forked from jbremer/darm
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy paththumb2-decoder.c
1535 lines (1255 loc) · 36.3 KB
/
thumb2-decoder.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
Copyright (c) 2013, Jurriaan Bremer
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
* Neither the name of the darm developer(s) nor the names of its
contributors may be used to endorse or promote products derived from this
software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
*/
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include "darm.h"
#include "darm-internal.h"
#include "darm-tbl.h"
#include "thumb-tbl.h"
#include "thumb2-tbl.h"
#include "thumb2.h"
darm_instr_t thumb2_load_store_multiple(darm_t *d, uint16_t w, uint16_t w2);
darm_instr_t thumb2_load_store_dual(darm_t *d, uint16_t w, uint16_t w2);
darm_instr_t thumb2_data_shifted_reg(darm_t *d, uint16_t w, uint16_t w2);
darm_instr_t thumb2_coproc_simd(darm_t *d, uint16_t w, uint16_t w2);
darm_instr_t thumb2_modified_immediate(darm_t *d, uint16_t w, uint16_t w2);
darm_instr_t thumb2_plain_immediate(darm_t *d, uint16_t w, uint16_t w2);
darm_instr_t thumb2_branch_misc_ctrl(darm_t *d, uint16_t w, uint16_t w2);
darm_instr_t thumb2_store_single_item(darm_t *d, uint16_t w, uint16_t w2);
darm_instr_t thumb2_data_reg(darm_t *d, uint16_t w, uint16_t w2);
darm_instr_t thumb2_mult_acc_diff(darm_t *d, uint16_t w, uint16_t w2);
darm_instr_t thumb2_long_mult_acc(darm_t *d, uint16_t w, uint16_t w2);
darm_instr_t thumb2_load_byte_hints(darm_t *d, uint16_t w, uint16_t w2);
darm_instr_t thumb2_load_word(darm_t *d, uint16_t w, uint16_t w2);
darm_instr_t thumb2_load_halfword_hints(darm_t *d, uint16_t w, uint16_t w2);
darm_instr_t thumb2_decode_instruction(darm_t *d, uint16_t w, uint16_t w2)
{
uint32_t op2 = (w >> 4) & 0x7f;
switch ((w >> 11) & b11) {
case 1:
op2 &= 0x64;
if(op2 == 0) {
// load, store multiple
return thumb2_load_store_multiple(d, w, w2);
}
else if(op2 == b100) {
// load/store dual, load/store exclusive, table branch
return thumb2_load_store_dual(d, w, w2);
}
else if(((op2 >> 5) & b11) == b1) {
// dataprocessing (shifted register)
return thumb2_data_shifted_reg(d, w, w2);
}
else if(((op2 >> 6) & b1) == b1) {
// coproc, simd, fpu
return thumb2_coproc_simd(d, w, w2);
}
break;
case 2:
op2 = (op2 & 0x20) >> 5;
if(op2 == 0 && (w2 & 0x8000) == 0) {
// dataprocessing (modified immediate)
return thumb2_modified_immediate(d, w, w2);
}
else if(op2 == 1 && (w2 & 0x8000) == 0) {
// dataprocessing (plain binary immediate)
return thumb2_plain_immediate(d, w, w2);
}
else if((w2 & 0x8000) == 0x8000) {
// branches and miscellaneous control
return thumb2_branch_misc_ctrl(d, w, w2);
}
break;
case 3:
if((op2 & 0x71) == 0) {
// store single data item
