1/*****************************************************************************/
2/* */
3/* codeseg.c */
4/* */
5/* Code segment structure */
6/* */
7/* */
8/* */
9/* (C) 2001-2011, Ullrich von Bassewitz */
10/* Roemerstrasse 52 */
11/* D-70794 Filderstadt */
12/* EMail: uz@cc65.org */
13/* */
14/* */
15/* This software is provided 'as-is', without any expressed or implied */
16/* warranty. In no event will the authors be held liable for any damages */
17/* arising from the use of this software. */
18/* */
19/* Permission is granted to anyone to use this software for any purpose, */
20/* including commercial applications, and to alter it and redistribute it */
21/* freely, subject to the following restrictions: */
22/* */
23/* 1. The origin of this software must not be misrepresented; you must not */
24/* claim that you wrote the original software. If you use this software */
25/* in a product, an acknowledgment in the product documentation would be */
26/* appreciated but is not required. */
27/* 2. Altered source versions must be plainly marked as such, and must not */
28/* be misrepresented as being the original software. */
29/* 3. This notice may not be removed or altered from any source */
30/* distribution. */
31/* */
32/*****************************************************************************/
33
34
35
36#include <string.h>
37#include <ctype.h>
38
39/* common */
40#include "chartype.h"
41#include "check.h"
42#include "debugflag.h"
43#include "global.h"
44#include "hashfunc.h"
45#include "strbuf.h"
46#include "strutil.h"
47#include "xmalloc.h"
48
49/* cc65 */
50#include "asmlabel.h"
51#include "codeent.h"
52#include "codeinfo.h"
53#include "codeseg.h"
54#include "datatype.h"
55#include "error.h"
56#include "global.h"
57#include "ident.h"
58#include "output.h"
59#include "symentry.h"
60
61
62
63/*****************************************************************************/
64/* Helper functions */
65/*****************************************************************************/
66
67
68
69static void CS_PrintFunctionHeader (const CodeSeg* S)
70/* Print a comment with the function signature to the output file */
71{
72 /* Get the associated function */
73 const SymEntry* Func = S->Func;
74
75 /* If this is a global code segment, do nothing */
76 if (Func) {
77 WriteOutput ("; ---------------------------------------------------------------\n"
78 "; ");
79 PrintFuncSig (OutputFile, Func->Name, Func->Type);
80 WriteOutput ("\n"
81 "; ---------------------------------------------------------------\n"
82 "\n");
83 }
84}
85
86
87
88static void CS_MoveLabelsToEntry (CodeSeg* S, CodeEntry* E)
89/* Move all labels from the label pool to the given entry and remove them
90** from the pool.
91*/
92{
93 /* Transfer the labels if we have any */
94 unsigned I;
95 unsigned LabelCount = CollCount (&S->Labels);
96 for (I = 0; I < LabelCount; ++I) {
97
98 /* Get the label */
99 CodeLabel* L = CollAt (&S->Labels, I);
100
101 /* Attach it to the entry */
102 CE_AttachLabel (E, L);
103 }
104
105 /* Delete the transfered labels */
106 CollDeleteAll (&S->Labels);
107}
108
109
110
111static void CS_MoveLabelsToPool (CodeSeg* S, CodeEntry* E)
112/* Move the labels of the code entry E to the label pool of the code segment */
113{
114 unsigned LabelCount = CE_GetLabelCount (E);
115 while (LabelCount--) {
116 CodeLabel* L = CE_GetLabel (E, LabelCount);
117 L->Owner = 0;
118 CollAppend (&S->Labels, L);
119 }
120 CollDeleteAll (&E->Labels);
121}
122
123
124
125static CodeLabel* CS_FindLabel (CodeSeg* S, const char* Name, unsigned Hash)
126/* Find the label with the given name. Return the label or NULL if not found */
127{
128 /* Get the first hash chain entry */
129 CodeLabel* L = S->LabelHash[Hash];
130
131 /* Search the list */
132 while (L) {
133 if (strcmp (Name, L->Name) == 0) {
134 /* Found */
135 break;
136 }
137 L = L->Next;
138 }
139 return L;
140}
141
142
143
144static CodeLabel* CS_NewCodeLabel (CodeSeg* S, const char* Name, unsigned Hash)
145/* Create a new label and insert it into the label hash table */
146{
147 /* Create a new label */
148 CodeLabel* L = NewCodeLabel (Name, Hash);
149
150 /* Enter the label into the hash table */
151 L->Next = S->LabelHash[L->Hash];
152 S->LabelHash[L->Hash] = L;
153
154 /* Return the new label */
155 return L;
156}
157
158
159
160static void CS_RemoveLabelFromHash (CodeSeg* S, CodeLabel* L)
161/* Remove the given code label from the hash list */
162{
163 /* Get the first entry in the hash chain */
164 CodeLabel* List = S->LabelHash[L->Hash];
165 CHECK (List != 0);
166
167 /* First, remove the label from the hash chain */
168 if (List == L) {
169 /* First entry in hash chain */
170 S->LabelHash[L->Hash] = L->Next;
171 } else {
172 /* Must search through the chain */
173 while (List->Next != L) {
174 /* If we've reached the end of the chain, something is *really* wrong */
175 CHECK (List->Next != 0);
176 /* Next entry */
177 List = List->Next;
178 }
179 /* The next entry is the one, we have been searching for */
180 List->Next = L->Next;
181 }
182}
183
184
185
186/*****************************************************************************/
187/* Functions for parsing instructions */
188/*****************************************************************************/
189
190
191
192static const char* SkipSpace (const char* S)
193/* Skip white space and return an updated pointer */
194{
195 while (IsSpace (*S)) {
196 ++S;
197 }
198 return S;
199}
200
201
202
203static const char* ReadToken (const char* L, const char* Term,
204 char* Buf, unsigned BufSize)
205/* Read the next token into Buf, return the updated line pointer. The
206** token is terminated by one of the characters given in term.
207*/
208{
209 /* Read/copy the token */
210 unsigned I = 0;
211 unsigned ParenCount = 0;
212 while (*L && (ParenCount > 0 || strchr (Term, *L) == 0)) {
213 if (I < BufSize-1) {
214 Buf[I] = *L;
215 } else if (I == BufSize-1) {
216 /* Cannot store this character, this is an input error (maybe
217 ** identifier too long or similar).
218 */
219 Error ("ASM code error: syntax error");
220 }
221 ++I;
222 if (*L == ')') {
223 --ParenCount;
224 } else if (*L == '(') {
225 ++ParenCount;
226 }
227 ++L;
228 }
229
230 /* Terminate the buffer contents */
231 Buf[I] = '\0';
232
233 /* Return the updated line pointer */
234 return L;
235}
236
237
238
239static CodeEntry* ParseInsn (CodeSeg* S, LineInfo* LI, const char* L)
240/* Parse an instruction nnd generate a code entry from it. If the line contains
241** errors, output an error message and return NULL.
