| /*---------------------------------------------------------------------------+ | |
| | fpu_emu.h | | |
| | | | |
| | Copyright (C) 1992,1993,1994,1997 | | |
| | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, | | |
| | Australia. E-mail billm@suburbia.net | | |
| | | | |
| +---------------------------------------------------------------------------*/ | |
| #ifndef _FPU_EMU_H_ | |
| #define _FPU_EMU_H_ | |
| /* | |
| * 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 __ASSEMBLY__ | |
| #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_WAY_UNDER Const(-0x6000) /* Below the smallest denormal, but | |
| still a 16 bit nr. */ | |
| #define EXP_Infinity EXP_OVER | |
| #define EXP_NaN EXP_OVER | |
| #define EXTENDED_Ebias Const(0x3fff) | |
| #define EXTENDED_Emin (-0x3ffe) /* smallest valid exponent */ | |
| #define SIGN_POS Const(0) | |
| #define SIGN_NEG Const(0x80) | |
| #define SIGN_Positive Const(0) | |
| #define SIGN_Negative Const(0x8000) | |
| /* Keep the order TAG_Valid, TAG_Zero, TW_Denormal */ | |
| /* 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_Unsupported Const(7) /* Not supported by an 80486 */ | |
| #define TAG_Valid Const(0) /* valid */ | |
| #define TAG_Zero Const(1) /* zero */ | |
| #define TAG_Special Const(2) /* De-normal, + or - infinity, | |
| or Not a Number */ | |
| #define TAG_Empty Const(3) /* empty */ | |
| #define TAG_Error Const(0x80) /* probably need to abort */ | |
| #define LOADED_DATA Const(10101) /* Special st() number to identify | |
| loaded data (not on stack). */ | |
| /* A few flags (must be >= 0x10). */ | |
| #define REV 0x10 | |
| #define DEST_RM 0x20 | |
| #define LOADED 0x40 | |
| #define FPU_Exception Const(0x80000000) /* Added to tag returns. */ | |
| #ifndef __ASSEMBLY__ | |
| #include "fpu_system.h" | |
| #include <uapi/asm/sigcontext.h> /* for struct _fpstate */ | |
| #include <asm/math_emu.h> | |
| #include <linux/linkage.h> | |
| /* | |
| #define RE_ENTRANT_CHECKING | |
| */ | |
| #ifdef RE_ENTRANT_CHECKING | |
| extern u_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 /* RE_ENTRANT_CHECKING */ | |
| #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 | |
| #define PREFIX_CS_ 1 | |
| #define PREFIX_DS_ 2 | |
| #define PREFIX_ES_ 3 | |
| #define PREFIX_FS_ 4 | |
| #define PREFIX_GS_ 5 | |
| #define PREFIX_SS_ 6 | |
| #define PREFIX_DEFAULT 7 | |
| struct address { | |
| unsigned int offset; | |
| unsigned int selector:16; | |
| unsigned int opcode:11; | |
| unsigned int empty:5; | |
| }; | |
| struct fpu__reg { | |
| unsigned sigl; | |
| unsigned sigh; | |
| short exp; | |
| }; | |
| typedef void (*FUNC) (void); | |
| typedef struct fpu__reg FPU_REG; | |
| typedef void (*FUNC_ST0) (FPU_REG *st0_ptr, u_char st0_tag); | |
| typedef struct { | |
| u_char address_size, operand_size, segment; | |
| } overrides; | |
| /* This structure is 32 bits: */ | |
| typedef struct { | |
| overrides override; | |
| u_char default_mode; | |
| } fpu_addr_modes; | |
| /* PROTECTED has a restricted meaning in the emulator; it is used | |
| to signal that the emulator needs to do special things to ensure | |
| that protection is respected in a segmented model. */ | |
| #define PROTECTED 4 | |
