/* $OpenBSD: fpu_etc.c,v 1.2 2003/07/30 21:30:31 jason Exp $ */ /* * fpu_etc.c * * Implement a few FPU instructions. * * * Copyright (C) 1992,1993,1994 * W. Metzenthen, 22 Parker St, Ormond, Vic 3163, * Australia. E-mail billm@vaxc.cc.monash.edu.au * All rights reserved. * * This copyright notice covers the redistribution and use of the * FPU emulator developed by W. Metzenthen. It covers only its use * in the 386BSD, FreeBSD and NetBSD operating systems. Any other * use is not permitted under this copyright. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must include information specifying * that source code for the emulator is freely available and include * either: * a) an offer to provide the source code for a nominal distribution * fee, or * b) list at least two alternative methods whereby the source * can be obtained, e.g. a publically accessible bulletin board * and an anonymous ftp site from which the software can be * downloaded. * 3. All advertising materials specifically mentioning features or use of * this emulator must acknowledge that it was developed by W. Metzenthen. * 4. The name of W. Metzenthen may not be used to endorse or promote * products derived from this software without specific prior written * permission. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL * W. METZENTHEN BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * * The purpose of this copyright, based upon the Berkeley copyright, is to * ensure that the covered software remains freely available to everyone. * * The software (with necessary differences) is also available, but under * the terms of the GNU copyleft, for the Linux operating system and for * the djgpp ms-dos extender. * * W. Metzenthen June 1994. * * * $FreeBSD: fpu_etc.c,v 1.3 1994/06/10 07:44:24 rich Exp $ * */ #include <sys/param.h> #include <sys/proc.h> #include <sys/user.h> #include <machine/cpu.h> #include <machine/pcb.h> #include <gnu/arch/i386/fpemul/fpu_emu.h> #include <gnu/arch/i386/fpemul/fpu_system.h> #include <gnu/arch/i386/fpemul/exception.h> #include <gnu/arch/i386/fpemul/status_w.h> #include <gnu/arch/i386/fpemul/reg_constant.h> static void fchs(void) { if (NOT_EMPTY_0) { FPU_st0_ptr->sign ^= SIGN_POS ^ SIGN_NEG; status_word &= ~SW_C1; } else stack_underflow(); } static void fabs(void) { if (FPU_st0_tag ^ TW_Empty) { FPU_st0_ptr->sign = SIGN_POS; status_word &= ~SW_C1; } else stack_underflow(); } static void ftst_(void) { switch (FPU_st0_tag) { case TW_Zero: setcc(SW_C3); break; case TW_Valid: #ifdef DENORM_OPERAND if ((FPU_st0_ptr->exp <= EXP_UNDER) && (denormal_operand())) return; #endif /* DENORM_OPERAND */ if (FPU_st0_ptr->sign == SIGN_POS) setcc(0); else setcc(SW_C0); break; case TW_NaN: setcc(SW_C0 | SW_C2 | SW_C3); /* Operand is not comparable */ EXCEPTION(EX_Invalid); break; case TW_Infinity: if (FPU_st0_ptr->sign == SIGN_POS) setcc(0); else setcc(SW_C0); EXCEPTION(EX_Invalid); break; case TW_Empty: setcc(SW_C0 | SW_C2 | SW_C3); EXCEPTION(EX_StackUnder); break; default: setcc(SW_C0 | SW_C2 | SW_C3); /* Operand is not comparable */ EXCEPTION(EX_INTERNAL | 0x14); break; } } static void fxam(void) { int c = 0; switch (FPU_st0_tag) { case TW_Empty: c = SW_C3 | SW_C0; break; case TW_Zero: c = SW_C3; break; case TW_Valid: /* This will need to be changed if TW_Denormal is ever used. */ if (FPU_st0_ptr->exp <= EXP_UNDER) c = SW_C2 | SW_C3; /* Denormal */ else c = SW_C3; break; case TW_NaN: c = SW_C0; break; case TW_Infinity: c = SW_C2 | SW_C0; break; } if (FPU_st0_ptr->sign == SIGN_NEG) c |= SW_C1; setcc(c); } static FUNC fp_etc_table[] = { fchs, fabs, Un_impl, Un_impl, ftst_, fxam, Un_impl, Un_impl }; void fp_etc() { (fp_etc_table[FPU_rm]) (); }