aboutsummaryrefslogtreecommitdiff
path: root/cpu-exec.c
blob: c428b3e381d7d2c59b896e713e5ec8304b8481ae (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
/*
 *  i386 emulator main execution loop
 * 
 *  Copyright (c) 2003 Fabrice Bellard
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include "config.h"
#include "exec.h"
#include "disas.h"

#if !defined(CONFIG_SOFTMMU)
#undef EAX
#undef ECX
#undef EDX
#undef EBX
#undef ESP
#undef EBP
#undef ESI
#undef EDI
#undef EIP
#include <signal.h>
#include <sys/ucontext.h>
#endif

int tb_invalidated_flag;

//#define DEBUG_EXEC
//#define DEBUG_SIGNAL

#if defined(TARGET_ARM) || defined(TARGET_SPARC)
/* XXX: unify with i386 target */
void cpu_loop_exit(void)
{
    longjmp(env->jmp_env, 1);
}
#endif

/* exit the current TB from a signal handler. The host registers are
   restored in a state compatible with the CPU emulator
 */
void cpu_resume_from_signal(CPUState *env1, void *puc) 
{
#if !defined(CONFIG_SOFTMMU)
    struct ucontext *uc = puc;
#endif

    env = env1;

    /* XXX: restore cpu registers saved in host registers */

#if !defined(CONFIG_SOFTMMU)
    if (puc) {
        /* XXX: use siglongjmp ? */
        sigprocmask(SIG_SETMASK, &uc->uc_sigmask, NULL);
    }
#endif
    longjmp(env->jmp_env, 1);
}

/* main execution loop */

int cpu_exec(CPUState *env1)
{
    int saved_T0, saved_T1, saved_T2;
    CPUState *saved_env;
#ifdef reg_EAX
    int saved_EAX;
#endif
#ifdef reg_ECX
    int saved_ECX;
#endif
#ifdef reg_EDX
    int saved_EDX;
#endif
#ifdef reg_EBX
    int saved_EBX;
#endif
#ifdef reg_ESP
    int saved_ESP;
#endif
#ifdef reg_EBP
    int saved_EBP;
#endif
#ifdef reg_ESI
    int saved_ESI;
#endif
#ifdef reg_EDI
    int saved_EDI;
#endif
#ifdef __sparc__
    int saved_i7, tmp_T0;
#endif
    int code_gen_size, ret, interrupt_request;
    void (*gen_func)(void);
    TranslationBlock *tb, **ptb;
    target_ulong cs_base, pc;
    uint8_t *tc_ptr;
    unsigned int flags;

    /* first we save global registers */
    saved_env = env;
    env = env1;
    saved_T0 = T0;
    saved_T1 = T1;
    saved_T2 = T2;
#ifdef __sparc__
    /* we also save i7 because longjmp may not restore it */
    asm volatile ("mov %%i7, %0" : "=r" (saved_i7));
#endif

#if defined(TARGET_I386)
#ifdef reg_EAX
    saved_EAX = EAX;
#endif
#ifdef reg_ECX
    saved_ECX = ECX;
#endif
#ifdef reg_EDX
    saved_EDX = EDX;
#endif
#ifdef reg_EBX
    saved_EBX = EBX;
#endif
#ifdef reg_ESP
    saved_ESP = ESP;
#endif
#ifdef reg_EBP
    saved_EBP = EBP;
#endif
#ifdef reg_ESI
    saved_ESI = ESI;
#endif
#ifdef reg_EDI
    saved_EDI = EDI;
#endif

    env_to_regs();
    /* put eflags in CPU temporary format */
    CC_SRC = env->eflags & (CC_O | CC_S | CC_Z | CC_A | CC_P | CC_C);
    DF = 1 - (2 * ((env->eflags >> 10) & 1));
    CC_OP = CC_OP_EFLAGS;
    env->eflags &= ~(DF_MASK | CC_O | CC_S | CC_Z | CC_A | CC_P | CC_C);
#elif defined(TARGET_ARM)
    {
        unsigned int psr;
        psr = env->cpsr;
        env->CF = (psr >> 29) & 1;
        env->NZF = (psr & 0xc0000000) ^ 0x40000000;
        env->VF = (psr << 3) & 0x80000000;
        env->cpsr = psr & ~0xf0000000;
    }
#elif defined(TARGET_SPARC)
#elif defined(TARGET_PPC)
#else
#error unsupported target CPU
#endif
    env->exception_index = -1;

