tagTapeBase.hpp

/*
 * CoDiPack, a Code Differentiation Package
 *
 * Copyright (C) 2015-2026 Chair for Scientific Computing (SciComp), University of Kaiserslautern-Landau
 * Homepage: http://scicomp.rptu.de
 * Contact:  Prof. Nicolas R. Gauger (codi@scicomp.uni-kl.de)
 *
 * Lead developers: Max Sagebaum, Johannes Blühdorn (SciComp, University of Kaiserslautern-Landau)
 *
 * This file is part of CoDiPack (http://scicomp.rptu.de/software/codi).
 *
 * CoDiPack is free software: you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * CoDiPack is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * See the GNU General Public License for more details.
 * You should have received a copy of the GNU
 * General Public License along with CoDiPack.
 * If not, see <http://www.gnu.org/licenses/>.
 *
 * For other licensing options please contact us.
 *
 * Authors:
 *  - SciComp, University of Kaiserslautern-Landau:
 *    - Max Sagebaum
 *    - Johannes Blühdorn
 *    - Former members:
 *      - Tim Albring
 */
#pragma once
 
#include "../../expressions/logic/helpers/forEachLeafLogic.hpp"
#include "../../misc/enumBitset.hpp"
#include "../indices/indexManagerInterface.hpp"
#include "../interfaces/fullTapeInterface.hpp"
#include "../misc/adjointVectorAccess.hpp"
#include "tagData.hpp"

namespace codi {

  template<typename Real, typename Tag>
  struct ValidationIndicator {
      bool isActive;     
      bool hasError;     
      bool hasTagError;  
      bool hasUseError;  
      Tag errorTag;      
      Real value;        

      ValidationIndicator()
          : isActive(false), hasError(false), hasTagError(false), hasUseError(false), errorTag(), value() {}
  };

  template<typename T_Real, typename T_Tag, typename T_Gradient, typename T_Impl>
  struct TagTapeBase {
      using Real = CODI_DD(T_Real, double);       
      using Tag = CODI_DD(T_Tag, int);            
      using Gradient = CODI_DD(T_Gradient, int);  
      using Impl = CODI_DD(T_Impl, int);          
 
      using Identifier = int;                   
      using ActiveTypeTapeData = TagData<Tag>;  

      using TagPropertyErrorCallback = void (*)(Real const& currentValue, Real const& newValue, TagFlags flag,
                                                void* userData);

      using TagErrorCallback = void (*)(Tag const& correctTag, Tag const& wrongTag, void* userData);
 
      static Tag constexpr PassiveTag = Tag(0);   
      static Tag constexpr InvalidTag = Tag(-1);  
 
    protected:
 
      Tag curTag;  
 
      TagPropertyErrorCallback tagPropertyErrorCallback;  
      void* tagPropertyErrorUserData;                     
 
      TagErrorCallback tagErrorCallback;  
      void* tagErrorUserData;             
 
      bool preaccumulationHandling;  
      Tag preaccumulationTag;        
 
      Identifier tempIdentifier = 0;           
      Identifier const activeIdentifier = 1;   
      Identifier const passiveIdentifier = 0;  
 
    public:

      TagTapeBase()
          : curTag(),
            tagPropertyErrorCallback(defaultPropertyErrorCallback),
            tagPropertyErrorUserData(nullptr),
            tagErrorCallback(defaultTagErrorCallback),
            tagErrorUserData(this),
            preaccumulationHandling(true),
            preaccumulationTag(1337) {}

      struct ValidateTags : public ForEachLeafLogic<ValidateTags> {
        public:

          template<typename Node>
          CODI_INLINE void handleActive(Node const& node, ValidationIndicator<Real, Tag>& vi, Impl& tape) {
            ActiveTypeTapeData tagData = node.getTapeData();
            tape.verifyTag(vi, tagData.tag);
            tape.verifyProperties(vi, node.getValue(), tagData.properties);
          }
      };

      void swap(Impl& other) {
        std::swap(curTag, other.curTag);
        std::swap(tagPropertyErrorCallback, other.tagPropertyErrorCallback);
        std::swap(tagPropertyErrorUserData, other.tagPropertyErrorUserData);
        std::swap(tagErrorCallback, other.tagErrorCallback);
        std::swap(tagErrorUserData, other.tagErrorUserData);
        std::swap(preaccumulationHandling, other.preaccumulationHandling);
        std::swap(preaccumulationTag, other.preaccumulationTag);
      }
 
      /*******************************************************************************/

      CODI_INLINE Identifier const& getIdentifier(ActiveTypeTapeData const& data) {
        if (data.tag != 0) {
          return activeIdentifier;
        } else {
          return passiveIdentifier;
        }
      }

      CODI_INLINE Identifier& getIdentifier(ActiveTypeTapeData& data) {
        tempIdentifier = getIdentifier(std::as_const(data));
        return tempIdentifier;
      }

