PacketMath.h revision 7faaa9f3f0df9d23790277834d426c3d992ac3ba
1// This file is part of Eigen, a lightweight C++ template library
2// for linear algebra.
3//
4// Copyright (C) 2008-2009 Gael Guennebaud <gael.guennebaud@inria.fr>
5// Copyright (C) 2010 Konstantinos Margaritis <markos@codex.gr>
6// Heavily based on Gael's SSE version.
7//
8// This Source Code Form is subject to the terms of the Mozilla
9// Public License v. 2.0. If a copy of the MPL was not distributed
10// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
11
12#ifndef EIGEN_PACKET_MATH_NEON_H
13#define EIGEN_PACKET_MATH_NEON_H
14
15namespace Eigen {
16
17namespace internal {
18
19#ifndef EIGEN_CACHEFRIENDLY_PRODUCT_THRESHOLD
20#define EIGEN_CACHEFRIENDLY_PRODUCT_THRESHOLD 8
21#endif
22
23// FIXME NEON has 16 quad registers, but since the current register allocator
24// is so bad, it is much better to reduce it to 8
25#ifndef EIGEN_ARCH_DEFAULT_NUMBER_OF_REGISTERS
26#define EIGEN_ARCH_DEFAULT_NUMBER_OF_REGISTERS 8
27#endif
28
29typedef float32x4_t Packet4f;
30typedef int32x4_t   Packet4i;
31typedef uint32x4_t  Packet4ui;
32
33#define _EIGEN_DECLARE_CONST_Packet4f(NAME,X) \
34  const Packet4f p4f_##NAME = pset1<Packet4f>(X)
35
36#define _EIGEN_DECLARE_CONST_Packet4f_FROM_INT(NAME,X) \
37  const Packet4f p4f_##NAME = vreinterpretq_f32_u32(pset1<int>(X))
38
39#define _EIGEN_DECLARE_CONST_Packet4i(NAME,X) \
40  const Packet4i p4i_##NAME = pset1<Packet4i>(X)
41
42#if defined(__llvm__) && !defined(__clang__)
43  //Special treatment for Apple's llvm-gcc, its NEON packet types are unions
44  #define EIGEN_INIT_NEON_PACKET2(X, Y)       {{X, Y}}
45  #define EIGEN_INIT_NEON_PACKET4(X, Y, Z, W) {{X, Y, Z, W}}
46#else
47  //Default initializer for packets
48  #define EIGEN_INIT_NEON_PACKET2(X, Y)       {X, Y}
49  #define EIGEN_INIT_NEON_PACKET4(X, Y, Z, W) {X, Y, Z, W}
50#endif
51
52#ifndef __pld
53#define __pld(x) asm volatile ( "   pld [%[addr]]\n" :: [addr] "r" (x) : "cc" );
54#endif
55
56template<> struct packet_traits<float>  : default_packet_traits
57{
58  typedef Packet4f type;
59  enum {
60    Vectorizable = 1,
61    AlignedOnScalar = 1,
62    size = 4,
63
64    HasDiv  = 1,
65    // FIXME check the Has*
66    HasSin  = 0,
67    HasCos  = 0,
68    HasLog  = 0,
69    HasExp  = 0,
70    HasSqrt = 0
71  };
72};
73template<> struct packet_traits<int>    : default_packet_traits
74{
75  typedef Packet4i type;
76  enum {
77    Vectorizable = 1,
78    AlignedOnScalar = 1,
79    size=4
80    // FIXME check the Has*
81  };
82};
83
84#if EIGEN_GNUC_AT_MOST(4,4) && !defined(__llvm__)
85// workaround gcc 4.2, 4.3 and 4.4 compilatin issue
86EIGEN_STRONG_INLINE float32x4_t vld1q_f32(const float* x) { return ::vld1q_f32((const float32_t*)x); }
87EIGEN_STRONG_INLINE float32x2_t vld1_f32 (const float* x) { return ::vld1_f32 ((const float32_t*)x); }
