOSPLIT,$0-8
MOVL fn+0(FP), AX
MOVL arg+4(FP), BX
MOVL SP, DX
SUBL $32, SP
ANDL $~15, SP // alignment, perhaps unnecessary
MOVL DX, 8(SP) // save old SP
MOVL BX, 0(SP) // first argument in x86-32 ABI
CALL AX
MOVL 8(SP), DX
MOVL DX, SP
RET
// func asmcgocall(fn, arg unsafe.Pointer) int32
// Call fn(arg) on the scheduler stack,
// aligned appropriately for the gcc ABI.
// See cgocall.go for more details.
TEXT ·asmcgocall(SB),NOSPLIT,$0-12
MOVL fn+0(FP), AX
MOVL arg+4(FP), BX
MOVL SP, DX
// Figure out if we need to switch to m->g0 stack.
// We get called to create new OS threads too, and those
// come in on the m->g0 stack already. Or we might already
// be on the m->gsignal stack.
get_tls(CX)
MOVL g(CX), DI
CMPL DI, $0
JEQ nosave // Don't even have a G yet.
MOVL g_m(DI), BP
CMPL DI, m_gsignal(BP)
JEQ noswitch
MOVL m_g0(BP), SI
CMPL DI, SI
JEQ noswitch
CALL gosave_systemstack_switch<>(SB)
get_tls(CX)
MOVL SI, g(CX)
MOVL (g_sched+gobuf_sp)(SI), SP
noswitch:
// Now on a scheduling stack (a pthread-created stack).
SUBL $32, SP
ANDL $~15, SP // alignment, perhaps unnecessary
MOVL DI, 8(SP) // save g
MOVL (g_stack+stack_hi)(DI), DI
SUBL DX, DI
MOVL DI, 4(SP) // save depth in stack (can't just save SP, as stack might be copied during a callback)
MOVL BX, 0(SP) // first argument in x86-32 ABI
CALL AX
// Restore registers, g, stack pointer.
get_tls(CX)
MOVL 8(SP), DI
MOVL (g_stack+stack_hi)(DI), SI
SUBL 4(SP), SI
MOVL DI, g(CX)
MOVL SI, SP
MOVL AX, ret+8(FP)
RET
nosave:
// Now on a scheduling stack (a pthread-created stack).
SUBL $32, SP
ANDL $~15, SP // alignment, perhaps unnecessary
MOVL DX, 4(SP) // save original stack pointer
MOVL BX, 0(SP) // first argument in x86-32 ABI
CALL AX
MOVL 4(SP), CX // restore original stack pointer
MOVL CX, SP
MOVL AX, ret+8(FP)
RET
// cgocallback(fn, frame unsafe.Pointer, ctxt uintptr)
// See cgocall.go for more details.
TEXT ·cgocallback(SB),NOSPLIT,$12-12 // Frame size must match commented places below
NO_LOCAL_POINTERS
// Skip cgocallbackg, just dropm when fn is nil, and frame is the saved g.
// It is used to dropm while thread is exiting.
MOVL fn+0(FP), AX
CMPL AX, $0
JNE loadg
// Restore the g from frame.
get_tls(CX)
MOVL frame+4(FP), BX
MOVL BX, g(CX)
JMP dropm
loadg:
// If g is nil, Go did not create the current thread,
// or if this thread never called into Go on pthread platforms.
// Call needm to obtain one for temporary use.
// In this case, we're running on the thread stack, so there's
// lots of space, but the linker doesn't know. Hide the call from
// the linker analysis by using an indirect call through AX.
get_tls(CX)
#ifdef GOOS_windows
MOVL $0, BP
CMPL CX, $0
JEQ 2(PC) // TODO
#endif
MOVL g(CX), BP
CMPL BP, $0
JEQ needm
MOVL g_m(BP), BP
MOVL BP, savedm-4(SP) // saved copy of oldm
JMP havem
needm:
MOVL $runtime·needAndBindM(SB), AX
CALL AX
MOVL $0, savedm-4(SP)
get_tls(CX)
MOVL g(CX), BP
MOVL g_m(BP), BP
// Set m->sched.sp = SP, so that if a panic happens
// during the function we are about to execute, it will
// have a valid SP to run on the g0 stack.
