xref: /aosp_15_r20/external/XNNPACK/src/f32-f16-vcvt/gen/vcvt-scalar-bitcast-x2.c (revision 4bdc94577ba0e567308109d787f7fec7b531ce36)
1 // Auto-generated file. Do not edit!
2 //   Template: src/f32-f16-vcvt/scalar-bitcast.c.in
3 //   Generator: tools/xngen
4 //
5 // Copyright 2021 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 <xnnpack/common.h>
13 #include <xnnpack/math.h>
14 #include <xnnpack/vcvt.h>
15 
16 
xnn_f32_f16_vcvt_ukernel__scalar_bitcast_x2(size_t n,const float * input,void * output,const union xnn_f32_f16_cvt_params params[restrict XNN_MIN_ELEMENTS (1)])17 void xnn_f32_f16_vcvt_ukernel__scalar_bitcast_x2(
18     size_t n,
19     const float* input,
20     void* output,
21     const union xnn_f32_f16_cvt_params params[restrict XNN_MIN_ELEMENTS(1)])
22 {
23   assert(n != 0);
24   assert(n % sizeof(float) == 0);
25   assert(input != NULL);
26   assert(output != NULL);
27 
28   const uint32_t vnonsign_mask = params->scalar_bitcast.nonsign_mask;
29   const uint32_t vexp_bias = params->scalar_bitcast.exp_bias;
30   const float vscale_to_inf = params->scalar_bitcast.scale_to_inf;
31   const uint32_t vexpw_max = params->scalar_bitcast.expw_max;
32   const float vscale_to_zero = params->scalar_bitcast.scale_to_zero;
33   const uint32_t vbias_min = params->scalar_bitcast.bias_min;
34   const uint16_t vexph_mask = params->scalar_bitcast.exph_mask;
35   const uint16_t vmanth_mask = params->scalar_bitcast.manth_mask;
36   const uint16_t vnanh = params->scalar_bitcast.nanh;
37 
38   const uint32_t* i = (const uint32_t*) input;
39   uint16_t* o = (uint16_t*) output;
40   for (; n >= 2 * sizeof(float); n -= 2 * sizeof(float)) {
41     const uint32_t vw0 = i[0];
42     const uint32_t vw1 = i[1];
43     i += 2;
44 
45     const uint32_t vnonsignw0 = vw0 & vnonsign_mask;
46     const uint32_t vnonsignw1 = vw1 & vnonsign_mask;
47 
48     float vf0 = uint32_as_float(vnonsignw0);
49     float vf1 = uint32_as_float(vnonsignw1);
50     const uint32_t vsignw0 = vw0 ^ vnonsignw0;
51     const uint32_t vsignw1 = vw1 ^ vnonsignw1;
52     uint32_t vbias0 = vnonsignw0 + vexp_bias;
53     uint32_t vbias1 = vnonsignw1 + vexp_bias;
54 
55     vf0 *= vscale_to_inf;
56     vf1 *= vscale_to_inf;
57     vbias0 &= vexpw_max;
58     vbias1 &= vexpw_max;
59 
60     vf0 *= vscale_to_zero;
61     vf1 *= vscale_to_zero;
62     vbias0 = math_max_u32(vbias0, vbias_min);
63     vbias1 = math_max_u32(vbias1, vbias_min);
64 
65     vf0 += uint32_as_float(vbias0);
66     vf1 += uint32_as_float(vbias1);
67 
68     const uint32_t vbits0 = float_as_uint32(vf0);
69     const uint32_t vbits1 = float_as_uint32(vf1);
70 
71     const uint16_t vexph0 = (uint16_t) (vbits0 >> 13) & vexph_mask;
72     const uint16_t vexph1 = (uint16_t) (vbits1 >> 13) & vexph_mask;
73     const uint16_t vmanth0 = (uint16_t) vbits0 & vmanth_mask;
74     const uint16_t vmanth1 = (uint16_t) vbits1 & vmanth_mask;
75     const uint16_t vsignh0 = (uint16_t) (vsignw0 >> 16);
76     const uint16_t vsignh1 = (uint16_t) (vsignw1 >> 16);
77 
78     uint16_t vh0 = vexph0 + vmanth0;
79     uint16_t vh1 = vexph1 + vmanth1;
80     if XNN_UNPREDICTABLE(vnonsignw0 > vexpw_max) {
81       vh0 = vnanh;
82     }
83     if XNN_UNPREDICTABLE(vnonsignw1 > vexpw_max) {
84       vh1 = vnanh;
85     }
86     vh0 |= vsignh0;
87     vh1 |= vsignh1;
88 
89     o[0] = vh0;
90     o[1] = vh1;
91     o += 2;
92   }
93   if XNN_UNLIKELY(n != 0) {
94     const uint32_t vw = *i;
95 
96     const uint32_t vnonsignw = vw & vnonsign_mask;
97 
98     float vf = uint32_as_float(vnonsignw);
99     const uint32_t vsignw = vw ^ vnonsignw;
100     uint32_t vbias = vnonsignw + vexp_bias;
101 
102     vf *= vscale_to_inf;
103     vbias &= vexpw_max;
104 
105     vf *= vscale_to_zero;
106     vbias = math_max_u32(vbias, vbias_min);
107 
108     vf += uint32_as_float(vbias);
109 
110     const uint32_t vbits = float_as_uint32(vf);
111 
112     const uint16_t vexph = (uint16_t) (vbits >> 13) & vexph_mask;
113     const uint16_t vmanth = (uint16_t) vbits & vmanth_mask;
114     const uint16_t vsignh = (uint16_t) (vsignw >> 16);
115 
116     uint16_t vh = vexph + vmanth;
117     if XNN_UNPREDICTABLE(vnonsignw > vexpw_max) {
118       vh = vnanh;
119     }
120     vh |= vsignh;
121 
122     *o = vh;
123   }
124 }
125