    /* prepare setjmp context for exception handling */
    for(;;) {
        if (setjmp(env->jmp_env) == 0) {
            env->current_tb = NULL;
            /* if an exception is pending, we execute it here */
            if (env->exception_index >= 0) {
                if (env->exception_index >= EXCP_INTERRUPT) {
                    /* exit request from the cpu execution loop */
                    ret = env->exception_index;
                    break;
                } else if (env->user_mode_only) {
                    /* if user mode only, we simulate a fake exception
                       which will be hanlded outside the cpu execution
                       loop */
#if defined(TARGET_I386)
                    do_interrupt_user(env->exception_index, 
                                      env->exception_is_int, 
                                      env->error_code, 
                                      env->exception_next_eip);
#endif
                    ret = env->exception_index;
                    break;
                } else {
#if defined(TARGET_I386)
                    /* simulate a real cpu exception. On i386, it can
                       trigger new exceptions, but we do not handle
                       double or triple faults yet. */
                    do_interrupt(env->exception_index, 
                                 env->exception_is_int, 
                                 env->error_code, 
                                 env->exception_next_eip, 0);
#elif defined(TARGET_PPC)
                    do_interrupt(env);
#elif defined(TARGET_SPARC)
                    do_interrupt(env->exception_index, 
                                 0,
                                 env->error_code, 
                                 env->exception_next_pc, 0);
#endif
                }
                env->exception_index = -1;
            }
            T0 = 0; /* force lookup of first TB */
            for(;;) {
#ifdef __sparc__
                /* g1 can be modified by some libc? functions */ 
                tmp_T0 = T0;
#endif	    
                interrupt_request = env->interrupt_request;
                if (__builtin_expect(interrupt_request, 0)) {
#if defined(TARGET_I386)
                    /* if hardware interrupt pending, we execute it */
                    if ((interrupt_request & CPU_INTERRUPT_HARD) &&
                        (env->eflags & IF_MASK) && 
                        !(env->hflags & HF_INHIBIT_IRQ_MASK)) {
                        int intno;
                        env->interrupt_request &= ~CPU_INTERRUPT_HARD;
                        intno = cpu_get_pic_interrupt(env);
                        if (loglevel & CPU_LOG_TB_IN_ASM) {
                            fprintf(logfile, "Servicing hardware INT=0x%02x\n", intno);
                        }
                        do_interrupt(intno, 0, 0, 0, 1);
                        /* ensure that no TB jump will be modified as
                           the program flow was changed */
#ifdef __sparc__
                        tmp_T0 = 0;
#else
                        T0 = 0;
#endif
                    }
#elif defined(TARGET_PPC)
#if 0
                    if ((interrupt_request & CPU_INTERRUPT_RESET)) {
                        cpu_ppc_reset(env);
                    }
#endif
                    if (msr_ee != 0) {
                    if ((interrupt_request & CPU_INTERRUPT_HARD)) {
			    /* Raise it */
			    env->exception_index = EXCP_EXTERNAL;
			    env->error_code = 0;
                            do_interrupt(env);
                        env->interrupt_request &= ~CPU_INTERRUPT_HARD;
			} else if ((interrupt_request & CPU_INTERRUPT_TIMER)) {
			    /* Raise it */
			    env->exception_index = EXCP_DECR;
			    env->error_code = 0;
			    do_interrupt(env);
                            env->interrupt_request &= ~CPU_INTERRUPT_TIMER;
			}
                    }
#elif defined(TARGET_SPARC)
                    if (interrupt_request & CPU_INTERRUPT_HARD) {
			do_interrupt(env->interrupt_index, 0, 0, 0, 0);
                        env->interrupt_request &= ~CPU_INTERRUPT_HARD;
		    } else if (interrupt_request & CPU_INTERRUPT_TIMER) {
			//do_interrupt(0, 0, 0, 0, 0);
			env->interrupt_request &= ~CPU_INTERRUPT_TIMER;
		    }
#endif
                    if (interrupt_request & CPU_INTERRUPT_EXITTB) {
                        env->interrupt_request &= ~CPU_INTERRUPT_EXITTB;
                        /* ensure that no TB jump will be modified as
                           the program flow was changed */
#ifdef __sparc__
                        tmp_T0 = 0;
#else
                        T0 = 0;
#endif
                    }
                    if (interrupt_request & CPU_INTERRUPT_EXIT) {
                        env->interrupt_request &= ~CPU_INTERRUPT_EXIT;
                        env->exception_index = EXCP_INTERRUPT;
                        cpu_loop_exit();
                    }
                }
#ifdef DEBUG_EXEC
                if ((loglevel & CPU_LOG_EXEC)) {
#if defined(TARGET_I386)
                    /* restore flags in standard format */
                    env->regs[R_EAX] = EAX;
                    env->regs[R_EBX] = EBX;
                    env->regs[R_ECX] = ECX;
                    env->regs[R_EDX] = EDX;
                    env->regs[R_ESI] = ESI;
                    env->regs[R_EDI] = EDI;
                    env->regs[R_EBP] = EBP;
                    env->regs[R_ESP] = ESP;
                    env->eflags = env->eflags | cc_table[CC_OP].compute_all() | (DF & DF_MASK);
                    cpu_dump_state(env, logfile, fprintf, X86_DUMP_CCOP);
                    env->eflags &= ~(DF_MASK | CC_O | CC_S | CC_Z | CC_A | CC_P | CC_C);
#elif defined(TARGET_ARM)
                    env->cpsr = compute_cpsr();
                    cpu_dump_state(env, logfile, fprintf, 0);
                    env->cpsr &= ~0xf0000000;
#elif defined(TARGET_SPARC)
                    cpu_dump_state (env, logfile, fprintf, 0);
#elif defined(TARGET_PPC)
                    cpu_dump_state(env, logfile, fprintf, 0);
#else
#error unsupported target CPU 
#endif
                }
#endif
                /* we record a subset of the CPU state. It will
                   always be the same before a given translated block
                   is executed. */
#if defined(TARGET_I386)
                flags = env->hflags;
                flags |= (env->eflags & (IOPL_MASK | TF_MASK | VM_MASK));
                cs_base = env->segs[R_CS].base;
                pc = cs_base + env->eip;
#elif defined(TARGET_ARM)
                flags = 0;
                cs_base = 0;
                pc = env->regs[15];
#elif defined(TARGET_SPARC)
                flags = 0;
                cs_base = env->npc;
                pc = env->pc;
#elif defined(TARGET_PPC)
                flags = 0;
                cs_base = 0;
                pc = env->nip;
#else
#error unsupported CPU
#endif
                tb = tb_find(&ptb, pc, cs_base, 
                             flags);
                if (!tb) {
                    TranslationBlock **ptb1;
                    unsigned int h;
                    target_ulong phys_pc, phys_page1, phys_page2, virt_page2;
                    
