Files
eigen/Eigen/src/Core/arch/AltiVec/PacketMath.h
Gael Guennebaud 17860e578c add SSE2 versions of sin, cos, log, exp using code from Julien
Pommier. They are for float only, and they return exactly the same
result as the standard versions in about 90% of the cases. Otherwise the max error
is below 1e-7. However, for very large values (>1e3) the accuracy of sin and cos
slighlty decrease. They are about 3 or 4 times faster than 4 calls to their respective
standard versions. So, is it ok to enable them by default in their respective functors ?
2009-03-25 12:26:13 +00:00

434 lines
14 KiB
C++

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra. Eigen itself is part of the KDE project.
//
// Copyright (C) 2008 Konstantinos Margaritis <markos@codex.gr>
//
// Eigen is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 3 of the License, or (at your option) any later version.
//
// Alternatively, you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 2 of
// the License, or (at your option) any later version.
//
// Eigen is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License or the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License and a copy of the GNU General Public License along with
// Eigen. If not, see <http://www.gnu.org/licenses/>.
#ifndef EIGEN_PACKET_MATH_ALTIVEC_H
#define EIGEN_PACKET_MATH_ALTIVEC_H
#ifndef EIGEN_CACHEFRIENDLY_PRODUCT_THRESHOLD
#define EIGEN_CACHEFRIENDLY_PRODUCT_THRESHOLD 4
#endif
typedef __vector float v4f;
typedef __vector int v4i;
typedef __vector unsigned int v4ui;
typedef __vector __bool int v4bi;
// We don't want to write the same code all the time, but we need to reuse the constants
// and it doesn't really work to declare them global, so we define macros instead
#define USE_CONST_v0i const v4i v0i = vec_splat_s32(0)
#define USE_CONST_v1i const v4i v1i = vec_splat_s32(1)
#define USE_CONST_v16i_ const v4i v16i_ = vec_splat_s32(-16)
#define USE_CONST_v0f USE_CONST_v0i; const v4f v0f = (v4f) v0i
#define USE_CONST_v1f USE_CONST_v1i; const v4f v1f = vec_ctf(v1i, 0)
#define USE_CONST_v1i_ const v4ui v1i_ = vec_splat_u32(-1)
#define USE_CONST_v0f_ USE_CONST_v1i_; const v4f v0f_ = (v4f) vec_sl(v1i_, v1i_)
template<> struct ei_packet_traits<float> : ei_default_packet_traits
{ typedef v4f type; enum {size=4}; };
template<> struct ei_packet_traits<int> : ei_default_packet_traits
{ typedef v4i type; enum {size=4}; };
template<> struct ei_unpacket_traits<v4f> { typedef float type; enum {size=4}; };
template<> struct ei_unpacket_traits<v4i> { typedef int type; enum {size=4}; };
inline std::ostream & operator <<(std::ostream & s, const v4f & v)
{
union {
v4f v;
float n[4];
} vt;
vt.v = v;
s << vt.n[0] << ", " << vt.n[1] << ", " << vt.n[2] << ", " << vt.n[3];
return s;
}
inline std::ostream & operator <<(std::ostream & s, const v4i & v)
{
union {
v4i v;
int n[4];
} vt;
vt.v = v;
s << vt.n[0] << ", " << vt.n[1] << ", " << vt.n[2] << ", " << vt.n[3];
return s;
}
inline std::ostream & operator <<(std::ostream & s, const v4ui & v)
{
union {
v4ui v;
unsigned int n[4];
} vt;
vt.v = v;
s << vt.n[0] << ", " << vt.n[1] << ", " << vt.n[2] << ", " << vt.n[3];
return s;
}
inline std::ostream & operator <<(std::ostream & s, const v4bi & v)
{
union {
__vector __bool int v;
unsigned int n[4];
} vt;
vt.v = v;
s << vt.n[0] << ", " << vt.n[1] << ", " << vt.n[2] << ", " << vt.n[3];
return s;
}
template<> inline v4f ei_padd(const v4f& a, const v4f& b) { return vec_add(a,b); }
template<> inline v4i ei_padd(const v4i& a, const v4i& b) { return vec_add(a,b); }
template<> inline v4f ei_psub(const v4f& a, const v4f& b) { return vec_sub(a,b); }
template<> inline v4i ei_psub(const v4i& a, const v4i& b) { return vec_sub(a,b); }
template<> EIGEN_STRONG_INLINE v4f ei_pnegate(const v4f& a)
{
v4i mask = {0x80000000, 0x80000000, 0x80000000, 0x80000000};
return vec_xor(a,(v4f) mask);
}
template<> EIGEN_STRONG_INLINE v4i ei_pnegate(const v4i& a)
{
USE_CONST_v0i;
return ei_psub(v0i, a);
}
template<> inline v4f ei_pmul(const v4f& a, const v4f& b) { USE_CONST_v0f; return vec_madd(a,b, v0f); }
template<> inline v4i ei_pmul(const v4i& a, const v4i& b)
{
// Detailed in: http://freevec.org/content/32bit_signed_integer_multiplication_altivec
//Set up constants, variables
v4i a1, b1, bswap, low_prod, high_prod, prod, prod_, v1sel;
USE_CONST_v0i;
USE_CONST_v1i;
USE_CONST_v16i_;
// Get the absolute values
a1 = vec_abs(a);
b1 = vec_abs(b);
// Get the signs using xor
v4bi sgn = (v4bi) vec_cmplt(vec_xor(a, b), v0i);
// Do the multiplication for the asbolute values.
