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);
208 sigtrap_handler(int signal, siginfo_t *info, void *void_context)
210 int code = info->si_code;
211 os_context_t *context = (os_context_t*)void_context;
214 if (single_stepping && (signal==SIGTRAP))
216 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
217 /* Un-install single step helper instructions. */
218 *(single_stepping-3) = single_step_save1;
219 *(single_stepping-2) = single_step_save2;
220 *(single_stepping-1) = single_step_save3;
222 *context_eflags_addr(context) ^= 0x100;
224 /* Re-install the breakpoint if possible. */
225 if ((char *)*os_context_pc_addr(context) ==
226 (char *)single_stepping + 1) {
227 fprintf(stderr, "warning: couldn't reinstall breakpoint\n");
229 *((char *)single_stepping) = BREAKPOINT_INST; /* x86 INT3 */
230 *((char *)single_stepping+1) = trap_Breakpoint;
233 single_stepping = NULL;
237 /* This is just for info in case the monitor wants to print an
239 current_control_stack_pointer =
240 (lispobj *)*os_context_sp_addr(context);
242 /* FIXME: CMUCL puts the float control restoration code here.
243 Thus, it seems to me that single-stepping won't restore the
244 float control. Since SBCL currently doesn't support
245 single-stepping (as far as I can tell) this is somewhat moot,
246 but it might be worth either moving this code up or deleting
247 the single-stepping code entirely. -- CSR, 2002-07-15 */
248 #if defined(LISP_FEATURE_LINUX) || defined(RESTORE_FP_CONTROL_FROM_CONTEXT)
249 os_restore_fp_control(context);
252 /* On entry %eip points just after the INT3 byte and aims at the
253 * 'kind' value (eg trap_Cerror). For error-trap and Cerror-trap a
254 * number of bytes will follow, the first is the length of the byte
255 * arguments to follow. */
256 trap = *(unsigned char *)(*os_context_pc_addr(context));
259 case trap_PendingInterrupt:
260 FSHOW((stderr, "/<trap pending interrupt>\n"));
261 arch_skip_instruction(context);
262 interrupt_handle_pending(context);
266 /* Note: the old CMU CL code tried to save FPU state
267 * here, and restore it after we do our thing, but there
268 * seems to be no point in doing that, since we're just
269 * going to lose(..) anyway. */
270 fake_foreign_function_call(context);
271 lose("%%PRIMITIVE HALT called; the party is over.\n");
275 FSHOW((stderr, "<trap error/cerror %d>\n", trap));
276 interrupt_internal_error(signal, info, context, trap==trap_Cerror);
279 case trap_Breakpoint:
280 --*os_context_pc_addr(context);
281 handle_breakpoint(signal, info, context);
284 case trap_FunEndBreakpoint:
285 --*os_context_pc_addr(context);
286 *os_context_pc_addr(context) =
287 (unsigned long)handle_fun_end_breakpoint(signal, info, context);
290 case trap_SingleStepAround:
291 case trap_SingleStepBefore:
292 arch_skip_instruction(context);
293 /* On x86-64 the fdefn / function is always in RAX, so we pass
294 * 0 as the register_offset. */
295 handle_single_step_trap(context, trap, 0);
299 FSHOW((stderr,"/[C--trap default %d %d %x]\n",
300 signal, code, context));
301 interrupt_handle_now(signal, info, context);
307 sigill_handler(int signal, siginfo_t *siginfo, void *void_context) {
308 os_context_t *context = (os_context_t*)void_context;
310 /* Triggering SIGTRAP using int3 is unreliable on OS X/x86, so
311 * we need to use illegal instructions for traps.
