Actual source code: fp.c
1: /*
2: IEEE error handler for all machines. Since each OS has
3: enough slight differences we have completely separate codes for each one.
4: */
6: /*
7: This feature test macro provides FE_NOMASK_ENV on GNU. It must be defined
8: at the top of the file because other headers may pull in fenv.h even when
9: not strictly necessary. Strictly speaking, we could include ONLY petscconf.h,
10: check PETSC_HAVE_FENV_H, and only define _GNU_SOURCE in that case, but such
11: shenanigans ought to be unnecessary.
12: */
13: #if !defined(_GNU_SOURCE)
14: #define _GNU_SOURCE
15: #endif
17: #include <petsc/private/petscimpl.h>
18: #include <signal.h>
19: #if defined(PETSC_HAVE_XMMINTRIN_H)
20: #include <xmmintrin.h>
21: #endif
23: struct PetscFPTrapLink {
24: PetscFPTrap trapmode;
25: struct PetscFPTrapLink *next;
26: };
27: static PetscFPTrap _trapmode = PETSC_FP_TRAP_OFF; /* Current trapping mode; see PetscDetermineInitialFPTrap() */
28: static struct PetscFPTrapLink *_trapstack; /* Any pushed states of _trapmode */
30: /*@
31: PetscFPTrapPush - push a floating point trapping mode, restored using `PetscFPTrapPop()`
33: Not Collective
35: Input Parameter:
36: . trap - `PETSC_FP_TRAP_ON` or `PETSC_FP_TRAP_OFF` or any of the values passable to `PetscSetFPTrap()`
38: Level: advanced
40: Notes:
41: This only changes the trapping if the new mode is different than the current mode.
43: This routine is called to turn off trapping for certain LAPACK routines that assume that dividing
44: by zero is acceptable. In particular the routine ieeeck().
46: Most systems by default have all trapping turned off, but certain Fortran compilers have
47: link flags that turn on trapping before the program begins.
48: .vb
49: gfortran -ffpe-trap=invalid,zero,overflow,underflow,denormal
50: ifort -fpe0
51: .ve
53: .seealso: `PetscFPTrapPop()`, `PetscSetFPTrap()`, `PetscDetermineInitialFPTrap()`
54: @*/
55: PetscErrorCode PetscFPTrapPush(PetscFPTrap trap)
56: {
57: struct PetscFPTrapLink *link;
59: PetscFunctionBegin;
60: PetscCall(PetscNew(&link));
61: #if defined(PETSC_HAVE_THREADSAFETY) && defined(PETSC_HAVE_OPENMP)
62: PetscPragmaOMP(critical)
63: #endif
64: {
65: link->trapmode = _trapmode;
66: link->next = _trapstack;
67: _trapstack = link;
68: }
69: if (trap != _trapmode) PetscCall(PetscSetFPTrap(trap));
70: PetscFunctionReturn(PETSC_SUCCESS);
71: }
73: /*@
74: PetscFPTrapPop - push a floating point trapping mode, to be restored using `PetscFPTrapPop()`
76: Not Collective
78: Level: advanced
80: .seealso: `PetscFPTrapPush()`, `PetscSetFPTrap()`, `PetscDetermineInitialFPTrap()`
81: @*/
82: PetscErrorCode PetscFPTrapPop(void)
83: {
84: struct PetscFPTrapLink *link;
86: PetscFunctionBegin;
87: if (_trapstack->trapmode != _trapmode) PetscCall(PetscSetFPTrap(_trapstack->trapmode));
88: #if defined(PETSC_HAVE_THREADSAFETY) && defined(PETSC_HAVE_OPENMP)
89: PetscPragmaOMP(critical)
90: #endif
91: {
92: link = _trapstack;
93: _trapstack = _trapstack->next;
94: }
95: PetscCall(PetscFree(link));
96: PetscFunctionReturn(PETSC_SUCCESS);
97: }
99: /*--------------------------------------- ---------------------------------------------------*/
100: #if defined(PETSC_HAVE_SUN4_STYLE_FPTRAP)
101: #include <floatingpoint.h>
103: PETSC_EXTERN PetscErrorCode ieee_flags(char *, char *, char *, char **);
104: PETSC_EXTERN PetscErrorCode ieee_handler(char *, char *, sigfpe_handler_type(int, int, struct sigcontext *, char *));
