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@freevec.org>
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#ifndef EIGEN_HAS_SINGLE_INSTRUCTION_MADD
24#define EIGEN_HAS_SINGLE_INSTRUCTION_MADD
25#endif
26
27#ifndef EIGEN_HAS_SINGLE_INSTRUCTION_CJMADD
28#define EIGEN_HAS_SINGLE_INSTRUCTION_CJMADD
29#endif
30
31#ifndef EIGEN_ARCH_DEFAULT_NUMBER_OF_REGISTERS
32#if EIGEN_ARCH_ARM64
33#define EIGEN_ARCH_DEFAULT_NUMBER_OF_REGISTERS 32
34#else
35#define EIGEN_ARCH_DEFAULT_NUMBER_OF_REGISTERS 16
36#endif
37#endif
38
39typedef float32x2_t Packet2f;
40typedef float32x4_t Packet4f;
41typedef int32x4_t   Packet4i;
42typedef int32x2_t   Packet2i;
43typedef uint32x4_t  Packet4ui;
44
45#define _EIGEN_DECLARE_CONST_Packet4f(NAME,X) \
46  const Packet4f p4f_##NAME = pset1<Packet4f>(X)
47
48#define _EIGEN_DECLARE_CONST_Packet4f_FROM_INT(NAME,X) \
49  const Packet4f p4f_##NAME = vreinterpretq_f32_u32(pset1<int32_t>(X))
50
51#define _EIGEN_DECLARE_CONST_Packet4i(NAME,X) \
52  const Packet4i p4i_##NAME = pset1<Packet4i>(X)
53
54#if EIGEN_ARCH_ARM64
55  // __builtin_prefetch tends to do nothing on ARM64 compilers because the
56  // prefetch instructions there are too detailed for __builtin_prefetch to map
57  // meaningfully to them.
58  #define EIGEN_ARM_PREFETCH(ADDR)  __asm__ __volatile__("prfm pldl1keep, [%[addr]]\n" ::[addr] "r"(ADDR) : );
59#elif EIGEN_HAS_BUILTIN(__builtin_prefetch) || EIGEN_COMP_GNUC
60  #define EIGEN_ARM_PREFETCH(ADDR) __builtin_prefetch(ADDR);
61#elif defined __pld
62  #define EIGEN_ARM_PREFETCH(ADDR) __pld(ADDR)
63#elif EIGEN_ARCH_ARM32
64  #define EIGEN_ARM_PREFETCH(ADDR) __asm__ __volatile__ ("pld [%[addr]]\n" :: [addr] "r" (ADDR) : );
65#else
66  // by default no explicit prefetching
67  #define EIGEN_ARM_PREFETCH(ADDR)
68#endif
69
70template<> struct packet_traits<float>  : default_packet_traits
71{
72  typedef Packet4f type;
73  typedef Packet4f half; // Packet2f intrinsics not implemented yet
74  enum {
75    Vectorizable = 1,
76    AlignedOnScalar = 1,
77    size = 4,
78    HasHalfPacket=0, // Packet2f intrinsics not implemented yet
79
80    HasDiv  = 1,
81    // FIXME check the Has*
82    HasSin  = 0,
83    HasCos  = 0,
84    HasLog  = 0,
85    HasExp  = 1,
86    HasSqrt = 0
87  };
88};
89template<> struct packet_traits<int32_t>    : default_packet_traits
90{
91  typedef Packet4i type;
92  typedef Packet4i half; // Packet2i intrinsics not implemented yet
93  enum {
94    Vectorizable = 1,
95    AlignedOnScalar = 1,
96    size=4,
97    HasHalfPacket=0 // Packet2i intrinsics not implemented yet
98    // FIXME check the Has*
99  };
100};
101
102#if EIGEN_GNUC_AT_MOST(4,4) && !EIGEN_COMP_LLVM
103// workaround gcc 4.2, 4.3 and 4.4 compilatin issue
104EIGEN_STRONG_INLINE float32x4_t vld1q_f32(const float* x) { return ::vld1q_f32((const float32_t*)x); }
105EIGEN_STRONG_INLINE float32x2_t vld1_f32 (const float* x) { return ::vld1_f32 ((const float32_t*)x); }
106EIGEN_STRONG_INLINE float32x2_t vld1_dup_f32 (const float* x) { return ::vld1_dup_f32 ((const float32_t*)x); }
107EIGEN_STRONG_INLINE void        vst1q_f32(float* to, float32x4_t from) { ::vst1q_f32((float32_t*)to,from); }
108EIGEN_STRONG_INLINE void        vst1_f32 (float* to, float32x2_t from) { ::vst1_f32 ((float32_t*)to,from); }
109#endif
110
111template<> struct unpacket_traits<Packet4f> { typedef float   type; enum {size=4, alignment=Aligned16}; typedef Packet4f half; };
112template<> struct unpacket_traits<Packet4i> { typedef int32_t type; enum {size=4, alignment=Aligned16}; typedef Packet4i half; };
113
114template<> EIGEN_STRONG_INLINE Packet4f pset1<Packet4f>(const float&  from) { return vdupq_n_f32(from); }
115template<> EIGEN_STRONG_INLINE Packet4i pset1<Packet4i>(const int32_t&    from)   { return vdupq_n_s32(from); }
116
117template<> EIGEN_STRONG_INLINE Packet4f plset<Packet4f>(const float& a)
