/*[0,pi/4)に簡約*/
uint32_t fsin(uint32_t f){
if(fcmp(f,0) == 0)
return fneg(fsin(f - (1 << 31)));
if(fcmp(f,0x40c90fda) == 2)
return fsin(fadd(f,0xc0c90fda));
if(fcmp(f,MYPI) == 0){
if(fcmp(f,MYPI2) == 0){
if(fcmp(f,MYPI4) == 0)
return kernel_sin(f);
else
return kernel_cos(fadd(MYPI2,fneg(f)));
}else{
if(fcmp(f,fadd(MYPI4,MYPI2)) == 0)
kernel_cos(fadd(f,fneg(MYPI2)));
else
kernel_sin(fadd(MYPI,fneg(f)));
}
}else{
f = fadd(f,fneg(MYPI));
if(fcmp(f,MYPI2) == 0){
if(fcmp(f,MYPI4) == 0)
return fneg(kernel_sin(f));
else
return fneg(kernel_cos(fadd(MYPI2,fneg(f))));
}else{
if(fcmp(f,fadd(MYPI4,MYPI2)) == 0)
fneg(kernel_cos(fadd(f,fneg(MYPI2))));
else
fneg(kernel_sin(fadd(MYPI,fneg(f))));
}
}
}
float mysin(float a) {
int flag = (a<0.0)?1:0;
a = fabsf(a);
a = reduction_2pi(a);
if (a>=(float)M_PI) {
a -= (float)M_PI;
flag ^= 1;
}
if (a>=(float)M_PI/2.0f) a = (float)M_PI - a;
if (a<=(float)M_PI/4.0f) {
return kernel_sin(a, flag);
} else {
a = (float)M_PI/2.0f - a;
return kernel_cos(a, flag);
}
}