phv_fields.h

 
#ifndef BF_P4C_PHV_PHV_FIELDS_H_
#define BF_P4C_PHV_PHV_FIELDS_H_
 
#include <functional>
#include <limits>
#include <optional>
 
#include <boost/range/irange.hpp>
 
#include "bf-p4c/bf-p4c-options.h"
#include "bf-p4c/device.h"
#include "bf-p4c/ir/bitrange.h"
#include "bf-p4c/ir/thread_visitor.h"
#include "bf-p4c/ir/tofino_write_context.h"
#include "bf-p4c/lib/assoc.h"
#include "bf-p4c/lib/cmp.h"
#include "bf-p4c/lib/union_find.hpp"
#include "bf-p4c/phv/constraints/constraints.h"
#include "bf-p4c/phv/phv.h"
#include "bf-p4c/phv/phv_parde_mau_use.h"
#include "bf-p4c/phv/utils/slice_alloc.h"
#include "ir/ir.h"
#include "lib/algorithm.h"
#include "lib/map.h"
#include "lib/ordered_map.h"
#include "lib/ordered_set.h"
#include "lib/range.h"
#include "lib/safe_vector.h"
#include "lib/symbitmatrix.h"
 
using namespace P4;
 
struct FieldAlignment {
    explicit FieldAlignment(nw_bitrange bitLayout);
    explicit FieldAlignment(le_bitrange bitLayout);
 
    bool operator==(const FieldAlignment &other) const;
    bool operator!=(const FieldAlignment &other) const;
 
    bool isByteAligned() const { return align == 0; }
 
    unsigned align;
};
 
std::ostream &operator<<(std::ostream &, const FieldAlignment &);
 
namespace PHV {
 
using SolitaryReason = Constraints::SolitaryConstraint::SolitaryReason;
using DigestType = Constraints::DigestConstraint::DigestType;
using AlignmentReason = Constraints::AlignmentConstraint::AlignmentReason;
 
class FieldSlice;
 
enum class FieldKind : unsigned short {
    header = 0,    // header fields
    metadata = 1,  // metadata fields
    pov = 2        // POV fields, eg. $valid
};
 
enum class FieldAccessType { NONE = 0, R = 1, W = 2, RW = 3 };
 
class AllocContext {
 public:
    enum class Type { PARSER, TABLE, DEPARSER };
    Type type;
 
    const IR::MAU::Table *table;
 
 private:
    explicit AllocContext(Type type) : type(type), table(nullptr) {
        BUG_CHECK(type != Type::TABLE, "Improper usage of PHV::AllocContext interface");
    }
 
    explicit AllocContext(const IR::MAU::Table *table) : type(Type::TABLE), table(table) {
        BUG_CHECK(table, "Improper usage of PHV::AllocContext interface");
    }
 
 public:
    bool is_parser() const { return type == Type::PARSER; }
    bool is_deparser() const { return type == Type::DEPARSER; }
    bool is_table() const { return type == Type::TABLE; }
    cstring typeStr() const {
        if (is_parser())
            return "PARSER"_cs;
        else if (is_deparser())
            return "DEPARSER"_cs;
        else if (is_table())
            return "TABLE"_cs;
        return "NONE"_cs;
    }
 
    static const AllocContext *PARSER;
    static const AllocContext *DEPARSER;
 
    static const AllocContext *of_unit(const IR::BFN::Unit *unit) {
        if (!unit) return nullptr;
        if (unit->is<IR::BFN::ParserState>() || unit->is<IR::BFN::Parser>() ||
            unit->is<IR::BFN::GhostParser>())
            return PARSER;
        if (unit->to<IR::BFN::Deparser>()) return DEPARSER;
        if (auto table = unit->to<IR::MAU::Table>()) return new AllocContext(table);
        BUG("Improper usage of PHV::AllocContext interface. Not a parser, deparser, or table: %1%",
            unit);
    }
};
std::ostream &operator<<(std::ostream &, const AllocContext &);
 
struct FieldOperation {
    bool is_bitwise_op;
    bool is_salu_inst;
    const IR::MAU::Instruction *inst;
    FieldAccessType rw_type;
    le_bitrange range;  // If range.size() == this->size, then the operation is
                        // over the whole field.
    FieldOperation(bool is_bitwise_op, bool is_salu_inst, const IR::MAU::Instruction *inst,
                   FieldAccessType rw_type, le_bitrange range)
        : is_bitwise_op(is_bitwise_op),
          is_salu_inst(is_salu_inst),
          inst(inst),
          rw_type(rw_type),
          range(range) {}
};
 
class Field;
 
class Field : public LiftLess<Field> {
 public:
    cstring name;
 
    int id = 0;
 
    gress_t gress = INGRESS;
 
    bool isGhostField() const {
        if (BackendOptions().arch == "tna") {
            return name.startsWith("ghost::");
        }
        if (name.startsWith("ghost::")) return true;
        // A field valid in both ingress && ghost e.g. ping pong reg does not
        // have a 'ghost::" prefix and above check is not sufficient to identify
        // it to be valid ghost field.
        if (name.startsWith("ingress::")) return false;
        if (name.startsWith("egress::")) return false;
        // FIXME: For no prefix we assume this to be valid in ghost field. Needs
        // to be fixed by relying on 'gress' field rather than prefix
        return true;
    }
 
    bool isCompilerGeneratedPaddingField() const {
        return name.startsWith("__phv_dummy_padding__");
    }
 
    int size = 0;
 
    std::optional<FieldAlignment> alignment;
    std::list<std::pair<FieldAlignment, Util::SourceInfo>> alignmentSources;
 
    nw_bitrange validContainerRange_i = ZeroToMax();
 
    int offset = 0;
 
    bool metadata = false;
 
    bool intrinsic_i = false;
 
    bool invalidate_from_arch_i = false;
 
    bool bridged = false;
 
    bool padding = false;
 
    bool overlayable = false;
 
    bool emitted_i = false;
 
