Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

   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
//===-- MSP430ISelLowering.cpp - MSP430 DAG Lowering Implementation  ------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the MSP430TargetLowering class.
//
//===----------------------------------------------------------------------===//

#include "MSP430ISelLowering.h"
#include "MSP430.h"
#include "MSP430MachineFunctionInfo.h"
#include "MSP430Subtarget.h"
#include "MSP430TargetMachine.h"
#include "llvm/CodeGen/CallingConvLower.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/SelectionDAGISel.h"
#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
#include "llvm/CodeGen/ValueTypes.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GlobalAlias.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;

#define DEBUG_TYPE "msp430-lower"

MSP430TargetLowering::MSP430TargetLowering(const TargetMachine &TM,
                                           const MSP430Subtarget &STI)
    : TargetLowering(TM) {

  // Set up the register classes.
  addRegisterClass(MVT::i8,  &MSP430::GR8RegClass);
  addRegisterClass(MVT::i16, &MSP430::GR16RegClass);

  // Compute derived properties from the register classes
  computeRegisterProperties(STI.getRegisterInfo());

  // Provide all sorts of operation actions
  setStackPointerRegisterToSaveRestore(MSP430::SP);
  setBooleanContents(ZeroOrOneBooleanContent);
  setBooleanVectorContents(ZeroOrOneBooleanContent); // FIXME: Is this correct?

  // We have post-incremented loads / stores.
  setIndexedLoadAction(ISD::POST_INC, MVT::i8, Legal);
  setIndexedLoadAction(ISD::POST_INC, MVT::i16, Legal);

  for (MVT VT : MVT::integer_valuetypes()) {
    setLoadExtAction(ISD::EXTLOAD,  VT, MVT::i1,  Promote);
    setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i1,  Promote);
    setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i1,  Promote);
    setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i8,  Expand);
    setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i16, Expand);
  }

  // We don't have any truncstores
  setTruncStoreAction(MVT::i16, MVT::i8, Expand);

  setOperationAction(ISD::SRA,              MVT::i8,    Custom);
  setOperationAction(ISD::SHL,              MVT::i8,    Custom);
  setOperationAction(ISD::SRL,              MVT::i8,    Custom);
  setOperationAction(ISD::SRA,              MVT::i16,   Custom);
  setOperationAction(ISD::SHL,              MVT::i16,   Custom);
  setOperationAction(ISD::SRL,              MVT::i16,   Custom);
  setOperationAction(ISD::ROTL,             MVT::i8,    Expand);
  setOperationAction(ISD::ROTR,             MVT::i8,    Expand);
  setOperationAction(ISD::ROTL,             MVT::i16,   Expand);
  setOperationAction(ISD::ROTR,             MVT::i16,   Expand);
  setOperationAction(ISD::GlobalAddress,    MVT::i16,   Custom);
  setOperationAction(ISD::ExternalSymbol,   MVT::i16,   Custom);
  setOperationAction(ISD::BlockAddress,     MVT::i16,   Custom);
  setOperationAction(ISD::BR_JT,            MVT::Other, Expand);
  setOperationAction(ISD::BR_CC,            MVT::i8,    Custom);
  setOperationAction(ISD::BR_CC,            MVT::i16,   Custom);
  setOperationAction(ISD::BRCOND,           MVT::Other, Expand);
  setOperationAction(ISD::SETCC,            MVT::i8,    Custom);
  setOperationAction(ISD::SETCC,            MVT::i16,   Custom);
  setOperationAction(ISD::SELECT,           MVT::i8,    Expand);
  setOperationAction(ISD::SELECT,           MVT::i16,   Expand);
  setOperationAction(ISD::SELECT_CC,        MVT::i8,    Custom);
  setOperationAction(ISD::SELECT_CC,        MVT::i16,   Custom);
  setOperationAction(ISD::SIGN_EXTEND,      MVT::i16,   Custom);
  setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i8, Expand);
  setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i16, Expand);
  setOperationAction(ISD::STACKSAVE,        MVT::Other, Expand);
  setOperationAction(ISD::STACKRESTORE,     MVT::Other, Expand);

  setOperationAction(ISD::CTTZ,             MVT::i8,    Expand);
  setOperationAction(ISD::CTTZ,             MVT::i16,   Expand);
  setOperationAction(ISD::CTLZ,             MVT::i8,    Expand);
  setOperationAction(ISD::CTLZ,             MVT::i16,   Expand);
  setOperationAction(ISD::CTPOP,            MVT::i8,    Expand);
  setOperationAction(ISD::CTPOP,            MVT::i16,   Expand);

  setOperationAction(ISD::SHL_PARTS,        MVT::i8,    Expand);
  setOperationAction(ISD::SHL_PARTS,        MVT::i16,   Expand);
  setOperationAction(ISD::SRL_PARTS,        MVT::i8,    Expand);
  setOperationAction(ISD::SRL_PARTS,        MVT::i16,   Expand);
  setOperationAction(ISD::SRA_PARTS,        MVT::i8,    Expand);
  setOperationAction(ISD::SRA_PARTS,        MVT::i16,   Expand);

  setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1,   Expand);

  // FIXME: Implement efficiently multiplication by a constant
  setOperationAction(ISD::MUL,              MVT::i8,    Promote);
  setOperationAction(ISD::MULHS,            MVT::i8,    Promote);
  setOperationAction(ISD::MULHU,            MVT::i8,    Promote);
  setOperationAction(ISD::SMUL_LOHI,        MVT::i8,    Promote);
  setOperationAction(ISD::UMUL_LOHI,        MVT::i8,    Promote);
  setOperationAction(ISD::MUL,              MVT::i16,   LibCall);
  setOperationAction(ISD::MULHS,            MVT::i16,   Expand);
  setOperationAction(ISD::MULHU,            MVT::i16,   Expand);
  setOperationAction(ISD::SMUL_LOHI,        MVT::i16,   Expand);
  setOperationAction(ISD::UMUL_LOHI,        MVT::i16,   Expand);

  setOperationAction(ISD::UDIV,             MVT::i8,    Promote);
  setOperationAction(ISD::UDIVREM,          MVT::i8,    Promote);
  setOperationAction(ISD::UREM,             MVT::i8,    Promote);
  setOperationAction(ISD::SDIV,             MVT::i8,    Promote);
  setOperationAction(ISD::SDIVREM,          MVT::i8,    Promote);
  setOperationAction(ISD::SREM,             MVT::i8,    Promote);
  setOperationAction(ISD::UDIV,             MVT::i16,   LibCall);
  setOperationAction(ISD::UDIVREM,          MVT::i16,   Expand);
  setOperationAction(ISD::UREM,             MVT::i16,   LibCall);
  setOperationAction(ISD::SDIV,             MVT::i16,   LibCall);
  setOperationAction(ISD::SDIVREM,          MVT::i16,   Expand);
  setOperationAction(ISD::SREM,             MVT::i16,   LibCall);

  // varargs support
  setOperationAction(ISD::VASTART,          MVT::Other, Custom);
  setOperationAction(ISD::VAARG,            MVT::Other, Expand);
  setOperationAction(ISD::VAEND,            MVT::Other, Expand);
  setOperationAction(ISD::VACOPY,           MVT::Other, Expand);
  setOperationAction(ISD::JumpTable,        MVT::i16,   Custom);

  // EABI Libcalls - EABI Section 6.2
  const struct {
    const RTLIB::Libcall Op;
    const char * const Name;
    const ISD::CondCode Cond;
  } LibraryCalls[] = {
    // Floating point conversions - EABI Table 6
    { RTLIB::FPROUND_F64_F32,   "__mspabi_cvtdf",   ISD::SETCC_INVALID },
    { RTLIB::FPEXT_F32_F64,     "__mspabi_cvtfd",   ISD::SETCC_INVALID },
    // The following is NOT implemented in libgcc
    //{ RTLIB::FPTOSINT_F64_I16,  "__mspabi_fixdi", ISD::SETCC_INVALID },
    { RTLIB::FPTOSINT_F64_I32,  "__mspabi_fixdli",  ISD::SETCC_INVALID },
    { RTLIB::FPTOSINT_F64_I64,  "__mspabi_fixdlli", ISD::SETCC_INVALID },
    // The following is NOT implemented in libgcc
    //{ RTLIB::FPTOUINT_F64_I16,  "__mspabi_fixdu", ISD::SETCC_INVALID },
    { RTLIB::FPTOUINT_F64_I32,  "__mspabi_fixdul",  ISD::SETCC_INVALID },
    { RTLIB::FPTOUINT_F64_I64,  "__mspabi_fixdull", ISD::SETCC_INVALID },
    // The following is NOT implemented in libgcc
    //{ RTLIB::FPTOSINT_F32_I16,  "__mspabi_fixfi", ISD::SETCC_INVALID },
    { RTLIB::FPTOSINT_F32_I32,  "__mspabi_fixfli",  ISD::SETCC_INVALID },
    { RTLIB::FPTOSINT_F32_I64,  "__mspabi_fixflli", ISD::SETCC_INVALID },
    // The following is NOT implemented in libgcc
    //{ RTLIB::FPTOUINT_F32_I16,  "__mspabi_fixfu", ISD::SETCC_INVALID },
    { RTLIB::FPTOUINT_F32_I32,  "__mspabi_fixful",  ISD::SETCC_INVALID },
    { RTLIB::FPTOUINT_F32_I64,  "__mspabi_fixfull", ISD::SETCC_INVALID },
    // TODO The following IS implemented in libgcc
    //{ RTLIB::SINTTOFP_I16_F64,  "__mspabi_fltid", ISD::SETCC_INVALID },
    { RTLIB::SINTTOFP_I32_F64,  "__mspabi_fltlid",  ISD::SETCC_INVALID },
    // TODO The following IS implemented in libgcc but is not in the EABI
    { RTLIB::SINTTOFP_I64_F64,  "__mspabi_fltllid", ISD::SETCC_INVALID },
    // TODO The following IS implemented in libgcc
    //{ RTLIB::UINTTOFP_I16_F64,  "__mspabi_fltud", ISD::SETCC_INVALID },
    { RTLIB::UINTTOFP_I32_F64,  "__mspabi_fltuld",  ISD::SETCC_INVALID },
    // The following IS implemented in libgcc but is not in the EABI
    { RTLIB::UINTTOFP_I64_F64,  "__mspabi_fltulld", ISD::SETCC_INVALID },
    // TODO The following IS implemented in libgcc
    //{ RTLIB::SINTTOFP_I16_F32,  "__mspabi_fltif", ISD::SETCC_INVALID },
    { RTLIB::SINTTOFP_I32_F32,  "__mspabi_fltlif",  ISD::SETCC_INVALID },
    // TODO The following IS implemented in libgcc but is not in the EABI
    { RTLIB::SINTTOFP_I64_F32,  "__mspabi_fltllif", ISD::SETCC_INVALID },
    // TODO The following IS implemented in libgcc
    //{ RTLIB::UINTTOFP_I16_F32,  "__mspabi_fltuf", ISD::SETCC_INVALID },
    { RTLIB::UINTTOFP_I32_F32,  "__mspabi_fltulf",  ISD::SETCC_INVALID },
    // The following IS implemented in libgcc but is not in the EABI
    { RTLIB::UINTTOFP_I64_F32,  "__mspabi_fltullf", ISD::SETCC_INVALID },