      /*******************************************************************************/
 
      static bool constexpr AllowJacobianOptimization = false;  

      template<typename Real>
      void initTapeData(Real& value, ActiveTypeTapeData& data) {
        CODI_UNUSED(value);
        data = ActiveTypeTapeData();
      }

      template<typename Real>
      void destroyTapeData(Real& value, ActiveTypeTapeData& data) {
        CODI_UNUSED(value, data);
      }
 
      template<typename Aggregated, typename Type, typename Lhs, typename Rhs>
      CODI_INLINE void store(AggregatedActiveType<Aggregated, Type, Lhs>& lhs,
                             ExpressionInterface<Aggregated, Rhs> const& rhs) {
        using AggregatedTraits = RealTraits::AggregatedTypeTraits<Aggregated>;
 
        int constexpr Elements = AggregatedTraits::Elements;
 
        ValidationIndicator<Real, Tag> vi[Elements];
 
        Aggregated real = rhs.cast().getValue();
 
        static_for<Elements>([this, &vi, &lhs, &rhs, &real](auto i) CODI_LAMBDA_INLINE {
          ValidateTags validate;
 
          validate.eval(ArrayAccessExpression<Aggregated, i.value, Rhs>(rhs), vi[i.value], cast());
          checkLhsError(lhs.values[i.value], AggregatedTraits::template arrayAccess<i.value>(real));
 
          handleError(vi[i.value]);
        });
 
        static_for<Elements>([this, &vi, &lhs, &real](auto i) CODI_LAMBDA_INLINE {
          if (vi[i.value].isActive) {
            setTag(lhs.values[i.value].getTapeData().tag);
          } else {
            resetTag(lhs.values[i.value].getTapeData().tag);
          }
          lhs.values[i.value].value() = AggregatedTraits::template arrayAccess<i.value>(real);
        });
      }

      template<typename Aggregated, typename Type, typename Lhs, typename Rhs>
      CODI_INLINE void store(AggregatedActiveType<Aggregated, Type, Lhs>& lhs,
                             AggregatedActiveType<Aggregated, Type, Rhs> const& rhs) {
        store<Aggregated, Type, Lhs, Rhs>(lhs, static_cast<ExpressionInterface<Aggregated, Rhs> const&>(rhs));
      }

      template<typename Lhs, typename Rhs>
      void store(LhsExpressionInterface<Real, Gradient, Impl, Lhs>& lhs, ExpressionInterface<Real, Rhs> const& rhs) {
        ValidateTags validate;
        ValidationIndicator<Real, Tag> vi;
 
        validate.eval(rhs, vi, cast());
 
        checkLhsError(lhs, rhs.cast().getValue());
 
        handleError(vi);
 
        if (vi.isActive) {
          setTag(lhs.cast().getTapeData().tag);
        } else {
          resetTag(lhs.cast().getTapeData().tag);
        }
 
        lhs.cast().value() = rhs.cast().getValue();
      }

      template<typename Lhs, typename Rhs>
      void store(LhsExpressionInterface<Real, Gradient, Impl, Lhs>& lhs,
                 LhsExpressionInterface<Real, Gradient, Impl, Rhs> const& rhs) {
        store<Lhs, Rhs>(lhs, static_cast<ExpressionInterface<Real, Rhs> const&>(rhs));
      }

      template<typename Lhs>
      void store(LhsExpressionInterface<Real, Gradient, Impl, Lhs>& lhs, Real const& rhs) {
        checkLhsError(lhs, rhs);
 
        resetTag(lhs.cast().getTapeData().tag);
 
        lhs.cast().value() = rhs;
      }

      /*******************************************************************************/

      void setCurTag(const Tag& tag) {
        this->curTag = tag;
      }

      Tag getCurTag() {
        return this->curTag;
      }

      template<typename Lhs>
      Tag getTagFromVariable(LhsExpressionInterface<Real, Gradient, Impl, Lhs>& value) {
        return value.cast().getTapeData().tag;
      }

      template<typename Lhs>
      void setTagOnVariable(LhsExpressionInterface<Real, Gradient, Impl, Lhs> const& value) {
        value.cast().getTapeData().tag = this->curTag;
      }

      template<typename Lhs>
      void clearTagOnVariable(LhsExpressionInterface<Real, Gradient, Impl, Lhs>& value) {
        value.cast().getTapeData().tag = Tag();
      }

      template<typename Lhs>
      void clearTagPropertiesOnVariable(LhsExpressionInterface<Real, Gradient, Impl, Lhs>& value) {
        value.cast().getTapeData().properties.reset();
      }

      template<typename Lhs>
      void setTagPropertyOnVariable(LhsExpressionInterface<Real, Gradient, Impl, Lhs>& value, TagFlags flag) {
        value.cast().getTapeData().properties.set(flag);
      }

      template<typename Lhs>
      bool hasTagPropertyOnVariable(LhsExpressionInterface<Real, Gradient, Impl, Lhs>& value, TagFlags flag) {
        return value.cast().getTapeData().properties.test(flag);
      }

      void setTagPropertyErrorCallback(TagPropertyErrorCallback const& callback, void* userData) {
        tagPropertyErrorCallback = callback;
        tagPropertyErrorUserData = userData;
      }

      void setTagErrorCallback(TagErrorCallback const& callback, void* userData) {
        tagErrorCallback = callback;
        tagErrorUserData = userData;
      }