bswap = (v4i) vec_rl((v4ui) b1, (v4ui) v16i_ );
low_prod = vec_mulo((__vector short)a1, (__vector short)b1);
high_prod = vec_msum((__vector short)a1, (__vector short)bswap, v0i);
high_prod = (v4i) vec_sl((v4ui) high_prod, (v4ui) v16i_);
prod = vec_add( low_prod, high_prod );
// NOR the product and select only the negative elements according to the sign mask
prod_ = vec_nor(prod, prod);
prod_ = vec_sel(v0i, prod_, sgn);
// Add 1 to the result to get the negative numbers
v1sel = vec_sel(v0i, v1i, sgn);
prod_ = vec_add(prod_, v1sel);
// Merge the results back to the final vector.
prod = vec_sel(prod, prod_, sgn);
return prod;
}
template<> inline v4f ei_pdiv(const v4f& a, const v4f& b) {
v4f t, y_0, y_1, res;
USE_CONST_v0f;
USE_CONST_v1f;
// Altivec does not offer a divide instruction, we have to do a reciprocal approximation
y_0 = vec_re(b);
// Do one Newton-Raphson iteration to get the needed accuracy
t = vec_nmsub(y_0, b, v1f);
y_1 = vec_madd(y_0, t, y_0);
res = vec_madd(a, y_1, v0f);
return res;
}
template<> inline v4f ei_pmadd(const v4f& a, const v4f& b, const v4f& c) { return vec_madd(a, b, c); }
template<> inline v4f ei_pmin(const v4f& a, const v4f& b) { return vec_min(a,b); }
template<> inline v4i ei_pmin(const v4i& a, const v4i& b) { return vec_min(a,b); }
template<> inline v4f ei_pmax(const v4f& a, const v4f& b) { return vec_max(a,b); }
template<> inline v4i ei_pmax(const v4i& a, const v4i& b) { return vec_max(a,b); }
template<> EIGEN_STRONG_INLINE v4f ei_pabs(const v4f& a) { return vec_abs(a); }
template<> EIGEN_STRONG_INLINE v4i ei_pabs(const v4i& a) { return vec_abs(a); }
template<> inline v4f ei_pload(const float* from) { return vec_ld(0, from); }
template<> inline v4i ei_pload(const int* from) { return vec_ld(0, from); }
template<> inline v4f ei_ploadu(const float* from)
{
// Taken from http://developer.apple.com/hardwaredrivers/ve/alignment.html
__vector unsigned char MSQ, LSQ;
__vector unsigned char mask;
MSQ = vec_ld(0, (unsigned char *)from); // most significant quadword
LSQ = vec_ld(15, (unsigned char *)from); // least significant quadword
mask = vec_lvsl(0, from); // create the permute mask
return (v4f) vec_perm(MSQ, LSQ, mask); // align the data
}
template<> inline v4i ei_ploadu(const int* from)
{
// Taken from http://developer.apple.com/hardwaredrivers/ve/alignment.html
__vector unsigned char MSQ, LSQ;
__vector unsigned char mask;
MSQ = vec_ld(0, (unsigned char *)from); // most significant quadword
LSQ = vec_ld(15, (unsigned char *)from); // least significant quadword
mask = vec_lvsl(0, from); // create the permute mask
return (v4i) vec_perm(MSQ, LSQ, mask); // align the data
}
template<> inline v4f ei_pset1(const float& from)
{
// Taken from http://developer.apple.com/hardwaredrivers/ve/alignment.html
float __attribute__(aligned(16)) af[4];
af[0] = from;
v4f vc = vec_ld(0, af);
vc = vec_splat(vc, 0);
return vc;
}
template<> inline v4i ei_pset1(const int& from)
{
int __attribute__(aligned(16)) ai[4];
ai[0] = from;
v4i vc = vec_ld(0, ai);
vc = vec_splat(vc, 0);
return vc;
}
template<> inline void ei_pstore(float* to, const v4f& from) { vec_st(from, 0, to); }
template<> inline void ei_pstore(int* to, const v4i& from) { vec_st(from, 0, to); }
template<> inline void ei_pstoreu(float* to, const v4f& from)
{
// Taken from http://developer.apple.com/hardwaredrivers/ve/alignment.html
// Warning: not thread safe!