106: static struct {
107: int code_no;
108: char *name;
109: } error_codes[] = {
110: {FPE_INTDIV_TRAP, "integer divide" },
111: {FPE_FLTOPERR_TRAP, "IEEE operand error" },
112: {FPE_FLTOVF_TRAP, "floating point overflow" },
113: {FPE_FLTUND_TRAP, "floating point underflow" },
114: {FPE_FLTDIV_TRAP, "floating pointing divide" },
115: {FPE_FLTINEX_TRAP, "inexact floating point result"},
116: {0, "unknown error" }
117: };
118: #define SIGPC(scp) (scp->sc_pc)
120: /* this function gets called if a trap has occurred and been caught */
121: sigfpe_handler_type PetscDefaultFPTrap(int sig, int code, struct sigcontext *scp, char *addr)
122: {
123: int err_ind = -1;
125: PetscFunctionBegin;
126: for (int j = 0; error_codes[j].code_no; j++) {
127: if (error_codes[j].code_no == code) err_ind = j;
128: }
130: if (err_ind >= 0) (void)(*PetscErrorPrintf)("*** %s occurred at pc=%X ***\n", error_codes[err_ind].name, SIGPC(scp));
131: else (void)(*PetscErrorPrintf)("*** floating point error 0x%x occurred at pc=%X ***\n", code, SIGPC(scp));
133: (void)PetscError(PETSC_COMM_SELF, PETSC_ERR_FP, NULL, NULL, PETSC_ERR_FP, PETSC_ERROR_REPEAT, "floating point error");
134: PETSCABORT(MPI_COMM_WORLD, PETSC_ERR_FP);
135: PetscFunctionReturn(PETSC_SUCCESS);
136: }
138: /*@
139: PetscSetFPTrap - Enables traps/exceptions on common floating point errors. This option may not work on certain systems or only a
140: subset of exceptions may be trapable.
142: Not Collective
144: Input Parameter:
145: . flag - values are
146: .vb
147: PETSC_FP_TRAP_OFF - do not trap any exceptions
148: PETSC_FP_TRAP_ON - all exceptions that are possible on the system except underflow
149: PETSC_FP_TRAP_INDIV - integer divide by zero
150: PETSC_FP_TRAP_FLTOPERR - improper argument to function, for example with real numbers, the square root of a negative number
151: PETSC_FP_TRAP_FLTOVF - overflow
152: PETSC_FP_TRAP_FLTUND - underflow - not trapped by default on most systems
153: PETSC_FP_TRAP_FLTDIV - floating point divide by zero
154: PETSC_FP_TRAP_FLTINEX - inexact floating point result
155: .ve
157: Options Database Key:
158: . -fp_trap <off,on> - turn on or off trapping of floating point exceptions
160: Level: advanced
162: Notes:
163: Preferred usage is `PetscFPTrapPush()` and `PetscFPTrapPop()` instead of this routine
165: Currently only `PETSC_FP_TRAP_OFF` and `PETSC_FP_TRAP_ON` are handled. All others are treated as `PETSC_FP_TRAP_ON`.
167: The values are bit values and may be |ed together in the function call
169: On systems that support it this routine causes floating point
170: overflow, divide-by-zero, and invalid-operand (e.g., a NaN), but not underflow, to
171: cause a message to be printed and the program to exit.
173: On many common systems, the floating
174: point exception state is not preserved from the location where the trap
175: occurred through to the signal handler. In this case, the signal handler
176: will just say that an unknown floating point exception occurred and which
177: function it occurred in. If you run with -fp_trap in a debugger, it will
178: break on the line where the error occurred. On systems that support C99
179: floating point exception handling You can check which
180: exception occurred using fetestexcept(FE_ALL_EXCEPT). See fenv.h
181: (usually at /usr/include/bits/fenv.h) for the enum values on your system.