    // Define field allocation status.
    enum alloc_code_t {
        EMPTY = 0,
        REFERENCED = 1 << 0,           // Field is referenced
        HAS_PHV_ALLOCATION = 1 << 1,   // Field is at least partially PHV-allocated
        FULLY_PHV_ALLOCATED = 1 << 2,  // Field is fully PHV-allocated
        HAS_CLOT_ALLOCATION = 1 << 3,  // Field is at least partially CLOT-allocated
    };
 
    typedef unsigned AllocState;
 
    struct mirror_field_list_t {
        Field *member_field;
        int field_list;
        bool operator==(const mirror_field_list_t &rhs) const {
            return rhs.member_field == this->member_field && rhs.field_list == this->field_list;
        }
        bool operator!=(const mirror_field_list_t &rhs) const { return !(*this == rhs); }
    } mirror_field_list = {nullptr, -1};
 
    bool pov = false;
 
    const PHV::Field *aliasSource = nullptr;
 
    std::optional<Util::SourceInfo> srcInfo;
 
    void setStartBits(PHV::Size size, bitvec startPositions);
 
    bitvec getStartBits(PHV::Size size) const;
 
    cstring header() const { return name.before(strrchr(name, '.')); }
 
 private:
    std::optional<cstring> externalName_i;
 
    // constraints on this field
    //
    bool flexible_i = false;
    bool parsed_i = false;    
    bool deparsed_i = false;  
    // Solitary Constraint: This field cannot be packed with any other field (although it may share
    // a container with another field through overlay).
    Constraints::SolitaryConstraint solitary_i;
 
    // Digest Constraint: This field is used in a digest. This constraint also contains the type of
    // digest this field is used in.
    Constraints::DigestConstraint digest_i;
 
    // Alignment Constraint: This field must be aligned at given offset within a container.
    Constraints::AlignmentConstraint alignment_i;
 
    bool deparsed_bottom_bits_i = false;  
    bool deparsed_top_bits_i = false;     
    bool exact_containers_i = false;      
 
    bool deparsed_to_tm_i = false;  
    size_t numNoPack = 0;           
 
    bool is_checksummed_i = false;           
    bool mocha_i = false;                    
    bool dark_i = false;                     
    bool deparser_zero_i = false;            
    bool write_force_immediate_i = false;    
    ordered_set<int> wide_arith_start_bit_;  
    bool ignore_alloc_i = false;
 
    // true if the field is part of Type_FixedSizeHeader, used to represent resubmit/phase0 data.
    bool fixed_size_i = false;
 
    bool same_container_group_i = false;  
 
    PHV::Size prefer_container_size_i = PHV::Size::null;
 
    bool no_holes_i = false;
 
    bool upcasted_i = false;  
 
    int maxContainerBytes_i = -1;
 
    std::vector<le_bitrange> no_split_ranges_i;
 
    bool is_marshaled_i = false;
 
    std::optional<bitvec> limited_container_ids_i = std::nullopt;
 
    // Maximum field size in the same SuperCluster with no_split constraint.
    // Used by bridged metadata packing to insert padding after the 'no_split'
    // bridged field, if the bridged field is smaller than the related
    // 'no_split' field.
    int no_split_container_size_i = -1;
 
    safe_vector<FieldOperation> operations_i;
 
    // Do not allocate this field in phv or clots. Use for local parser variables.
    bool avoid_alloc_i = false;
 
    safe_vector<PHV::AllocSlice> alloc_slice_i;
 
    friend std::ostream &operator<<(std::ostream &out, const Field &field);
 
 public:
    bool is_flexible() const { return flexible_i; }
    void set_flexible(bool b) { flexible_i = b; }
    bool is_tphv_candidate(const PhvUse &uses) const;
    bool is_mocha_candidate() const { return mocha_i; }
    bool is_dark_candidate() const { return dark_i; }
    bool is_deparser_zero_candidate() const { return deparser_zero_i; }
    void set_mocha_candidate(bool c) { mocha_i = c; }
    void set_dark_candidate(bool c) { dark_i = c; }
    void set_deparser_zero_candidate(bool c) { deparser_zero_i = c; }
 
    bool is_ignore_alloc() const { return ignore_alloc_i; }
    void set_ignore_alloc(bool b) { ignore_alloc_i = b; }
 
    bool is_avoid_alloc() const { return avoid_alloc_i; }
    void set_avoid_alloc(bool a) { avoid_alloc_i = a; }
 
    bool is_padding() const { return padding; }
    void set_padding(bool p) { padding = p; }
    bool is_overlayable() const { return overlayable; }
    void set_overlayable(bool p) { overlayable = p; }
    bool is_fixed_size_header() const { return fixed_size_i; }
    void set_fixed_size_header(bool f) { fixed_size_i = f; }
 
    bool emitted() const { return emitted_i; }
    void set_emitted(bool b) { emitted_i = b; }
 
    bool is_upcasted() const { return upcasted_i; }
    void set_upcasted(bool c) { upcasted_i = c; }
 
