| 1 | //===-- lib/floatunsitf.c - uint -> quad-precision conversion -----*- C -*-===// |
|---|
| 2 | // |
|---|
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
|---|
| 4 | // See https://llvm.org/LICENSE.txt for license information. |
|---|
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
|---|
| 6 | // |
|---|
| 7 | //===----------------------------------------------------------------------===// |
|---|
| 8 | // |
|---|
| 9 | // This file implements unsigned integer to quad-precision conversion for the |
|---|
| 10 | // compiler-rt library in the IEEE-754 default round-to-nearest, ties-to-even |
|---|
| 11 | // mode. |
|---|
| 12 | // |
|---|
| 13 | //===----------------------------------------------------------------------===// |
|---|
| 14 | |
|---|
| 15 | #define QUAD_PRECISION |
|---|
| 16 | #include "fp_lib.h" |
|---|
| 17 | |
|---|
| 18 | #if defined(CRT_HAS_TF_MODE) |
|---|
| 19 | COMPILER_RT_ABI fp_t __floatunsitf(su_int a) { |
|---|
| 20 | |
|---|
| 21 | const int aWidth = sizeof a * CHAR_BIT; |
|---|
| 22 | |
|---|
| 23 | // Handle zero as a special case to protect clz |
|---|
| 24 | if (a == 0) |
|---|
| 25 | return fromRep(x: 0); |
|---|
| 26 | |
|---|
| 27 | // Exponent of (fp_t)a is the width of abs(a). |
|---|
| 28 | const int exponent = (aWidth - 1) - clzsi(a); |
|---|
| 29 | rep_t result; |
|---|
| 30 | |
|---|
| 31 | // Shift a into the significand field and clear the implicit bit. |
|---|
| 32 | const int shift = significandBits - exponent; |
|---|
| 33 | result = (rep_t)a << shift ^ implicitBit; |
|---|
| 34 | |
|---|
| 35 | // Insert the exponent |
|---|
| 36 | result += (rep_t)(exponent + exponentBias) << significandBits; |
|---|
| 37 | return fromRep(x: result); |
|---|
| 38 | } |
|---|
| 39 | |
|---|
| 40 | #endif |
|---|
| 41 | |
|---|