183: .seealso: `PetscFPTrapPush()`, `PetscFPTrapPop()`, `PetscDetermineInitialFPTrap()`
184: @*/
185: PetscErrorCode PetscSetFPTrap(PetscFPTrap flag)
186: {
187: char *out;
189: PetscFunctionBegin;
190: /* Clear accumulated exceptions. Used to suppress meaningless messages from f77 programs */
191: (void)ieee_flags("clear", "exception", "all", &out);
192: if (flag == PETSC_FP_TRAP_ON) {
193: /*
194: To trap more fp exceptions, including underflow, change the line below to
195: if (ieee_handler("set","all",PetscDefaultFPTrap)) {
196: */
197: if (ieee_handler("set", "common", PetscDefaultFPTrap)) (*PetscErrorPrintf)("Can't set floatingpoint handler\n");
198: } else if (ieee_handler("clear", "common", PetscDefaultFPTrap)) (*PetscErrorPrintf)("Can't clear floatingpoint handler\n");
200: _trapmode = flag;
201: PetscCall(PetscInfo(NULL, "Using PETSC_HAVE_SUN4_STYLE_FPTRAP\n"));
202: PetscFunctionReturn(PETSC_SUCCESS);
203: }
205: /*@
206: PetscDetermineInitialFPTrap - Attempts to determine the floating point trapping that exists when `PetscInitialize()` is called
208: Not Collective
210: Note:
211: Currently only supported on Linux and macOS. Checks if divide by zero is enable and if so declares that trapping is on.
213: Level: advanced
215: .seealso: `PetscFPTrapPush()`, `PetscFPTrapPop()`, `PetscDetermineInitialFPTrap()`
216: @*/
217: PetscErrorCode PetscDetermineInitialFPTrap(void)
218: {
219: PetscFunctionBegin;
220: PetscCall(PetscInfo(NULL, "Unable to determine initial floating point trapping. Assuming it is off\n"));
221: PetscFunctionReturn(PETSC_SUCCESS);
222: }
224: /* -------------------------------------------------------------------------------------------*/
225: #elif defined(PETSC_HAVE_SOLARIS_STYLE_FPTRAP)
226: #include <sunmath.h>
227: #include <floatingpoint.h>
228: #include <siginfo.h>
229: #include <ucontext.h>
231: static struct {
232: int code_no;
233: char *name;
234: } error_codes[] = {
235: {FPE_FLTINV, "invalid floating point operand"},
236: {FPE_FLTRES, "inexact floating point result" },
237: {FPE_FLTDIV, "division-by-zero" },
238: {FPE_FLTUND, "floating point underflow" },
239: {FPE_FLTOVF, "floating point overflow" },
240: {0, "unknown error" }
241: };
242: #define SIGPC(scp) (scp->si_addr)
244: void PetscDefaultFPTrap(int sig, siginfo_t *scp, ucontext_t *uap)
245: {
246: int err_ind = -1, code = scp->si_code;
248: PetscFunctionBegin;
249: for (int j = 0; error_codes[j].code_no; j++) {
250: if (error_codes[j].code_no == code) err_ind = j;
251: }
253: if (err_ind >= 0) (void)(*PetscErrorPrintf)("*** %s occurred at pc=%X ***\n", error_codes[err_ind].name, SIGPC(scp));
254: else (*PetscErrorPrintf)("*** floating point error 0x%x occurred at pc=%X ***\n", code, SIGPC(scp));
256: PetscError(PETSC_COMM_SELF, 0, NULL, NULL, PETSC_ERR_FP, PETSC_ERROR_REPEAT, "floating point error");
257: PETSCABORT(MPI_COMM_WORLD, PETSC_ERR_FP);
258: }
260: PetscErrorCode PetscSetFPTrap(PetscFPTrap flag)
261: {
262: char *out;
264: PetscFunctionBegin;
265: /* Clear accumulated exceptions. Used to suppress meaningless messages from f77 programs */
266: (void)ieee_flags("clear", "exception", "all", &out);
267: if (flag == PETSC_FP_TRAP_ON) {
268: if (ieee_handler("set", "common", (sigfpe_handler_type)PetscDefaultFPTrap)) (*PetscErrorPrintf)("Can't set floating point handler\n");
269: } else {
270: if (ieee_handler("clear", "common", (sigfpe_handler_type)PetscDefaultFPTrap)) (*PetscErrorPrintf)("Can't clear floatingpoint handler\n");
271: }
