/*---------------------------------------------------------------------------+ | errors.c | | | | The error handling functions for wm-FPU-emu | | | | Copyright (C) 1992 W. Metzenthen, 22 Parker St, Ormond, Vic 3163, | | Australia. E-mail apm233m@vaxc.cc.monash.edu.au | | | | | +---------------------------------------------------------------------------*/ #include #include #include "fpu_system.h" #include "exception.h" #include "fpu_emu.h" #include "status_w.h" #include "control_w.h" #include "reg_constant.h" #include "version.h" extern unsigned char FPU_lookahead; /* */ #undef PRINT_MESSAGES /* */ void Un_impl(void) { unsigned char byte1 = get_fs_byte((unsigned char *) FPU_ORIG_EIP); printk("Unimplemented FPU Opcode at eip=%p : %02x ", FPU_ORIG_EIP, byte1); if (FPU_modrm >= 0300) printk("%02x (%02x+%d)\n", FPU_modrm, FPU_modrm & 0xf8, FPU_modrm & 7); else printk("/%d\n", (FPU_modrm >> 3) & 7); EXCEPTION(EX_Invalid); } void emu_printall() { int i; static char *tag_desc[] = { "Valid", "Zero", "ERROR", "ERROR", "DeNorm", "Inf", "NaN", "Empty" }; unsigned char byte1 = get_fs_byte((unsigned char *) FPU_ORIG_EIP); #ifdef DEBUGGING if ( status_word & SW_B ) printk("SW: backward compatibility (=ES)\n"); if ( status_word & SW_C3 ) printk("SW: condition bit 3\n"); if ( status_word & SW_C2 ) printk("SW: condition bit 2\n"); if ( status_word & SW_C1 ) printk("SW: condition bit 1\n"); if ( status_word & SW_C0 ) printk("SW: condition bit 0\n"); if ( status_word & SW_ES ) printk("SW: exception summary\n"); if ( status_word & SW_SF ) printk("SW: stack fault\n"); if ( status_word & SW_PE ) printk("SW: loss of precision\n"); if ( status_word & SW_UE ) printk("SW: underflow\n"); if ( status_word & SW_OE ) printk("SW: overflow\n"); if ( status_word & SW_ZE ) printk("SW: divide by zero\n"); if ( status_word & SW_DE ) printk("SW: denormalized operand\n"); if ( status_word & SW_IE ) printk("SW: invalid operation\n"); #endif DEBUGGING status_word = status_word & ~SW_TOP; status_word |= (top&7) << SW_TOPS; printk("At %p: %02x ", FPU_ORIG_EIP, byte1); if (FPU_modrm >= 0300) printk("%02x (%02x+%d)\n", FPU_modrm, FPU_modrm & 0xf8, FPU_modrm & 7); else printk("/%d, mod=%d rm=%d\n", (FPU_modrm >> 3) & 7, (FPU_modrm >> 6) & 3, FPU_modrm & 7); printk(" SW: b=%d st=%d es=%d sf=%d cc=%d%d%d%d ef=%d%d%d%d%d%d\n", status_word & 0x8000 ? 1 : 0, /* busy */ (status_word & 0x3800) >> 11, /* stack top pointer */ status_word & 0x80 ? 1 : 0, /* Error summary status */ status_word & 0x40 ? 1 : 0, /* Stack flag */ status_word & SW_C3?1:0, status_word & SW_C2?1:0, /* cc */ status_word & SW_C1?1:0, status_word & SW_C0?1:0, /* cc */ status_word & SW_PE?1:0, status_word & SW_UE?1:0, /* exception fl */ status_word & SW_OE?1:0, status_word & SW_ZE?1:0, /* exception fl */ status_word & SW_DE?1:0, status_word & SW_IE?1:0); /* exception fl */ printk(" CW: ic=%d rc=%d%d pc=%d%d iem=%d ef=%d%d%d%d%d%d\n", control_word & 0x1000 ? 