    // Floating point comparisons - EABI Table 7
    { RTLIB::OEQ_F64, "__mspabi_cmpd", ISD::SETEQ },
    { RTLIB::UNE_F64, "__mspabi_cmpd", ISD::SETNE },
    { RTLIB::OGE_F64, "__mspabi_cmpd", ISD::SETGE },
    { RTLIB::OLT_F64, "__mspabi_cmpd", ISD::SETLT },
    { RTLIB::OLE_F64, "__mspabi_cmpd", ISD::SETLE },
    { RTLIB::OGT_F64, "__mspabi_cmpd", ISD::SETGT },
    { RTLIB::OEQ_F32, "__mspabi_cmpf", ISD::SETEQ },
    { RTLIB::UNE_F32, "__mspabi_cmpf", ISD::SETNE },
    { RTLIB::OGE_F32, "__mspabi_cmpf", ISD::SETGE },
    { RTLIB::OLT_F32, "__mspabi_cmpf", ISD::SETLT },
    { RTLIB::OLE_F32, "__mspabi_cmpf", ISD::SETLE },
    { RTLIB::OGT_F32, "__mspabi_cmpf", ISD::SETGT },

    // Floating point arithmetic - EABI Table 8
    { RTLIB::ADD_F64,  "__mspabi_addd", ISD::SETCC_INVALID },
    { RTLIB::ADD_F32,  "__mspabi_addf", ISD::SETCC_INVALID },
    { RTLIB::DIV_F64,  "__mspabi_divd", ISD::SETCC_INVALID },
    { RTLIB::DIV_F32,  "__mspabi_divf", ISD::SETCC_INVALID },
    { RTLIB::MUL_F64,  "__mspabi_mpyd", ISD::SETCC_INVALID },
    { RTLIB::MUL_F32,  "__mspabi_mpyf", ISD::SETCC_INVALID },
    { RTLIB::SUB_F64,  "__mspabi_subd", ISD::SETCC_INVALID },
    { RTLIB::SUB_F32,  "__mspabi_subf", ISD::SETCC_INVALID },
    // The following are NOT implemented in libgcc
    // { RTLIB::NEG_F64,  "__mspabi_negd", ISD::SETCC_INVALID },
    // { RTLIB::NEG_F32,  "__mspabi_negf", ISD::SETCC_INVALID },

    // Universal Integer Operations - EABI Table 9
    { RTLIB::SDIV_I16,   "__mspabi_divi", ISD::SETCC_INVALID },
    { RTLIB::SDIV_I32,   "__mspabi_divli", ISD::SETCC_INVALID },
    { RTLIB::SDIV_I64,   "__mspabi_divlli", ISD::SETCC_INVALID },
    { RTLIB::UDIV_I16,   "__mspabi_divu", ISD::SETCC_INVALID },
    { RTLIB::UDIV_I32,   "__mspabi_divul", ISD::SETCC_INVALID },
    { RTLIB::UDIV_I64,   "__mspabi_divull", ISD::SETCC_INVALID },
    { RTLIB::SREM_I16,   "__mspabi_remi", ISD::SETCC_INVALID },
    { RTLIB::SREM_I32,   "__mspabi_remli", ISD::SETCC_INVALID },
    { RTLIB::SREM_I64,   "__mspabi_remlli", ISD::SETCC_INVALID },
    { RTLIB::UREM_I16,   "__mspabi_remu", ISD::SETCC_INVALID },
    { RTLIB::UREM_I32,   "__mspabi_remul", ISD::SETCC_INVALID },
    { RTLIB::UREM_I64,   "__mspabi_remull", ISD::SETCC_INVALID },

    // Bitwise Operations - EABI Table 10
    // TODO: __mspabi_[srli/srai/slli] ARE implemented in libgcc
    { RTLIB::SRL_I32,    "__mspabi_srll", ISD::SETCC_INVALID },
    { RTLIB::SRA_I32,    "__mspabi_sral", ISD::SETCC_INVALID },
    { RTLIB::SHL_I32,    "__mspabi_slll", ISD::SETCC_INVALID },
    // __mspabi_[srlll/srall/sllll/rlli/rlll] are NOT implemented in libgcc

  };

  for (const auto &LC : LibraryCalls) {
    setLibcallName(LC.Op, LC.Name);
    if (LC.Cond != ISD::SETCC_INVALID)
      setCmpLibcallCC(LC.Op, LC.Cond);
  }

  if (STI.hasHWMult16()) {
    const struct {
      const RTLIB::Libcall Op;
      const char * const Name;
    } LibraryCalls[] = {
      // Integer Multiply - EABI Table 9
      { RTLIB::MUL_I16,   "__mspabi_mpyi_hw" },
      { RTLIB::MUL_I32,   "__mspabi_mpyl_hw" },
      { RTLIB::MUL_I64,   "__mspabi_mpyll_hw" },
      // TODO The __mspabi_mpysl*_hw functions ARE implemented in libgcc
      // TODO The __mspabi_mpyul*_hw functions ARE implemented in libgcc
    };
    for (const auto &LC : LibraryCalls) {
      setLibcallName(LC.Op, LC.Name);
    }
  } else if (STI.hasHWMult32()) {
    const struct {
      const RTLIB::Libcall Op;
      const char * const Name;
    } LibraryCalls[] = {
      // Integer Multiply - EABI Table 9
      { RTLIB::MUL_I16,   "__mspabi_mpyi_hw" },
      { RTLIB::MUL_I32,   "__mspabi_mpyl_hw32" },
      { RTLIB::MUL_I64,   "__mspabi_mpyll_hw32" },
      // TODO The __mspabi_mpysl*_hw32 functions ARE implemented in libgcc
      // TODO The __mspabi_mpyul*_hw32 functions ARE implemented in libgcc
    };
    for (const auto &LC : LibraryCalls) {
      setLibcallName(LC.Op, LC.Name);
    }
  } else if (STI.hasHWMultF5()) {
    const struct {
      const RTLIB::Libcall Op;
      const char * const Name;
    } LibraryCalls[] = {
      // Integer Multiply - EABI Table 9
      { RTLIB::MUL_I16,   "__mspabi_mpyi_f5hw" },
      { RTLIB::MUL_I32,   "__mspabi_mpyl_f5hw" },
      { RTLIB::MUL_I64,   "__mspabi_mpyll_f5hw" },
      // TODO The __mspabi_mpysl*_f5hw functions ARE implemented in libgcc
      // TODO The __mspabi_mpyul*_f5hw functions ARE implemented in libgcc
    };
    for (const auto &LC : LibraryCalls) {
      setLibcallName(LC.Op, LC.Name);
    }
  } else { // NoHWMult
    const struct {
      const RTLIB::Libcall Op;
      const char * const Name;
    } LibraryCalls[] = {
      // Integer Multiply - EABI Table 9
      { RTLIB::MUL_I16,   "__mspabi_mpyi" },
      { RTLIB::MUL_I32,   "__mspabi_mpyl" },
      { RTLIB::MUL_I64,   "__mspabi_mpyll" },
      // The __mspabi_mpysl* functions are NOT implemented in libgcc
      // The __mspabi_mpyul* functions are NOT implemented in libgcc
    };
    for (const auto &LC : LibraryCalls) {
      setLibcallName(LC.Op, LC.Name);
    }
    setLibcallCallingConv(RTLIB::MUL_I64, CallingConv::MSP430_BUILTIN);
  }

