sdrangel/plugins/channelrx/demoddatv/ldpctool/algorithms.h

417 lines
8.8 KiB
C++

/*
SIMD-ified LDPC algorithms
Copyright 2018 Ahmet Inan <xdsopl@gmail.com>
*/
#ifndef ALGORITHMS_HH
#define ALGORITHMS_HH
#include "generic.h"
#include "exclusive_reduce.h"
namespace ldpctool {
template <typename VALUE, int WIDTH>
struct SelfCorrectedUpdate<SIMD<VALUE, WIDTH>>
{
typedef SIMD<VALUE, WIDTH> TYPE;
static void update(TYPE *a, TYPE b)
{
*a = vreinterpret<TYPE>(vand(vmask(b), vorr(vceqz(*a), veor(vcgtz(*a), vcltz(b)))));
}
};
template <typename VALUE, int WIDTH, typename UPDATE>
struct MinSumAlgorithm<SIMD<VALUE, WIDTH>, UPDATE>
{
typedef SIMD<VALUE, WIDTH> TYPE;
static TYPE zero()
{
return vzero<TYPE>();
}
static TYPE one()
{
return vdup<TYPE>(1);
}
static TYPE min(TYPE a, TYPE b)
{
return vmin(a, b);
}
static TYPE sign(TYPE a, TYPE b)
{
return vsign(a, b);
}
static void finalp(TYPE *links, int cnt)
{
TYPE mags[cnt], mins[cnt];
for (int i = 0; i < cnt; ++i)
mags[i] = vabs(links[i]);
CODE::exclusive_reduce(mags, mins, cnt, min);
TYPE signs[cnt];
CODE::exclusive_reduce(links, signs, cnt, sign);
for (int i = 0; i < cnt; ++i)
links[i] = sign(mins[i], signs[i]);
}
static TYPE add(TYPE a, TYPE b)
{
return vadd(a, b);
}
static TYPE sub(TYPE a, TYPE b)
{
return vsub(a, b);
}
static bool bad(TYPE v, int blocks)
{
auto tmp = vcgtz(v);
for (int i = 0; i < blocks; ++i)
if (!tmp.v[i])
return true;
return false;
}
static void update(TYPE *a, TYPE b)
{
UPDATE::update(a, b);
}
};
template <int WIDTH, typename UPDATE>
struct MinSumAlgorithm<SIMD<int8_t, WIDTH>, UPDATE>
{
typedef int8_t VALUE;
typedef SIMD<VALUE, WIDTH> TYPE;
static TYPE zero()
{
return vzero<TYPE>();
}
static TYPE one()
{
return vdup<TYPE>(1);
}
static TYPE sign(TYPE a, TYPE b)
{
return vsign(a, b);
}
static TYPE eor(TYPE a, TYPE b)
{
return vreinterpret<TYPE>(veor(vmask(a), vmask(b)));
}
static TYPE orr(TYPE a, TYPE b)
{
return vreinterpret<TYPE>(vorr(vmask(a), vmask(b)));
}
static TYPE other(TYPE a, TYPE b, TYPE c)
{
return vreinterpret<TYPE>(vbsl(vceq(a, b), vmask(c), vmask(b)));
}
static void finalp(TYPE *links, int cnt)
{
TYPE mags[cnt];
for (int i = 0; i < cnt; ++i)
mags[i] = vqabs(links[i]);
TYPE mins[2];
mins[0] = vmin(mags[0], mags[1]);
mins[1] = vmax(mags[0], mags[1]);
for (int i = 2; i < cnt; ++i) {
mins[1] = vmin(mins[1], vmax(mins[0], mags[i]));
mins[0] = vmin(mins[0], mags[i]);
}
TYPE signs = links[0];
for (int i = 1; i < cnt; ++i)
signs = eor(signs, links[i]);
for (int i = 0; i < cnt; ++i)
links[i] = sign(other(mags[i], mins[0], mins[1]), orr(eor(signs, links[i]), vdup<TYPE>(127)));
}
static TYPE add(TYPE a, TYPE b)
{
return vqadd(a, b);
}
static TYPE sub(TYPE a, TYPE b)
{
return vqsub(a, b);
}
static bool bad(TYPE v, int blocks)
{
auto tmp = vcgtz(v);
for (int i = 0; i < blocks; ++i)
if (!tmp.v[i])
return true;
return false;
