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.
23 #include "interrupt.h"
25 #include "breakpoint.h"
28 #include "genesis/static-symbols.h"
29 #include "genesis/symbol.h"
31 #define BREAKPOINT_INST 0xcc /* INT3 */
33 unsigned long fast_random_state = 1;
38 #ifndef LISP_FEATURE_WIN32
40 arch_get_bad_addr(int sig, siginfo_t *code, os_context_t *context)
42 return (os_vm_address_t)code->si_addr;
48 * hacking signal contexts
50 * (This depends both on architecture, which determines what we might
51 * want to get to, and on OS, which determines how we get to it.)
55 context_eflags_addr(os_context_t *context)
57 #if defined __linux__ || defined __sun
58 /* KLUDGE: As of kernel 2.2.14 on Red Hat 6.2, there's code in the
59 * <sys/ucontext.h> file to define symbolic names for offsets into
60 * gregs[], but it's conditional on __USE_GNU and not defined, so
61 * we need to do this nasty absolute index magic number thing
63 return &context->uc_mcontext.gregs[16];
64 #elif defined __FreeBSD__
65 return &context->uc_mcontext.mc_eflags;
66 #elif defined __OpenBSD__
67 return &context->sc_eflags;
68 #elif defined LISP_FEATURE_DARWIN
69 return &context->uc_mcontext->ss.eflags;
70 #elif defined __NetBSD__
71 return &(context->uc_mcontext.__gregs[_REG_EFL]);
72 #elif defined LISP_FEATURE_WIN32
73 return (int *)&context->EFlags;
79 void arch_skip_instruction(os_context_t *context)
81 /* Assuming we get here via an INT3 xxx instruction, the PC now
82 * points to the interrupt code (a Lisp value) so we just move
83 * past it. Skip the code; after that, if the code is an
84 * error-trap or cerror-trap then skip the data bytes that follow. */
90 /* Get and skip the Lisp interrupt code. */
91 code = *(char*)(*os_context_pc_addr(context))++;
96 /* Lisp error arg vector length */
97 vlen = *(char*)(*os_context_pc_addr(context))++;
98 /* Skip Lisp error arg data bytes. */
100 ++*os_context_pc_addr(context);
104 case trap_Breakpoint: /* not tested */
105 case trap_FunEndBreakpoint: /* not tested */
108 case trap_PendingInterrupt:
110 /* only needed to skip the Code */
114 fprintf(stderr,"[arch_skip_inst invalid code %d\n]\n",code);
119 "/[arch_skip_inst resuming at %x]\n",
120 *os_context_pc_addr(context)));
124 arch_internal_error_arguments(os_context_t *context)
126 return 1 + (unsigned char *)(*os_context_pc_addr(context));
130 arch_pseudo_atomic_atomic(os_context_t *context)
132 return SymbolValue(PSEUDO_ATOMIC_ATOMIC,arch_os_get_current_thread());
136 arch_set_pseudo_atomic_interrupted(os_context_t *context)
138 SetSymbolValue(PSEUDO_ATOMIC_INTERRUPTED, make_fixnum(1),
139 arch_os_get_current_thread());
143 arch_clear_pseudo_atomic_interrupted(os_context_t *context)
145 SetSymbolValue(PSEUDO_ATOMIC_INTERRUPTED, make_fixnum(0),
146 arch_os_get_current_thread());
150 * This stuff seems to get called for TRACE and debug activity.