return thumb2_store_single_item(d, w, w2);
}
else if((op2 & 0x71) == 0x10) {
// Advanced SIMD element or structure load/store instructions
// TODO: implement
return I_INVLD;
}
else if((op2 & 0x70) == 0x20) {
// data-processing (register)
return thumb2_data_reg(d, w, w2);
}
else if((op2 & 0x78) == 0x30) {
// multiply, multiply accumulate, and absolute difference
return thumb2_mult_acc_diff(d, w, w2);
}
else if((op2 & 0x78) == 0x38) {
// long multiply, long multiply accumulate, and divide
return thumb2_long_mult_acc(d, w, w2);
}
else {
switch (op2 & 0x67) {
case 1:
// load byte, memory hints
return thumb2_load_byte_hints(d, w, w2);
case 3:
// load halfword, memory hints
return thumb2_load_halfword_hints(d, w, w2);
case 5:
// load word
return thumb2_load_word(d, w, w2);
}
break;
}
}
// TODO handle other co-proc case
return I_INVLD;
}
darm_instr_t thumb2_load_store_multiple(darm_t *d, uint16_t w, uint16_t w2)
{
(void) w2;
uint32_t op = (w >> 7) & b11;
uint32_t L = (w >> 4) & b1;
uint32_t W_Rn = ((w >> 1) & 0x10) | (w & b1111);
d->instr_type = T_THUMB2_RN_REG;
d->instr_imm_type = T_THUMB2_NO_IMM;
d->instr_flag_type = T_THUMB2_REGLIST_FLAG;
switch (op) {
case 0:
case 3:
d->instr_type = T_THUMB2_NO_REG;
d->instr_flag_type = T_THUMB2_NO_FLAG;
if(L == 0) {
return I_SRS;
}
else if(L == 1) {
return I_RFE;
}
break;
case 1:
if(L == 0) {
return I_STM;
}
if(W_Rn == 0x1d) {
d->instr_type = T_THUMB2_NO_REG;
return I_POP;
}
d->instr_flag_type = T_THUMB2_WP_REGLIST_FLAG;
return I_LDM;
case 2:
if(L == 0) {
if(W_Rn == 0x1d) {
d->instr_type = T_THUMB2_NO_REG;
return I_PUSH;
}
return I_STMDB;
}
d->instr_flag_type = T_THUMB2_WP_REGLIST_FLAG;
return I_LDMDB;
}
return I_INVLD;
}
darm_instr_t thumb2_load_store_dual(darm_t *d, uint16_t w, uint16_t w2)
{
uint32_t op1 = (w >> 7) & b11;
uint32_t op2 = (w >> 4) & b11;
uint32_t op3 = (w2 >> 4) & b1111;
uint32_t Rn = w & b1111;
d->instr_type = T_THUMB2_RN_RT_REG;
d->instr_imm_type = T_THUMB2_IMM8;;
d->instr_flag_type = T_THUMB2_NO_FLAG;
if(op1 == 0 && op2 == 0) {
d->instr_type = T_THUMB2_RN_RD_RT_REG;
return I_STREX;
}
else if(op1 == 0 && op2 == 1) {
return I_LDREX;
}
else if((op1 & 2) == 0 && op2 == 2) {
d->instr_type = T_THUMB2_RN_RT_RT2_REG;
d->instr_flag_type = T_THUMB2_WUP_FLAG;
return I_STRD; // immediate
}
else if(((op1 & 2) == 0 && op2 == 3) ||
((op1 & 2) == 2 && (op2 & 1) == 1)) {
d->instr_flag_type = T_THUMB2_WUP_FLAG;
if(Rn == b1111) {
d->instr_type = T_THUMB2_RT_RT2_REG;
}
else {
d->instr_type = T_THUMB2_RN_RT_RT2_REG;
}
return I_LDRD; // literal and immediate
}
else if((op1 & 2) == 2 && (op2 & 1) == 0) {
d->instr_type = T_THUMB2_RN_RT_RT2_REG;
d->instr_flag_type = T_THUMB2_WUP_FLAG;
return I_STRD; // immediate
}
else if(op1 == 1 && op2 == 0) {