118{
119  const float f[] = {0, 1, 2, 3};
120  Packet4f countdown = vld1q_f32(f);
121  return vaddq_f32(pset1<Packet4f>(a), countdown);
122}
123template<> EIGEN_STRONG_INLINE Packet4i plset<Packet4i>(const int32_t& a)
124{
125  const int32_t i[] = {0, 1, 2, 3};
126  Packet4i countdown = vld1q_s32(i);
127  return vaddq_s32(pset1<Packet4i>(a), countdown);
128}
129
130template<> EIGEN_STRONG_INLINE Packet4f padd<Packet4f>(const Packet4f& a, const Packet4f& b) { return vaddq_f32(a,b); }
131template<> EIGEN_STRONG_INLINE Packet4i padd<Packet4i>(const Packet4i& a, const Packet4i& b) { return vaddq_s32(a,b); }
132
133template<> EIGEN_STRONG_INLINE Packet4f psub<Packet4f>(const Packet4f& a, const Packet4f& b) { return vsubq_f32(a,b); }
134template<> EIGEN_STRONG_INLINE Packet4i psub<Packet4i>(const Packet4i& a, const Packet4i& b) { return vsubq_s32(a,b); }
135
136template<> EIGEN_STRONG_INLINE Packet4f pnegate(const Packet4f& a) { return vnegq_f32(a); }
137template<> EIGEN_STRONG_INLINE Packet4i pnegate(const Packet4i& a) { return vnegq_s32(a); }
138
139template<> EIGEN_STRONG_INLINE Packet4f pconj(const Packet4f& a) { return a; }
140template<> EIGEN_STRONG_INLINE Packet4i pconj(const Packet4i& a) { return a; }
141
142template<> EIGEN_STRONG_INLINE Packet4f pmul<Packet4f>(const Packet4f& a, const Packet4f& b) { return vmulq_f32(a,b); }
143template<> EIGEN_STRONG_INLINE Packet4i pmul<Packet4i>(const Packet4i& a, const Packet4i& b) { return vmulq_s32(a,b); }
144
145template<> EIGEN_STRONG_INLINE Packet4f pdiv<Packet4f>(const Packet4f& a, const Packet4f& b)
146{
147#if EIGEN_ARCH_ARM64
148  return vdivq_f32(a,b);
149#else
150  Packet4f inv, restep, div;
151
152  // NEON does not offer a divide instruction, we have to do a reciprocal approximation
153  // However NEON in contrast to other SIMD engines (AltiVec/SSE), offers
154  // a reciprocal estimate AND a reciprocal step -which saves a few instructions
155  // vrecpeq_f32() returns an estimate to 1/b, which we will finetune with
156  // Newton-Raphson and vrecpsq_f32()
157  inv = vrecpeq_f32(b);
158
159  // This returns a differential, by which we will have to multiply inv to get a better
160  // approximation of 1/b.
161  restep = vrecpsq_f32(b, inv);
162  inv = vmulq_f32(restep, inv);
163
164  // Finally, multiply a by 1/b and get the wanted result of the division.
165  div = vmulq_f32(a, inv);
166
167  return div;
168#endif
169}
170
171template<> EIGEN_STRONG_INLINE Packet4i pdiv<Packet4i>(const Packet4i& /*a*/, const Packet4i& /*b*/)
172{ eigen_assert(false && "packet integer division are not supported by NEON");
173  return pset1<Packet4i>(0);
174}
175
176// Clang/ARM wrongly advertises __ARM_FEATURE_FMA even when it's not available,
177// then implements a slow software scalar fallback calling fmaf()!
178// Filed LLVM bug:
179//     https://llvm.org/bugs/show_bug.cgi?id=27216
180#if (defined __ARM_FEATURE_FMA) && !(EIGEN_COMP_CLANG && EIGEN_ARCH_ARM)
181// See bug 936.
182// FMA is available on VFPv4 i.e. when compiling with -mfpu=neon-vfpv4.
183// FMA is a true fused multiply-add i.e. only 1 rounding at the end, no intermediate rounding.
184// MLA is not fused i.e. does 2 roundings.
185// In addition to giving better accuracy, FMA also gives better performance here on a Krait (Nexus 4):
186// MLA: 10 GFlop/s ; FMA: 12 GFlops/s.
187template<> EIGEN_STRONG_INLINE Packet4f pmadd(const Packet4f& a, const Packet4f& b, const Packet4f& c) { return vfmaq_f32(c,a,b); }
188#else
189template<> EIGEN_STRONG_INLINE Packet4f pmadd(const Packet4f& a, const Packet4f& b, const Packet4f& c) {
190#if EIGEN_COMP_CLANG && EIGEN_ARCH_ARM
191  // Clang/ARM will replace VMLA by VMUL+VADD at least for some values of -mcpu,
192  // at least -mcpu=cortex-a8 and -mcpu=cortex-a7. Since the former is the default on
193  // -march=armv7-a, that is a very common case.