88EIGEN_STRONG_INLINE void        vst1q_f32(float* to, float32x4_t from) { ::vst1q_f32((float32_t*)to,from); }
89EIGEN_STRONG_INLINE void        vst1_f32 (float* to, float32x2_t from) { ::vst1_f32 ((float32_t*)to,from); }
90#endif
91
92template<> struct unpacket_traits<Packet4f> { typedef float  type; enum {size=4}; };
93template<> struct unpacket_traits<Packet4i> { typedef int    type; enum {size=4}; };
94
95template<> EIGEN_STRONG_INLINE Packet4f pset1<Packet4f>(const float&  from) { return vdupq_n_f32(from); }
96template<> EIGEN_STRONG_INLINE Packet4i pset1<Packet4i>(const int&    from)   { return vdupq_n_s32(from); }
97
98template<> EIGEN_STRONG_INLINE Packet4f plset<float>(const float& a)
99{
100  Packet4f countdown = EIGEN_INIT_NEON_PACKET4(0, 1, 2, 3);
101  return vaddq_f32(pset1<Packet4f>(a), countdown);
102}
103template<> EIGEN_STRONG_INLINE Packet4i plset<int>(const int& a)
104{
105  Packet4i countdown = EIGEN_INIT_NEON_PACKET4(0, 1, 2, 3);
106  return vaddq_s32(pset1<Packet4i>(a), countdown);
107}
108
109template<> EIGEN_STRONG_INLINE Packet4f padd<Packet4f>(const Packet4f& a, const Packet4f& b) { return vaddq_f32(a,b); }
110template<> EIGEN_STRONG_INLINE Packet4i padd<Packet4i>(const Packet4i& a, const Packet4i& b) { return vaddq_s32(a,b); }
111
112template<> EIGEN_STRONG_INLINE Packet4f psub<Packet4f>(const Packet4f& a, const Packet4f& b) { return vsubq_f32(a,b); }
113template<> EIGEN_STRONG_INLINE Packet4i psub<Packet4i>(const Packet4i& a, const Packet4i& b) { return vsubq_s32(a,b); }
114
115template<> EIGEN_STRONG_INLINE Packet4f pnegate(const Packet4f& a) { return vnegq_f32(a); }
116template<> EIGEN_STRONG_INLINE Packet4i pnegate(const Packet4i& a) { return vnegq_s32(a); }
117
118template<> EIGEN_STRONG_INLINE Packet4f pconj(const Packet4f& a) { return a; }
119template<> EIGEN_STRONG_INLINE Packet4i pconj(const Packet4i& a) { return a; }
120
121template<> EIGEN_STRONG_INLINE Packet4f pmul<Packet4f>(const Packet4f& a, const Packet4f& b) { return vmulq_f32(a,b); }
122template<> EIGEN_STRONG_INLINE Packet4i pmul<Packet4i>(const Packet4i& a, const Packet4i& b) { return vmulq_s32(a,b); }
123
124template<> EIGEN_STRONG_INLINE Packet4f pdiv<Packet4f>(const Packet4f& a, const Packet4f& b)
125{
126  Packet4f inv, restep, div;
127
128  // NEON does not offer a divide instruction, we have to do a reciprocal approximation
129  // However NEON in contrast to other SIMD engines (AltiVec/SSE), offers
130  // a reciprocal estimate AND a reciprocal step -which saves a few instructions
131  // vrecpeq_f32() returns an estimate to 1/b, which we will finetune with
132  // Newton-Raphson and vrecpsq_f32()
133  inv = vrecpeq_f32(b);
134
135  // This returns a differential, by which we will have to multiply inv to get a better
136  // approximation of 1/b.
137  restep = vrecpsq_f32(b, inv);
138  inv = vmulq_f32(restep, inv);
139
140  // Finally, multiply a by 1/b and get the wanted result of the division.
