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character*8 out i = ieee_flags ('get', 'exception', 'division', out)

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i = ieee_flags("get", "exception", "all", out);

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¥¢¥ó¥À¡¼¥Õ¥í¡¼	fp_underflow	i & (1 << fp_underflow)
ÉÔÀµ³Î	fp_inexact	i & (1 << fp_inexact)
ÈóÀµµ¬¿ô	fp_denormalized	i & (1 << fp_denormalized) (x86 ¤Î¤ß)

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/* * ¤¹¤Ù¤Æ¤ÎÎßÀÑÎã³°¤ò¼¨¤¹À°¿ôÃͤò¥Ç¥³¡¼¥É¤·¤Þ¤¹¡£ * fp_inexact ¤Ê¤É¤Ï¡¢<sys/ieeefp.h> Æâ¤ËÄêµÁ¤µ¤ì¤Æ¤¤¤Þ¤¹¡£ */ char *out; int invalid, division, overflow, underflow, inexact; code = ieee_flags("get", "exception", "", &out); printf ("out is %s, code is %d, in hex: 0x%08X\n", out, code, code); inexact = (code >> fp_inexact) & 0x1; division = (code >> fp_division) & 0x1; underflow = (code >> fp_underflow) & 0x1; overflow = (code >> fp_overflow) & 0x1; invalid = (code >> fp_invalid) & 0x1; printf("%d %d %d %d %d \n", invalid, division, overflow, underflow, inexact);

C99 Îã³°¥Õ¥é¥°´Ø¿ô

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feclearexcept(FE_ALL_EXCEPT);

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int i; i = fetestexcept(FE_IMVALID | FE_DIVBYZERO); if (i& FE_INVALID) /* ̵¸ú¤ÊÎã³°¤¬È¯À¸¤·¤Þ¤·¤¿ */ else if (i & FE_DIVBYZERO) /* ¥¼¥í½ü»»Îã³°¤¬È¯À¸¤·¤Þ¤·¤¿ */

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feraiseexcept(FE_OVERFLOW);

fegetexceptflag ¤ª¤è¤Ó fesetexceptflag ´Ø¿ô¤Ï¡¢¥Õ¥é¥°¤Î¥µ¥Ö¥»¥Ã¥È¤ÎÊݸ¤ÈÉü¸µ¤Ë»ÈÍѤ·¤Þ¤¹¡£¼¡¤Ë¡¢¤³¤Î 2 ¤Ä¤Î´Ø¿ô¤ò»ÈÍѤ·¤¿Îã¤ò¼¨¤·¤Þ¤¹¡£

fexcept_t flags; /* ¥¢¥ó¥À¡¼¥Õ¥í¡¼¡¢¥ª¡¼¥Ð¡¼¥Õ¥í¡¼¡¢¤ª¤è¤ÓÉÔÀµ³Î¤Î¥Õ¥é¥°¤òÊݸ¤·¤Þ¤¹ */ fegetexceptflag(&flags, FE_UNDERFLOW | FE_OVERFLOW | FE_INEXACT); /* ¤³¤ì¤é¤Î¥Õ¥é¥°¤ò¥¯¥ê¥¢¤·¤Þ¤¹ */ feclearexcept(FE_UNDERFLOW | FE_OVERFLOW | FE_INEXACT); /* ¥¢¥ó¥À¡¼¥Õ¥í¡¼¤Þ¤¿¤Ï¥ª¡¼¥Ð¡¼¥Õ¥í¡¼¤Î²ÄǽÀ­¤Î¤¢¤ë±é»»¤ò¹Ô¤¤¤Þ¤¹ */ ... /* ¥¢¥ó¥À¡¼¥Õ¥í¡¼¤Þ¤¿¤Ï¥ª¡¼¥Ð¡¼¥Õ¥í¡¼¤òÄ´¤Ù¤Þ¤¹ */ if (fetestexcept(FE_UNDERFLOW | FE_OVERFLOW) != 0) { ... } /* ¥¢¥ó¥À¡¼¥Õ¥í¡¼¡¢¥ª¡¼¥Ð¡¼¥Õ¥í¡¼¡¢¤ª¤è¤ÓÉÔÀµ³Î¤Î¥Õ¥é¥°¤òÉü¸µ¤·¤Þ¤¹ */ fesetexceptflag(&flags, FE_UNDERFLOW | FE_OVERFLOW, | FE_INEXACT);

Îã³°¤ÎÆÃÄê

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program ex double precision x,y sqrtm1 x = -4.2d0 y = sqrtm1(x) print * , x, y end double precision function sqrtm1(x) double precision x routine = sqrt(x) - 1.0d0 return end

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-4.2000000000000 NaN Note: IEEE floating-point exception flags raised: Inexact; Invalid Operation; See the Numerical Computation Guide, ieee_flags(3M) [ÆüËܸìÌõ] Ãí: °Ê²¼¤Î IEEE ÉâÆ°¾®¿ôÅÀÎã³°¤¬È¯À¸¤·¤Þ¤·¤¿: ÉÔÀµ³Î¡¢Ìµ¸ú¤Ê±é»» ¾ÜºÙ¤Ï¡¢¡Ø¿ôÃÍ·×»»¥¬¥¤¥É¡Ù¤Î ieee_flags(3M) ¤Ë´Ø¤¹¤ëÀâÌÀ¤ò»²¾È¤·¤Æ¤¯¤À¤µ ¤¤¡£