    //
    // constraints
    //
    bool parsed() const { return parsed_i; }
    void set_parsed(bool b) { parsed_i = b; }
    bool deparsed() const { return deparsed_i; }
    void set_deparsed(bool b) { deparsed_i = b; }
 
    bool is_solitary() const { return solitary_i.hasConstraint(); }
    void set_solitary(uint32_t reason) { solitary_i.addConstraint(reason); }
 
    const Constraints::SolitaryConstraint &getSolitaryConstraint() const { return solitary_i; }
 
    bool is_digest() const { return digest_i.hasConstraint(); }
    void set_digest(uint32_t source) { digest_i.addConstraint(source); }
 
    const Constraints::DigestConstraint &getDigestConstraint() const { return digest_i; }
 
    // only update the alignment constraint used by bridged packing
    void set_alignment(Constraints::AlignmentConstraint &c) { alignment_i = c; }
    void set_alignment(unsigned r, unsigned v) { alignment_i.addConstraint(r, v); }
    void erase_alignment() { alignment_i.eraseConstraint(); }
    const Constraints::AlignmentConstraint &getAlignmentConstraint() const { return alignment_i; }
 
    bool deparsed_bottom_bits() const { return deparsed_bottom_bits_i; }
    void set_deparsed_bottom_bits(bool b) { deparsed_bottom_bits_i = b; }
    bool deparsed_top_bits() const { return deparsed_top_bits_i; }
    void set_deparsed_top_bits(bool b) { deparsed_top_bits_i = b; }
    bool exact_containers() const { return exact_containers_i; }
    void set_exact_containers(bool b) { exact_containers_i = b; }
    void set_written_in_force_immediate(bool b) { write_force_immediate_i = b; }
    bool written_in_force_immediate_table() const { return write_force_immediate_i; }
 
    void set_no_split_container_size(int size) { no_split_container_size_i = size; }
    int no_split_container_size() const { return no_split_container_size_i; }
    bool no_split() const;
    void set_no_split(bool b);
    bool no_split_at(int pos) const;
    bool has_no_split_at_pos() const;
    void set_no_split_at(le_bitrange range);  // The indicated slice cannot be split.
 
    bool same_container_group() const { return same_container_group_i; }
    void set_same_container_group(bool b) { same_container_group_i = b; }
 
    bool no_holes() const { return no_holes_i; }
    void set_no_holes(bool b) { no_holes_i = b; }
 
    void set_prefer_container_size(PHV::Size cnt_size) { prefer_container_size_i = cnt_size; }
    PHV::Size prefer_container_size() const { return prefer_container_size_i; }
 
    bool used_in_wide_arith() const { return wide_arith_start_bit_.size() > 0; }
 
    bool bit_used_in_wide_arith(int slice_bit) const {
        for (auto bit : wide_arith_start_bit_) {
            if (slice_bit >= bit && slice_bit < (bit + 64)) return true;
        }
        return false;
    }
    bool bit_is_wide_arith_lo(int slice_bit) const {
        for (auto bit : wide_arith_start_bit_) {
            if (slice_bit < (bit + 32)) return true;
        }
        return false;
    }
 
    // Only called for least signficant bit of wide arith operation.
    // Returns true if could successfully add constraint.
    bool add_wide_arith_start_bit(int start_bit) {
        for (auto bit : wide_arith_start_bit_) {
            if (bit != start_bit) {
                // conflicting constraint if start bit has to go to both
                // odd and even container locations
                if (bit < start_bit && start_bit < (bit + 64)) return false;
                if (start_bit < bit && bit < (start_bit + 64)) return false;
            }
        }
        wide_arith_start_bit_.insert(start_bit);
        return true;
    }
    std::vector<le_bitrange> no_split_ranges() const { return no_split_ranges_i; }
 
    bool deparsed_to_tm() const { return deparsed_to_tm_i; }
    void set_deparsed_to_tm(bool b) { deparsed_to_tm_i = b; }
 
    bool is_marshaled() const { return is_marshaled_i; }
    void set_is_marshaled(bool b) { is_marshaled_i = b; }
 
    bool is_checksummed() const { return is_checksummed_i; }
    void set_is_checksummed(bool b) { is_checksummed_i = b; }
    bool is_intrinsic() const { return intrinsic_i; }
    void set_intrinsic(bool b) { intrinsic_i = b; }
    bool is_invalidate_from_arch() const { return invalidate_from_arch_i; }
    void set_invalidate_from_arch(bool b) { invalidate_from_arch_i = b; }
 
    void set_limited_container_ids(const std::optional<bitvec> &ids) {
        limited_container_ids_i = ids;
    }
    const std::optional<bitvec> &limited_container_ids() const { return limited_container_ids_i; }
 
    // @returns the set of MAU operations on this field.
    const safe_vector<FieldOperation> &operations() const { return operations_i; }
 
    // @returns the set of MAU operations on this field.
    safe_vector<FieldOperation> &operations() { return operations_i; }
 
    void set_num_pack_conflicts(size_t no) { numNoPack = no; }
 
    size_t num_pack_conflicts() const { return numNoPack; }
 
    bool hasMaxContainerBytesConstraint() const { return maxContainerBytes_i != -1; }
 
    int getMaxContainerBytes() const { return maxContainerBytes_i; }
 
    void setMaxContainerBytes(int size) { maxContainerBytes_i = size; }
 
    bool isPacketField() const { return (!metadata && !pov); }
 
    const PHV::AllocSlice &for_bit(int bit) const;
 
    void foreach_byte(le_bitrange r, const PHV::AllocContext *ctxt, const PHV::FieldUse *use,
                      std::function<void(const PHV::AllocSlice &)> fn,
                      SliceMatch useTblRefs = SliceMatch::DFLT) const;
    void foreach_byte(le_bitrange r, const IR::MAU::Table *ctxt, const PHV::FieldUse *use,
                      std::function<void(const PHV::AllocSlice &)> fn,
                      SliceMatch useTblRefs = SliceMatch::DFLT) const {
        foreach_byte(r, PHV::AllocContext::of_unit(ctxt), use, fn, useTblRefs);
    }
 