__vector unsigned char MSQ, LSQ, edges;
__vector unsigned char edgeAlign, align;
MSQ = vec_ld(0, (unsigned char *)to); // most significant quadword
LSQ = vec_ld(15, (unsigned char *)to); // least significant quadword
edgeAlign = vec_lvsl(0, to); // permute map to extract edges
edges=vec_perm(LSQ,MSQ,edgeAlign); // extract the edges
align = vec_lvsr( 0, to ); // permute map to misalign data
MSQ = vec_perm(edges,(__vector unsigned char)from,align); // misalign the data (MSQ)
LSQ = vec_perm((__vector unsigned char)from,edges,align); // misalign the data (LSQ)
vec_st( LSQ, 15, (unsigned char *)to ); // Store the LSQ part first
vec_st( MSQ, 0, (unsigned char *)to ); // Store the MSQ part
}
template<> inline void ei_pstoreu(int* to , const v4i& from )
{
// Taken from http://developer.apple.com/hardwaredrivers/ve/alignment.html
// Warning: not thread safe!
__vector unsigned char MSQ, LSQ, edges;
__vector unsigned char edgeAlign, align;
MSQ = vec_ld(0, (unsigned char *)to); // most significant quadword
LSQ = vec_ld(15, (unsigned char *)to); // least significant quadword
edgeAlign = vec_lvsl(0, to); // permute map to extract edges
edges=vec_perm(LSQ,MSQ,edgeAlign); // extract the edges
align = vec_lvsr( 0, to ); // permute map to misalign data
MSQ = vec_perm(edges,(__vector unsigned char)from,align); // misalign the data (MSQ)
LSQ = vec_perm((__vector unsigned char)from,edges,align); // misalign the data (LSQ)
vec_st( LSQ, 15, (unsigned char *)to ); // Store the LSQ part first
vec_st( MSQ, 0, (unsigned char *)to ); // Store the MSQ part
}
template<> inline float ei_pfirst(const v4f& a)
{
float EIGEN_ALIGN_128 af[4];
vec_st(a, 0, af);
return af[0];
}
template<> inline int ei_pfirst(const v4i& a)
{
int EIGEN_ALIGN_128 ai[4];
vec_st(a, 0, ai);
return ai[0];
}
template<> EIGEN_STRONG_INLINE v4f ei_preverse(const v4f& a)
{
static const __vector unsigned char reverse_mask =
{12,13,14,15, 8,9,10,11, 4,5,6,7, 0,1,2,3};
return (v4f)vec_perm((__vector unsigned char)a,(__vector unsigned char)a,reverse_mask);
}
template<> EIGEN_STRONG_INLINE v4i ei_preverse(const v4i& a)
{
static const __vector unsigned char __attribute__(aligned(16)) reverse_mask =
{12,13,14,15, 8,9,10,11, 4,5,6,7, 0,1,2,3};
return (v4i)vec_perm((__vector unsigned char)a,(__vector unsigned char)a,reverse_mask);
}
inline v4f ei_preduxp(const v4f* vecs)
{
v4f v[4], sum[4];
// It's easier and faster to transpose then add as columns
// Check: http://www.freevec.org/function/matrix_4x4_transpose_floats for explanation
// Do the transpose, first set of moves
v[0] = vec_mergeh(vecs[0], vecs[2]);
v[1] = vec_mergel(vecs[0], vecs[2]);
v[2] = vec_mergeh(vecs[1], vecs[3]);
v[3] = vec_mergel(vecs[1], vecs[3]);