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example% f77 -g -ftrap=invalid ex.f

-g ¥ª¥×¥·¥ç¥ó¤Ç¥³¥ó¥Ñ¥¤¥ë¤¹¤ë¤È¡¢ dbx ¤Î¥½¡¼¥¹¥ì¥Ù¥ë¤Î¥Ç¥Ð¥Ã¥°µ¡Ç½¤ò»ÈÍѤ¹¤ë¤³¤È¤¬¤Ç¤­¤Þ¤¹¡£-ftrap=invalid ¤ò»ØÄꤹ¤ë¤È¡¢Ìµ¸ú¤Ê±é»»¤ËÂФ¹¤ëÎã³°¤Î¥È¥é¥Ã¥×¤òÍ­¸ú¤Ë¤·¤Æ¥×¥í¥°¥é¥à¤¬¼Â¹Ô¤µ¤ì¤Þ¤¹¡£

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catch fpe ¥³¥Þ¥ó¥É¤ò¼Â¹Ô¤·¡¢¥×¥í¥°¥é¥à¤ò¼Â¹Ô¤·¤Þ¤¹¡£·ë²Ì¤Ï¼¡¤Î¤è¤¦¤Ë¤Ê¤ê¤Þ¤¹¡£

example% dbx a.out Reading symbolic information for a.out Reading symbolic information for rtld /usr/lib/ld.so.1 Reading symbolic information for libF77.so.3 Reading symbolic information for libsunmath.so.1 Reading symbolic information for libm.so.1 Reading symbolic information for libc.so.1 Reading symbolic information for libdl.so.1 (dbx) catch fpe (dbx) run Running: a.out (process id 17516) signal FPE (invalid floating point operation) in sqrtm1 at line 10 in file "ex.f" 10 sqrtm1 = sqrt(x) - 1.0d0 (dbx) print x x = -4.2 (dbx)

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adb ¤ò»ÈÍѤ·¤ÆÎã³°¤Î¸¶°ø¤È¤Ê¤Ã¤Æ¤¤¤ëÌ¿Îá¤òÆÃÄꤹ¤ë

adb ¤ò»ÈÍѤ·¤ÆÎã³°¤Î¸¶°ø¤òÆÃÄꤹ¤ë¤³¤È¤â¤Ç¤­¤Þ¤¹¡£¤¿¤À¤·¡¢dbx ¤È¤Ï°Û¤Ê¤ê¡¢adb ¤Ç¤Ï¥½¡¼¥¹¥Õ¥¡¥¤¥ë¤ä¹ÔÈÖ¹æ¤ÏÆÃÄê¤Ç¤­¤Þ¤»¤ó¡£adb ¤ò»ÈÍѤ¹¤ë¾ì¹ç¤â¡¢ºÇ½é¤Î¼ê½ç¤Ï
-ftrap ¤ò»ØÄꤷ¤Æ¥×¥í¥°¥é¥à¤òºÆ¥³¥ó¥Ñ¥¤¥ë¤·¤Þ¤¹¡£

example% f77 -ftrap=invalid ex.f

¼¡¤Ë adb ¤òµ¯Æ°¤·¤Æ¥×¥í¥°¥é¥à¤ò¼Â¹Ô¤·¤Þ¤¹¡£Ìµ¸ú¤Ê±é»»Îã³°¤¬È¯À¸¤¹¤ë¤È¡¢adb ¤ÏÎã³°¤Î¸¶°ø¤Ç¤¢¤ëÌ¿Îá¤Î¼¡¤ÎÌ¿Îá¤ÇÄä»ß¤·¤Þ¤¹¡£Îã³°¤Î¸¶°ø¤Ç¤¢¤ëÌ¿Îá¤ò¸«¤Ä¤±¤ë¤Ë¤Ï¡¢¤¤¤¯¤Ä¤«¤ÎÌ¿Îá¤òµÕ¥¢¥»¥ó¥Ö¥ë¤·¡¢adb ¤¬Ää»ß¤·¤¿Ì¿Îá¤è¤êÁ°¤Ë¤¢¤ëºÇ¸å¤ÎÉâÆ°¾®¿ôÅÀÌ¿Îá¤òõ¤·¤Þ¤¹¡£SPARC ¥¢¡¼¥­¥Æ¥¯¥Á¥ã¤Î¥·¥¹¥Æ¥à¤Ç¤Ï¡¢·ë²Ì¤Ï¼¡¤ÎÎã¤Î¤è¤¦¤Ë¤Ê¤ê¤Þ¤¹¡£

example% adb a.out :r SIGFPE 8: numerical exception (invalid floating point operation) stopped at routine_+0x20: ldd [%l0], %f2 routine_+10?5i routine_+0x10: ld [%l0 + 0x4], %f3 fsqrtd %f2, %f4 sethi %hi(0x11c00), %l0 or %l0, 0x1d8, %l0 ldd [%l0], %f2 <f2=F -4.2000000000000002e+00