272: _trapmode = flag;
273: PetscCall(PetscInfo(NULL,"Using PETSC_HAVE_SOLARIS_STYLE_FPTRAP\n");
274: PetscFunctionReturn(PETSC_SUCCESS);
275: }
277: PetscErrorCode PetscDetermineInitialFPTrap(void)
278: {
279: PetscFunctionBegin;
280: PetscCall(PetscInfo(NULL, "Unable to determine initial floating point trapping. Assuming it is off\n"));
281: PetscFunctionReturn(PETSC_SUCCESS);
282: }
284: /* ------------------------------------------------------------------------------------------*/
285: #elif defined(PETSC_HAVE_IRIX_STYLE_FPTRAP)
286: #include <sigfpe.h>
287: static struct {
288: int code_no;
289: char *name;
290: } error_codes[] = {
291: {_INVALID, "IEEE operand error" },
292: {_OVERFL, "floating point overflow" },
293: {_UNDERFL, "floating point underflow"},
294: {_DIVZERO, "floating point divide" },
295: {0, "unknown error" }
296: };
297: void PetscDefaultFPTrap(unsigned exception[], int val[])
298: {
299: int err_ind = -1, code = exception[0];
301: PetscFunctionBegin;
302: for (int j = 0; error_codes[j].code_no; j++) {
303: if (error_codes[j].code_no == code) err_ind = j;
304: }
305: if (err_ind >= 0) (void)(*PetscErrorPrintf)("*** %s occurred ***\n", error_codes[err_ind].name);
306: else (void)(*PetscErrorPrintf)("*** floating point error 0x%x occurred ***\n", code);
308: (void)PetscError(PETSC_COMM_SELF, 0, NULL, NULL, PETSC_ERR_FP, PETSC_ERROR_REPEAT, "floating point error");
309: PETSCABORT(MPI_COMM_WORLD, PETSC_ERR_FP);
310: }
312: PetscErrorCode PetscSetFPTrap(PetscFPTrap flag)
313: {
314: PetscFunctionBegin;
315: if (flag == PETSC_FP_TRAP_ON) handle_sigfpes(_ON, , _EN_UNDERFL | _EN_OVERFL | _EN_DIVZERO | _EN_INVALID, PetscDefaultFPTrap, _ABORT_ON_ERROR, 0);
316: else handle_sigfpes(_OFF, _EN_UNDERFL | _EN_OVERFL | _EN_DIVZERO | _EN_INVALID, 0, _ABORT_ON_ERROR, 0);
317: _trapmode = flag;
318: PetscCall(PetscInfo(NULL, "Using PETSC_HAVE_IRIX_STYLE_FPTRAP\n"));
319: PetscFunctionReturn(PETSC_SUCCESS);
320: }
322: PetscErrorCode PetscDetermineInitialFPTrap(void)
323: {
324: PetscFunctionBegin;
325: PetscCall(PetscInfo(NULL, "Unable to determine initial floating point trapping. Assuming it is off\n"));
326: PetscFunctionReturn(PETSC_SUCCESS);
327: }
329: /*----------------------------------------------- --------------------------------------------*/
330: #elif defined(PETSC_HAVE_RS6000_STYLE_FPTRAP)
331: /* In "fast" mode, floating point traps are imprecise and ignored.
332: This is the reason for the fptrap(FP_TRAP_SYNC) call */
333: struct sigcontext;
334: #include <fpxcp.h>
335: #include <fptrap.h>
336: #define FPE_FLTOPERR_TRAP (fptrap_t)(0x20000000)
337: #define FPE_FLTOVF_TRAP (fptrap_t)(0x10000000)
338: #define FPE_FLTUND_TRAP (fptrap_t)(0x08000000)
339: #define FPE_FLTDIV_TRAP (fptrap_t)(0x04000000)
340: #define FPE_FLTINEX_TRAP (fptrap_t)(0x02000000)
342: static struct {
343: int code_no;
344: char *name;
345: } error_codes[] = {
346: {FPE_FLTOPERR_TRAP, "IEEE operand error" },
347: {FPE_FLTOVF_TRAP, "floating point overflow" },
348: {FPE_FLTUND_TRAP, "floating point underflow" },
349: {FPE_FLTDIV_TRAP, "floating point divide" },
350: {FPE_FLTINEX_TRAP, "inexact floating point result"},
351: < {0, "unknown error" }
352: };
353: #define SIGPC(scp) (0) /* Info MIGHT be in scp->sc_jmpbuf.jmp_context.iar */
354: /*
355: For some reason, scp->sc_jmpbuf does not work on the RS6000, even though
356: it looks like it should from the include definitions. It is probably
357: some strange interaction with the "POSIX_SOURCE" that we require.