    void foreach_byte(const PHV::AllocContext *ctxt, const PHV::FieldUse *use,
                      std::function<void(const PHV::AllocSlice &)> fn,
                      SliceMatch useTblRefs = SliceMatch::DFLT) const {
        foreach_byte(StartLen(0, this->size), ctxt, use, fn, useTblRefs);
    }
    void foreach_byte(const IR::MAU::Table *ctxt, const PHV::FieldUse *use,
                      std::function<void(const PHV::AllocSlice &)> fn,
                      SliceMatch useTblRefs = SliceMatch::DFLT) const {
        foreach_byte(PHV::AllocContext::of_unit(ctxt), use, fn, useTblRefs);
    }
 
    void foreach_byte(const le_bitrange *r, const PHV::AllocContext *ctxt, const PHV::FieldUse *use,
                      std::function<void(const PHV::AllocSlice &)> fn,
                      SliceMatch useTblRefs = SliceMatch::DFLT) const {
        foreach_byte(r ? *r : StartLen(0, this->size), ctxt, use, fn, useTblRefs);
    }
    void foreach_byte(const le_bitrange *r, const IR::MAU::Table *ctxt, const PHV::FieldUse *use,
                      std::function<void(const PHV::AllocSlice &)> fn,
                      SliceMatch useTblRefs = SliceMatch::DFLT) const {
        foreach_byte(r, PHV::AllocContext::of_unit(ctxt), use, fn, useTblRefs);
    }
 
    const std::vector<PHV::AllocSlice> get_combined_alloc_bytes(
        const PHV::AllocContext *ctxt, const PHV::FieldUse *use,
        SliceMatch useTblRefs = SliceMatch::DFLT) const;
 
    const std::vector<PHV::AllocSlice> get_combined_alloc_slices(le_bitrange bits,
                                                                 const PHV::AllocContext *ctxt,
                                                                 const PHV::FieldUse *use) const;
 
    void foreach_alloc(le_bitrange r, const PHV::AllocContext *ctxt, const PHV::FieldUse *use,
                       std::function<void(const PHV::AllocSlice &)> fn,
                       SliceMatch useTblRefs = SliceMatch::DFLT) const;
 
    void foreach_alloc(le_bitrange r, const IR::MAU::Table *ctxt, const PHV::FieldUse *use,
                       std::function<void(const PHV::AllocSlice &)> fn,
                       SliceMatch useTblRefs = SliceMatch::DFLT) const {
        foreach_alloc(r, PHV::AllocContext::of_unit(ctxt), use, fn, useTblRefs);
    }
 
    void foreach_alloc(le_bitrange r, std::function<void(const PHV::AllocSlice &)> fn,
                       SliceMatch useTblRefs = SliceMatch::DFLT) const {
        foreach_alloc(r, (PHV::AllocContext *)nullptr, nullptr, fn, useTblRefs);
    }
 
    void foreach_alloc(const PHV::AllocContext *ctxt, const PHV::FieldUse *use,
                       std::function<void(const PHV::AllocSlice &)> fn,
                       SliceMatch useTblRefs = SliceMatch::DFLT) const {
        foreach_alloc(StartLen(0, this->size), ctxt, use, fn, useTblRefs);
    }
 
    void foreach_alloc(const IR::MAU::Table *ctxt, const PHV::FieldUse *use,
                       std::function<void(const PHV::AllocSlice &)> fn,
                       SliceMatch useTblRefs = SliceMatch::DFLT) const {
        foreach_alloc(PHV::AllocContext::of_unit(ctxt), use, fn, useTblRefs);
    }
 
    void foreach_alloc(std::function<void(const PHV::AllocSlice &)> fn,
                       SliceMatch useTblRefs = SliceMatch::DFLT) const {
        foreach_alloc((PHV::AllocContext *)nullptr, nullptr, fn, useTblRefs);
    }
 
    void foreach_alloc(const le_bitrange *r, const PHV::AllocContext *ctxt,
                       const PHV::FieldUse *use, std::function<void(const PHV::AllocSlice &)> fn,
                       SliceMatch useTblRefs = SliceMatch::DFLT) const {
        foreach_alloc(r ? *r : StartLen(0, this->size), ctxt, use, fn, useTblRefs);
    }
 
    void foreach_alloc(const le_bitrange *r, const IR::MAU::Table *ctxt, const PHV::FieldUse *use,
                       std::function<void(const PHV::AllocSlice &)> fn,
                       SliceMatch useTblRefs = SliceMatch::DFLT) const {
        foreach_alloc(r, PHV::AllocContext::of_unit(ctxt), use, fn, useTblRefs);
    }
 
    int container_bytes(std::optional<le_bitrange> bits = std::nullopt) const;
 
    void clear_alloc() { alloc_slice_i.clear(); }
 
    void add_alloc(const PHV::AllocSlice &alloc) { alloc_slice_i.push_back(alloc); }
 
    PHV::AllocSlice *add_and_return_alloc(const Field *f, PHV::Container c, int fb, int cb, int w,
                                          const ActionSet &a) {
        alloc_slice_i.emplace_back(f, c, fb, cb, w, a);
        unsigned size = alloc_slice_i.size();
        return &(alloc_slice_i[size - 1]);
    }
 
    void set_alloc(const safe_vector<PHV::AllocSlice> &alloc) { alloc_slice_i = alloc; }
 