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example% adb a.out :r SIGFPE: Arithmetic Exception (invalid floating point operation) stopped at sqrtm1_+0x13: faddp %st,%st(1) sqrtm1_?8i sqrtm1_: sqrtm1_: pushl %ebp movl %esp,%ebp subl $0x24,%esp fldl $0x8048b88 movl 0x8(%ebp),%eax fldl (%eax) fsqrt faddp %st,%st(1) $x 80387 chip is present. cw 0x137e sw 0x3000 cssel 0x17 ipoff 0x8acd datasel 0x1f dataoff 0x0 st[0] -4.2000000000000001776356839 VALID st[1] -1.0 VALID st[2] +0.0 EMPTY st[3] +0.0 EMPTY st[4] +0.0 EMPTY st[5] +0.0 EMPTY st[6] +0.0 EMPTY st[7] +0.0 EMPTY

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example% dbx a.out Reading symbolic information for a.out Reading symbolic information for rtld /usr/lib/ld.so.1 Reading symbolic information for libF77.so.3 Reading symbolic information for libsunmath.so.1 Reading symbolic information for libm.so.1 Reading symbolic information for libc.so.1 Reading symbolic information for libdl.so.1 (dbx) stop in sqrtm1_ dbx: warning: 'sqrtm1_' has no debugger info -- will trigger on first instruction (2) stop in sqrtm1_ (dbx) run Running: a.out (process id 6631) stopped in sqrtm1_ at 0x10c00 0x00010c00: sqrtm1_ : save %sp, -0x68, %sp (dbx) assign $fsr=0x08000000 dbx: warning: unknown language, 'fortran' assumed (dbx) catch fpe (dbx) cont signal FPE (invalid floating point operation) in sqrtm1_ at 0x10c20 0x00010c20: sqrtm1_+0x0020: ldd [%l0], %f2 (dbx)

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example% dbx a.out Reading symbolic information for a.out Reading symbolic information for rtld /usr/lib/ld.so.1 Reading symbolic information for libF77.so.3 Reading symbolic information for libsunmath.so.1 Reading symbolic information for libm.so.1 Reading symbolic information for libc.so.1 Reading symbolic information for libdl.so.1 (dbx) stop in main dbx: warning: 'main' has no debugger info -- will trigger on first instruction (2) stop in main (dbx) run Running: a.out (process id 3285) stopped in main at 0x8048b00 0x00010c00: main : push1 %ebp (dbx) assign $fctrl=0x137e (dbx) catch fpe (dbx) cont signal FPE (invalid floating point operation) in main at 0x8048add 0x08048add: sqrtm1_+0x000d: fadd 0x8048bac (dbx)

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#include <ieeefp.h> #pragma init (trapinvalid) void trapinvalid() { /* FP_X_INV ¤Ê¤É¤Ï ieeefp.h Æâ¤ÇÄêµÁ¤µ¤ì¤Æ¤¤¤Þ¤¹*/ fpsetmask(FP_X_INV); }

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example% cc -c init.c example% f77 ex.o init.o example% a.out Floating point exception 7, invalid operand, occurred at address 8048afd. Abort

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example% cc -Kpic -G -ztext init.c -o init.so -lc

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example% env LD_PRELOAD=./init.so a.out Floating point exception 7, invalid operand, occurred at address 10c24. Abort

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#include <ieeefp.h> #include <sunmath.h> #include <sys/sysi86.h> #pragma init (trapinvalid) void trapinvalid() { /* FP_X_INV et al ¤Ï ieeefp.h ¤ÇÄêµÁ¤µ¤ì¤Þ¤¹ */ fpsetmask(FP_X_INV); } extern int __fltrounds(), __flt_rounds; extern long _fp_hw; void __fpstart() { char *out; /* System V ABI Intel ¥×¥í¥»¥Ã¥µ¥µ¥×¥ê¥á¥ó¥È¤Ë¤è¤Ã¤ÆÄêµÁ¤µ¤ì¤Æ¤¤¤ë ɸ½à¤Î __fpstart() ´Ø¿ô¤ÈƱ¤¸ÉâÆ°¾®¿ôÅÀ½é´ü²½¤ò¼Â¹Ô¤·¤Þ¤¹¤¬¡¢ ¤¹¤Ù¤Æ¤Î¥È¥é¥Ã¥×¥â¡¼¥É¤ò¤½¤Î¤Þ¤Þ¤Ë¤·¤Þ¤¹ */ __flt_rounds = __fltrounds(); sysi86(SI86FPHW, &_fp_hw); _fp_hw &= 0xff; ieee_flags("set", "precision", "extended", &out); }

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example% cc -Kpic -G -ztext init.c -o init.so -lc example% env LD_PRELOAD=./init.so a.out Floating point exception 7, invalid operand, occurred at address 8048afd. Abort