                    
                    spin_lock(&tb_lock);

                    tb_invalidated_flag = 0;
                    
                    regs_to_env(); /* XXX: do it just before cpu_gen_code() */

                    /* find translated block using physical mappings */
                    phys_pc = get_phys_addr_code(env, pc);
                    phys_page1 = phys_pc & TARGET_PAGE_MASK;
                    phys_page2 = -1;
                    h = tb_phys_hash_func(phys_pc);
                    ptb1 = &tb_phys_hash[h];
                    for(;;) {
                        tb = *ptb1;
                        if (!tb)
                            goto not_found;
                        if (tb->pc == pc && 
                            tb->page_addr[0] == phys_page1 &&
                            tb->cs_base == cs_base && 
                            tb->flags == flags) {
                            /* check next page if needed */
                            if (tb->page_addr[1] != -1) {
                                virt_page2 = (pc & TARGET_PAGE_MASK) + 
                                    TARGET_PAGE_SIZE;
                                phys_page2 = get_phys_addr_code(env, virt_page2);
                                if (tb->page_addr[1] == phys_page2)
                                    goto found;
                            } else {
                                goto found;
                            }
                        }
                        ptb1 = &tb->phys_hash_next;
                    }
                not_found:
                    /* if no translated code available, then translate it now */
                    tb = tb_alloc(pc);
                    if (!tb) {
                        /* flush must be done */
                        tb_flush(env);
                        /* cannot fail at this point */
                        tb = tb_alloc(pc);
                        /* don't forget to invalidate previous TB info */
                        ptb = &tb_hash[tb_hash_func(pc)];
                        T0 = 0;
                    }
                    tc_ptr = code_gen_ptr;
                    tb->tc_ptr = tc_ptr;
                    tb->cs_base = cs_base;
                    tb->flags = flags;
                    cpu_gen_code(env, tb, CODE_GEN_MAX_SIZE, &code_gen_size);
                    code_gen_ptr = (void *)(((unsigned long)code_gen_ptr + code_gen_size + CODE_GEN_ALIGN - 1) & ~(CODE_GEN_ALIGN - 1));
                    
