summaryrefslogtreecommitdiffstats
path: root/src/runtime/asm_amd64.s
blob: d2f798417898bc91578ecb793b577607539f7d5e (plain)
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
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
// 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"
#include "cgo/abi_amd64.h"

// _rt0_amd64 is common startup code for most amd64 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_amd64(SB),NOSPLIT,$-8
	MOVQ	0(SP), DI	// argc
	LEAQ	8(SP), SI	// argv
	JMP	runtime·rt0_go(SB)

// main is common startup code for most amd64 systems when using
// external linking. The C startup code will call the symbol "main"
// passing argc and argv in the usual C ABI registers DI and SI.
TEXT main(SB),NOSPLIT,$-8
	JMP	runtime·rt0_go(SB)

// _rt0_amd64_lib is common startup code for most amd64 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 in the usual C ABI registers
// DI and SI.
TEXT _rt0_amd64_lib(SB),NOSPLIT,$0
	// Transition from C ABI to Go ABI.
	PUSH_REGS_HOST_TO_ABI0()

	MOVQ	DI, _rt0_amd64_lib_argc<>(SB)
	MOVQ	SI, _rt0_amd64_lib_argv<>(SB)

	// Synchronous initialization.
	CALL	runtime·libpreinit(SB)

	// Create a new thread to finish Go runtime initialization.
	MOVQ	_cgo_sys_thread_create(SB), AX
	TESTQ	AX, AX
	JZ	nocgo

	// We're calling back to C.
	// Align stack per ELF ABI requirements.
	MOVQ	SP, BX  // Callee-save in C ABI
	ANDQ	$~15, SP
	MOVQ	$_rt0_amd64_lib_go(SB), DI
	MOVQ	$0, SI
	CALL	AX
	MOVQ	BX, SP
	JMP	restore

nocgo:
	ADJSP	$16
	MOVQ	$0x800000, 0(SP)		// stacksize
	MOVQ	$_rt0_amd64_lib_go(SB), AX
	MOVQ	AX, 8(SP)			// fn
	CALL	runtime·newosproc0(SB)
	ADJSP	$-16

restore:
	POP_REGS_HOST_TO_ABI0()
	RET

// _rt0_amd64_lib_go initializes the Go runtime.
// This is started in a separate thread by _rt0_amd64_lib.
TEXT _rt0_amd64_lib_go(SB),NOSPLIT,$0
	MOVQ	_rt0_amd64_lib_argc<>(SB), DI
	MOVQ	_rt0_amd64_lib_argv<>(SB), SI
	JMP	runtime·rt0_go(SB)

DATA _rt0_amd64_lib_argc<>(SB)/8, $0
GLOBL _rt0_amd64_lib_argc<>(SB),NOPTR, $8
DATA _rt0_amd64_lib_argv<>(SB)/8, $0
GLOBL _rt0_amd64_lib_argv<>(SB),NOPTR, $8

#ifdef GOAMD64_v2
DATA bad_cpu_msg<>+0x00(SB)/84, $"This program can only be run on AMD64 processors with v2 microarchitecture support.\n"
#endif

#ifdef GOAMD64_v3
DATA bad_cpu_msg<>+0x00(SB)/84, $"This program can only be run on AMD64 processors with v3 microarchitecture support.\n"
#endif

#ifdef GOAMD64_v4
DATA bad_cpu_msg<>+0x00(SB)/84, $"This program can only be run on AMD64 processors with v4 microarchitecture support.\n"
#endif

GLOBL bad_cpu_msg<>(SB), RODATA, $84

// Define a list of AMD64 microarchitecture level features
// https://en.wikipedia.org/wiki/X86-64#Microarchitecture_levels

                     // SSE3     SSSE3    CMPXCHNG16 SSE4.1    SSE4.2    POPCNT
#define V2_FEATURES_CX (1 << 0 | 1 << 9 | 1 << 13  | 1 << 19 | 1 << 20 | 1 << 23)
                         // LAHF/SAHF
#define V2_EXT_FEATURES_CX (1 << 0)
                                      // FMA       MOVBE     OSXSAVE   AVX       F16C
#define V3_FEATURES_CX (V2_FEATURES_CX | 1 << 12 | 1 << 22 | 1 << 27 | 1 << 28 | 1 << 29)
                                              // ABM (FOR LZNCT)
#define V3_EXT_FEATURES_CX (V2_EXT_FEATURES_CX | 1 << 5)
                         // BMI1     AVX2     BMI2
#define V3_EXT_FEATURES_BX (1 << 3 | 1 << 5 | 1 << 8)
                       // XMM      YMM
#define V3_OS_SUPPORT_AX (1 << 1 | 1 << 2)

#define V4_FEATURES_CX V3_FEATURES_CX

#define V4_EXT_FEATURES_CX V3_EXT_FEATURES_CX
                                              // AVX512F   AVX512DQ  AVX512CD  AVX512BW  AVX512VL
#define V4_EXT_FEATURES_BX (V3_EXT_FEATURES_BX | 1 << 16 | 1 << 17 | 1 << 28 | 1 << 30 | 1 << 31)
                                          // OPMASK   ZMM
#define V4_OS_SUPPORT_AX (V3_OS_SUPPORT_AX | 1 << 5 | (1 << 6 | 1 << 7))

#ifdef GOAMD64_v2
#define NEED_MAX_CPUID 0x80000001
#define NEED_FEATURES_CX V2_FEATURES_CX
#define NEED_EXT_FEATURES_CX V2_EXT_FEATURES_CX
#endif

#ifdef GOAMD64_v3
#define NEED_MAX_CPUID 0x80000001
#define NEED_FEATURES_CX V3_FEATURES_CX
#define NEED_EXT_FEATURES_CX V3_EXT_FEATURES_CX
#define NEED_EXT_FEATURES_BX V3_EXT_FEATURES_BX
#define NEED_OS_SUPPORT_AX V3_OS_SUPPORT_AX
#endif

#ifdef GOAMD64_v4
#define NEED_MAX_CPUID 0x80000001
#define NEED_FEATURES_CX V4_FEATURES_CX
#define NEED_EXT_FEATURES_CX V4_EXT_FEATURES_CX
#define NEED_EXT_FEATURES_BX V4_EXT_FEATURES_BX

// Darwin requires a different approach to check AVX512 support, see CL 285572.
#ifdef GOOS_darwin
#define NEED_OS_SUPPORT_AX V3_OS_SUPPORT_AX
// These values are from:
// https://github.com/apple/darwin-xnu/blob/xnu-4570.1.46/osfmk/i386/cpu_capabilities.h
#define commpage64_base_address         0x00007fffffe00000
#define commpage64_cpu_capabilities64   (commpage64_base_address+0x010)
#define commpage64_version              (commpage64_base_address+0x01E)
#define hasAVX512F                      0x0000004000000000
#define hasAVX512CD                     0x0000008000000000
#define hasAVX512DQ                     0x0000010000000000
#define hasAVX512BW                     0x0000020000000000
#define hasAVX512VL                     0x0000100000000000
#define NEED_DARWIN_SUPPORT             (hasAVX512F | hasAVX512DQ | hasAVX512CD | hasAVX512BW | hasAVX512VL)
#else
#define NEED_OS_SUPPORT_AX V4_OS_SUPPORT_AX
#endif

#endif

TEXT runtime·rt0_go(SB),NOSPLIT|TOPFRAME,$0
	// copy arguments forward on an even stack
	MOVQ	DI, AX		// argc
	MOVQ	SI, BX		// argv
	SUBQ	$(5*8), SP		// 3args 2auto
	ANDQ	$~15, SP
	MOVQ	AX, 24(SP)
	MOVQ	BX, 32(SP)

	// create istack out of the given (operating system) stack.
	// _cgo_init may update stackguard.
	MOVQ	$runtime·g0(SB), DI
	LEAQ	(-64*1024+104)(SP), BX
	MOVQ	BX, g_stackguard0(DI)
	MOVQ	BX, g_stackguard1(DI)
	MOVQ	BX, (g_stack+stack_lo)(DI)
	MOVQ	SP, (g_stack+stack_hi)(DI)

	// find out information about the processor we're on
	MOVL	$0, AX
	CPUID
	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	AX, runtime·processorVersionInfo(SB)

nocpuinfo:
	// if there is an _cgo_init, call it.
	MOVQ	_cgo_init(SB), AX
	TESTQ	AX, AX
	JZ	needtls
	// arg 1: g0, already in DI
	MOVQ	$setg_gcc<>(SB), SI // arg 2: setg_gcc
#ifdef GOOS_android
	MOVQ	$runtime·tls_g(SB), DX 	// arg 3: &tls_g
	// arg 4: TLS base, stored in slot 0 (Android's TLS_SLOT_SELF).
	// Compensate for tls_g (+16).
	MOVQ	-16(TLS), CX
#else
	MOVQ	$0, DX	// arg 3, 4: not used when using platform's TLS
	MOVQ	$0, CX
#endif
#ifdef GOOS_windows
	// Adjust for the Win64 calling convention.
	MOVQ	CX, R9 // arg 4
	MOVQ	DX, R8 // arg 3
	MOVQ	SI, DX // arg 2
	MOVQ	DI, CX // arg 1
#endif
	CALL	AX

	// update stackguard after _cgo_init
	MOVQ	$runtime·g0(SB), CX
	MOVQ	(g_stack+stack_lo)(CX), AX
	ADDQ	$const__StackGuard, AX
	MOVQ	AX, g_stackguard0(CX)
	MOVQ	AX, g_stackguard1(CX)