// The next few lines (after the havem label)
// will save this SP onto the stack and then write
// the same SP back to m->sched.sp. That seems redundant,
// but if an unrecovered panic happens, unwindm will
// restore the g->sched.sp from the stack location
// and then systemstack will try to use it. If we don't set it here,
// that restored SP will be uninitialized (typically 0) and
// will not be usable.
MOVL m_g0(BP), SI
MOVL SP, (g_sched+gobuf_sp)(SI)
havem:
// Now there's a valid m, and we're running on its m->g0.
// Save current m->g0->sched.sp on stack and then set it to SP.
// Save current sp in m->g0->sched.sp in preparation for
// switch back to m->curg stack.
// NOTE: unwindm knows that the saved g->sched.sp is at 0(SP).
MOVL m_g0(BP), SI
MOVL (g_sched+gobuf_sp)(SI), AX
MOVL AX, 0(SP)
MOVL SP, (g_sched+gobuf_sp)(SI)
// Switch to m->curg stack and call runtime.cgocallbackg.
// Because we are taking over the execution of m->curg
// but *not* resuming what had been running, we need to
// save that information (m->curg->sched) so we can restore it.
// We can restore m->curg->sched.sp easily, because calling
// runtime.cgocallbackg leaves SP unchanged upon return.
// To save m->curg->sched.pc, we push it onto the curg stack and
// open a frame the same size as cgocallback's g0 frame.
// Once we switch to the curg stack, the pushed PC will appear
// to be the return PC of cgocallback, so that the traceback
// will seamlessly trace back into the earlier calls.
MOVL m_curg(BP), SI
MOVL SI, g(CX)
MOVL (g_sched+gobuf_sp)(SI), DI // prepare stack as DI
MOVL (g_sched+gobuf_pc)(SI), BP
MOVL BP, -4(DI) // "push" return PC on the g stack
// Gather our arguments into registers.
MOVL fn+0(FP), AX
MOVL frame+4(FP), BX
MOVL ctxt+8(FP), CX
LEAL -(4+12)(DI), SP // Must match declared frame size
MOVL AX, 0(SP)
MOVL BX, 4(SP)
MOVL CX, 8(SP)
CALL runtime·cgocallbackg(SB)
// Restore g->sched (== m->curg->sched) from saved values.
get_tls(CX)
MOVL g(CX), SI
MOVL 12(SP), BP // Must match declared frame size
MOVL BP, (g_sched+gobuf_pc)(SI)
LEAL (12+4)(SP), DI // Must match declared frame size
MOVL DI, (g_sched+gobuf_sp)(SI)
// Switch back to m->g0's stack and restore m->g0->sched.sp.
// (Unlike m->curg, the g0 goroutine never uses sched.pc,
// so we do not have to restore it.)
MOVL g(CX), BP
MOVL g_m(BP), BP
MOVL m_g0(BP), SI
MOVL SI, g(CX)
MOVL (g_sched+gobuf_sp)(SI), SP
MOVL 0(SP), AX
MOVL AX, (g_sched+gobuf_sp)(SI)
// If the m on entry was nil, we called needm above to borrow an m,
// 1. for the duration of the call on non-pthread platforms,
// 2. or the duration of the C thread alive on pthread platforms.
// If the m on entry wasn't nil,
// 1. the thread might be a Go thread,
// 2. or it wasn't the first call from a C thread on pthread platforms,
// since then we skip dropm to reuse the m in the first call.
MOVL savedm-4(SP), DX
CMPL DX, $0
JNE droppedm
// Skip dropm to reuse it in the next call, when a pthread key has been created.
MOVL _cgo_pthread_key_created(SB), DX
// It means cgo is disabled when _cgo_pthread_key_created is a nil pointer, need dropm.
CMPL DX, $0
JEQ dropm
CMPL (DX), $0
JNE droppedm
dropm:
MOVL $runtime·dropm(SB), AX
CALL AX
droppedm:
// Done!
RET
// void setg(G*); set g. for use by needm.