d->instr_imm_type = T_THUMB2_NO_IMM;
d->instr_type = T_THUMB2_RN_RD_RT_REG;
switch (op3) {
case 4:
return I_STREXB;
case 5:
return I_STREXH;
case 7:
d->instr_type = T_THUMB2_RN_RD_RT_RT2_REG;
return I_STREXD;
}
}
else if(op1 == 1 && op2 == 1) {
d->instr_imm_type = T_THUMB2_NO_IMM;
switch (op3) {
case 0:
d->instr_type = T_THUMB2_RN_RM_REG;
d->instr_imm_type = T_THUMB2_NO_IMM;
return I_TBB;
case 1:
d->instr_type = T_THUMB2_RN_RM_REG;
d->instr_imm_type = T_THUMB2_NO_IMM;
return I_TBH;
case 4:
return I_LDREXB;
case 5:
return I_LDREXH;
case 7:
d->instr_type = T_THUMB2_RN_RT_RT2_REG;
return I_LDREXD;
}
}
return I_INVLD;
}
darm_instr_t thumb2_move_shift(darm_t *d, uint16_t w, uint16_t w2)
{
(void) w;
uint32_t type = (w2>>4) & b11;
uint32_t imm3_imm2 = ((w2>>10) & 0x1C) | ((w2>>6) & b11);
d->instr_type = T_THUMB2_RD_RM_REG;
d->instr_imm_type = T_THUMB2_IMM2_IMM3;
d->instr_flag_type = T_THUMB2_S_FLAG;
switch (type) {
case 0:
if(imm3_imm2 == 0) {
d->instr_imm_type = T_THUMB2_NO_IMM;
return I_MOV;
}
return I_LSL;
case 1:
return I_LSR;
case 2:
return I_ASR;
case 3:
if(imm3_imm2 == 0) {
d->instr_imm_type = T_THUMB2_NO_IMM;
return I_RRX;
}
return I_ROR;
}
return I_INVLD;
}
darm_instr_t thumb2_data_shifted_reg(darm_t *d, uint16_t w, uint16_t w2)
{
uint32_t op = (w >> 5) & b1111;
uint32_t Rn = w & b1111;
uint32_t Rd_S = ((w2 >> 7) & 0x1e) | ((w >> 4) & 1);
d->instr_type = T_THUMB2_RN_RD_RM_REG;
d->instr_imm_type = T_THUMB2_IMM2_IMM3;
d->instr_flag_type = T_THUMB2_S_TYPE_FLAG;
switch (op) {
case 0:
if(Rd_S == 0x1f) {
d->instr_type = T_THUMB2_RN_RM_REG;
d->instr_flag_type = T_THUMB2_TYPE_FLAG;
return I_TST;
}
return I_AND;
case 1:
return I_BIC;
case 2:
if(Rn == b1111) {
return thumb2_move_shift(d, w, w2);
}
return I_ORR;
case 3:
if(Rn == b1111) {
d->instr_type = T_THUMB2_RD_RM_REG;
return I_MVN;
}
return I_ORN;
case 4:
if(Rd_S == 0x1f) {
d->instr_type = T_THUMB2_RN_RM_REG;
d->instr_flag_type = T_THUMB2_TYPE_FLAG;
return I_TEQ;
}
return I_EOR;
case 6:
d->instr_flag_type = T_THUMB2_S_FLAG;
return I_PKH;
case 8:
if(Rd_S == 0x1f) {
d->instr_type = T_THUMB2_RN_RM_REG;
d->instr_flag_type = T_THUMB2_TYPE_FLAG;
return I_CMN;
}
return I_ADD;
case 10:
return I_ADC;
case 11:
return I_SBC;
case 13:
if(Rd_S == 0x1f) {
d->instr_type = T_THUMB2_RN_RM_REG;
d->instr_flag_type = T_THUMB2_TYPE_FLAG;
return I_CMP;
}
return I_SUB;
case 14:
return I_RSB;
}
return I_INVLD;
}
darm_instr_t thumb2_modified_immediate(darm_t *d, uint16_t w, uint16_t w2)
{
uint32_t op = (w >> 5) & b1111;
uint32_t Rn = w & b1111;
uint32_t Rd_S = ((w2 >> 7) & 0x1e) | ((w >> 4) & 1);
d->instr_type = T_THUMB2_RN_RD_REG;
d->instr_imm_type = T_THUMB2_IMM1_IMM3_IMM8;
d->instr_flag_type = T_THUMB2_S_FLAG;
switch (op) {
case 0:
if(Rd_S == 0x1f) {
d->instr_type = T_THUMB2_RN_REG;