#ifndef GOOS_windows
	JMP ok
#endif
needtls:
#ifdef GOOS_plan9
	// skip TLS setup on Plan 9
	JMP ok
#endif
#ifdef GOOS_solaris
	// skip TLS setup on Solaris
	JMP ok
#endif
#ifdef GOOS_illumos
	// skip TLS setup on illumos
	JMP ok
#endif
#ifdef GOOS_darwin
	// skip TLS setup on Darwin
	JMP ok
#endif
#ifdef GOOS_openbsd
	// skip TLS setup on OpenBSD
	JMP ok
#endif

	LEAQ	runtime·m0+m_tls(SB), DI
	CALL	runtime·settls(SB)

	// store through it, to make sure it works
	get_tls(BX)
	MOVQ	$0x123, g(BX)
	MOVQ	runtime·m0+m_tls(SB), AX
	CMPQ	AX, $0x123
	JEQ 2(PC)
	CALL	runtime·abort(SB)
ok:
	// set the per-goroutine and per-mach "registers"
	get_tls(BX)
	LEAQ	runtime·g0(SB), CX
	MOVQ	CX, g(BX)
	LEAQ	runtime·m0(SB), AX

	// save m->g0 = g0
	MOVQ	CX, m_g0(AX)
	// save m0 to g0->m
	MOVQ	AX, g_m(CX)

	CLD				// convention is D is always left cleared

	// Check GOAMD64 reqirements
	// We need to do this after setting up TLS, so that
	// we can report an error if there is a failure. See issue 49586.
#ifdef NEED_FEATURES_CX
	MOVL	$0, AX
	CPUID
	CMPL	AX, $0
	JE	bad_cpu
	MOVL	$1, AX
	CPUID
	ANDL	$NEED_FEATURES_CX, CX
	CMPL	CX, $NEED_FEATURES_CX
	JNE	bad_cpu
#endif

#ifdef NEED_MAX_CPUID
	MOVL	$0x80000000, AX
	CPUID
	CMPL	AX, $NEED_MAX_CPUID
	JL	bad_cpu
#endif

#ifdef NEED_EXT_FEATURES_BX
	MOVL	$7, AX
	MOVL	$0, CX
	CPUID
	ANDL	$NEED_EXT_FEATURES_BX, BX
	CMPL	BX, $NEED_EXT_FEATURES_BX
	JNE	bad_cpu
#endif

#ifdef NEED_EXT_FEATURES_CX
	MOVL	$0x80000001, AX
	CPUID
	ANDL	$NEED_EXT_FEATURES_CX, CX
	CMPL	CX, $NEED_EXT_FEATURES_CX
	JNE	bad_cpu
#endif

#ifdef NEED_OS_SUPPORT_AX
	XORL    CX, CX
	XGETBV
	ANDL	$NEED_OS_SUPPORT_AX, AX
	CMPL	AX, $NEED_OS_SUPPORT_AX
	JNE	bad_cpu
#endif

#ifdef NEED_DARWIN_SUPPORT
	MOVQ	$commpage64_version, BX
	CMPW	(BX), $13  // cpu_capabilities64 undefined in versions < 13
	JL	bad_cpu
	MOVQ	$commpage64_cpu_capabilities64, BX
	MOVQ	(BX), BX
	MOVQ	$NEED_DARWIN_SUPPORT, CX
	ANDQ	CX, BX
	CMPQ	BX, CX
	JNE	bad_cpu
#endif

	CALL	runtime·check(SB)

	MOVL	24(SP), AX		// copy argc
	MOVL	AX, 0(SP)
	MOVQ	32(SP), AX		// copy argv
	MOVQ	AX, 8(SP)
	CALL	runtime·args(SB)
	CALL	runtime·osinit(SB)
	CALL	runtime·schedinit(SB)

	// create a new goroutine to start program
	MOVQ	$runtime·mainPC(SB), AX		// entry
	PUSHQ	AX
	CALL	runtime·newproc(SB)
	POPQ	AX

	// start this M
	CALL	runtime·mstart(SB)

	CALL	runtime·abort(SB)	// mstart should never return
	RET

bad_cpu: // show that the program requires a certain microarchitecture level.
	MOVQ	$2, 0(SP)
	MOVQ	$bad_cpu_msg<>(SB), AX
	MOVQ	AX, 8(SP)
	MOVQ	$84, 16(SP)
	CALL	runtime·write(SB)
	MOVQ	$1, 0(SP)
	CALL	runtime·exit(SB)
	CALL	runtime·abort(SB)
	RET

	// Prevent dead-code elimination of debugCallV2, which is
	// intended to be called by debuggers.
	MOVQ	$runtime·debugCallV2<ABIInternal>(SB), AX
	RET

// mainPC is a function value for runtime.main, to be passed to newproc.
// The reference to runtime.main is made via ABIInternal, since the
// actual function (not the ABI0 wrapper) is needed by newproc.
DATA	runtime·mainPC+0(SB)/8,$runtime·main<ABIInternal>(SB)
GLOBL	runtime·mainPC(SB),RODATA,$8

TEXT runtime·breakpoint(SB),NOSPLIT,$0-0
	BYTE	$0xcc
	RET

TEXT runtime·asminit(SB),NOSPLIT,$0-0
	// No per-thread init.
	RET

TEXT runtime·mstart(SB),NOSPLIT|TOPFRAME,$0
	CALL	runtime·mstart0(SB)
	RET // not reached

/*
 *  go-routine
 */

// func gogo(buf *gobuf)
// restore state from Gobuf; longjmp
TEXT runtime·gogo(SB), NOSPLIT, $0-8
	MOVQ	buf+0(FP), BX		// gobuf
	MOVQ	gobuf_g(BX), DX
	MOVQ	0(DX), CX		// make sure g != nil
	JMP	gogo<>(SB)

TEXT gogo<>(SB), NOSPLIT, $0
	get_tls(CX)
	MOVQ	DX, g(CX)
	MOVQ	DX, R14		// set the g register
	MOVQ	gobuf_sp(BX), SP	// restore SP
	MOVQ	gobuf_ret(BX), AX
	MOVQ	gobuf_ctxt(BX), DX
	MOVQ	gobuf_bp(BX), BP
	MOVQ	$0, gobuf_sp(BX)	// clear to help garbage collector
	MOVQ	$0, gobuf_ret(BX)
	MOVQ	$0, gobuf_ctxt(BX)
	MOVQ	$0, gobuf_bp(BX)
	MOVQ	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<ABIInternal>(SB), NOSPLIT, $0-8
	MOVQ	AX, DX	// DX = fn

	// save state in g->sched
	MOVQ	0(SP), BX	// caller's PC
	MOVQ	BX, (g_sched+gobuf_pc)(R14)
	LEAQ	fn+0(FP), BX	// caller's SP
	MOVQ	BX, (g_sched+gobuf_sp)(R14)
	MOVQ	BP, (g_sched+gobuf_bp)(R14)

	// switch to m->g0 & its stack, call fn
	MOVQ	g_m(R14), BX
	MOVQ	m_g0(BX), SI	// SI = g.m.g0
	CMPQ	SI, R14	// if g == m->g0 call badmcall
	JNE	goodm
	JMP	runtime·badmcall(SB)
goodm:
	MOVQ	R14, AX		// AX (and arg 0) = g
	MOVQ	SI, R14		// g = g.m.g0
	get_tls(CX)		// Set G in TLS
	MOVQ	R14, g(CX)
	MOVQ	(g_sched+gobuf_sp)(R14), SP	// sp = g0.sched.sp
	PUSHQ	AX	// open up space for fn's arg spill slot
	MOVQ	0(DX), R12
	CALL	R12		// fn(g)
	POPQ	AX
	JMP	runtime·badmcall2(SB)
	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, $0-8
	MOVQ	fn+0(FP), DI	// DI = fn
	get_tls(CX)
	MOVQ	g(CX), AX	// AX = g
	MOVQ	g_m(AX), BX	// BX = m

	CMPQ	AX, m_gsignal(BX)
	JEQ	noswitch

	MOVQ	m_g0(BX), DX	// DX = g0
	CMPQ	AX, DX
	JEQ	noswitch

	CMPQ	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
	MOVQ	DX, g(CX)
	MOVQ	DX, R14 // set the g register
	MOVQ	(g_sched+gobuf_sp)(DX), BX
	MOVQ	BX, SP

	// call target function
	MOVQ	DI, DX
	MOVQ	0(DI), DI
	CALL	DI

	// switch back to g
	get_tls(CX)
	MOVQ	g(CX), AX
	MOVQ	g_m(AX), BX
	MOVQ	m_curg(BX), AX
	MOVQ	AX, g(CX)
	MOVQ	(g_sched+gobuf_sp)(AX), SP
	MOVQ	$0, (g_sched+gobuf_sp)(AX)
	RET

noswitch:
	// already on m stack; tail call the function
	// Using a tail call here cleans up tracebacks since we won't stop
	// at an intermediate systemstack.
	MOVQ	DI, DX
	MOVQ	0(DI), DI
	JMP	DI

bad:
	// Bad: g is not gsignal, not g0, not curg. What is it?
	MOVQ	$runtime·badsystemstack(SB), AX
	CALL	AX
	INT	$3