141  div = vmulq_f32(a, inv);
142
143  return div;
144}
145template<> EIGEN_STRONG_INLINE Packet4i pdiv<Packet4i>(const Packet4i& /*a*/, const Packet4i& /*b*/)
146{ eigen_assert(false && "packet integer division are not supported by NEON");
147  return pset1<Packet4i>(0);
148}
149
150// for some weird raisons, it has to be overloaded for packet of integers
151template<> EIGEN_STRONG_INLINE Packet4f pmadd(const Packet4f& a, const Packet4f& b, const Packet4f& c) { return vmlaq_f32(c,a,b); }
152template<> EIGEN_STRONG_INLINE Packet4i pmadd(const Packet4i& a, const Packet4i& b, const Packet4i& c) { return vmlaq_s32(c,a,b); }
153
154template<> EIGEN_STRONG_INLINE Packet4f pmin<Packet4f>(const Packet4f& a, const Packet4f& b) { return vminq_f32(a,b); }
155template<> EIGEN_STRONG_INLINE Packet4i pmin<Packet4i>(const Packet4i& a, const Packet4i& b) { return vminq_s32(a,b); }
156
157template<> EIGEN_STRONG_INLINE Packet4f pmax<Packet4f>(const Packet4f& a, const Packet4f& b) { return vmaxq_f32(a,b); }
158template<> EIGEN_STRONG_INLINE Packet4i pmax<Packet4i>(const Packet4i& a, const Packet4i& b) { return vmaxq_s32(a,b); }
159
160// Logical Operations are not supported for float, so we have to reinterpret casts using NEON intrinsics
161template<> EIGEN_STRONG_INLINE Packet4f pand<Packet4f>(const Packet4f& a, const Packet4f& b)
162{
163  return vreinterpretq_f32_u32(vandq_u32(vreinterpretq_u32_f32(a),vreinterpretq_u32_f32(b)));
164}
165template<> EIGEN_STRONG_INLINE Packet4i pand<Packet4i>(const Packet4i& a, const Packet4i& b) { return vandq_s32(a,b); }
166
167template<> EIGEN_STRONG_INLINE Packet4f por<Packet4f>(const Packet4f& a, const Packet4f& b)
168{
169  return vreinterpretq_f32_u32(vorrq_u32(vreinterpretq_u32_f32(a),vreinterpretq_u32_f32(b)));
170}
171template<> EIGEN_STRONG_INLINE Packet4i por<Packet4i>(const Packet4i& a, const Packet4i& b) { return vorrq_s32(a,b); }
172
173template<> EIGEN_STRONG_INLINE Packet4f pxor<Packet4f>(const Packet4f& a, const Packet4f& b)
174{
175  return vreinterpretq_f32_u32(veorq_u32(vreinterpretq_u32_f32(a),vreinterpretq_u32_f32(b)));
176}
177template<> EIGEN_STRONG_INLINE Packet4i pxor<Packet4i>(const Packet4i& a, const Packet4i& b) { return veorq_s32(a,b); }
178
179template<> EIGEN_STRONG_INLINE Packet4f pandnot<Packet4f>(const Packet4f& a, const Packet4f& b)
180{
181  return vreinterpretq_f32_u32(vbicq_u32(vreinterpretq_u32_f32(a),vreinterpretq_u32_f32(b)));
182}
183template<> EIGEN_STRONG_INLINE Packet4i pandnot<Packet4i>(const Packet4i& a, const Packet4i& b) { return vbicq_s32(a,b); }
184
185template<> EIGEN_STRONG_INLINE Packet4f pload<Packet4f>(const float* from) { EIGEN_DEBUG_ALIGNED_LOAD return vld1q_f32(from); }
186template<> EIGEN_STRONG_INLINE Packet4i pload<Packet4i>(const int*   from) { EIGEN_DEBUG_ALIGNED_LOAD return vld1q_s32(from); }
187
188template<> EIGEN_STRONG_INLINE Packet4f ploadu<Packet4f>(const float* from) { EIGEN_DEBUG_UNALIGNED_LOAD return vld1q_f32(from); }
189template<> EIGEN_STRONG_INLINE Packet4i ploadu<Packet4i>(const int* from)   { EIGEN_DEBUG_UNALIGNED_LOAD return vld1q_s32(from); }
190
191template<> EIGEN_STRONG_INLINE Packet4f ploaddup<Packet4f>(const float*   from)
192{
193  float32x2_t lo, hi;
194  lo = vld1_dup_f32(from);
195  hi = vld1_dup_f32(from+1);
196  return vcombine_f32(lo, hi);
197}
198template<> EIGEN_STRONG_INLINE Packet4i ploaddup<Packet4i>(const int*     from)
199{
200  int32x2_t lo, hi;
201  lo = vld1_dup_s32(from);
202  hi = vld1_dup_s32(from+1);
203  return vcombine_s32(lo, hi);
204}
205
206template<> EIGEN_STRONG_INLINE void pstore<float>(float*   to, const Packet4f& from) { EIGEN_DEBUG_ALIGNED_STORE vst1q_f32(to, from); }
207template<> EIGEN_STRONG_INLINE void pstore<int>(int*       to, const Packet4i& from) { EIGEN_DEBUG_ALIGNED_STORE vst1q_s32(to, from); }
208
209template<> EIGEN_STRONG_INLINE void pstoreu<float>(float*  to, const Packet4f& from) { EIGEN_DEBUG_UNALIGNED_STORE vst1q_f32(to, from); }
210template<> EIGEN_STRONG_INLINE void pstoreu<int>(int*      to, const Packet4i& from) { EIGEN_DEBUG_UNALIGNED_STORE vst1q_s32(to, from); }
211
212template<> EIGEN_STRONG_INLINE void prefetch<float>(const float* addr) { __pld(addr); }
213template<> EIGEN_STRONG_INLINE void prefetch<int>(const int*     addr) { __pld(addr); }
214
215// FIXME only store the 2 first elements ?
