1//===-- runtime/misc-intrinsic.cpp ----------------------------------------===//
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#include "flang/Runtime/misc-intrinsic.h"
10#include "terminator.h"
11#include "tools.h"
12#include "flang/Runtime/descriptor.h"
13#include <algorithm>
14#include <cstring>
15#include <optional>
16
17namespace Fortran::runtime {
18
19static RT_API_ATTRS void TransferImpl(Descriptor &result,
20 const Descriptor &source, const Descriptor &mold, const char *sourceFile,
21 int line, std::optional<std::int64_t> resultExtent) {
22 int rank{resultExtent.has_value() ? 1 : 0};
23 std::size_t elementBytes{mold.ElementBytes()};
24 result.Establish(mold.type(), elementBytes, nullptr, rank, nullptr,
25 CFI_attribute_allocatable, mold.Addendum() != nullptr);
26 if (resultExtent) {
27 result.GetDimension(0).SetBounds(1, *resultExtent);
28 }
29 if (const DescriptorAddendum * addendum{mold.Addendum()}) {
30 *result.Addendum() = *addendum;
31 }
32 if (int stat{result.Allocate()}) {
33 Terminator{sourceFile, line}.Crash(
34 "TRANSFER: could not allocate memory for result; STAT=%d", stat);
35 }
36 char *to{result.OffsetElement<char>()};
37 std::size_t resultBytes{result.Elements() * result.ElementBytes()};
38 const std::size_t sourceElementBytes{source.ElementBytes()};
39 std::size_t sourceElements{source.Elements()};
40 SubscriptValue sourceAt[maxRank];
41 source.GetLowerBounds(sourceAt);
42 while (resultBytes > 0 && sourceElements > 0) {
43 std::size_t toMove{std::min(a: resultBytes, b: sourceElementBytes)};
44 std::memcpy(dest: to, src: source.Element<char>(sourceAt), n: toMove);
45 to += toMove;
46 resultBytes -= toMove;
47 --sourceElements;
48 source.IncrementSubscripts(sourceAt);
49 }
50 if (resultBytes > 0) {
51 std::memset(s: to, c: 0, n: resultBytes);
52 }
53}
54
55extern "C" {
56RT_EXT_API_GROUP_BEGIN
57
58void RTDEF(Transfer)(Descriptor &result, const Descriptor &source,
59 const Descriptor &mold, const char *sourceFile, int line) {
60 std::optional<std::int64_t> elements;
61 if (mold.rank() > 0) {
62 if (std::size_t sourceElementBytes{
63 source.Elements() * source.ElementBytes()}) {
64 if (std::size_t moldElementBytes{mold.ElementBytes()}) {
65 elements = static_cast<std::int64_t>(
66 (sourceElementBytes + moldElementBytes - 1) / moldElementBytes);
67 } else {
68 Terminator{sourceFile, line}.Crash("TRANSFER: zero-sized type of MOLD= "
69 "when SOURCE= is not zero-sized");
70 }
71 } else {
72 elements = std::int64_t{0};
73 }
74 }
75 return TransferImpl(
76 result, source, mold, sourceFile, line, std::move(elements));
77}
78
79void RTDEF(TransferSize)(Descriptor &result, const Descriptor &source,
80 const Descriptor &mold, const char *sourceFile, int line,
81 std::int64_t size) {
82 return TransferImpl(result, source, mold, sourceFile, line, size);
83}
84
85RT_EXT_API_GROUP_END
86} // extern "C"
87} // namespace Fortran::runtime
88

source code of flang/runtime/misc-intrinsic.cpp