}
static void update(TYPE *a, TYPE b)
{
UPDATE::update(a, vmin(vmax(b, vdup<TYPE>(-32)), vdup<TYPE>(31)));
}
};
template <typename VALUE, int WIDTH, typename UPDATE, int FACTOR>
struct OffsetMinSumAlgorithm<SIMD<VALUE, WIDTH>, UPDATE, FACTOR>
{
typedef SIMD<VALUE, WIDTH> TYPE;
static TYPE zero()
{
return vzero<TYPE>();
}
static TYPE one()
{
return vdup<TYPE>(1);
}
static TYPE min(TYPE a, TYPE b)
{
return vmin(a, b);
}
static TYPE sign(TYPE a, TYPE b)
{
return vsign(a, b);
}
static void finalp(TYPE *links, int cnt)
{
TYPE beta = vdup<TYPE>(0.5 * FACTOR);
TYPE mags[cnt], mins[cnt];
for (int i = 0; i < cnt; ++i)
mags[i] = vmax(vsub(vabs(links[i]), beta), vzero<TYPE>());
CODE::exclusive_reduce(mags, mins, cnt, min);
TYPE signs[cnt];
CODE::exclusive_reduce(links, signs, cnt, sign);
for (int i = 0; i < cnt; ++i)
links[i] = sign(mins[i], signs[i]);
}
static TYPE add(TYPE a, TYPE b)
{
return vadd(a, b);
}
static TYPE sub(TYPE a, TYPE b)
{
return vsub(a, b);
}
static bool bad(TYPE v, int blocks)
{
auto tmp = vcgtz(v);
for (int i = 0; i < blocks; ++i)
if (!tmp.v[i])
return true;
return false;
}
static void update(TYPE *a, TYPE b)
{
UPDATE::update(a, b);
}
};
template <int WIDTH, typename UPDATE, int FACTOR>
struct OffsetMinSumAlgorithm<SIMD<int8_t, WIDTH>, UPDATE, FACTOR>
{
typedef int8_t VALUE;
typedef SIMD<VALUE, WIDTH> TYPE;
static TYPE zero()
{
return vzero<TYPE>();
}
static TYPE one()
{
return vdup<TYPE>(1);
}
static TYPE sign(TYPE a, TYPE b)
{
return vsign(a, b);
}
static TYPE eor(TYPE a, TYPE b)
{
return vreinterpret<TYPE>(veor(vmask(a), vmask(b)));
}
static TYPE orr(TYPE a, TYPE b)
{
return vreinterpret<TYPE>(vorr(vmask(a), vmask(b)));
}
static TYPE other(TYPE a, TYPE b, TYPE c)
{
return vreinterpret<TYPE>(vbsl(vceq(a, b), vmask(c), vmask(b)));
}
static void finalp(TYPE *links, int cnt)
{
auto beta = vunsigned(vdup<TYPE>(std::nearbyint(0.5 * FACTOR)));
TYPE mags[cnt];
for (int i = 0; i < cnt; ++i)
mags[i] = vsigned(vqsub(vunsigned(vqabs(links[i])), beta));
TYPE mins[2];
mins[0] = vmin(mags[0], mags[1]);
mins[1] = vmax(mags[0], mags[1]);
for (int i = 2; i < cnt; ++i) {
mins[1] = vmin(mins[1], vmax(mins[0], mags[i]));
mins[0] = vmin(mins[0], mags[i]);
}
TYPE signs = links[0];
for (int i = 1; i < cnt; ++i)
signs = eor(signs, links[i]);
for (int i = 0; i < cnt; ++i)
links[i] = sign(other(mags[i], mins[0], mins[1]), orr(eor(signs, links[i]), vdup<TYPE>(127)));
}
static TYPE add(TYPE a, TYPE b)
{
return vqadd(a, b);
}
static TYPE sub(TYPE a, TYPE b)
{
return vqsub(a, b);
}
static bool bad(TYPE v, int blocks)
{
auto tmp = vcgtz(v);
for (int i = 0; i < blocks; ++i)
if (!tmp.v[i])
return true;
return false;
}
static void update(TYPE *a, TYPE b)
{
UPDATE::update(a, vmin(vmax(b, vdup<TYPE>(-32)), vdup<TYPE>(31)));
}
};
template <typename VALUE, int WIDTH, typename UPDATE, int FACTOR>
