xref: /aosp_15_r20/external/XNNPACK/src/f32-vsigmoid/gen/vsigmoid-sse41-rr2-lut64-p2-div-x16.c (revision 4bdc94577ba0e567308109d787f7fec7b531ce36)
1 // Auto-generated file. Do not edit!
2 //   Template: src/f32-vsigmoid/sse-rr2-lut64-p2-div.c.in
3 //   Generator: tools/xngen
4 //
5 // Copyright 2020 Google LLC
6 //
7 // This source code is licensed under the BSD-style license found in the
8 // LICENSE file in the root directory of this source tree.
9 
10 #include <assert.h>
11 
12 #include <smmintrin.h>
13 
14 #include <xnnpack/common.h>
15 #include <xnnpack/vunary.h>
16 
17 
18 extern XNN_INTERNAL const float xnn_table_exp2minus_k_over_64[64];
19 
xnn_f32_vsigmoid_ukernel__sse41_rr2_lut64_p2_div_x16(size_t n,const float * x,float * y,const union xnn_f32_sigmoid_params params[restrict XNN_MIN_ELEMENTS (1)])20 void xnn_f32_vsigmoid_ukernel__sse41_rr2_lut64_p2_div_x16(
21     size_t n,
22     const float* x,
23     float* y,
24     const union xnn_f32_sigmoid_params params[restrict XNN_MIN_ELEMENTS(1)]) XNN_OOB_READS
25 {
26   assert(n % sizeof(float) == 0);
27 
28   const __m128 vsign_mask = _mm_load_ps(params->sse2_rr2_lut64_p2.sign_mask);
29   const __m128 vmagic_bias = _mm_load_ps(params->sse2_rr2_lut64_p2.magic_bias);
30   const __m128 vlog2e = _mm_load_ps(params->sse2_rr2_lut64_p2.log2e);
31   const __m128i vindex_mask = _mm_load_si128((const __m128i*) params->sse2_rr2_lut64_p2.index_mask);
32   const __m128 vminus_ln2_hi = _mm_load_ps(params->sse2_rr2_lut64_p2.minus_ln2_hi);
33   const __m128 vminus_ln2_lo = _mm_load_ps(params->sse2_rr2_lut64_p2.minus_ln2_lo);
34   const __m128 vc2 = _mm_load_ps(params->sse2_rr2_lut64_p2.c2);
35   const __m128 vone = _mm_load_ps(params->sse2_rr2_lut64_p2.one);
36   const __m128 vdenorm_cutoff = _mm_load_ps(params->sse2_rr2_lut64_p2.denorm_cutoff);
37 
38   for (; n >= 16 * sizeof(float); n -= 16 * sizeof(float)) {
39     const __m128 vx0123 = _mm_loadu_ps(x);
40     const __m128 vx4567 = _mm_loadu_ps(x + 4);
41     const __m128 vx89AB = _mm_loadu_ps(x + 8);
42     const __m128 vxCDEF = _mm_loadu_ps(x + 12);
43     x += 16;
44 
45     const __m128 vz0123 = _mm_or_ps(vx0123, vsign_mask);
46     const __m128 vz4567 = _mm_or_ps(vx4567, vsign_mask);
47     const __m128 vz89AB = _mm_or_ps(vx89AB, vsign_mask);
48     const __m128 vzCDEF = _mm_or_ps(vxCDEF, vsign_mask);
49 
50     __m128 vn0123 = _mm_add_ps(_mm_mul_ps(vz0123, vlog2e), vmagic_bias);
51     __m128 vn4567 = _mm_add_ps(_mm_mul_ps(vz4567, vlog2e), vmagic_bias);
52     __m128 vn89AB = _mm_add_ps(_mm_mul_ps(vz89AB, vlog2e), vmagic_bias);
53     __m128 vnCDEF = _mm_add_ps(_mm_mul_ps(vzCDEF, vlog2e), vmagic_bias);
54 
55     const __m128i ve0123 = _mm_slli_epi32(_mm_castps_si128(vn0123), 17);
56     const __m128i ve4567 = _mm_slli_epi32(_mm_castps_si128(vn4567), 17);
57     const __m128i ve89AB = _mm_slli_epi32(_mm_castps_si128(vn89AB), 17);
58     const __m128i veCDEF = _mm_slli_epi32(_mm_castps_si128(vnCDEF), 17);
59 
60     const __m128i vidx0123 = _mm_slli_epi32(_mm_and_si128(_mm_castps_si128(vn0123), vindex_mask), 2);
61     const __m128i vidx4567 = _mm_slli_epi32(_mm_and_si128(_mm_castps_si128(vn4567), vindex_mask), 2);
62     const __m128i vidx89AB = _mm_slli_epi32(_mm_and_si128(_mm_castps_si128(vn89AB), vindex_mask), 2);
63     const __m128i vidxCDEF = _mm_slli_epi32(_mm_and_si128(_mm_castps_si128(vnCDEF), vindex_mask), 2);
64 
65     #if XNN_ARCH_X86_64