242** For simplicity, we don't accept the broad range of input a "real" assembler
243** does. The instruction and the argument are expected to be separated by
244** white space, for example.
245*/
246{
247 char Mnemo[IDENTSIZE+10];
248 const OPCDesc* OPC;
249 am_t AM = 0; /* Initialize to keep gcc silent */
250 char Arg[IDENTSIZE+10];
251 char Reg;
252 CodeEntry* E;
253 CodeLabel* Label;
254
255 /* Read the first token and skip white space after it */
256 L = SkipSpace (ReadToken (L, " \t:", Mnemo, sizeof (Mnemo)));
257
258 /* Check if we have a label */
259 if (*L == ':') {
260
261 /* Skip the colon and following white space */
262 L = SkipSpace (L+1);
263
264 /* Add the label */
265 CS_AddLabel (S, Mnemo);
266
267 /* If we have reached end of line, bail out, otherwise a mnemonic
268 ** may follow.
269 */
270 if (*L == '\0') {
271 return 0;
272 }
273
274 L = SkipSpace (ReadToken (L, " \t", Mnemo, sizeof (Mnemo)));
275 }
276
277 /* Try to find the opcode description for the mnemonic */
278 OPC = FindOP65 (Mnemo);
279
280 /* If we didn't find the opcode, print an error and bail out */
281 if (OPC == 0) {
282 Error ("ASM code error: %s is not a valid mnemonic", Mnemo);
283 return 0;
284 }
285
286 /* Get the addressing mode */
287 Arg[0] = '\0';
288 switch (*L) {
289
290 case '\0':
291 /* Implicit or accu */
292 if (OPC->Info & OF_NOIMP) {
293 AM = AM65_ACC;
294 } else {
295 AM = AM65_IMP;
296 }
297 break;
298
299 case '#':
300 /* Immidiate */
301 StrCopy (Arg, sizeof (Arg), L+1);
302 AM = AM65_IMM;
303 break;
304
305 case '(':
306 /* Indirect */
307 L = ReadToken (L+1, ",)", Arg, sizeof (Arg));
308
309 /* Check for errors */
310 if (*L == '\0') {
311 Error ("ASM code error: syntax error");
312 return 0;
313 }
314
315 /* Check the different indirect modes */
316 if (*L == ',') {
317 /* Expect zp x indirect */
318 L = SkipSpace (L+1);
319 if (toupper (*L) != 'X') {
320 Error ("ASM code error: 'X' expected");
321 return 0;
322 }
323 L = SkipSpace (L+1);
324 if (*L != ')') {
325 Error ("ASM code error: ')' expected");
326 return 0;
327 }
328 L = SkipSpace (L+1);
329 if (*L != '\0') {
330 Error ("ASM code error: syntax error");
331 return 0;
332 }
333 AM = AM65_ZPX_IND;
334 } else if (*L == ')') {
335 /* zp indirect or zp indirect, y */
336 L = SkipSpace (L+1);
337 if (*L == ',') {
338 L = SkipSpace (L+1);
339 if (toupper (*L) != 'Y') {
340 Error ("ASM code error: 'Y' expected");
341 return 0;
342 }
343 L = SkipSpace (L+1);
344 if (*L != '\0') {
345 Error ("ASM code error: syntax error");
346 return 0;
347 }
348 AM = AM65_ZP_INDY;
349 } else if (*L == '\0') {
350 AM = AM65_ZP_IND;
351 } else {
352 Error ("ASM code error: syntax error");
353 return 0;
354 }
355 }
356 break;
357
358 case 'a':
359 case 'A':
360 /* Accumulator? */
361 if (L[1] == '\0') {
362 AM = AM65_ACC;
363 break;
364 }
365 /* FALLTHROUGH */
366
367 default:
368 /* Absolute, maybe indexed */
369 L = ReadToken (L, ",", Arg, sizeof (Arg));
370 if (*L == '\0') {
371 /* Absolute, zeropage or branch */
372 if ((OPC->Info & OF_BRA) != 0) {
373 /* Branch */
374 AM = AM65_BRA;
375 } else if (GetZPInfo(Arg) != 0) {
376 AM = AM65_ZP;
377 } else {
378 /* Check for subroutine call to local label */
379 if ((OPC->Info & OF_CALL) && IsLocalLabelName (Arg)) {
380 Error ("ASM code error: "
381 "Cannot use local label '%s' in subroutine call",
382 Arg);
383 }
384 AM = AM65_ABS;
385 }
386 } else if (*L == ',') {
387 /* Indexed */
388 L = SkipSpace (L+1);
389 if (*L == '\0') {
390 Error ("ASM code error: syntax error");
391 return 0;
392 } else {
393 Reg = toupper (*L);
394 L = SkipSpace (L+1);
395 if (Reg == 'X') {
396 if (GetZPInfo(Arg) != 0) {
397 AM = AM65_ZPX;
398 } else {
399 AM = AM65_ABSX;
400 }
401 } else if (Reg == 'Y') {
402 AM = AM65_ABSY;
403 } else {
404 Error ("ASM code error: syntax error");
405 return 0;
406 }
407 if (*L != '\0') {
408 Error ("ASM code error: syntax error");
409 return 0;
410 }
411 }
412 }
413 break;
414
415 }
416
417 /* If the instruction is a branch, check for the label and generate it
418 ** if it does not exist. This may lead to unused labels (if the label
419 ** is actually an external one) which are removed by the CS_MergeLabels
420 ** function later.
421 */
422 Label = 0;
423 if (AM == AM65_BRA) {
424
425 /* Generate the hash over the label, then search for the label */
426 unsigned Hash = HashStr (Arg) % CS_LABEL_HASH_SIZE;
427 Label = CS_FindLabel (S, Arg, Hash);
428
429 /* If we don't have the label, it's a forward ref - create it unless
430 ** it's an external function.
431 */
432 if (Label == 0 && (OPC->OPC != OP65_JMP || IsLocalLabelName (Arg)) ) {
433 /* Generate a new label */
434 Label = CS_NewCodeLabel (S, Arg, Hash);
435 }
436 }
437
438 /* We do now have the addressing mode in AM. Allocate a new CodeEntry
439 ** structure and initialize it.
