blob: c01f81e41e8eaa166b9a06bedd02534d62bf46a0 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
|
//===-- lib/floatsisf.c - integer -> single-precision conversion --*- C -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements integer to single-precision conversion for the
// compiler-rt library in the IEEE-754 default round-to-nearest, ties-to-even
// mode.
//
//===----------------------------------------------------------------------===//
#define SINGLE_PRECISION
#include "fp_lib.h"
#include "int_lib.h"
COMPILER_RT_ABI fp_t __floatsisf(si_int a) {
const int aWidth = sizeof a * CHAR_BIT;
// Handle zero as a special case to protect clz
if (a == 0)
return fromRep(0);
// All other cases begin by extracting the sign and absolute value of a
rep_t sign = 0;
if (a < 0) {
sign = signBit;
a = -a;
}
// Exponent of (fp_t)a is the width of abs(a).
const int exponent = (aWidth - 1) - clzsi(a);
rep_t result;
// Shift a into the significand field, rounding if it is a right-shift
if (exponent <= significandBits) {
const int shift = significandBits - exponent;
result = (rep_t)a << shift ^ implicitBit;
} else {
const int shift = exponent - significandBits;
result = (rep_t)a >> shift ^ implicitBit;
rep_t round = (rep_t)a << (typeWidth - shift);
if (round > signBit)
result++;
if (round == signBit)
result += result & 1;
}
// Insert the exponent
result += (rep_t)(exponent + exponentBias) << significandBits;
// Insert the sign bit and return
return fromRep(result | sign);
}
#if defined(__ARM_EABI__)
#if defined(COMPILER_RT_ARMHF_TARGET)
AEABI_RTABI fp_t __aeabi_i2f(int a) { return __floatsisf(a); }
#else
COMPILER_RT_ALIAS(__floatsisf, __aeabi_i2f)
#endif
#endif
|