66       const uint64_t vidx01 = (uint64_t) _mm_cvtsi128_si64(vidx0123);
67       const uint64_t vidx23 = (uint64_t) _mm_extract_epi64(vidx0123, 1);
68       const __m128i vl0   = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) vidx01)));
69       const __m128i vl2 = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) vidx23)));
70       const __m128i vl01 = _mm_insert_epi32(vl0, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) (vidx01 >> 32))), 1);
71       const __m128i vl23 = _mm_insert_epi32(vl2, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) (vidx23 >> 32))), 1);
72       const __m128i vl0123 = _mm_unpacklo_epi64(vl01, vl23);
73       const uint64_t vidx45 = (uint64_t) _mm_cvtsi128_si64(vidx4567);
74       const uint64_t vidx67 = (uint64_t) _mm_extract_epi64(vidx4567, 1);
75       const __m128i vl4   = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) vidx45)));
76       const __m128i vl6 = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) vidx67)));
77       const __m128i vl45 = _mm_insert_epi32(vl4, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) (vidx45 >> 32))), 1);
78       const __m128i vl67 = _mm_insert_epi32(vl6, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) (vidx67 >> 32))), 1);
79       const __m128i vl4567 = _mm_unpacklo_epi64(vl45, vl67);
80       const uint64_t vidx89 = (uint64_t) _mm_cvtsi128_si64(vidx89AB);
81       const uint64_t vidxAB = (uint64_t) _mm_extract_epi64(vidx89AB, 1);
82       const __m128i vl8   = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) vidx89)));
83       const __m128i vlA = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) vidxAB)));
84       const __m128i vl89 = _mm_insert_epi32(vl8, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) (vidx89 >> 32))), 1);
85       const __m128i vlAB = _mm_insert_epi32(vlA, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) (vidxAB >> 32))), 1);
86       const __m128i vl89AB = _mm_unpacklo_epi64(vl89, vlAB);
87       const uint64_t vidxCD = (uint64_t) _mm_cvtsi128_si64(vidxCDEF);
88       const uint64_t vidxEF = (uint64_t) _mm_extract_epi64(vidxCDEF, 1);
89       const __m128i vlC   = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) vidxCD)));
90       const __m128i vlE = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) vidxEF)));
91       const __m128i vlCD = _mm_insert_epi32(vlC, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) (vidxCD >> 32))), 1);
92       const __m128i vlEF = _mm_insert_epi32(vlE, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) (vidxEF >> 32))), 1);
93       const __m128i vlCDEF = _mm_unpacklo_epi64(vlCD, vlEF);
94     #else  // !XNN_ARCH_X86_64
95       const uint32_t vidx0 = (uint32_t) _mm_cvtsi128_si32(vidx0123);
96       const uint32_t vidx1 = (uint32_t) _mm_extract_epi16(vidx0123, 2);
97       const uint32_t vidx2 = (uint32_t) _mm_extract_epi16(vidx0123, 4);
98       const uint32_t vidx3 = (uint32_t) _mm_extract_epi16(vidx0123, 6);
99       const __m128i vl0   = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + vidx0)));
100       const __m128i vl2 = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + vidx2)));
101       const __m128i vl01 = _mm_insert_epi32(vl0, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + vidx1)), 1);
102       const __m128i vl23 = _mm_insert_epi32(vl2, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + vidx3)), 1);
103       const __m128i vl0123 = _mm_unpacklo_epi64(vl01, vl23);