440 */
441 E = NewCodeEntry (OPC->OPC, AM, Arg, Label, LI);
442
443 /* Return the new code entry */
444 return E;
445}
446
447
448
449/*****************************************************************************/
450/* Code */
451/*****************************************************************************/
452
453
454
455CodeSeg* NewCodeSeg (const char* SegName, SymEntry* Func)
456/* Create a new code segment, initialize and return it */
457{
458 unsigned I;
459 const Type* RetType;
460
461 /* Allocate memory */
462 CodeSeg* S = xmalloc (sizeof (CodeSeg));
463
464 /* Initialize the fields */
465 S->SegName = xstrdup (SegName);
466 S->Func = Func;
467 InitCollection (&S->Entries);
468 InitCollection (&S->Labels);
469 for (I = 0; I < sizeof(S->LabelHash) / sizeof(S->LabelHash[0]); ++I) {
470 S->LabelHash[I] = 0;
471 }
472
473 /* If we have a function given, get the return type of the function.
474 ** Assume ANY return type besides void will use the A and X registers.
475 */
476 if (S->Func && !IsTypeVoid ((RetType = GetFuncReturn (Func->Type)))) {
477 if (SizeOf (RetType) == SizeOf (type_long)) {
478 S->ExitRegs = REG_EAX;
479 } else {
480 S->ExitRegs = REG_AX;
481 }
482 } else {
483 S->ExitRegs = REG_NONE;
484 }
485
486 /* Copy the global optimization settings */
487 S->Optimize = (unsigned char) IS_Get (&Optimize);
488 S->CodeSizeFactor = (unsigned) IS_Get (&CodeSizeFactor);
489
490 /* Return the new struct */
491 return S;
492}
493
494
495
496void CS_AddEntry (CodeSeg* S, struct CodeEntry* E)
497/* Add an entry to the given code segment */
498{
499 /* Transfer the labels if we have any */
500 CS_MoveLabelsToEntry (S, E);
501
502 /* Add the entry to the list of code entries in this segment */
503 CollAppend (&S->Entries, E);
504}
505
506
507
508void CS_AddVLine (CodeSeg* S, LineInfo* LI, const char* Format, va_list ap)
509/* Add a line to the given code segment */
510{
511 const char* L;
512 CodeEntry* E;
513 char Token[IDENTSIZE+10];
514
515 /* Format the line */
516 StrBuf Buf = STATIC_STRBUF_INITIALIZER;
517 SB_VPrintf (&Buf, Format, ap);
518
519 /* Skip whitespace */
520 L = SkipSpace (SB_GetConstBuf (&Buf));
521
522 /* Check which type of instruction we have */
523 E = 0; /* Assume no insn created */
524 switch (*L) {
525
526 case '\0':
527 /* Empty line, just ignore it */
528 break;
529
530 case ';':
531 /* Comment or hint, ignore it for now */
532 break;
533
534 case '.':
535 /* Control instruction */
536 ReadToken (L, " \t", Token, sizeof (Token));
537 Error ("ASM code error: Pseudo instruction '%s' not supported", Token);
538 break;
539
540 default:
541 E = ParseInsn (S, LI, L);
542 break;
543 }
544
545 /* If we have a code entry, transfer the labels and insert it */
546 if (E) {
547 CS_AddEntry (S, E);
548 }
549
550 /* Cleanup the string buffer */
551 SB_Done (&Buf);
552}
553
554
555
556void CS_AddLine (CodeSeg* S, LineInfo* LI, const char* Format, ...)
557/* Add a line to the given code segment */
558{
559 va_list ap;
560 va_start (ap, Format);
561 CS_AddVLine (S, LI, Format, ap);
562 va_end (ap);
563}
564
565
566
567void CS_InsertEntry (CodeSeg* S, struct CodeEntry* E, unsigned Index)
568/* Insert the code entry at the index given. Following code entries will be
569** moved to slots with higher indices.
570*/
571{
572 /* Insert the entry into the collection */
573 CollInsert (&S->Entries, E, Index);
574}
575
576
577
578void CS_DelEntry (CodeSeg* S, unsigned Index)
579/* Delete an entry from the code segment. This includes moving any associated
580** labels, removing references to labels and even removing the referenced labels
581** if the reference count drops to zero.
582** Note: Labels are moved forward if possible, that is, they are moved to the
583** next insn (not the preceeding one).
584*/
585{
586 /* Get the code entry for the given index */
587 CodeEntry* E = CS_GetEntry (S, Index);
588
589 /* If the entry has a labels, we have to move this label to the next insn.
590 ** If there is no next insn, move the label into the code segement label
591 ** pool. The operation is further complicated by the fact that the next
592 ** insn may already have a label. In that case change all reference to
593 ** this label and delete the label instead of moving it.
594 */
595 unsigned Count = CE_GetLabelCount (E);
596 if (Count > 0) {
597
598 /* The instruction has labels attached. Check if there is a next
599 ** instruction.
600 */
601 if (Index == CS_GetEntryCount (S)-1) {
602
603 /* No next instruction, move to the codeseg label pool */
604 CS_MoveLabelsToPool (S, E);
605
606 } else {
607
608 /* There is a next insn, get it */
609 CodeEntry* N = CS_GetEntry (S, Index+1);
610
611 /* Move labels to the next entry */
612 CS_MoveLabels (S, E, N);
613
614 }
615 }
616
617 /* If this insn references a label, remove the reference. And, if the
618 ** the reference count for this label drops to zero, remove this label.
619 */
620 if (E->JumpTo) {
621 /* Remove the reference */
622 CS_RemoveLabelRef (S, E);
623 }
624
625 /* Delete the pointer to the insn */
626 CollDelete (&S->Entries, Index);
627
628 /* Delete the instruction itself */
629 FreeCodeEntry (E);
630}
631
632
633
634void CS_DelEntries (CodeSeg* S, unsigned Start, unsigned Count)
635/* Delete a range of code entries. This includes removing references to labels,
636** labels attached to the entries and so on.
637*/
638{
639 /* Start deleting the entries from the rear, because this involves less
640 ** memory moving.
641 */
642 while (Count--) {
643 CS_DelEntry (S, Start + Count);
644 }
645}
646
647
648
649void CS_MoveEntries (CodeSeg* S, unsigned Start, unsigned Count, unsigned NewPos)
650/* Move a range of entries from one position to another. Start is the index
651** of the first entry to move, Count is the number of entries and NewPos is
652** the index of the target entry. The entry with the index Start will later
653** have the index NewPos. All entries with indices NewPos and above are
654** moved to higher indices. If the code block is moved to the end of the
655** current code, and if pending labels exist, these labels will get attached
656** to the first instruction of the moved block (the first one after the
657** current code end)
658*/
659{
660 /* Transparently handle an empty range */
661 if (Count == 0) {
662 return;
663 }
664
665 /* If NewPos is at the end of the code segment, move any labels from the
666 ** label pool to the first instruction of the moved range.
