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"
30 #include "genesis/static-symbols.h"
31 #include "genesis/symbol.h"
33 #define BREAKPOINT_INST 0xcc /* INT3 */
35 unsigned long fast_random_state = 1;
41 arch_get_bad_addr(int sig, siginfo_t *code, os_context_t *context)
43 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)
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[17];
64 #elif defined __FreeBSD__
65 return &context->uc_mcontext.mc_eflags;
66 #elif defined __OpenBSD__
67 return &context->sc_eflags;
73 void arch_skip_instruction(os_context_t *context)
75 /* Assuming we get here via an INT3 xxx instruction, the PC now
76 * points to the interrupt code (a Lisp value) so we just move
77 * past it. Skip the code; after that, if the code is an
78 * error-trap or cerror-trap then skip the data bytes that follow. */
84 /* Get and skip the Lisp interrupt code. */
85 code = *(char*)(*os_context_pc_addr(context))++;
90 /* Lisp error arg vector length */
91 vlen = *(char*)(*os_context_pc_addr(context))++;
92 /* Skip Lisp error arg data bytes. */
94 ++*os_context_pc_addr(context);
98 case trap_Breakpoint: /* not tested */
99 case trap_FunEndBreakpoint: /* not tested */
102 case trap_PendingInterrupt:
104 /* only needed to skip the Code */
108 fprintf(stderr,"[arch_skip_inst invalid code %d\n]\n",code);
113 "/[arch_skip_inst resuming at %x]\n",
114 *os_context_pc_addr(context)));
118 arch_internal_error_arguments(os_context_t *context)
120 return 1 + (unsigned char *)(*os_context_pc_addr(context));
124 arch_pseudo_atomic_atomic(os_context_t *context)
126 return SymbolValue(PSEUDO_ATOMIC_ATOMIC,arch_os_get_current_thread());
130 arch_set_pseudo_atomic_interrupted(os_context_t *context)
132 SetSymbolValue(PSEUDO_ATOMIC_INTERRUPTED, make_fixnum(1),
133 arch_os_get_current_thread());
137 arch_clear_pseudo_atomic_interrupted(os_context_t *context)
139 SetSymbolValue(PSEUDO_ATOMIC_INTERRUPTED, make_fixnum(0),
140 arch_os_get_current_thread());
144 * This stuff seems to get called for TRACE and debug activity.
148 arch_install_breakpoint(void *pc)
150 unsigned int result = *(unsigned int*)pc;
152 *(char*)pc = BREAKPOINT_INST; /* x86 INT3 */
153 *((char*)pc+1) = trap_Breakpoint; /* Lisp trap code */
159 arch_remove_breakpoint(void *pc, unsigned int orig_inst)
161 *((char *)pc) = orig_inst & 0xff;
162 *((char *)pc + 1) = (orig_inst & 0xff00) >> 8;
165 /* When single stepping, single_stepping holds the original instruction
167 unsigned int *single_stepping = NULL;
168 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
169 unsigned long single_step_save1;
170 unsigned long single_step_save2;
171 unsigned long single_step_save3;
175 arch_do_displaced_inst(os_context_t *context, unsigned int orig_inst)
177 unsigned int *pc = (unsigned int*)(*os_context_pc_addr(context));
179 /* Put the original instruction back. */
180 *((char *)pc) = orig_inst & 0xff;
181 *((char *)pc + 1) = (orig_inst & 0xff00) >> 8;
183 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
184 /* Install helper instructions for the single step:
185 * pushf; or [esp],0x100; popf. */
186 single_step_save1 = *(pc-3);
187 single_step_save2 = *(pc-2);
188 single_step_save3 = *(pc-1);
189 *(pc-3) = 0x9c909090;
190 *(pc-2) = 0x00240c81;
191 *(pc-1) = 0x9d000001;
193 *context_eflags_addr(context) |= 0x100;
196 single_stepping = pc;
198 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
199 *os_context_pc_addr(context) = (char *)pc - 9;
204 sigtrap_handler(int signal, siginfo_t *info, void *void_context)
206 int code = info->si_code;
207 os_context_t *context = (os_context_t*)void_context;
210 if (single_stepping && (signal==SIGTRAP))
212 /* fprintf(stderr,"* single step trap %x\n", single_stepping); */
214 #ifdef CANNOT_GET_TO_SINGLE_STEP_FLAG
215 /* Un-install single step helper instructions. */
216 *(single_stepping-3) = single_step_save1;
217 *(single_stepping-2) = single_step_save2;
218 *(single_stepping-1) = single_step_save3;
220 *context_eflags_addr(context) ^= 0x100;
222 /* Re-install the breakpoint if possible. */
223 if (*os_context_pc_addr(context) == (int)single_stepping + 1) {
224 fprintf(stderr, "warning: couldn't reinstall breakpoint\n");
226 *((char *)single_stepping) = BREAKPOINT_INST; /* x86 INT3 */
227 *((char *)single_stepping+1) = trap_Breakpoint;
230 single_stepping = NULL;
234 /* This is just for info in case the monitor wants to print an
236 current_control_stack_pointer =
237 (lispobj *)*os_context_sp_addr(context);
239 /* FIXME: CMUCL puts the float control restoration code here.