    const safe_vector<PHV::AllocSlice> &get_alloc() const { return alloc_slice_i; }
 
    safe_vector<PHV::AllocSlice> &get_alloc() { return alloc_slice_i; }
 
    size_t alloc_size() const { return alloc_slice_i.size(); }
 
    bool is_unallocated() const { return alloc_slice_i.empty(); }
 
    void sort_alloc() {
        std::sort(alloc_slice_i.begin(), alloc_slice_i.end(),
                  [](PHV::AllocSlice l, PHV::AllocSlice r) {
                      if (l.field_slice().lo != r.field_slice().lo)
                          return l.field_slice().lo > r.field_slice().lo;
                      return l.getEarliestLiveness().first > r.getEarliestLiveness().first;
                  });
    }
 
    void updateAlignment(PHV::AlignmentReason, const FieldAlignment &newAlignment,
                         const Util::SourceInfo &newAlignmentSource);
 
    void eraseAlignment();
 
    void updateValidContainerRange(nw_bitrange newValidRange);
 
    cstring externalName() const { return externalName_i ? *externalName_i : name; }
 
    bool hasExternalName() const { return externalName_i != std::nullopt; }
 
    void setExternalName(cstring name) { externalName_i = name; }
 
    void clearExternalName() { externalName_i = std::nullopt; }
 
    nw_bitrange validContainerRange() const { return validContainerRange_i; }
 
    le_bitrange byteAlignedRangeInBits() const {
        int start = 8 * (offset / 8);
        int len = (8 * ROUNDUP(offset + size, 8)) - start;
        return StartLen(start, len);
    }
 
    bool hasPhvAllocation(AllocState s) const {
        return (s & HAS_PHV_ALLOCATION) || (s & FULLY_PHV_ALLOCATED);
    }
    bool hasClotAllocation(AllocState s) const { return s & HAS_CLOT_ALLOCATION; }
 
    bool hasAllocation(AllocState s) const { return hasPhvAllocation(s) || hasClotAllocation(s); }
 
    bool fullyPhvAllocated(AllocState s) const { return s & FULLY_PHV_ALLOCATED; }
    bool partiallyPhvAllocated(AllocState s) const {
        return hasPhvAllocation(s) && !fullyPhvAllocated(s);
    }
    bool isReferenced(AllocState s) const { return (s & REFERENCED) || hasAllocation(s); }
 
 private:
 
    // TODO: This is currently only used for SALU operands.  However,
    // it's general enough to support bit-in-byte alignment requirements
    // (alignment_i), valid container range requirements, and deparsed_to_tm.
    std::map<PHV::Size, bitvec> startBitsByContainerSize_i;
 
 public:
    Field() {
        for (auto size : Device::phvSpec().containerSizes())
            startBitsByContainerSize_i[size] = bitvec(0, int(size));
    }
 
    //
    // The precise ordering here is unimportant, as long as it is stable across different compiler
    // runs.
    bool operator<(const Field &other) const { return name < other.name; }
 
    void setStartBitsToLowerBitsOfBottomByte();
};
 
class AbstractField {
 public:
    AbstractField() {}
    virtual ~AbstractField() {}
    virtual int size() const = 0;
    virtual const PHV::Field *field() const = 0;
    virtual const le_bitrange &range() const = 0;
    template <typename T>
    const T &as() const {
        return dynamic_cast<const T &>(this);
    }
    template <typename T>
    const T *to() const {
        return dynamic_cast<const T *>(this);
    }
    template <typename T>
    bool is() const {
        return to<T>() != nullptr;
    }
    static AbstractField *create(const PhvInfo &, const IR::Expression *);
};
 
class Constant : public AbstractField {
    le_bitrange range_i;
 
 public:
    explicit Constant(const IR::Constant *value) : value(value) {
        range_i = {0, value->type->width_bits() - 1};
    }
 
    int size() const override { return value->type->width_bits(); }
    const PHV::Field *field() const override { return nullptr; }
    const le_bitrange &range() const override { return range_i; }
    const IR::Constant *value;
};
 
class FieldSlice : public AbstractField, public LiftCompare<FieldSlice> {
    // There is no reason for a FieldSlice to change the field it is representing, so make this
    // const (also used in ActionPhvConstraints)
    const PHV::Field *field_i;
    le_bitrange range_i;
    std::optional<FieldAlignment> alignment_i = std::nullopt;
    nw_bitrange validContainerRange_i = ZeroToMax();
 
 public:
    FieldSlice() : field_i(nullptr), range_i(StartLen(0, 0)) {}
 
    FieldSlice(const Field *field, le_bitrange range);
 
    explicit FieldSlice(const Field *field)
        : FieldSlice(field, le_bitrange(StartLen(0, field->size))) {}
 
    FieldSlice(FieldSlice slice, le_bitrange range) : FieldSlice(slice.field(), range) {
        BUG_CHECK(slice.range().contains(range),
                  "Trying to create field sub-slice larger than the original slice");
    }
 
    explicit operator bool() const { return field_i != nullptr; }
 
    le_bitrange byteAlignedRangeInBits() const {
        int start = 8 * ((field_i->offset + range_i.lo) / 8);
        int len = (8 * ROUNDUP(field_i->offset + range_i.hi + 1, 8)) - start;
        return StartLen(start, len);
    }
 
    cstring shortString() const {
        if (is_whole_field()) return field_i->name;
 
        std::stringstream ss;
        ss << field_i->name << "[" << range_i.hi << ":" << range_i.lo << "]";
        return ss.str();
    }
 
    bool operator==(const FieldSlice &other) const override {
        return field_i == other.field() && range_i == other.range();
    }
 
    bool operator<(const FieldSlice &other) const override {
        if (field_i != other.field()) return Field::less(field_i, other.field());
        if (range_i.lo != other.range().lo) return range_i.lo < other.range().lo;
        return range_i.hi < other.range().hi;
    }
 
