1 // Copyright (c) Facebook, Inc. and its affiliates.
2 // All rights reserved.
3 //
4 // Copyright 2019 Google LLC
5 //
6 // This source code is licensed under the BSD-style license found in the
7 // LICENSE file in the root directory of this source tree.
8
9 #include <assert.h>
10 #include <math.h>
11 #include <stdint.h>
12 #include <stddef.h>
13
14 #include <fp16/bitcasts.h>
15
16 #include <xnnpack/requantization-stubs.h>
17
18
xnn_qs8_requantize_fp32__scalar_lrintf(size_t n,const int32_t * input,float scale,int8_t zero_point,int8_t qmin,int8_t qmax,int8_t * output)19 void xnn_qs8_requantize_fp32__scalar_lrintf(
20 size_t n,
21 const int32_t* input,
22 float scale,
23 int8_t zero_point,
24 int8_t qmin,
25 int8_t qmax,
26 int8_t* output)
27 {
28 assert(n % 4 == 0);
29 assert(scale < 1.0f);
30 assert(scale >= 0x1.0p-32f);
31
32 const long lmin = (long) ((int32_t) qmin - (int32_t) zero_point);
33 const long lmax = (long) ((int32_t) qmax - (int32_t) zero_point);
34 for (; n != 0; n -= 4) {
35 const int32_t x = input[0];
36 const int32_t y = input[1];
37 const int32_t z = input[2];
38 const int32_t w = input[3];
39 input += 4;
40
41 const float x_scaled = (float) x * scale;
42 const float y_scaled = (float) y * scale;
43 const float z_scaled = (float) z * scale;
44 const float w_scaled = (float) w * scale;
45
46 const long x_rounded = lrintf(x_scaled);
47 const long y_rounded = lrintf(y_scaled);
48 const long z_rounded = lrintf(z_scaled);
49 const long w_rounded = lrintf(w_scaled);
50
51 const int32_t x_clamped = (int32_t) (x_rounded < lmin ? lmin : x_rounded > lmax ? lmax : x_rounded);
52 const int32_t y_clamped = (int32_t) (y_rounded < lmin ? lmin : y_rounded > lmax ? lmax : y_rounded);
53 const int32_t z_clamped = (int32_t) (z_rounded < lmin ? lmin : z_rounded > lmax ? lmax : z_rounded);
54 const int32_t w_clamped = (int32_t) (w_rounded < lmin ? lmin : w_rounded > lmax ? lmax : w_rounded);
55
56 const int32_t x_biased = x_clamped + (int32_t) zero_point;
57 const int32_t y_biased = y_clamped + (int32_t) zero_point;
58 const int32_t z_biased = z_clamped + (int32_t) zero_point;
59 const int32_t w_biased = w_clamped + (int32_t) zero_point;
60
61 output[0] = (int8_t) x_biased;
62 output[1] = (int8_t) y_biased;
63 output[2] = (int8_t) z_biased;
64 output[3] = (int8_t) w_biased;
65 output += 4;
66 }
67 }
68