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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 | /*---------------------------------------------------------------------------+ | poly.h | | | | Header file for the FPU-emu poly*.c source files. | | | | Copyright (C) 1994 | | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, | | Australia. E-mail billm@vaxc.cc.monash.edu.au | | | | Declarations and definitions for functions operating on Xsig (12-byte | | extended-significand) quantities. | | | +---------------------------------------------------------------------------*/ #ifndef _POLY_H #define _POLY_H /* This 12-byte structure is used to improve the accuracy of computation of transcendental functions. Intended to be used to get results better than 8-byte computation allows. 9-byte would probably be sufficient. */ typedef struct { unsigned long lsw; unsigned long midw; unsigned long msw; } Xsig; asmlinkage void mul64(unsigned long long const *a, unsigned long long const *b, unsigned long long *result); asmlinkage void polynomial_Xsig(Xsig *, const unsigned long long *x, const unsigned long long terms[], const int n); asmlinkage void mul32_Xsig(Xsig *, const unsigned long mult); asmlinkage void mul64_Xsig(Xsig *, const unsigned long long *mult); asmlinkage void mul_Xsig_Xsig(Xsig *dest, const Xsig *mult); asmlinkage void shr_Xsig(Xsig *, const int n); asmlinkage int round_Xsig(Xsig *); asmlinkage int norm_Xsig(Xsig *); asmlinkage void div_Xsig(Xsig *x1, const Xsig *x2, const Xsig *dest); /* Macro to extract the most significant 32 bits from a long long */ #define LL_MSW(x) (((unsigned long *)&x)[1]) /* Macro to initialize an Xsig struct */ #define MK_XSIG(a,b,c) { c, b, a } /* Macro to access the 8 ms bytes of an Xsig as a long long */ #define XSIG_LL(x) (*(unsigned long long *)&x.midw) /* Need to run gcc with optimizations on to get these to actually be in-line. */ /* Multiply two fixed-point 32 bit numbers. */ extern inline void mul_32_32(const unsigned long arg1, const unsigned long arg2, unsigned long *out) { asm volatile ("movl %1,%%eax; mull %2; movl %%edx,%0" \ :"=g" (*out) \ :"g" (arg1), "g" (arg2) \ :"ax","dx"); } /* Add the 12 byte Xsig x2 to Xsig dest, with no checks for overflow. */ extern inline void add_Xsig_Xsig(Xsig *dest, const Xsig *x2) { asm volatile ("movl %1,%%edi; movl %2,%%esi; movl (%%esi),%%eax; addl %%eax,(%%edi); movl 4(%%esi),%%eax; adcl %%eax,4(%%edi); movl 8(%%esi),%%eax; adcl %%eax,8(%%edi);" :"=g" (*dest):"g" (dest), "g" (x2) :"ax","si","di"); } /* Add the 12 byte Xsig x2 to Xsig dest, adjust exp if overflow occurs. */ /* Note: the constraints in the asm statement didn't always work properly with gcc 2.5.8. Changing from using edi to using ecx got around the problem, but keep fingers crossed! */ extern inline int add_two_Xsig(Xsig *dest, const Xsig *x2, long int *exp) { asm volatile ("movl %2,%%ecx; movl %3,%%esi; movl (%%esi),%%eax; addl %%eax,(%%ecx); movl 4(%%esi),%%eax; adcl %%eax,4(%%ecx); movl 8(%%esi),%%eax; adcl %%eax,8(%%ecx); jnc 0f; rcrl 8(%%ecx); rcrl 4(%%ecx); rcrl (%%ecx) movl %4,%%ecx; incl (%%ecx) movl $1,%%eax; jmp 1f; 0: xorl %%eax,%%eax; 1:" :"=g" (*exp), "=g" (*dest) :"g" (dest), "g" (x2), "g" (exp) :"cx","si","ax"); } /* Negate (subtract from 1.0) the 12 byte Xsig */ /* This is faster in a loop on my 386 than using the "neg" instruction. */ extern inline void negate_Xsig(Xsig *x) { asm volatile("movl %1,%%esi; " "xorl %%ecx,%%ecx; " "movl %%ecx,%%eax; subl (%%esi),%%eax; movl %%eax,(%%esi); " "movl %%ecx,%%eax; sbbl 4(%%esi),%%eax; movl %%eax,4(%%esi); " "movl %%ecx,%%eax; sbbl 8(%%esi),%%eax; movl %%eax,8(%%esi); " :"=g" (*x):"g" (x):"si","ax","cx"); } #endif _POLY_H |