    gress_t gress() const { return field_i->gress; }
 
    int size() const override { return range_i.size(); }
 
    std::optional<FieldAlignment> alignment() const { return alignment_i; }
 
    nw_bitrange validContainerRange() const { return validContainerRange_i; }
 
    FieldKind kind() const {
        // TODO: PHV::Field::metadata and PHV::Field::pov should be
        // replaced by FieldKind.
        if (field_i->pov)
            return FieldKind::pov;
        else if (field_i->metadata)
            return FieldKind::metadata;
        else
            return FieldKind::header;
    }
 
    const PHV::Field *field() const override { return field_i; }
 
    const le_bitrange &range() const override { return range_i; }
 
    bool is_whole_field() const { return range_i == StartLen(0, field_i->size); }
 
    bitvec getStartBits(PHV::Size size) const;
 
    bool is_tphv_candidate(const PhvUse &uses) const;
 
    // methods that just forward to the underlying PHV::Field method
    int container_bytes() const { return field_i->container_bytes(range_i); }
    template <class FN>
    void foreach_byte(const PHV::AllocContext *ctxt, const PHV::FieldUse *use, FN fn) const {
        field_i->foreach_byte(range_i, ctxt, use, fn);
    }
    template <class FN>
    void foreach_byte(const IR::MAU::Table *ctxt, const PHV::FieldUse *use, FN fn) const {
        field_i->foreach_byte(range_i, PHV::AllocContext::of_unit(ctxt), use, fn);
    }
 
    bool is_unallocated() const { return field_i->is_unallocated(); }
 
    friend size_t hash_value(const FieldSlice &fs) {
        size_t h = 0;
        boost::hash_combine(h, fs.field()->id);
        boost::hash_combine(h, fs.range().lo);
        boost::hash_combine(h, fs.range().hi);
        return h;
    }
};
 
struct FieldRange {
    cstring field_name;
    le_bitrange range;
    ordered_set<FieldRange> conflicts;
 
    bool operator==(const FieldRange &other) const {
        return (field_name == other.field_name) && range == other.range;
    }
 
    bool operator<(const FieldRange &other) const {
        if (field_name != other.field_name) return (field_name < other.field_name);
        if (range.lo != other.range.lo) return range.lo < other.range.lo;
        return range.hi < other.range.hi;
    }
 
    bool has_conflict(const FieldRange fld_range) const { return (conflicts.count(fld_range) > 0); }
};
 
struct PackingLayout {
    using FieldRange = std::pair<const PHV::Field *, le_bitrange>;
    class FieldRangeOrPadding {
        std::optional<FieldRange> slice;
        int padding = 0;
 
     public:
        explicit FieldRangeOrPadding(const FieldRange &fs) : slice(fs) {}
        explicit FieldRangeOrPadding(int n_padding_bits) : padding(n_padding_bits) {}
        bool is_fs() const { return slice.has_value(); }
        const FieldRange &fs() const { return *slice; }
        int size() const {
            if (is_fs())
                return slice->second.size();
            else
                return padding;
        }
    };
 
    safe_vector<FieldRangeOrPadding> layout;
    gress_t gress;
};
 
std::ostream &operator<<(std::ostream &out, const Field &);
std::ostream &operator<<(std::ostream &out, const Field *);
std::ostream &operator<<(std::ostream &out, const PackingLayout &);
std::ostream &operator<<(std::ostream &out, const PackingLayout *);
 
}  // namespace PHV
 
using InsertionConstraints = std::pair<std::set<UniqueId>, std::set<UniqueId>>;
 
using ConstraintMap = ordered_map<const IR::MAU::Table *, InsertionConstraints>;
 
class PhvInfo {
 public:
    // min-stage-based mapping from table to stages.
    static ordered_map<cstring, std::set<int>> table_to_min_stages;
    // physical-stage-based mapping from table to physical stages of the last table placement.
    static ordered_map<cstring, std::set<int>> table_to_physical_stages;
    static int deparser_stage;
    static bool darkSpillARA;
    static const bool DARK_SPILL_ARA_DEFAULT = true;
 
    struct DumpPhvFields : public Visitor {
        const PhvInfo &phv;
        const PhvUse &uses;
 
        explicit DumpPhvFields(const PhvInfo &phv, const PhvUse &uses) : phv(phv), uses(uses) {}
 
        const IR::Node *apply_visitor(const IR::Node *n, const char *) override;
        void generate_field_histogram(gress_t) const;
    };
 
    struct StructInfo {
        bool metadata;
 
        gress_t gress;
 
        int first_field_id;
 
        int size;
 
        StructInfo(bool metadata, gress_t gress)
            : metadata(metadata), gress(gress), first_field_id(0), size(0) {}
        StructInfo(bool metadata, gress_t gress, int first_field_id, int size)
            : metadata(metadata), gress(gress), first_field_id(first_field_id), size(size) {
            BUG_CHECK(0 <= size, "PhvInfo::StructInfo with negative size");
            BUG_CHECK(size == 0 || 0 <= first_field_id,
                      "PhvInfo::StructInfo with negative first field offset");
        }
 
        boost::integer_range<int> field_ids() const {
            return boost::irange(first_field_id, first_field_id + size);
        }
    };
 
    struct SameContainerAllocConstraint {
        using FieldBit = std::pair<const PHV::Field *, int>;
        UnionFind<FieldBit> same_byte_bits;
 