194  // See e.g. this thread:
195  //     http://lists.llvm.org/pipermail/llvm-dev/2013-December/068806.html
196  // Filed LLVM bug:
197  //     https://llvm.org/bugs/show_bug.cgi?id=27219
198  Packet4f r = c;
199  asm volatile(
200    "vmla.f32 %q[r], %q[a], %q[b]"
201    : [r] "+w" (r)
202    : [a] "w" (a),
203      [b] "w" (b)
204    : );
205  return r;
206#else
207  return vmlaq_f32(c,a,b);
208#endif
209}
210#endif
211
212// No FMA instruction for int, so use MLA unconditionally.
213template<> EIGEN_STRONG_INLINE Packet4i pmadd(const Packet4i& a, const Packet4i& b, const Packet4i& c) { return vmlaq_s32(c,a,b); }
214
215template<> EIGEN_STRONG_INLINE Packet4f pmin<Packet4f>(const Packet4f& a, const Packet4f& b) { return vminq_f32(a,b); }
216template<> EIGEN_STRONG_INLINE Packet4i pmin<Packet4i>(const Packet4i& a, const Packet4i& b) { return vminq_s32(a,b); }
217
218template<> EIGEN_STRONG_INLINE Packet4f pmax<Packet4f>(const Packet4f& a, const Packet4f& b) { return vmaxq_f32(a,b); }
219template<> EIGEN_STRONG_INLINE Packet4i pmax<Packet4i>(const Packet4i& a, const Packet4i& b) { return vmaxq_s32(a,b); }
220
221// Logical Operations are not supported for float, so we have to reinterpret casts using NEON intrinsics
222template<> EIGEN_STRONG_INLINE Packet4f pand<Packet4f>(const Packet4f& a, const Packet4f& b)
223{
224  return vreinterpretq_f32_u32(vandq_u32(vreinterpretq_u32_f32(a),vreinterpretq_u32_f32(b)));
225}
226template<> EIGEN_STRONG_INLINE Packet4i pand<Packet4i>(const Packet4i& a, const Packet4i& b) { return vandq_s32(a,b); }
227
228template<> EIGEN_STRONG_INLINE Packet4f por<Packet4f>(const Packet4f& a, const Packet4f& b)
229{
230  return vreinterpretq_f32_u32(vorrq_u32(vreinterpretq_u32_f32(a),vreinterpretq_u32_f32(b)));
231}
232template<> EIGEN_STRONG_INLINE Packet4i por<Packet4i>(const Packet4i& a, const Packet4i& b) { return vorrq_s32(a,b); }
233
234template<> EIGEN_STRONG_INLINE Packet4f pxor<Packet4f>(const Packet4f& a, const Packet4f& b)
235{
236  return vreinterpretq_f32_u32(veorq_u32(vreinterpretq_u32_f32(a),vreinterpretq_u32_f32(b)));
237}
238template<> EIGEN_STRONG_INLINE Packet4i pxor<Packet4i>(const Packet4i& a, const Packet4i& b) { return veorq_s32(a,b); }
239
240template<> EIGEN_STRONG_INLINE Packet4f pandnot<Packet4f>(const Packet4f& a, const Packet4f& b)
241{
242  return vreinterpretq_f32_u32(vbicq_u32(vreinterpretq_u32_f32(a),vreinterpretq_u32_f32(b)));
243}
244template<> EIGEN_STRONG_INLINE Packet4i pandnot<Packet4i>(const Packet4i& a, const Packet4i& b) { return vbicq_s32(a,b); }
245
246template<> EIGEN_STRONG_INLINE Packet4f pload<Packet4f>(const float*    from) { EIGEN_DEBUG_ALIGNED_LOAD return vld1q_f32(from); }
247template<> EIGEN_STRONG_INLINE Packet4i pload<Packet4i>(const int32_t*  from) { EIGEN_DEBUG_ALIGNED_LOAD return vld1q_s32(from); }
248
249template<> EIGEN_STRONG_INLINE Packet4f ploadu<Packet4f>(const float*   from) { EIGEN_DEBUG_UNALIGNED_LOAD return vld1q_f32(from); }
250template<> EIGEN_STRONG_INLINE Packet4i ploadu<Packet4i>(const int32_t* from) { EIGEN_DEBUG_UNALIGNED_LOAD return vld1q_s32(from); }
251
252template<> EIGEN_STRONG_INLINE Packet4f ploaddup<Packet4f>(const float* from)
253{
254  float32x2_t lo, hi;
255  lo = vld1_dup_f32(from);
256  hi = vld1_dup_f32(from+1);
257  return vcombine_f32(lo, hi);
258}
259template<> EIGEN_STRONG_INLINE Packet4i ploaddup<Packet4i>(const int32_t* from)
260{
261  int32x2_t lo, hi;
262  lo = vld1_dup_s32(from);
263  hi = vld1_dup_s32(from+1);
264  return vcombine_s32(lo, hi);
265}
266
267template<> EIGEN_STRONG_INLINE void pstore<float>  (float*    to, const Packet4f& from) { EIGEN_DEBUG_ALIGNED_STORE vst1q_f32(to, from); }
