diff options
Diffstat (limited to 'sys/gnu/arch/i386/fpemul/fpu_aux.c')
| -rw-r--r-- | sys/gnu/arch/i386/fpemul/fpu_aux.c | 233 |
1 files changed, 233 insertions, 0 deletions
diff --git a/sys/gnu/arch/i386/fpemul/fpu_aux.c b/sys/gnu/arch/i386/fpemul/fpu_aux.c new file mode 100644 index 00000000000..ae7df9a593a --- /dev/null +++ b/sys/gnu/arch/i386/fpemul/fpu_aux.c @@ -0,0 +1,233 @@ +/* $OpenBSD: fpu_aux.c,v 1.1 1996/08/27 10:32:45 downsj Exp $ */ +/* + * fpu_aux.c + * + * Code to implement some of the FPU auxiliary 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_aux.c,v 1.4 1995/12/14 09:50:21 phk Exp $ + * + */ + + +#include <sys/param.h> +#include <sys/proc.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> + + +static void +fclex(void) +{ + status_word &= ~(SW_Backward | SW_Summary | SW_Stack_Fault | SW_Precision | + SW_Underflow | SW_Overflow | SW_Zero_Div | SW_Denorm_Op | + SW_Invalid); + FPU_entry_eip = ip_offset; /* We want no net effect */ +} +/* Needs to be externally visible */ +void +finit() +{ + int r; + control_word = 0x037f; + status_word = 0; + top = 0; /* We don't keep top in the status word + * internally. */ + for (r = 0; r < 8; r++) { + regs[r].tag = TW_Empty; + } + FPU_entry_eip = ip_offset = 0; +} + +static FUNC finit_table[] = { + Un_impl, Un_impl, fclex, finit, Un_impl, Un_impl, Un_impl, Un_impl +}; + +void +finit_() +{ + (finit_table[FPU_rm]) (); +} + + +static void +fstsw_ax(void) +{ + + status_word &= ~SW_Top; + status_word |= (top & 7) << SW_Top_Shift; + + *(short *) &FPU_EAX = status_word; + +} + +static FUNC fstsw_table[] = { + fstsw_ax, Un_impl, Un_impl, Un_impl, Un_impl, Un_impl, Un_impl, Un_impl +}; + +void +fstsw_() +{ + (fstsw_table[FPU_rm]) (); +} + + + +static void +fnop(void) +{ +} + +static FUNC fp_nop_table[] = { + fnop, Un_impl, Un_impl, Un_impl, Un_impl, Un_impl, Un_impl, Un_impl +}; + +void +fp_nop() +{ + (fp_nop_table[FPU_rm]) (); +} + + +void +fld_i_() +{ + FPU_REG *st_new_ptr; + + if (STACK_OVERFLOW) { + stack_overflow(); + return; + } + /* fld st(i) */ + if (NOT_EMPTY(FPU_rm)) { + reg_move(&st(FPU_rm), st_new_ptr); + push(); + } else { + if (control_word & EX_Invalid) { + /* The masked response */ + push(); + stack_underflow(); + } else + EXCEPTION(EX_StackUnder); + } + +} + + +void +fxch_i() +{ + /* fxch st(i) */ + FPU_REG t; + register FPU_REG *sti_ptr = &st(FPU_rm); + + if (FPU_st0_tag == TW_Empty) { + if (sti_ptr->tag == TW_Empty) { + stack_underflow(); + stack_underflow_i(FPU_rm); + return; + } + reg_move(sti_ptr, FPU_st0_ptr); + stack_underflow_i(FPU_rm); + return; + } + if (sti_ptr->tag == TW_Empty) { + reg_move(FPU_st0_ptr, sti_ptr); + stack_underflow(); + return; + } + reg_move(FPU_st0_ptr, &t); + reg_move(sti_ptr, FPU_st0_ptr); + reg_move(&t, sti_ptr); +} + + +void +ffree_() +{ + /* ffree st(i) */ + st(FPU_rm).tag = TW_Empty; +} + + +void +ffreep() +{ + /* ffree st(i) + pop - unofficial code */ + st(FPU_rm).tag = TW_Empty; + pop(); +} + + +void +fst_i_() +{ + /* fst st(i) */ + reg_move(FPU_st0_ptr, &st(FPU_rm)); +} + + +void +fstp_i() +{ + /* fstp st(i) */ + reg_move(FPU_st0_ptr, &st(FPU_rm)); + pop(); +} |