/*
 * 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,$0-0
	// Cannot grow scheduler stack (m->g0).
	get_tls(CX)
	MOVQ	g(CX), BX
	MOVQ	g_m(BX), BX
	MOVQ	m_g0(BX), SI
	CMPQ	g(CX), SI
	JNE	3(PC)
	CALL	runtime·badmorestackg0(SB)
	CALL	runtime·abort(SB)

	// Cannot grow signal stack (m->gsignal).
	MOVQ	m_gsignal(BX), SI
	CMPQ	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
	MOVQ	8(SP), AX	// f's caller's PC
	MOVQ	AX, (m_morebuf+gobuf_pc)(BX)
	LEAQ	16(SP), AX	// f's caller's SP
	MOVQ	AX, (m_morebuf+gobuf_sp)(BX)
	get_tls(CX)
	MOVQ	g(CX), SI
	MOVQ	SI, (m_morebuf+gobuf_g)(BX)

	// Set g->sched to context in f.
	MOVQ	0(SP), AX // f's PC
	MOVQ	AX, (g_sched+gobuf_pc)(SI)
	LEAQ	8(SP), AX // f's SP
	MOVQ	AX, (g_sched+gobuf_sp)(SI)
	MOVQ	BP, (g_sched+gobuf_bp)(SI)
	MOVQ	DX, (g_sched+gobuf_ctxt)(SI)

	// Call newstack on m->g0's stack.
	MOVQ	m_g0(BX), BX
	MOVQ	BX, g(CX)
	MOVQ	(g_sched+gobuf_sp)(BX), SP
	CALL	runtime·newstack(SB)
	CALL	runtime·abort(SB)	// crash if newstack returns
	RET

// morestack but not preserving ctxt.
TEXT runtime·morestack_noctxt(SB),NOSPLIT,$0
	MOVL	$0, DX
	JMP	runtime·morestack(SB)

// spillArgs stores return values from registers to a *internal/abi.RegArgs in R12.
TEXT ·spillArgs(SB),NOSPLIT,$0-0
	MOVQ AX, 0(R12)
	MOVQ BX, 8(R12)
	MOVQ CX, 16(R12)
	MOVQ DI, 24(R12)
	MOVQ SI, 32(R12)
	MOVQ R8, 40(R12)
	MOVQ R9, 48(R12)
	MOVQ R10, 56(R12)
	MOVQ R11, 64(R12)
	MOVQ X0, 72(R12)
	MOVQ X1, 80(R12)
	MOVQ X2, 88(R12)
	MOVQ X3, 96(R12)
	MOVQ X4, 104(R12)
	MOVQ X5, 112(R12)
	MOVQ X6, 120(R12)
	MOVQ X7, 128(R12)
	MOVQ X8, 136(R12)
	MOVQ X9, 144(R12)
	MOVQ X10, 152(R12)
	MOVQ X11, 160(R12)
	MOVQ X12, 168(R12)
	MOVQ X13, 176(R12)
	MOVQ X14, 184(R12)
	RET

// unspillArgs loads args into registers from a *internal/abi.RegArgs in R12.
TEXT ·unspillArgs(SB),NOSPLIT,$0-0
	MOVQ 0(R12), AX
	MOVQ 8(R12), BX
	MOVQ 16(R12), CX
	MOVQ 24(R12), DI
	MOVQ 32(R12), SI
	MOVQ 40(R12), R8
	MOVQ 48(R12), R9
	MOVQ 56(R12), R10
	MOVQ 64(R12), R11
	MOVQ 72(R12), X0
	MOVQ 80(R12), X1
	MOVQ 88(R12), X2
	MOVQ 96(R12), X3
	MOVQ 104(R12), X4
	MOVQ 112(R12), X5
	MOVQ 120(R12), X6
	MOVQ 128(R12), X7
	MOVQ 136(R12), X8
	MOVQ 144(R12), X9
	MOVQ 152(R12), X10
	MOVQ 160(R12), X11
	MOVQ 168(R12), X12
	MOVQ 176(R12), X13
	MOVQ 184(R12), X14
	RET

// 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)		\
	CMPQ	CX, $MAXSIZE;		\
	JA	3(PC);			\
	MOVQ	$NAME(SB), AX;		\
	JMP	AX
// Note: can't just "JMP NAME(SB)" - bad inlining results.

TEXT ·reflectcall(SB), NOSPLIT, $0-48
	MOVLQZX frameSize+32(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)
	MOVQ	$runtime·badreflectcall(SB), AX
	JMP	AX

#define CALLFN(NAME,MAXSIZE)			\
TEXT NAME(SB), WRAPPER, $MAXSIZE-48;		\
	NO_LOCAL_POINTERS;			\
	/* copy arguments to stack */		\
	MOVQ	stackArgs+16(FP), SI;		\
	MOVLQZX stackArgsSize+24(FP), CX;		\
	MOVQ	SP, DI;				\
	REP;MOVSB;				\
	/* set up argument registers */		\
	MOVQ    regArgs+40(FP), R12;		\
	CALL    ·unspillArgs(SB);		\
	/* call function */			\
	MOVQ	f+8(FP), DX;			\
	PCDATA  $PCDATA_StackMapIndex, $0;	\
	MOVQ	(DX), R12;			\
	CALL	R12;				\
	/* copy register return values back */		\
	MOVQ    regArgs+40(FP), R12;		\
	CALL    ·spillArgs(SB);		\
	MOVLQZX	stackArgsSize+24(FP), CX;		\
	MOVLQZX	stackRetOffset+28(FP), BX;		\
	MOVQ	stackArgs+16(FP), DI;		\
	MOVQ	stackArgsType+0(FP), DX;		\
	MOVQ	SP, SI;				\
	ADDQ	BX, DI;				\
	ADDQ	BX, SI;				\
	SUBQ	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, $40-0
	NO_LOCAL_POINTERS
	MOVQ	DX, 0(SP)
	MOVQ	DI, 8(SP)
	MOVQ	SI, 16(SP)
	MOVQ	CX, 24(SP)
	MOVQ	R12, 32(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.
// Smashes R9.
TEXT gosave_systemstack_switch<>(SB),NOSPLIT,$0
	MOVQ	$runtime·systemstack_switch(SB), R9
	MOVQ	R9, (g_sched+gobuf_pc)(R14)
	LEAQ	8(SP), R9
	MOVQ	R9, (g_sched+gobuf_sp)(R14)
	MOVQ	$0, (g_sched+gobuf_ret)(R14)
	MOVQ	BP, (g_sched+gobuf_bp)(R14)
	// Assert ctxt is zero. See func save.
	MOVQ	(g_sched+gobuf_ctxt)(R14), R9
	TESTQ	R9, R9
	JZ	2(PC)
	CALL	runtime·abort(SB)
	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,$0-16
	MOVQ	fn+0(FP), AX
	MOVQ	arg+8(FP), BX
	MOVQ	SP, DX
	SUBQ	$32, SP
	ANDQ	$~15, SP	// alignment
	MOVQ	DX, 8(SP)
	MOVQ	BX, DI		// DI = first argument in AMD64 ABI
	MOVQ	BX, CX		// CX = first argument in Win64
	CALL	AX
	MOVQ	8(SP), DX
	MOVQ	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,$0-20
	MOVQ	fn+0(FP), AX
	MOVQ	arg+8(FP), BX

	MOVQ	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)
	MOVQ	g(CX), DI
	CMPQ	DI, $0
	JEQ	nosave
	MOVQ	g_m(DI), R8
	MOVQ	m_gsignal(R8), SI
	CMPQ	DI, SI
	JEQ	nosave
	MOVQ	m_g0(R8), SI
	CMPQ	DI, SI
	JEQ	nosave

	// Switch to system stack.
	CALL	gosave_systemstack_switch<>(SB)
	MOVQ	SI, g(CX)
	MOVQ	(g_sched+gobuf_sp)(SI), SP

	// Now on a scheduling stack (a pthread-created stack).
	// Make sure we have enough room for 4 stack-backed fast-call
	// registers as per windows amd64 calling convention.
	SUBQ	$64, SP
	ANDQ	$~15, SP	// alignment for gcc ABI
	MOVQ	DI, 48(SP)	// save g
	MOVQ	(g_stack+stack_hi)(DI), DI
	SUBQ	DX, DI
	MOVQ	DI, 40(SP)	// save depth in stack (can't just save SP, as stack might be copied during a callback)
	MOVQ	BX, DI		// DI = first argument in AMD64 ABI
	MOVQ	BX, CX		// CX = first argument in Win64
	CALL	AX

	// Restore registers, g, stack pointer.
	get_tls(CX)
	MOVQ	48(SP), DI
	MOVQ	(g_stack+stack_hi)(DI), SI
	SUBQ	40(SP), SI
	MOVQ	DI, g(CX)
	MOVQ	SI, SP

	MOVL	AX, ret+16(FP)
	RET

nosave:
	// Running on a system stack, perhaps even without a g.
	// Having no g can happen during thread creation or thread teardown
	// (see needm/dropm on Solaris, for example).
	// This code is like the above sequence but without saving/restoring g
	// and without worrying about the stack moving out from under us
	// (because we're on a system stack, not a goroutine stack).
	// The above code could be used directly if already on a system stack,
	// but then the only path through this code would be a rare case on Solaris.
	// Using this code for all "already on system stack" calls exercises it more,
	// which should help keep it correct.
	SUBQ	$64, SP
	ANDQ	$~15, SP
	MOVQ	$0, 48(SP)		// where above code stores g, in case someone looks during debugging
	MOVQ	DX, 40(SP)	// save original stack pointer
	MOVQ	BX, DI		// DI = first argument in AMD64 ABI
	MOVQ	BX, CX		// CX = first argument in Win64
	CALL	AX
	MOVQ	40(SP), SI	// restore original stack pointer
	MOVQ	SI, SP
	MOVL	AX, ret+16(FP)
	RET