1 : 0, (control_word & 0x800) >> 11, (control_word & 0x400) >> 10, (control_word & 0x200) >> 9, (control_word & 0x100) >> 8, control_word & 0x80 ? 1 : 0, control_word & SW_PE?1:0, control_word & SW_UE?1:0, /* exception */ control_word & SW_OE?1:0, control_word & SW_ZE?1:0, /* exception */ control_word & SW_DE?1:0, control_word & SW_IE?1:0); /* exception */ for ( i = 0; i < 8; i++ ) { struct reg *r = &st(i); switch (r->tag) { case TW_Empty: continue; break; case TW_Zero: printk("st(%d) %c .0000 0000 0000 0000 ", i, r->sign ? '-' : '+'); break; case TW_Valid: case TW_NaN: case TW_Denormal: case TW_Infinity: printk("st(%d) %c .%04x %04x %04x %04x e%+-6d ", i, r->sign ? '-' : '+', (long)(r->sigh >> 16), (long)(r->sigh & 0xFFFF), (long)(r->sigl >> 16), (long)(r->sigl & 0xFFFF), r->exp - EXP_BIAS + 1); break; default: printk("Whoops! Error in errors.c "); break; } printk("%s\n", tag_desc[(int) (unsigned) r->tag]); } printk("[data] %c .%04x %04x %04x %04x e%+-6d ", FPU_loaded_data.sign ? '-' : '+', (long)(FPU_loaded_data.sigh >> 16), (long)(FPU_loaded_data.sigh & 0xFFFF), (long)(FPU_loaded_data.sigl >> 16), (long)(FPU_loaded_data.sigl & 0xFFFF), FPU_loaded_data.exp - EXP_BIAS + 1); printk("%s\n", tag_desc[(int) (unsigned) FPU_loaded_data.tag]); } static struct { int type; char *name; } exception_names[] = { EX_StackOver, "stack overflow", EX_StackUnder, "stack underflow", EX_Precision, "loss of precision", EX_Underflow, "underflow", EX_Overflow, "overflow", EX_ZeroDiv, "divide by zero", EX_Denormal, "denormalized operand", EX_Invalid, "invalid operation", EX_INTERNAL, "INTERNAL BUG in "FPU_VERSION, 0,0 }; /* EX_INTERNAL is always given with a code which indicates where the error was detected. Internal error types: 0x14 in e14.c 0x1nn in a *.c file: 0x101 in reg_add_sub.c 0x102 in reg_mul.c 0x103 in poly_sin.c 0x104 in poly_tan.c 0x105 in reg_mul.c 0x106 in reg_mov.c 0x107 in fpu_trig.c 0x108 in reg_compare.c 0x109 in reg_compare.c 0x110 in reg_add_sub.c 0x111 in interface.c 0x112 in fpu_trig.c 0x113 in reg_add_sub.c 0x114 in reg_ld_str.c 0x115 in fpu_trig.c 0x116 in fpu_trig.c 0x117 in fpu_trig.c 0x118 in fpu_trig.c 0x119 in fpu_trig.c 0x120 in poly_atan.c 0x121 in reg_compare.c 0x122 in reg_compare.c 0x123 in reg_compare.c 0x2nn in an *.s file: 0x201 in reg_u_add.S 0x202 in reg_u_div.S 0x203 in reg_u_div.S 0x204 in reg_u_div.S 0x205 in reg_u_mul.S 0x206 in reg_u_sub.S 0x207 in wm_sqrt.S 0x208 in reg_div.S 0x209 in reg_u_sub.S 0x210 in reg_u_sub.S 0x211 in reg_u_sub.S 0x212 in reg_u_sub.S */ void exception(int n) { int i, int_type; if ( n & EX_INTERNAL ) { int_type = n - EX_INTERNAL; n = EX_INTERNAL; /* Set lots of exception bits! */ status_word |= (0x3f | EX_ErrorSummary | FPU_BUSY); } else { /* Set the corresponding exception bit */ status_word |= (n | EX_ErrorSummary | FPU_BUSY); if (n == EX_StackUnder) /* Stack underflow */ /* This bit distinguishes over- from underflow */ status_word &= ~SW_C1; } if ( (~control_word & n & CW_EXM) || (n == EX_INTERNAL) ) { #ifdef PRINT_MESSAGES /* My message from the sponsor */ printk(FPU_VERSION" "__DATE__" (C) W. Metzenthen.