358: */
360: void PetscDefaultFPTrap(int sig, int code, struct sigcontext *scp)
361: {
362: int err_ind, j;
363: fp_ctx_t flt_context;
365: PetscFunctionBegin;
366: fp_sh_trap_info(scp, &flt_context);
368: err_ind = -1;
369: for (j = 0; error_codes[j].code_no; j++) {
370: if (error_codes[j].code_no == flt_context.trap) err_ind = j;
371: }
373: if (err_ind >= 0) (void)(*PetscErrorPrintf)("*** %s occurred ***\n", error_codes[err_ind].name);
374: else (void)(*PetscErrorPrintf)("*** floating point error 0x%x occurred ***\n", flt_context.trap);
376: (void)PetscError(PETSC_COMM_SELF, 0, NULL, NULL, PETSC_ERR_FP, PETSC_ERROR_REPEAT, "floating point error");
377: PETSCABORT(MPI_COMM_WORLD, PETSC_ERR_FP);
378: }
380: PetscErrorCode PetscSetFPTrap(PetscFPTrap flag)
381: {
382: PetscFunctionBegin;
383: if (flag == PETSC_FP_TRAP_ON) {
384: signal(SIGFPE, (void (*)(int))PetscDefaultFPTrap);
385: fp_trap(FP_TRAP_SYNC);
386: /* fp_enable(TRP_INVALID | TRP_DIV_BY_ZERO | TRP_OVERFLOW | TRP_UNDERFLOW); */
387: fp_enable(TRP_INVALID | TRP_DIV_BY_ZERO | TRP_OVERFLOW);
388: } else {
389: signal(SIGFPE, SIG_DFL);
390: fp_disable(TRP_INVALID | TRP_DIV_BY_ZERO | TRP_OVERFLOW | TRP_UNDERFLOW);
391: fp_trap(FP_TRAP_OFF);
392: }
393: _trapmode = flag;
394: PetscCall(PetscInfo(NULL, "Using PETSC_HAVE_RS6000_STYLE_FPTRAP\n"));
395: PetscFunctionReturn(PETSC_SUCCESS);
396: }
398: PetscErrorCode PetscDetermineInitialFPTrap(void)
399: {
400: PetscFunctionBegin;
401: PetscCall(PetscInfo(NULL, "Unable to determine initial floating point trapping. Assuming it is off\n"));
402: PetscFunctionReturn(PETSC_SUCCESS);
403: }
405: /* ------------------------------------------------------------*/
406: #elif defined(PETSC_HAVE_WINDOWS_COMPILERS)
407: #include <float.h>
408: void PetscDefaultFPTrap(int sig)
409: {
410: PetscFunctionBegin;
411: (void)(*PetscErrorPrintf)("*** floating point error occurred ***\n");
412: (void)PetscError(PETSC_COMM_SELF, 0, NULL, NULL, PETSC_ERR_FP, PETSC_ERROR_REPEAT, "floating point error");
413: PETSCABORT(MPI_COMM_WORLD, PETSC_ERR_FP);
414: }
416: PetscErrorCode PetscSetFPTrap(PetscFPTrap flag)
417: {
418: unsigned int cw;
420: PetscFunctionBegin;
421: if (flag == PETSC_FP_TRAP_ON) {
422: /* cw = _EM_INVALID | _EM_ZERODIVIDE | _EM_OVERFLOW | _EM_UNDERFLOW; */
423: cw = _EM_INVALID | _EM_ZERODIVIDE | _EM_OVERFLOW;
424: PetscCheck(SIG_ERR != signal(SIGFPE, PetscDefaultFPTrap), PETSC_COMM_SELF, PETSC_ERR_LIB, "Can't set floating point handler");
425: } else {
426: cw = 0;
427: PetscCheck(SIG_ERR != signal(SIGFPE, SIG_DFL), PETSC_COMM_SELF, PETSC_ERR_LIB, "Can't clear floating point handler");
428: }
429: (void)_controlfp(0, cw);
430: _trapmode = flag;
431: PetscCall(PetscInfo(NULL, "Using PETSC_HAVE_WINDOWS_COMPILERS FPTRAP\n"));
432: PetscFunctionReturn(PETSC_SUCCESS);
433: }
435: PetscErrorCode PetscDetermineInitialFPTrap(void)
436: {
437: PetscFunctionBegin;
438: PetscCall(PetscInfo(NULL, "Unable to determine initial floating point trapping. Assuming it is off\n"));
439: PetscFunctionReturn(PETSC_SUCCESS);
440: }
442: /* ------------------------------------------------------------*/
443: #elif defined(PETSC_HAVE_FENV_H) && !defined(__cplusplus)
444: /*
445: C99 style floating point environment.