104       const uint32_t vidx4 = (uint32_t) _mm_cvtsi128_si32(vidx4567);
105       const uint32_t vidx5 = (uint32_t) _mm_extract_epi16(vidx4567, 2);
106       const uint32_t vidx6 = (uint32_t) _mm_extract_epi16(vidx4567, 4);
107       const uint32_t vidx7 = (uint32_t) _mm_extract_epi16(vidx4567, 6);
108       const __m128i vl4   = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + vidx4)));
109       const __m128i vl6 = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + vidx6)));
110       const __m128i vl45 = _mm_insert_epi32(vl4, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + vidx5)), 1);
111       const __m128i vl67 = _mm_insert_epi32(vl6, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + vidx7)), 1);
112       const __m128i vl4567 = _mm_unpacklo_epi64(vl45, vl67);
113       const uint32_t vidx8 = (uint32_t) _mm_cvtsi128_si32(vidx89AB);
114       const uint32_t vidx9 = (uint32_t) _mm_extract_epi16(vidx89AB, 2);
115       const uint32_t vidxA = (uint32_t) _mm_extract_epi16(vidx89AB, 4);
116       const uint32_t vidxB = (uint32_t) _mm_extract_epi16(vidx89AB, 6);
117       const __m128i vl8   = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + vidx8)));
118       const __m128i vlA = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + vidxA)));
119       const __m128i vl89 = _mm_insert_epi32(vl8, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + vidx9)), 1);
120       const __m128i vlAB = _mm_insert_epi32(vlA, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + vidxB)), 1);
121       const __m128i vl89AB = _mm_unpacklo_epi64(vl89, vlAB);
122       const uint32_t vidxC = (uint32_t) _mm_cvtsi128_si32(vidxCDEF);
123       const uint32_t vidxD = (uint32_t) _mm_extract_epi16(vidxCDEF, 2);
124       const uint32_t vidxE = (uint32_t) _mm_extract_epi16(vidxCDEF, 4);
125       const uint32_t vidxF = (uint32_t) _mm_extract_epi16(vidxCDEF, 6);
126       const __m128i vlC   = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + vidxC)));
127       const __m128i vlE = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + vidxE)));
128       const __m128i vlCD = _mm_insert_epi32(vlC, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + vidxD)), 1);
129       const __m128i vlEF = _mm_insert_epi32(vlE, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + vidxF)), 1);
130       const __m128i vlCDEF = _mm_unpacklo_epi64(vlCD, vlEF);
131     #endif  // XNN_ARCH_X86_64
132 
133     const __m128 vs0123 = _mm_castsi128_ps(_mm_add_epi32(vl0123, ve0123));
134     const __m128 vs4567 = _mm_castsi128_ps(_mm_add_epi32(vl4567, ve4567));
135     const __m128 vs89AB = _mm_castsi128_ps(_mm_add_epi32(vl89AB, ve89AB));
136     const __m128 vsCDEF = _mm_castsi128_ps(_mm_add_epi32(vlCDEF, veCDEF));
137 
138     vn0123 = _mm_sub_ps(vn0123, vmagic_bias);
139     vn4567 = _mm_sub_ps(vn4567, vmagic_bias);
140     vn89AB = _mm_sub_ps(vn89AB, vmagic_bias);
141     vnCDEF = _mm_sub_ps(vnCDEF, vmagic_bias);
142 
143     __m128 vt0123 = _mm_add_ps(vz0123, _mm_mul_ps(vn0123, vminus_ln2_hi));
144     __m128 vt4567 = _mm_add_ps(vz4567, _mm_mul_ps(vn4567, vminus_ln2_hi));
145     __m128 vt89AB = _mm_add_ps(vz89AB, _mm_mul_ps(vn89AB, vminus_ln2_hi));
146     __m128 vtCDEF = _mm_add_ps(vzCDEF, _mm_mul_ps(vnCDEF, vminus_ln2_hi));
147 
148     vt0123 = _mm_add_ps(vt0123, _mm_mul_ps(vn0123, vminus_ln2_lo));
149     vt4567 = _mm_add_ps(vt4567, _mm_mul_ps(vn4567, vminus_ln2_lo));
150     vt89AB = _mm_add_ps(vt89AB, _mm_mul_ps(vn89AB, vminus_ln2_lo));