268template<> EIGEN_STRONG_INLINE void pstore<int32_t>(int32_t*  to, const Packet4i& from) { EIGEN_DEBUG_ALIGNED_STORE vst1q_s32(to, from); }
269
270template<> EIGEN_STRONG_INLINE void pstoreu<float>  (float*   to, const Packet4f& from) { EIGEN_DEBUG_UNALIGNED_STORE vst1q_f32(to, from); }
271template<> EIGEN_STRONG_INLINE void pstoreu<int32_t>(int32_t* to, const Packet4i& from) { EIGEN_DEBUG_UNALIGNED_STORE vst1q_s32(to, from); }
272
273template<> EIGEN_DEVICE_FUNC inline Packet4f pgather<float, Packet4f>(const float* from, Index stride)
274{
275  Packet4f res = pset1<Packet4f>(0.f);
276  res = vsetq_lane_f32(from[0*stride], res, 0);
277  res = vsetq_lane_f32(from[1*stride], res, 1);
278  res = vsetq_lane_f32(from[2*stride], res, 2);
279  res = vsetq_lane_f32(from[3*stride], res, 3);
280  return res;
281}
282template<> EIGEN_DEVICE_FUNC inline Packet4i pgather<int32_t, Packet4i>(const int32_t* from, Index stride)
283{
284  Packet4i res = pset1<Packet4i>(0);
285  res = vsetq_lane_s32(from[0*stride], res, 0);
286  res = vsetq_lane_s32(from[1*stride], res, 1);
287  res = vsetq_lane_s32(from[2*stride], res, 2);
288  res = vsetq_lane_s32(from[3*stride], res, 3);
289  return res;
290}
291
292template<> EIGEN_DEVICE_FUNC inline void pscatter<float, Packet4f>(float* to, const Packet4f& from, Index stride)
293{
294  to[stride*0] = vgetq_lane_f32(from, 0);
295  to[stride*1] = vgetq_lane_f32(from, 1);
296  to[stride*2] = vgetq_lane_f32(from, 2);
297  to[stride*3] = vgetq_lane_f32(from, 3);
298}
299template<> EIGEN_DEVICE_FUNC inline void pscatter<int32_t, Packet4i>(int32_t* to, const Packet4i& from, Index stride)
300{
301  to[stride*0] = vgetq_lane_s32(from, 0);
302  to[stride*1] = vgetq_lane_s32(from, 1);
303  to[stride*2] = vgetq_lane_s32(from, 2);
304  to[stride*3] = vgetq_lane_s32(from, 3);
305}
306
307template<> EIGEN_STRONG_INLINE void prefetch<float>  (const float*    addr) { EIGEN_ARM_PREFETCH(addr); }
308template<> EIGEN_STRONG_INLINE void prefetch<int32_t>(const int32_t*  addr) { EIGEN_ARM_PREFETCH(addr); }
309
310// FIXME only store the 2 first elements ?
311template<> EIGEN_STRONG_INLINE float   pfirst<Packet4f>(const Packet4f& a) { float   EIGEN_ALIGN16 x[4]; vst1q_f32(x, a); return x[0]; }
312template<> EIGEN_STRONG_INLINE int32_t pfirst<Packet4i>(const Packet4i& a) { int32_t EIGEN_ALIGN16 x[4]; vst1q_s32(x, a); return x[0]; }
313
314template<> EIGEN_STRONG_INLINE Packet4f preverse(const Packet4f& a) {
315  float32x2_t a_lo, a_hi;
316  Packet4f a_r64;
317
318  a_r64 = vrev64q_f32(a);
319  a_lo = vget_low_f32(a_r64);
320  a_hi = vget_high_f32(a_r64);
321  return vcombine_f32(a_hi, a_lo);
322}
323template<> EIGEN_STRONG_INLINE Packet4i preverse(const Packet4i& a) {
324  int32x2_t a_lo, a_hi;
325  Packet4i a_r64;
326
327  a_r64 = vrev64q_s32(a);
328  a_lo = vget_low_s32(a_r64);
329  a_hi = vget_high_s32(a_r64);
330  return vcombine_s32(a_hi, a_lo);
331}
332
333template<> EIGEN_STRONG_INLINE Packet4f pabs(const Packet4f& a) { return vabsq_f32(a); }
334template<> EIGEN_STRONG_INLINE Packet4i pabs(const Packet4i& a) { return vabsq_s32(a); }
335
336template<> EIGEN_STRONG_INLINE float predux<Packet4f>(const Packet4f& a)
337{
338  float32x2_t a_lo, a_hi, sum;
339
340  a_lo = vget_low_f32(a);
341  a_hi = vget_high_f32(a);
342  sum = vpadd_f32(a_lo, a_hi);
343  sum = vpadd_f32(sum, sum);
344  return vget_lane_f32(sum, 0);
345}
346
347template<> EIGEN_STRONG_INLINE Packet4f preduxp<Packet4f>(const Packet4f* vecs)
348{
349  float32x4x2_t vtrn1, vtrn2, res1, res2;
350  Packet4f sum1, sum2, sum;
351
352  // NEON zip performs interleaving of the supplied vectors.