447: Note that C99 merely specifies how to save, restore, and clear the floating
448: point environment as well as defining an enumeration of exception codes. In
449: particular, C99 does not specify how to make floating point exceptions raise
450: a signal. Glibc offers this capability through FE_NOMASK_ENV (or with finer
451: granularity, feenableexcept()), xmmintrin.h offers _MM_SET_EXCEPTION_MASK().
452: */
453: #include <fenv.h>
454: #if defined(PETSC_HAVE_FE_VALUES)
455: typedef struct {
456: int code;
457: const char *name;
458: } FPNode;
459: static const FPNode error_codes[] = {
460: {FE_DIVBYZERO, "divide by zero" },
461: {FE_INEXACT, "inexact floating point result" },
462: {FE_INVALID, "invalid floating point arguments (domain error)"},
463: {FE_OVERFLOW, "floating point overflow" },
464: {FE_UNDERFLOW, "floating point underflow" },
465: {0, "unknown error" }
466: };
467: #endif
469: void PetscDefaultFPTrap(int sig)
470: {
471: #if defined(PETSC_HAVE_FE_VALUES)
472: const FPNode *node;
473: int code;
474: PetscBool matched = PETSC_FALSE;
475: #endif
477: PetscFunctionBegin;
478: /* Note: While it is possible for the exception state to be preserved by the
479: * kernel, this seems to be rare which makes the following flag testing almost
480: * useless. But on a system where the flags can be preserved, it would provide
481: * more detail.
482: */
483: #if defined(PETSC_HAVE_FE_VALUES)
484: code = fetestexcept(FE_ALL_EXCEPT);
485: for (node = &error_codes[0]; node->code; node++) {
486: if (code & node->code) {
487: matched = PETSC_TRUE;
488: (void)(*PetscErrorPrintf)("*** floating point error \"%s\" occurred ***\n", node->name);
489: code &= ~node->code; /* Unset this flag since it has been processed */
490: }
491: }
492: if (!matched || code) { /* If any remaining flags are set, or we didn't process any flags */
493: (void)(*PetscErrorPrintf)("*** unknown floating point error occurred ***\n");
494: (void)(*PetscErrorPrintf)("The specific exception can be determined by running in a debugger. When the\n");
495: (void)(*PetscErrorPrintf)("debugger traps the signal, the exception can be found with fetestexcept(0x%x)\n", FE_ALL_EXCEPT);
496: (void)(*PetscErrorPrintf)("where the result is a bitwise OR of the following flags:\n");
497: (void)(*PetscErrorPrintf)("FE_INVALID=0x%x FE_DIVBYZERO=0x%x FE_OVERFLOW=0x%x FE_UNDERFLOW=0x%x FE_INEXACT=0x%x\n", FE_INVALID, FE_DIVBYZERO, FE_OVERFLOW, FE_UNDERFLOW, FE_INEXACT);
498: }
499: #else
500: (void)(*PetscErrorPrintf)("*** unknown floating point error occurred ***\n");
501: #endif
503: (void)(*PetscErrorPrintf)("Try option -start_in_debugger\n");
504: #if PetscDefined(USE_DEBUG)
505: #if !PetscDefined(HAVE_THREADSAFETY)
506: (void)(*PetscErrorPrintf)("likely location of problem given in stack below\n");
507: (void)(*PetscErrorPrintf)("--------------------- Stack Frames ------------------------------------\n");
508: (void)PetscStackView(PETSC_STDOUT);
509: #endif
510: #else
511: (void)(*PetscErrorPrintf)("configure using --with-debugging=yes, recompile, link, and run \n");
512: (void)(*PetscErrorPrintf)("with -start_in_debugger to get more information on the crash.\n");