240 Thus, it seems to me that single-stepping won't restore the
241 float control. Since SBCL currently doesn't support
242 single-stepping (as far as I can tell) this is somewhat moot,
243 but it might be worth either moving this code up or deleting
244 the single-stepping code entirely. -- CSR, 2002-07-15 */
245 #ifdef LISP_FEATURE_LINUX
246 os_restore_fp_control(context);
249 /* On entry %eip points just after the INT3 byte and aims at the
250 * 'kind' value (eg trap_Cerror). For error-trap and Cerror-trap a
251 * number of bytes will follow, the first is the length of the byte
252 * arguments to follow. */
253 trap = *(unsigned char *)(*os_context_pc_addr(context));
256 case trap_PendingInterrupt:
257 FSHOW((stderr, "/<trap pending interrupt>\n"));
258 arch_skip_instruction(context);
259 interrupt_handle_pending(context);
263 /* Note: the old CMU CL code tried to save FPU state
264 * here, and restore it after we do our thing, but there
265 * seems to be no point in doing that, since we're just
266 * going to lose(..) anyway. */
267 fake_foreign_function_call(context);
268 lose("%%PRIMITIVE HALT called; the party is over.");
272 FSHOW((stderr, "<trap error/cerror %d>\n", code));
273 interrupt_internal_error(signal, info, context, code==trap_Cerror);
276 case trap_Breakpoint:
277 --*os_context_pc_addr(context);
278 handle_breakpoint(signal, info, context);
281 case trap_FunEndBreakpoint:
282 --*os_context_pc_addr(context);
283 *os_context_pc_addr(context) =
284 (unsigned long)handle_fun_end_breakpoint(signal, info, context);
288 FSHOW((stderr,"/[C--trap default %d %d %x]\n",
289 signal, code, context));
290 interrupt_handle_now(signal, info, context);
296 sigill_handler(int signal, siginfo_t *siginfo, void *void_context) {
297 os_context_t *context = (os_context_t*)void_context;
298 fake_foreign_function_call(context);
299 monitor_or_something();
303 arch_install_interrupt_handlers()
305 SHOW("entering arch_install_interrupt_handlers()");
307 /* Note: The old CMU CL code here used sigtrap_handler() to handle
308 * SIGILL as well as SIGTRAP. I couldn't see any reason to do
309 * things that way. So, I changed to separate handlers when
310 * debugging a problem on OpenBSD, where SBCL wasn't catching
311 * SIGILL properly, but was instead letting the process be
312 * terminated with an "Illegal instruction" output. If this change
313 * turns out to break something (maybe breakpoint handling on some
314 * OS I haven't tested on?) and we have to go back to the old CMU
315 * CL way, I hope there will at least be a comment to explain
316 * why.. -- WHN 2001-06-07 */
317 undoably_install_low_level_interrupt_handler(SIGILL , sigill_handler);
318 undoably_install_low_level_interrupt_handler(SIGTRAP, sigtrap_handler);
320 SHOW("returning from arch_install_interrupt_handlers()");
323 /* This is implemented in assembly language and called from C: */
325 call_into_lisp(lispobj fun, lispobj *args, int nargs);
327 /* These functions are an interface to the Lisp call-in facility.
328 * Since this is C we can know nothing about the calling environment.
329 * The control stack might be the C stack if called from the monitor
330 * or the Lisp stack if called as a result of an interrupt or maybe
331 * even a separate stack. The args are most likely on that stack but
332 * could be in registers depending on what the compiler likes. So we
333 * copy the args into a portable vector and let the assembly language
334 * call-in function figure it out. */
337 funcall0(lispobj function)
339 lispobj *args = NULL;
341 FSHOW((stderr, "/entering funcall0(0x%lx)\n", (long)function));
342 return call_into_lisp(function, args, 0);
345 funcall1(lispobj function, lispobj arg0)
349 return call_into_lisp(function, args, 1);
352 funcall2(lispobj function, lispobj arg0, lispobj arg1)
357 return call_into_lisp(function, args, 2);
360 funcall3(lispobj function, lispobj arg0, lispobj arg1, lispobj arg2)
366 return call_into_lisp(function, args, 3);
370 #ifdef LISP_FEATURE_LINKAGE_TABLE
371 /* FIXME: It might be cleaner to generate these from the lisp side of
376 arch_write_linkage_table_jmp(char * reloc, void * fun)
378 unsigned long addr = (unsigned long) fun;
381 *reloc++ = 0xFF; /* Opcode for near jump to absolute reg/mem64. */
382 *reloc++ = 0x25; /* ModRM #b00 100 101, i.e. RIP-relative. */
383 *reloc++ = 0x00; /* 32-bit displacement field = 0 */
384 *reloc++ = 0x00; /* ... */
385 *reloc++ = 0x00; /* ... */
386 *reloc++ = 0x00; /* ... */
388 for (i = 0; i < 8; i++) {
389 *reloc++ = addr & 0xff;
393 /* write a nop for good measure. */
398 arch_write_linkage_table_ref(void * reloc, void * data)
400 *(unsigned long *)reloc = (unsigned long)data;
405 /* These setup and check *both* the sse2 and x87 FPUs. While lisp code
406 only uses the sse2 FPU, other code (such as libc) may use the x87 FPU.
414 /* return the x87 exception flags ored in with the sse2
415 * control+status flags */
416 asm ("fnstsw %0" : "=m" (temp));
419 asm ("stmxcsr %0" : "=m" (temp));
421 /* flip exception mask bits */
422 return result ^ (0x3F << 7);
428 unsigned short unused1;
430 unsigned short unused2;
431 unsigned int other_regs[5];
435 arch_set_fp_modes(unsigned int mxcsr)
440 /* turn trap enable bits into exception mask */
444 asm ("fnstenv %0" : "=m" (f_env));
445 /* set control word: always long double precision
446 * get traps and rounding from mxcsr word */
447 f_env.cw = 0x300 | ((mxcsr >> 7) & 0x3F) | (((mxcsr >> 13) & 0x3) << 10);
448 /* set status word: only override exception flags, from mxcsr */
450 f_env.sw |= (mxcsr & 0x3F);
452 asm ("fldenv %0" : : "m" (f_env));
454 /* now, simply, load up the mxcsr register */
456 asm ("ldmxcsr %0" : : "m" (temp));