struct MinSumCAlgorithm<SIMD<VALUE, WIDTH>, UPDATE, FACTOR>
{
typedef SIMD<VALUE, WIDTH> TYPE;
static TYPE zero()
{
return vzero<TYPE>();
}
static TYPE one()
{
return vdup<TYPE>(1);
}
static TYPE sign(TYPE a, TYPE b)
{
return vsign(a, b);
}
static TYPE correction_factor(TYPE a, TYPE b)
{
TYPE apb = vabs(vadd(a, b));
TYPE apb2 = vadd(apb, apb);
TYPE amb = vabs(vsub(a, b));
TYPE amb2 = vadd(amb, amb);
TYPE factor2 = vdup<TYPE>(FACTOR * 2);
auto pc = vmask(vdup<TYPE>(VALUE(FACTOR) / VALUE(2)));
auto nc = vmask(vdup<TYPE>(-VALUE(FACTOR) / VALUE(2)));
pc = vand(pc, vand(vcgt(factor2, apb), vcgt(amb, apb2)));
nc = vand(nc, vand(vcgt(factor2, amb), vcgt(apb, amb2)));
return vreinterpret<TYPE>(vorr(pc, nc));
}
static TYPE minc(TYPE a, TYPE b)
{
TYPE m = vmin(vabs(a), vabs(b));
TYPE x = vsign(vsign(m, a), b);
x = vadd(x, correction_factor(a, b));
return x;
}
static void finalp(TYPE *links, int cnt)
{
TYPE tmp[cnt];
CODE::exclusive_reduce(links, tmp, cnt, minc);
for (int i = 0; i < cnt; ++i)
links[i] = tmp[i];
}
static TYPE add(TYPE a, TYPE b)
{
return vadd(a, b);
}
static TYPE sub(TYPE a, TYPE b)
{
return vsub(a, b);
}
static bool bad(TYPE v, int blocks)
{
auto tmp = vcgtz(v);
for (int i = 0; i < blocks; ++i)
if (!tmp.v[i])
return true;
return false;
}
static void update(TYPE *a, TYPE b)
{
UPDATE::update(a, b);
}
};
template <int WIDTH, typename UPDATE, int FACTOR>
struct MinSumCAlgorithm<SIMD<int8_t, WIDTH>, UPDATE, FACTOR>
{
typedef int8_t VALUE;
typedef SIMD<VALUE, WIDTH> TYPE;
static TYPE zero()
{
return vzero<TYPE>();
}
static TYPE one()
{
return vdup<TYPE>(1);
}
static TYPE sign(TYPE a, TYPE b)
{
return vsign(a, b);
}
static TYPE correction_factor(TYPE a, TYPE b)
{
TYPE apb = vqabs(vqadd(a, b));
TYPE apb2 = vqadd(apb, apb);
TYPE amb = vqabs(vqsub(a, b));
TYPE amb2 = vqadd(amb, amb);
TYPE factor2 = vdup<TYPE>(FACTOR * 2);
auto pc = vmask(vdup<TYPE>(VALUE(FACTOR) / VALUE(2)));
auto nc = vmask(vdup<TYPE>(-VALUE(FACTOR) / VALUE(2)));
pc = vand(pc, vand(vcgt(factor2, apb), vcgt(amb, apb2)));
nc = vand(nc, vand(vcgt(factor2, amb), vcgt(apb, amb2)));
return vreinterpret<TYPE>(vorr(pc, nc));
}
static TYPE minc(TYPE a, TYPE b)
{
TYPE m = vmin(vqabs(a), vqabs(b));
TYPE x = vsign(vsign(m, a), b);
x = vqadd(x, correction_factor(a, b));
return x;
}
static void finalp(TYPE *links, int cnt)
{
TYPE *tmp = new TYPE[cnt];
CODE::exclusive_reduce(links, tmp, cnt, minc);
for (int i = 0; i < cnt; ++i)
links[i] = tmp[i];
delete[] tmp;
}
static TYPE add(TYPE a, TYPE b)
{
return vqadd(a, b);
}
static TYPE sub(TYPE a, TYPE b)
{
return vqsub(a, b);
}
static bool bad(TYPE v, int blocks)
{
auto tmp = vcgtz(v);
for (int i = 0; i < blocks; ++i)
if (!tmp.v[i])
return true;
return false;
}
static void update(TYPE *a, TYPE b)
{
UPDATE::update(a, vmin(vmax(b, vdup<TYPE>(-32)), vdup<TYPE>(31)));
}
};
} // namespace ldpctool
#endif