513: #endif
514: (void)PetscError(PETSC_COMM_SELF, 0, NULL, NULL, PETSC_ERR_FP, PETSC_ERROR_INITIAL, "trapped floating point error");
515: PETSCABORT(MPI_COMM_WORLD, PETSC_ERR_FP);
516: }
518: PetscErrorCode PetscSetFPTrap(PetscFPTrap flag)
519: {
520: PetscFunctionBegin;
521: if (flag == PETSC_FP_TRAP_ON) {
522: /* Clear any flags that are currently set so that activating trapping will not immediately call the signal handler. */
523: PetscCheck(!feclearexcept(FE_ALL_EXCEPT), PETSC_COMM_SELF, PETSC_ERR_LIB, "Cannot clear floating point exception flags");
524: #if defined(FE_NOMASK_ENV) && defined(PETSC_HAVE_FE_VALUES)
525: /* Could use fesetenv(FE_NOMASK_ENV), but that causes spurious exceptions (like gettimeofday() -> PetscLogDouble). */
526: /* PetscCheck(feenableexcept(FE_DIVBYZERO | FE_INVALID | FE_OVERFLOW | FE_UNDERFLOW) != -1,PETSC_COMM_SELF,PETSC_ERR_LIB,"Cannot activate floating point exceptions"); */
527: /* Doesn't work on AArch64 targets. There's a known hardware limitation. Need to detect hardware at configure time? */
528: PetscCheck(feenableexcept(FE_DIVBYZERO | FE_INVALID | FE_OVERFLOW) != -1, PETSC_COMM_SELF, PETSC_ERR_LIB, "Cannot activate floating point exceptions");
529: PetscCall(PetscInfo(NULL, "Using PETSC_HAVE_FENV_H FPTRAP with FE_NOMASK_ENV\n"));
530: #elif defined PETSC_HAVE_XMMINTRIN_H
531: _MM_SET_EXCEPTION_MASK(_MM_GET_EXCEPTION_MASK() & ~_MM_MASK_DIV_ZERO);
532: /* _MM_SET_EXCEPTION_MASK(_MM_GET_EXCEPTION_MASK() & ~_MM_MASK_UNDERFLOW); */
533: _MM_SET_EXCEPTION_MASK(_MM_GET_EXCEPTION_MASK() & ~_MM_MASK_OVERFLOW);
534: _MM_SET_EXCEPTION_MASK(_MM_GET_EXCEPTION_MASK() & ~_MM_MASK_INVALID);
535: PetscCall(PetscInfo(NULL, "Using PETSC_HAVE_FENV_H FPTRAP with PETSC_HAVE_XMMINTRIN_H\n"));
536: #else
537: /* C99 does not provide a way to modify the environment so there is no portable way to activate trapping. */
538: PetscCall(PetscInfo(NULL, "Using PETSC_HAVE_FENV_H FPTRAP\n"));
539: #endif
540: PetscCheck(SIG_ERR != signal(SIGFPE, PetscDefaultFPTrap), PETSC_COMM_SELF, PETSC_ERR_LIB, "Can't set floating point handler");
541: } else {
542: PetscCheck(!fesetenv(FE_DFL_ENV), PETSC_COMM_SELF, PETSC_ERR_LIB, "Cannot disable floating point exceptions");
543: /* can use _MM_SET_EXCEPTION_MASK(_MM_GET_EXCEPTION_MASK() | _MM_MASK_UNDERFLOW); if PETSC_HAVE_XMMINTRIN_H exists */
544: PetscCheck(SIG_ERR != signal(SIGFPE, SIG_DFL), PETSC_COMM_SELF, PETSC_ERR_LIB, "Can't clear floating point handler");
545: }
546: _trapmode = flag;
547: PetscFunctionReturn(PETSC_SUCCESS);
548: }
550: PetscErrorCode PetscDetermineInitialFPTrap(void)
551: {
552: #if defined(FE_NOMASK_ENV) || defined PETSC_HAVE_XMMINTRIN_H
553: unsigned int flags;
554: #endif
556: PetscFunctionBegin;
557: #if defined(FE_NOMASK_ENV)
558: flags = fegetexcept();
559: if (flags & FE_DIVBYZERO) {
560: #elif defined PETSC_HAVE_XMMINTRIN_H
561: flags = _MM_GET_EXCEPTION_MASK();
562: if (!(flags & _MM_MASK_DIV_ZERO)) {
563: #else
564: PetscCall(PetscInfo(NULL, "Floating point trapping unknown, assuming off\n"));
565: PetscFunctionReturn(PETSC_SUCCESS);
566: #endif
567: #if defined(FE_NOMASK_ENV) || defined PETSC_HAVE_XMMINTRIN_H