216template<> EIGEN_STRONG_INLINE float  pfirst<Packet4f>(const Packet4f& a) { float EIGEN_ALIGN16 x[4]; vst1q_f32(x, a); return x[0]; }
217template<> EIGEN_STRONG_INLINE int    pfirst<Packet4i>(const Packet4i& a) { int   EIGEN_ALIGN16 x[4]; vst1q_s32(x, a); return x[0]; }
218
219template<> EIGEN_STRONG_INLINE Packet4f preverse(const Packet4f& a) {
220  float32x2_t a_lo, a_hi;
221  Packet4f a_r64;
222
223  a_r64 = vrev64q_f32(a);
224  a_lo = vget_low_f32(a_r64);
225  a_hi = vget_high_f32(a_r64);
226  return vcombine_f32(a_hi, a_lo);
227}
228template<> EIGEN_STRONG_INLINE Packet4i preverse(const Packet4i& a) {
229  int32x2_t a_lo, a_hi;
230  Packet4i a_r64;
231
232  a_r64 = vrev64q_s32(a);
233  a_lo = vget_low_s32(a_r64);
234  a_hi = vget_high_s32(a_r64);
235  return vcombine_s32(a_hi, a_lo);
236}
237template<> EIGEN_STRONG_INLINE Packet4f pabs(const Packet4f& a) { return vabsq_f32(a); }
238template<> EIGEN_STRONG_INLINE Packet4i pabs(const Packet4i& a) { return vabsq_s32(a); }
239
240template<> EIGEN_STRONG_INLINE float predux<Packet4f>(const Packet4f& a)
241{
242  float32x2_t a_lo, a_hi, sum;
243
244  a_lo = vget_low_f32(a);
245  a_hi = vget_high_f32(a);
246  sum = vpadd_f32(a_lo, a_hi);
247  sum = vpadd_f32(sum, sum);
248  return vget_lane_f32(sum, 0);
249}
250
251template<> EIGEN_STRONG_INLINE Packet4f preduxp<Packet4f>(const Packet4f* vecs)
252{
253  float32x4x2_t vtrn1, vtrn2, res1, res2;
254  Packet4f sum1, sum2, sum;
255
256  // NEON zip performs interleaving of the supplied vectors.
257  // We perform two interleaves in a row to acquire the transposed vector
258  vtrn1 = vzipq_f32(vecs[0], vecs[2]);
259  vtrn2 = vzipq_f32(vecs[1], vecs[3]);
260  res1 = vzipq_f32(vtrn1.val[0], vtrn2.val[0]);
261  res2 = vzipq_f32(vtrn1.val[1], vtrn2.val[1]);
262
263  // Do the addition of the resulting vectors
264  sum1 = vaddq_f32(res1.val[0], res1.val[1]);
265  sum2 = vaddq_f32(res2.val[0], res2.val[1]);
266  sum = vaddq_f32(sum1, sum2);
267
268  return sum;
269}
270
271template<> EIGEN_STRONG_INLINE int predux<Packet4i>(const Packet4i& a)
272{
273  int32x2_t a_lo, a_hi, sum;
274
275  a_lo = vget_low_s32(a);
276  a_hi = vget_high_s32(a);
277  sum = vpadd_s32(a_lo, a_hi);
278  sum = vpadd_s32(sum, sum);
279  return vget_lane_s32(sum, 0);
280}
281
282template<> EIGEN_STRONG_INLINE Packet4i preduxp<Packet4i>(const Packet4i* vecs)
283{
284  int32x4x2_t vtrn1, vtrn2, res1, res2;
285  Packet4i sum1, sum2, sum;
286
287  // NEON zip performs interleaving of the supplied vectors.