151     vtCDEF = _mm_add_ps(vtCDEF, _mm_mul_ps(vnCDEF, vminus_ln2_lo));
152 
153     __m128 vp0123 = _mm_mul_ps(vt0123, vc2);
154     __m128 vp4567 = _mm_mul_ps(vt4567, vc2);
155     __m128 vp89AB = _mm_mul_ps(vt89AB, vc2);
156     __m128 vpCDEF = _mm_mul_ps(vtCDEF, vc2);
157 
158     vp0123 = _mm_add_ps(vt0123, _mm_mul_ps(vp0123, vt0123));
159     vp4567 = _mm_add_ps(vt4567, _mm_mul_ps(vp4567, vt4567));
160     vp89AB = _mm_add_ps(vt89AB, _mm_mul_ps(vp89AB, vt89AB));
161     vpCDEF = _mm_add_ps(vtCDEF, _mm_mul_ps(vpCDEF, vtCDEF));
162 
163     const __m128 vy0123 = _mm_add_ps(vs0123, _mm_mul_ps(vs0123, vp0123));
164     const __m128 vy4567 = _mm_add_ps(vs4567, _mm_mul_ps(vs4567, vp4567));
165     const __m128 vy89AB = _mm_add_ps(vs89AB, _mm_mul_ps(vs89AB, vp89AB));
166     const __m128 vyCDEF = _mm_add_ps(vsCDEF, _mm_mul_ps(vsCDEF, vpCDEF));
167 
168     __m128 vf0123 = _mm_div_ps(vy0123, _mm_add_ps(vy0123, vone));
169     __m128 vf4567 = _mm_div_ps(vy4567, _mm_add_ps(vy4567, vone));
170     __m128 vf89AB = _mm_div_ps(vy89AB, _mm_add_ps(vy89AB, vone));
171     __m128 vfCDEF = _mm_div_ps(vyCDEF, _mm_add_ps(vyCDEF, vone));
172 
173     vf0123 = _mm_andnot_ps(_mm_cmplt_ps(vz0123, vdenorm_cutoff), vf0123);
174     vf4567 = _mm_andnot_ps(_mm_cmplt_ps(vz4567, vdenorm_cutoff), vf4567);
175     vf89AB = _mm_andnot_ps(_mm_cmplt_ps(vz89AB, vdenorm_cutoff), vf89AB);
176     vfCDEF = _mm_andnot_ps(_mm_cmplt_ps(vzCDEF, vdenorm_cutoff), vfCDEF);
177 
178     vf0123 = _mm_blendv_ps(_mm_sub_ps(vone, vf0123), vf0123, vx0123);
179     vf4567 = _mm_blendv_ps(_mm_sub_ps(vone, vf4567), vf4567, vx4567);
180     vf89AB = _mm_blendv_ps(_mm_sub_ps(vone, vf89AB), vf89AB, vx89AB);
181     vfCDEF = _mm_blendv_ps(_mm_sub_ps(vone, vfCDEF), vfCDEF, vxCDEF);
182 
183     _mm_storeu_ps(y, vf0123);
184     _mm_storeu_ps(y + 4, vf4567);
185     _mm_storeu_ps(y + 8, vf89AB);
186     _mm_storeu_ps(y + 12, vfCDEF);
187     y += 16;
188   }
189   for (; n >= 4 * sizeof(float); n -= 4 * sizeof(float)) {
190     const __m128 vx = _mm_loadu_ps(x);
191     x += 4;
192 
193     const __m128 vz = _mm_or_ps(vx, vsign_mask);
194 
195     __m128 vn = _mm_add_ps(_mm_mul_ps(vz, vlog2e), vmagic_bias);
196     const __m128i ve = _mm_slli_epi32(_mm_castps_si128(vn), 17);
197 
198     const __m128i vidx = _mm_slli_epi32(_mm_and_si128(_mm_castps_si128(vn), vindex_mask), 2);
199     #if XNN_ARCH_X86_64
200       const uint64_t vidx_lo = (uint64_t) _mm_cvtsi128_si64(vidx);
201       const uint64_t vidx_hi = (uint64_t) _mm_extract_epi64(vidx, 1);
202       const __m128i vl_ll   = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) vidx_lo)));
203       const __m128i vl_hl = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) vidx_hi)));
204       const __m128i vl_lo = _mm_insert_epi32(vl_ll, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) (vidx_lo >> 32))), 1);
205       const __m128i vl_hi = _mm_insert_epi32(vl_hl, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) (vidx_hi >> 32))), 1);
206     #else  // !XNN_ARCH_X86_64
207       const __m128i vl_ll = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) _mm_cvtsi128_si32(vidx))));
208       const __m128i vl_hl = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) _mm_extract_epi16(vidx, 4))));
209       const __m128i vl_lo = _mm_insert_epi32(vl_ll, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) _mm_extract_epi16(vidx, 2))), 1);