                    /* check next page if needed */
                    virt_page2 = (pc + tb->size - 1) & TARGET_PAGE_MASK;
                    phys_page2 = -1;
                    if ((pc & TARGET_PAGE_MASK) != virt_page2) {
                        phys_page2 = get_phys_addr_code(env, virt_page2);
                    }
                    tb_link_phys(tb, phys_pc, phys_page2);

                found:
                    if (tb_invalidated_flag) {
                        /* as some TB could have been invalidated because
                           of memory exceptions while generating the code, we
                           must recompute the hash index here */
                        ptb = &tb_hash[tb_hash_func(pc)];
                        while (*ptb != NULL)
                            ptb = &(*ptb)->hash_next;
                        T0 = 0;
                    }
                    /* we add the TB in the virtual pc hash table */
                    *ptb = tb;
                    tb->hash_next = NULL;
                    tb_link(tb);
                    spin_unlock(&tb_lock);
                }
#ifdef DEBUG_EXEC
                if ((loglevel & CPU_LOG_EXEC) && (env->hflags & HF_LMA_MASK)) {
                    fprintf(logfile, "Trace 0x%08lx [" TARGET_FMT_lx "] %s\n",
                            (long)tb->tc_ptr, tb->pc,
                            lookup_symbol(tb->pc));
                }
#endif
#ifdef __sparc__
                T0 = tmp_T0;
#endif	    
                /* see if we can patch the calling TB. */
                {
                    if (T0 != 0
#if defined(TARGET_I386) && defined(USE_CODE_COPY)
                    && (tb->cflags & CF_CODE_COPY) == 
                    (((TranslationBlock *)(T0 & ~3))->cflags & CF_CODE_COPY)
#endif
                    ) {
                    spin_lock(&tb_lock);
                    tb_add_jump((TranslationBlock *)(long)(T0 & ~3), T0 & 3, tb);
#if defined(USE_CODE_COPY)
                    /* propagates the FP use info */
                    ((TranslationBlock *)(T0 & ~3))->cflags |= 
                        (tb->cflags & CF_FP_USED);
#endif
                    spin_unlock(&tb_lock);
                }
                }
                tc_ptr = tb->tc_ptr;
                env->current_tb = tb;
                /* execute the generated code */
                gen_func = (void *)tc_ptr;
#if defined(__sparc__)
                __asm__ __volatile__("call	%0\n\t"
                                     "mov	%%o7,%%i0"
                                     : /* no outputs */
                                     : "r" (gen_func) 
                                     : "i0", "i1", "i2", "i3", "i4", "i5");
#elif defined(__arm__)
                asm volatile ("mov pc, %0\n\t"
                              ".global exec_loop\n\t"
                              "exec_loop:\n\t"
                              : /* no outputs */
                              : "r" (gen_func)
                              : "r1", "r2", "r3", "r8", "r9", "r10", "r12", "r14");
#elif defined(TARGET_I386) && defined(USE_CODE_COPY)
{
    if (!(tb->cflags & CF_CODE_COPY)) {
        if ((tb->cflags & CF_FP_USED) && env->native_fp_regs) {
            save_native_fp_state(env);
        }
        gen_func();
    } else {
        if ((tb->cflags & CF_FP_USED) && !env->native_fp_regs) {
            restore_native_fp_state(env);
        }
        /* we work with native eflags */
        CC_SRC = cc_table[CC_OP].compute_all();
        CC_OP = CC_OP_EFLAGS;
        asm(".globl exec_loop\n"
            "\n"
            "debug1:\n"
            "    pushl %%ebp\n"
            "    fs movl %10, %9\n"
            "    fs movl %11, %%eax\n"
            "    andl $0x400, %%eax\n"
            "    fs orl %8, %%eax\n"
            "    pushl %%eax\n"
            "    popf\n"
            "    fs movl %%esp, %12\n"
            "    fs movl %0, %%eax\n"
            "    fs movl %1, %%ecx\n"
            "    fs movl %2, %%edx\n"
            "    fs movl %3, %%ebx\n"
            "    fs movl %4, %%esp\n"
            "    fs movl %5, %%ebp\n"
            "    fs movl %6, %%esi\n"
            "    fs movl %7, %%edi\n"
            "    fs jmp *%9\n"
            "exec_loop:\n"
            "    fs movl %%esp, %4\n"
            "    fs movl %12, %%esp\n"
            "    fs movl %%eax, %0\n"
            "    fs movl %%ecx, %1\n"
            "    fs movl %%edx, %2\n"
            "    fs movl %%ebx, %3\n"
            "    fs movl %%ebp, %5\n"
            "    fs movl %%esi, %6\n"
            "    fs movl %%edi, %7\n"
            "    pushf\n"
            "    popl %%eax\n"
            "    movl %%eax, %%ecx\n"
            "    andl $0x400, %%ecx\n"
            "    shrl $9, %%ecx\n"
            "    andl $0x8d5, %%eax\n"
            "    fs movl %%eax, %8\n"
            "    movl $1, %%eax\n"
            "    subl %%ecx, %%eax\n"
            "    fs movl %%eax, %11\n"
            "    fs movl %9, %%ebx\n" /* get T0 value */
            "    popl %%ebp\n"
            :
            : "m" (*(uint8_t *)offsetof(CPUState, regs[0])),
            "m" (*(uint8_t *)offsetof(CPUState, regs[1])),
            "m" (*(uint8_t *)offsetof(CPUState, regs[2])),
            "m" (*(uint8_t *)offsetof(CPUState, regs[3])),
            "m" (*(uint8_t *)offsetof(CPUState, regs[4])),
            "m" (*(uint8_t *)offsetof(CPUState, regs[5])),
            "m" (*(uint8_t *)offsetof(CPUState, regs[6])),
            "m" (*(uint8_t *)offsetof(CPUState, regs[7])),
            "m" (*(uint8_t *)offsetof(CPUState, cc_src)),
            "m" (*(uint8_t *)offsetof(CPUState, tmp0)),
            "a" (gen_func),
            "m" (*(uint8_t *)offsetof(CPUState, df)),
            "m" (*(uint8_t *)offsetof(CPUState, saved_esp))
            : "%ecx", "%edx"
            );
    }
}
#else
                gen_func();
#endif
                env->current_tb = NULL;
                /* reset soft MMU for next block (it can currently
                   only be set by a memory fault) */
#if defined(TARGET_I386) && !defined(CONFIG_SOFTMMU)
                if (env->hflags & HF_SOFTMMU_MASK) {
                    env->hflags &= ~HF_SOFTMMU_MASK;
                    /* do not allow linking to another block */
                    T0 = 0;
                }
#endif
            }
        } else {
            env_to_regs();
        }
    } /* for(;;) */