d->instr_flag_type = T_THUMB2_NO_FLAG;
return I_TST;
}
return I_AND;
case 1:
return I_BIC;
case 2:
if(Rn == b1111) {
d->instr_type = T_THUMB2_RD_REG;
return I_MOV;
}
return I_ORR;
case 3:
if(Rn == b1111) {
d->instr_type = T_THUMB2_RD_REG;
return I_MVN;
}
return I_ORN;
case 4:
if(Rd_S == 0x1f) {
d->instr_type = T_THUMB2_RN_REG;
d->instr_flag_type = T_THUMB2_NO_FLAG;
return I_TEQ;
}
return I_EOR;
case 8:
if(Rd_S == 0x1f) {
d->instr_type = T_THUMB2_RN_REG;
d->instr_flag_type = T_THUMB2_NO_FLAG;
return I_CMN;
}
return I_ADD;
case 10:
return I_ADC;
case 11:
return I_SBC;
case 13:
if(Rd_S == 0x1f) {
d->instr_type = T_THUMB2_RN_REG;
d->instr_flag_type = T_THUMB2_NO_FLAG;
return I_CMP;
}
return I_SUB;
case 14:
return I_RSB;
}
return I_INVLD;
}
darm_instr_t thumb2_plain_immediate(darm_t *d, uint16_t w, uint16_t w2)
{
uint32_t op = (w >> 4) & 0x1f;
uint32_t Rn = w & b1111;
d->instr_type = T_THUMB2_RN_RD_REG;
d->instr_imm_type = T_THUMB2_IMM1_IMM3_IMM8;
d->instr_flag_type = T_THUMB2_NO_FLAG;
switch (op) {
case 0:
return Rn == b1111 ? I_ADR : I_ADDW;
case 4:
d->instr_type = T_THUMB2_RD_REG;
return I_MOVW;
case 10:
return Rn == b1111 ? I_ADR : I_SUBW;
case 12:
d->instr_type = T_THUMB2_RD_REG;
return I_MOVT;
case 16:
d->instr_imm_type = T_THUMB2_IMM2_IMM3;
return I_SSAT;
case 18:
if((w2 & 0x70c0) == 0) {
d->instr_imm_type = T_THUMB2_NO_IMM;
return I_SSAT16;
}
d->instr_imm_type = T_THUMB2_IMM2_IMM3;
return I_SSAT;
case 20:
d->instr_imm_type = T_THUMB2_IMM2_IMM3;
return I_SBFX;
case 22:
d->instr_imm_type = T_THUMB2_IMM2_IMM3;
if(Rn == b1111) {
d->instr_type = T_THUMB2_RD_REG;
return I_BFC;
}
return I_BFI;
case 24:
d->instr_imm_type = T_THUMB2_IMM2_IMM3;
return I_USAT;
case 26:
if((w2 & 0x70c0) == 0) {
d->instr_imm_type = T_THUMB2_NO_IMM;
return I_USAT16;
}
d->instr_imm_type = T_THUMB2_IMM2_IMM3;
return I_USAT;
case 28:
d->instr_imm_type = T_THUMB2_IMM2_IMM3;
return I_UBFX;
}
return I_INVLD;
}
darm_instr_t thumb2_proc_state(darm_t *d, uint16_t w, uint16_t w2)
{
(void) d; (void) w;
uint32_t op1 = (w2 >> 8) & b111;
uint32_t op2 = w2 & 0xff;
if(op1 == 0) {
switch (op2) {
case 0:
return I_NOP;
case 1:
return I_YIELD;
case 2:
return I_WFE;
case 3:
return I_WFI;
case 4:
return I_SEV;
default:
if(((op2 >> 4) & b1111) == b1111) {
return I_DBG;
}
}
}
else {
return I_CPS;
}
return I_INVLD;
}
darm_instr_t thumb2_misc_ctrl(darm_t *d, uint16_t w, uint16_t w2)
{
(void) d; (void) w;
uint32_t op = (w2 >> 4) & b111;
switch (op) {
case 0: case 1:
// TODO: ENTERX, LEAVEX
return I_NOP;
case 2:
return I_CLREX;
case 4:
return I_DSB;
case 5:
return I_DMB;
case 6:
return I_ISB;
}
return I_INVLD;
}
darm_instr_t thumb2_branch_misc_ctrl(darm_t *d, uint16_t w, uint16_t w2)
{
uint32_t op = (w >> 4) & 0x7f;
uint32_t op1 = (w2 >> 12) & b111;