  // Several of the runtime library functions use a special calling conv
  setLibcallCallingConv(RTLIB::UDIV_I64, CallingConv::MSP430_BUILTIN);
  setLibcallCallingConv(RTLIB::UREM_I64, CallingConv::MSP430_BUILTIN);
  setLibcallCallingConv(RTLIB::SDIV_I64, CallingConv::MSP430_BUILTIN);
  setLibcallCallingConv(RTLIB::SREM_I64, CallingConv::MSP430_BUILTIN);
  setLibcallCallingConv(RTLIB::ADD_F64, CallingConv::MSP430_BUILTIN);
  setLibcallCallingConv(RTLIB::SUB_F64, CallingConv::MSP430_BUILTIN);
  setLibcallCallingConv(RTLIB::MUL_F64, CallingConv::MSP430_BUILTIN);
  setLibcallCallingConv(RTLIB::DIV_F64, CallingConv::MSP430_BUILTIN);
  setLibcallCallingConv(RTLIB::OEQ_F64, CallingConv::MSP430_BUILTIN);
  setLibcallCallingConv(RTLIB::UNE_F64, CallingConv::MSP430_BUILTIN);
  setLibcallCallingConv(RTLIB::OGE_F64, CallingConv::MSP430_BUILTIN);
  setLibcallCallingConv(RTLIB::OLT_F64, CallingConv::MSP430_BUILTIN);
  setLibcallCallingConv(RTLIB::OLE_F64, CallingConv::MSP430_BUILTIN);
  setLibcallCallingConv(RTLIB::OGT_F64, CallingConv::MSP430_BUILTIN);
  // TODO: __mspabi_srall, __mspabi_srlll, __mspabi_sllll

  setMinFunctionAlignment(1);
  setPrefFunctionAlignment(1);
}

SDValue MSP430TargetLowering::LowerOperation(SDValue Op,
                                             SelectionDAG &DAG) const {
  switch (Op.getOpcode()) {
  case ISD::SHL: // FALLTHROUGH
  case ISD::SRL:
  case ISD::SRA:              return LowerShifts(Op, DAG);
  case ISD::GlobalAddress:    return LowerGlobalAddress(Op, DAG);
  case ISD::BlockAddress:     return LowerBlockAddress(Op, DAG);
  case ISD::ExternalSymbol:   return LowerExternalSymbol(Op, DAG);
  case ISD::SETCC:            return LowerSETCC(Op, DAG);
  case ISD::BR_CC:            return LowerBR_CC(Op, DAG);
  case ISD::SELECT_CC:        return LowerSELECT_CC(Op, DAG);
  case ISD::SIGN_EXTEND:      return LowerSIGN_EXTEND(Op, DAG);
  case ISD::RETURNADDR:       return LowerRETURNADDR(Op, DAG);
  case ISD::FRAMEADDR:        return LowerFRAMEADDR(Op, DAG);
  case ISD::VASTART:          return LowerVASTART(Op, DAG);
  case ISD::JumpTable:        return LowerJumpTable(Op, DAG);
  default:
    llvm_unreachable("unimplemented operand");
  }
}

//===----------------------------------------------------------------------===//
//                       MSP430 Inline Assembly Support
//===----------------------------------------------------------------------===//

/// getConstraintType - Given a constraint letter, return the type of
/// constraint it is for this target.
TargetLowering::ConstraintType
MSP430TargetLowering::getConstraintType(StringRef Constraint) const {
  if (Constraint.size() == 1) {
    switch (Constraint[0]) {
    case 'r':
      return C_RegisterClass;
    default:
      break;
    }
  }
  return TargetLowering::getConstraintType(Constraint);
}

std::pair<unsigned, const TargetRegisterClass *>
MSP430TargetLowering::getRegForInlineAsmConstraint(
    const TargetRegisterInfo *TRI, StringRef Constraint, MVT VT) const {
  if (Constraint.size() == 1) {
    // GCC Constraint Letters
    switch (Constraint[0]) {
    default: break;
    case 'r':   // GENERAL_REGS
      if (VT == MVT::i8)
        return std::make_pair(0U, &MSP430::GR8RegClass);

      return std::make_pair(0U, &MSP430::GR16RegClass);
    }
  }

  return TargetLowering::getRegForInlineAsmConstraint(TRI, Constraint, VT);
}

//===----------------------------------------------------------------------===//
//                      Calling Convention Implementation
//===----------------------------------------------------------------------===//

#include "MSP430GenCallingConv.inc"

/// For each argument in a function store the number of pieces it is composed
/// of.
template<typename ArgT>
static void ParseFunctionArgs(const SmallVectorImpl<ArgT> &Args,
                              SmallVectorImpl<unsigned> &Out) {
  unsigned CurrentArgIndex;

  if (Args.empty())
    return;

  CurrentArgIndex = Args[0].OrigArgIndex;
  Out.push_back(0);

  for (auto &Arg : Args) {
    if (CurrentArgIndex == Arg.OrigArgIndex) {
      Out.back() += 1;
    } else {
      Out.push_back(1);
      CurrentArgIndex = Arg.OrigArgIndex;
    }
  }
}

static void AnalyzeVarArgs(CCState &State,
                           const SmallVectorImpl<ISD::OutputArg> &Outs) {
  State.AnalyzeCallOperands(Outs, CC_MSP430_AssignStack);
}

static void AnalyzeVarArgs(CCState &State,
                           const SmallVectorImpl<ISD::InputArg> &Ins) {
  State.AnalyzeFormalArguments(Ins, CC_MSP430_AssignStack);
}

/// Analyze incoming and outgoing function arguments. We need custom C++ code
/// to handle special constraints in the ABI like reversing the order of the
/// pieces of splitted arguments. In addition, all pieces of a certain argument
/// have to be passed either using registers or the stack but never mixing both.
template<typename ArgT>
static void AnalyzeArguments(CCState &State,
                             SmallVectorImpl<CCValAssign> &ArgLocs,
                             const SmallVectorImpl<ArgT> &Args) {
  static const MCPhysReg CRegList[] = {
    MSP430::R12, MSP430::R13, MSP430::R14, MSP430::R15
  };
  static const unsigned CNbRegs = array_lengthof(CRegList);
  static const MCPhysReg BuiltinRegList[] = {
    MSP430::R8, MSP430::R9, MSP430::R10, MSP430::R11,
    MSP430::R12, MSP430::R13, MSP430::R14, MSP430::R15
  };
  static const unsigned BuiltinNbRegs = array_lengthof(BuiltinRegList);

  ArrayRef<MCPhysReg> RegList;
  unsigned NbRegs;

  bool Builtin = (State.getCallingConv() == CallingConv::MSP430_BUILTIN);
  if (Builtin) {
    RegList = BuiltinRegList;
    NbRegs = BuiltinNbRegs;
  } else {
    RegList = CRegList;
    NbRegs = CNbRegs;
  }

  if (State.isVarArg()) {
    AnalyzeVarArgs(State, Args);
    return;
  }

  SmallVector<unsigned, 4> ArgsParts;
  ParseFunctionArgs(Args, ArgsParts);

  if (Builtin) {
    assert(ArgsParts.size() == 2 &&
        "Builtin calling convention requires two arguments");
  }

  unsigned RegsLeft = NbRegs;
  bool UsedStack = false;
  unsigned ValNo = 0;

  for (unsigned i = 0, e = ArgsParts.size(); i != e; i++) {
    MVT ArgVT = Args[ValNo].VT;
    ISD::ArgFlagsTy ArgFlags = Args[ValNo].Flags;
    MVT LocVT = ArgVT;
    CCValAssign::LocInfo LocInfo = CCValAssign::Full;

    // Promote i8 to i16
    if (LocVT == MVT::i8) {
      LocVT = MVT::i16;
      if (ArgFlags.isSExt())
          LocInfo = CCValAssign::SExt;
      else if (ArgFlags.isZExt())
          LocInfo = CCValAssign::ZExt;
      else
          LocInfo = CCValAssign::AExt;
    }

    // Handle byval arguments
    if (ArgFlags.isByVal()) {
      State.HandleByVal(ValNo++, ArgVT, LocVT, LocInfo, 2, 2, ArgFlags);
      continue;
    }

    unsigned Parts = ArgsParts[i];

    if (Builtin) {
      assert(Parts == 4 &&
          "Builtin calling convention requires 64-bit arguments");
    }

    if (!UsedStack && Parts == 2 && RegsLeft == 1) {
      // Special case for 32-bit register split, see EABI section 3.3.3
      unsigned Reg = State.AllocateReg(RegList);
      State.addLoc(CCValAssign::getReg(ValNo++, ArgVT, Reg, LocVT, LocInfo));
      RegsLeft -= 1;

      UsedStack = true;
      CC_MSP430_AssignStack(ValNo++, ArgVT, LocVT, LocInfo, ArgFlags, State);
    } else if (Parts <= RegsLeft) {
      for (unsigned j = 0; j < Parts; j++) {
        unsigned Reg = State.AllocateReg(RegList);
        State.addLoc(CCValAssign::getReg(ValNo++, ArgVT, Reg, LocVT, LocInfo));
        RegsLeft--;
      }
    } else {
      UsedStack = true;
      for (unsigned j = 0; j < Parts; j++)
        CC_MSP430_AssignStack(ValNo++, ArgVT, LocVT, LocInfo, ArgFlags, State);
    }
  }
}

static void AnalyzeRetResult(CCState &State,
                             const SmallVectorImpl<ISD::InputArg> &Ins) {
  State.AnalyzeCallResult(Ins, RetCC_MSP430);
}

static void AnalyzeRetResult(CCState &State,
                             const SmallVectorImpl<ISD::OutputArg> &Outs) {
  State.AnalyzeReturn(Outs, RetCC_MSP430);
}

template<typename ArgT>
static void AnalyzeReturnValues(CCState &State,
                                SmallVectorImpl<CCValAssign> &RVLocs,
                                const SmallVectorImpl<ArgT> &Args) {
  AnalyzeRetResult(State, Args);
}

