0,0 → 1,159 |
/* |
* Copyright (C) 2005 Josef Cejka |
* All rights reserved. |
* |
* Redistribution and use in source and binary forms, with or without |
* modification, are permitted provided that the following conditions |
* are met: |
* |
* - Redistributions of source code must retain the above copyright |
* notice, this list of conditions and the following disclaimer. |
* - Redistributions in binary form must reproduce the above copyright |
* notice, this list of conditions and the following disclaimer in the |
* documentation and/or other materials provided with the distribution. |
* - The name of the author may not be used to endorse or promote products |
* derived from this software without specific prior written permission. |
* |
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
*/ |
|
#include <arch/fmath.h> |
#include <print.h> |
|
//TODO: |
#define FMATH_MANTISA_MASK ( 0x000fffffffffffffLL ) |
|
int fmath_is_negative(double num) |
{ //TODO: |
/* fmath_ld_union_t fmath_ld_union; |
fmath_ld_union.bf = num; |
return ((fmath_ld_union.ldd[7])&0x80)==0x80; //first bit is sign, IA32 is little endian -> 8th byte |
*/ |
return 0; |
} |
|
signed short fmath_get_binary_exponent(double num) |
{ //TODO: |
/* fmath_ld_union_t fmath_ld_union; |
fmath_ld_union.bf = num; |
return (signed short)((((fmath_ld_union.ldd[7])&0x7f)<<4) + (((fmath_ld_union.ldd[6])&0xf0)>>4)) -FMATH_EXPONENT_BIAS; // exponent is 11 bits lenght, so sevent bits is in 8th byte and 4 bits in 7th |
*/ |
return 0; |
} |
|
double fmath_get_decimal_exponent(double num) |
{ //TODO: |
double value; |
// log10(2)*log2(x) => log10(x) |
/* __asm__ __volatile__ ( \ |
"fldlg2 #load log10(2) \n\t" \ |
"fxch %%st(1) \n\t" \ |
"fyl2x #count st(0)*log2(st(1))->st(1); pop st(0) \n\t" \ |
: "=t" (value) : "0"(num) ); |
*/ return value; |
|
} |
|
__u64 fmath_get_binary_mantisa(double num) |
{ //TODO: |
/* union { __u64 _u; double _d;} un = { _d : num }; |
un._u=un._u &(FMATH_MANTISA_MASK); // mask 52 bits of mantisa |
return un._u; |
*/ |
return 0; |
} |
|
double fmath_fint(double num, double *intp) |
{ //TODO: |
/* fmath_ld_union_t fmath_ld_union_num; |
fmath_ld_union_t fmath_ld_union_int; |
signed short exp; |
__u64 mask,mantisa; |
int i; |
|
exp=fmath_get_binary_exponent(num); |
|
if (exp<0) { |
*intp = 0.0; |
*intp = fmath_set_sign(0.0L,fmath_is_negative(num)); |
return num; |
} |
|
|
if (exp>51) { |
*intp=num; |
num=0.0; |
num= fmath_set_sign(0.0L,fmath_is_negative(*intp)); |
return num; |
} |
|
fmath_ld_union_num.bf = num; |
|
mask = FMATH_MANTISA_MASK>>exp; |
//mantisa = (fmath_get-binary_mantisa(num))&(~mask); |
|
for (i=0;i<7;i++) { |
// Ugly construction for obtain sign, exponent and integer part from num |
fmath_ld_union_int.ldd[i]=fmath_ld_union_num.ldd[i]&(((~mask)>>(i*8))&0xff); |
} |
|
fmath_ld_union_int.ldd[6]|=((fmath_ld_union_num.ldd[6])&(0xf0)); |
fmath_ld_union_int.ldd[7]=fmath_ld_union_num.ldd[7]; |
|
*intp=fmath_ld_union_int.bf; |
return fmath_ld_union_num.bf-fmath_ld_union_int.bf; |
*/ |
|
return 0.0; |
}; |
|
double fmath_set_sign(double num,__u8 sign) |
{ //TODO: |
/* fmath_ld_union_t fmath_ld_union; |
fmath_ld_union.bf = num; |
fmath_ld_union.ldd[7]=((fmath_ld_union.ldd[7])&0x7f)|(sign<<7); // change 64th bit (IA32 is a little endian) |
return fmath_ld_union.bf; |
*/ return 1.0 |
} |
|
double fmath_abs(double num) |
{ //TODO: |
/* |
return fmath_set_sign(num,0); |
*/ |
return 1.0; |
} |
|
double fmath_dpow(double base, double exponent) |
{ //TODO: |
/* double value=1.0; |
if (base<=0.0) return base; |
|
//2^(x*log2(10)) = 2^y = 10^x |
|
__asm__ __volatile__ ( \ |
"fyl2x # ST(1):=ST(1)*log2(ST(0)), pop st(0) \n\t " \ |
"fld %%st(0) \n\t" \ |
"frndint \n\t" \ |
"fxch %%st(1) \n\t" \ |
"fsub %%st(1),%%st(0) \n\t" \ |
"f2xm1 # ST := 2^ST -1\n\t" \ |
"fld1 \n\t" \ |
"faddp %%st(0),%%st(1) \n\t" \ |
"fscale #ST:=ST*2^(ST(1))\n\t" \ |
"fstp %%st(1) \n\t" \ |
"" : "=t" (value) : "0" (base), "u" (exponent) ); |
return value; |
*/ |
return 1.0; |
} |
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