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action	char *	get¡¢set¡¢clear
exception	char *	invalid¡¢division¡¢overflow¡¢underflow¡¢inexact¡¢ all¡¢common
handler	sigfpe_handler_type	¥æ¡¼¥¶¡¼ÄêµÁ¥ë¡¼¥Á¥ó SIGFPE_DEFAULT SIGFPE_IGNORE SIGFPE_ABORT

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#include <sunmath.h> if (ieee_handler("clear", "all", 0) != 0) printf("could not clear exception handlers\n");

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i = ieee_handler('clear', 'all', 0) if (i.ne.0) print *, 'could not clear exception handlers'

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SIGFPE ·¿Ì¾	IEEE ·¿
FPE_INTDIV
FPE_INTOVF
FPE_FLTRES	ÉÔÀµ³Î
FPE_FLTDIV	½ü»»
FPE_FLTUND	¥¢¥ó¥À¡¼¥Õ¥í¡¼
FPE_FLTINV	̵¸ú
FPE_FLTOVF	¥ª¡¼¥Ð¡¼¥Õ¥í¡¼

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#include <stdio.h> #include <sys/ieeefp.h> #include <sunmath.h> #include <siginfo.h> #include <ucontext.h> void handler(int sig, siginfo_t *sip, ucontext_t *uap) { unsigned code, addr; #ifdef i386 unsigned sw; sw = uap->uc_mcontext.fpregs.fp_reg_set.fpchip_state.status & ~uap->uc_mcontext.fpregs.fp_reg_set.fpship_state.state[0]; if (sw & (1 << fp_invalid)) code = FPE_FLTINV; else if (sw & (1 << fp_division)) code = FPE_FLTDIV; else if (sw & (1 << fp_overflow)) code = FPE_FLTOVF; else if (sw & (1 << fp_underflow)) code = FPE_FLTUND; else if (sw & (1 << fp_inexact)) code = FPE_FLTRES; else code = 0; addr = uap->uc_mcontext.fpregs.fp_reg_set.fpchip_state. state[3]; #else code = sip->si_code; addr = (unsigned) sip->si_addr; #endif fprintf(stderr, "fp exception %x at address %x\n", code, addr); } int main() { double x; /* ¶¦Ä̤ÎÉâÆ°¾®¿ôÅÀÎã³°¤ò¥È¥é¥Ã¥×¤·¤Þ¤¹ */ if (ieee_handler("set", "common", handler) != 0) printf("Did not set exception handler\n"); /* ¥¢¥ó¥À¡¼¥Õ¥í¡¼Îã³°¤òȯÀ¸¤µ¤»¤Þ¤¹(Êó¹ð¤µ¤ì¤Þ¤»¤ó) */ x = min_normal(); printf("min_normal = %g\n", x); x = x / 13.0; printf("min_normal / 13.0 = %g\n", x); /* ¥ª¡¼¥Ð¡¼¥Õ¥í¡¼Îã³°¤òȯÀ¸¤µ¤»¤Þ¤¹(Êó¹ð¤µ¤ì¤Þ¤¹) */ x = max_normal(); printf("max_normal = %g\n", x); x = x * x; printf("max_normal * max_normal = %g\n", x); ieee_retrospective(stderr); return 0; }

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min_normal = 2.22507e-308 min_normal / 13.0 = 1.7116e-309 max_normal = 1.79769e+308 fp exception 4 at address 10d0c max_normal * max_normal = 1.79769e+308 Note: IEEE floating-point exception flags raised: Inexact; Underflow; IEEE floating-point exception traps enabled: overflow; division by zero; invalid operation; See the Numerical Computation Guide, ieee_flags(3M), ieee_handler(3M) [ÆüËܸìÌõ] Ãí: °Ê²¼¤Î IEEE ÉâÆ°¾®¿ôÅÀÎã³°¤¬È¯À¸¤·¤Þ¤·¤¿: ÉÔÀµ³Î¡¢¥¢¥ó¥À¡¼¥Õ¥í¡¼ °Ê²¼¤Î IEEE ÉâÆ°¾®¿ôÅÀÎã³°¤Î¥È¥é¥Ã¥×¤¬Í­¸ú¤Ç¤¹: ¥ª¡¼¥Ð¡¼¥Õ¥í¡¼¡¢¥¼¥í¤Ë¤è¤ë½ü»»¡¢Ìµ¸ú¤Ê±é»» ¾ÜºÙ¤Ï¡¢¡Ø¿ôÃÍ·×»»¥¬¥¤¥É¡Ù¤Î ieee_flags(3M), ieee_handler(3M) ¤Ë´Ø¤¹¤ëÀâÌÀ¤ò»²¾È¤·¤Æ¤¯¤À¤µ¤¤¡£

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ret = fex_set_handling (ex, mode, handler);

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fex_set_handling(FEX_INV_ZDZ, FEX_ABORT, NULL);

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fex_set_handling(FEX_OVERFLOW | FEX_DIVBYZERO, FEX_SIGNAL, handler);