SDValue MSP430TargetLowering::LowerFormalArguments(
    SDValue Chain, CallingConv::ID CallConv, bool isVarArg,
    const SmallVectorImpl<ISD::InputArg> &Ins, const SDLoc &dl,
    SelectionDAG &DAG, SmallVectorImpl<SDValue> &InVals) const {

  switch (CallConv) {
  default:
    report_fatal_error("Unsupported calling convention");
  case CallingConv::C:
  case CallingConv::Fast:
    return LowerCCCArguments(Chain, CallConv, isVarArg, Ins, dl, DAG, InVals);
  case CallingConv::MSP430_INTR:
    if (Ins.empty())
      return Chain;
    report_fatal_error("ISRs cannot have arguments");
  }
}

SDValue
MSP430TargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
                                SmallVectorImpl<SDValue> &InVals) const {
  SelectionDAG &DAG                     = CLI.DAG;
  SDLoc &dl                             = CLI.DL;
  SmallVectorImpl<ISD::OutputArg> &Outs = CLI.Outs;
  SmallVectorImpl<SDValue> &OutVals     = CLI.OutVals;
  SmallVectorImpl<ISD::InputArg> &Ins   = CLI.Ins;
  SDValue Chain                         = CLI.Chain;
  SDValue Callee                        = CLI.Callee;
  bool &isTailCall                      = CLI.IsTailCall;
  CallingConv::ID CallConv              = CLI.CallConv;
  bool isVarArg                         = CLI.IsVarArg;

  // MSP430 target does not yet support tail call optimization.
  isTailCall = false;

  switch (CallConv) {
  default:
    report_fatal_error("Unsupported calling convention");
  case CallingConv::MSP430_BUILTIN:
  case CallingConv::Fast:
  case CallingConv::C:
    return LowerCCCCallTo(Chain, Callee, CallConv, isVarArg, isTailCall,
                          Outs, OutVals, Ins, dl, DAG, InVals);
  case CallingConv::MSP430_INTR:
    report_fatal_error("ISRs cannot be called directly");
  }
}

/// LowerCCCArguments - transform physical registers into virtual registers and
/// generate load operations for arguments places on the stack.
// FIXME: struct return stuff
SDValue MSP430TargetLowering::LowerCCCArguments(
    SDValue Chain, CallingConv::ID CallConv, bool isVarArg,
    const SmallVectorImpl<ISD::InputArg> &Ins, const SDLoc &dl,
    SelectionDAG &DAG, SmallVectorImpl<SDValue> &InVals) const {
  MachineFunction &MF = DAG.getMachineFunction();
  MachineFrameInfo &MFI = MF.getFrameInfo();
  MachineRegisterInfo &RegInfo = MF.getRegInfo();
  MSP430MachineFunctionInfo *FuncInfo = MF.getInfo<MSP430MachineFunctionInfo>();

  // Assign locations to all of the incoming arguments.
  SmallVector<CCValAssign, 16> ArgLocs;
  CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(), ArgLocs,
                 *DAG.getContext());
  AnalyzeArguments(CCInfo, ArgLocs, Ins);

  // Create frame index for the start of the first vararg value
  if (isVarArg) {
    unsigned Offset = CCInfo.getNextStackOffset();
    FuncInfo->setVarArgsFrameIndex(MFI.CreateFixedObject(1, Offset, true));
  }

  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
    CCValAssign &VA = ArgLocs[i];
    if (VA.isRegLoc()) {
      // Arguments passed in registers
      EVT RegVT = VA.getLocVT();
      switch (RegVT.getSimpleVT().SimpleTy) {
      default:
        {
#ifndef NDEBUG
          errs() << "LowerFormalArguments Unhandled argument type: "
               << RegVT.getEVTString() << "\n";
#endif
          llvm_unreachable(nullptr);
        }
      case MVT::i16:
        unsigned VReg = RegInfo.createVirtualRegister(&MSP430::GR16RegClass);
        RegInfo.addLiveIn(VA.getLocReg(), VReg);
        SDValue ArgValue = DAG.getCopyFromReg(Chain, dl, VReg, RegVT);

        // If this is an 8-bit value, it is really passed promoted to 16
        // bits. Insert an assert[sz]ext to capture this, then truncate to the
        // right size.
        if (VA.getLocInfo() == CCValAssign::SExt)
          ArgValue = DAG.getNode(ISD::AssertSext, dl, RegVT, ArgValue,
                                 DAG.getValueType(VA.getValVT()));
        else if (VA.getLocInfo() == CCValAssign::ZExt)
          ArgValue = DAG.getNode(ISD::AssertZext, dl, RegVT, ArgValue,
                                 DAG.getValueType(VA.getValVT()));

        if (VA.getLocInfo() != CCValAssign::Full)
          ArgValue = DAG.getNode(ISD::TRUNCATE, dl, VA.getValVT(), ArgValue);

        InVals.push_back(ArgValue);
      }
    } else {
      // Sanity check
      assert(VA.isMemLoc());

      SDValue InVal;
      ISD::ArgFlagsTy Flags = Ins[i].Flags;

      if (Flags.isByVal()) {
        int FI = MFI.CreateFixedObject(Flags.getByValSize(),
                                       VA.getLocMemOffset(), true);
        InVal = DAG.getFrameIndex(FI, getPointerTy(DAG.getDataLayout()));
      } else {
        // Load the argument to a virtual register
        unsigned ObjSize = VA.getLocVT().getSizeInBits()/8;
        if (ObjSize > 2) {
            errs() << "LowerFormalArguments Unhandled argument type: "
                << EVT(VA.getLocVT()).getEVTString()
                << "\n";
        }
        // Create the frame index object for this incoming parameter...
        int FI = MFI.CreateFixedObject(ObjSize, VA.getLocMemOffset(), true);

        // Create the SelectionDAG nodes corresponding to a load
        //from this parameter
        SDValue FIN = DAG.getFrameIndex(FI, MVT::i16);
        InVal = DAG.getLoad(
            VA.getLocVT(), dl, Chain, FIN,
            MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), FI));
      }

      InVals.push_back(InVal);
    }
  }

  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
    if (Ins[i].Flags.isSRet()) {
      unsigned Reg = FuncInfo->getSRetReturnReg();
      if (!Reg) {
        Reg = MF.getRegInfo().createVirtualRegister(
            getRegClassFor(MVT::i16));
        FuncInfo->setSRetReturnReg(Reg);
      }
      SDValue Copy = DAG.getCopyToReg(DAG.getEntryNode(), dl, Reg, InVals[i]);
      Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Copy, Chain);
    }
  }

  return Chain;
}

bool
MSP430TargetLowering::CanLowerReturn(CallingConv::ID CallConv,
                                     MachineFunction &MF,
                                     bool IsVarArg,
                                     const SmallVectorImpl<ISD::OutputArg> &Outs,
                                     LLVMContext &Context) const {
  SmallVector<CCValAssign, 16> RVLocs;
  CCState CCInfo(CallConv, IsVarArg, MF, RVLocs, Context);
  return CCInfo.CheckReturn(Outs, RetCC_MSP430);
}

SDValue
MSP430TargetLowering::LowerReturn(SDValue Chain, CallingConv::ID CallConv,
                                  bool isVarArg,
                                  const SmallVectorImpl<ISD::OutputArg> &Outs,
                                  const SmallVectorImpl<SDValue> &OutVals,
                                  const SDLoc &dl, SelectionDAG &DAG) const {

  MachineFunction &MF = DAG.getMachineFunction();

  // CCValAssign - represent the assignment of the return value to a location
  SmallVector<CCValAssign, 16> RVLocs;

  // ISRs cannot return any value.
  if (CallConv == CallingConv::MSP430_INTR && !Outs.empty())
    report_fatal_error("ISRs cannot return any value");

  // CCState - Info about the registers and stack slot.
  CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(), RVLocs,
                 *DAG.getContext());

  // Analize return values.
  AnalyzeReturnValues(CCInfo, RVLocs, Outs);

  SDValue Flag;
  SmallVector<SDValue, 4> RetOps(1, Chain);

  // Copy the result values into the output registers.
  for (unsigned i = 0; i != RVLocs.size(); ++i) {
    CCValAssign &VA = RVLocs[i];
    assert(VA.isRegLoc() && "Can only return in registers!");

    Chain = DAG.getCopyToReg(Chain, dl, VA.getLocReg(),
                             OutVals[i], Flag);

    // Guarantee that all emitted copies are stuck together,
    // avoiding something bad.
    Flag = Chain.getValue(1);
    RetOps.push_back(DAG.getRegister(VA.getLocReg(), VA.getLocVT()));
  }

  if (MF.getFunction().hasStructRetAttr()) {
    MSP430MachineFunctionInfo *FuncInfo = MF.getInfo<MSP430MachineFunctionInfo>();
    unsigned Reg = FuncInfo->getSRetReturnReg();

    if (!Reg)
      llvm_unreachable("sret virtual register not created in entry block");

    SDValue Val =
      DAG.getCopyFromReg(Chain, dl, Reg, getPointerTy(DAG.getDataLayout()));
    unsigned R12 = MSP430::R12;

    Chain = DAG.getCopyToReg(Chain, dl, R12, Val, Flag);
    Flag = Chain.getValue(1);
    RetOps.push_back(DAG.getRegister(R12, getPointerTy(DAG.getDataLayout())));
  }

  unsigned Opc = (CallConv == CallingConv::MSP430_INTR ?
                  MSP430ISD::RETI_FLAG : MSP430ISD::RET_FLAG);

  RetOps[0] = Chain;  // Update chain.

