1// Copyright 2015, ARM Limited
2// All rights reserved.
3//
4// Redistribution and use in source and binary forms, with or without
5// modification, are permitted provided that the following conditions are met:
6//
7//   * Redistributions of source code must retain the above copyright notice,
8//     this list of conditions and the following disclaimer.
9//   * Redistributions in binary form must reproduce the above copyright notice,
10//     this list of conditions and the following disclaimer in the documentation
11//     and/or other materials provided with the distribution.
12//   * Neither the name of ARM Limited nor the names of its contributors may be
13//     used to endorse or promote products derived from this software without
14//     specific prior written permission.
15//
16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS CONTRIBUTORS "AS IS" AND
17// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
20// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
23// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
25// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26
27#include "vixl/utils.h"
28#include <stdio.h>
29
30namespace vixl {
31
32uint32_t float_to_rawbits(float value) {
33  uint32_t bits = 0;
34  memcpy(&bits, &value, 4);
35  return bits;
36}
37
38
39uint64_t double_to_rawbits(double value) {
40  uint64_t bits = 0;
41  memcpy(&bits, &value, 8);
42  return bits;
43}
44
45
46float rawbits_to_float(uint32_t bits) {
47  float value = 0.0;
48  memcpy(&value, &bits, 4);
49  return value;
50}
51
52
53double rawbits_to_double(uint64_t bits) {
54  double value = 0.0;
55  memcpy(&value, &bits, 8);
56  return value;
57}
58
59
60uint32_t float_sign(float val) {
61  uint32_t rawbits = float_to_rawbits(val);
62  return unsigned_bitextract_32(31, 31, rawbits);
63}
64
65
66uint32_t float_exp(float val) {
67  uint32_t rawbits = float_to_rawbits(val);
68  return unsigned_bitextract_32(30, 23, rawbits);
69}
70
71
72uint32_t float_mantissa(float val) {
73  uint32_t rawbits = float_to_rawbits(val);
74  return unsigned_bitextract_32(22, 0, rawbits);
75}
76
77
78uint32_t double_sign(double val) {
79  uint64_t rawbits = double_to_rawbits(val);
80  return static_cast<uint32_t>(unsigned_bitextract_64(63, 63, rawbits));
81}
82
83
84uint32_t double_exp(double val) {
85  uint64_t rawbits = double_to_rawbits(val);
86  return static_cast<uint32_t>(unsigned_bitextract_64(62, 52, rawbits));
87}
88
89
90uint64_t double_mantissa(double val) {
91  uint64_t rawbits = double_to_rawbits(val);
92  return unsigned_bitextract_64(51, 0, rawbits);
93}
94
95
96float float_pack(uint32_t sign, uint32_t exp, uint32_t mantissa) {
97  uint64_t bits = (sign << 31) | (exp << 23) | mantissa;
98  return rawbits_to_float(bits);
99}
100
101
102double double_pack(uint64_t sign, uint64_t exp, uint64_t mantissa) {
103  uint64_t bits = (sign << 63) | (exp << 52) | mantissa;
104  return rawbits_to_double(bits);
105}
106
107
108int float16classify(float16 value) {
109  uint16_t exponent_max = (1 << 5) - 1;
110  uint16_t exponent_mask = exponent_max << 10;
111  uint16_t mantissa_mask = (1 << 10) - 1;
112
113  uint16_t exponent = (value & exponent_mask) >> 10;
114  uint16_t mantissa = value & mantissa_mask;
115  if (exponent == 0) {
116    if (mantissa == 0) {
117      return FP_ZERO;
118    }
119    return FP_SUBNORMAL;
120  } else if (exponent == exponent_max) {
121    if (mantissa == 0) {
122      return FP_INFINITE;
123    }
124    return FP_NAN;
125  }
126  return FP_NORMAL;
127}
128
129
130unsigned CountClearHalfWords(uint64_t imm, unsigned reg_size) {
131  VIXL_ASSERT((reg_size % 8) == 0);
132  int count = 0;
133  for (unsigned i = 0; i < (reg_size / 16); i++) {
134    if ((imm & 0xffff) == 0) {
135      count++;
136    }
137    imm >>= 16;
138  }
139  return count;
140}
141
142}  // namespace vixl
143