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#include <fenv.h> void handler(int ex, fex_info_t *info) { switch (ex) { case FEX_OVERFLOW: printf("Overflow in "); break; case FEX_DIVBYZERO: printf("Division by zero in "); break; default: printf("Invalid operation in "); } switch (info->op) { case fex_add: printf("floating point add\n"); break; case fex_sub: printf("floating point subtract\n"); break; case fex_mul: printf("floating point multiply\n"); break; case fex_div: printf("floating point divide\n"); break; case fex_sqrt: printf("floating point square root\n"); break; case fex_cnvt: printf("floating point conversion\n"); break; case fex_cmp: printf("floating point compare\n"); break; default: printf("unknown operation\n"); } switch (info->op1.type) { case fex_int: printf("operand 1: %d\n", info->op1.val.i); break; case fex_llong: printf("operand 1: %lld\n", info->op1.val.l); break; case fex_float: printf("operand 1: %g\n", info->op1.val.f); break; case fex_double: printf("operand 1: %g\n", info->op1.val.d); break; case fex_ldouble: printf("operand 1: %Lg\n", info->op1.val.q); break; } switch (info->op2.type) { case fex_int: printf("operand 2: %d\n", info->op2.val.i); break; case fex_llong: printf("operand 2: %lld\n", info->op2.val.l); break; case fex_float: printf("operand 2: %g\n", info->op2.val.f); break; case fex_double: printf("operand 2: %g\n", info->op2.val.d); break; case fex_ldouble: printf("operand 2: %Lg\n", info->op2.val.q); break; } } ... fex_set_handling(FEX_COMMON, FEX_CUSTOM, handler);

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#include <stdio.h> #include <stdlib.h> #include <string.h> #include <fenv.h> static struct ftrap_string { const char *name; int value; } ftrap_table[] = { { "inexact", FEX_INEXACT }, { "division", FEX_DIVBYZERO }, { "underflow", FEX_UNDERFLOW }, { "overflow", FEX_OVERFLOW }, { "invalid", FEX_INVALID }, { NULL, 0 } }; #pragma init (set_ftrap) void set_ftrap() { struct ftrap_string *f; char *s, *s0; int ex = 0; if ((s = getenv("FTRAP")) == NULL) return; if ((s0 = strtok(s, ",")) == NULL) return; do { for (f = &trap_table[0]; f->name != NULL; f++) { if (!strcmp(s0, f->name)) ex |= f->value; } } while ((s0 = strtok(NULL, ",")) != NULL); fex_set_handling(ex, FEX_ABORT, NULL); fex_set_log(stderr); }

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example% cc -Kpic -G -ztext init.c -o init.so -R/opt/SUNWspro/lib -L/opt/SUNWspro/lib -lm9x -lc example% env FTRAP=invalid LD_PRELOAD=./init.so a.out Floating point invalid operation (sqrt) at 0x00010c24 sqrtm1_, abort 0x00010c30 sqrtm1_ 0x00010b48 MAIN_ 0x00010ccc main Abort

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#include <stdio.h>

#include <ieeefp.h>

#include <math.h>

#include <sunmath.h>

#include <siginfo.h>

#include <ucontext.h>

#ifdef V8PLUS /* ¾å°Ì 32 ¥Ó¥Ã¥È¤ÎÉâÆ°¾®¿ôÅÀ¥ì¥¸¥¹¥¿¤Ï¡¢uap->uc_mcontext.xrs.xrs_prt ¤Ë¤è¤Ã¤Æ¼¨¤µ¤ì¤ëÎΰè¤Ë³ÊǼ¤µ¤ì¤Þ¤¹¡£¤³¤Î¥Ý¥¤¥ó¥¿¤Ï¡¢ uap->mcontext.xrs.xrs_id == XRS_ID (sys/procfs.h ¤ÇÄêµÁ¤µ¤ì¤Æ¤¤¤ë) ¤Î¾ì¹ç¤Î¤ßÍ­¸ú¤Ç¤¹¡£ */

#include <assert.h>

#include <sys/procfs.h>

#define FPxreg(x) ((prxregset_t*)uap->uc_mcontext.xrs.xrs_ptr)

->pr_un.pr_v8p.pr_xfr.pr_regs[(x)]

#endif

#define FPreg(x) uap->uc_mcontext.fpregs.fpu_fr.fpu_regs[(x)]

/*

* ¥È¥é¥Ã¥×¤µ¤ì¤¿¥¢¥ó¥À¡¼¥Õ¥í¡¼¤Þ¤¿¤Ï¥ª¡¼¥Ð¡¼¥Õ¥í¡¼¤Ë¤Ä¤¤¤Æ¡¢ * IEEE 754 ¤Î¥Ç¥Õ¥©¥ë¥È¤Î·ë²Ì¤¬Ä󶡤µ¤ì¤Þ¤¹

*/

void

ieee_trapped_default(int sig, siginfo_t *sip, ucontext_t *uap)

{

unsigned instr, opf, rs1, rs2, rd;

long double qs1, qs2, qd, qscl;

double ds1, ds2, dd, dscl;

float fs1, fs2, fd, fscl;