  // Add the flag if we have it.
  if (Flag.getNode())
    RetOps.push_back(Flag);

  return DAG.getNode(Opc, dl, MVT::Other, RetOps);
}

/// LowerCCCCallTo - functions arguments are copied from virtual regs to
/// (physical regs)/(stack frame), CALLSEQ_START and CALLSEQ_END are emitted.
SDValue MSP430TargetLowering::LowerCCCCallTo(
    SDValue Chain, SDValue Callee, CallingConv::ID CallConv, bool isVarArg,
    bool isTailCall, const SmallVectorImpl<ISD::OutputArg> &Outs,
    const SmallVectorImpl<SDValue> &OutVals,
    const SmallVectorImpl<ISD::InputArg> &Ins, const SDLoc &dl,
    SelectionDAG &DAG, SmallVectorImpl<SDValue> &InVals) const {
  // Analyze operands of the call, assigning locations to each operand.
  SmallVector<CCValAssign, 16> ArgLocs;
  CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(), ArgLocs,
                 *DAG.getContext());
  AnalyzeArguments(CCInfo, ArgLocs, Outs);

  // Get a count of how many bytes are to be pushed on the stack.
  unsigned NumBytes = CCInfo.getNextStackOffset();
  auto PtrVT = getPointerTy(DAG.getDataLayout());

  Chain = DAG.getCALLSEQ_START(Chain, NumBytes, 0, dl);

  SmallVector<std::pair<unsigned, SDValue>, 4> RegsToPass;
  SmallVector<SDValue, 12> MemOpChains;
  SDValue StackPtr;

  // Walk the register/memloc assignments, inserting copies/loads.
  for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
    CCValAssign &VA = ArgLocs[i];

    SDValue Arg = OutVals[i];

    // Promote the value if needed.
    switch (VA.getLocInfo()) {
      default: llvm_unreachable("Unknown loc info!");
      case CCValAssign::Full: break;
      case CCValAssign::SExt:
        Arg = DAG.getNode(ISD::SIGN_EXTEND, dl, VA.getLocVT(), Arg);
        break;
      case CCValAssign::ZExt:
        Arg = DAG.getNode(ISD::ZERO_EXTEND, dl, VA.getLocVT(), Arg);
        break;
      case CCValAssign::AExt:
        Arg = DAG.getNode(ISD::ANY_EXTEND, dl, VA.getLocVT(), Arg);
        break;
    }

    // Arguments that can be passed on register must be kept at RegsToPass
    // vector
    if (VA.isRegLoc()) {
      RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
    } else {
      assert(VA.isMemLoc());

      if (!StackPtr.getNode())
        StackPtr = DAG.getCopyFromReg(Chain, dl, MSP430::SP, PtrVT);

      SDValue PtrOff =
          DAG.getNode(ISD::ADD, dl, PtrVT, StackPtr,
                      DAG.getIntPtrConstant(VA.getLocMemOffset(), dl));

      SDValue MemOp;
      ISD::ArgFlagsTy Flags = Outs[i].Flags;

      if (Flags.isByVal()) {
        SDValue SizeNode = DAG.getConstant(Flags.getByValSize(), dl, MVT::i16);
        MemOp = DAG.getMemcpy(Chain, dl, PtrOff, Arg, SizeNode,
                              Flags.getByValAlign(),
                              /*isVolatile*/false,
                              /*AlwaysInline=*/true,
                              /*isTailCall=*/false,
                              MachinePointerInfo(),
                              MachinePointerInfo());
      } else {
        MemOp = DAG.getStore(Chain, dl, Arg, PtrOff, MachinePointerInfo());
      }

      MemOpChains.push_back(MemOp);
    }
  }

  // Transform all store nodes into one single node because all store nodes are
  // independent of each other.
  if (!MemOpChains.empty())
    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, MemOpChains);

  // Build a sequence of copy-to-reg nodes chained together with token chain and
  // flag operands which copy the outgoing args into registers.  The InFlag in
  // necessary since all emitted instructions must be stuck together.
  SDValue InFlag;
  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
    Chain = DAG.getCopyToReg(Chain, dl, RegsToPass[i].first,
                             RegsToPass[i].second, InFlag);
    InFlag = Chain.getValue(1);
  }

  // If the callee is a GlobalAddress node (quite common, every direct call is)
  // turn it into a TargetGlobalAddress node so that legalize doesn't hack it.
  // Likewise ExternalSymbol -> TargetExternalSymbol.
  if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
    Callee = DAG.getTargetGlobalAddress(G->getGlobal(), dl, MVT::i16);
  else if (ExternalSymbolSDNode *E = dyn_cast<ExternalSymbolSDNode>(Callee))
    Callee = DAG.getTargetExternalSymbol(E->getSymbol(), MVT::i16);

  // Returns a chain & a flag for retval copy to use.
  SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
  SmallVector<SDValue, 8> Ops;
  Ops.push_back(Chain);
  Ops.push_back(Callee);

  // Add argument registers to the end of the list so that they are
  // known live into the call.
  for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i)
    Ops.push_back(DAG.getRegister(RegsToPass[i].first,
                                  RegsToPass[i].second.getValueType()));

  if (InFlag.getNode())
    Ops.push_back(InFlag);

  Chain = DAG.getNode(MSP430ISD::CALL, dl, NodeTys, Ops);
  InFlag = Chain.getValue(1);

  // Create the CALLSEQ_END node.
  Chain = DAG.getCALLSEQ_END(Chain, DAG.getConstant(NumBytes, dl, PtrVT, true),
                             DAG.getConstant(0, dl, PtrVT, true), InFlag, dl);
  InFlag = Chain.getValue(1);

  // Handle result values, copying them out of physregs into vregs that we
  // return.
  return LowerCallResult(Chain, InFlag, CallConv, isVarArg, Ins, dl,
                         DAG, InVals);
}

/// LowerCallResult - Lower the result values of a call into the
/// appropriate copies out of appropriate physical registers.
///
SDValue MSP430TargetLowering::LowerCallResult(
    SDValue Chain, SDValue InFlag, CallingConv::ID CallConv, bool isVarArg,
    const SmallVectorImpl<ISD::InputArg> &Ins, const SDLoc &dl,
    SelectionDAG &DAG, SmallVectorImpl<SDValue> &InVals) const {

  // Assign locations to each value returned by this call.
  SmallVector<CCValAssign, 16> RVLocs;
  CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(), RVLocs,
                 *DAG.getContext());

  AnalyzeReturnValues(CCInfo, RVLocs, Ins);

  // Copy all of the result registers out of their specified physreg.
  for (unsigned i = 0; i != RVLocs.size(); ++i) {
    Chain = DAG.getCopyFromReg(Chain, dl, RVLocs[i].getLocReg(),
                               RVLocs[i].getValVT(), InFlag).getValue(1);
    InFlag = Chain.getValue(2);
    InVals.push_back(Chain.getValue(0));
  }

  return Chain;
}

SDValue MSP430TargetLowering::LowerShifts(SDValue Op,
                                          SelectionDAG &DAG) const {
  unsigned Opc = Op.getOpcode();
  SDNode* N = Op.getNode();
  EVT VT = Op.getValueType();
  SDLoc dl(N);

  // Expand non-constant shifts to loops:
  if (!isa<ConstantSDNode>(N->getOperand(1)))
    return Op;

  uint64_t ShiftAmount = cast<ConstantSDNode>(N->getOperand(1))->getZExtValue();

  // Expand the stuff into sequence of shifts.
  SDValue Victim = N->getOperand(0);

  if (ShiftAmount >= 8) {
    assert(VT == MVT::i16 && "Can not shift i8 by 8 and more");
    switch(Opc) {
    default:
      llvm_unreachable("Unknown shift");
    case ISD::SHL:
      // foo << (8 + N) => swpb(zext(foo)) << N
      Victim = DAG.getZeroExtendInReg(Victim, dl, MVT::i8);
      Victim = DAG.getNode(ISD::BSWAP, dl, VT, Victim);
      break;
    case ISD::SRA:
    case ISD::SRL:
      // foo >> (8 + N) => sxt(swpb(foo)) >> N
      Victim = DAG.getNode(ISD::BSWAP, dl, VT, Victim);
      Victim = (Opc == ISD::SRA)
                   ? DAG.getNode(ISD::SIGN_EXTEND_INREG, dl, VT, Victim,
                                 DAG.getValueType(MVT::i8))
                   : DAG.getZeroExtendInReg(Victim, dl, MVT::i8);
      break;
    }
    ShiftAmount -= 8;
  }

  if (Opc == ISD::SRL && ShiftAmount) {
    // Emit a special goodness here:
    // srl A, 1 => clrc; rrc A
    Victim = DAG.getNode(MSP430ISD::RRCL, dl, VT, Victim);
    ShiftAmount -= 1;
  }

  while (ShiftAmount--)
    Victim = DAG.getNode((Opc == ISD::SHL ? MSP430ISD::RLA : MSP430ISD::RRA),
                         dl, VT, Victim);

  return Victim;
}

SDValue MSP430TargetLowering::LowerGlobalAddress(SDValue Op,
                                                 SelectionDAG &DAG) const {
  const GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
  int64_t Offset = cast<GlobalAddressSDNode>(Op)->getOffset();
  auto PtrVT = getPointerTy(DAG.getDataLayout());