#if defined(TARGET_I386)
#if defined(USE_CODE_COPY)
    if (env->native_fp_regs) {
        save_native_fp_state(env);
    }
#endif
    /* restore flags in standard format */
    env->eflags = env->eflags | cc_table[CC_OP].compute_all() | (DF & DF_MASK);

    /* restore global registers */
#ifdef reg_EAX
    EAX = saved_EAX;
#endif
#ifdef reg_ECX
    ECX = saved_ECX;
#endif
#ifdef reg_EDX
    EDX = saved_EDX;
#endif
#ifdef reg_EBX
    EBX = saved_EBX;
#endif
#ifdef reg_ESP
    ESP = saved_ESP;
#endif
#ifdef reg_EBP
    EBP = saved_EBP;
#endif
#ifdef reg_ESI
    ESI = saved_ESI;
#endif
#ifdef reg_EDI
    EDI = saved_EDI;
#endif
#elif defined(TARGET_ARM)
    env->cpsr = compute_cpsr();
#elif defined(TARGET_SPARC)
#elif defined(TARGET_PPC)
#else
#error unsupported target CPU
#endif
#ifdef __sparc__
    asm volatile ("mov %0, %%i7" : : "r" (saved_i7));
#endif
    T0 = saved_T0;
    T1 = saved_T1;
    T2 = saved_T2;
    env = saved_env;
    return ret;
}

/* must only be called from the generated code as an exception can be
   generated */
void tb_invalidate_page_range(target_ulong start, target_ulong end)
{
    /* XXX: cannot enable it yet because it yields to MMU exception
       where NIP != read address on PowerPC */
#if 0
    target_ulong phys_addr;
    phys_addr = get_phys_addr_code(env, start);
    tb_invalidate_phys_page_range(phys_addr, phys_addr + end - start, 0);
#endif
}

#if defined(TARGET_I386) && defined(CONFIG_USER_ONLY)

void cpu_x86_load_seg(CPUX86State *s, int seg_reg, int selector)
{
    CPUX86State *saved_env;

    saved_env = env;
    env = s;
    if (!(env->cr[0] & CR0_PE_MASK) || (env->eflags & VM_MASK)) {
        selector &= 0xffff;
        cpu_x86_load_seg_cache(env, seg_reg, selector, 
                               (selector << 4), 0xffff, 0);
    } else {
        load_seg(seg_reg, selector);
    }
    env = saved_env;
}

void cpu_x86_fsave(CPUX86State *s, uint8_t *ptr, int data32)
{
    CPUX86State *saved_env;

    saved_env = env;
    env = s;
    
    helper_fsave((target_ulong)ptr, data32);

    env = saved_env;
}

void cpu_x86_frstor(CPUX86State *s, uint8_t *ptr, int data32)
{
    CPUX86State *saved_env;

    saved_env = env;
    env = s;
    
    helper_frstor((target_ulong)ptr, data32);

    env = saved_env;
}

#endif /* TARGET_I386 */

#if !defined(CONFIG_SOFTMMU)

