flang/runtime/copy.cpp

   1 //===-- runtime/copy.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 "copy.h"
  10 #include "terminator.h"
  11 #include "type-info.h"
  12 #include "flang/Runtime/allocatable.h"
  13 #include "flang/Runtime/descriptor.h"
  14 #include <cstring>
  15
  16 namespace Fortran::runtime {
  17
  18 void CopyElement(const Descriptor &to, const SubscriptValue toAt[],
  19     const Descriptor &from, const SubscriptValue fromAt[],
  20     Terminator &terminator) {
  21   char *toPtr{to.Element<char>(toAt)};
  22   const char *fromPtr{from.Element<const char>(fromAt)};
  23   RUNTIME_CHECK(terminator, to.ElementBytes() == from.ElementBytes());
  24   std::memcpy(toPtr, fromPtr, to.ElementBytes());
  25   if (const auto *addendum{to.Addendum()}) {
  26     if (const auto *derived{addendum->derivedType()}) {
  27       RUNTIME_CHECK(terminator,
  28           from.Addendum() && derived == from.Addendum()->derivedType());
  29       const Descriptor &componentDesc{derived->component()};
  30       const typeInfo::Component *component{
  31           componentDesc.OffsetElement<typeInfo::Component>()};
  32       std::size_t nComponents{componentDesc.Elements()};
  33       for (std::size_t j{0}; j < nComponents; ++j, ++component) {
  34         if (component->genre() == typeInfo::Component::Genre::Allocatable ||
  35             component->genre() == typeInfo::Component::Genre::Automatic) {
  36           Descriptor &toDesc{
  37               *reinterpret_cast<Descriptor *>(toPtr + component->offset())};
  38           if (toDesc.raw().base_addr != nullptr) {
  39             toDesc.set_base_addr(nullptr);
  40             RUNTIME_CHECK(terminator, toDesc.Allocate() == CFI_SUCCESS);
  41             const Descriptor &fromDesc{*reinterpret_cast<const Descriptor *>(
  42                 fromPtr + component->offset())};
  43             CopyArray(toDesc, fromDesc, terminator);
  44           }
  45         }
  46       }
  47     }
  48   }
  49 }
  50
  51 void CopyArray(
  52     const Descriptor &to, const Descriptor &from, Terminator &terminator) {
  53   std::size_t elements{to.Elements()};
  54   RUNTIME_CHECK(terminator, elements == from.Elements());
  55   SubscriptValue toAt[maxRank], fromAt[maxRank];
  56   to.GetLowerBounds(toAt);
  57   from.GetLowerBounds(fromAt);
  58   while (elements-- > 0) {
  59     CopyElement(to, toAt, from, fromAt, terminator);
  60     to.IncrementSubscripts(toAt);
  61     from.IncrementSubscripts(fromAt);
  62   }
  63 }
  64 } // namespace Fortran::runtime