#ifdef GOOS_windows
// Dummy TLS that's used on Windows so that we don't crash trying
// to restore the G register in needm. needm and its callees are
// very careful never to actually use the G, the TLS just can't be
// unset since we're in Go code.
GLOBL zeroTLS<>(SB),RODATA,$const_tlsSize
#endif

// func cgocallback(fn, frame unsafe.Pointer, ctxt uintptr)
// See cgocall.go for more details.
TEXT ·cgocallback(SB),NOSPLIT,$24-24
	NO_LOCAL_POINTERS

	// If g is nil, Go did not create the current thread.
	// Call needm to obtain one m 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, BX
	CMPQ	CX, $0
	JEQ	2(PC)
#endif
	MOVQ	g(CX), BX
	CMPQ	BX, $0
	JEQ	needm
	MOVQ	g_m(BX), BX
	MOVQ	BX, savedm-8(SP)	// saved copy of oldm
	JMP	havem
needm:
#ifdef GOOS_windows
	// Set up a dummy TLS value. needm is careful not to use it,
	// but it needs to be there to prevent autogenerated code from
	// crashing when it loads from it.
	// We don't need to clear it or anything later because needm
	// will set up TLS properly.
	MOVQ	$zeroTLS<>(SB), DI
	CALL	runtime·settls(SB)
#endif
	// On some platforms (Windows) we cannot call needm through
	// an ABI wrapper because there's no TLS set up, and the ABI
	// wrapper will try to restore the G register (R14) from TLS.
	// Clear X15 because Go expects it and we're not calling
	// through a wrapper, but otherwise avoid setting the G
	// register in the wrapper and call needm directly. It
	// takes no arguments and doesn't return any values so
	// there's no need to handle that. Clear R14 so that there's
	// a bad value in there, in case needm tries to use it.
	XORPS	X15, X15
	XORQ    R14, R14
	MOVQ	$runtime·needm<ABIInternal>(SB), AX
	CALL	AX
	MOVQ	$0, savedm-8(SP) // dropm on return
	get_tls(CX)
	MOVQ	g(CX), BX
	MOVQ	g_m(BX), BX

	// 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.
	MOVQ	m_g0(BX), SI
	MOVQ	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).
	MOVQ	m_g0(BX), SI
	MOVQ	(g_sched+gobuf_sp)(SI), AX
	MOVQ	AX, 0(SP)
	MOVQ	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.
	MOVQ	m_curg(BX), SI
	MOVQ	SI, g(CX)
	MOVQ	(g_sched+gobuf_sp)(SI), DI  // prepare stack as DI
	MOVQ	(g_sched+gobuf_pc)(SI), BX
	MOVQ	BX, -8(DI)  // "push" return PC on the g stack
	// Gather our arguments into registers.
	MOVQ	fn+0(FP), BX
	MOVQ	frame+8(FP), CX
	MOVQ	ctxt+16(FP), DX
	// Compute the size of the frame, including return PC and, if
	// GOEXPERIMENT=framepointer, the saved base pointer
	LEAQ	fn+0(FP), AX
	SUBQ	SP, AX   // AX is our actual frame size
	SUBQ	AX, DI   // Allocate the same frame size on the g stack
	MOVQ	DI, SP

	MOVQ	BX, 0(SP)
	MOVQ	CX, 8(SP)
	MOVQ	DX, 16(SP)
	MOVQ	$runtime·cgocallbackg(SB), AX
	CALL	AX	// indirect call to bypass nosplit check. We're on a different stack now.

	// Compute the size of the frame again. FP and SP have
	// completely different values here than they did above,
	// but only their difference matters.
	LEAQ	fn+0(FP), AX
	SUBQ	SP, AX

	// Restore g->sched (== m->curg->sched) from saved values.
	get_tls(CX)
	MOVQ	g(CX), SI
	MOVQ	SP, DI
	ADDQ	AX, DI
	MOVQ	-8(DI), BX
	MOVQ	BX, (g_sched+gobuf_pc)(SI)
	MOVQ	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.)
	MOVQ	g(CX), BX
	MOVQ	g_m(BX), BX
	MOVQ	m_g0(BX), SI
	MOVQ	SI, g(CX)
	MOVQ	(g_sched+gobuf_sp)(SI), SP
	MOVQ	0(SP), AX
	MOVQ	AX, (g_sched+gobuf_sp)(SI)

	// If the m on entry was nil, we called needm above to borrow an m
	// for the duration of the call. Since the call is over, return it with dropm.
	MOVQ	savedm-8(SP), BX
	CMPQ	BX, $0
	JNE	done
	MOVQ	$runtime·dropm(SB), AX
	CALL	AX
#ifdef GOOS_windows
	// We need to clear the TLS pointer in case the next
	// thread that comes into Go tries to reuse that space
	// but uses the same M.
	XORQ	DI, DI
	CALL	runtime·settls(SB)
#endif
done:

	// Done!
	RET

// func setg(gg *g)
// set g. for use by needm.
TEXT runtime·setg(SB), NOSPLIT, $0-8
	MOVQ	gg+0(FP), BX
	get_tls(CX)
	MOVQ	BX, g(CX)
	RET

// void setg_gcc(G*); set g called from gcc.
TEXT setg_gcc<>(SB),NOSPLIT,$0
	get_tls(AX)
	MOVQ	DI, g(AX)
	MOVQ	DI, R14 // set the g register
	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)
	MOVQ	g(CX), AX
	CMPQ	(g_stack+stack_hi)(AX), SP
	JHI	2(PC)
	CALL	runtime·abort(SB)
	CMPQ	SP, (g_stack+stack_lo)(AX)
	JHI	2(PC)
	CALL	runtime·abort(SB)
	RET

// func cputicks() int64
TEXT runtime·cputicks(SB),NOSPLIT,$0-0
	CMPB	internalcpu·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:
	SHLQ	$32, DX
	ADDQ	DX, AX
	MOVQ	AX, ret+0(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
	JMP done

// func memhash(p unsafe.Pointer, h, s uintptr) uintptr
// hash function using AES hardware instructions
TEXT runtime·memhash<ABIInternal>(SB),NOSPLIT,$0-32
	// AX = ptr to data
	// BX = seed
	// CX = size
	CMPB	runtime·useAeshash(SB), $0
	JEQ	noaes
	JMP	aeshashbody<>(SB)
noaes:
	JMP	runtime·memhashFallback<ABIInternal>(SB)

// func strhash(p unsafe.Pointer, h uintptr) uintptr
TEXT runtime·strhash<ABIInternal>(SB),NOSPLIT,$0-24
	// AX = ptr to string struct
	// BX = seed
	CMPB	runtime·useAeshash(SB), $0
	JEQ	noaes
	MOVQ	8(AX), CX	// length of string
	MOVQ	(AX), AX	// string data
	JMP	aeshashbody<>(SB)
noaes:
	JMP	runtime·strhashFallback<ABIInternal>(SB)

// AX: data
// BX: hash seed
// CX: length
// At return: AX = return value
TEXT aeshashbody<>(SB),NOSPLIT,$0-0
	// Fill an SSE register with our seeds.
	MOVQ	BX, X0				// 64 bits of per-table hash seed
	PINSRW	$4, CX, X0			// 16 bits of length
	PSHUFHW $0, X0, X0			// repeat length 4 times total
	MOVO	X0, X1				// save unscrambled seed
	PXOR	runtime·aeskeysched(SB), X0	// xor in per-process seed
	AESENC	X0, X0				// scramble seed

	CMPQ	CX, $16
	JB	aes0to15
	JE	aes16
	CMPQ	CX, $32
	JBE	aes17to32
	CMPQ	CX, $64
	JBE	aes33to64
	CMPQ	CX, $128
	JBE	aes65to128
	JMP	aes129plus

aes0to15:
	TESTQ	CX, CX
	JE	aes0

	ADDQ	$16, AX
	TESTW	$0xff0, AX
	JE	endofpage

	// 16 bytes loaded at this address won't cross
	// a page boundary, so we can load it directly.
	MOVOU	-16(AX), X1
	ADDQ	CX, CX
	MOVQ	$masks<>(SB), AX
	PAND	(AX)(CX*8), X1
final1:
	PXOR	X0, X1	// xor data with seed
	AESENC	X1, X1	// scramble combo 3 times
	AESENC	X1, X1
	AESENC	X1, X1
	MOVQ	X1, AX	// return X1
	RET

endofpage:
	// address ends in 1111xxxx. Might be up against
	// a page boundary, so load ending at last byte.
	// Then shift bytes down using pshufb.
	MOVOU	-32(AX)(CX*1), X1
	ADDQ	CX, CX
	MOVQ	$shifts<>(SB), AX
	PSHUFB	(AX)(CX*8), X1
	JMP	final1

aes0:
	// Return scrambled input seed
	AESENC	X0, X0
	MOVQ	X0, AX	// return X0
	RET

aes16:
	MOVOU	(AX), X1
	JMP	final1

aes17to32:
	// make second starting seed
	PXOR	runtime·aeskeysched+16(SB), X1
	AESENC	X1, X1