uint32_t imm8 = w2 & 0xff;
d->instr_type = T_THUMB2_NO_REG;
d->instr_imm_type = T_THUMB2_NO_IMM;
d->instr_flag_type = T_THUMB2_NO_FLAG;
if(op1 == 0 && op == 0xfe) {
// TODO return I_HVC
return I_NOP;
}
else if(op1 == 0 && op == 0xff) {
return I_SMC;
}
else if((op1 & b101) == 1) {
d->instr_flag_type = T_THUMB2_S_FLAG;
return I_B;
}
else if(op1 == 2 && op == 0xff) {
return I_UDF;
}
else if((op1 & b101) == 0) {
if((op & 0x38) != 0x38) {
d->instr_flag_type = T_THUMB2_S_FLAG;
return I_B;
}
else if((op & 0x7e) == 0x38 && (imm8 & 0x10) == 0x10) {
return I_MSR; // banked register
}
else if(op == 0x38 && (imm8 & 0x10) == 0) {
d->instr_type = T_THUMB2_RN_REG;
return I_MSR; // register
}
else if(op == 0x3a) {
return thumb2_proc_state(d, w, w2);
}
else if(op == 0x3b) {
return thumb2_misc_ctrl(d, w, w2);
}
else if(op == 0x3c) {
d->instr_type = T_THUMB2_RM_REG;
return I_BXJ;
}
else if(op == 0x3e && (imm8 & 0x10) == 0) {
d->instr_type = T_THUMB2_RD_REG;
return I_MRS;
}
}
else if((op1 & b101) == b100) {
d->instr_flag_type = T_THUMB2_S_FLAG;
return I_BLX;
}
else if((op1 & b101) == b101) {
d->instr_flag_type = T_THUMB2_S_FLAG;
return I_BL;
}
return I_INVLD;
}
darm_instr_t thumb2_store_single_item(darm_t *d, uint16_t w, uint16_t w2)
{
uint32_t op1 = (w >> 5) & b111;
uint32_t op2 = (w2 >> 6) & 0x3f;
d->instr_type = T_THUMB2_RN_RT_REG;
d->instr_imm_type = T_THUMB2_IMM8;
d->instr_flag_type = T_THUMB2_NO_FLAG;
switch (op1) {
case 0:
if(op2 == 0) {
d->instr_type = T_THUMB2_RN_RM_RT_REG;
d->instr_imm_type = T_THUMB2_IMM2;
return I_STRB; // register
}
else if((op2 & 0x3c) == 0x38) {
return I_STRBT;
}
else if((op2 & 0x3c) == 0x30 || (op2 & 0x24) == 0x24) {
d->instr_flag_type = T_THUMB2_WUP_FLAG;
return I_STRB; // immediate 8 bit
}
break;
case 1:
if(op2 == 0) {
d->instr_type = T_THUMB2_RN_RM_RT_REG;
d->instr_imm_type = T_THUMB2_IMM2;
return I_STRH; // register
}
else if((op2 & 0x3c) == 0x38) {
return I_STRHT;
}
else if((op2 & 0x3c) == 0x30 || (op2 & 0x24) == 0x24) {
d->instr_flag_type = T_THUMB2_WUP_FLAG;
return I_STRH; // immediate 8 bit
}
break;
case 2:
if(op2 == 0) {
d->instr_type = T_THUMB2_RN_RM_RT_REG;
d->instr_imm_type = T_THUMB2_IMM2;
return I_STR; // register
}
else if((op2 & 0x3c) == 0x38) {
return I_STRT;
}
else if((op2 & 0x3c) == 0x30 || (op2 & 0x24) == 0x24) {
// PUSH pseudo single register if Rn == SP,
// P and W are set, and imm == 4
if((w & 0xf) == b1101 && (w2 & 0xfff) == 0xd04) {
d->instr_type = T_THUMB2_RT_REG;
d->instr_imm_type = T_THUMB2_NO_IMM;
d->instr_flag_type = T_THUMB2_NO_FLAG;
return I_PUSH;
}
d->instr_flag_type = T_THUMB2_WUP_FLAG;
return I_STR; // immediate 8 bit
}
break;
case 4:
d->instr_imm_type = T_THUMB2_IMM12;
return I_STRB; // immediate 12 bit
case 5:
d->instr_imm_type = T_THUMB2_IMM12;
