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"
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.)
54 context_eflags_addr(os_context_t *context)
56 #if defined __linux__ || defined __sun
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[16];
63 #elif defined __FreeBSD__
64 return &context->uc_mcontext.mc_eflags;
65 #elif defined __OpenBSD__
66 return &context->sc_eflags;
67 #elif defined __NetBSD__
68 return &(context->uc_mcontext.__gregs[_REG_EFL]);
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 /* only needed to skip the Code */
109 fprintf(stderr,"[arch_skip_inst invalid code %d\n]\n",code);
114 "/[arch_skip_inst resuming at %x]\n",
115 *os_context_pc_addr(context)));
119 arch_internal_error_arguments(os_context_t *context)
121 return 1 + (unsigned char *)(*os_context_pc_addr(context));
125 arch_pseudo_atomic_atomic(os_context_t *context)
127 return SymbolValue(PSEUDO_ATOMIC_ATOMIC,arch_os_get_current_thread());
131 arch_set_pseudo_atomic_interrupted(os_context_t *context)
133 SetSymbolValue(PSEUDO_ATOMIC_INTERRUPTED, make_fixnum(1),
134 arch_os_get_current_thread());
138 * This stuff seems to get called for TRACE and debug activity.
142 arch_install_breakpoint(void *pc)
144 unsigned int result = *(unsigned int*)pc;
146 *(char*)pc = BREAKPOINT_INST; /* x86 INT3 */
147 *((char*)pc+1) = trap_Breakpoint; /* Lisp trap code */
153 arch_remove_breakpoint(void *pc, unsigned int orig_inst)
155 *((char *)pc) = orig_inst & 0xff;
156 *((char *)pc + 1) = (orig_inst & 0xff00) >> 8;
159 /* When single stepping, single_stepping holds the original instruction
161 unsigned int *single_stepping = NULL;
162 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
163 unsigned int single_step_save1;
164 unsigned int single_step_save2;
165 unsigned int single_step_save3;
169 arch_do_displaced_inst(os_context_t *context, unsigned int orig_inst)
171 unsigned int *pc = (unsigned int*)(*os_context_pc_addr(context));
173 /* Put the original instruction back. */
174 *((char *)pc) = orig_inst & 0xff;
175 *((char *)pc + 1) = (orig_inst & 0xff00) >> 8;
177 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
178 /* Install helper instructions for the single step:
179 * pushf; or [esp],0x100; popf. */
180 single_step_save1 = *(pc-3);
181 single_step_save2 = *(pc-2);
182 single_step_save3 = *(pc-1);
183 *(pc-3) = 0x9c909090;
184 *(pc-2) = 0x00240c81;
185 *(pc-1) = 0x9d000001;
187 *context_eflags_addr(context) |= 0x100;
190 single_stepping = pc;
192 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
193 *os_context_pc_addr(context) = (char *)pc - 9;
198 sigtrap_handler(int signal, siginfo_t *info, void *void_context)
200 int code = info->si_code;
201 os_context_t *context = (os_context_t*)void_context;
204 if (single_stepping && (signal==SIGTRAP))
206 /* fprintf(stderr,"* single step trap %x\n", single_stepping); */
208 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
209 /* Un-install single step helper instructions. */
210 *(single_stepping-3) = single_step_save1;
211 *(single_stepping-2) = single_step_save2;
212 *(single_stepping-1) = single_step_save3;
214 *context_eflags_addr(context) ^= 0x100;
216 /* Re-install the breakpoint if possible. */
217 if (*os_context_pc_addr(context) == (int)single_stepping + 1) {
218 fprintf(stderr, "warning: couldn't reinstall breakpoint\n");
220 *((char *)single_stepping) = BREAKPOINT_INST; /* x86 INT3 */
221 *((char *)single_stepping+1) = trap_Breakpoint;
224 single_stepping = NULL;
228 /* This is just for info in case the monitor wants to print an
230 current_control_stack_pointer =
231 (lispobj *)*os_context_sp_addr(context);
233 /* FIXME: CMUCL puts the float control restoration code here.