667 */
668 if (NewPos == CS_GetEntryCount (S)) {
669 CS_MoveLabelsToEntry (S, CS_GetEntry (S, Start));
670 }
671
672 /* Move the code block to the destination */
673 CollMoveMultiple (&S->Entries, Start, Count, NewPos);
674}
675
676
677
678struct CodeEntry* CS_GetPrevEntry (CodeSeg* S, unsigned Index)
679/* Get the code entry preceeding the one with the index Index. If there is no
680** preceeding code entry, return NULL.
681*/
682{
683 if (Index == 0) {
684 /* This is the first entry */
685 return 0;
686 } else {
687 /* Previous entry available */
688 return CollAtUnchecked (&S->Entries, Index-1);
689 }
690}
691
692
693
694struct CodeEntry* CS_GetNextEntry (CodeSeg* S, unsigned Index)
695/* Get the code entry following the one with the index Index. If there is no
696** following code entry, return NULL.
697*/
698{
699 if (Index >= CollCount (&S->Entries)-1) {
700 /* This is the last entry */
701 return 0;
702 } else {
703 /* Code entries left */
704 return CollAtUnchecked (&S->Entries, Index+1);
705 }
706}
707
708
709
710int CS_GetEntries (CodeSeg* S, struct CodeEntry** List,
711 unsigned Start, unsigned Count)
712/* Get Count code entries into List starting at index start. Return true if
713** we got the lines, return false if not enough lines were available.
714*/
715{
716 /* Check if enough entries are available */
717 if (Start + Count > CollCount (&S->Entries)) {
718 return 0;
719 }
720
721 /* Copy the entries */
722 while (Count--) {
723 *List++ = CollAtUnchecked (&S->Entries, Start++);
724 }
725
726 /* We have the entries */
727 return 1;
728}
729
730
731
732unsigned CS_GetEntryIndex (CodeSeg* S, struct CodeEntry* E)
733/* Return the index of a code entry */
734{
735 int Index = CollIndex (&S->Entries, E);
736 CHECK (Index >= 0);
737 return Index;
738}
739
740
741
742int CS_RangeHasLabel (CodeSeg* S, unsigned Start, unsigned Count)
743/* Return true if any of the code entries in the given range has a label
744** attached. If the code segment does not span the given range, check the
745** possible span instead.
746*/
747{
748 unsigned EntryCount = CS_GetEntryCount(S);
749
750 /* Adjust count. We expect at least Start to be valid. */
751 CHECK (Start < EntryCount);
752 if (Start + Count > EntryCount) {
753 Count = EntryCount - Start;
754 }
755
756 /* Check each entry. Since we have validated the index above, we may
757 ** use the unchecked access function in the loop which is faster.
758 */
759 while (Count--) {
760 const CodeEntry* E = CollAtUnchecked (&S->Entries, Start++);
761 if (CE_HasLabel (E)) {
762 return 1;
763 }
764 }
765
766 /* No label in the complete range */
767 return 0;
768}
769
770
771
772CodeLabel* CS_AddLabel (CodeSeg* S, const char* Name)
773/* Add a code label for the next instruction to follow */
774{
775 /* Calculate the hash from the name */
776 unsigned Hash = HashStr (Name) % CS_LABEL_HASH_SIZE;
777
778 /* Try to find the code label if it does already exist */
779 CodeLabel* L = CS_FindLabel (S, Name, Hash);
780
781 /* Did we find it? */
782 if (L) {
783 /* We found it - be sure it does not already have an owner */
784 if (L->Owner) {
785 Error ("ASM label '%s' is already defined", Name);
786 return L;
787 }
788 } else {
789 /* Not found - create a new one */
790 L = CS_NewCodeLabel (S, Name, Hash);
791 }
792
793 /* Safety. This call is quite costly, but safety is better */
794 if (CollIndex (&S->Labels, L) >= 0) {
795 Error ("ASM label '%s' is already defined", Name);
796 return L;
797 }
798
799 /* We do now have a valid label. Remember it for later */
800 CollAppend (&S->Labels, L);
801
802 /* Return the label */
803 return L;
804}
805
806
807
808CodeLabel* CS_GenLabel (CodeSeg* S, struct CodeEntry* E)
809/* If the code entry E does already have a label, return it. Otherwise
810** create a new label, attach it to E and return it.
811*/
812{
813 CodeLabel* L;
814
815 if (CE_HasLabel (E)) {
816
817 /* Get the label from this entry */
818 L = CE_GetLabel (E, 0);
819
820 } else {
821
822 /* Get a new name */
823 const char* Name = LocalLabelName (GetLocalLabel ());
824
825 /* Generate the hash over the name */
826 unsigned Hash = HashStr (Name) % CS_LABEL_HASH_SIZE;
827
828 /* Create a new label */
829 L = CS_NewCodeLabel (S, Name, Hash);
830
831 /* Attach this label to the code entry */
832 CE_AttachLabel (E, L);
833
834 }
835
836 /* Return the label */
837 return L;
838}
839
840
841
842void CS_DelLabel (CodeSeg* S, CodeLabel* L)
843/* Remove references from this label and delete it. */
844{
845 unsigned Count, I;
846
847 /* First, remove the label from the hash chain */
848 CS_RemoveLabelFromHash (S, L);
849
850 /* Remove references from insns jumping to this label */
851 Count = CollCount (&L->JumpFrom);
852 for (I = 0; I < Count; ++I) {
853 /* Get the insn referencing this label */
854 CodeEntry* E = CollAt (&L->JumpFrom, I);
855 /* Remove the reference */
856 CE_ClearJumpTo (E);
857 }
858 CollDeleteAll (&L->JumpFrom);
859
860 /* Remove the reference to the owning instruction if it has one. The
861 ** function may be called for a label without an owner when deleting
862 ** unfinished parts of the code. This is unfortunate since it allows
863 ** errors to slip through.
864 */
865 if (L->Owner) {
866 CollDeleteItem (&L->Owner->Labels, L);
867 }
868
869 /* All references removed, delete the label itself */
870 FreeCodeLabel (L);
871}
872
873
874
875void CS_MergeLabels (CodeSeg* S)
876/* Merge code labels. That means: For each instruction, remove all labels but
877** one and adjust references accordingly.
878*/
879{
880 unsigned I;
881 unsigned J;
882
883 /* First, remove all labels from the label symbol table that don't have an
884 ** owner (this means that they are actually external labels but we didn't
885 ** know that previously since they may have also been forward references).