/* Îã³°¤Î¸¶°ø¤È¤Ê¤Ã¤Æ¤¤¤ëÌ¿Îá¤ò¼èÆÀ */

instr = uap->uc_mcontext.fpregs.fpu_q->FQu.fpq.fpq_instr;

/* ±é»»¥³¡¼¥É¡¢¥½¡¼¥¹¡¢°¸Àè¥ì¥¸¥¹¥¿ÈÖ¹æ¤òÃê½Ð */

opf = (instr >> 5) & 0x1ff;

rs1 = (instr >> 14) & 0x1f;

rs2 = instr & 0x1f;

rd = (instr >> 25) & 0x1f;

/* ¥ª¥Ú¥é¥ó¥É¤ò¼èÆÀ */

switch (opf & 3) {

case 1: /* single precision */

fs1 = *(float*)&FPreg(rs1);

fs2 = *(float*)&FPreg(rs2);

break;

case 2: /* ÇÜÀºÅÙ */

#ifdef V8PLUS

if (rs1 & 1)

{

assert(uap->uc_mcontext.xrs.xrs_id == XRS_ID);

ds1 = *(double*)&FPxreg(rs1 & 0x1e);

}

else

ds1 = *(double*)&FPreg(rs1);

if (rs2 & 1)

{

assert(uap->uc_mcontext.xrs.xrs_id == XRS_ID);

ds2 = *(double*)&FPxreg(rs2 & 0x1e);

}

else

ds2 = *(double*)&FPreg(rs2);

#else

ds1 = *(double*)&FPreg(rs1);

ds2 = *(double*)&FPreg(rs2);

#endif

break;

case 3: /* 4 ÇÜÀºÅÙ */

#ifdef V8PLUS

if (rs1 & 1)

{

assert(uap->uc_mcontext.xrs.xrs_id == XRS_ID);

qs1 = *(long double*)&FPxreg(rs1 & 0x1e);

}

else

qs1 = *(long double*)&FPreg(rs1);

if (rs2 & 1)

{

assert(uap->uc_mcontext.xrs.xrs_id == XRS_ID);

qs2 = *(long double*)&FPxreg(rs2 & 0x1e);

}

else

qs2 = *(long double*)&FPreg(rs2);

#else

qs1 = *(long double*)&FPreg(rs1);

qs2 = *(long double*)&FPreg(rs2);

#endif

break;

}

/* ÇÜΨ¤òÀßÄê */

if (sip->si_code == FPE_FLTOVF) {

fscl = scalbnf(1.0f, -96);

dscl = scalbn(1.0, -768);

qscl = scalbnl(1.0, -12288);

} else {

fscl = scalbnf(1.0f, 96);

dscl = scalbn(1.0, 768);

qscl = scalbnl(1.0, 12288);

}

/* ¥È¥é¥Ã¥×¤ò̵¸ú¤Ë¤·¤Æ´ð½à²½(¥¹¥±¡¼¥ë)¤µ¤ì¤¿·ë²Ì¤òÀ¸À® */

fpsetmask(0);

switch (opf) {

case 0x41: /* ñÀºÅ٤βû» */

fd = fscl * (fscl * fs1 + fscl * fs2);

break;

case 0x42: /* ÇÜÀºÅ٤βû» */

dd = dscl * (dscl * ds1 + dscl * ds2);

break;

case 0x43: /* 4 ÇÜÀºÅ٤βû» */

qd = qscl * (qscl * qs1 + qscl * qs2);

break;

case 0x45: /* ñÀºÅ٤θº»» */

fd = fscl * (fscl * fs1 - fscl * fs2);

break;

case 0x46: /* ÇÜÀºÅ٤θº»» */

dd = dscl * (dscl * ds1 - dscl * ds2);

break;

case 0x47: /* 4 ÇÜÀºÅ٤θº»» */

qd = qscl * (qscl * qs1 - qscl * qs2);

break;

case 0x49: /* ñÀºÅ٤ξ軻 */

fd = (fscl * fs1) * (fscl * fs2);

break;

case 0x4a: /* ÇÜÀºÅ٤ξ軻 */

dd = (dscl * ds1) * (dscl * ds2);

break;

case 0x4b: /* 4 ÇÜÀºÅ٤ξ軻 */

qd = (qscl * qs1) * (qscl * qs2);

break;

case 0x4d: /* ñÀºÅ٤νü»» */

fd = (fscl * fs1) / (fs2 / fscl);

break;

case 0x4e: /* ÇÜÀºÅ٤νü»» */

dd = (dscl * ds1) / (ds2 / dscl);

break;

case 0x4f: /* 4 ÇÜÀºÅ٤νü»» */

qd = (qscl * qs1) / (qs2 / dscl);

break;

case 0xc6: /* ÇÜÀºÅÙ¤òñÀºÅÙ¤ËÊÑ´¹ */

fd = (float) (fscl * (fscl * ds1));

break;

case 0xc7: /* 4 ÇÜÀºÅÙ¤òñÀºÅÙ¤ËÊÑ´¹ */

fd = (float) (fscl * (fscl * qs1));

break;

case 0xcb: /* 4 ÇÜÀºÅÙ¤òÇÜÀºÅÙ¤ËÊÑ´¹ */

dd = (double) (dscl * (dscl * qs1));

break;