#if defined(TARGET_I386)

/* 'pc' is the host PC at which the exception was raised. 'address' is
   the effective address of the memory exception. 'is_write' is 1 if a
   write caused the exception and otherwise 0'. 'old_set' is the
   signal set which should be restored */
static inline int handle_cpu_signal(unsigned long pc, unsigned long address,
                                    int is_write, sigset_t *old_set, 
                                    void *puc)
{
    TranslationBlock *tb;
    int ret;

    if (cpu_single_env)
        env = cpu_single_env; /* XXX: find a correct solution for multithread */
#if defined(DEBUG_SIGNAL)
    qemu_printf("qemu: SIGSEGV pc=0x%08lx address=%08lx w=%d oldset=0x%08lx\n", 
                pc, address, is_write, *(unsigned long *)old_set);
#endif
    /* XXX: locking issue */
    if (is_write && page_unprotect(address, pc, puc)) {
        return 1;
    }

    /* see if it is an MMU fault */
    ret = cpu_x86_handle_mmu_fault(env, address, is_write, 
                                   ((env->hflags & HF_CPL_MASK) == 3), 0);
    if (ret < 0)
        return 0; /* not an MMU fault */
    if (ret == 0)
        return 1; /* the MMU fault was handled without causing real CPU fault */
    /* now we have a real cpu fault */
    tb = tb_find_pc(pc);
    if (tb) {
        /* the PC is inside the translated code. It means that we have
           a virtual CPU fault */
        cpu_restore_state(tb, env, pc, puc);
    }
    if (ret == 1) {
#if 0
        printf("PF exception: EIP=0x%08x CR2=0x%08x error=0x%x\n", 
               env->eip, env->cr[2], env->error_code);
#endif
        /* we restore the process signal mask as the sigreturn should
           do it (XXX: use sigsetjmp) */
        sigprocmask(SIG_SETMASK, old_set, NULL);
        raise_exception_err(EXCP0E_PAGE, env->error_code);
    } else {
        /* activate soft MMU for this block */
        env->hflags |= HF_SOFTMMU_MASK;
        cpu_resume_from_signal(env, puc);
    }
    /* never comes here */
    return 1;
}

#elif defined(TARGET_ARM)
static inline int handle_cpu_signal(unsigned long pc, unsigned long address,
                                    int is_write, sigset_t *old_set,
                                    void *puc)
{
    /* XXX: do more */
    return 0;
}
#elif defined(TARGET_SPARC)
static inline int handle_cpu_signal(unsigned long pc, unsigned long address,
                                    int is_write, sigset_t *old_set,
                                    void *puc)
{
    /* XXX: locking issue */
    if (is_write && page_unprotect(address, pc, puc)) {
        return 1;
    }
    return 0;
}
#elif defined (TARGET_PPC)
static inline int handle_cpu_signal(unsigned long pc, unsigned long address,
                                    int is_write, sigset_t *old_set,
                                    void *puc)
{
    TranslationBlock *tb;
    int ret;
    
#if 1
    if (cpu_single_env)
        env = cpu_single_env; /* XXX: find a correct solution for multithread */
#endif
#if defined(DEBUG_SIGNAL)
    printf("qemu: SIGSEGV pc=0x%08lx address=%08lx w=%d oldset=0x%08lx\n", 
           pc, address, is_write, *(unsigned long *)old_set);
#endif
    /* XXX: locking issue */
    if (is_write && page_unprotect(address, pc, puc)) {
        return 1;
    }

    /* see if it is an MMU fault */
    ret = cpu_ppc_handle_mmu_fault(env, address, is_write, msr_pr, 0);
    if (ret < 0)
        return 0; /* not an MMU fault */
    if (ret == 0)
        return 1; /* the MMU fault was handled without causing real CPU fault */

    /* now we have a real cpu fault */
    tb = tb_find_pc(pc);
    if (tb) {
        /* the PC is inside the translated code. It means that we have
           a virtual CPU fault */
        cpu_restore_state(tb, env, pc, puc);
    }
    if (ret == 1) {
#if 0
        printf("PF exception: NIP=0x%08x error=0x%x %p\n", 
               env->nip, env->error_code, tb);
#endif
    /* we restore the process signal mask as the sigreturn should
       do it (XXX: use sigsetjmp) */
        sigprocmask(SIG_SETMASK, old_set, NULL);
        do_raise_exception_err(env->exception_index, env->error_code);
    } else {
        /* activate soft MMU for this block */
        cpu_resume_from_signal(env, puc);
    }
    /* never comes here */
    return 1;
}
#else
#error unsupported target CPU
#endif