  // Create the TargetGlobalAddress node, folding in the constant offset.
  SDValue Result = DAG.getTargetGlobalAddress(GV, SDLoc(Op), PtrVT, Offset);
  return DAG.getNode(MSP430ISD::Wrapper, SDLoc(Op), PtrVT, Result);
}

SDValue MSP430TargetLowering::LowerExternalSymbol(SDValue Op,
                                                  SelectionDAG &DAG) const {
  SDLoc dl(Op);
  const char *Sym = cast<ExternalSymbolSDNode>(Op)->getSymbol();
  auto PtrVT = getPointerTy(DAG.getDataLayout());
  SDValue Result = DAG.getTargetExternalSymbol(Sym, PtrVT);

  return DAG.getNode(MSP430ISD::Wrapper, dl, PtrVT, Result);
}

SDValue MSP430TargetLowering::LowerBlockAddress(SDValue Op,
                                                SelectionDAG &DAG) const {
  SDLoc dl(Op);
  auto PtrVT = getPointerTy(DAG.getDataLayout());
  const BlockAddress *BA = cast<BlockAddressSDNode>(Op)->getBlockAddress();
  SDValue Result = DAG.getTargetBlockAddress(BA, PtrVT);

  return DAG.getNode(MSP430ISD::Wrapper, dl, PtrVT, Result);
}

static SDValue EmitCMP(SDValue &LHS, SDValue &RHS, SDValue &TargetCC,
                       ISD::CondCode CC, const SDLoc &dl, SelectionDAG &DAG) {
  // FIXME: Handle bittests someday
  assert(!LHS.getValueType().isFloatingPoint() && "We don't handle FP yet");

  // FIXME: Handle jump negative someday
  MSP430CC::CondCodes TCC = MSP430CC::COND_INVALID;
  switch (CC) {
  default: llvm_unreachable("Invalid integer condition!");
  case ISD::SETEQ:
    TCC = MSP430CC::COND_E;     // aka COND_Z
    // Minor optimization: if LHS is a constant, swap operands, then the
    // constant can be folded into comparison.
    if (LHS.getOpcode() == ISD::Constant)
      std::swap(LHS, RHS);
    break;
  case ISD::SETNE:
    TCC = MSP430CC::COND_NE;    // aka COND_NZ
    // Minor optimization: if LHS is a constant, swap operands, then the
    // constant can be folded into comparison.
    if (LHS.getOpcode() == ISD::Constant)
      std::swap(LHS, RHS);
    break;
  case ISD::SETULE:
    std::swap(LHS, RHS);
    LLVM_FALLTHROUGH;
  case ISD::SETUGE:
    // Turn lhs u>= rhs with lhs constant into rhs u< lhs+1, this allows us to
    // fold constant into instruction.
    if (const ConstantSDNode * C = dyn_cast<ConstantSDNode>(LHS)) {
      LHS = RHS;
      RHS = DAG.getConstant(C->getSExtValue() + 1, dl, C->getValueType(0));
      TCC = MSP430CC::COND_LO;
      break;
    }
    TCC = MSP430CC::COND_HS;    // aka COND_C
    break;
  case ISD::SETUGT:
    std::swap(LHS, RHS);
    LLVM_FALLTHROUGH;
  case ISD::SETULT:
    // Turn lhs u< rhs with lhs constant into rhs u>= lhs+1, this allows us to
    // fold constant into instruction.
    if (const ConstantSDNode * C = dyn_cast<ConstantSDNode>(LHS)) {
      LHS = RHS;
      RHS = DAG.getConstant(C->getSExtValue() + 1, dl, C->getValueType(0));
      TCC = MSP430CC::COND_HS;
      break;
    }
    TCC = MSP430CC::COND_LO;    // aka COND_NC
    break;
  case ISD::SETLE:
    std::swap(LHS, RHS);
    LLVM_FALLTHROUGH;
  case ISD::SETGE:
    // Turn lhs >= rhs with lhs constant into rhs < lhs+1, this allows us to
    // fold constant into instruction.
    if (const ConstantSDNode * C = dyn_cast<ConstantSDNode>(LHS)) {
      LHS = RHS;
      RHS = DAG.getConstant(C->getSExtValue() + 1, dl, C->getValueType(0));
      TCC = MSP430CC::COND_L;
      break;
    }
    TCC = MSP430CC::COND_GE;
    break;
  case ISD::SETGT:
    std::swap(LHS, RHS);
    LLVM_FALLTHROUGH;
  case ISD::SETLT:
    // Turn lhs < rhs with lhs constant into rhs >= lhs+1, this allows us to
    // fold constant into instruction.
    if (const ConstantSDNode * C = dyn_cast<ConstantSDNode>(LHS)) {
      LHS = RHS;
      RHS = DAG.getConstant(C->getSExtValue() + 1, dl, C->getValueType(0));
      TCC = MSP430CC::COND_GE;
      break;
    }
    TCC = MSP430CC::COND_L;
    break;
  }

  TargetCC = DAG.getConstant(TCC, dl, MVT::i8);
  return DAG.getNode(MSP430ISD::CMP, dl, MVT::Glue, LHS, RHS);
}


SDValue MSP430TargetLowering::LowerBR_CC(SDValue Op, SelectionDAG &DAG) const {
  SDValue Chain = Op.getOperand(0);
  ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(1))->get();
  SDValue LHS   = Op.getOperand(2);
  SDValue RHS   = Op.getOperand(3);
  SDValue Dest  = Op.getOperand(4);
  SDLoc dl  (Op);

  SDValue TargetCC;
  SDValue Flag = EmitCMP(LHS, RHS, TargetCC, CC, dl, DAG);

  return DAG.getNode(MSP430ISD::BR_CC, dl, Op.getValueType(),
                     Chain, Dest, TargetCC, Flag);
}

SDValue MSP430TargetLowering::LowerSETCC(SDValue Op, SelectionDAG &DAG) const {
  SDValue LHS   = Op.getOperand(0);
  SDValue RHS   = Op.getOperand(1);
  SDLoc dl  (Op);

  // If we are doing an AND and testing against zero, then the CMP
  // will not be generated.  The AND (or BIT) will generate the condition codes,
  // but they are different from CMP.
  // FIXME: since we're doing a post-processing, use a pseudoinstr here, so
  // lowering & isel wouldn't diverge.
  bool andCC = false;
  if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(RHS)) {
    if (RHSC->isNullValue() && LHS.hasOneUse() &&
        (LHS.getOpcode() == ISD::AND ||
         (LHS.getOpcode() == ISD::TRUNCATE &&
          LHS.getOperand(0).getOpcode() == ISD::AND))) {
      andCC = true;
    }
  }
  ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(2))->get();
  SDValue TargetCC;
  SDValue Flag = EmitCMP(LHS, RHS, TargetCC, CC, dl, DAG);

  // Get the condition codes directly from the status register, if its easy.
  // Otherwise a branch will be generated.  Note that the AND and BIT
  // instructions generate different flags than CMP, the carry bit can be used
  // for NE/EQ.
  bool Invert = false;
  bool Shift = false;
  bool Convert = true;
  switch (cast<ConstantSDNode>(TargetCC)->getZExtValue()) {
   default:
    Convert = false;
    break;
   case MSP430CC::COND_HS:
     // Res = SR & 1, no processing is required
     break;
   case MSP430CC::COND_LO:
     // Res = ~(SR & 1)
     Invert = true;
     break;
   case MSP430CC::COND_NE:
     if (andCC) {
       // C = ~Z, thus Res = SR & 1, no processing is required
     } else {
       // Res = ~((SR >> 1) & 1)
       Shift = true;
       Invert = true;
     }
     break;
   case MSP430CC::COND_E:
     Shift = true;
     // C = ~Z for AND instruction, thus we can put Res = ~(SR & 1), however,
     // Res = (SR >> 1) & 1 is 1 word shorter.
     break;
  }
  EVT VT = Op.getValueType();
  SDValue One  = DAG.getConstant(1, dl, VT);
  if (Convert) {
    SDValue SR = DAG.getCopyFromReg(DAG.getEntryNode(), dl, MSP430::SR,
                                    MVT::i16, Flag);
    if (Shift)
      // FIXME: somewhere this is turned into a SRL, lower it MSP specific?
      SR = DAG.getNode(ISD::SRA, dl, MVT::i16, SR, One);
    SR = DAG.getNode(ISD::AND, dl, MVT::i16, SR, One);
    if (Invert)
      SR = DAG.getNode(ISD::XOR, dl, MVT::i16, SR, One);
    return SR;
  } else {
    SDValue Zero = DAG.getConstant(0, dl, VT);
    SDVTList VTs = DAG.getVTList(Op.getValueType(), MVT::Glue);
    SDValue Ops[] = {One, Zero, TargetCC, Flag};
    return DAG.getNode(MSP430ISD::SELECT_CC, dl, VTs, Ops);
  }
}

