2 * This software is part of the SBCL system. See the README file for
5 * This software is derived from the CMU CL system, which was
6 * written at Carnegie Mellon University and released into the
7 * public domain. The software is in the public domain and is
8 * provided with absolutely no warranty. See the COPYING and CREDITS
9 * files for more information.
24 #include "interrupt.h"
26 #include "breakpoint.h"
29 #include "genesis/static-symbols.h"
30 #include "genesis/symbol.h"
32 #define BREAKPOINT_INST 0xcc /* INT3 */
34 unsigned long fast_random_state
= 1;
40 arch_get_bad_addr(int sig
, siginfo_t
*code
, os_context_t
*context
)
42 return (os_vm_address_t
)code
->si_addr
;
47 * hacking signal contexts
49 * (This depends both on architecture, which determines what we might
50 * want to get to, and on OS, which determines how we get to it.)
53 os_context_register_t
*
54 context_eflags_addr(os_context_t
*context
)
57 /* KLUDGE: As of kernel 2.2.14 on Red Hat 6.2, there's code in the
58 * <sys/ucontext.h> file to define symbolic names for offsets into
59 * gregs[], but it's conditional on __USE_GNU and not defined, so
60 * we need to do this nasty absolute index magic number thing
62 return &context
->uc_mcontext
.gregs
[17];
63 #elif defined __FreeBSD__
64 return &context
->uc_mcontext
.mc_rflags
;
65 #elif defined LISP_FEATURE_DARWIN
66 return &context
->uc_mcontext
->ss
.rflags
;
67 #elif defined __OpenBSD__
68 return &context
->sc_eflags
;
74 void arch_skip_instruction(os_context_t
*context
)
76 /* Assuming we get here via an INT3 xxx instruction, the PC now
77 * points to the interrupt code (a Lisp value) so we just move
78 * past it. Skip the code; after that, if the code is an
79 * error-trap or cerror-trap then skip the data bytes that follow. */
85 /* Get and skip the Lisp interrupt code. */
86 code
= *(char*)(*os_context_pc_addr(context
))++;
91 /* Lisp error arg vector length */
92 vlen
= *(char*)(*os_context_pc_addr(context
))++;
93 /* Skip Lisp error arg data bytes. */
95 ++*os_context_pc_addr(context
);
99 case trap_Breakpoint
: /* not tested */
100 case trap_FunEndBreakpoint
: /* not tested */
103 case trap_PendingInterrupt
:
105 case trap_SingleStepAround
:
106 case trap_SingleStepBefore
:
107 /* only needed to skip the Code */
111 fprintf(stderr
,"[arch_skip_inst invalid code %ld\n]\n",code
);
116 "/[arch_skip_inst resuming at %x]\n",
117 *os_context_pc_addr(context
)));
121 arch_internal_error_arguments(os_context_t
*context
)
123 return 1 + (unsigned char *)(*os_context_pc_addr(context
));
127 arch_pseudo_atomic_atomic(os_context_t
*context
)
129 return get_pseudo_atomic_atomic(arch_os_get_current_thread());
133 arch_set_pseudo_atomic_interrupted(os_context_t
*context
)
135 struct thread
*thread
= arch_os_get_current_thread();
136 set_pseudo_atomic_interrupted(thread
);
140 arch_clear_pseudo_atomic_interrupted(os_context_t
*context
)
142 struct thread
*thread
= arch_os_get_current_thread();
143 clear_pseudo_atomic_interrupted(thread
);
147 * This stuff seems to get called for TRACE and debug activity.