TEXT runtime·setg(SB), NOSPLIT, $0-4
MOVL gg+0(FP), BX
#ifdef GOOS_windows
MOVL runtime·tls_g(SB), CX
CMPL BX, $0
JNE settls
MOVL $0, 0(CX)(FS)
RET
settls:
MOVL g_m(BX), AX
LEAL m_tls(AX), AX
MOVL AX, 0(CX)(FS)
#endif
get_tls(CX)
MOVL BX, g(CX)
RET
// void setg_gcc(G*); set g. for use by gcc
TEXT setg_gcc<>(SB), NOSPLIT, $0
get_tls(AX)
MOVL gg+0(FP), DX
MOVL DX, g(AX)
RET
TEXT runtime·abort(SB),NOSPLIT,$0-0
INT $3
loop:
JMP loop
// check that SP is in range [g->stack.lo, g->stack.hi)
TEXT runtime·stackcheck(SB), NOSPLIT, $0-0
get_tls(CX)
MOVL g(CX), AX
CMPL (g_stack+stack_hi)(AX), SP
JHI 2(PC)
CALL runtime·abort(SB)
CMPL SP, (g_stack+stack_lo)(AX)
JHI 2(PC)
CALL runtime·abort(SB)
RET
// func cputicks() int64
TEXT runtime·cputicks(SB),NOSPLIT,$0-8
// LFENCE/MFENCE instruction support is dependent on SSE2.
// When no SSE2 support is present do not enforce any serialization
// since using CPUID to serialize the instruction stream is
// very costly.
#ifdef GO386_softfloat
JMP rdtsc // no fence instructions available
#endif
CMPB internal∕cpu·X86+const_offsetX86HasRDTSCP(SB), $1
JNE fences
// Instruction stream serializing RDTSCP is supported.
// RDTSCP is supported by Intel Nehalem (2008) and
// AMD K8 Rev. F (2006) and newer.
RDTSCP
done:
MOVL AX, ret_lo+0(FP)
MOVL DX, ret_hi+4(FP)
RET
fences:
// MFENCE is instruction stream serializing and flushes the
// store buffers on AMD. The serialization semantics of LFENCE on AMD
// are dependent on MSR C001_1029 and CPU generation.
// LFENCE on Intel does wait for all previous instructions to have executed.
// Intel recommends MFENCE;LFENCE in its manuals before RDTSC to have all
// previous instructions executed and all previous loads and stores to globally visible.
// Using MFENCE;LFENCE here aligns the serializing properties without
// runtime detection of CPU manufacturer.
MFENCE
LFENCE
rdtsc:
RDTSC
JMP done
TEXT ldt0setup<>(SB),NOSPLIT,$16-0
#ifdef GOOS_windows
CALL runtime·wintls(SB)
#endif
// set up ldt 7 to point at m0.tls
// ldt 1 would be fine on Linux, but on OS X, 7 is as low as we can go.
// the entry number is just a hint. setldt will set up GS with what it used.
MOVL $7, 0(SP)
LEAL runtime·m0+m_tls(SB), AX
MOVL AX, 4(SP)
MOVL $32, 8(SP) // sizeof(tls array)
CALL runtime·setldt(SB)
RET
TEXT runtime·emptyfunc(SB),0,$0-0
RET
// hash function using AES hardware instructions
TEXT runtime·memhash(SB),NOSPLIT,$0-16
CMPB runtime·useAeshash(SB), $0
JEQ noaes
MOVL p+0(FP), AX // ptr to data
MOVL s+8(FP), BX // size
LEAL ret+12(FP), DX
JMP aeshashbody<>(SB)
noaes:
JMP runtime·memhashFallback(SB)
TEXT runtime·strhash(SB),NOSPLIT,$0-12
CMPB runtime·useAeshash(SB), $0
JEQ noaes
MOVL p+0(FP), AX // ptr to string object
MOVL 4(AX), BX // length of string
MOVL (AX), AX // string data
LEAL ret+8(FP), DX
JMP aeshashbody<>(SB)
noaes:
JMP runtime·strhashFallback(SB)
// AX: data
// BX: length
// DX: address to put return value
TEXT aeshashbody<>(SB),NOSPLIT,$0-0
MOVL h+4(FP), X0 // 32 bits of per-table hash seed
PINSRW $4, BX, X0 // 16 bits of length
PSHUFHW $0, X0, X0 // replace size with its low 2 bytes repeated 4 times
MOVO X0, X1 // save unscrambled seed
PXOR runtime·aeskeysched(SB), X0 // xor in per-process seed
AESENC X0, X0 // scramble seed
CMPL BX, $16
JB aes0to15
JE aes16
CMPL BX, $32
JBE aes17to32
CMPL BX, $64
JBE aes33to64
JMP aes65plus
aes0to15:
TESTL BX, BX
JE aes0
ADDL $16, AX
TESTW $0xff0, AX
JE endofpage
// 16 bytes loaded at this address won't cross