353  // We perform two interleaves in a row to acquire the transposed vector
354  vtrn1 = vzipq_f32(vecs[0], vecs[2]);
355  vtrn2 = vzipq_f32(vecs[1], vecs[3]);
356  res1 = vzipq_f32(vtrn1.val[0], vtrn2.val[0]);
357  res2 = vzipq_f32(vtrn1.val[1], vtrn2.val[1]);
358
359  // Do the addition of the resulting vectors
360  sum1 = vaddq_f32(res1.val[0], res1.val[1]);
361  sum2 = vaddq_f32(res2.val[0], res2.val[1]);
362  sum = vaddq_f32(sum1, sum2);
363
364  return sum;
365}
366
367template<> EIGEN_STRONG_INLINE int32_t predux<Packet4i>(const Packet4i& a)
368{
369  int32x2_t a_lo, a_hi, sum;
370
371  a_lo = vget_low_s32(a);
372  a_hi = vget_high_s32(a);
373  sum = vpadd_s32(a_lo, a_hi);
374  sum = vpadd_s32(sum, sum);
375  return vget_lane_s32(sum, 0);
376}
377
378template<> EIGEN_STRONG_INLINE Packet4i preduxp<Packet4i>(const Packet4i* vecs)
379{
380  int32x4x2_t vtrn1, vtrn2, res1, res2;
381  Packet4i sum1, sum2, sum;
382
383  // NEON zip performs interleaving of the supplied vectors.
384  // We perform two interleaves in a row to acquire the transposed vector
385  vtrn1 = vzipq_s32(vecs[0], vecs[2]);
386  vtrn2 = vzipq_s32(vecs[1], vecs[3]);
387  res1 = vzipq_s32(vtrn1.val[0], vtrn2.val[0]);
388  res2 = vzipq_s32(vtrn1.val[1], vtrn2.val[1]);
389
390  // Do the addition of the resulting vectors
391  sum1 = vaddq_s32(res1.val[0], res1.val[1]);
392  sum2 = vaddq_s32(res2.val[0], res2.val[1]);
393  sum = vaddq_s32(sum1, sum2);
394
395  return sum;
396}
397
398// Other reduction functions:
399// mul
400template<> EIGEN_STRONG_INLINE float predux_mul<Packet4f>(const Packet4f& a)
401{
402  float32x2_t a_lo, a_hi, prod;
403
404  // Get a_lo = |a1|a2| and a_hi = |a3|a4|
405  a_lo = vget_low_f32(a);
406  a_hi = vget_high_f32(a);
407  // Get the product of a_lo * a_hi -> |a1*a3|a2*a4|
408  prod = vmul_f32(a_lo, a_hi);
409  // Multiply prod with its swapped value |a2*a4|a1*a3|
410  prod = vmul_f32(prod, vrev64_f32(prod));
411
412  return vget_lane_f32(prod, 0);
413}
414template<> EIGEN_STRONG_INLINE int32_t predux_mul<Packet4i>(const Packet4i& a)
415{
416  int32x2_t a_lo, a_hi, prod;
417
418  // Get a_lo = |a1|a2| and a_hi = |a3|a4|
419  a_lo = vget_low_s32(a);
420  a_hi = vget_high_s32(a);
421  // Get the product of a_lo * a_hi -> |a1*a3|a2*a4|
422  prod = vmul_s32(a_lo, a_hi);
423  // Multiply prod with its swapped value |a2*a4|a1*a3|
424  prod = vmul_s32(prod, vrev64_s32(prod));
425
426  return vget_lane_s32(prod, 0);
427}
428
429// min
430template<> EIGEN_STRONG_INLINE float predux_min<Packet4f>(const Packet4f& a)
431{
432  float32x2_t a_lo, a_hi, min;
433
434  a_lo = vget_low_f32(a);
435  a_hi = vget_high_f32(a);
436  min = vpmin_f32(a_lo, a_hi);
437  min = vpmin_f32(min, min);
438
439  return vget_lane_f32(min, 0);
440}
441
442template<> EIGEN_STRONG_INLINE int32_t predux_min<Packet4i>(const Packet4i& a)
443{
444  int32x2_t a_lo, a_hi, min;
445
446  a_lo = vget_low_s32(a);
447  a_hi = vget_high_s32(a);
448  min = vpmin_s32(a_lo, a_hi);
449  min = vpmin_s32(min, min);
450
451  return vget_lane_s32(min, 0);
452}
453
454// max
455template<> EIGEN_STRONG_INLINE float predux_max<Packet4f>(const Packet4f& a)
456{
457  float32x2_t a_lo, a_hi, max;
458
459  a_lo = vget_low_f32(a);
460  a_hi = vget_high_f32(a);
461  max = vpmax_f32(a_lo, a_hi);
462  max = vpmax_f32(max, max);
463