	// load data to be hashed
	MOVOU	(AX), X2
	MOVOU	-16(AX)(CX*1), X3

	// xor with seed
	PXOR	X0, X2
	PXOR	X1, X3

	// scramble 3 times
	AESENC	X2, X2
	AESENC	X3, X3
	AESENC	X2, X2
	AESENC	X3, X3
	AESENC	X2, X2
	AESENC	X3, X3

	// combine results
	PXOR	X3, X2
	MOVQ	X2, AX	// return X2
	RET

aes33to64:
	// make 3 more starting seeds
	MOVO	X1, X2
	MOVO	X1, X3
	PXOR	runtime·aeskeysched+16(SB), X1
	PXOR	runtime·aeskeysched+32(SB), X2
	PXOR	runtime·aeskeysched+48(SB), X3
	AESENC	X1, X1
	AESENC	X2, X2
	AESENC	X3, X3

	MOVOU	(AX), X4
	MOVOU	16(AX), X5
	MOVOU	-32(AX)(CX*1), X6
	MOVOU	-16(AX)(CX*1), X7

	PXOR	X0, X4
	PXOR	X1, X5
	PXOR	X2, X6
	PXOR	X3, X7

	AESENC	X4, X4
	AESENC	X5, X5
	AESENC	X6, X6
	AESENC	X7, X7

	AESENC	X4, X4
	AESENC	X5, X5
	AESENC	X6, X6
	AESENC	X7, X7

	AESENC	X4, X4
	AESENC	X5, X5
	AESENC	X6, X6
	AESENC	X7, X7

	PXOR	X6, X4
	PXOR	X7, X5
	PXOR	X5, X4
	MOVQ	X4, AX	// return X4
	RET

aes65to128:
	// make 7 more starting seeds
	MOVO	X1, X2
	MOVO	X1, X3
	MOVO	X1, X4
	MOVO	X1, X5
	MOVO	X1, X6
	MOVO	X1, X7
	PXOR	runtime·aeskeysched+16(SB), X1
	PXOR	runtime·aeskeysched+32(SB), X2
	PXOR	runtime·aeskeysched+48(SB), X3
	PXOR	runtime·aeskeysched+64(SB), X4
	PXOR	runtime·aeskeysched+80(SB), X5
	PXOR	runtime·aeskeysched+96(SB), X6
	PXOR	runtime·aeskeysched+112(SB), X7
	AESENC	X1, X1
	AESENC	X2, X2
	AESENC	X3, X3
	AESENC	X4, X4
	AESENC	X5, X5
	AESENC	X6, X6
	AESENC	X7, X7

	// load data
	MOVOU	(AX), X8
	MOVOU	16(AX), X9
	MOVOU	32(AX), X10
	MOVOU	48(AX), X11
	MOVOU	-64(AX)(CX*1), X12
	MOVOU	-48(AX)(CX*1), X13
	MOVOU	-32(AX)(CX*1), X14
	MOVOU	-16(AX)(CX*1), X15

	// xor with seed
	PXOR	X0, X8
	PXOR	X1, X9
	PXOR	X2, X10
	PXOR	X3, X11
	PXOR	X4, X12
	PXOR	X5, X13
	PXOR	X6, X14
	PXOR	X7, X15

	// scramble 3 times
	AESENC	X8, X8
	AESENC	X9, X9
	AESENC	X10, X10
	AESENC	X11, X11
	AESENC	X12, X12
	AESENC	X13, X13
	AESENC	X14, X14
	AESENC	X15, X15

	AESENC	X8, X8
	AESENC	X9, X9
	AESENC	X10, X10
	AESENC	X11, X11
	AESENC	X12, X12
	AESENC	X13, X13
	AESENC	X14, X14
	AESENC	X15, X15

	AESENC	X8, X8
	AESENC	X9, X9
	AESENC	X10, X10
	AESENC	X11, X11
	AESENC	X12, X12
	AESENC	X13, X13
	AESENC	X14, X14
	AESENC	X15, X15

	// combine results
	PXOR	X12, X8
	PXOR	X13, X9
	PXOR	X14, X10
	PXOR	X15, X11
	PXOR	X10, X8
	PXOR	X11, X9
	PXOR	X9, X8
	// X15 must be zero on return
	PXOR	X15, X15
	MOVQ	X8, AX	// return X8
	RET

aes129plus:
	// make 7 more starting seeds
	MOVO	X1, X2
	MOVO	X1, X3
	MOVO	X1, X4
	MOVO	X1, X5
	MOVO	X1, X6
	MOVO	X1, X7
	PXOR	runtime·aeskeysched+16(SB), X1
	PXOR	runtime·aeskeysched+32(SB), X2
	PXOR	runtime·aeskeysched+48(SB), X3
	PXOR	runtime·aeskeysched+64(SB), X4
	PXOR	runtime·aeskeysched+80(SB), X5
	PXOR	runtime·aeskeysched+96(SB), X6
	PXOR	runtime·aeskeysched+112(SB), X7
	AESENC	X1, X1
	AESENC	X2, X2
	AESENC	X3, X3
	AESENC	X4, X4
	AESENC	X5, X5
	AESENC	X6, X6
	AESENC	X7, X7

	// start with last (possibly overlapping) block
	MOVOU	-128(AX)(CX*1), X8
	MOVOU	-112(AX)(CX*1), X9
	MOVOU	-96(AX)(CX*1), X10
	MOVOU	-80(AX)(CX*1), X11
	MOVOU	-64(AX)(CX*1), X12
	MOVOU	-48(AX)(CX*1), X13
	MOVOU	-32(AX)(CX*1), X14
	MOVOU	-16(AX)(CX*1), X15

	// xor in seed
	PXOR	X0, X8
	PXOR	X1, X9
	PXOR	X2, X10
	PXOR	X3, X11
	PXOR	X4, X12
	PXOR	X5, X13
	PXOR	X6, X14
	PXOR	X7, X15

	// compute number of remaining 128-byte blocks
	DECQ	CX
	SHRQ	$7, CX

aesloop:
	// scramble state
	AESENC	X8, X8
	AESENC	X9, X9
	AESENC	X10, X10
	AESENC	X11, X11
	AESENC	X12, X12
	AESENC	X13, X13
	AESENC	X14, X14
	AESENC	X15, X15

	// scramble state, xor in a block
	MOVOU	(AX), X0
	MOVOU	16(AX), X1
	MOVOU	32(AX), X2
	MOVOU	48(AX), X3
	AESENC	X0, X8
	AESENC	X1, X9
	AESENC	X2, X10
	AESENC	X3, X11
	MOVOU	64(AX), X4
	MOVOU	80(AX), X5
	MOVOU	96(AX), X6
	MOVOU	112(AX), X7
	AESENC	X4, X12
	AESENC	X5, X13
	AESENC	X6, X14
	AESENC	X7, X15

	ADDQ	$128, AX
	DECQ	CX
	JNE	aesloop

	// 3 more scrambles to finish
	AESENC	X8, X8
	AESENC	X9, X9
	AESENC	X10, X10
	AESENC	X11, X11
	AESENC	X12, X12
	AESENC	X13, X13
	AESENC	X14, X14
	AESENC	X15, X15
	AESENC	X8, X8
	AESENC	X9, X9
	AESENC	X10, X10
	AESENC	X11, X11
	AESENC	X12, X12
	AESENC	X13, X13
	AESENC	X14, X14
	AESENC	X15, X15
	AESENC	X8, X8
	AESENC	X9, X9
	AESENC	X10, X10
	AESENC	X11, X11
	AESENC	X12, X12
	AESENC	X13, X13
	AESENC	X14, X14
	AESENC	X15, X15

	PXOR	X12, X8
	PXOR	X13, X9
	PXOR	X14, X10
	PXOR	X15, X11
	PXOR	X10, X8
	PXOR	X11, X9
	PXOR	X9, X8
	// X15 must be zero on return
	PXOR	X15, X15
	MOVQ	X8, AX	// return X8
	RET

// func memhash32(p unsafe.Pointer, h uintptr) uintptr
// ABIInternal for performance.
TEXT runtime·memhash32<ABIInternal>(SB),NOSPLIT,$0-24
	// AX = ptr to data
	// BX = seed
	CMPB	runtime·useAeshash(SB), $0
	JEQ	noaes
	MOVQ	BX, X0	// X0 = seed
	PINSRD	$2, (AX), X0	// data
	AESENC	runtime·aeskeysched+0(SB), X0
	AESENC	runtime·aeskeysched+16(SB), X0
	AESENC	runtime·aeskeysched+32(SB), X0
	MOVQ	X0, AX	// return X0
	RET
noaes:
	JMP	runtime·memhash32Fallback<ABIInternal>(SB)

// func memhash64(p unsafe.Pointer, h uintptr) uintptr
// ABIInternal for performance.
TEXT runtime·memhash64<ABIInternal>(SB),NOSPLIT,$0-24
	// AX = ptr to data
	// BX = seed
	CMPB	runtime·useAeshash(SB), $0
	JEQ	noaes
	MOVQ	BX, X0	// X0 = seed
	PINSRQ	$1, (AX), X0	// data
	AESENC	runtime·aeskeysched+0(SB), X0
	AESENC	runtime·aeskeysched+16(SB), X0
	AESENC	runtime·aeskeysched+32(SB), X0
	MOVQ	X0, AX	// return X0
	RET
noaes:
	JMP	runtime·memhash64Fallback<ABIInternal>(SB)