234 Thus, it seems to me that single-stepping won't restore the
235 float control. Since SBCL currently doesn't support
236 single-stepping (as far as I can tell) this is somewhat moot,
237 but it might be worth either moving this code up or deleting
238 the single-stepping code entirely. -- CSR, 2002-07-15 */
239 #ifdef LISP_FEATURE_LINUX
240 os_restore_fp_control(context);
243 /* On entry %eip points just after the INT3 byte and aims at the
244 * 'kind' value (eg trap_Cerror). For error-trap and Cerror-trap a
245 * number of bytes will follow, the first is the length of the byte
246 * arguments to follow. */
247 trap = *(unsigned char *)(*os_context_pc_addr(context));
250 case trap_PendingInterrupt:
251 FSHOW((stderr, "/<trap pending interrupt>\n"));
252 arch_skip_instruction(context);
253 interrupt_handle_pending(context);
257 /* Note: the old CMU CL code tried to save FPU state
258 * here, and restore it after we do our thing, but there
259 * seems to be no point in doing that, since we're just
260 * going to lose(..) anyway. */
261 fake_foreign_function_call(context);
262 lose("%%PRIMITIVE HALT called; the party is over.");
266 FSHOW((stderr, "<trap error/cerror %d>\n", code));
267 interrupt_internal_error(signal, info, context, code==trap_Cerror);
270 case trap_Breakpoint:
271 --*os_context_pc_addr(context);
272 handle_breakpoint(signal, info, context);
275 case trap_FunEndBreakpoint:
276 --*os_context_pc_addr(context);
277 *os_context_pc_addr(context) =
278 (int)handle_fun_end_breakpoint(signal, info, context);
282 FSHOW((stderr,"/[C--trap default %d %d %x]\n",
283 signal, code, context));
284 interrupt_handle_now(signal, info, context);
290 sigill_handler(int signal, siginfo_t *siginfo, void *void_context) {
291 os_context_t *context = (os_context_t*)void_context;
292 fake_foreign_function_call(context);
293 monitor_or_something();
297 arch_install_interrupt_handlers()
299 SHOW("entering arch_install_interrupt_handlers()");
301 /* Note: The old CMU CL code here used sigtrap_handler() to handle
302 * SIGILL as well as SIGTRAP. I couldn't see any reason to do
303 * things that way. So, I changed to separate handlers when
304 * debugging a problem on OpenBSD, where SBCL wasn't catching
305 * SIGILL properly, but was instead letting the process be
306 * terminated with an "Illegal instruction" output. If this change
307 * turns out to break something (maybe breakpoint handling on some
308 * OS I haven't tested on?) and we have to go back to the old CMU
309 * CL way, I hope there will at least be a comment to explain
310 * why.. -- WHN 2001-06-07 */
311 undoably_install_low_level_interrupt_handler(SIGILL , sigill_handler);
312 undoably_install_low_level_interrupt_handler(SIGTRAP, sigtrap_handler);
314 SHOW("returning from arch_install_interrupt_handlers()");
317 /* This is implemented in assembly language and called from C: */
319 call_into_lisp(lispobj fun, lispobj *args, int nargs);
321 /* These functions are an interface to the Lisp call-in facility.
322 * Since this is C we can know nothing about the calling environment.
323 * The control stack might be the C stack if called from the monitor
324 * or the Lisp stack if called as a result of an interrupt or maybe
325 * even a separate stack. The args are most likely on that stack but
326 * could be in registers depending on what the compiler likes. So we
327 * copy the args into a portable vector and let the assembly language
328 * call-in function figure it out. */
331 funcall0(lispobj function)
333 lispobj *args = NULL;
335 FSHOW((stderr, "/entering funcall0(0x%lx)\n", (long)function));
336 return call_into_lisp(function, args, 0);
339 funcall1(lispobj function, lispobj arg0)
343 return call_into_lisp(function, args, 1);
346 funcall2(lispobj function, lispobj arg0, lispobj arg1)
351 return call_into_lisp(function, args, 2);
354 funcall3(lispobj function, lispobj arg0, lispobj arg1, lispobj arg2)
360 return call_into_lisp(function, args, 3);
363 #ifdef LISP_FEATURE_LINKAGE_TABLE
364 /* FIXME: It might be cleaner to generate these from the lisp side of
369 arch_write_linkage_table_jmp(char * reloc, void * fun)
371 /* Make JMP to function entry. JMP offset is calculated from next
374 long offset = (char *)fun - (reloc + 5);
377 *reloc++ = 0xe9; /* opcode for JMP rel32 */
378 for (i = 0; i < 4; i++) {
379 *reloc++ = offset & 0xff;
383 /* write a nop for good measure. */
388 arch_write_linkage_table_ref(void * reloc, void * data)
390 *(unsigned long *)reloc = (unsigned long)data;