| #define SIXTEEN 1 /* We rely upon this being 1 (true) */ | |
| #define VM86 SIXTEEN | |
| #define PM16 (SIXTEEN | PROTECTED) | |
| #define SEG32 PROTECTED | |
| extern u_char const data_sizes_16[32]; | |
| #define register_base ((u_char *) registers ) | |
| #define fpu_register(x) ( * ((FPU_REG *)( register_base + 10 * (x & 7) )) ) | |
| #define st(x) ( * ((FPU_REG *)( register_base + 10 * ((top+x) & 7) )) ) | |
| #define STACK_OVERFLOW (FPU_stackoverflow(&st_new_ptr)) | |
| #define NOT_EMPTY(i) (!FPU_empty_i(i)) | |
| #define NOT_EMPTY_ST0 (st0_tag ^ TAG_Empty) | |
| #define poppop() { FPU_pop(); FPU_pop(); } | |
| /* push() does not affect the tags */ | |
| #define push() { top--; } | |
| #define signbyte(a) (((u_char *)(a))[9]) | |
| #define getsign(a) (signbyte(a) & 0x80) | |
| #define setsign(a,b) { if (b) signbyte(a) |= 0x80; else signbyte(a) &= 0x7f; } | |
| #define copysign(a,b) { if (getsign(a)) signbyte(b) |= 0x80; \ | |
| else signbyte(b) &= 0x7f; } | |
| #define changesign(a) { signbyte(a) ^= 0x80; } | |
| #define setpositive(a) { signbyte(a) &= 0x7f; } | |
| #define setnegative(a) { signbyte(a) |= 0x80; } | |
| #define signpositive(a) ( (signbyte(a) & 0x80) == 0 ) | |
| #define signnegative(a) (signbyte(a) & 0x80) | |
| static inline void reg_copy(FPU_REG const *x, FPU_REG *y) | |
| { | |
| *(short *)&(y->exp) = *(const short *)&(x->exp); | |
| *(long long *)&(y->sigl) = *(const long long *)&(x->sigl); | |
| } | |
| #define exponent(x) (((*(short *)&((x)->exp)) & 0x7fff) - EXTENDED_Ebias) | |
| #define setexponentpos(x,y) { (*(short *)&((x)->exp)) = \ | |
| ((y) + EXTENDED_Ebias) & 0x7fff; } | |
| #define exponent16(x) (*(short *)&((x)->exp)) | |
| #define setexponent16(x,y) { (*(short *)&((x)->exp)) = (y); } | |
| #define addexponent(x,y) { (*(short *)&((x)->exp)) += (y); } | |
| #define stdexp(x) { (*(short *)&((x)->exp)) += EXTENDED_Ebias; } | |
| #define isdenormal(ptr) (exponent(ptr) == EXP_BIAS+EXP_UNDER) | |
| #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 int FPU_normalize(FPU_REG *x); | |
| asmlinkage int FPU_normalize_nuo(FPU_REG *x); | |
| asmlinkage int FPU_u_sub(FPU_REG const *arg1, FPU_REG const *arg2, | |
| FPU_REG * answ, unsigned int control_w, u_char sign, | |
| int expa, int expb); | |
| asmlinkage int FPU_u_mul(FPU_REG const *arg1, FPU_REG const *arg2, | |
| FPU_REG * answ, unsigned int control_w, u_char sign, | |
| int expon); | |
| asmlinkage int FPU_u_div(FPU_REG const *arg1, FPU_REG const *arg2, | |
| FPU_REG * answ, unsigned int control_w, u_char sign); | |
| asmlinkage int FPU_u_add(FPU_REG const *arg1, FPU_REG const *arg2, | |
| FPU_REG * answ, unsigned int control_w, u_char sign, | |
| int expa, int expb); | |
| asmlinkage int wm_sqrt(FPU_REG *n, int dummy1, int dummy2, | |
| unsigned int control_w, u_char sign); | |
| asmlinkage unsigned FPU_shrx(void *l, unsigned x); | |
| asmlinkage unsigned FPU_shrxs(void *v, unsigned x); | |
| asmlinkage unsigned long FPU_div_small(unsigned long long *x, unsigned long y); | |
| asmlinkage int FPU_round(FPU_REG *arg, unsigned int extent, int dummy, | |
| unsigned int control_w, u_char sign); | |
| #ifndef MAKING_PROTO | |
| #include "fpu_proto.h" | |
| #endif | |
| #endif /* __ASSEMBLY__ */ | |
| #endif /* _FPU_EMU_H_ */ |