886 */
887 for (I = 0; I < CS_LABEL_HASH_SIZE; ++I) {
888
889 /* Get the first label in this hash chain */
890 CodeLabel** L = &S->LabelHash[I];
891 while (*L) {
892 if ((*L)->Owner == 0) {
893
894 /* The label does not have an owner, remove it from the chain */
895 CodeLabel* X = *L;
896 *L = X->Next;
897
898 /* Cleanup any entries jumping to this label */
899 for (J = 0; J < CL_GetRefCount (X); ++J) {
900 /* Get the entry referencing this label */
901 CodeEntry* E = CL_GetRef (X, J);
902 /* And remove the reference. Do NOT call CE_ClearJumpTo
903 ** here, because this will also clear the label name,
904 ** which is not what we want.
905 */
906 E->JumpTo = 0;
907 }
908
909 /* Print some debugging output */
910 if (Debug) {
911 printf ("Removing unused global label '%s'", X->Name);
912 }
913
914 /* And free the label */
915 FreeCodeLabel (X);
916 } else {
917 /* Label is owned, point to next code label pointer */
918 L = &((*L)->Next);
919 }
920 }
921 }
922
923 /* Walk over all code entries */
924 for (I = 0; I < CS_GetEntryCount (S); ++I) {
925
926 CodeLabel* RefLab;
927 unsigned J;
928
929 /* Get a pointer to the next entry */
930 CodeEntry* E = CS_GetEntry (S, I);
931
932 /* If this entry has zero labels, continue with the next one */
933 unsigned LabelCount = CE_GetLabelCount (E);
934 if (LabelCount == 0) {
935 continue;
936 }
937
938 /* We have at least one label. Use the first one as reference label. */
939 RefLab = CE_GetLabel (E, 0);
940
941 /* Walk through the remaining labels and change references to these
942 ** labels to a reference to the one and only label. Delete the labels
943 ** that are no longer used. To increase performance, walk backwards
944 ** through the list.
945 */
946 for (J = LabelCount-1; J >= 1; --J) {
947
948 /* Get the next label */
949 CodeLabel* L = CE_GetLabel (E, J);
950
951 /* Move all references from this label to the reference label */
952 CL_MoveRefs (L, RefLab);
953
954 /* Remove the label completely. */
955 CS_DelLabel (S, L);
956 }
957
958 /* The reference label is the only remaining label. Check if there
959 ** are any references to this label, and delete it if this is not
960 ** the case.
961 */
962 if (CollCount (&RefLab->JumpFrom) == 0) {
963 /* Delete the label */
964 CS_DelLabel (S, RefLab);
965 }
966 }
967}
968
969
970
971void CS_MoveLabels (CodeSeg* S, struct CodeEntry* Old, struct CodeEntry* New)
972/* Move all labels from Old to New. The routine will move the labels itself
973** if New does not have any labels, and move references if there is at least
974** a label for new. If references are moved, the old label is deleted
975** afterwards.
976*/
977{
978 /* Get the number of labels to move */
979 unsigned OldLabelCount = CE_GetLabelCount (Old);
980
981 /* Does the new entry have itself a label? */
982 if (CE_HasLabel (New)) {
983
984 /* The new entry does already have a label - move references */
985 CodeLabel* NewLabel = CE_GetLabel (New, 0);
986 while (OldLabelCount--) {
987
988 /* Get the next label */
989 CodeLabel* OldLabel = CE_GetLabel (Old, OldLabelCount);
990
991 /* Move references */
992 CL_MoveRefs (OldLabel, NewLabel);
993
994 /* Delete the label */
995 CS_DelLabel (S, OldLabel);
996
997 }
998
999 } else {
1000
1001 /* The new entry does not have a label, just move them */
1002 while (OldLabelCount--) {
1003
1004 /* Move the label to the new entry */
1005 CE_MoveLabel (CE_GetLabel (Old, OldLabelCount), New);
1006
1007 }
1008
1009 }
1010}
1011
1012
1013
1014void CS_RemoveLabelRef (CodeSeg* S, struct CodeEntry* E)
1015/* Remove the reference between E and the label it jumps to. The reference
1016** will be removed on both sides and E->JumpTo will be 0 after that. If
1017** the reference was the only one for the label, the label will get
1018** deleted.
1019*/
1020{
1021 /* Get a pointer to the label and make sure it exists */
1022 CodeLabel* L = E->JumpTo;
1023 CHECK (L != 0);
1024
1025 /* Delete the entry from the label */
1026 CollDeleteItem (&L->JumpFrom, E);
1027
1028 /* The entry jumps no longer to L */
1029 CE_ClearJumpTo (E);
1030
1031 /* If there are no more references, delete the label */
1032 if (CollCount (&L->JumpFrom) == 0) {
1033 CS_DelLabel (S, L);
1034 }
1035}
1036
1037
1038
1039void CS_MoveLabelRef (CodeSeg* S, struct CodeEntry* E, CodeLabel* L)
1040/* Change the reference of E to L instead of the current one. If this
1041** was the only reference to the old label, the old label will get
1042** deleted.
1043*/
1044{
1045 /* Get the old label */
1046 CodeLabel* OldLabel = E->JumpTo;
1047
1048 /* Be sure that code entry references a label */
1049 PRECONDITION (OldLabel != 0);
1050
1051 /* Remove the reference to our label */
1052 CS_RemoveLabelRef (S, E);
1053
1054 /* Use the new label */
1055 CL_AddRef (L, E);
1056}
1057
1058
1059
1060void CS_DelCodeRange (CodeSeg* S, unsigned First, unsigned Last)
1061/* Delete all entries between first and last, both inclusive. The function
1062** can only handle basic blocks (First is the only entry, Last the only exit)
1063** and no open labels. It will call FAIL if any of these preconditions are
1064** violated.
1065*/
1066{
1067 unsigned I;
1068 CodeEntry* FirstEntry;
1069
1070 /* Do some sanity checks */
1071 CHECK (First <= Last && Last < CS_GetEntryCount (S));
1072
1073 /* If Last is actually the last insn, call CS_DelCodeAfter instead, which
1074 ** is more flexible in this case.
1075 */
1076 if (Last == CS_GetEntryCount (S) - 1) {
1077 CS_DelCodeAfter (S, First);
1078 return;
1079 }
1080
1081 /* Get the first entry and check if it has any labels. If it has, move
1082 ** them to the insn following Last. If Last is the last insn of the code
1083 ** segment, make them ownerless and move them to the label pool.
1084 */
1085 FirstEntry = CS_GetEntry (S, First);
1086 if (CE_HasLabel (FirstEntry)) {
1087 /* Get the entry following last */
1088 CodeEntry* FollowingEntry = CS_GetNextEntry (S, Last);
1089 if (FollowingEntry) {
1090 /* There is an entry after Last - move the labels */
1091 CS_MoveLabels (S, FirstEntry, FollowingEntry);
1092 } else {
1093 /* Move the labels to the pool and clear the owner pointer */
1094 CS_MoveLabelsToPool (S, FirstEntry);
1095 }
1096 }
1097
1098 /* First pass: Delete all references to labels. If the reference count
1099 ** for a label drops to zero, delete it.