return I_STRH; // immediate 12 bit
case 6:
d->instr_imm_type = T_THUMB2_IMM12;
return I_STR; // immediate 12 bit
}
return I_INVLD;
}
darm_instr_t thumb2_load_byte_hints(darm_t *d, uint16_t w, uint16_t w2)
{
uint32_t op1 = (w >> 7) & b11;
uint32_t op2 = (w2 >> 6) & 0x3f;
uint32_t Rn = w & b1111;
uint32_t Rt = (w2 >> 12) & b1111;
d->instr_type = T_THUMB2_RN_RT_REG;
d->instr_imm_type = T_THUMB2_IMM12;
d->instr_flag_type = T_THUMB2_NO_FLAG;
if((op1 & 2) == 0 && Rn == b1111) {
d->instr_flag_type = T_THUMB2_U_FLAG;
if(Rt == b1111) {
d->instr_imm_type = T_THUMB2_NO_REG;
return I_PLD; // literal
}
d->instr_type = T_THUMB2_RT_REG;
return I_LDRB; // literal
}
else if((op1 & 2) == 2 && Rn == b1111) {
d->instr_flag_type = T_THUMB2_U_FLAG;
if(Rt == b1111) {
d->instr_imm_type = T_THUMB2_NO_REG;
return I_PLI; // immediate, literal
}
d->instr_type = T_THUMB2_RT_REG;
return I_LDRSB; // literal
}
else if(op1 == 0) {
if(op2 == 0) {
d->instr_imm_type = T_THUMB2_IMM2;
if(Rt == b1111) {
d->instr_type = T_THUMB2_RN_RM_REG;
return I_PLD; // PLD/PLDW register
}
d->instr_type = T_THUMB2_RN_RM_RT_REG;
return I_LDRB; // register
}
else if((op2 & 0x24) == 0x24) {
d->instr_imm_type = T_THUMB2_IMM8;
d->instr_flag_type = T_THUMB2_WUP_FLAG;
return I_LDRB; // immediate
}
else if((op2 & 0x3c) == 0x30) {
d->instr_imm_type = T_THUMB2_IMM8;
if(Rt == b1111) {
d->instr_type = T_THUMB2_RN_REG;
return I_PLD; // PLD/PLDW immediate
}
d->instr_flag_type = T_THUMB2_WUP_FLAG;
return I_LDRB; // immediate
}
else if((op2 & 0x3c) == 0x38) {
d->instr_imm_type = T_THUMB2_IMM8;
return I_LDRBT;
}
}
else if(op1 == 1) {
if(Rt == b1111) {
d->instr_type = T_THUMB2_RN_REG;
return I_PLD; // PLD/PLDW immediate 12
}
return I_LDRB; // immediate 12
}
else if(op1 == 2) {
if(op2 == 0) {
d->instr_imm_type = T_THUMB2_IMM2;
if(Rt == b1111) {
d->instr_type = T_THUMB2_RN_RM_REG;
return I_PLI; // PLI register
}
d->instr_type = T_THUMB2_RN_RM_RT_REG;
return I_LDRSB; // register
}
else if((op2 & 0x24) == 0x24) {
d->instr_imm_type = T_THUMB2_IMM8;
d->instr_flag_type = T_THUMB2_WUP_FLAG;
return I_LDRSB; // immediate 8
}
else if((op2 & 0x3C) == 0x30) {
d->instr_imm_type = T_THUMB2_IMM8;
if(Rt == b1111) {
d->instr_type = T_THUMB2_RN_REG;
return I_PLI; // PLI immediate/literal
}
d->instr_flag_type = T_THUMB2_WUP_FLAG;
return I_LDRSB; // immediate 8
}
else if((op2 & 0x3C) == 0x38) {
d->instr_imm_type = T_THUMB2_IMM8;
return I_LDRSBT;
}
}
else if(op1 == 3) {
if(Rt == b1111) {
d->instr_type = T_THUMB2_RN_REG;
return I_PLI; // PLI literal/immediate
}
return I_LDRSB; // immediate 12
}
return I_INVLD;
}
darm_instr_t thumb2_load_halfword_hints(darm_t *d, uint16_t w, uint16_t w2)
{
uint32_t op1 = (w >> 7) & b11;
uint32_t op2 = (w2 >> 6) & 0x3f;
uint32_t Rn = w & b1111;