464  return vget_lane_f32(max, 0);
465}
466
467template<> EIGEN_STRONG_INLINE int32_t predux_max<Packet4i>(const Packet4i& a)
468{
469  int32x2_t a_lo, a_hi, max;
470
471  a_lo = vget_low_s32(a);
472  a_hi = vget_high_s32(a);
473  max = vpmax_s32(a_lo, a_hi);
474  max = vpmax_s32(max, max);
475
476  return vget_lane_s32(max, 0);
477}
478
479// this PALIGN_NEON business is to work around a bug in LLVM Clang 3.0 causing incorrect compilation errors,
480// see bug 347 and this LLVM bug: http://llvm.org/bugs/show_bug.cgi?id=11074
481#define PALIGN_NEON(Offset,Type,Command) \
482template<>\
483struct palign_impl<Offset,Type>\
484{\
485    EIGEN_STRONG_INLINE static void run(Type& first, const Type& second)\
486    {\
487        if (Offset!=0)\
488            first = Command(first, second, Offset);\
489    }\
490};\
491
492PALIGN_NEON(0,Packet4f,vextq_f32)
493PALIGN_NEON(1,Packet4f,vextq_f32)
494PALIGN_NEON(2,Packet4f,vextq_f32)
495PALIGN_NEON(3,Packet4f,vextq_f32)
496PALIGN_NEON(0,Packet4i,vextq_s32)
497PALIGN_NEON(1,Packet4i,vextq_s32)
498PALIGN_NEON(2,Packet4i,vextq_s32)
499PALIGN_NEON(3,Packet4i,vextq_s32)
500
501#undef PALIGN_NEON
502
503EIGEN_DEVICE_FUNC inline void
504ptranspose(PacketBlock<Packet4f,4>& kernel) {
505  float32x4x2_t tmp1 = vzipq_f32(kernel.packet[0], kernel.packet[1]);
506  float32x4x2_t tmp2 = vzipq_f32(kernel.packet[2], kernel.packet[3]);
507
508  kernel.packet[0] = vcombine_f32(vget_low_f32(tmp1.val[0]), vget_low_f32(tmp2.val[0]));
509  kernel.packet[1] = vcombine_f32(vget_high_f32(tmp1.val[0]), vget_high_f32(tmp2.val[0]));
510  kernel.packet[2] = vcombine_f32(vget_low_f32(tmp1.val[1]), vget_low_f32(tmp2.val[1]));
511  kernel.packet[3] = vcombine_f32(vget_high_f32(tmp1.val[1]), vget_high_f32(tmp2.val[1]));
512}
513
514EIGEN_DEVICE_FUNC inline void
515ptranspose(PacketBlock<Packet4i,4>& kernel) {
516  int32x4x2_t tmp1 = vzipq_s32(kernel.packet[0], kernel.packet[1]);
517  int32x4x2_t tmp2 = vzipq_s32(kernel.packet[2], kernel.packet[3]);
518  kernel.packet[0] = vcombine_s32(vget_low_s32(tmp1.val[0]), vget_low_s32(tmp2.val[0]));
519  kernel.packet[1] = vcombine_s32(vget_high_s32(tmp1.val[0]), vget_high_s32(tmp2.val[0]));
520  kernel.packet[2] = vcombine_s32(vget_low_s32(tmp1.val[1]), vget_low_s32(tmp2.val[1]));
521  kernel.packet[3] = vcombine_s32(vget_high_s32(tmp1.val[1]), vget_high_s32(tmp2.val[1]));
522}
523
524//---------- double ----------
525
526// Clang 3.5 in the iOS toolchain has an ICE triggered by NEON intrisics for double.
527// Confirmed at least with __apple_build_version__ = 6000054.
528#ifdef __apple_build_version__
529// Let's hope that by the time __apple_build_version__ hits the 601* range, the bug will be fixed.
530// https://gist.github.com/yamaya/2924292 suggests that the 3 first digits are only updated with
531// major toolchain updates.
532#define EIGEN_APPLE_DOUBLE_NEON_BUG (__apple_build_version__ < 6010000)
533#else
534#define EIGEN_APPLE_DOUBLE_NEON_BUG 0
535#endif
536
537#if EIGEN_ARCH_ARM64 && !EIGEN_APPLE_DOUBLE_NEON_BUG
538
539// Bug 907: workaround missing declarations of the following two functions in the ADK
540// Defining these functions as templates ensures that if these intrinsics are
541// already defined in arm_neon.h, then our workaround doesn't cause a conflict
542// and has lower priority in overload resolution.