1100 */
1101 for (I = Last; I >= First; --I) {
1102
1103 /* Get the next entry */
1104 CodeEntry* E = CS_GetEntry (S, I);
1105
1106 /* Check if this entry has a label reference */
1107 if (E->JumpTo) {
1108
1109 /* If the label is a label in the label pool, this is an error */
1110 CodeLabel* L = E->JumpTo;
1111 CHECK (CollIndex (&S->Labels, L) < 0);
1112
1113 /* Remove the reference to the label */
1114 CS_RemoveLabelRef (S, E);
1115 }
1116 }
1117
1118 /* Second pass: Delete the instructions. If a label attached to an
1119 ** instruction still has references, it must be references from outside
1120 ** the deleted area, which is an error.
1121 */
1122 for (I = Last; I >= First; --I) {
1123
1124 /* Get the next entry */
1125 CodeEntry* E = CS_GetEntry (S, I);
1126
1127 /* Check if this entry has a label attached */
1128 CHECK (!CE_HasLabel (E));
1129
1130 /* Delete the pointer to the entry */
1131 CollDelete (&S->Entries, I);
1132
1133 /* Delete the entry itself */
1134 FreeCodeEntry (E);
1135 }
1136}
1137
1138
1139
1140void CS_DelCodeAfter (CodeSeg* S, unsigned Last)
1141/* Delete all entries including the given one */
1142{
1143 /* Get the number of entries in this segment */
1144 unsigned Count = CS_GetEntryCount (S);
1145
1146 /* First pass: Delete all references to labels. If the reference count
1147 ** for a label drops to zero, delete it.
1148 */
1149 unsigned C = Count;
1150 while (Last < C--) {
1151
1152 /* Get the next entry */
1153 CodeEntry* E = CS_GetEntry (S, C);
1154
1155 /* Check if this entry has a label reference */
1156 if (E->JumpTo) {
1157 /* If the label is a label in the label pool and this is the last
1158 ** reference to the label, remove the label from the pool.
1159 */
1160 CodeLabel* L = E->JumpTo;
1161 int Index = CollIndex (&S->Labels, L);
1162 if (Index >= 0 && CollCount (&L->JumpFrom) == 1) {
1163 /* Delete it from the pool */
1164 CollDelete (&S->Labels, Index);
1165 }
1166
1167 /* Remove the reference to the label */
1168 CS_RemoveLabelRef (S, E);
1169 }
1170
1171 }
1172
1173 /* Second pass: Delete the instructions. If a label attached to an
1174 ** instruction still has references, it must be references from outside
1175 ** the deleted area. Don't delete the label in this case, just make it
1176 ** ownerless and move it to the label pool.
1177 */
1178 C = Count;
1179 while (Last < C--) {
1180
1181 /* Get the next entry */
1182 CodeEntry* E = CS_GetEntry (S, C);
1183
1184 /* Check if this entry has a label attached */
1185 if (CE_HasLabel (E)) {
1186 /* Move the labels to the pool and clear the owner pointer */
1187 CS_MoveLabelsToPool (S, E);
1188 }
1189
1190 /* Delete the pointer to the entry */
1191 CollDelete (&S->Entries, C);
1192
1193 /* Delete the entry itself */
1194 FreeCodeEntry (E);
1195 }
1196}
1197
1198
1199
1200void CS_ResetMarks (CodeSeg* S, unsigned First, unsigned Last)
1201/* Remove all user marks from the entries in the given range */
1202{
1203 while (First <= Last) {
1204 CE_ResetMark (CS_GetEntry (S, First++));
1205 }
1206}
1207
1208
1209
1210int CS_IsBasicBlock (CodeSeg* S, unsigned First, unsigned Last)
1211/* Check if the given code segment range is a basic block. That is, check if
1212** First is the only entrance and Last is the only exit. This means that no
1213** jump/branch inside the block may jump to an insn below First or after(!)
1214** Last, and that no insn may jump into this block from the outside.
1215*/
1216{
1217 unsigned I;
1218
1219 /* Don't accept invalid ranges */
1220 CHECK (First <= Last);
1221
1222 /* First pass: Walk over the range and remove all marks from the entries */
1223 CS_ResetMarks (S, First, Last);
1224
1225 /* Second pass: Walk over the range checking all labels. Note: There may be
1226 ** label on the first insn which is ok.
1227 */
1228 I = First + 1;
1229 while (I <= Last) {
1230
1231 /* Get the next entry */
1232 CodeEntry* E = CS_GetEntry (S, I);
1233
1234 /* Check if this entry has one or more labels, if so, check which
1235 ** entries jump to this label.
1236 */
1237 unsigned LabelCount = CE_GetLabelCount (E);
1238 unsigned LabelIndex;
1239 for (LabelIndex = 0; LabelIndex < LabelCount; ++LabelIndex) {
1240
1241 /* Get this label */
1242 CodeLabel* L = CE_GetLabel (E, LabelIndex);
1243
1244 /* Walk over all entries that jump to this label. Check for each
1245 ** of the entries if it is out of the range.
1246 */
1247 unsigned RefCount = CL_GetRefCount (L);
1248 unsigned RefIndex;
1249 for (RefIndex = 0; RefIndex < RefCount; ++RefIndex) {
1250
1251 /* Get the code entry that jumps here */
1252 CodeEntry* Ref = CL_GetRef (L, RefIndex);
1253
1254 /* Walk over out complete range and check if we find the
1255 ** refering entry. This is cheaper than using CS_GetEntryIndex,
1256 ** because CS_GetEntryIndex will search the complete code
1257 ** segment and not just our range.
1258 */
1259 unsigned J;
1260 for (J = First; J <= Last; ++J) {
1261 if (Ref == CS_GetEntry (S, J)) {
1262 break;
1263 }
1264 }
1265 if (J > Last) {
1266 /* We did not find the entry. This means that the jump to
1267 ** out code segment entry E came from outside the range,
1268 ** which in turn means that the given range is not a basic
1269 ** block.
1270 */
1271 CS_ResetMarks (S, First, Last);
1272 return 0;
1273 }
1274
1275 /* If we come here, we found the entry. Mark it, so we know
1276 ** that the branch to the label is in range.
1277 */
1278 CE_SetMark (Ref);
1279 }
1280 }
1281
1282 /* Next entry */
1283 ++I;
1284 }
1285
1286 /* Third pass: Walk again over the range and check all branches. If we
1287 ** find a branch that is not marked, its target is not inside the range
1288 ** (since we checked all the labels in the range before).
