diff options
Diffstat (limited to 'sys/gnu/i386/fpemul/fpu_entry.c')
| -rw-r--r-- | sys/gnu/i386/fpemul/fpu_entry.c | 483 |
1 files changed, 0 insertions, 483 deletions
diff --git a/sys/gnu/i386/fpemul/fpu_entry.c b/sys/gnu/i386/fpemul/fpu_entry.c deleted file mode 100644 index edbe94d..0000000 --- a/sys/gnu/i386/fpemul/fpu_entry.c +++ /dev/null @@ -1,483 +0,0 @@ -/* - * fpu_entry.c - * - * The entry function for wm-FPU-emu - * - * - * 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. - * - * $Id: fpu_entry.c,v 1.5 1994/08/30 20:18:52 davidg Exp $ - * - */ - -/*---------------------------------------------------------------------------+ - | Note: | - | The file contains code which accesses user memory. | - | Emulator static data may change when user memory is accessed, due to | - | other processes using the emulator while swapping is in progress. | - +---------------------------------------------------------------------------*/ - -/*---------------------------------------------------------------------------+ - | math_emulate() is the sole entry point for wm-FPU-emu | - +---------------------------------------------------------------------------*/ - - -#include "param.h" -#include "systm.h" -#include "proc.h" -#include "machine/cpu.h" -#include "machine/pcb.h" - -#include "fpu_emu.h" -#include "fpu_system.h" -#include "exception.h" -#include "control_w.h" -#include "status_w.h" - - -#define __BAD__ Un_impl /* Not implemented */ - -#define FPU_LOOKAHEAD 1 /* For performance boost */ - -#if FPU_LOOKAHEAD != 0 /* I think thet we have to limit the */ -#define LOOKAHEAD_LIMIT 7 /* Max number of lookahead instructions*/ -#endif /* Or else a prog consisting of a million */ - /* fnops will spend all its time in kernel*/ - -#ifndef NO_UNDOC_CODE /* Un-documented FPU op-codes supported by - * default. */ - -/* WARNING: These codes are not documented by Intel in their 80486 manual - and may not work on FPU clones or later Intel FPUs. */ - -/* Changes to support the un-doc codes provided by Linus Torvalds. */ - -#define _d9_d8_ fstp_i /* unofficial code (19) */ -#define _dc_d0_ fcom_st /* unofficial code (14) */ -#define _dc_d8_ fcompst /* unofficial code (1c) */ -#define _dd_c8_ fxch_i /* unofficial code (0d) */ -#define _de_d0_ fcompst /* unofficial code (16) */ -#define _df_c0_ ffreep /* unofficial code (07) ffree + pop */ -#define _df_c8_ fxch_i /* unofficial code (0f) */ -#define _df_d0_ fstp_i /* unofficial code (17) */ -#define _df_d8_ fstp_i /* unofficial code (1f) */ - -static FUNC st_instr_table[64] = { - fadd__, fld_i_, __BAD__, __BAD__, fadd_i, ffree_, faddp_, _df_c0_, - fmul__, fxch_i, __BAD__, __BAD__, fmul_i, _dd_c8_, fmulp_, _df_c8_, - fcom_st, fp_nop, __BAD__, __BAD__, _dc_d0_, fst_i_, _de_d0_, _df_d0_, - fcompst, _d9_d8_, __BAD__, __BAD__, _dc_d8_, fstp_i, fcompp, _df_d8_, - fsub__, fp_etc, __BAD__, finit_, fsubri, fucom_, fsubrp, fstsw_, - fsubr_, fconst, fucompp, __BAD__, fsub_i, fucomp, fsubp_, __BAD__, - fdiv__, trig_a, __BAD__, __BAD__, fdivri, __BAD__, fdivrp, __BAD__, - fdivr_, trig_b, __BAD__, __BAD__, fdiv_i, __BAD__, fdivp_, __BAD__, -}; -#else /* Support only documented FPU op-codes */ - -static FUNC