2 * i386 emulator main execution loop
4 * Copyright (c) 2003 Fabrice Bellard
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 #include "exec-i386.h"
24 //#define DEBUG_SIGNAL
26 /* main execution loop */
30 spinlock_t global_cpu_lock
= SPIN_LOCK_UNLOCKED
;
34 spin_lock(&global_cpu_lock
);
39 spin_unlock(&global_cpu_lock
);
42 /* exception support */
43 /* NOTE: not static to force relocation generation by GCC */
44 void raise_exception_err(int exception_index
, int error_code
)
46 /* NOTE: the register at this point must be saved by hand because
47 longjmp restore them */
49 /* We have to stay in the same register window as our caller,
52 __asm__
__volatile__("restore\n\t"
56 env
->regs
[R_EAX
] = EAX
;
59 env
->regs
[R_ECX
] = ECX
;
62 env
->regs
[R_EDX
] = EDX
;
65 env
->regs
[R_EBX
] = EBX
;
68 env
->regs
[R_ESP
] = ESP
;
71 env
->regs
[R_EBP
] = EBP
;
74 env
->regs
[R_ESI
] = ESI
;
77 env
->regs
[R_EDI
] = EDI
;
79 env
->exception_index
= exception_index
;
80 env
->error_code
= error_code
;
81 longjmp(env
->jmp_env
, 1);
84 /* short cut if error_code is 0 or not present */
85 void raise_exception(int exception_index
)
87 raise_exception_err(exception_index
, 0);
90 int cpu_x86_exec(CPUX86State
*env1
)
92 int saved_T0
, saved_T1
, saved_A0
;
93 CPUX86State
*saved_env
;
118 int code_gen_size
, ret
, code_size
;
119 void (*gen_func
)(void);
120 TranslationBlock
*tb
, **ptb
;
121 uint8_t *tc_ptr
, *cs_base
, *pc
;
124 /* first we save global registers */
132 EAX
= env
->regs
[R_EAX
];
136 ECX
= env
->regs
[R_ECX
];
140 EDX
= env
->regs
[R_EDX
];
144 EBX
= env
->regs
[R_EBX
];
148 ESP
= env
->regs
[R_ESP
];
152 EBP
= env
->regs
[R_EBP
];
156 ESI
= env
->regs
[R_ESI
];
160 EDI
= env
->regs
[R_EDI
];
163 /* put eflags in CPU temporary format */
164 CC_SRC
= env
->eflags
& (CC_O
| CC_S
| CC_Z
| CC_A
| CC_P
| CC_C
);
165 DF
= 1 - (2 * ((env
->eflags
>> 10) & 1));
166 CC_OP
= CC_OP_EFLAGS
;
167 env
->eflags
&= ~(DF_MASK
| CC_O
| CC_S
| CC_Z
| CC_A
| CC_P
| CC_C
);
168 env
->interrupt_request
= 0;
170 /* prepare setjmp context for exception handling */
171 if (setjmp(env
->jmp_env
) == 0) {
172 T0
= 0; /* force lookup of first TB */
174 if (env
->interrupt_request
) {
175 raise_exception(EXCP_INTERRUPT
);
179 /* XXX: save all volatile state in cpu state */
180 /* restore flags in standard format */
181 env
->regs
[R_EAX
] = EAX
;
182 env
->regs
[R_EBX
] = EBX
;
183 env
->regs
[R_ECX
] = ECX
;
184 env
->regs
[R_EDX
] = EDX
;
185 env
->regs
[R_ESI
] = ESI
;
186 env
->regs
[R_EDI
] = EDI
;
187 env
->regs
[R_EBP
] = EBP
;
188 env
->regs
[R_ESP
] = ESP
;
189 env
->eflags
= env
->eflags
| cc_table
[CC_OP
].compute_all() | (DF
& DF_MASK
);
190 cpu_x86_dump_state(env
, logfile
, 0);
191 env
->eflags
&= ~(DF_MASK
| CC_O
| CC_S
| CC_Z
| CC_A
| CC_P
| CC_C
);
194 /* we compute the CPU state. We assume it will not
195 change during the whole generated block. */
196 flags
= env
->seg_cache
[R_CS
].seg_32bit
<< GEN_FLAG_CODE32_SHIFT
;
197 flags
|= env
->seg_cache
[R_SS
].seg_32bit
<< GEN_FLAG_SS32_SHIFT
;
198 flags
|= (((unsigned long)env
->seg_cache
[R_DS
].base
|
199 (unsigned long)env
->seg_cache
[R_ES
].base
|
200 (unsigned long)env
->seg_cache
[R_SS
].base
) != 0) <<
201 GEN_FLAG_ADDSEG_SHIFT
;
202 if (!(env
->eflags
& VM_MASK
)) {
203 flags
|= (env
->segs
[R_CS
] & 3) << GEN_FLAG_CPL_SHIFT
;
205 /* NOTE: a dummy CPL is kept */
206 flags
|= (1 << GEN_FLAG_VM_SHIFT
);
207 flags
|= (3 << GEN_FLAG_CPL_SHIFT
);
209 flags
|= (env
->eflags
& (IOPL_MASK
| TF_MASK
));
210 cs_base
= env
->seg_cache
[R_CS
].base
;
211 pc
= cs_base
+ env
->eip
;
212 tb
= tb_find(&ptb
, (unsigned long)pc
, (unsigned long)cs_base
,