1289 */
1290 I = First;
1291 while (I <= Last) {
1292
1293 /* Get the next entry */
1294 CodeEntry* E = CS_GetEntry (S, I);
1295
1296 /* Check if this is a branch and if so, if it has a mark */
1297 if (E->Info & (OF_UBRA | OF_CBRA)) {
1298 if (!CE_HasMark (E)) {
1299 /* No mark means not a basic block. Before bailing out, be sure
1300 ** to remove the marks from the remaining entries.
1301 */
1302 CS_ResetMarks (S, I+1, Last);
1303 return 0;
1304 }
1305
1306 /* Remove the mark */
1307 CE_ResetMark (E);
1308 }
1309
1310 /* Next entry */
1311 ++I;
1312 }
1313
1314 /* Done - this is a basic block */
1315 return 1;
1316}
1317
1318
1319
1320void CS_OutputPrologue (const CodeSeg* S)
1321/* If the given code segment is a code segment for a function, output the
1322** assembler prologue into the file. That is: Output a comment header, switch
1323** to the correct segment and enter the local function scope. If the code
1324** segment is global, do nothing.
1325*/
1326{
1327 /* Get the function associated with the code segment */
1328 SymEntry* Func = S->Func;
1329
1330 /* If the code segment is associated with a function, print a function
1331 ** header and enter a local scope. Be sure to switch to the correct
1332 ** segment before outputing the function label.
1333 */
1334 if (Func) {
1335 /* Get the function descriptor */
1336 CS_PrintFunctionHeader (S);
1337 WriteOutput (".segment\t\"%s\"\n\n.proc\t_%s", S->SegName, Func->Name);
1338 if (IsQualNear (Func->Type)) {
1339 WriteOutput (": near");
1340 } else if (IsQualFar (Func->Type)) {
1341 WriteOutput (": far");
1342 }
1343 WriteOutput ("\n\n");
1344 }
1345
1346}
1347
1348
1349
1350void CS_OutputEpilogue (const CodeSeg* S)
1351/* If the given code segment is a code segment for a function, output the
1352** assembler epilogue into the file. That is: Close the local function scope.
1353*/
1354{
1355 if (S->Func) {
1356 WriteOutput ("\n.endproc\n\n");
1357 }
1358}
1359
1360
1361
1362void CS_Output (CodeSeg* S)
1363/* Output the code segment data to the output file */
1364{
1365 unsigned I;
1366 const LineInfo* LI;
1367
1368 /* Get the number of entries in this segment */
1369 unsigned Count = CS_GetEntryCount (S);
1370
1371 /* If the code segment is empty, bail out here */
1372 if (Count == 0) {
1373 return;
1374 }
1375
1376 /* Generate register info */
1377 CS_GenRegInfo (S);
1378
1379 /* Output the segment directive */
1380 WriteOutput (".segment\t\"%s\"\n\n", S->SegName);
1381
1382 /* Output all entries, prepended by the line information if it has changed */
1383 LI = 0;
1384 for (I = 0; I < Count; ++I) {
1385 /* Get the next entry */
1386 const CodeEntry* E = CollConstAt (&S->Entries, I);
1387 /* Check if the line info has changed. If so, output the source line
1388 ** if the option is enabled and output debug line info if the debug
1389 ** option is enabled.
1390 */
1391 if (E->LI != LI) {
1392 /* Line info has changed, remember the new line info */
1393 LI = E->LI;
1394
1395 /* Add the source line as a comment. Beware: When line continuation
1396 ** was used, the line may contain newlines.
1397 */
1398 if (AddSource) {
1399 const char* L = LI->Line;
1400 WriteOutput (";\n; ");
1401 while (*L) {
1402 const char* N = strchr (L, '\n');
1403 if (N) {
1404 /* We have a newline, just write the first part */
1405 WriteOutput ("%.*s\n; ", (int) (N - L), L);
1406 L = N+1;
1407 } else {
1408 /* No Newline, write as is */
1409 WriteOutput ("%s\n", L);
1410 break;
1411 }
1412 }
1413 WriteOutput (";\n");
1414 }
1415
1416 /* Add line debug info */
1417 if (DebugInfo) {
1418 WriteOutput ("\t.dbg\tline, \"%s\", %u\n",
1419 GetInputName (LI), GetInputLine (LI));
1420 }
1421 }
1422 /* Output the code */
1423 CE_Output (E);
1424 }
1425
1426 /* If debug info is enabled, terminate the last line number information */
1427 if (DebugInfo) {
1428 WriteOutput ("\t.dbg\tline\n");
1429 }
1430
1431 /* Free register info */
1432 CS_FreeRegInfo (S);
1433}
1434
1435
1436
1437void CS_FreeRegInfo (CodeSeg* S)
1438/* Free register infos for all instructions */
1439{
1440 unsigned I;
1441 for (I = 0; I < CS_GetEntryCount (S); ++I) {
1442 CE_FreeRegInfo (CS_GetEntry(S, I));
1443 }
1444}
1445
1446
1447
1448void CS_GenRegInfo (CodeSeg* S)
1449/* Generate register infos for all instructions */
1450{
1451 unsigned I;
1452 RegContents Regs; /* Initial register contents */
1453 RegContents* CurrentRegs; /* Current register contents */
1454 int WasJump; /* True if last insn was a jump */
1455 int Done; /* All runs done flag */
1456
1457 /* Be sure to delete all register infos */
1458 CS_FreeRegInfo (S);
1459
1460 /* We may need two runs to get back references right */
1461 do {
1462
1463 /* Assume we're done after this run */
1464 Done = 1;
1465
1466 /* On entry, the register contents are unknown */
1467 RC_Invalidate (&Regs);
1468 CurrentRegs = &Regs;
1469
1470 /* Walk over all insns and note just the changes from one insn to the
1471 ** next one.
1472 */
1473 WasJump = 0;
1474 for (I = 0; I < CS_GetEntryCount (S); ++I) {
1475
1476 CodeEntry* P;
1477
1478 /* Get the next instruction */
1479 CodeEntry* E = CollAtUnchecked (&S->Entries, I);
1480
1481 /* If the instruction has a label, we need some special handling */
1482 unsigned LabelCount = CE_GetLabelCount (E);
1483 if (LabelCount > 0) {
1484
1485 /* Loop over all entry points that jump here. If these entry
1486 ** points already have register info, check if all values are
1487 ** known and identical. If all values are identical, and the
1488 ** preceeding instruction was not an unconditional branch, check
1489 ** if the register value on exit of the preceeding instruction
1490 ** is also identical. If all these values are identical, the
1491 ** value of a register is known, otherwise it is unknown.