        // return true if the two field slice must share a container.
        bool same_container(const PHV::FieldSlice &a, const PHV::FieldSlice &b) const;
        void clear() { same_byte_bits.clear(); }
    };
 
    const SymBitMatrix &field_mutex() const { return field_mutex_i; }
    const SymBitMatrix &metadata_mutex() const { return metadata_mutex_i; }
    const SymBitMatrix &dark_mutex() const { return dark_mutex_i; }
    const SymBitMatrix &deparser_no_pack_mutex() const { return deparser_no_pack_i; }
    const SymBitMatrix &digest_no_pack_mutex() const { return digest_no_pack_i; }
    const SameContainerAllocConstraint &same_container_alloc_constraint() const {
        return same_container_alloc_i;
    }
    SymBitMatrix &field_mutex() { return field_mutex_i; }
    SymBitMatrix &metadata_mutex() { return metadata_mutex_i; }
    SymBitMatrix &dark_mutex() { return dark_mutex_i; }
    SymBitMatrix &deparser_no_pack_mutex() { return deparser_no_pack_i; }
    SymBitMatrix &digest_no_pack_mutex() { return digest_no_pack_i; }
 
    SymBitMatrix &getBridgedExtractedTogether() { return bridged_extracted_together_i; }
    const SymBitMatrix &getBridgedExtractedTogether() const { return bridged_extracted_together_i; }
    SameContainerAllocConstraint &same_container_alloc_constraint() {
        return same_container_alloc_i;
    }
 
    bool are_bridged_extracted_together(const PHV::Field *f1, const PHV::Field *f2) const {
        BUG_CHECK(f1 && f2, "No PHV field");
        return bridged_extracted_together_i(f1->id, f2->id);
    }
 
    SymBitMatrix &getMutuallyAligned() { return mutually_aligned_i; }
    const SymBitMatrix &getMutuallyAligned() const { return mutually_aligned_i; }
    bool are_mutually_aligned(const PHV::Field *f1, const PHV::Field *f2) const {
        BUG_CHECK(f1 && f2, "No PHV field");
        return mutually_aligned_i(f1->id, f2->id);
    }
 
    void addMutuallyAligned(const PHV::Field *f1, const PHV::Field *f2) {
        BUG_CHECK(f1 && f2, "No PHV field");
        mutually_aligned_i(f1->id, f2->id) = true;
    }
 
    void addDeparserNoPack(const PHV::Field *f1, const PHV::Field *f2) {
        BUG_CHECK(f1 && f2, "No PHV field");
        deparser_no_pack_i(f1->id, f2->id) = true;
    }
 
    void addFieldNoPack(const PHV::Field *f1, const PHV::Field *f2) {
        BUG_CHECK(f1 && f2, "No PHV field");
        field_no_pack_i(f1->id, f2->id) = true;
    }
 
    void removeFieldNoPack(const PHV::Field *f1, const PHV::Field *f2) {
        BUG_CHECK(f1 && f2, "No PHV field");
        field_no_pack_i(f1->id, f2->id) = false;
    }
 
    void addDigestNoPack(const PHV::Field *f1, const PHV::Field *f2) {
        BUG_CHECK(f1 && f2, "No PHV field");
        digest_no_pack_i(f1->id, f2->id) = true;
    }
 
    void removeDigestNoPack(const PHV::Field *f1, const PHV::Field *f2) {
        BUG_CHECK(f1 && f2, "No PHV field");
        digest_no_pack_i(f1->id, f2->id) = false;
    }
 
    void addFieldMutex(const PHV::Field *f1, const PHV::Field *f2) {
        BUG_CHECK(f1 && f2, "No PHV field");
        field_mutex_i(f1->id, f2->id) = true;
    }
 
    void removeFieldMutex(const PHV::Field *f1, const PHV::Field *f2) {
        BUG_CHECK(f1 && f2, "No PHV field");
        field_mutex_i(f1->id, f2->id) = false;
    }
 
    void addMetadataMutex(const PHV::Field *f1, const PHV::Field *f2) {
        BUG_CHECK(f1 && f2, "No PHV field");
        metadata_mutex_i(f1->id, f2->id) = true;
    }
 
    void addDarkMutex(const PHV::Field *f1, const PHV::Field *f2) {
        BUG_CHECK(f1 && f2, "No PHV field");
        dark_mutex_i(f1->id, f2->id) = true;
    }
 
    bool isFieldMutex(const PHV::Field *f1, const PHV::Field *f2) const {
        BUG_CHECK(f1 && f2, "No PHV field");
        return field_mutex_i(f1->id, f2->id);
    }
 
    bool isMetadataMutex(const PHV::Field *f1, const PHV::Field *f2) const {
        BUG_CHECK(f1 && f2, "No PHV field");
        return metadata_mutex_i(f1->id, f2->id);
    }
 
    bool isDarkMutex(const PHV::Field *f1, const PHV::Field *f2) const {
        BUG_CHECK(f1 && f2, "No PHV field");
        return dark_mutex_i(f1->id, f2->id);
    }
 
    bool isDeparserNoPack(const PHV::Field *f1, const PHV::Field *f2) const {
        BUG_CHECK(f1 && f2, "No PHV field");
        return deparser_no_pack_i(f1->id, f2->id);
    }
 
    bool isFieldNoPack(const PHV::Field *f1, const PHV::Field *f2) const {
        BUG_CHECK(f1 && f2, "No PHV field");
        return field_no_pack_i(f1->id, f2->id);
    }
 
    bool isDigestNoPack(const PHV::Field *f1, const PHV::Field *f2) const {
        BUG_CHECK(f1 && f2, "No PHV field");
        return digest_no_pack_i(f1->id, f2->id);
    }
 
    unsigned sizeFieldNoPack() { return field_no_pack_i.size(); }
 
    void clearConstantExtractionState() {
        constantExtractedInSameState.clear();
        sameStateConstantExtraction.clear();
    }
 
    void insertConstantExtractField(PHV::Field *f) { sameStateConstantExtraction.insert(f); }
 
    void mergeConstantExtracts(PHV::Field *f, PHV::Field *g) {
        sameStateConstantExtraction.makeUnion(f, g);
        constantExtractedInSameState[f->id] = true;
        constantExtractedInSameState[g->id] = true;
    }
 
    const UnionFind<PHV::Field *> &getSameSetConstantExtraction() const {
        return sameStateConstantExtraction;
    }
 