543template <typename T>
544uint64x2_t vreinterpretq_u64_f64(T a)
545{
546  return (uint64x2_t) a;
547}
548
549template <typename T>
550float64x2_t vreinterpretq_f64_u64(T a)
551{
552  return (float64x2_t) a;
553}
554
555typedef float64x2_t Packet2d;
556typedef float64x1_t Packet1d;
557
558template<> struct packet_traits<double>  : default_packet_traits
559{
560  typedef Packet2d type;
561  typedef Packet2d half;
562  enum {
563    Vectorizable = 1,
564    AlignedOnScalar = 1,
565    size = 2,
566    HasHalfPacket=0,
567
568    HasDiv  = 1,
569    // FIXME check the Has*
570    HasSin  = 0,
571    HasCos  = 0,
572    HasLog  = 0,
573    HasExp  = 0,
574    HasSqrt = 0
575  };
576};
577
578template<> struct unpacket_traits<Packet2d> { typedef double  type; enum {size=2, alignment=Aligned16}; typedef Packet2d half; };
579
580template<> EIGEN_STRONG_INLINE Packet2d pset1<Packet2d>(const double&  from) { return vdupq_n_f64(from); }
581
582template<> EIGEN_STRONG_INLINE Packet2d plset<Packet2d>(const double& a)
583{
584  const double countdown_raw[] = {0.0,1.0};
585  const Packet2d countdown = vld1q_f64(countdown_raw);
586  return vaddq_f64(pset1<Packet2d>(a), countdown);
587}
588template<> EIGEN_STRONG_INLINE Packet2d padd<Packet2d>(const Packet2d& a, const Packet2d& b) { return vaddq_f64(a,b); }
589
590template<> EIGEN_STRONG_INLINE Packet2d psub<Packet2d>(const Packet2d& a, const Packet2d& b) { return vsubq_f64(a,b); }
591
592template<> EIGEN_STRONG_INLINE Packet2d pnegate(const Packet2d& a) { return vnegq_f64(a); }
593
594template<> EIGEN_STRONG_INLINE Packet2d pconj(const Packet2d& a) { return a; }
595
596template<> EIGEN_STRONG_INLINE Packet2d pmul<Packet2d>(const Packet2d& a, const Packet2d& b) { return vmulq_f64(a,b); }
597
598template<> EIGEN_STRONG_INLINE Packet2d pdiv<Packet2d>(const Packet2d& a, const Packet2d& b) { return vdivq_f64(a,b); }
599
600#ifdef __ARM_FEATURE_FMA
601// See bug 936. See above comment about FMA for float.
602template<> EIGEN_STRONG_INLINE Packet2d pmadd(const Packet2d& a, const Packet2d& b, const Packet2d& c) { return vfmaq_f64(c,a,b); }
603#else
604template<> EIGEN_STRONG_INLINE Packet2d pmadd(const Packet2d& a, const Packet2d& b, const Packet2d& c) { return vmlaq_f64(c,a,b); }
605#endif
606
607template<> EIGEN_STRONG_INLINE Packet2d pmin<Packet2d>(const Packet2d& a, const Packet2d& b) { return vminq_f64(a,b); }
608
609template<> EIGEN_STRONG_INLINE Packet2d pmax<Packet2d>(const Packet2d& a, const Packet2d& b) { return vmaxq_f64(a,b); }
610
611// Logical Operations are not supported for float, so we have to reinterpret casts using NEON intrinsics
612template<> EIGEN_STRONG_INLINE Packet2d pand<Packet2d>(const Packet2d& a, const Packet2d& b)
613{
614  return vreinterpretq_f64_u64(vandq_u64(vreinterpretq_u64_f64(a),vreinterpretq_u64_f64(b)));
615}
616
617template<> EIGEN_STRONG_INLINE Packet2d por<Packet2d>(const Packet2d& a, const Packet2d& b)
618{
619  return vreinterpretq_f64_u64(vorrq_u64(vreinterpretq_u64_f64(a),vreinterpretq_u64_f64(b)));
620}
621
622template<> EIGEN_STRONG_INLINE Packet2d pxor<Packet2d>(const Packet2d& a, const Packet2d& b)
623{
624  return vreinterpretq_f64_u64(veorq_u64(vreinterpretq_u64_f64(a),vreinterpretq_u64_f64(b)));
625}
626
627template<> EIGEN_STRONG_INLINE Packet2d pandnot<Packet2d>(const Packet2d& a, const Packet2d& b)
628{
629  return vreinterpretq_f64_u64(vbicq_u64(vreinterpretq_u64_f64(a),vreinterpretq_u64_f64(b)));
630}
631
632template<> EIGEN_STRONG_INLINE Packet2d pload<Packet2d>(const double* from) { EIGEN_DEBUG_ALIGNED_LOAD return vld1q_f64(from); }
633
634template<> EIGEN_STRONG_INLINE Packet2d ploadu<Packet2d>(const double* from) { EIGEN_DEBUG_UNALIGNED_LOAD return vld1q_f64(from); }
635
636template<> EIGEN_STRONG_INLINE Packet2d ploaddup<Packet2d>(const double*   from)
637{
638  return vld1q_dup_f64(from);
639}
640template<> EIGEN_STRONG_INLINE void pstore<double>(double*   to, const Packet2d& from) { EIGEN_DEBUG_ALIGNED_STORE vst1q_f64(to, from); }
641
642template<> EIGEN_STRONG_INLINE void pstoreu<double>(double*  to, const Packet2d& from) { EIGEN_DEBUG_UNALIGNED_STORE vst1q_f64(to, from); }
643
644template<> EIGEN_DEVICE_FUNC inline Packet2d pgather<double, Packet2d>(const double* from, Index stride)
645{
646  Packet2d res = pset1<Packet2d>(0.0);
647  res = vsetq_lane_f64(from[0*stride], res, 0);
648  res = vsetq_lane_f64(from[1*stride], res, 1);
649  return res;
650}
651template<> EIGEN_DEVICE_FUNC inline void pscatter<double, Packet2d>(double* to, const Packet2d& from, Index stride)
652{
653  to[stride*0] = vgetq_lane_f64(from, 0);
654  to[stride*1] = vgetq_lane_f64(from, 1);
655}
656template<> EIGEN_STRONG_INLINE void prefetch<double>(const double* addr) { EIGEN_ARM_PREFETCH(addr); }
657
658// FIXME only store the 2 first elements ?