151 arch_install_breakpoint(void *pc
)
153 unsigned int result
= *(unsigned int*)pc
;
155 *(char*)pc
= BREAKPOINT_INST
; /* x86 INT3 */
156 *((char*)pc
+1) = trap_Breakpoint
; /* Lisp trap code */
162 arch_remove_breakpoint(void *pc
, unsigned int orig_inst
)
164 *((char *)pc
) = orig_inst
& 0xff;
165 *((char *)pc
+ 1) = (orig_inst
& 0xff00) >> 8;
168 /* When single stepping, single_stepping holds the original instruction
170 unsigned int *single_stepping
= NULL
;
171 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
172 unsigned int single_step_save1
;
173 unsigned int single_step_save2
;
174 unsigned int single_step_save3
;
178 arch_do_displaced_inst(os_context_t
*context
, unsigned int orig_inst
)
180 unsigned int *pc
= (unsigned int*)(*os_context_pc_addr(context
));
182 /* Put the original instruction back. */
183 *((char *)pc
) = orig_inst
& 0xff;
184 *((char *)pc
+ 1) = (orig_inst
& 0xff00) >> 8;
186 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
187 /* Install helper instructions for the single step:
188 * pushf; or [esp],0x100; popf. */
189 single_step_save1
= *(pc
-3);
190 single_step_save2
= *(pc
-2);
191 single_step_save3
= *(pc
-1);
192 *(pc
-3) = 0x9c909090;
193 *(pc
-2) = 0x00240c81;
194 *(pc
-1) = 0x9d000001;
196 *context_eflags_addr(context
) |= 0x100;
199 single_stepping
= pc
;
201 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
202 *os_context_pc_addr(context
) = (os_context_register_t
)((char *)pc
- 9);
207 arch_handle_breakpoint(os_context_t
*context
)
209 --*os_context_pc_addr(context
);
210 handle_breakpoint(context
);
214 arch_handle_fun_end_breakpoint(os_context_t
*context
)
216 --*os_context_pc_addr(context
);
217 *os_context_pc_addr(context
) =
218 (unsigned long)handle_fun_end_breakpoint(context
);
222 arch_handle_single_step_trap(os_context_t
*context
, int trap
)
224 arch_skip_instruction(context
);
225 /* On x86-64 the fdefn / function is always in RAX, so we pass
226 * 0 as the register_offset. */
227 handle_single_step_trap(context
, trap
, 0);
232 sigtrap_handler(int signal
, siginfo_t
*info
, void *void_context
)
234 os_context_t
*context
= (os_context_t
*)void_context
;
237 if (single_stepping
&& (signal
==SIGTRAP
))
239 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
240 /* Un-install single step helper instructions. */
241 *(single_stepping
-3) = single_step_save1
;
242 *(single_stepping
-2) = single_step_save2
;
243 *(single_stepping
-1) = single_step_save3
;
245 *context_eflags_addr(context
) ^= 0x100;
247 /* Re-install the breakpoint if possible. */
248 if ((char *)*os_context_pc_addr(context
) ==
249 (char *)single_stepping
+ 1) {
250 fprintf(stderr
, "warning: couldn't reinstall breakpoint\n");
252 *((char *)single_stepping
) = BREAKPOINT_INST
; /* x86 INT3 */
253 *((char *)single_stepping
+1) = trap_Breakpoint
;
256 single_stepping
= NULL
;
260 /* This is just for info in case the monitor wants to print an
262 current_control_stack_pointer
=
263 (lispobj
*)*os_context_sp_addr(context
);
265 /* FIXME: CMUCL puts the float control restoration code here.
266 Thus, it seems to me that single-stepping won't restore the
267 float control. Since SBCL currently doesn't support
268 single-stepping (as far as I can tell) this is somewhat moot,
269 but it might be worth either moving this code up or deleting
270 the single-stepping code entirely. -- CSR, 2002-07-15 */
271 #if defined(LISP_FEATURE_LINUX) || defined(RESTORE_FP_CONTROL_FROM_CONTEXT)
272 os_restore_fp_control(context
);
275 /* On entry %eip points just after the INT3 byte and aims at the
276 * 'kind' value (eg trap_Cerror). For error-trap and Cerror-trap a
277 * number of bytes will follow, the first is the length of the byte
278 * arguments to follow. */
279 trap
= *(unsigned char *)(*os_context_pc_addr(context
));
281 handle_trap(context
, trap
);
285 sigill_handler(int signal
, siginfo_t
*siginfo
, void *void_context
) {
286 os_context_t
*context
= (os_context_t
*)void_context
;
288 /* Triggering SIGTRAP using int3 is unreliable on OS X/x86, so
289 * we need to use illegal instructions for traps.