SDValue MSP430TargetLowering::LowerSELECT_CC(SDValue Op,
                                             SelectionDAG &DAG) const {
  SDValue LHS    = Op.getOperand(0);
  SDValue RHS    = Op.getOperand(1);
  SDValue TrueV  = Op.getOperand(2);
  SDValue FalseV = Op.getOperand(3);
  ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(4))->get();
  SDLoc dl   (Op);

  SDValue TargetCC;
  SDValue Flag = EmitCMP(LHS, RHS, TargetCC, CC, dl, DAG);

  SDVTList VTs = DAG.getVTList(Op.getValueType(), MVT::Glue);
  SDValue Ops[] = {TrueV, FalseV, TargetCC, Flag};

  return DAG.getNode(MSP430ISD::SELECT_CC, dl, VTs, Ops);
}

SDValue MSP430TargetLowering::LowerSIGN_EXTEND(SDValue Op,
                                               SelectionDAG &DAG) const {
  SDValue Val = Op.getOperand(0);
  EVT VT      = Op.getValueType();
  SDLoc dl(Op);

  assert(VT == MVT::i16 && "Only support i16 for now!");

  return DAG.getNode(ISD::SIGN_EXTEND_INREG, dl, VT,
                     DAG.getNode(ISD::ANY_EXTEND, dl, VT, Val),
                     DAG.getValueType(Val.getValueType()));
}

SDValue
MSP430TargetLowering::getReturnAddressFrameIndex(SelectionDAG &DAG) const {
  MachineFunction &MF = DAG.getMachineFunction();
  MSP430MachineFunctionInfo *FuncInfo = MF.getInfo<MSP430MachineFunctionInfo>();
  int ReturnAddrIndex = FuncInfo->getRAIndex();
  auto PtrVT = getPointerTy(MF.getDataLayout());

  if (ReturnAddrIndex == 0) {
    // Set up a frame object for the return address.
    uint64_t SlotSize = MF.getDataLayout().getPointerSize();
    ReturnAddrIndex = MF.getFrameInfo().CreateFixedObject(SlotSize, -SlotSize,
                                                           true);
    FuncInfo->setRAIndex(ReturnAddrIndex);
  }

  return DAG.getFrameIndex(ReturnAddrIndex, PtrVT);
}

SDValue MSP430TargetLowering::LowerRETURNADDR(SDValue Op,
                                              SelectionDAG &DAG) const {
  MachineFrameInfo &MFI = DAG.getMachineFunction().getFrameInfo();
  MFI.setReturnAddressIsTaken(true);

  if (verifyReturnAddressArgumentIsConstant(Op, DAG))
    return SDValue();

  unsigned Depth = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
  SDLoc dl(Op);
  auto PtrVT = getPointerTy(DAG.getDataLayout());

  if (Depth > 0) {
    SDValue FrameAddr = LowerFRAMEADDR(Op, DAG);
    SDValue Offset =
        DAG.getConstant(DAG.getDataLayout().getPointerSize(), dl, MVT::i16);
    return DAG.getLoad(PtrVT, dl, DAG.getEntryNode(),
                       DAG.getNode(ISD::ADD, dl, PtrVT, FrameAddr, Offset),
                       MachinePointerInfo());
  }

  // Just load the return address.
  SDValue RetAddrFI = getReturnAddressFrameIndex(DAG);
  return DAG.getLoad(PtrVT, dl, DAG.getEntryNode(), RetAddrFI,
                     MachinePointerInfo());
}

SDValue MSP430TargetLowering::LowerFRAMEADDR(SDValue Op,
                                             SelectionDAG &DAG) const {
  MachineFrameInfo &MFI = DAG.getMachineFunction().getFrameInfo();
  MFI.setFrameAddressIsTaken(true);

  EVT VT = Op.getValueType();
  SDLoc dl(Op);  // FIXME probably not meaningful
  unsigned Depth = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
  SDValue FrameAddr = DAG.getCopyFromReg(DAG.getEntryNode(), dl,
                                         MSP430::FP, VT);
  while (Depth--)
    FrameAddr = DAG.getLoad(VT, dl, DAG.getEntryNode(), FrameAddr,
                            MachinePointerInfo());
  return FrameAddr;
}

SDValue MSP430TargetLowering::LowerVASTART(SDValue Op,
                                           SelectionDAG &DAG) const {
  MachineFunction &MF = DAG.getMachineFunction();
  MSP430MachineFunctionInfo *FuncInfo = MF.getInfo<MSP430MachineFunctionInfo>();
  auto PtrVT = getPointerTy(DAG.getDataLayout());

  // Frame index of first vararg argument
  SDValue FrameIndex =
      DAG.getFrameIndex(FuncInfo->getVarArgsFrameIndex(), PtrVT);
  const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue();

  // Create a store of the frame index to the location operand
  return DAG.getStore(Op.getOperand(0), SDLoc(Op), FrameIndex, Op.getOperand(1),
                      MachinePointerInfo(SV));
}

SDValue MSP430TargetLowering::LowerJumpTable(SDValue Op,
                                             SelectionDAG &DAG) const {
    JumpTableSDNode *JT = cast<JumpTableSDNode>(Op);
    auto PtrVT = getPointerTy(DAG.getDataLayout());
    SDValue Result = DAG.getTargetJumpTable(JT->getIndex(), PtrVT);
    return DAG.getNode(MSP430ISD::Wrapper, SDLoc(JT), PtrVT, Result);
}

/// getPostIndexedAddressParts - returns true by value, base pointer and
/// offset pointer and addressing mode by reference if this node can be
/// combined with a load / store to form a post-indexed load / store.
bool MSP430TargetLowering::getPostIndexedAddressParts(SDNode *N, SDNode *Op,
                                                      SDValue &Base,
                                                      SDValue &Offset,
                                                      ISD::MemIndexedMode &AM,
                                                      SelectionDAG &DAG) const {

  LoadSDNode *LD = cast<LoadSDNode>(N);
  if (LD->getExtensionType() != ISD::NON_EXTLOAD)
    return false;

  EVT VT = LD->getMemoryVT();
  if (VT != MVT::i8 && VT != MVT::i16)
    return false;

  if (Op->getOpcode() != ISD::ADD)
    return false;

  if (ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(Op->getOperand(1))) {
    uint64_t RHSC = RHS->getZExtValue();
    if ((VT == MVT::i16 && RHSC != 2) ||
        (VT == MVT::i8 && RHSC != 1))
      return false;

    Base = Op->getOperand(0);
    Offset = DAG.getConstant(RHSC, SDLoc(N), VT);
    AM = ISD::POST_INC;
    return true;
  }

  return false;
}


const char *MSP430TargetLowering::getTargetNodeName(unsigned Opcode) const {
  switch ((MSP430ISD::NodeType)Opcode) {
  case MSP430ISD::FIRST_NUMBER:       break;
  case MSP430ISD::RET_FLAG:           return "MSP430ISD::RET_FLAG";
  case MSP430ISD::RETI_FLAG:          return "MSP430ISD::RETI_FLAG";
  case MSP430ISD::RRA:                return "MSP430ISD::RRA";
  case MSP430ISD::RLA:                return "MSP430ISD::RLA";
  case MSP430ISD::RRC:                return "MSP430ISD::RRC";
  case MSP430ISD::RRCL:               return "MSP430ISD::RRCL";
  case MSP430ISD::CALL:               return "MSP430ISD::CALL";
  case MSP430ISD::Wrapper:            return "MSP430ISD::Wrapper";
  case MSP430ISD::BR_CC:              return "MSP430ISD::BR_CC";
  case MSP430ISD::CMP:                return "MSP430ISD::CMP";
  case MSP430ISD::SETCC:              return "MSP430ISD::SETCC";
  case MSP430ISD::SELECT_CC:          return "MSP430ISD::SELECT_CC";
  case MSP430ISD::DADD:               return "MSP430ISD::DADD";
  }
  return nullptr;
}

bool MSP430TargetLowering::isTruncateFree(Type *Ty1,
                                          Type *Ty2) const {
  if (!Ty1->isIntegerTy() || !Ty2->isIntegerTy())
    return false;

  return (Ty1->getPrimitiveSizeInBits() > Ty2->getPrimitiveSizeInBits());
}

bool MSP430TargetLowering::isTruncateFree(EVT VT1, EVT VT2) const {
  if (!VT1.isInteger() || !VT2.isInteger())
    return false;

  return (VT1.getSizeInBits() > VT2.getSizeInBits());
}

bool MSP430TargetLowering::isZExtFree(Type *Ty1, Type *Ty2) const {
  // MSP430 implicitly zero-extends 8-bit results in 16-bit registers.
  return 0 && Ty1->isIntegerTy(8) && Ty2->isIntegerTy(16);
}

bool MSP430TargetLowering::isZExtFree(EVT VT1, EVT VT2) const {
  // MSP430 implicitly zero-extends 8-bit results in 16-bit registers.
  return 0 && VT1 == MVT::i8 && VT2 == MVT::i16;
}

bool MSP430TargetLowering::isZExtFree(SDValue Val, EVT VT2) const {
  return isZExtFree(Val.getValueType(), VT2);
}