216 /* if no translated code available, then translate it now */
217 tb
= tb_alloc((unsigned long)pc
);
219 /* flush must be done */
221 /* cannot fail at this point */
222 tb
= tb_alloc((unsigned long)pc
);
223 /* don't forget to invalidate previous TB info */
224 ptb
= &tb_hash
[tb_hash_func((unsigned long)pc
)];
227 tc_ptr
= code_gen_ptr
;
229 ret
= cpu_x86_gen_code(code_gen_ptr
, CODE_GEN_MAX_SIZE
,
230 &code_gen_size
, pc
, cs_base
, flags
,
232 /* if invalid instruction, signal it */
234 /* NOTE: the tb is allocated but not linked, so we
236 spin_unlock(&tb_lock
);
237 raise_exception(EXCP06_ILLOP
);
240 tb
->size
= code_size
;
241 tb
->cs_base
= (unsigned long)cs_base
;
243 tb
->hash_next
= NULL
;
245 code_gen_ptr
= (void *)(((unsigned long)code_gen_ptr
+ code_gen_size
+ CODE_GEN_ALIGN
- 1) & ~(CODE_GEN_ALIGN
- 1));
246 spin_unlock(&tb_lock
);
250 fprintf(logfile
, "Trace 0x%08lx [0x%08lx] %s\n",
251 (long)tb
->tc_ptr
, (long)tb
->pc
,
252 lookup_symbol((void *)tb
->pc
));
255 /* see if we can patch the calling TB */
256 if (T0
!= 0 && !(env
->eflags
& TF_MASK
)) {
258 tb_add_jump((TranslationBlock
*)(T0
& ~3), T0
& 3, tb
);
259 spin_unlock(&tb_lock
);
264 /* execute the generated code */
265 gen_func
= (void *)tc_ptr
;
267 __asm__
__volatile__("call %0\n\t"
271 : "i0", "i1", "i2", "i3", "i4", "i5");
277 ret
= env
->exception_index
;
279 /* restore flags in standard format */
280 env
->eflags
= env
->eflags
| cc_table
[CC_OP
].compute_all() | (DF
& DF_MASK
);
282 /* restore global registers */
314 void cpu_x86_interrupt(CPUX86State
*s
)
316 s
->interrupt_request
= 1;
320 void cpu_x86_load_seg(CPUX86State
*s
, int seg_reg
, int selector
)
322 CPUX86State
*saved_env
;
326 load_seg(seg_reg
, selector
);
340 #include <sys/ucontext.h>
342 /* 'pc' is the host PC at which the exception was raised. 'address' is
343 the effective address of the memory exception. 'is_write' is 1 if a
344 write caused the exception and otherwise 0'. 'old_set' is the
345 signal set which should be restored */
346 static inline int handle_cpu_signal(unsigned long pc
, unsigned long address
,
347 int is_write
, sigset_t
*old_set
)
349 #if defined(DEBUG_SIGNAL)
350 printf("qemu: SIGSEGV pc=0x%08lx address=%08lx wr=%d oldset=0x%08lx\n",
351 pc
, address
, is_write
, *(unsigned long *)old_set
);
353 /* XXX: locking issue */
354 if (is_write
&& page_unprotect(address
)) {
357 if (pc
>= (unsigned long)code_gen_buffer
&&
358 pc
< (unsigned long)code_gen_buffer
+ CODE_GEN_BUFFER_SIZE
) {
359 /* the PC is inside the translated code. It means that we have
360 a virtual CPU fault */
361 /* we restore the process signal mask as the sigreturn should
363 sigprocmask(SIG_SETMASK
, old_set
, NULL
);
364 /* XXX: need to compute virtual pc position by retranslating
365 code. The rest of the CPU state should be correct. */
367 raise_exception_err(EXCP0E_PAGE
, 4 | (is_write
<< 1));
368 /* never comes here */
375 #if defined(__i386__)
377 int cpu_x86_signal_handler(int host_signum
, struct siginfo
*info
,
380 struct ucontext
*uc
= puc
;
387 #define REG_TRAPNO TRAPNO
389 pc
= uc
->uc_mcontext
.gregs
[REG_EIP
];
390 return handle_cpu_signal(pc
, (unsigned long)info
->si_addr
,
391 uc
->uc_mcontext
.gregs
[REG_TRAPNO
] == 0xe ?
392 (uc
->uc_mcontext
.gregs
[REG_ERR
] >> 1) & 1 : 0,
396 #elif defined(__powerpc)
398 int cpu_x86_signal_handler(int host_signum
, struct siginfo
*info
,
401 struct ucontext
*uc
= puc
;
402 struct pt_regs
*regs
= uc
->uc_mcontext
.regs
;
410 if (regs
->dsisr
& 0x00800000)
413 if (regs
->trap
!= 0x400 && (regs
->dsisr
& 0x02000000))
416 return handle_cpu_signal(pc
, (unsigned long)info
->si_addr
,
417 is_write
, &uc
->uc_sigmask
);
422 #error CPU specific signal handler needed