154 arch_install_breakpoint(void *pc)
156 unsigned int result = *(unsigned int*)pc;
158 *(char*)pc = BREAKPOINT_INST; /* x86 INT3 */
159 *((char*)pc+1) = trap_Breakpoint; /* Lisp trap code */
165 arch_remove_breakpoint(void *pc, unsigned int orig_inst)
167 *((char *)pc) = orig_inst & 0xff;
168 *((char *)pc + 1) = (orig_inst & 0xff00) >> 8;
171 /* When single stepping, single_stepping holds the original instruction
173 unsigned int *single_stepping = NULL;
174 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
175 unsigned int single_step_save1;
176 unsigned int single_step_save2;
177 unsigned int single_step_save3;
181 arch_do_displaced_inst(os_context_t *context, unsigned int orig_inst)
183 unsigned int *pc = (unsigned int*)(*os_context_pc_addr(context));
185 /* Put the original instruction back. */
186 *((char *)pc) = orig_inst & 0xff;
187 *((char *)pc + 1) = (orig_inst & 0xff00) >> 8;
189 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
190 /* Install helper instructions for the single step:
191 * pushf; or [esp],0x100; popf. */
192 single_step_save1 = *(pc-3);
193 single_step_save2 = *(pc-2);
194 single_step_save3 = *(pc-1);
195 *(pc-3) = 0x9c909090;
196 *(pc-2) = 0x00240c81;
197 *(pc-1) = 0x9d000001;
199 *context_eflags_addr(context) |= 0x100;
202 single_stepping = pc;
204 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
205 *os_context_pc_addr(context) = (char *)pc - 9;
210 sigtrap_handler(int signal, siginfo_t *info, void *void_context)
212 os_context_t *context = (os_context_t*)void_context;
215 #ifndef LISP_FEATURE_WIN32
216 if (single_stepping && (signal==SIGTRAP))
218 /* fprintf(stderr,"* single step trap %x\n", single_stepping); */
220 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
221 /* Un-install single step helper instructions. */
222 *(single_stepping-3) = single_step_save1;
223 *(single_stepping-2) = single_step_save2;
224 *(single_stepping-1) = single_step_save3;
226 *context_eflags_addr(context) &= ~0x100;
228 /* Re-install the breakpoint if possible. */
229 if (*os_context_pc_addr(context) == (int)single_stepping + 1) {
230 fprintf(stderr, "warning: couldn't reinstall breakpoint\n");
232 *((char *)single_stepping) = BREAKPOINT_INST; /* x86 INT3 */
233 *((char *)single_stepping+1) = trap_Breakpoint;
236 single_stepping = NULL;
241 /* This is just for info in case the monitor wants to print an
243 current_control_stack_pointer =
244 (lispobj *)*os_context_sp_addr(context);
246 /* FIXME: CMUCL puts the float control restoration code here.
247 Thus, it seems to me that single-stepping won't restore the
248 float control. Since SBCL currently doesn't support
249 single-stepping (as far as I can tell) this is somewhat moot,
250 but it might be worth either moving this code up or deleting
251 the single-stepping code entirely. -- CSR, 2002-07-15 */
252 #if defined(LISP_FEATURE_LINUX) || defined(RESTORE_FP_CONTROL_FROM_CONTEXT)
253 os_restore_fp_control(context);
257 #ifdef LISP_FEATURE_SUNOS
258 /* For some reason the breakpoints that :ENCAPSULATE NIL tracing sets up
259 * cause a trace trap (i.e. processor single-stepping trap) on the following
260 * instruction on Solaris 10/x86. -- JES, 2006-04-07
262 if (info->si_code == TRAP_TRACE) {
268 /* On entry %eip points just after the INT3 byte and aims at the
269 * 'kind' value (eg trap_Cerror). For error-trap and Cerror-trap a
270 * number of bytes will follow, the first is the length of the byte
271 * arguments to follow. */
272 trap = *(unsigned char *)(*os_context_pc_addr(context));
273 /* FSHOW((stderr, "/<sigtrap trap %d at pc_addr: %p>\n", trap, *os_context_pc_addr(context))); */
276 case trap_PendingInterrupt:
277 FSHOW((stderr, "/<trap pending interrupt>\n"));
278 arch_skip_instruction(context);
279 interrupt_handle_pending(context);
283 /* Note: the old CMU CL code tried to save FPU state
284 * here, and restore it after we do our thing, but there
285 * seems to be no point in doing that, since we're just
286 * going to lose(..) anyway. */
287 fake_foreign_function_call(context);
288 lose("%%PRIMITIVE HALT called; the party is over.\n");
292 FSHOW((stderr, "<trap error/cerror %d>\n", trap));
293 interrupt_internal_error(signal, info, context, trap==trap_Cerror);
296 case trap_Breakpoint:
297 --*os_context_pc_addr(context);
298 handle_breakpoint(signal, info, context);
301 case trap_FunEndBreakpoint:
302 --*os_context_pc_addr(context);
303 *os_context_pc_addr(context) =
304 (int)handle_fun_end_breakpoint(signal, info, context);
308 FSHOW((stderr,"/[C--trap default %d %d %x]\n",
309 signal, trap, context));
310 interrupt_handle_now(signal, info, context);
316 sigill_handler(int signal, siginfo_t *siginfo, void *void_context) {
317 os_context_t *context = (os_context_t*)void_context;
319 /* Triggering SIGTRAP using int3 is unreliable on OS X/x86, so
320 * we need to use illegal instructions for traps.