//===----------------------------------------------------------------------===//
//  Other Lowering Code
//===----------------------------------------------------------------------===//

MachineBasicBlock *
MSP430TargetLowering::EmitShiftInstr(MachineInstr &MI,
                                     MachineBasicBlock *BB) const {
  MachineFunction *F = BB->getParent();
  MachineRegisterInfo &RI = F->getRegInfo();
  DebugLoc dl = MI.getDebugLoc();
  const TargetInstrInfo &TII = *F->getSubtarget().getInstrInfo();

  unsigned Opc;
  bool ClearCarry = false;
  const TargetRegisterClass * RC;
  switch (MI.getOpcode()) {
  default: llvm_unreachable("Invalid shift opcode!");
  case MSP430::Shl8:
    Opc = MSP430::ADD8rr;
    RC = &MSP430::GR8RegClass;
    break;
  case MSP430::Shl16:
    Opc = MSP430::ADD16rr;
    RC = &MSP430::GR16RegClass;
    break;
  case MSP430::Sra8:
    Opc = MSP430::RRA8r;
    RC = &MSP430::GR8RegClass;
    break;
  case MSP430::Sra16:
    Opc = MSP430::RRA16r;
    RC = &MSP430::GR16RegClass;
    break;
  case MSP430::Srl8:
    ClearCarry = true;
    Opc = MSP430::RRC8r;
    RC = &MSP430::GR8RegClass;
    break;
  case MSP430::Srl16:
    ClearCarry = true;
    Opc = MSP430::RRC16r;
    RC = &MSP430::GR16RegClass;
    break;
  case MSP430::Rrcl8:
  case MSP430::Rrcl16: {
    BuildMI(*BB, MI, dl, TII.get(MSP430::BIC16rc), MSP430::SR)
      .addReg(MSP430::SR).addImm(1);
    unsigned SrcReg = MI.getOperand(1).getReg();
    unsigned DstReg = MI.getOperand(0).getReg();
    unsigned RrcOpc = MI.getOpcode() == MSP430::Rrcl16
                    ? MSP430::RRC16r : MSP430::RRC8r;
    BuildMI(*BB, MI, dl, TII.get(RrcOpc), DstReg)
      .addReg(SrcReg);
    MI.eraseFromParent(); // The pseudo instruction is gone now.
    return BB;
  }
  }

  const BasicBlock *LLVM_BB = BB->getBasicBlock();
  MachineFunction::iterator I = ++BB->getIterator();

  // Create loop block
  MachineBasicBlock *LoopBB = F->CreateMachineBasicBlock(LLVM_BB);
  MachineBasicBlock *RemBB  = F->CreateMachineBasicBlock(LLVM_BB);

  F->insert(I, LoopBB);
  F->insert(I, RemBB);

  // Update machine-CFG edges by transferring all successors of the current
  // block to the block containing instructions after shift.
  RemBB->splice(RemBB->begin(), BB, std::next(MachineBasicBlock::iterator(MI)),
                BB->end());
  RemBB->transferSuccessorsAndUpdatePHIs(BB);

  // Add edges BB => LoopBB => RemBB, BB => RemBB, LoopBB => LoopBB
  BB->addSuccessor(LoopBB);
  BB->addSuccessor(RemBB);
  LoopBB->addSuccessor(RemBB);
  LoopBB->addSuccessor(LoopBB);

  unsigned ShiftAmtReg = RI.createVirtualRegister(&MSP430::GR8RegClass);
  unsigned ShiftAmtReg2 = RI.createVirtualRegister(&MSP430::GR8RegClass);
  unsigned ShiftReg = RI.createVirtualRegister(RC);
  unsigned ShiftReg2 = RI.createVirtualRegister(RC);
  unsigned ShiftAmtSrcReg = MI.getOperand(2).getReg();
  unsigned SrcReg = MI.getOperand(1).getReg();
  unsigned DstReg = MI.getOperand(0).getReg();

  // BB:
  // cmp 0, N
  // je RemBB
  BuildMI(BB, dl, TII.get(MSP430::CMP8ri))
    .addReg(ShiftAmtSrcReg).addImm(0);
  BuildMI(BB, dl, TII.get(MSP430::JCC))
    .addMBB(RemBB)
    .addImm(MSP430CC::COND_E);

  // LoopBB:
  // ShiftReg = phi [%SrcReg, BB], [%ShiftReg2, LoopBB]
  // ShiftAmt = phi [%N, BB],      [%ShiftAmt2, LoopBB]
  // ShiftReg2 = shift ShiftReg
  // ShiftAmt2 = ShiftAmt - 1;
  BuildMI(LoopBB, dl, TII.get(MSP430::PHI), ShiftReg)
    .addReg(SrcReg).addMBB(BB)
    .addReg(ShiftReg2).addMBB(LoopBB);
  BuildMI(LoopBB, dl, TII.get(MSP430::PHI), ShiftAmtReg)
    .addReg(ShiftAmtSrcReg).addMBB(BB)
    .addReg(ShiftAmtReg2).addMBB(LoopBB);
  if (ClearCarry)
    BuildMI(LoopBB, dl, TII.get(MSP430::BIC16rc), MSP430::SR)
      .addReg(MSP430::SR).addImm(1);
  if (Opc == MSP430::ADD8rr || Opc == MSP430::ADD16rr)
    BuildMI(LoopBB, dl, TII.get(Opc), ShiftReg2)
      .addReg(ShiftReg)
      .addReg(ShiftReg);
  else
    BuildMI(LoopBB, dl, TII.get(Opc), ShiftReg2)
      .addReg(ShiftReg);
  BuildMI(LoopBB, dl, TII.get(MSP430::SUB8ri), ShiftAmtReg2)
    .addReg(ShiftAmtReg).addImm(1);
  BuildMI(LoopBB, dl, TII.get(MSP430::JCC))
    .addMBB(LoopBB)
    .addImm(MSP430CC::COND_NE);

  // RemBB:
  // DestReg = phi [%SrcReg, BB], [%ShiftReg, LoopBB]
  BuildMI(*RemBB, RemBB->begin(), dl, TII.get(MSP430::PHI), DstReg)
    .addReg(SrcReg).addMBB(BB)
    .addReg(ShiftReg2).addMBB(LoopBB);

  MI.eraseFromParent(); // The pseudo instruction is gone now.
  return RemBB;
}

MachineBasicBlock *
MSP430TargetLowering::EmitInstrWithCustomInserter(MachineInstr &MI,
                                                  MachineBasicBlock *BB) const {
  unsigned Opc = MI.getOpcode();

  if (Opc == MSP430::Shl8  || Opc == MSP430::Shl16 ||
      Opc == MSP430::Sra8  || Opc == MSP430::Sra16 ||
      Opc == MSP430::Srl8  || Opc == MSP430::Srl16 ||
      Opc == MSP430::Rrcl8 || Opc == MSP430::Rrcl16)
    return EmitShiftInstr(MI, BB);

  const TargetInstrInfo &TII = *BB->getParent()->getSubtarget().getInstrInfo();
  DebugLoc dl = MI.getDebugLoc();

  assert((Opc == MSP430::Select16 || Opc == MSP430::Select8) &&
         "Unexpected instr type to insert");

  // To "insert" a SELECT instruction, we actually have to insert the diamond
  // control-flow pattern.  The incoming instruction knows the destination vreg
  // to set, the condition code register to branch on, the true/false values to
  // select between, and a branch opcode to use.
  const BasicBlock *LLVM_BB = BB->getBasicBlock();
  MachineFunction::iterator I = ++BB->getIterator();

  //  thisMBB:
  //  ...
  //   TrueVal = ...
  //   cmpTY ccX, r1, r2
  //   jCC copy1MBB
  //   fallthrough --> copy0MBB
  MachineBasicBlock *thisMBB = BB;
  MachineFunction *F = BB->getParent();
  MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
  MachineBasicBlock *copy1MBB = F->CreateMachineBasicBlock(LLVM_BB);
  F->insert(I, copy0MBB);
  F->insert(I, copy1MBB);
  // Update machine-CFG edges by transferring all successors of the current
  // block to the new block which will contain the Phi node for the select.
  copy1MBB->splice(copy1MBB->begin(), BB,
                   std::next(MachineBasicBlock::iterator(MI)), BB->end());
  copy1MBB->transferSuccessorsAndUpdatePHIs(BB);
  // Next, add the true and fallthrough blocks as its successors.
  BB->addSuccessor(copy0MBB);
  BB->addSuccessor(copy1MBB);

  BuildMI(BB, dl, TII.get(MSP430::JCC))
      .addMBB(copy1MBB)
      .addImm(MI.getOperand(3).getImm());

  //  copy0MBB:
  //   %FalseValue = ...
  //   # fallthrough to copy1MBB
  BB = copy0MBB;

  // Update machine-CFG edges
  BB->addSuccessor(copy1MBB);

  //  copy1MBB:
  //   %Result = phi [ %FalseValue, copy0MBB ], [ %TrueValue, thisMBB ]
  //  ...
  BB = copy1MBB;
  BuildMI(*BB, BB->begin(), dl, TII.get(MSP430::PHI), MI.getOperand(0).getReg())
      .addReg(MI.getOperand(2).getReg())
      .addMBB(copy0MBB)
      .addReg(MI.getOperand(1).getReg())
      .addMBB(thisMBB);

  MI.eraseFromParent(); // The pseudo instruction is gone now.
  return BB;
}