// Get the resulting vectors
sum[0] = vec_mergeh(v[0], v[2]);
sum[1] = vec_mergel(v[0], v[2]);
sum[2] = vec_mergeh(v[1], v[3]);
sum[3] = vec_mergel(v[1], v[3]);
// Now do the summation:
// Lines 0+1
sum[0] = vec_add(sum[0], sum[1]);
// Lines 2+3
sum[1] = vec_add(sum[2], sum[3]);
// Add the results
sum[0] = vec_add(sum[0], sum[1]);
return sum[0];
}
inline v4i ei_preduxp(const v4i* vecs)
{
v4i v[4], sum[4];
// It's easier and faster to transpose then add as columns
// Check: http://www.freevec.org/function/matrix_4x4_transpose_floats for explanation
// Do the transpose, first set of moves
v[0] = vec_mergeh(vecs[0], vecs[2]);
v[1] = vec_mergel(vecs[0], vecs[2]);
v[2] = vec_mergeh(vecs[1], vecs[3]);
v[3] = vec_mergel(vecs[1], vecs[3]);
// Get the resulting vectors
sum[0] = vec_mergeh(v[0], v[2]);
sum[1] = vec_mergel(v[0], v[2]);
sum[2] = vec_mergeh(v[1], v[3]);
sum[3] = vec_mergel(v[1], v[3]);
// Now do the summation:
// Lines 0+1
sum[0] = vec_add(sum[0], sum[1]);
// Lines 2+3
sum[1] = vec_add(sum[2], sum[3]);
// Add the results
sum[0] = vec_add(sum[0], sum[1]);
return sum[0];
}
inline float ei_predux(const v4f& a)
{
v4f b, sum;
b = (v4f)vec_sld(a, a, 8);
sum = vec_add(a, b);
b = (v4f)vec_sld(sum, sum, 4);
sum = vec_add(sum, b);
return ei_pfirst(sum);
}
inline int ei_predux(const v4i& a)
{
USE_CONST_v0i;
v4i sum;
sum = vec_sums(a, v0i);
sum = vec_sld(sum, v0i, 12);
return ei_pfirst(sum);
}
// implement other reductions operators
inline float ei_predux_mul(const v4f& a)
{
v4f prod;
prod = ei_pmul(a, (v4f)vec_sld(a, a, 8));
return ei_pfirst(ei_pmul(prod, (v4f)vec_sld(prod, prod, 4)));
}
inline int ei_predux_mul(const v4i& a)
{
EIGEN_ALIGN_128 int aux[4];
ei_pstore(aux, a);
return aux[0] * aux[1] * aux[2] * aux[3];
}
inline float ei_predux_min(const v4f& a)
{
v4f b, res;
b = vec_min(a, vec_sld(a, a, 8));
res = vec_min(b, vec_sld(b, b, 4));
return ei_pfirst(res);
}
inline int ei_predux_min(const v4i& a)
{
v4i b, res;
b = vec_min(a, vec_sld(a, a, 8));
res = vec_min(b, vec_sld(b, b, 4));
return ei_pfirst(res);
}
inline float ei_predux_max(const v4f& a)
{
v4f b, res;
b = vec_max(a, vec_sld(a, a, 8));
res = vec_max(b, vec_sld(b, b, 4));
return ei_pfirst(res);
}
inline int ei_predux_max(const v4i& a)
{
v4i b, res;
b = vec_max(a, vec_sld(a, a, 8));
res = vec_max(b, vec_sld(b, b, 4));
return ei_pfirst(res);
}
template<int Offset>
struct ei_palign_impl<Offset, v4f>
{
inline static void run(v4f& first, const v4f& second)
{
first = vec_sld(first, second, Offset*4);
}
};
template<int Offset>
struct ei_palign_impl<Offset, v4i>
{
inline static void run(v4i& first, const v4i& second)
{
first = vec_sld(first, second, Offset*4);
}
};
#endif // EIGEN_PACKET_MATH_ALTIVEC_H