210       const __m128i vl_hi = _mm_insert_epi32(vl_hl, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) _mm_extract_epi16(vidx, 6))), 1);
211     #endif  // XNN_ARCH_X86_64
212     const __m128i vl = _mm_unpacklo_epi64(vl_lo, vl_hi);
213 
214     const __m128 vs = _mm_castsi128_ps(_mm_add_epi32(vl, ve));
215     vn = _mm_sub_ps(vn, vmagic_bias);
216 
217     __m128 vt = _mm_add_ps(vz, _mm_mul_ps(vn, vminus_ln2_hi));
218     vt = _mm_add_ps(vt, _mm_mul_ps(vn, vminus_ln2_lo));
219 
220     __m128 vp = _mm_mul_ps(vt, vc2);
221     vp = _mm_add_ps(vt, _mm_mul_ps(vp, vt));
222 
223     const __m128 vy = _mm_add_ps(vs, _mm_mul_ps(vs, vp));
224 
225     __m128 vf = _mm_div_ps(vy, _mm_add_ps(vy, vone));
226     vf = _mm_andnot_ps(_mm_cmplt_ps(vz, vdenorm_cutoff), vf);
227     vf = _mm_blendv_ps(_mm_sub_ps(vone, vf), vf, vx);
228 
229     _mm_storeu_ps(y, vf);
230     y += 4;
231   }
232   if XNN_UNLIKELY(n != 0) {
233     const __m128 vx = _mm_loadu_ps(x);
234 
235     const __m128 vz = _mm_or_ps(vx, vsign_mask);
236 
237     __m128 vn = _mm_add_ps(_mm_mul_ps(vz, vlog2e), vmagic_bias);
238     const __m128i ve = _mm_slli_epi32(_mm_castps_si128(vn), 17);
239 
240     const __m128i vidx = _mm_slli_epi32(_mm_and_si128(_mm_castps_si128(vn), vindex_mask), 2);
241     #if XNN_ARCH_X86_64
242       const uint64_t vidx_lo = (uint64_t) _mm_cvtsi128_si64(vidx);
243       const uint64_t vidx_hi = (uint64_t) _mm_extract_epi64(vidx, 1);
244       const __m128i vl_ll   = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) vidx_lo)));
245       const __m128i vl_hl = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) vidx_hi)));
246       const __m128i vl_lo = _mm_insert_epi32(vl_ll, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) (vidx_lo >> 32))), 1);
247       const __m128i vl_hi = _mm_insert_epi32(vl_hl, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) (vidx_hi >> 32))), 1);
248     #else  // !XNN_ARCH_X86_64
249       const __m128i vl_ll = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) _mm_cvtsi128_si32(vidx))));
250       const __m128i vl_hl = _mm_cvtsi32_si128(*((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) _mm_extract_epi16(vidx, 4))));
251       const __m128i vl_lo = _mm_insert_epi32(vl_ll, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) _mm_extract_epi16(vidx, 2))), 1);
252       const __m128i vl_hi = _mm_insert_epi32(vl_hl, *((const int*) ((uintptr_t) xnn_table_exp2minus_k_over_64 + (uint32_t) _mm_extract_epi16(vidx, 6))), 1);
253     #endif  // XNN_ARCH_X86_64
254     const __m128i vl = _mm_unpacklo_epi64(vl_lo, vl_hi);
255 
256     const __m128 vs = _mm_castsi128_ps(_mm_add_epi32(vl, ve));
257     vn = _mm_sub_ps(vn, vmagic_bias);
258 
259     __m128 vt = _mm_add_ps(vz, _mm_mul_ps(vn, vminus_ln2_hi));
260     vt = _mm_add_ps(vt, _mm_mul_ps(vn, vminus_ln2_lo));
261 
262     __m128 vp = _mm_mul_ps(vt, vc2);
263     vp = _mm_add_ps(vt, _mm_mul_ps(vp, vt));
264 
265     const __m128 vy = _mm_add_ps(vs, _mm_mul_ps(vs, vp));
266 
267     __m128 vf = _mm_div_ps(vy, _mm_add_ps(vy, vone));
268     vf = _mm_andnot_ps(_mm_cmplt_ps(vz, vdenorm_cutoff), vf);
269     vf = _mm_blendv_ps(_mm_sub_ps(vone, vf), vf, vx);
270 
271     if (n & (2 * sizeof(float))) {
272       _mm_storel_pi((__m64*) y, vf);
273       vf = _mm_movehl_ps(vf, vf);
274       y += 2;
275     }
276     if (n & (1 * sizeof(float))) {
277       _mm_store_ss(y, vf);
278     }
279   }
280 }
281