}

/* °¸Àè¤Ë·ë²Ì¤ò³ÊǼ */

if (opf & 0x80) {

/* ÊÑ´¹±é»» */

if (opf == 0xcb) {

/* 4 ÇÜÀºÅÙ¤òÇÜÀºÅÙ¤ËÊÑ´¹ */

#ifdef V8PLUS

if (rd & 1)

{

assert(uap->uc_mcontext.xrs.xrs_id == XRS_ID);

*(double*)&FPxreg(rd & 0x1e) = dd;

}

else

*(double*)&FPreg(rd) = dd;

#else

*(double*)&FPreg(rd) = dd;

#endif

} else

/* 4 ÇÜÀºÅÙ/ÇÜÀºÅÙ¤òñÀºÅÙ¤ËÊÑ´¹ */

*(float*)&FPreg(rd) = fd;

} else {

/* »»½Ñ±é»» */

switch (opf & 3) {

case 1: /* ñÀºÅÙ */

*(float*)&FPreg(rd) = fd;

break;

case 2: /* ÇÜÀºÅÙ */

#ifdef V8PLUS

if (rd & 1)

{

assert(uap->uc_mcontext.xrs.xrs_id == XRS_ID);

*(double*)&FPxreg(rd & 0x1e) = dd;

}

else

*(double*)&FPreg(rd) = dd;

#else

*(double*)&FPreg(rd) = dd;

#endif

break;

case 3: /* 4 ÇÜÀºÅÙ */

#ifdef V8PLUS

if (rd & 1)

{

assert(uap->uc_mcontext.xrs.xrs_id == XRS_ID);

*(long double*)&FPxreg(rd & 0x1e) = qd;

}

else

*(long double*)&FPreg(rd & 0x1e) = qd;

#else

*(long double*)&FPreg(rd & 0x1e) = qd;

#endif

break;

}

}

}

int

main()

{

volatile float a, b;

volatile double x, y;

ieee_handler("set", "underflow", ieee_trapped_default);

ieee_handler("set", "overflow", ieee_trapped_default);

a = b = 1.0e30f;

a *= b; /* ¥ª¡¼¥Ð¡¼¥Õ¥í¡¼ ; ŬÀڤʿô¤Ë¥é¥Ã¥×¤µ¤ì¤ë */

printf( "%g\n", a );

a /= b;

printf( "%g\n", a );

a /= b; /* ¥¢¥ó¥À¡¼¥Õ¥í¡¼ ; µÕÊý¸þ¤Ë¥é¥Ã¥×¤µ¤ì¤ë */

printf( "%g\n", a );

x = y = 1.0e300;

x *= y; /* ¥ª¡¼¥Ð¡¼¥Õ¥í¡¼ ; ŬÀڤʿô¤Ë¥é¥Ã¥×¤µ¤ì¤ë */

printf( "%g\n", x );

x /= y;

printf( "%g\n", x );

x /= y; /* ¥¢¥ó¥À¡¼¥Õ¥í¡¼ ; µÕÊý¸þ¤Ë¥é¥Ã¥×¤µ¤ì¤ë */

printf( "%g\n", x );

ieee_retrospective(stdout);

return 0;

}

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#include <stdio.h>

#include <ieeefp.h>

#include <math.h>

#include <sunmath.h>

#include <siginfo.h>

#include <ucontext.h>

/* Êݸ¤µ¤ì¤¿ fp ´Ä¶­¤Ø¤Î¥ª¥Õ¥»¥Ã¥È */

#define CW 0 /* À©¸æ¥ï¡¼¥É */

#define SW 1 /* ¥¹¥Æ¡¼¥¿¥¹¥ï¡¼¥É */

#define TW 2 /* ¥¿¥°¥ï¡¼¥É */

#define OP 4 /* ±é»»¥³¡¼¥É */

#define EA 5 /* ¥ª¥Ú¥é¥ó¥É¤Î¥¢¥É¥ì¥¹ */

#define FPenv(x) uap->uc_mcontext.fpregs.fp_reg_set. fpchip_state.state[(x)]

#define FPreg(x) *(long double *)(10*(x)+(char*)&uap-> uc_mcontext.fpregs.fp_reg_set.fpchip_state.state[7])

/*

* ¥È¥é¥Ã¥×¤µ¤ì¤¿¥¢¥ó¥À¡¼¥Õ¥í¡¼¤Þ¤¿¤Ï¥ª¡¼¥Ð¡¼¥Õ¥í¡¼¤Ë¤Ä¤¤¤Æ * IEEE 754 ¥Ç¥Õ¥©¥ë¥È¤Î·ë²Ì¤òÄó¶¡

*/

void

ieee_trapped_default(int sig, siginfo_t *sip, ucontext_t *uap)

{

double dscl;

float fscl;

unsigned sw, op, top;

int mask, e;

/* ¥È¥é¥Ã¥×¤µ¤ì¤Ê¤«¤Ã¤¿Îã³°¤Î¥Õ¥é¥°¤òÊݸ */

sw = uap->uc_mcontext.fpregs.fp_reg_set.fpchip_state.status;