\r\n"); #endif PRINT_MESSAGES /* Get a name string for error reporting */ for (i=0; exception_names[i].type; i++) if (exception_names[i].type == n) break; if (exception_names[i].type) { #ifdef PRINT_MESSAGES printk("FP Exception: %s!\n", exception_names[i].name); #endif PRINT_MESSAGES } else printk("FP emulator: Unknown Exception: 0x%04x!\n", n); if ( n == EX_INTERNAL ) { printk("FP emulator: Internal error type 0x%04x\n", int_type); emu_printall(); } #ifdef PRINT_MESSAGES else emu_printall(); #endif PRINT_MESSAGES send_sig(SIGFPE, current, 1); } #ifdef __DEBUG__ math_abort(FPU_info,SIGFPE); #endif __DEBUG__ /* Cause the look-ahead mechanism to terminate */ FPU_lookahead = 0; } /* Real operation attempted on two operands, one a NaN */ void real_2op_NaN(REG *a, REG *b, REG *dest) { REG *x; x = a; if (a->tag == TW_NaN) { if (b->tag == TW_NaN) { /* find the "larger" */ if ( *(long long *)&(a->sigl) < *(long long *)&(b->sigl) ) x = b; } /* else return the quiet version of the NaN in a */ } else if (b->tag == TW_NaN) { x = b; } #ifdef PARANOID else { EXCEPTION(EX_INTERNAL|0x113); x = &CONST_QNaN; } #endif PARANOID if ( control_word & EX_Invalid ) { /* The masked response */ reg_move(x, dest); /* ensure a Quiet NaN */ dest->sigh |= 0x40000000; } EXCEPTION(EX_Invalid); return; } /* Invalid arith operation on valid registers */ void arith_invalid(REG *dest) { if ( control_word & EX_Invalid ) { /* The masked response */ reg_move(&CONST_QNaN, dest); } EXCEPTION(EX_Invalid); return; } /* Divide a finite number by zero */ void divide_by_zero(int sign, REG *dest) { if ( control_word & EX_ZeroDiv ) { /* The masked response */ reg_move(&CONST_INF, dest); dest->sign = (unsigned char)sign; } EXCEPTION(EX_ZeroDiv); return; } void arith_overflow(REG *dest) { if ( control_word & EX_Overflow ) { char sign; /* The masked response */ sign = dest->sign; reg_move(&CONST_INF, dest); dest->sign = sign; } else { /* Subtract the magic number from the exponent */ dest->exp -= (3 * (1 << 13)); } EXCEPTION(EX_Overflow); return; } void arith_underflow(REG *dest) { if ( control_word & EX_Underflow ) { /* The masked response */ if ( dest->exp <= EXP_UNDER - 63 ) reg_move(&CONST_Z, dest); } else { /* Add the magic number to the exponent */ dest->exp += (3 * (1 << 13)); } EXCEPTION(EX_Underflow); return; } void stack_overflow(void) { if ( control_word & EX_Invalid ) { /* The masked response */ top--; reg_move(&CONST_QNaN, st0_ptr = &st(0)); } EXCEPTION(EX_StackOver); return; } void stack_underflow(void) { if ( control_word & EX_Invalid ) { /* The masked response */ reg_move(&CONST_QNaN, st0_ptr); } EXCEPTION(EX_StackUnder); return; }