1492 */
1493 CodeLabel* Label = CE_GetLabel (E, 0);
1494 unsigned Entry;
1495 if (WasJump) {
1496 /* Preceeding insn was an unconditional branch */
1497 CodeEntry* J = CL_GetRef(Label, 0);
1498 if (J->RI) {
1499 Regs = J->RI->Out2;
1500 } else {
1501 RC_Invalidate (&Regs);
1502 }
1503 Entry = 1;
1504 } else {
1505 Regs = *CurrentRegs;
1506 Entry = 0;
1507 }
1508
1509 while (Entry < CL_GetRefCount (Label)) {
1510 /* Get this entry */
1511 CodeEntry* J = CL_GetRef (Label, Entry);
1512 if (J->RI == 0) {
1513 /* No register info for this entry. This means that the
1514 ** instruction that jumps here is at higher addresses and
1515 ** the jump is a backward jump. We need a second run to
1516 ** get the register info right in this case. Until then,
1517 ** assume unknown register contents.
1518 */
1519 Done = 0;
1520 RC_Invalidate (&Regs);
1521 break;
1522 }
1523 if (J->RI->Out2.RegA != Regs.RegA) {
1524 Regs.RegA = UNKNOWN_REGVAL;
1525 }
1526 if (J->RI->Out2.RegX != Regs.RegX) {
1527 Regs.RegX = UNKNOWN_REGVAL;
1528 }
1529 if (J->RI->Out2.RegY != Regs.RegY) {
1530 Regs.RegY = UNKNOWN_REGVAL;
1531 }
1532 if (J->RI->Out2.SRegLo != Regs.SRegLo) {
1533 Regs.SRegLo = UNKNOWN_REGVAL;
1534 }
1535 if (J->RI->Out2.SRegHi != Regs.SRegHi) {
1536 Regs.SRegHi = UNKNOWN_REGVAL;
1537 }
1538 if (J->RI->Out2.Tmp1 != Regs.Tmp1) {
1539 Regs.Tmp1 = UNKNOWN_REGVAL;
1540 }
1541 ++Entry;
1542 }
1543
1544 /* Use this register info */
1545 CurrentRegs = &Regs;
1546
1547 }
1548
1549 /* Generate register info for this instruction */
1550 CE_GenRegInfo (E, CurrentRegs);
1551
1552 /* Remember for the next insn if this insn was an uncondition branch */
1553 WasJump = (E->Info & OF_UBRA) != 0;
1554
1555 /* Output registers for this insn are input for the next */
1556 CurrentRegs = &E->RI->Out;
1557
1558 /* If this insn is a branch on zero flag, we may have more info on
1559 ** register contents for one of both flow directions, but only if
1560 ** there is a previous instruction.
1561 */
1562 if ((E->Info & OF_ZBRA) != 0 && (P = CS_GetPrevEntry (S, I)) != 0) {
1563
1564 /* Get the branch condition */
1565 bc_t BC = GetBranchCond (E->OPC);
1566
1567 /* Check the previous instruction */
1568 switch (P->OPC) {
1569
1570 case OP65_ADC:
1571 case OP65_AND:
1572 case OP65_DEA:
1573 case OP65_EOR:
1574 case OP65_INA:
1575 case OP65_LDA:
1576 case OP65_ORA:
1577 case OP65_PLA:
1578 case OP65_SBC:
1579 /* A is zero in one execution flow direction */
1580 if (BC == BC_EQ) {
1581 E->RI->Out2.RegA = 0;
1582 } else {
1583 E->RI->Out.RegA = 0;
1584 }
1585 break;
1586
1587 case OP65_CMP:
1588 /* If this is an immidiate compare, the A register has
1589 ** the value of the compare later.
1590 */
1591 if (CE_IsConstImm (P)) {
1592 if (BC == BC_EQ) {
1593 E->RI->Out2.RegA = (unsigned char)P->Num;
1594 } else {
1595 E->RI->Out.RegA = (unsigned char)P->Num;
1596 }
1597 }
1598 break;
1599
1600 case OP65_CPX:
1601 /* If this is an immidiate compare, the X register has
1602 ** the value of the compare later.
1603 */
1604 if (CE_IsConstImm (P)) {
1605 if (BC == BC_EQ) {
1606 E->RI->Out2.RegX = (unsigned char)P->Num;
1607 } else {
1608 E->RI->Out.RegX = (unsigned char)P->Num;
1609 }
1610 }
1611 break;
1612
1613 case OP65_CPY:
1614 /* If this is an immidiate compare, the Y register has
1615 ** the value of the compare later.
1616 */
1617 if (CE_IsConstImm (P)) {
1618 if (BC == BC_EQ) {
1619 E->RI->Out2.RegY = (unsigned char)P->Num;
1620 } else {
1621 E->RI->Out.RegY = (unsigned char)P->Num;
1622 }
1623 }
1624 break;
1625
1626 case OP65_DEX:
1627 case OP65_INX:
1628 case OP65_LDX:
1629 case OP65_PLX:
1630 /* X is zero in one execution flow direction */
1631 if (BC == BC_EQ) {
1632 E->RI->Out2.RegX = 0;
1633 } else {
1634 E->RI->Out.RegX = 0;
1635 }
1636 break;
1637
1638 case OP65_DEY:
1639 case OP65_INY:
1640 case OP65_LDY:
1641 case OP65_PLY:
1642 /* X is zero in one execution flow direction */
1643 if (BC == BC_EQ) {
1644 E->RI->Out2.RegY = 0;
1645 } else {
1646 E->RI->Out.RegY = 0;
1647 }
1648 break;
1649
1650 case OP65_TAX:
1651 case OP65_TXA:
1652 /* If the branch is a beq, both A and X are zero at the
1653 ** branch target, otherwise they are zero at the next
1654 ** insn.
1655 */
1656 if (BC == BC_EQ) {
1657 E->RI->Out2.RegA = E->RI->Out2.RegX = 0;
1658 } else {
1659 E->RI->Out.RegA = E->RI->Out.RegX = 0;
1660 }
1661 break;
1662
1663 case OP65_TAY:
1664 case OP65_TYA:
1665 /* If the branch is a beq, both A and Y are zero at the
1666 ** branch target, otherwise they are zero at the next
1667 ** insn.
1668 */
1669 if (BC == BC_EQ) {
1670 E->RI->Out2.RegA = E->RI->Out2.RegY = 0;
1671 } else {
1672 E->RI->Out.RegA = E->RI->Out.RegY = 0;
1673 }
1674 break;
1675
1676 default:
1677 break;
1678
1679 }
1680 }
1681 }
1682 } while (!Done);
1683
1684}
1685