FPenv(SW) |= (sw & (FPenv(CW) & 0x3f));

/* Îã³°¤È¤Ê¤Ã¤¿Ì¿Î᤬µ­²±Îΰè¤Ë¤¢¤ë¾ì¹ç¡¢¥¹¥¿¥Ã¥¯¤ò°ìÈÖ¾å¤Ë ´ð½à²½(¥¹¥±¡¼¥ë)¤·¤Æ³ÊǼ¤·¡¢É¬Íפ˱þ¤¸¤Æ¥¹¥¿¥Ã¥¯¤ò¥Ý¥Ã¥× */

fpsetmask(0);

op = FPenv(OP) >> 16;

switch (op & 0x7f8) {

case 0x110:

case 0x118:

case 0x150:

case 0x158:

case 0x190:

case 0x198:

fscl = scalbnf(1.0f, (sip->si_code == FPE_FLTOVF)? -96 : 96);

*(float *)FPenv(EA) = (FPreg(0) * fscl) * fscl;

if (op & 8) {

/* ¥¹¥¿¥Ã¥¯¤ò¥Ý¥Ã¥×¤¹¤ë */

FPreg(0) = FPreg(1);

FPreg(1) = FPreg(2);

FPreg(2) = FPreg(3);

FPreg(3) = FPreg(4);

FPreg(4) = FPreg(5);

FPreg(5) = FPreg(6);

FPreg(6) = FPreg(7);

top = (FPenv(SW) >> 10) & 0xe;

FPenv(TW) |= (3 << top);

top = (top + 2) & 0xe;

FPenv(SW) = (FPenv(SW) & ~0x3800) | (top << 10);

}

break;

case 0x510:

case 0x518:

case 0x550:

case 0x558:

case 0x590:

case 0x598:

dscl = scalbn(1.0, (sip->si_code == FPE_FLTOVF)? -768 : 768);

*(double *)FPenv(EA) = (FPreg(0) * dscl) * dscl;

if (op & 8) {

/* ¥¹¥¿¥Ã¥¯¤ò¥Ý¥Ã¥×¤¹¤ë */

FPreg(0) = FPreg(1);

FPreg(1) = FPreg(2);

FPreg(2) = FPreg(3);

FPreg(3) = FPreg(4);

FPreg(4) = FPreg(5);

FPreg(5) = FPreg(6);

FPreg(6) = FPreg(7);

top = (FPenv(SW) >> 10) & 0xe;

FPenv(TW) |= (3 << top);

top = (top + 2) & 0xe;

FPenv(SW) = (FPenv(SW) & ~0x3800) | (top << 10);

}

break;

}

}

int

main()

{

volatile float a, b;

volatile double x, y;

ieee_handler("set", "underflow", ieee_trapped_default);

ieee_handler("set", "overflow", ieee_trapped_default);

a = b = 1.0e30f;

a *= b;

printf( "%g\n", a );

a /= b;

printf( "%g\n", a );

a /= b;

printf( "%g\n", a );

x = y = 1.0e300;

x *= y;

printf( "%g\n", x );

x /= y;

printf( "%g\n", x );

x /= y;

printf( "%g\n", x );

ieee_retrospective(stdout);

return 0;

}

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#include <stdio.h> #include <fenv.h> void handler(int ex, fex_info_t *info) { info->res.type = fex_nodata; } int main() { volatile float a, b; volatile double x, y; fex_set_log(stderr); fex_set_handling(FEX_UNDERFLOW | FEX_OVERFLOW, FEX_CUSTOM, handler); a = b = 1.0e30f; a *= b; /* ¥ª¡¼¥Ð¡¼¥Õ¥í¡¼ ; ŬÀڤʿôÃͤ˥é¥Ã¥×¤µ¤ì¤ë */ printf("%g\n", a); a /= b; printf("%g\n", a); a /= b; /* ¥¢¥ó¥À¡¼¥Õ¥í¡¼ ; µÕÊý¸þ¤Ë¥é¥Ã¥×¤µ¤ì¤ë */ printf("%g\n", a); x = y = 1.0e300; x *= y; /* ¥ª¡¼¥Ð¡¼¥Õ¥í¡¼ ; ŬÀڤʿôÃͤ˥é¥Ã¥×¤µ¤ì¤ë */ printf("%g\n", x); x /= y; printf("%g\n", x); x /= y; /* ¥¢¥ó¥À¡¼¥Õ¥í¡¼ ; µÕÊý¸þ¤Ë¥é¥Ã¥×¤µ¤ì¤ë */ printf("%g\n", x); return 0; }

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Floating point overflow at 0x00010924 main, handler: handler 0x00010928 main 159.309 1.59309e-28 Floating point underflow at 0x00010994 main, handler: handler 0x00010998 main 1 Floating point overflow at 0x000109e4 main, handler: handler 0x000109e8 main 4.14884e+137 4.14884e-163 Floating point underflow at 0x00010a4c main, handler: handler 0x00010a50 main 1