322 #if defined(LISP_FEATURE_DARWIN)
323 if (*((unsigned short *)*os_context_pc_addr(context)) == 0x0b0f) {
324 *os_context_pc_addr(context) += 2;
325 return sigtrap_handler(signal, siginfo, void_context);
329 fake_foreign_function_call(context);
330 lose("fake_foreign_call fell through");
334 arch_install_interrupt_handlers()
336 SHOW("entering arch_install_interrupt_handlers()");
338 /* Note: The old CMU CL code here used sigtrap_handler() to handle
339 * SIGILL as well as SIGTRAP. I couldn't see any reason to do
340 * things that way. So, I changed to separate handlers when
341 * debugging a problem on OpenBSD, where SBCL wasn't catching
342 * SIGILL properly, but was instead letting the process be
343 * terminated with an "Illegal instruction" output. If this change
344 * turns out to break something (maybe breakpoint handling on some
345 * OS I haven't tested on?) and we have to go back to the old CMU
346 * CL way, I hope there will at least be a comment to explain
347 * why.. -- WHN 2001-06-07 */
348 #ifndef LISP_FEATURE_WIN32
349 undoably_install_low_level_interrupt_handler(SIGILL , sigill_handler);
350 undoably_install_low_level_interrupt_handler(SIGTRAP, sigtrap_handler);
353 SHOW("returning from arch_install_interrupt_handlers()");
356 /* This is implemented in assembly language and called from C: */
358 call_into_lisp(lispobj fun, lispobj *args, int nargs);
360 /* These functions are an interface to the Lisp call-in facility.
361 * Since this is C we can know nothing about the calling environment.
362 * The control stack might be the C stack if called from the monitor
363 * or the Lisp stack if called as a result of an interrupt or maybe
364 * even a separate stack. The args are most likely on that stack but
365 * could be in registers depending on what the compiler likes. So we
366 * copy the args into a portable vector and let the assembly language
367 * call-in function figure it out. */
370 funcall0(lispobj function)
372 lispobj *args = NULL;
374 FSHOW((stderr, "/entering funcall0(0x%lx)\n", (long)function));
375 return call_into_lisp(function, args, 0);
378 funcall1(lispobj function, lispobj arg0)
382 return call_into_lisp(function, args, 1);
385 funcall2(lispobj function, lispobj arg0, lispobj arg1)
390 return call_into_lisp(function, args, 2);
393 funcall3(lispobj function, lispobj arg0, lispobj arg1, lispobj arg2)
399 return call_into_lisp(function, args, 3);
402 #ifdef LISP_FEATURE_LINKAGE_TABLE
403 /* FIXME: It might be cleaner to generate these from the lisp side of
408 arch_write_linkage_table_jmp(char * reloc, void * fun)
410 /* Make JMP to function entry. JMP offset is calculated from next
413 long offset = (char *)fun - (reloc + 5);
416 *reloc++ = 0xe9; /* opcode for JMP rel32 */
417 for (i = 0; i < 4; i++) {
418 *reloc++ = offset & 0xff;
422 /* write a nop for good measure. */
427 arch_write_linkage_table_ref(void * reloc, void * data)
429 *(unsigned long *)reloc = (unsigned long)data;