      CODI_INLINE void setPreaccumulationHandlingEnabled(bool enabled) {
        preaccumulationHandling = enabled;
      }

      CODI_INLINE void setPreaccumulationHandlingTag(Tag tag) {
        preaccumulationTag = tag;
      }

      CODI_INLINE bool isPreaccumulationHandlingEnabled() {
        return preaccumulationHandling;
      }

      CODI_INLINE Tag getPreaccumulationHandlingTag() {
        return preaccumulationTag;
      }
 
    protected:

      CODI_INLINE void verifyTag(ValidationIndicator<Real, Tag>& vi, Tag const& tag) const {
        if (PassiveTag != tag && InvalidTag != tag) {
          vi.isActive = true;
          if (tag != curTag) {
            vi.hasError = true;
            vi.hasTagError = true;
            vi.errorTag = tag;
          }
        }
      }

      CODI_INLINE void verifyTag(Tag const& tag) const {
        ValidationIndicator<Real, Tag> vi;
 
        verifyTag(vi, tag);
        handleError(vi);
      }

      CODI_INLINE void verifyProperties(ValidationIndicator<Real, Tag>& vi, Real const& value,
                                        const EnumBitset<TagFlags>& properties) const {
        if (properties.test(TagFlags::DoNotUse)) {
          vi.hasError = true;
          vi.hasUseError = true;
          vi.value = value;
        }
      }

      CODI_INLINE void verifyTagAndProperties(Tag const& tag, Real const& value,
                                              const EnumBitset<TagFlags>& properties) const {
        ValidationIndicator<Real, Tag> vi;
 
        verifyTag(vi, tag);
        verifyProperties(vi, value, properties);
        handleError(vi);
      }

      static void defaultPropertyErrorCallback(Real const& currentValue, Real const& newValue, TagFlags flag,
                                               void* userData) {
        CODI_UNUSED(userData);
 
        std::cerr << "Property error '" << std::to_string(flag) << "' on value. current value: " << currentValue
                  << " new value: " << newValue << "" << std::endl;
      }

      static void defaultTagErrorCallback(Tag const& correctTag, Tag const& wrongTag, void* userData) {
        TagTapeBase& impl = *static_cast<TagTapeBase*>(userData);
 
        // output default warning if no handle is defined.
        std::cerr << "Use of variable with bad tag '" << wrongTag << "', should be '" << correctTag << "'.";
        if (wrongTag == impl.preaccumulationTag) {
          std::cerr << " The value seems to be a preaccumulation output.";
        } else if (correctTag == impl.preaccumulationTag) {
          std::cerr << " The value seems to be used during a preaccumulation but is not declared as an input.";
        }
        std::cerr << std::endl;
      }

      CODI_INLINE void checkLhsError(Real& lhsValue, ActiveTypeTapeData& lhsData, const Real& rhs) const {
        if (lhsData.properties.test(TagFlags::DoNotChange)) {
          if (lhsValue != rhs) {
            tagPropertyErrorCallback(lhsValue, rhs, TagFlags::DoNotChange, tagPropertyErrorUserData);
          }
        } else if (lhsData.properties.test(TagFlags::DoNotWrite)) {
          tagPropertyErrorCallback(lhsValue, rhs, TagFlags::DoNotWrite, tagPropertyErrorUserData);
        }
      }

      template<typename Lhs>
      CODI_INLINE void checkLhsError(LhsExpressionInterface<Real, Gradient, Impl, Lhs>& lhs, Real const& rhs) const {
        checkLhsError(lhs.cast().value(), lhs.cast().getTapeData(), rhs);
      }

      CODI_INLINE void handleError(ValidationIndicator<Real, Tag>& vi) const {
        if (vi.hasError) {
          if (vi.hasTagError) {
            tagErrorCallback(curTag, vi.errorTag, tagErrorUserData);
          }
          if (vi.hasUseError) {
            tagPropertyErrorCallback(vi.value, vi.value, TagFlags::DoNotUse, tagPropertyErrorUserData);
          }
        }
      }

      template<typename Lhs>
      CODI_INLINE void verifyRegisterValue(LhsExpressionInterface<Real, Gradient, Impl, Lhs>& value,
                                           ActiveTypeTapeData const& tag) {
        ValidationIndicator<Real, Tag> vi;
 
        verifyTag(vi, tag.tag);
        verifyProperties(vi, value.cast().getValue(), tag.properties);
        handleError(vi);
 
        checkLhsError(value, value.cast().getValue());
      }

      CODI_INLINE void setTag(Tag& tag) const {
        tag = curTag;
      }

      CODI_INLINE void resetTag(Tag& tag) const {
        tag = Tag();
      }

 
    private:
      CODI_INLINE Impl& cast() {
        return static_cast<Impl&>(*this);
      }
  };
}