xref: /aosp_15_r20/external/XNNPACK/src/f16-f32-vcvt/scalar.c.in (revision 4bdc94577ba0e567308109d787f7fec7b531ce36)
1// Copyright 2021 Google LLC
2//
3// This source code is licensed under the BSD-style license found in the
4// LICENSE file in the root directory of this source tree.
5
6$assert BATCH_TILE >= 1
7$ABC = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
8#include <assert.h>
9
10#include <xnnpack/common.h>
11#include <xnnpack/math.h>
12#include <xnnpack/vcvt.h>
13
14
15void xnn_f16_f32_vcvt_ukernel__scalar_x${BATCH_TILE}(
16    size_t n,
17    const void* input,
18    float* output,
19    const union xnn_f16_f32_cvt_params params[restrict XNN_MIN_ELEMENTS(1)])
20{
21  assert(n != 0);
22  assert(n % sizeof(uint16_t) == 0);
23  assert(input != NULL);
24  assert(output != NULL);
25
26  const uint32_t vsign_mask = params->scalar.sign_mask;
27  const uint32_t vexp_offset = params->scalar.exp_offset;
28  const float vexp_scale = params->scalar.exp_scale;
29  const uint32_t vmagic_mask = params->scalar.magic_mask;
30  const float vmagic_bias = params->scalar.magic_bias;
31  const uint32_t vdenorm_cutoff = params->scalar.denorm_cutoff;
32
33  const uint16_t* i = (const uint16_t*) input;
34  uint32_t* o = (uint32_t*) output;
35  $if BATCH_TILE > 1:
36    for (; n >= ${BATCH_TILE} * sizeof(uint16_t); n -= ${BATCH_TILE} * sizeof(uint16_t)) {
37      $for N in range(BATCH_TILE):
38        const uint16_t vh${N} = i[${N}];
39      i += ${BATCH_TILE};
40
41      $for N in range(BATCH_TILE):
42        const uint32_t vw${N} = (uint32_t) vh${N} << 16;
43
44      $for N in range(BATCH_TILE):
45        const uint32_t vsign${N} = vw${N} & vsign_mask;
46
47      $for N in range(BATCH_TILE):
48        const uint32_t v2w${N} = vw${N} + vw${N};
49
50      $for N in range(BATCH_TILE):
51        const uint32_t vnorm${N} = float_as_uint32(uint32_as_float((v2w${N} >> 4) + vexp_offset) * vexp_scale);
52
53      $for N in range(BATCH_TILE):
54        const uint32_t vdenorm${N} = float_as_uint32(uint32_as_float((v2w${N} >> 17) | vmagic_mask) - vmagic_bias);
55
56      $for N in range(BATCH_TILE):
57        const uint32_t vf${N} = vsign${N} | (XNN_UNPREDICTABLE(v2w${N} < vdenorm_cutoff) ? vdenorm${N} : vnorm${N});
58
59      $for N in range(BATCH_TILE):
60        o[${N}] = vf${N};
61      o += ${BATCH_TILE};
62    }
63  $if BATCH_TILE == 1:
64    do {
65      const uint16_t vh = *i++;
66
67      const uint32_t vw = (uint32_t) vh << 16;
68      const uint32_t vsign = vw & vsign_mask;
69      const uint32_t v2w = vw + vw;
70      const uint32_t vnorm = float_as_uint32(uint32_as_float((v2w >> 4) + vexp_offset) * vexp_scale);
71      const uint32_t vdenorm = float_as_uint32(uint32_as_float((v2w >> 17) | vmagic_mask) - vmagic_bias);
72      const uint32_t vf = vsign | (XNN_UNPREDICTABLE(v2w < vdenorm_cutoff) ? vdenorm : vnorm);
73
74      *o++ = vf;
75
76      n -= sizeof(uint16_t);
77    } while (n != 0);
78  $elif BATCH_TILE == 2:
79    if XNN_UNLIKELY(n != 0) {
80      const uint16_t vh = *i;
81
82      const uint32_t vw = (uint32_t) vh << 16;
83      const uint32_t vsign = vw & vsign_mask;
84      const uint32_t v2w = vw + vw;
85      const uint32_t vnorm = float_as_uint32(uint32_as_float((v2w >> 4) + vexp_offset) * vexp_scale);
86      const uint32_t vdenorm = float_as_uint32(uint32_as_float((v2w >> 17) | vmagic_mask) - vmagic_bias);
87      const uint32_t vf = vsign | (XNN_UNPREDICTABLE(v2w < vdenorm_cutoff) ? vdenorm : vnorm);
88
89      *o = vf;
90    }
91  $else:
92    if XNN_UNLIKELY(n != 0) {
93      do {
94        const uint16_t vh = *i++;
95
96        const uint32_t vw = (uint32_t) vh << 16;
97        const uint32_t vsign = vw & vsign_mask;
98        const uint32_t v2w = vw + vw;
99        const uint32_t vnorm = float_as_uint32(uint32_as_float((v2w >> 4) + vexp_offset) * vexp_scale);
100        const uint32_t vdenorm = float_as_uint32(uint32_as_float((v2w >> 17) | vmagic_mask) - vmagic_bias);
101        const uint32_t vf = vsign | (XNN_UNPREDICTABLE(v2w < vdenorm_cutoff) ? vdenorm : vnorm);
102
103        *o++ = vf;
104
105        n -= sizeof(uint16_t);
106      } while (n != 0);
107    }
108}
109