568: _trapmode = PETSC_FP_TRAP_ON;
569: PetscCall(PetscInfo(NULL, "Floating point trapping is on by default %d\n", flags));
570: } else {
571: _trapmode = PETSC_FP_TRAP_OFF;
572: PetscCall(PetscInfo(NULL, "Floating point trapping is off by default %d\n", flags));
573: }
574: PetscFunctionReturn(PETSC_SUCCESS);
575: #endif
576: }
578: /* ------------------------------------------------------------*/
579: #elif defined(PETSC_HAVE_IEEEFP_H)
580: #include <ieeefp.h>
581: void PetscDefaultFPTrap(int sig)
582: {
583: PetscFunctionBegin;
584: (void)(*PetscErrorPrintf)("*** floating point error occurred ***\n");
585: (void)PetscError(PETSC_COMM_SELF, 0, NULL, NULL, PETSC_ERR_FP, PETSC_ERROR_REPEAT, "floating point error");
586: PETSCABORT(MPI_COMM_WORLD, PETSC_ERR_FP);
587: }
589: PetscErrorCode PetscSetFPTrap(PetscFPTrap flag)
590: {
591: PetscFunctionBegin;
592: if (flag == PETSC_FP_TRAP_ON) {
593: #if defined(PETSC_HAVE_FPRESETSTICKY)
594: fpresetsticky(fpgetsticky());
595: #elif defined(PETSC_HAVE_FPSETSTICKY)
596: fpsetsticky(fpgetsticky());
597: #endif
598: fpsetmask(FP_X_INV | FP_X_DZ | FP_X_OFL | FP_X_OFL);
599: PetscCheck(SIG_ERR != signal(SIGFPE, PetscDefaultFPTrap), PETSC_COMM_SELF, PETSC_ERR_LIB, "Can't set floating point handler");
600: } else {
601: #if defined(PETSC_HAVE_FPRESETSTICKY)
602: fpresetsticky(fpgetsticky());
603: #elif defined(PETSC_HAVE_FPSETSTICKY)
604: fpsetsticky(fpgetsticky());
605: #endif
606: fpsetmask(0);
607: PetscCheck(SIG_ERR != signal(SIGFPE, SIG_DFL), PETSC_COMM_SELF, PETSC_ERR_LIB, "Can't clear floating point handler");
608: }
609: _trapmode = flag;
610: PetscCall(PetscInfo(NULL, "Using PETSC_HAVE_IEEEFP_H FPTRAP\n"));
611: PetscFunctionReturn(PETSC_SUCCESS);
612: }
614: PetscErrorCode PetscDetermineInitialFPTrap(void)
615: {
616: PetscFunctionBegin;
617: PetscCall(PetscInfo(NULL, "Unable to determine initial floating point trapping. Assuming it is off\n"));
618: PetscFunctionReturn(PETSC_SUCCESS);
619: }
621: /* -------------------------Default -----------------------------------*/
622: #else
624: static void PetscDefaultFPTrap(int sig)
625: {
626: PetscFunctionBegin;
627: (void)(*PetscErrorPrintf)("*** floating point error occurred ***\n");
628: (void)PetscError(PETSC_COMM_SELF, 0, NULL, NULL, PETSC_ERR_FP, PETSC_ERROR_REPEAT, "floating point error");
629: PETSCABORT(MPI_COMM_WORLD, PETSC_ERR_FP);
630: }
632: PetscErrorCode PetscSetFPTrap(PetscFPTrap flag)
633: {
634: PetscFunctionBegin;
635: if (flag == PETSC_FP_TRAP_ON) {
636: if (SIG_ERR == signal(SIGFPE, PetscDefaultFPTrap)) PetscCall((*PetscErrorPrintf)("Can't set floatingpoint handler\n"));
637: } else if (SIG_ERR == signal(SIGFPE, SIG_DFL)) PetscCall((*PetscErrorPrintf)("Can't clear floatingpoint handler\n"));
639: _trapmode = flag;
640: PetscCall(PetscInfo(NULL, "Using default FPTRAP\n"));
641: PetscFunctionReturn(PETSC_SUCCESS);
642: }
644: PetscErrorCode PetscDetermineInitialFPTrap(void)
645: {
646: PetscFunctionBegin;
647: PetscCall(PetscInfo(NULL, "Unable to determine initial floating point trapping. Assuming it is off\n"));
648: PetscFunctionReturn(PETSC_SUCCESS);
649: }
650: #endif