291 #if defined(LISP_FEATURE_DARWIN) && !defined(LISP_FEATURE_MACH_EXCEPTION_HANDLER)
292 if (*((unsigned short *)*os_context_pc_addr(context
)) == 0x0b0f) {
293 *os_context_pc_addr(context
) += 2;
294 return sigtrap_handler(signal
, siginfo
, void_context
);
298 fake_foreign_function_call(context
);
299 lose("Unhandled SIGILL.");
302 #ifdef X86_64_SIGFPE_FIXUP
303 #define MXCSR_IE (0x01) /* Invalid Operation */
304 #define MXCSR_DE (0x02) /* Denormal */
305 #define MXCSR_ZE (0x04) /* Devide-by-Zero */
306 #define MXCSR_OE (0x08) /* Overflow */
307 #define MXCSR_UE (0x10) /* Underflow */
308 #define MXCSR_PE (0x20) /* Precision */
311 mxcsr_to_code(unsigned int mxcsr
)
313 /* Extract unmasked exception bits. */
314 mxcsr
&= ~(mxcsr
>> 7) & 0x3F;
316 /* This order is defined at "Intel 64 and IA-32 Architectures
317 * Software Developerfs Manual" Volume 1: "Basic Architecture",
318 * 4.9.2 "Floating-Point Exception Priority". */
319 if (mxcsr
& MXCSR_IE
)
321 else if (mxcsr
& MXCSR_ZE
)
323 else if (mxcsr
& MXCSR_DE
)
325 else if (mxcsr
& MXCSR_OE
)
327 else if (mxcsr
& MXCSR_UE
)
329 else if (mxcsr
& MXCSR_PE
)
336 sigfpe_handler(int signal
, siginfo_t
*siginfo
, void *void_context
)
338 os_context_t
*context
= arch_os_get_context(&void_context
);
339 unsigned int *mxcsr
= arch_os_context_mxcsr_addr(context
);
341 if (siginfo
->si_code
== 0) { /* XMM exception */
342 siginfo
->si_code
= mxcsr_to_code(*mxcsr
);
344 /* Clear sticky exception flag. */
348 interrupt_handle_now(signal
, siginfo
, context
);
353 arch_install_interrupt_handlers()
355 SHOW("entering arch_install_interrupt_handlers()");
357 /* Note: The old CMU CL code here used sigtrap_handler() to handle
358 * SIGILL as well as SIGTRAP. I couldn't see any reason to do
359 * things that way. So, I changed to separate handlers when
360 * debugging a problem on OpenBSD, where SBCL wasn't catching
361 * SIGILL properly, but was instead letting the process be
362 * terminated with an "Illegal instruction" output. If this change
363 * turns out to break something (maybe breakpoint handling on some
364 * OS I haven't tested on?) and we have to go back to the old CMU
365 * CL way, I hope there will at least be a comment to explain
366 * why.. -- WHN 2001-06-07 */
367 #if !defined(LISP_FEATURE_MACH_EXCEPTION_HANDLER)
368 undoably_install_low_level_interrupt_handler(SIGILL
, sigill_handler
);
369 undoably_install_low_level_interrupt_handler(SIGTRAP
, sigtrap_handler
);
372 #ifdef X86_64_SIGFPE_FIXUP
373 undoably_install_low_level_interrupt_handler(SIGFPE
, sigfpe_handler
);
376 SHOW("returning from arch_install_interrupt_handlers()");
379 #ifdef LISP_FEATURE_LINKAGE_TABLE
380 /* FIXME: It might be cleaner to generate these from the lisp side of
385 arch_write_linkage_table_jmp(char * reloc
, void * fun
)
387 unsigned long addr
= (unsigned long) fun
;
390 *reloc
++ = 0xFF; /* Opcode for near jump to absolute reg/mem64. */
391 *reloc
++ = 0x25; /* ModRM #b00 100 101, i.e. RIP-relative. */
392 *reloc
++ = 0x00; /* 32-bit displacement field = 0 */
393 *reloc
++ = 0x00; /* ... */
394 *reloc
++ = 0x00; /* ... */
395 *reloc
++ = 0x00; /* ... */
397 for (i
= 0; i
< 8; i
++) {
398 *reloc
++ = addr
& 0xff;
402 /* write a nop for good measure. */
407 arch_write_linkage_table_ref(void * reloc
, void * data
)
409 *(unsigned long *)reloc
= (unsigned long)data
;
414 /* These setup and check *both* the sse2 and x87 FPUs. While lisp code
415 only uses the sse2 FPU, other code (such as libc) may use the x87 FPU.
423 /* return the x87 exception flags ored in with the sse2
424 * control+status flags */
425 asm ("fnstsw %0" : "=m" (temp
));
428 asm ("stmxcsr %0" : "=m" (temp
));
430 /* flip exception mask bits */
431 return result
^ (0x3F << 7);
437 unsigned short unused1
;
439 unsigned short unused2
;
440 unsigned int other_regs
[5];
444 arch_set_fp_modes(unsigned int mxcsr
)
449 /* turn trap enable bits into exception mask */
453 asm ("fnstenv %0" : "=m" (f_env
));
454 /* set control word: always long double precision
455 * get traps and rounding from mxcsr word */
456 f_env
.cw
= 0x300 | ((mxcsr
>> 7) & 0x3F) | (((mxcsr
>> 13) & 0x3) << 10);
457 /* set status word: only override exception flags, from mxcsr */
459 f_env
.sw
|= (mxcsr
& 0x3F);
461 asm ("fldenv %0" : : "m" (f_env
));
463 /* now, simply, load up the mxcsr register */
465 asm ("ldmxcsr %0" : : "m" (temp
));