// simple mask to get rid of data in the high part of the register.
DATA masks<>+0x00(SB)/8, $0x0000000000000000
DATA masks<>+0x08(SB)/8, $0x0000000000000000
DATA masks<>+0x10(SB)/8, $0x00000000000000ff
DATA masks<>+0x18(SB)/8, $0x0000000000000000
DATA masks<>+0x20(SB)/8, $0x000000000000ffff
DATA masks<>+0x28(SB)/8, $0x0000000000000000
DATA masks<>+0x30(SB)/8, $0x0000000000ffffff
DATA masks<>+0x38(SB)/8, $0x0000000000000000
DATA masks<>+0x40(SB)/8, $0x00000000ffffffff
DATA masks<>+0x48(SB)/8, $0x0000000000000000
DATA masks<>+0x50(SB)/8, $0x000000ffffffffff
DATA masks<>+0x58(SB)/8, $0x0000000000000000
DATA masks<>+0x60(SB)/8, $0x0000ffffffffffff
DATA masks<>+0x68(SB)/8, $0x0000000000000000
DATA masks<>+0x70(SB)/8, $0x00ffffffffffffff
DATA masks<>+0x78(SB)/8, $0x0000000000000000
DATA masks<>+0x80(SB)/8, $0xffffffffffffffff
DATA masks<>+0x88(SB)/8, $0x0000000000000000
DATA masks<>+0x90(SB)/8, $0xffffffffffffffff
DATA masks<>+0x98(SB)/8, $0x00000000000000ff
DATA masks<>+0xa0(SB)/8, $0xffffffffffffffff
DATA masks<>+0xa8(SB)/8, $0x000000000000ffff
DATA masks<>+0xb0(SB)/8, $0xffffffffffffffff
DATA masks<>+0xb8(SB)/8, $0x0000000000ffffff
DATA masks<>+0xc0(SB)/8, $0xffffffffffffffff
DATA masks<>+0xc8(SB)/8, $0x00000000ffffffff
DATA masks<>+0xd0(SB)/8, $0xffffffffffffffff
DATA masks<>+0xd8(SB)/8, $0x000000ffffffffff
DATA masks<>+0xe0(SB)/8, $0xffffffffffffffff
DATA masks<>+0xe8(SB)/8, $0x0000ffffffffffff
DATA masks<>+0xf0(SB)/8, $0xffffffffffffffff
DATA masks<>+0xf8(SB)/8, $0x00ffffffffffffff
GLOBL masks<>(SB),RODATA,$256

// func checkASM() bool
TEXT ·checkASM(SB),NOSPLIT,$0-1
	// check that masks<>(SB) and shifts<>(SB) are aligned to 16-byte
	MOVQ	$masks<>(SB), AX
	MOVQ	$shifts<>(SB), BX
	ORQ	BX, AX
	TESTQ	$15, AX
	SETEQ	ret+0(FP)
	RET

// these are arguments to pshufb. They move data down from
// the high bytes of the register to the low bytes of the register.
// index is how many bytes to move.
DATA shifts<>+0x00(SB)/8, $0x0000000000000000
DATA shifts<>+0x08(SB)/8, $0x0000000000000000
DATA shifts<>+0x10(SB)/8, $0xffffffffffffff0f
DATA shifts<>+0x18(SB)/8, $0xffffffffffffffff
DATA shifts<>+0x20(SB)/8, $0xffffffffffff0f0e
DATA shifts<>+0x28(SB)/8, $0xffffffffffffffff
DATA shifts<>+0x30(SB)/8, $0xffffffffff0f0e0d
DATA shifts<>+0x38(SB)/8, $0xffffffffffffffff
DATA shifts<>+0x40(SB)/8, $0xffffffff0f0e0d0c
DATA shifts<>+0x48(SB)/8, $0xffffffffffffffff
DATA shifts<>+0x50(SB)/8, $0xffffff0f0e0d0c0b
DATA shifts<>+0x58(SB)/8, $0xffffffffffffffff
DATA shifts<>+0x60(SB)/8, $0xffff0f0e0d0c0b0a
DATA shifts<>+0x68(SB)/8, $0xffffffffffffffff
DATA shifts<>+0x70(SB)/8, $0xff0f0e0d0c0b0a09
DATA shifts<>+0x78(SB)/8, $0xffffffffffffffff
DATA shifts<>+0x80(SB)/8, $0x0f0e0d0c0b0a0908
DATA shifts<>+0x88(SB)/8, $0xffffffffffffffff
DATA shifts<>+0x90(SB)/8, $0x0e0d0c0b0a090807
DATA shifts<>+0x98(SB)/8, $0xffffffffffffff0f
DATA shifts<>+0xa0(SB)/8, $0x0d0c0b0a09080706
DATA shifts<>+0xa8(SB)/8, $0xffffffffffff0f0e
DATA shifts<>+0xb0(SB)/8, $0x0c0b0a0908070605
DATA shifts<>+0xb8(SB)/8, $0xffffffffff0f0e0d
DATA shifts<>+0xc0(SB)/8, $0x0b0a090807060504
DATA shifts<>+0xc8(SB)/8, $0xffffffff0f0e0d0c
DATA shifts<>+0xd0(SB)/8, $0x0a09080706050403
DATA shifts<>+0xd8(SB)/8, $0xffffff0f0e0d0c0b
DATA shifts<>+0xe0(SB)/8, $0x0908070605040302
DATA shifts<>+0xe8(SB)/8, $0xffff0f0e0d0c0b0a
DATA shifts<>+0xf0(SB)/8, $0x0807060504030201
DATA shifts<>+0xf8(SB)/8, $0xff0f0e0d0c0b0a09
GLOBL shifts<>(SB),RODATA,$256

TEXT runtime·return0(SB), NOSPLIT, $0
	MOVL	$0, AX
	RET


// Called from cgo wrappers, this function returns g->m->curg.stack.hi.
// Must obey the gcc calling convention.
TEXT _cgo_topofstack(SB),NOSPLIT,$0
	get_tls(CX)
	MOVQ	g(CX), AX
	MOVQ	g_m(AX), AX
	MOVQ	m_curg(AX), AX
	MOVQ	(g_stack+stack_hi)(AX), AX
	RET

// The top-most function running on a goroutine
// returns to goexit+PCQuantum.
TEXT runtime·goexit(SB),NOSPLIT|TOPFRAME,$0-0
	BYTE	$0x90	// NOP
	CALL	runtime·goexit1(SB)	// does not return
	// traceback from goexit1 must hit code range of goexit
	BYTE	$0x90	// NOP

// This is called from .init_array and follows the platform, not Go, ABI.
TEXT runtime·addmoduledata(SB),NOSPLIT,$0-0
	PUSHQ	R15 // The access to global variables below implicitly uses R15, which is callee-save
	MOVQ	runtime·lastmoduledatap(SB), AX
	MOVQ	DI, moduledata_next(AX)
	MOVQ	DI, runtime·lastmoduledatap(SB)
	POPQ	R15
	RET

// Initialize special registers then jump to sigpanic.
// This function is injected from the signal handler for panicking
// signals. It is quite painful to set X15 in the signal context,
// so we do it here.
TEXT ·sigpanic0(SB),NOSPLIT,$0-0
	get_tls(R14)
	MOVQ	g(R14), R14
#ifndef GOOS_plan9
	XORPS	X15, X15
#endif
	JMP	·sigpanic<ABIInternal>(SB)

// gcWriteBarrier performs a heap pointer write and informs the GC.
//
// gcWriteBarrier does NOT follow the Go ABI. It takes two arguments:
// - DI is the destination of the write
// - AX is the value being written at DI
// It clobbers FLAGS. It does not clobber any general-purpose registers,
// but may clobber others (e.g., SSE registers).
// Defined as ABIInternal since it does not use the stack-based Go ABI.
TEXT runtime·gcWriteBarrier<ABIInternal>(SB),NOSPLIT,$112
	// Save the registers clobbered by the fast path. This is slightly
	// faster than having the caller spill these.
	MOVQ	R12, 96(SP)
	MOVQ	R13, 104(SP)
	// TODO: Consider passing g.m.p in as an argument so they can be shared
	// across a sequence of write barriers.
	MOVQ	g_m(R14), R13
	MOVQ	m_p(R13), R13
	MOVQ	(p_wbBuf+wbBuf_next)(R13), R12
	// Increment wbBuf.next position.
	LEAQ	16(R12), R12
	MOVQ	R12, (p_wbBuf+wbBuf_next)(R13)
	CMPQ	R12, (p_wbBuf+wbBuf_end)(R13)
	// Record the write.
	MOVQ	AX, -16(R12)	// Record value
	// Note: This turns bad pointer writes into bad
	// pointer reads, which could be confusing. We could avoid
	// reading from obviously bad pointers, which would
	// take care of the vast majority of these. We could
	// patch this up in the signal handler, or use XCHG to
	// combine the read and the write.
	MOVQ	(DI), R13
	MOVQ	R13, -8(R12)	// Record *slot
	// Is the buffer full? (flags set in CMPQ above)
	JEQ	flush
ret:
	MOVQ	96(SP), R12
	MOVQ	104(SP), R13
	// Do the write.
	MOVQ	AX, (DI)
	RET

flush:
	// Save all general purpose registers since these could be
	// clobbered by wbBufFlush and were not saved by the caller.
	// It is possible for wbBufFlush to clobber other registers
	// (e.g., SSE registers), but the compiler takes care of saving
	// those in the caller if necessary. This strikes a balance
	// with registers that are likely to be used.
	//
	// We don't have type information for these, but all code under
	// here is NOSPLIT, so nothing will observe these.
	//
	// TODO: We could strike a different balance; e.g., saving X0
	// and not saving GP registers that are less likely to be used.
	MOVQ	DI, 0(SP)	// Also first argument to wbBufFlush
	MOVQ	AX, 8(SP)	// Also second argument to wbBufFlush
	MOVQ	BX, 16(SP)
	MOVQ	CX, 24(SP)
	MOVQ	DX, 32(SP)
	// DI already saved
	MOVQ	SI, 40(SP)
	MOVQ	BP, 48(SP)
	MOVQ	R8, 56(SP)
	MOVQ	R9, 64(SP)
	MOVQ	R10, 72(SP)
	MOVQ	R11, 80(SP)
	// R12 already saved
	// R13 already saved
	// R14 is g
	MOVQ	R15, 88(SP)