288  // We perform two interleaves in a row to acquire the transposed vector
289  vtrn1 = vzipq_s32(vecs[0], vecs[2]);
290  vtrn2 = vzipq_s32(vecs[1], vecs[3]);
291  res1 = vzipq_s32(vtrn1.val[0], vtrn2.val[0]);
292  res2 = vzipq_s32(vtrn1.val[1], vtrn2.val[1]);
293
294  // Do the addition of the resulting vectors
295  sum1 = vaddq_s32(res1.val[0], res1.val[1]);
296  sum2 = vaddq_s32(res2.val[0], res2.val[1]);
297  sum = vaddq_s32(sum1, sum2);
298
299  return sum;
300}
301
302// Other reduction functions:
303// mul
304template<> EIGEN_STRONG_INLINE float predux_mul<Packet4f>(const Packet4f& a)
305{
306  float32x2_t a_lo, a_hi, prod;
307
308  // Get a_lo = |a1|a2| and a_hi = |a3|a4|
309  a_lo = vget_low_f32(a);
310  a_hi = vget_high_f32(a);
311  // Get the product of a_lo * a_hi -> |a1*a3|a2*a4|
312  prod = vmul_f32(a_lo, a_hi);
313  // Multiply prod with its swapped value |a2*a4|a1*a3|
314  prod = vmul_f32(prod, vrev64_f32(prod));
315
316  return vget_lane_f32(prod, 0);
317}
318template<> EIGEN_STRONG_INLINE int predux_mul<Packet4i>(const Packet4i& a)
319{
320  int32x2_t a_lo, a_hi, prod;
321
322  // Get a_lo = |a1|a2| and a_hi = |a3|a4|
323  a_lo = vget_low_s32(a);
324  a_hi = vget_high_s32(a);
325  // Get the product of a_lo * a_hi -> |a1*a3|a2*a4|
326  prod = vmul_s32(a_lo, a_hi);
327  // Multiply prod with its swapped value |a2*a4|a1*a3|
328  prod = vmul_s32(prod, vrev64_s32(prod));
329
330  return vget_lane_s32(prod, 0);
331}
332
333// min
334template<> EIGEN_STRONG_INLINE float predux_min<Packet4f>(const Packet4f& a)
335{
336  float32x2_t a_lo, a_hi, min;
337
338  a_lo = vget_low_f32(a);
339  a_hi = vget_high_f32(a);
340  min = vpmin_f32(a_lo, a_hi);
341  min = vpmin_f32(min, min);
342
343  return vget_lane_f32(min, 0);
344}
345
346template<> EIGEN_STRONG_INLINE int predux_min<Packet4i>(const Packet4i& a)
347{
348  int32x2_t a_lo, a_hi, min;
349
350  a_lo = vget_low_s32(a);
351  a_hi = vget_high_s32(a);
352  min = vpmin_s32(a_lo, a_hi);
353  min = vpmin_s32(min, min);
354
355  return vget_lane_s32(min, 0);
356}
357
358// max
359template<> EIGEN_STRONG_INLINE float predux_max<Packet4f>(const Packet4f& a)
360{
361  float32x2_t a_lo, a_hi, max;
362
363  a_lo = vget_low_f32(a);
364  a_hi = vget_high_f32(a);
365  max = vpmax_f32(a_lo, a_hi);
366  max = vpmax_f32(max, max);
367
368  return vget_lane_f32(max, 0);
369}
370
371template<> EIGEN_STRONG_INLINE int predux_max<Packet4i>(const Packet4i& a)
372{
373  int32x2_t a_lo, a_hi, max;
374
375  a_lo = vget_low_s32(a);
376  a_hi = vget_high_s32(a);
377  max = vpmax_s32(a_lo, a_hi);
378
379  return vget_lane_s32(max, 0);
380}
381
382// this PALIGN_NEON business is to work around a bug in LLVM Clang 3.0 causing incorrect compilation errors,
383// see bug 347 and this LLVM bug: http://llvm.org/bugs/show_bug.cgi?id=11074
384#define PALIGN_NEON(Offset,Type,Command) \
385template<>\
386struct palign_impl<Offset,Type>\
387{\
388    EIGEN_STRONG_INLINE static void run(Type& first, const Type& second)\
389    {\
390        if (Offset!=0)\
391            first = Command(first, second, Offset);\
392    }\
393};\
394
395PALIGN_NEON(0,Packet4f,vextq_f32)
396PALIGN_NEON(1,Packet4f,vextq_f32)
397PALIGN_NEON(2,Packet4f,vextq_f32)
398PALIGN_NEON(3,Packet4f,vextq_f32)
399PALIGN_NEON(0,Packet4i,vextq_s32)
400PALIGN_NEON(1,Packet4i,vextq_s32)
401PALIGN_NEON(2,Packet4i,vextq_s32)
402PALIGN_NEON(3,Packet4i,vextq_s32)
403
404#undef PALIGN_NEON
405
406} // end namespace internal
407
408} // end namespace Eigen
409
410#endif // EIGEN_PACKET_MATH_NEON_H
411