313 #if defined(LISP_FEATURE_DARWIN) && !defined(LISP_FEATURE_MACH_EXCEPTION_HANDLER)
314 if (*((unsigned short *)*os_context_pc_addr(context)) == 0x0b0f) {
315 *os_context_pc_addr(context) += 2;
316 return sigtrap_handler(signal, siginfo, void_context);
320 fake_foreign_function_call(context);
321 lose("fake_foreign_function_call fell through");
324 #ifdef X86_64_SIGFPE_FIXUP
325 #define MXCSR_IE (0x01) /* Invalid Operation */
326 #define MXCSR_DE (0x02) /* Denormal */
327 #define MXCSR_ZE (0x04) /* Devide-by-Zero */
328 #define MXCSR_OE (0x08) /* Overflow */
329 #define MXCSR_UE (0x10) /* Underflow */
330 #define MXCSR_PE (0x20) /* Precision */
333 mxcsr_to_code(unsigned int mxcsr)
335 /* Extract unmasked exception bits. */
336 mxcsr &= ~(mxcsr >> 7) & 0x3F;
338 /* This order is defined at "Intel 64 and IA-32 Architectures
339 * Software Developerfs Manual" Volume 1: "Basic Architecture",
340 * 4.9.2 "Floating-Point Exception Priority". */
341 if (mxcsr & MXCSR_IE)
343 else if (mxcsr & MXCSR_ZE)
345 else if (mxcsr & MXCSR_DE)
347 else if (mxcsr & MXCSR_OE)
349 else if (mxcsr & MXCSR_UE)
351 else if (mxcsr & MXCSR_PE)
358 sigfpe_handler(int signal, siginfo_t *siginfo, void *void_context)
360 os_context_t *context = arch_os_get_context(&void_context);
361 unsigned int *mxcsr = arch_os_context_mxcsr_addr(context);
363 if (siginfo->si_code == 0) { /* XMM exception */
364 siginfo->si_code = mxcsr_to_code(*mxcsr);
366 /* Clear sticky exception flag. */
370 interrupt_handle_now(signal, siginfo, context);
375 arch_install_interrupt_handlers()
377 SHOW("entering arch_install_interrupt_handlers()");
379 /* Note: The old CMU CL code here used sigtrap_handler() to handle
380 * SIGILL as well as SIGTRAP. I couldn't see any reason to do
381 * things that way. So, I changed to separate handlers when
382 * debugging a problem on OpenBSD, where SBCL wasn't catching
383 * SIGILL properly, but was instead letting the process be
384 * terminated with an "Illegal instruction" output. If this change
385 * turns out to break something (maybe breakpoint handling on some
386 * OS I haven't tested on?) and we have to go back to the old CMU
387 * CL way, I hope there will at least be a comment to explain
388 * why.. -- WHN 2001-06-07 */
389 #if !defined(LISP_FEATURE_MACH_EXCEPTION_HANDLER)
390 undoably_install_low_level_interrupt_handler(SIGILL , sigill_handler);
391 undoably_install_low_level_interrupt_handler(SIGTRAP, sigtrap_handler);
394 #ifdef X86_64_SIGFPE_FIXUP
395 undoably_install_low_level_interrupt_handler(SIGFPE, sigfpe_handler);
398 SHOW("returning from arch_install_interrupt_handlers()");
401 /* This is implemented in assembly language and called from C: */
403 call_into_lisp(lispobj fun, lispobj *args, int nargs);
405 /* These functions are an interface to the Lisp call-in facility.
406 * Since this is C we can know nothing about the calling environment.
407 * The control stack might be the C stack if called from the monitor
408 * or the Lisp stack if called as a result of an interrupt or maybe
409 * even a separate stack. The args are most likely on that stack but
410 * could be in registers depending on what the compiler likes. So we
411 * copy the args into a portable vector and let the assembly language
412 * call-in function figure it out. */
415 funcall0(lispobj function)
417 lispobj *args = NULL;
419 FSHOW((stderr, "/entering funcall0(0x%lx)\n", (long)function));
420 return call_into_lisp(function, args, 0);
423 funcall1(lispobj function, lispobj arg0)
427 return call_into_lisp(function, args, 1);
430 funcall2(lispobj function, lispobj arg0, lispobj arg1)
435 return call_into_lisp(function, args, 2);
438 funcall3(lispobj function, lispobj arg0, lispobj arg1, lispobj arg2)
444 return call_into_lisp(function, args, 3);
448 #ifdef LISP_FEATURE_LINKAGE_TABLE
449 /* FIXME: It might be cleaner to generate these from the lisp side of
454 arch_write_linkage_table_jmp(char * reloc, void * fun)
456 unsigned long addr = (unsigned long) fun;
459 *reloc++ = 0xFF; /* Opcode for near jump to absolute reg/mem64. */
460 *reloc++ = 0x25; /* ModRM #b00 100 101, i.e. RIP-relative. */
461 *reloc++ = 0x00; /* 32-bit displacement field = 0 */
462 *reloc++ = 0x00; /* ... */
463 *reloc++ = 0x00; /* ... */
464 *reloc++ = 0x00; /* ... */
466 for (i = 0; i < 8; i++) {
467 *reloc++ = addr & 0xff;
471 /* write a nop for good measure. */
476 arch_write_linkage_table_ref(void * reloc, void * data)
478 *(unsigned long *)reloc = (unsigned long)data;
483 /* These setup and check *both* the sse2 and x87 FPUs. While lisp code
484 only uses the sse2 FPU, other code (such as libc) may use the x87 FPU.
492 /* return the x87 exception flags ored in with the sse2
493 * control+status flags */
494 asm ("fnstsw %0" : "=m" (temp));
497 asm ("stmxcsr %0" : "=m" (temp));
499 /* flip exception mask bits */
500 return result ^ (0x3F << 7);
506 unsigned short unused1;
508 unsigned short unused2;
509 unsigned int other_regs[5];
513 arch_set_fp_modes(unsigned int mxcsr)
518 /* turn trap enable bits into exception mask */
522 asm ("fnstenv %0" : "=m" (f_env));
523 /* set control word: always long double precision
524 * get traps and rounding from mxcsr word */
525 f_env.cw = 0x300 | ((mxcsr >> 7) & 0x3F) | (((mxcsr >> 13) & 0x3) << 10);
526 /* set status word: only override exception flags, from mxcsr */
528 f_env.sw |= (mxcsr & 0x3F);
530 asm ("fldenv %0" : : "m" (f_env));
532 /* now, simply, load up the mxcsr register */
534 asm ("ldmxcsr %0" : : "m" (temp));