	// This takes arguments DI and AX
	CALL	runtime·wbBufFlush(SB)

	MOVQ	0(SP), DI
	MOVQ	8(SP), AX
	MOVQ	16(SP), BX
	MOVQ	24(SP), CX
	MOVQ	32(SP), DX
	MOVQ	40(SP), SI
	MOVQ	48(SP), BP
	MOVQ	56(SP), R8
	MOVQ	64(SP), R9
	MOVQ	72(SP), R10
	MOVQ	80(SP), R11
	MOVQ	88(SP), R15
	JMP	ret

// gcWriteBarrierCX is gcWriteBarrier, but with args in DI and CX.
// Defined as ABIInternal since it does not use the stable Go ABI.
TEXT runtime·gcWriteBarrierCX<ABIInternal>(SB),NOSPLIT,$0
	XCHGQ CX, AX
	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
	XCHGQ CX, AX
	RET

// gcWriteBarrierDX is gcWriteBarrier, but with args in DI and DX.
// Defined as ABIInternal since it does not use the stable Go ABI.
TEXT runtime·gcWriteBarrierDX<ABIInternal>(SB),NOSPLIT,$0
	XCHGQ DX, AX
	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
	XCHGQ DX, AX
	RET

// gcWriteBarrierBX is gcWriteBarrier, but with args in DI and BX.
// Defined as ABIInternal since it does not use the stable Go ABI.
TEXT runtime·gcWriteBarrierBX<ABIInternal>(SB),NOSPLIT,$0
	XCHGQ BX, AX
	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
	XCHGQ BX, AX
	RET

// gcWriteBarrierBP is gcWriteBarrier, but with args in DI and BP.
// Defined as ABIInternal since it does not use the stable Go ABI.
TEXT runtime·gcWriteBarrierBP<ABIInternal>(SB),NOSPLIT,$0
	XCHGQ BP, AX
	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
	XCHGQ BP, AX
	RET

// gcWriteBarrierSI is gcWriteBarrier, but with args in DI and SI.
// Defined as ABIInternal since it does not use the stable Go ABI.
TEXT runtime·gcWriteBarrierSI<ABIInternal>(SB),NOSPLIT,$0
	XCHGQ SI, AX
	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
	XCHGQ SI, AX
	RET

// gcWriteBarrierR8 is gcWriteBarrier, but with args in DI and R8.
// Defined as ABIInternal since it does not use the stable Go ABI.
TEXT runtime·gcWriteBarrierR8<ABIInternal>(SB),NOSPLIT,$0
	XCHGQ R8, AX
	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
	XCHGQ R8, AX
	RET

// gcWriteBarrierR9 is gcWriteBarrier, but with args in DI and R9.
// Defined as ABIInternal since it does not use the stable Go ABI.
TEXT runtime·gcWriteBarrierR9<ABIInternal>(SB),NOSPLIT,$0
	XCHGQ R9, AX
	CALL runtime·gcWriteBarrier<ABIInternal>(SB)
	XCHGQ R9, AX
	RET

DATA	debugCallFrameTooLarge<>+0x00(SB)/20, $"call frame too large"
GLOBL	debugCallFrameTooLarge<>(SB), RODATA, $20	// Size duplicated below

// debugCallV2 is the entry point for debugger-injected function
// calls on running goroutines. It informs the runtime that a
// debug call has been injected and creates a call frame for the
// debugger to fill in.
//
// To inject a function call, a debugger should:
// 1. Check that the goroutine is in state _Grunning and that
//    there are at least 256 bytes free on the stack.
// 2. Push the current PC on the stack (updating SP).
// 3. Write the desired argument frame size at SP-16 (using the SP
//    after step 2).
// 4. Save all machine registers (including flags and XMM registers)
//    so they can be restored later by the debugger.
// 5. Set the PC to debugCallV2 and resume execution.
//
// If the goroutine is in state _Grunnable, then it's not generally
// safe to inject a call because it may return out via other runtime
// operations. Instead, the debugger should unwind the stack to find
// the return to non-runtime code, add a temporary breakpoint there,
// and inject the call once that breakpoint is hit.
//
// If the goroutine is in any other state, it's not safe to inject a call.
//
// This function communicates back to the debugger by setting R12 and
// invoking INT3 to raise a breakpoint signal. See the comments in the
// implementation for the protocol the debugger is expected to
// follow. InjectDebugCall in the runtime tests demonstrates this protocol.
//
// The debugger must ensure that any pointers passed to the function
// obey escape analysis requirements. Specifically, it must not pass
// a stack pointer to an escaping argument. debugCallV2 cannot check
// this invariant.
//
// This is ABIInternal because Go code injects its PC directly into new
// goroutine stacks.
TEXT runtime·debugCallV2<ABIInternal>(SB),NOSPLIT,$152-0
	// Save all registers that may contain pointers so they can be
	// conservatively scanned.
	//
	// We can't do anything that might clobber any of these
	// registers before this.
	MOVQ	R15, r15-(14*8+8)(SP)
	MOVQ	R14, r14-(13*8+8)(SP)
	MOVQ	R13, r13-(12*8+8)(SP)
	MOVQ	R12, r12-(11*8+8)(SP)
	MOVQ	R11, r11-(10*8+8)(SP)
	MOVQ	R10, r10-(9*8+8)(SP)
	MOVQ	R9, r9-(8*8+8)(SP)
	MOVQ	R8, r8-(7*8+8)(SP)
	MOVQ	DI, di-(6*8+8)(SP)
	MOVQ	SI, si-(5*8+8)(SP)
	MOVQ	BP, bp-(4*8+8)(SP)
	MOVQ	BX, bx-(3*8+8)(SP)
	MOVQ	DX, dx-(2*8+8)(SP)
	// Save the frame size before we clobber it. Either of the last
	// saves could clobber this depending on whether there's a saved BP.
	MOVQ	frameSize-24(FP), DX	// aka -16(RSP) before prologue
	MOVQ	CX, cx-(1*8+8)(SP)
	MOVQ	AX, ax-(0*8+8)(SP)

	// Save the argument frame size.
	MOVQ	DX, frameSize-128(SP)

	// Perform a safe-point check.
	MOVQ	retpc-8(FP), AX	// Caller's PC
	MOVQ	AX, 0(SP)
	CALL	runtime·debugCallCheck(SB)
	MOVQ	8(SP), AX
	TESTQ	AX, AX
	JZ	good
	// The safety check failed. Put the reason string at the top
	// of the stack.
	MOVQ	AX, 0(SP)
	MOVQ	16(SP), AX
	MOVQ	AX, 8(SP)
	// Set R12 to 8 and invoke INT3. The debugger should get the
	// reason a call can't be injected from the top of the stack
	// and resume execution.
	MOVQ	$8, R12
	BYTE	$0xcc
	JMP	restore

good:
	// Registers are saved and it's safe to make a call.
	// Open up a call frame, moving the stack if necessary.
	//
	// Once the frame is allocated, this will set R12 to 0 and
	// invoke INT3. The debugger should write the argument
	// frame for the call at SP, set up argument registers, push
	// the trapping PC on the stack, set the PC to the function to
	// call, set RDX to point to the closure (if a closure call),
	// and resume execution.
	//
	// If the function returns, this will set R12 to 1 and invoke
	// INT3. The debugger can then inspect any return value saved
	// on the stack at SP and in registers and resume execution again.
	//
	// If the function panics, this will set R12 to 2 and invoke INT3.
	// The interface{} value of the panic will be at SP. The debugger
	// can inspect the panic value and resume execution again.
#define DEBUG_CALL_DISPATCH(NAME,MAXSIZE)	\
	CMPQ	AX, $MAXSIZE;			\
	JA	5(PC);				\
	MOVQ	$NAME(SB), AX;			\
	MOVQ	AX, 0(SP);			\
	CALL	runtime·debugCallWrap(SB);	\
	JMP	restore

	MOVQ	frameSize-128(SP), AX
	DEBUG_CALL_DISPATCH(debugCall32<>, 32)
	DEBUG_CALL_DISPATCH(debugCall64<>, 64)
	DEBUG_CALL_DISPATCH(debugCall128<>, 128)
	DEBUG_CALL_DISPATCH(debugCall256<>, 256)
	DEBUG_CALL_DISPATCH(debugCall512<>, 512)
	DEBUG_CALL_DISPATCH(debugCall1024<>, 1024)
	DEBUG_CALL_DISPATCH(debugCall2048<>, 2048)
	DEBUG_CALL_DISPATCH(debugCall4096<>, 4096)
	DEBUG_CALL_DISPATCH(debugCall8192<>, 8192)
	DEBUG_CALL_DISPATCH(debugCall16384<>, 16384)
	DEBUG_CALL_DISPATCH(debugCall32768<>, 32768)
	DEBUG_CALL_DISPATCH(debugCall65536<>, 65536)
	// The frame size is too large. Report the error.
	MOVQ	$debugCallFrameTooLarge<>(SB), AX
	MOVQ	AX, 0(SP)
	MOVQ	$20, 8(SP) // length of debugCallFrameTooLarge string
	MOVQ	$8, R12
	BYTE	$0xcc
	JMP	restore

restore:
	// Calls and failures resume here.
	//
	// Set R12 to 16 and invoke INT3. The debugger should restore
	// all registers except RIP and RSP and resume execution.
	MOVQ	$16, R12
	BYTE	$0xcc
	// We must not modify flags after this point.

