1 // Auto-generated file. Do not edit!
2 // Template: src/cs16-bfly4/scalar.c.in
3 // Generator: tools/xngen
4 //
5 // Copyright 2022 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 #include <stddef.h>
12 #include <stdint.h>
13
14 #include <xnnpack/math.h>
15 #include <xnnpack/fft.h>
16
17
xnn_cs16_bfly4_ukernel__scalar_x1(size_t samples,int16_t * data,const size_t stride,const int16_t * twiddle)18 void xnn_cs16_bfly4_ukernel__scalar_x1(
19 size_t samples,
20 int16_t* data,
21 const size_t stride,
22 const int16_t* twiddle)
23 {
24 const int16_t* tw1 = twiddle;
25 const int16_t* tw2 = twiddle;
26 const int16_t* tw3 = twiddle;
27 int16_t* data0 = data;
28 int16_t* data1 = data + samples * 2;
29 int16_t* data2 = data + samples * 4;
30 int16_t* data3 = data + samples * 6;
31
32 assert(samples != 0);
33 assert(data != NULL);
34 assert(stride != 0);
35 assert(twiddle != NULL);
36
37
38 if XNN_UNLIKELY(samples != 0) {
39 do {
40 int32_t vout0r = (int32_t) data0[0];
41 int32_t vout0i = (int32_t) data0[1];
42 int32_t vout1r = (int32_t) data1[0];
43 int32_t vout1i = (int32_t) data1[1];
44 int32_t vout2r = (int32_t) data2[0];
45 int32_t vout2i = (int32_t) data2[1];
46 int32_t vout3r = (int32_t) data3[0];
47 int32_t vout3i = (int32_t) data3[1];
48
49 const int32_t vtw1r = (const int32_t) tw1[0];
50 const int32_t vtw1i = (const int32_t) tw1[1];
51 const int32_t vtw2r = (const int32_t) tw2[0];
52 const int32_t vtw2i = (const int32_t) tw2[1];
53 const int32_t vtw3r = (const int32_t) tw3[0];
54 const int32_t vtw3i = (const int32_t) tw3[1];
55 tw1 += stride * 2;
56 tw2 += stride * 4;
57 tw3 += stride * 6;
58
59 // Note 32767 / 4 = 8191. Should be 8192.
60 vout0r = math_asr_s32(vout0r * 8191 + 16384, 15);
61 vout0i = math_asr_s32(vout0i * 8191 + 16384, 15);
62 vout1r = math_asr_s32(vout1r * 8191 + 16384, 15);
63 vout1i = math_asr_s32(vout1i * 8191 + 16384, 15);
64 vout2r = math_asr_s32(vout2r * 8191 + 16384, 15);
65 vout2i = math_asr_s32(vout2i * 8191 + 16384, 15);
66 vout3r = math_asr_s32(vout3r * 8191 + 16384, 15);
67 vout3i = math_asr_s32(vout3i * 8191 + 16384, 15);
68
69 const int32_t vtmp0r = math_asr_s32(vout1r * vtw1r - vout1i * vtw1i + 16384, 15);
70 const int32_t vtmp0i = math_asr_s32(vout1r * vtw1i + vout1i * vtw1r + 16384, 15);
71 const int32_t vtmp1r = math_asr_s32(vout2r * vtw2r - vout2i * vtw2i + 16384, 15);
72 const int32_t vtmp1i = math_asr_s32(vout2r * vtw2i + vout2i * vtw2r + 16384, 15);
73 const int32_t vtmp2r = math_asr_s32(vout3r * vtw3r - vout3i * vtw3i + 16384, 15);
74 const int32_t vtmp2i = math_asr_s32(vout3r * vtw3i + vout3i * vtw3r + 16384, 15);
75
76 const int32_t vtmp5r = vout0r - vtmp1r;
77 const int32_t vtmp5i = vout0i - vtmp1i;
78 vout0r += vtmp1r;
79 vout0i += vtmp1i;
80 const int32_t vtmp3r = vtmp0r + vtmp2r;
81 const int32_t vtmp3i = vtmp0i + vtmp2i;
82 const int32_t vtmp4r = vtmp0r - vtmp2r;
83 const int32_t vtmp4i = vtmp0i - vtmp2i;
84 vout2r = vout0r - vtmp3r;
85 vout2i = vout0i - vtmp3i;
86
87 vout0r += vtmp3r;
88 vout0i += vtmp3i;
89
90 vout1r = vtmp5r + vtmp4i;
91 vout1i = vtmp5i - vtmp4r;
92 vout3r = vtmp5r - vtmp4i;
93 vout3i = vtmp5i + vtmp4r;
94
95 data0[0] = (int16_t) vout0r;
96 data0[1] = (int16_t) vout0i;
97 data1[0] = (int16_t) vout1r;
98 data1[1] = (int16_t) vout1i;
99 data2[0] = (int16_t) vout2r;
100 data2[1] = (int16_t) vout2i;
101 data3[0] = (int16_t) vout3r;
102 data3[1] = (int16_t) vout3i;
103 data0 += 2;
104 data1 += 2;
105 data2 += 2;
106 data3 += 2;
107 } while(--samples != 0);
108 }
109 }
110