#if defined(__i386__)

#if defined(USE_CODE_COPY)
static void cpu_send_trap(unsigned long pc, int trap, 
                          struct ucontext *uc)
{
    TranslationBlock *tb;

    if (cpu_single_env)
        env = cpu_single_env; /* XXX: find a correct solution for multithread */
    /* now we have a real cpu fault */
    tb = tb_find_pc(pc);
    if (tb) {
        /* the PC is inside the translated code. It means that we have
           a virtual CPU fault */
        cpu_restore_state(tb, env, pc, uc);
    }
    sigprocmask(SIG_SETMASK, &uc->uc_sigmask, NULL);
    raise_exception_err(trap, env->error_code);
}
#endif

int cpu_signal_handler(int host_signum, struct siginfo *info, 
                       void *puc)
{
    struct ucontext *uc = puc;
    unsigned long pc;
    int trapno;

#ifndef REG_EIP
/* for glibc 2.1 */
#define REG_EIP    EIP
#define REG_ERR    ERR
#define REG_TRAPNO TRAPNO
#endif
    pc = uc->uc_mcontext.gregs[REG_EIP];
    trapno = uc->uc_mcontext.gregs[REG_TRAPNO];
#if defined(TARGET_I386) && defined(USE_CODE_COPY)
    if (trapno == 0x00 || trapno == 0x05) {
        /* send division by zero or bound exception */
        cpu_send_trap(pc, trapno, uc);
        return 1;
    } else
#endif
        return handle_cpu_signal(pc, (unsigned long)info->si_addr, 
                                 trapno == 0xe ? 
                                 (uc->uc_mcontext.gregs[REG_ERR] >> 1) & 1 : 0,
                                 &uc->uc_sigmask, puc);
}

#elif defined(__x86_64__)

int cpu_signal_handler(int host_signum, struct siginfo *info,
                       void *puc)
{
    struct ucontext *uc = puc;
    unsigned long pc;

    pc = uc->uc_mcontext.gregs[REG_RIP];
    return handle_cpu_signal(pc, (unsigned long)info->si_addr, 
                             uc->uc_mcontext.gregs[REG_TRAPNO] == 0xe ? 
                             (uc->uc_mcontext.gregs[REG_ERR] >> 1) & 1 : 0,
                             &uc->uc_sigmask, puc);
}

#elif defined(__powerpc__)

/***********************************************************************
 * signal context platform-specific definitions
 * From Wine
 */
#ifdef linux
/* All Registers access - only for local access */
# define REG_sig(reg_name, context)		((context)->uc_mcontext.regs->reg_name)
/* Gpr Registers access  */
# define GPR_sig(reg_num, context)		REG_sig(gpr[reg_num], context)
# define IAR_sig(context)			REG_sig(nip, context)	/* Program counter */
# define MSR_sig(context)			REG_sig(msr, context)   /* Machine State Register (Supervisor) */
# define CTR_sig(context)			REG_sig(ctr, context)   /* Count register */
# define XER_sig(context)			REG_sig(xer, context) /* User's integer exception register */
# define LR_sig(context)			REG_sig(link, context) /* Link register */
# define CR_sig(context)			REG_sig(ccr, context) /* Condition register */
/* Float Registers access  */
# define FLOAT_sig(reg_num, context)		(((double*)((char*)((context)->uc_mcontext.regs+48*4)))[reg_num])
# define FPSCR_sig(context)			(*(int*)((char*)((context)->uc_mcontext.regs+(48+32*2)*4)))
/* Exception Registers access */
# define DAR_sig(context)			REG_sig(dar, context)
# define DSISR_sig(context)			REG_sig(dsisr, context)
# define TRAP_sig(context)			REG_sig(trap, context)
#endif /* linux */