	// Restore pointer-containing registers, which may have been
	// modified from the debugger's copy by stack copying.
	MOVQ	ax-(0*8+8)(SP), AX
	MOVQ	cx-(1*8+8)(SP), CX
	MOVQ	dx-(2*8+8)(SP), DX
	MOVQ	bx-(3*8+8)(SP), BX
	MOVQ	bp-(4*8+8)(SP), BP
	MOVQ	si-(5*8+8)(SP), SI
	MOVQ	di-(6*8+8)(SP), DI
	MOVQ	r8-(7*8+8)(SP), R8
	MOVQ	r9-(8*8+8)(SP), R9
	MOVQ	r10-(9*8+8)(SP), R10
	MOVQ	r11-(10*8+8)(SP), R11
	MOVQ	r12-(11*8+8)(SP), R12
	MOVQ	r13-(12*8+8)(SP), R13
	MOVQ	r14-(13*8+8)(SP), R14
	MOVQ	r15-(14*8+8)(SP), R15

	RET

// runtime.debugCallCheck assumes that functions defined with the
// DEBUG_CALL_FN macro are safe points to inject calls.
#define DEBUG_CALL_FN(NAME,MAXSIZE)		\
TEXT NAME(SB),WRAPPER,$MAXSIZE-0;		\
	NO_LOCAL_POINTERS;			\
	MOVQ	$0, R12;				\
	BYTE	$0xcc;				\
	MOVQ	$1, R12;				\
	BYTE	$0xcc;				\
	RET
DEBUG_CALL_FN(debugCall32<>, 32)
DEBUG_CALL_FN(debugCall64<>, 64)
DEBUG_CALL_FN(debugCall128<>, 128)
DEBUG_CALL_FN(debugCall256<>, 256)
DEBUG_CALL_FN(debugCall512<>, 512)
DEBUG_CALL_FN(debugCall1024<>, 1024)
DEBUG_CALL_FN(debugCall2048<>, 2048)
DEBUG_CALL_FN(debugCall4096<>, 4096)
DEBUG_CALL_FN(debugCall8192<>, 8192)
DEBUG_CALL_FN(debugCall16384<>, 16384)
DEBUG_CALL_FN(debugCall32768<>, 32768)
DEBUG_CALL_FN(debugCall65536<>, 65536)

// func debugCallPanicked(val interface{})
TEXT runtime·debugCallPanicked(SB),NOSPLIT,$16-16
	// Copy the panic value to the top of stack.
	MOVQ	val_type+0(FP), AX
	MOVQ	AX, 0(SP)
	MOVQ	val_data+8(FP), AX
	MOVQ	AX, 8(SP)
	MOVQ	$2, R12
	BYTE	$0xcc
	RET

// Note: these functions use a special calling convention to save generated code space.
// Arguments are passed in registers, but the space for those arguments are allocated
// in the caller's stack frame. These stubs write the args into that stack space and
// then tail call to the corresponding runtime handler.
// The tail call makes these stubs disappear in backtraces.
// Defined as ABIInternal since they do not use the stack-based Go ABI.
TEXT runtime·panicIndex<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	CX, BX
	JMP	runtime·goPanicIndex<ABIInternal>(SB)
TEXT runtime·panicIndexU<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	CX, BX
	JMP	runtime·goPanicIndexU<ABIInternal>(SB)
TEXT runtime·panicSliceAlen<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	CX, AX
	MOVQ	DX, BX
	JMP	runtime·goPanicSliceAlen<ABIInternal>(SB)
TEXT runtime·panicSliceAlenU<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	CX, AX
	MOVQ	DX, BX
	JMP	runtime·goPanicSliceAlenU<ABIInternal>(SB)
TEXT runtime·panicSliceAcap<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	CX, AX
	MOVQ	DX, BX
	JMP	runtime·goPanicSliceAcap<ABIInternal>(SB)
TEXT runtime·panicSliceAcapU<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	CX, AX
	MOVQ	DX, BX
	JMP	runtime·goPanicSliceAcapU<ABIInternal>(SB)
TEXT runtime·panicSliceB<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	CX, BX
	JMP	runtime·goPanicSliceB<ABIInternal>(SB)
TEXT runtime·panicSliceBU<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	CX, BX
	JMP	runtime·goPanicSliceBU<ABIInternal>(SB)
TEXT runtime·panicSlice3Alen<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	DX, AX
	JMP	runtime·goPanicSlice3Alen<ABIInternal>(SB)
TEXT runtime·panicSlice3AlenU<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	DX, AX
	JMP	runtime·goPanicSlice3AlenU<ABIInternal>(SB)
TEXT runtime·panicSlice3Acap<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	DX, AX
	JMP	runtime·goPanicSlice3Acap<ABIInternal>(SB)
TEXT runtime·panicSlice3AcapU<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	DX, AX
	JMP	runtime·goPanicSlice3AcapU<ABIInternal>(SB)
TEXT runtime·panicSlice3B<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	CX, AX
	MOVQ	DX, BX
	JMP	runtime·goPanicSlice3B<ABIInternal>(SB)
TEXT runtime·panicSlice3BU<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	CX, AX
	MOVQ	DX, BX
	JMP	runtime·goPanicSlice3BU<ABIInternal>(SB)
TEXT runtime·panicSlice3C<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	CX, BX
	JMP	runtime·goPanicSlice3C<ABIInternal>(SB)
TEXT runtime·panicSlice3CU<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	CX, BX
	JMP	runtime·goPanicSlice3CU<ABIInternal>(SB)
TEXT runtime·panicSliceConvert<ABIInternal>(SB),NOSPLIT,$0-16
	MOVQ	DX, AX
	JMP	runtime·goPanicSliceConvert<ABIInternal>(SB)

#ifdef GOOS_android
// Use the free TLS_SLOT_APP slot #2 on Android Q.
// Earlier androids are set up in gcc_android.c.
DATA runtime·tls_g+0(SB)/8, $16
GLOBL runtime·tls_g+0(SB), NOPTR, $8
#endif

// The compiler and assembler's -spectre=ret mode rewrites
// all indirect CALL AX / JMP AX instructions to be
// CALL retpolineAX / JMP retpolineAX.
// See https://support.google.com/faqs/answer/7625886.
#define RETPOLINE(reg) \
	/*   CALL setup */     BYTE $0xE8; BYTE $(2+2); BYTE $0; BYTE $0; BYTE $0;	\
	/* nospec: */									\
	/*   PAUSE */           BYTE $0xF3; BYTE $0x90;					\
	/*   JMP nospec */      BYTE $0xEB; BYTE $-(2+2);				\
	/* setup: */									\
	/*   MOVQ AX, 0(SP) */  BYTE $0x48|((reg&8)>>1); BYTE $0x89;			\
	                        BYTE $0x04|((reg&7)<<3); BYTE $0x24;			\
	/*   RET */             BYTE $0xC3

TEXT runtime·retpolineAX(SB),NOSPLIT,$0; RETPOLINE(0)
TEXT runtime·retpolineCX(SB),NOSPLIT,$0; RETPOLINE(1)
TEXT runtime·retpolineDX(SB),NOSPLIT,$0; RETPOLINE(2)
TEXT runtime·retpolineBX(SB),NOSPLIT,$0; RETPOLINE(3)
/* SP is 4, can't happen / magic encodings */
TEXT runtime·retpolineBP(SB),NOSPLIT,$0; RETPOLINE(5)
TEXT runtime·retpolineSI(SB),NOSPLIT,$0; RETPOLINE(6)
TEXT runtime·retpolineDI(SB),NOSPLIT,$0; RETPOLINE(7)
TEXT runtime·retpolineR8(SB),NOSPLIT,$0; RETPOLINE(8)
TEXT runtime·retpolineR9(SB),NOSPLIT,$0; RETPOLINE(9)
TEXT runtime·retpolineR10(SB),NOSPLIT,$0; RETPOLINE(10)
TEXT runtime·retpolineR11(SB),NOSPLIT,$0; RETPOLINE(11)
TEXT runtime·retpolineR12(SB),NOSPLIT,$0; RETPOLINE(12)
TEXT runtime·retpolineR13(SB),NOSPLIT,$0; RETPOLINE(13)
TEXT runtime·retpolineR14(SB),NOSPLIT,$0; RETPOLINE(14)
TEXT runtime·retpolineR15(SB),NOSPLIT,$0; RETPOLINE(15)