659template<> EIGEN_STRONG_INLINE double pfirst<Packet2d>(const Packet2d& a) { return vgetq_lane_f64(a, 0); }
660
661template<> EIGEN_STRONG_INLINE Packet2d preverse(const Packet2d& a) { return vcombine_f64(vget_high_f64(a), vget_low_f64(a)); }
662
663template<> EIGEN_STRONG_INLINE Packet2d pabs(const Packet2d& a) { return vabsq_f64(a); }
664
665#if EIGEN_COMP_CLANG && defined(__apple_build_version__)
666// workaround ICE, see bug 907
667template<> EIGEN_STRONG_INLINE double predux<Packet2d>(const Packet2d& a) { return (vget_low_f64(a) + vget_high_f64(a))[0]; }
668#else
669template<> EIGEN_STRONG_INLINE double predux<Packet2d>(const Packet2d& a) { return vget_lane_f64(vget_low_f64(a) + vget_high_f64(a), 0); }
670#endif
671
672template<> EIGEN_STRONG_INLINE Packet2d preduxp<Packet2d>(const Packet2d* vecs)
673{
674  float64x2_t trn1, trn2;
675
676  // NEON zip performs interleaving of the supplied vectors.
677  // We perform two interleaves in a row to acquire the transposed vector
678  trn1 = vzip1q_f64(vecs[0], vecs[1]);
679  trn2 = vzip2q_f64(vecs[0], vecs[1]);
680
681  // Do the addition of the resulting vectors
682  return vaddq_f64(trn1, trn2);
683}
684// Other reduction functions:
685// mul
686#if EIGEN_COMP_CLANG && defined(__apple_build_version__)
687template<> EIGEN_STRONG_INLINE double predux_mul<Packet2d>(const Packet2d& a) { return (vget_low_f64(a) * vget_high_f64(a))[0]; }
688#else
689template<> EIGEN_STRONG_INLINE double predux_mul<Packet2d>(const Packet2d& a) { return vget_lane_f64(vget_low_f64(a) * vget_high_f64(a), 0); }
690#endif
691
692// min
693template<> EIGEN_STRONG_INLINE double predux_min<Packet2d>(const Packet2d& a) { return vgetq_lane_f64(vpminq_f64(a, a), 0); }
694
695// max
696template<> EIGEN_STRONG_INLINE double predux_max<Packet2d>(const Packet2d& a) { return vgetq_lane_f64(vpmaxq_f64(a, a), 0); }
697
698// this PALIGN_NEON business is to work around a bug in LLVM Clang 3.0 causing incorrect compilation errors,
699// see bug 347 and this LLVM bug: http://llvm.org/bugs/show_bug.cgi?id=11074
700#define PALIGN_NEON(Offset,Type,Command) \
701template<>\
702struct palign_impl<Offset,Type>\
703{\
704    EIGEN_STRONG_INLINE static void run(Type& first, const Type& second)\
705    {\
706        if (Offset!=0)\
707            first = Command(first, second, Offset);\
708    }\
709};\
710
711PALIGN_NEON(0,Packet2d,vextq_f64)
712PALIGN_NEON(1,Packet2d,vextq_f64)
713#undef PALIGN_NEON
714
715EIGEN_DEVICE_FUNC inline void
716ptranspose(PacketBlock<Packet2d,2>& kernel) {
717  float64x2_t trn1 = vzip1q_f64(kernel.packet[0], kernel.packet[1]);
718  float64x2_t trn2 = vzip2q_f64(kernel.packet[0], kernel.packet[1]);
719
720  kernel.packet[0] = trn1;
721  kernel.packet[1] = trn2;
722}
723#endif // EIGEN_ARCH_ARM64
724
725} // end namespace internal
726
727} // end namespace Eigen
728
729#endif // EIGEN_PACKET_MATH_NEON_H
730