uint32_t Rt = (w2 >> 12) & b1111;
d->instr_type = T_THUMB2_RN_RT_REG;
d->instr_imm_type = T_THUMB2_IMM12;
d->instr_flag_type = T_THUMB2_NO_FLAG;
if((op1 & 2) == 0 && Rn == b1111) {
d->instr_flag_type = T_THUMB2_U_FLAG;
if(Rt == b1111) {
return I_PLD; // literal
}
d->instr_type = T_THUMB2_RT_REG;
return I_LDRH; // literal
}
else if((op1 & 2) == 2 && Rn == b1111) {
if(Rt == b1111) {
return I_NOP; // mem hint
}
d->instr_flag_type = T_THUMB2_U_FLAG;
d->instr_type = T_THUMB2_RT_REG;
return I_LDRSH; // literal
}
else if(op1 == 0) {
if(op2 == 0) {
d->instr_imm_type = T_THUMB2_IMM2;
if(Rt == b1111) {
d->instr_type = T_THUMB2_RN_RM_REG;
return I_PLD; // PLD/PLDW register
}
d->instr_type = T_THUMB2_RN_RM_RT_REG;
return I_LDRH; // register
}
else if((op2 & 0x24) == 0x24) {
d->instr_imm_type = T_THUMB2_IMM8;
d->instr_flag_type = T_THUMB2_WUP_FLAG;
return I_LDRH; // immediate 8 bit
}
else if((op2 & 0x3c) == 0x30) {
if(Rt == b1111) {
d->instr_type = T_THUMB2_RN_REG;
d->instr_imm_type = T_THUMB2_IMM8;
return I_PLD; // PLD/PLDW immediate 8 bit
}
d->instr_imm_type = T_THUMB2_IMM8;
d->instr_flag_type = T_THUMB2_WUP_FLAG;
return I_LDRH; // immediate 8 bit
}
else if((op2 & 0x3c) == 0x38) {
d->instr_imm_type = T_THUMB2_IMM8;
return I_LDRHT;
}
}
else if(op1 == 1) {
if(Rt == b1111) {
d->instr_type = T_THUMB2_RN_REG;
return I_PLD; // PLD/PLDW immediate 12 bit
}
return I_LDRH; // immediate 12 bit
}
else if(op1 == 2) {
if(op2 == 0) {
if(Rt == b1111) {
return I_NOP;
}
d->instr_imm_type = T_THUMB2_IMM2;
d->instr_type = T_THUMB2_RN_RM_RT_REG;
return I_LDRSH; // register
}
else if((op2 & 0x24) == 0x24) {
d->instr_imm_type = T_THUMB2_IMM8;
d->instr_flag_type = T_THUMB2_WUP_FLAG;
return I_LDRSH; // immediate 8 bit
}
else if((op2 & 0x3c) == 0x30) {
if(Rt == b1111) {
return I_NOP;
}
d->instr_imm_type = T_THUMB2_IMM8;
d->instr_flag_type = T_THUMB2_WUP_FLAG;
return I_LDRSH; // immediate 8 bit
}
else if ((op2 & 0x3c) == 0x38) {
d->instr_imm_type = T_THUMB2_IMM8;
return I_LDRSHT;
}
}
else if(op1 == 3) {
if(Rt == b1111) {
return I_NOP;
}
return I_LDRSH; // immediate 12 bit
}
return I_INVLD;
}
darm_instr_t thumb2_load_word(darm_t *d, uint16_t w, uint16_t w2)
{
uint32_t op1 = (w >> 7) & b11;
uint32_t op2 = (w2 >> 6) & 0x3f;
uint32_t Rn = w & b1111;
d->instr_type = T_THUMB2_RN_RT_REG;
d->instr_imm_type = T_THUMB2_IMM8;
d->instr_flag_type = T_THUMB2_NO_FLAG;
if((op1 & 2) == 0 && Rn == b1111) {
d->instr_type = T_THUMB2_RT_REG;
d->instr_imm_type = T_THUMB2_IMM12;
d->instr_flag_type = T_THUMB2_U_FLAG;
return I_LDR; // literal
}
else if(op1 == 1 && Rn != b1111) {
d->instr_imm_type = T_THUMB2_IMM12;
return I_LDR; // immediate
}
else if(op1 == 0 && Rn != b1111) {
if(op2 == 0) { d->instr_type = T_THUMB2_RN_RM_RT_REG;
d->instr_imm_type = T_THUMB2_IMM2;