/*---------------------------------------------------------------------------+ | fpu_emu.h | | | | Copyright (C) 1992,1993,1994 | | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, | | Australia. E-mail billm@vaxc.cc.monash.edu.au | | | +---------------------------------------------------------------------------*/ #ifndef _FPU_EMU_H_ #define _FPU_EMU_H_ /* * Define DENORM_OPERAND to make the emulator detect denormals * and use the denormal flag of the status word. Note: this only * affects the flag and corresponding interrupt, the emulator * will always generate denormals and operate upon them as required. */ #define DENORM_OPERAND /* * Define PECULIAR_486 to get a closer approximation to 80486 behaviour, * rather than behaviour which appears to be cleaner. * This is a matter of opinion: for all I know, the 80486 may simply * be complying with the IEEE spec. Maybe one day I'll get to see the * spec... */ #define PECULIAR_486 #ifdef __ASSEMBLER__ #include "fpu_asm.h" #define Const(x) $##x #else #define Const(x) x #endif #define EXP_BIAS Const(0) #define EXP_OVER Const(0x4000) /* smallest invalid large exponent */ #define EXP_UNDER Const(-0x3fff) /* largest invalid small exponent */ #define EXP_Infinity EXP_OVER #define EXP_NaN EXP_OVER #define SIGN_POS Const(0) #define SIGN_NEG Const(1) /* Keep the order TW_Valid, TW_Zero, TW_Denormal */ #define TW_Valid Const(0) /* valid */ #define TW_Zero Const(1) /* zero */ /* The following fold to 2 (Special) in the Tag Word */ /* #define TW_Denormal Const(4) */ /* De-normal */ #define TW_Infinity Const(5) /* + or - infinity */ #define TW_NaN Const(6) /* Not a Number */ #define TW_Empty Const(7) /* empty */ #ifndef __ASSEMBLER__ #include #include #ifdef PARANOID extern char emulating; # define RE_ENTRANT_CHECK_OFF emulating = 0 # define RE_ENTRANT_CHECK_ON emulating = 1 #else # define RE_ENTRANT_CHECK_OFF # define RE_ENTRANT_CHECK_ON #endif PARANOID #define FWAIT_OPCODE 0x9b #define OP_SIZE_PREFIX 0x66 #define ADDR_SIZE_PREFIX 0x67 #define PREFIX_CS 0x2e #define PREFIX_DS 0x3e #define PREFIX_ES 0x26 #define PREFIX_SS 0x36 #define PREFIX_FS 0x64 #define PREFIX_GS 0x65 #define PREFIX_REPE 0xf3 #define PREFIX_REPNE 0xf2 #define PREFIX_LOCK 0xf0 /* These are to defeat the default action, giving the instruction no net effect: */ #define NO_NET_DATA_EFFECT \ { FPU_data_address = (void *)data_operand_offset; \ FPU_data_selector = operand_selector; } #define NO_NET_INSTR_EFFECT \ { FPU_entry_eip = ip_offset; \ FPU_entry_op_cs = cs_selector; } typedef void (*FUNC)(void); typedef struct fpu_reg FPU_REG; typedef struct { unsigned char address_size, segment; } overrides; #define st(x) ( regs[((top+x) &7 )] ) #define STACK_OVERFLOW (st_new_ptr = &st(-1), st_new_ptr->tag != TW_Empty) #define NOT_EMPTY(i) (st(i).tag != TW_Empty) #define NOT_EMPTY_0 (FPU_st0_tag ^ TW_Empty) extern unsigned char FPU_rm; extern char FPU_st0_tag; extern FPU_REG *FPU_st0_ptr; /* ###### These need to be shifted to somewhere safe. */ /* extern void *FPU_data_address; has been shifted */ extern unsigned short FPU_data_selector; extern unsigned long FPU_entry_op_cs; extern FPU_REG FPU_loaded_data; #define pop() { FPU_st0_ptr->tag = TW_Empty; top++; } /* push() does not affect the tags */ #define push() { top--; FPU_st0_ptr = st_new_ptr; } #define reg_move(x, y) { \ *(short *)&((y)->sign) = *(short *)&((x)->sign); \ *(long *)&((y)->exp) = *(long *)&((x)->exp); \ *(long long *)&((y)->sigl) = *(long long *)&((x)->sigl); } #define significand(x) ( ((unsigned long long *)&((x)->sigl))[0] ) /*----- Prototypes for functions written in assembler -----*/ /* extern void reg_move(FPU_REG *a, FPU_REG *b); */ asmlinkage void mul64(unsigned long long const *a, unsigned long long const *b, unsigned long long *result); asmlinkage void poly_div2(unsigned long long *x); asmlinkage void poly_div4(unsigned long long *x); asmlinkage void poly_div16(unsigned long long *x); asmlinkage void polynomial(unsigned accum[], unsigned const x[], unsigned short const terms[][4], int const n); asmlinkage void normalize(FPU_REG *x); asmlinkage void normalize_nuo(FPU_REG *x); asmlinkage int reg_div(FPU_REG const *arg1, FPU_REG const *arg2, FPU_REG *answ, unsigned int control_w); asmlinkage int reg_u_sub(FPU_REG const *arg1, FPU_REG const *arg2, FPU_REG *answ, unsigned int control_w); asmlinkage int reg_u_mul(FPU_REG const *arg1, FPU_REG const *arg2, FPU_REG *answ, unsigned int control_w); asmlinkage int reg_u_div(FPU_REG const *arg1, FPU_REG const *arg2, FPU_REG *answ, unsigned int control_w); asmlinkage int reg_u_add(FPU_REG const *arg1, FPU_REG const *arg2, FPU_REG *answ, unsigned int control_w); asmlinkage int wm_sqrt(FPU_REG *n, unsigned int control_w); asmlinkage unsigned shrx(void *l, unsigned x); asmlinkage unsigned shrxs(void *v, unsigned x); asmlinkage unsigned long div_small(unsigned long long *x, unsigned long y); asmlinkage void round_reg(FPU_REG *arg, unsigned int extent, unsigned int control_w); #ifndef MAKING_PROTO #include "fpu_proto.h" #endif #endif __ASSEMBLER__ #endif _FPU_EMU_H_