llvm-project/flang/runtime/misc-intrinsic.cpp

85 lines
3.0 KiB
C++

//===-- runtime/misc-intrinsic.cpp ----------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
#include "flang/Runtime/misc-intrinsic.h"
#include "terminator.h"
#include "flang/Runtime/descriptor.h"
#include <algorithm>
#include <cstring>
#include <optional>
namespace Fortran::runtime {
static void TransferImpl(Descriptor &result, const Descriptor &source,
const Descriptor &mold, const char *sourceFile, int line,
std::optional<std::int64_t> resultExtent) {
int rank{resultExtent.has_value() ? 1 : 0};
std::size_t elementBytes{mold.ElementBytes()};
result.Establish(mold.type(), elementBytes, nullptr, rank, nullptr,
CFI_attribute_allocatable, mold.Addendum() != nullptr);
if (resultExtent) {
result.GetDimension(0).SetBounds(1, *resultExtent);
}
if (const DescriptorAddendum * addendum{mold.Addendum()}) {
*result.Addendum() = *addendum;
}
if (int stat{result.Allocate()}) {
Terminator{sourceFile, line}.Crash(
"TRANSFER: could not allocate memory for result; STAT=%d", stat);
}
char *to{result.OffsetElement<char>()};
std::size_t resultBytes{result.Elements() * result.ElementBytes()};
const std::size_t sourceElementBytes{source.ElementBytes()};
std::size_t sourceElements{source.Elements()};
SubscriptValue sourceAt[maxRank];
source.GetLowerBounds(sourceAt);
while (resultBytes > 0 && sourceElements > 0) {
std::size_t toMove{std::min(resultBytes, sourceElementBytes)};
std::memcpy(to, source.Element<char>(sourceAt), toMove);
to += toMove;
resultBytes -= toMove;
--sourceElements;
source.IncrementSubscripts(sourceAt);
}
if (resultBytes > 0) {
std::memset(to, 0, resultBytes);
}
}
extern "C" {
void RTNAME(Transfer)(Descriptor &result, const Descriptor &source,
const Descriptor &mold, const char *sourceFile, int line) {
std::optional<std::int64_t> elements;
if (mold.rank() > 0) {
if (std::size_t sourceElementBytes{
source.Elements() * source.ElementBytes()}) {
if (std::size_t moldElementBytes{mold.ElementBytes()}) {
elements = static_cast<std::int64_t>(
(sourceElementBytes + moldElementBytes - 1) / moldElementBytes);
} else {
Terminator{sourceFile, line}.Crash("TRANSFER: zero-sized type of MOLD= "
"when SOURCE= is not zero-sized");
}
} else {
elements = 0;
}
}
return TransferImpl(
result, source, mold, sourceFile, line, std::move(elements));
}
void RTNAME(TransferSize)(Descriptor &result, const Descriptor &source,
const Descriptor &mold, const char *sourceFile, int line,
std::int64_t size) {
return TransferImpl(result, source, mold, sourceFile, line, size);
}
} // extern "C"
} // namespace Fortran::runtime