st_instr_table[64] = { - fadd__, fld_i_, __BAD__, __BAD__, fadd_i, ffree_, faddp_, __BAD__, - fmul__, fxch_i, __BAD__, __BAD__, fmul_i, __BAD__, fmulp_, __BAD__, - fcom_st, fp_nop, __BAD__, __BAD__, __BAD__, fst_i_, __BAD__, __BAD__, - fcompst, __BAD__, __BAD__, __BAD__, __BAD__, fstp_i, fcompp, __BAD__, - fsub__, fp_etc, __BAD__, finit_, fsubri, fucom_, fsubrp, fstsw_, - fsubr_, fconst, fucompp, __BAD__, fsub_i, fucomp, fsubp_, __BAD__, - fdiv__, trig_a, __BAD__, __BAD__, fdivri, __BAD__, fdivrp, __BAD__, - fdivr_, trig_b, __BAD__, __BAD__, fdiv_i, __BAD__, fdivp_, __BAD__, -}; -#endif /* NO_UNDOC_CODE */ - - -#define _NONE_ 0 /* Take no special action */ -#define _REG0_ 1 /* Need to check for not empty st(0) */ -#define _REGI_ 2 /* Need to check for not empty st(0) and - * st(rm) */ -#define _REGi_ 0 /* Uses st(rm) */ -#define _PUSH_ 3 /* Need to check for space to push onto stack */ -#define _null_ 4 /* Function illegal or not implemented */ -#define _REGIi 5 /* Uses st(0) and st(rm), result to st(rm) */ -#define _REGIp 6 /* Uses st(0) and st(rm), result to st(rm) - * then pop */ -#define _REGIc 0 /* Compare st(0) and st(rm) */ -#define _REGIn 0 /* Uses st(0) and st(rm), but handle checks - * later */ - -#ifndef NO_UNDOC_CODE - -/* Un-documented FPU op-codes supported by default. (see above) */ - -static unsigned char type_table[64] = { - _REGI_, _NONE_, _null_, _null_, _REGIi, _REGi_, _REGIp, _REGi_, - _REGI_, _REGIn, _null_, _null_, _REGIi, _REGI_, _REGIp, _REGI_, - _REGIc, _NONE_, _null_, _null_, _REGIc, _REG0_, _REGIc, _REG0_, - _REGIc, _REG0_, _null_, _null_, _REGIc, _REG0_, _REGIc, _REG0_, - _REGI_, _NONE_, _null_, _NONE_, _REGIi, _REGIc, _REGIp, _NONE_, - _REGI_, _NONE_, _REGIc, _null_, _REGIi, _REGIc, _REGIp, _null_, - _REGI_, _NONE_, _null_, _null_, _REGIi, _null_, _REGIp, _null_, - _REGI_, _NONE_, _null_, _null_, _REGIi, _null_, _REGIp, _null_ -}; -#else /* Support only documented FPU op-codes */ - -static unsigned char type_table[64] = { - _REGI_, _NONE_, _null_, _null_, _REGIi, _REGi_, _REGIp, _null_, - _REGI_, _REGIn, _null_, _null_, _REGIi, _null_, _REGIp, _null_, - _REGIc, _NONE_, _null_, _null_, _null_, _REG0_, _null_, _null_, - _REGIc, _null_, _null_, _null_, _null_, _REG0_, _REGIc, _null_, - _REGI_, _NONE_, _null_, _NONE_, _REGIi, _REGIc, _REGIp, _NONE_, - _REGI_, _NONE_, _REGIc, _null_, _REGIi, _REGIc, _REGIp, _null_, - _REGI_, _NONE_, _null_, _null_, _REGIi, _null_, _REGIp, _null_, - _REGI_, _NONE_, _null_, _null_, _REGIi, _null_, _REGIp, _null_ -}; -#endif /* NO_UNDOC_CODE */ - -/* Be careful when using any of these global variables... - they might change if swapping is triggered */ -unsigned char FPU_rm; -char FPU_st0_tag; -FPU_REG *FPU_st0_ptr; - -#ifdef PARANOID -char emulating = 0; -#endif /* PARANOID */ - -#define bswapw(x) __asm__("xchgb %%al,%%ah":"=a" (x):"0" ((short)x)) -#define math_abort(signo) \ - FPU_EIP = FPU_ORIG_EIP;REENTRANT_CHECK(OFF);return(signo); - -int -math_emulate(struct trapframe * tframe) -{ - - unsigned char FPU_modrm; - unsigned short code; -#ifdef LOOKAHEAD_LIMIT - int lookahead_limit = LOOKAHEAD_LIMIT; -#endif -#ifdef PARANOID - if (emulating) { - printf("ERROR: wm-FPU-emu is not RE-ENTRANT!