#ifdef __APPLE__
# include <sys/ucontext.h>
typedef struct ucontext SIGCONTEXT;
/* All Registers access - only for local access */
# define REG_sig(reg_name, context)		((context)->uc_mcontext->ss.reg_name)
# define FLOATREG_sig(reg_name, context)	((context)->uc_mcontext->fs.reg_name)
# define EXCEPREG_sig(reg_name, context)	((context)->uc_mcontext->es.reg_name)
# define VECREG_sig(reg_name, context)		((context)->uc_mcontext->vs.reg_name)
/* Gpr Registers access */
# define GPR_sig(reg_num, context)		REG_sig(r##reg_num, context)
# define IAR_sig(context)			REG_sig(srr0, context)	/* Program counter */
# define MSR_sig(context)			REG_sig(srr1, context)  /* Machine State Register (Supervisor) */
# define CTR_sig(context)			REG_sig(ctr, context)
# define XER_sig(context)			REG_sig(xer, context) /* Link register */
# define LR_sig(context)			REG_sig(lr, context)  /* User's integer exception register */
# define CR_sig(context)			REG_sig(cr, context)  /* Condition register */
/* Float Registers access */
# define FLOAT_sig(reg_num, context)		FLOATREG_sig(fpregs[reg_num], context)
# define FPSCR_sig(context)			((double)FLOATREG_sig(fpscr, context))
/* Exception Registers access */
# define DAR_sig(context)			EXCEPREG_sig(dar, context)     /* Fault registers for coredump */
# define DSISR_sig(context)			EXCEPREG_sig(dsisr, context)
# define TRAP_sig(context)			EXCEPREG_sig(exception, context) /* number of powerpc exception taken */
#endif /* __APPLE__ */

int cpu_signal_handler(int host_signum, struct siginfo *info, 
                       void *puc)
{
    struct ucontext *uc = puc;
    unsigned long pc;
    int is_write;

    pc = IAR_sig(uc);
    is_write = 0;
#if 0
    /* ppc 4xx case */
    if (DSISR_sig(uc) & 0x00800000)
        is_write = 1;
#else
    if (TRAP_sig(uc) != 0x400 && (DSISR_sig(uc) & 0x02000000))
        is_write = 1;
#endif
    return handle_cpu_signal(pc, (unsigned long)info->si_addr, 
                             is_write, &uc->uc_sigmask, puc);
}

#elif defined(__alpha__)

int cpu_signal_handler(int host_signum, struct siginfo *info, 
                           void *puc)
{
    struct ucontext *uc = puc;
    uint32_t *pc = uc->uc_mcontext.sc_pc;
    uint32_t insn = *pc;
    int is_write = 0;

    /* XXX: need kernel patch to get write flag faster */
    switch (insn >> 26) {
    case 0x0d: // stw
    case 0x0e: // stb
    case 0x0f: // stq_u
    case 0x24: // stf
    case 0x25: // stg
    case 0x26: // sts
    case 0x27: // stt
    case 0x2c: // stl
    case 0x2d: // stq
    case 0x2e: // stl_c
    case 0x2f: // stq_c
	is_write = 1;
    }

    return handle_cpu_signal(pc, (unsigned long)info->si_addr, 
                             is_write, &uc->uc_sigmask, puc);
}
#elif defined(__sparc__)

int cpu_signal_handler(int host_signum, struct siginfo *info, 
                       void *puc)
{
    uint32_t *regs = (uint32_t *)(info + 1);
    void *sigmask = (regs + 20);
    unsigned long pc;
    int is_write;
    uint32_t insn;
    
    /* XXX: is there a standard glibc define ? */
    pc = regs[1];
    /* XXX: need kernel patch to get write flag faster */
    is_write = 0;
    insn = *(uint32_t *)pc;
    if ((insn >> 30) == 3) {
      switch((insn >> 19) & 0x3f) {
      case 0x05: // stb
      case 0x06: // sth
      case 0x04: // st
      case 0x07: // std
      case 0x24: // stf
      case 0x27: // stdf
      case 0x25: // stfsr
	is_write = 1;
	break;
      }
    }
    return handle_cpu_signal(pc, (unsigned long)info->si_addr, 
                             is_write, sigmask, NULL);
}

#elif defined(__arm__)

int cpu_signal_handler(int host_signum, struct siginfo *info, 
                       void *puc)
{
    struct ucontext *uc = puc;
    unsigned long pc;
    int is_write;
    
    pc = uc->uc_mcontext.gregs[R15];
    /* XXX: compute is_write */
    is_write = 0;
    return handle_cpu_signal(pc, (unsigned long)info->si_addr, 
                             is_write,
                             &uc->uc_sigmask);
}

#elif defined(__mc68000)

int cpu_signal_handler(int host_signum, struct siginfo *info, 
                       void *puc)
{
    struct ucontext *uc = puc;
    unsigned long pc;
    int is_write;
    
    pc = uc->uc_mcontext.gregs[16];
    /* XXX: compute is_write */
    is_write = 0;
    return handle_cpu_signal(pc, (unsigned long)info->si_addr, 
                             is_write,
                             &uc->uc_sigmask, puc);
}

#else

#error host CPU specific signal handler needed

#endif

#endif /* !defined(CONFIG_SOFTMMU) */