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diff --git a/arch/x86/math-emu/fpu_emu.h b/arch/x86/math-emu/fpu_emu.h
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+++ b/arch/x86/math-emu/fpu_emu.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+/*---------------------------------------------------------------------------+
+ | 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) != 0) 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)) = (u16)(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_ */