\n"); - } - REENTRANT_CHECK(ON); -#endif /* PARANOID */ - - if ((((struct pcb *) curproc->p_addr)->pcb_flags & FP_SOFTFP) == 0) { - finit(); - control_word = __INITIAL_NPXCW__; - ((struct pcb *) curproc->p_addr)->pcb_flags |= FP_SOFTFP; - } - FPU_info = tframe; - FPU_ORIG_EIP = FPU_EIP; /* --pink-- */ - - if (FPU_CS != 0x001f) { - printf("math_emulate: %x : %x\n", FPU_CS, FPU_EIP); - panic("FPU emulation in kernel"); - } -#ifdef notyet - /* We cannot handle emulation in v86-mode */ - if (FPU_EFLAGS & 0x00020000) { - FPU_ORIG_EIP = FPU_EIP; - math_abort(FPU_info, SIGILL); - } -#endif - - FPU_lookahead = FPU_LOOKAHEAD; - if (curproc->p_flag & P_TRACED) - FPU_lookahead = 0; - -do_another_FPU_instruction: - - REENTRANT_CHECK(OFF); - code = fuword((u_int *) FPU_EIP); - REENTRANT_CHECK(ON); - if ((code & 0xff) == 0x9b) { /* fwait */ - if (status_word & SW_Summary) - goto do_the_FPU_interrupt; - else { - FPU_EIP++; - goto FPU_instruction_done; - } - } - if (status_word & SW_Summary) { - /* Ignore the error for now if the current instruction is a - * no-wait control instruction */ - /* The 80486 manual contradicts itself on this topic, so I use - * the following list of such instructions until I can check - * on a real 80486: fninit, fnstenv, fnsave, fnstsw, fnstenv, - * fnclex. */ - if (!((((code & 0xf803) == 0xe003) || /* fnclex, fninit, - * fnstsw */ - (((code & 0x3003) == 0x3001) && /* fnsave, fnstcw, - * fnstenv, fnstsw */ - ((code & 0xc000) != 0xc000))))) { - /* This is a guess about what a real FPU might do to - * this bit: */ -/* status_word &= ~SW_Summary; ****/ - - /* We need to simulate the action of the kernel to FPU - * interrupts here. Currently, the "real FPU" part of - * the kernel (0.99.10) clears the exception flags, - * sets the registers to empty, and passes information - * back to the interrupted process via the cs selector - * and operand selector, so we do the same. */ - do_the_FPU_interrupt: - cs_selector &= 0xffff0000; - cs_selector |= (status_word & ~SW_Top) | ((top & 7) << SW_Top_Shift); - operand_selector = tag_word(); - status_word = 0; - top = 0; - { - int r; - for (r = 0; r < 8; r++) { - regs[r].tag = TW_Empty; - } - } - REENTRANT_CHECK(OFF); - math_abort(SIGFPE); - } - } - FPU_entry_eip = FPU_ORIG_EIP = FPU_EIP; - - if ((code & 0xff) == 0x66) { /* size prefix */ - FPU_EIP++; - REENTRANT_CHECK(OFF); - code = fuword((u_int *) FPU_EIP); - REENTRANT_CHECK(ON); - } - FPU_EIP += 2; - - FPU_modrm = code >> 8; - FPU_rm = FPU_modrm & 7; - - if (FPU_modrm < 0300) { - /* All of these instructions use the mod/rm byte to get a data - * address */ - get_address(FPU_modrm); - if (!(code & 1)) { - unsigned short status1 = status_word; - FPU_st0_ptr = &st(0); - FPU_st0_tag = FPU_st0_ptr->tag; - - /* Stack underflow has priority */ - if (NOT_EMPTY_0) { - switch ((code >> 1) & 3) { - case 0: - reg_load_single(); - break; - case 1: - reg_load_int32(); - break; - case 2: - reg_load_double(); - break; - case 3: - reg_load_int16(); - break; - } - - /* No more access to user memory, it is safe - * to use static data now */ - FPU_st0_ptr = &st(0); - FPU_st0_tag = FPU_st0_ptr->tag; - - /* NaN operands have the next priority. */ - /* We have to delay looking at st(0) until - * after loading the data, because that data - * might contain an SNaN */ - if ((FPU_st0_tag == TW_NaN) || - (FPU_loaded_data.tag == TW_NaN)) { - /* Restore the status word; we might - * have loaded a denormal. */ - status_word = status1; - if ((FPU_modrm & 0x30) == 0x10) { - /* fcom or fcomp */ - EXCEPTION(EX_Invalid); - setcc(SW_C3 | SW_C2 | SW_C0); - if (FPU_modrm & 0x08) - pop(); /* fcomp, so we pop. */ - } else - real_2op_NaN(FPU_st0_ptr, &FPU_loaded_data, FPU_st0_ptr); - goto reg_mem_instr_done; - } - switch ((FPU_modrm >> 3) & 7) { - case 0: /* fadd */ - reg_add(FPU_st0_ptr, &FPU_loaded_data, FPU_st0_ptr, control_word); - break; - case 1: /* fmul */ - reg_mul(FPU_st0_ptr, &FPU_loaded_data, FPU_st0_ptr, control_word); - break; - case 2: /* fcom */ - compare_st_data(); - break; - case 3: /* fcomp */ - compare_st_data(); - pop(); - break; - case 4: /* fsub */ - reg_sub(FPU_st0_ptr, &FPU_loaded_data, FPU_st0_ptr, control_word); - break; - case 5: /* fsubr */ - reg_sub(&FPU_loaded_data, FPU_st0_ptr, FPU_st0_ptr, control_word); - break; - case 6: /* fdiv */ - reg_div(FPU_st0_ptr, &FPU_loaded_data, FPU_st0_ptr, control_word); - break; - case 7: /* fdivr */ - if (FPU_st0_tag == TW_Zero) - status_word = status1; /* Undo any denorm tag, - * zero-divide has - * priority. */ - reg_div(&FPU_loaded_data, FPU_st0_ptr, FPU_st0_ptr, control_word); - break; - } - } else { - if ((FPU_modrm & 0x30) == 0x10) { - /* The instruction is fcom or fcomp */ - EXCEPTION(EX_StackUnder); - setcc(SW_C3 | SW_C2 | SW_C0); - if (FPU_modrm & 0x08) - pop(); /* fcomp, Empty or not, - * we pop. */ - } else - stack_underflow(); - } - } else { - load_store_instr(((FPU_modrm & 0x38) | (code & 6)) >> 1); - } - -reg_mem_instr_done: - - data_operand_offset = (unsigned long) FPU_data_address; - } else { - /* None of these instructions access user memory */ - unsigned char instr_index = (FPU_modrm & 0x38) | (code & 7); - - FPU_st0_ptr = &st(0); - FPU_st0_tag = FPU_st0_ptr->tag; - switch (type_table[(int) instr_index]) { - case _NONE_: /* also _REGIc: _REGIn */ - break; - case _REG0_: - if (!NOT_EMPTY_0) { - stack_underflow(); - goto FPU_instruction_done; - } - break; - case _REGIi: - if (!NOT_EMPTY_0 || !NOT_EMPTY(FPU_rm)) { - stack_underflow_i(FPU_rm); - goto FPU_instruction_done; - } - break; - case _REGIp: - if (!NOT_EMPTY_0 || !NOT_EMPTY(FPU_rm)) { - stack_underflow_i(FPU_rm); - pop(); - goto FPU_instruction_done; - } - break; - case _REGI_: - if (!NOT_EMPTY_0 || !NOT_EMPTY(FPU_rm)) { - stack_underflow(); - goto FPU_instruction_done; - } - break; - case _PUSH_: /* Only used by the fld st(i) instruction */ - break; - case _null_: - Un_impl(); - goto FPU_instruction_done; - default: - EXCEPTION(EX_INTERNAL | 0x111); - goto FPU_instruction_done; - } - (*st_instr_table[(int) instr_index]) (); - } - -FPU_instruction_done: - - ip_offset = FPU_entry_eip; - bswapw(code); - *(1 + (unsigned short *) &cs_selector) = code & 0x7ff; - -#ifdef DEBUG - REENTRANT_CHECK(OFF); - emu_printall(); - REENTRANT_CHECK(ON); -#endif /* DEBUG */ -#ifdef LOOKAHEAD_LIMIT -if (--lookahead_limit) -#endif - if (FPU_lookahead) { - unsigned char next; - - /* (This test should generate no machine code) */ - while (1) { - REENTRANT_CHECK(OFF); - next = fubyte((u_char *) FPU_EIP); - REENTRANT_CHECK(ON); - if (((next & 0xf8) == 0xd8) || (next == 0x9b)) { /* fwait */ - goto do_another_FPU_instruction; - } else - if (next == 0x66) { /* size prefix */ - REENTRANT_CHECK(OFF); - next = fubyte((u_char *) (FPU_EIP + 1)); - REENTRANT_CHECK(ON); - if ((next & 0xf8) == 0xd8) { - FPU_EIP++; - goto do_another_FPU_instruction; - } - } - break; - } - } - REENTRANT_CHECK(OFF); - return (0); /* --pink-- */ -} |
