122 lines
		
	
	
	
		
			4.7 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			122 lines
		
	
	
	
		
			4.7 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*---------------------------------------------------------------------------+
 | ||
|  |  |  poly.h                                                                   | | ||
|  |  |                                                                           | | ||
|  |  |  Header file for the FPU-emu poly*.c source files.                        | | ||
|  |  |                                                                           | | ||
|  |  | Copyright (C) 1994,1999                                                   | | ||
|  |  |                       W. Metzenthen, 22 Parker St, Ormond, Vic 3163,      | | ||
|  |  |                       Australia.  E-mail   billm@melbpc.org.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, producing a 32 bit result.
 | ||
|  |    The answer is the ms word of the product. */ | ||
|  | /* Some versions of gcc make it difficult to stop eax from being clobbered.
 | ||
|  |    Merely specifying that it is used doesn't work... | ||
|  |  */ | ||
|  | static inline unsigned long mul_32_32(const unsigned long arg1, | ||
|  | 				      const unsigned long arg2) | ||
|  | { | ||
|  |   int retval; | ||
|  |   asm volatile ("mull %2; movl %%edx,%%eax" \ | ||
|  | 		:"=a" (retval) \ | ||
|  | 		:"0" (arg1), "g" (arg2) \ | ||
|  | 		:"dx"); | ||
|  |   return retval; | ||
|  | } | ||
|  | 
 | ||
|  | 
 | ||
|  | /* Add the 12 byte Xsig x2 to Xsig dest, with no checks for overflow. */ | ||
|  | static inline void add_Xsig_Xsig(Xsig *dest, const Xsig *x2) | ||
|  | { | ||
|  |   asm volatile ("movl %1,%%edi; movl %2,%%esi;\n" | ||
|  |                 "movl (%%esi),%%eax; addl %%eax,(%%edi);\n" | ||
|  |                 "movl 4(%%esi),%%eax; adcl %%eax,4(%%edi);\n" | ||
|  |                 "movl 8(%%esi),%%eax; adcl %%eax,8(%%edi);\n" | ||
|  |                  :"=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! */ | ||
|  | static inline void add_two_Xsig(Xsig *dest, const Xsig *x2, long int *exp) | ||
|  | { | ||
|  |   asm volatile ("movl %2,%%ecx; movl %3,%%esi;\n" | ||
|  |                 "movl (%%esi),%%eax; addl %%eax,(%%ecx);\n" | ||
|  |                 "movl 4(%%esi),%%eax; adcl %%eax,4(%%ecx);\n" | ||
|  |                 "movl 8(%%esi),%%eax; adcl %%eax,8(%%ecx);\n" | ||
|  |                 "jnc 0f;\n" | ||
|  | 		"rcrl 8(%%ecx); rcrl 4(%%ecx); rcrl (%%ecx)\n" | ||
|  |                 "movl %4,%%ecx; incl (%%ecx)\n" | ||
|  |                 "movl $1,%%eax; jmp 1f;\n" | ||
|  |                 "0: xorl %%eax,%%eax;\n" | ||
|  |                 "1:\n" | ||
|  | 		:"=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. */ | ||
|  | static inline void negate_Xsig(Xsig *x) | ||
|  | { | ||
|  |   asm volatile("movl %1,%%esi;\n" | ||
|  |                "xorl %%ecx,%%ecx;\n" | ||
|  |                "movl %%ecx,%%eax; subl (%%esi),%%eax; movl %%eax,(%%esi);\n" | ||
|  |                "movl %%ecx,%%eax; sbbl 4(%%esi),%%eax; movl %%eax,4(%%esi);\n" | ||
|  |                "movl %%ecx,%%eax; sbbl 8(%%esi),%%eax; movl %%eax,8(%%esi);\n" | ||
|  |                :"=g" (*x):"g" (x):"si","ax","cx"); | ||
|  | } | ||
|  | 
 | ||
|  | #endif /* _POLY_H */
 |