    UnionFind<PHV::Field *> &getSameSetConstantExtraction() { return sameStateConstantExtraction; }
 
    bool hasParserConstantExtract(const PHV::Field *f) const {
        return constantExtractedInSameState[f->id];
    }
 
    // Return the insertion constraints for the AlwaysRunAction tables
    const ordered_map<gress_t, ConstraintMap> &getARAConstraints() const { return alwaysRunTables; }
 
    // Add insertion constraints for table @tbl in gress @grs
    bool add_table_constraints(gress_t grs, IR::MAU::Table *tbl, InsertionConstraints cnstrs) {
        bool has_constrs =
            (alwaysRunTables.count(grs) ? (alwaysRunTables[grs].count(tbl) ? true : false) : false);
 
        if (!has_constrs) {
            (alwaysRunTables[grs])[tbl] = cnstrs;
        } else {
            (alwaysRunTables[grs])[tbl].first.insert(cnstrs.first.begin(), cnstrs.first.end());
            (alwaysRunTables[grs])[tbl].second.insert(cnstrs.second.begin(), cnstrs.second.end());
        }
 
        return !has_constrs;
    }
 
    // Clear insertion constraints
    void clearARAconstraints() { alwaysRunTables.clear(); }
 
    static void clearMinStageInfo() { PhvInfo::table_to_min_stages.clear(); }
    static void clearPhysicalStageInfo() { PhvInfo::table_to_physical_stages.clear(); }
 
    static void resetDeparserStage() { PhvInfo::deparser_stage = -1; }
 
    static void setDeparserStage(int stage) { PhvInfo::deparser_stage = stage; }
 
    static int getDeparserStage() { return PhvInfo::deparser_stage; }
 
    static std::set<int> minStages(const IR::MAU::Table *tbl);
    static std::set<int> physicalStages(const IR::MAU::Table *tbl);
 
    static void addMinStageEntry(const IR::MAU::Table *tbl, int stage,
                                 bool remove_prev_stages = false);
    static void setPhysicalStages(const IR::MAU::Table *tbl, const std::set<int> &stage);
 
    static bool hasMinStageEntry(const IR::MAU::Table *tbl);
 
    static cstring reportMinStages();
 
    static void resetDarkSpillARA() { darkSpillARA = DARK_SPILL_ARA_DEFAULT; }
 
    // When a gateway and a table is merged together, we need to make sure that the slices used in
    // the gateway are alive at the table with which it is merged. @returns true if the liveness
    // check allows the merging of the gateway with the table.
    bool darkLivenessOkay(const IR::MAU::Table *gateway, const IR::MAU::Table *t) const;
 
    // return true if some bit of two fieldslice will share the same container after allocation.
    bool must_alloc_same_container(const PHV::FieldSlice &a, const PHV::FieldSlice &b) const {
        return same_container_alloc_i.same_container(a, b);
    }
 
 private:  // class PhvInfo
    //
    std::map<cstring, PHV::Field> all_fields;
    safe_vector<PHV::Field *> by_id;
 
    std::map<cstring, StructInfo> all_structs;
 
    // TODO: what about header unions?
    ordered_map<cstring, StructInfo> simple_headers;
 
    assoc::hash_map<PHV::Container, ordered_set<const PHV::Field *>> container_to_fields;
 
    ordered_set<cstring> dummyPaddingNames;
 
    ordered_map<const PHV::Field *, const PHV::Field *> aliasMap;
 
    ordered_map<cstring, PHV::Field *> externalNameMap;
 
    ordered_map<gress_t, ConstraintMap> alwaysRunTables;
 
    bool alloc_done_ = false;
    bool pov_alloc_done = false;
    bool trivial_alloc_ = false;  // MAU group constraints not met
 
    SymBitMatrix field_mutex_i;
 
    SymBitMatrix metadata_mutex_i;
 
    SymBitMatrix dark_mutex_i;
 
    SymBitMatrix deparser_no_pack_i;
 
    SymBitMatrix field_no_pack_i;
 
    SymBitMatrix digest_no_pack_i;
 
    SymBitMatrix bridged_extracted_together_i;
 
    SymBitMatrix mutually_aligned_i;
 
    ordered_map<const PHV::Field *, const IR::TempVar *> fields_to_tempvars_i;
 
    SameContainerAllocConstraint same_container_alloc_i;
 
    std::set<PHV::Container> zeroContainers[2];  // per gress
 
    ordered_map<cstring, ordered_set<cstring>> metadataDeps;
 
    // reverseMetadataDeps[t1] = { t_n }, means that all tables in t_n must be placed before we
    // place table t1.
    ordered_map<cstring, ordered_set<cstring>> reverseMetadataDeps;
 
    // For each of the table pairs in above 'metadataDeps' map, below map holds
    // the corresponding slice causing the dependency
    typedef std::pair<cstring, cstring> tpair;
    ordered_map<tpair, const PHV::FieldSlice *> metadataDepFields;
 
    // UnionFind struct in PhvInfo for all fields that are written in the same parser state using
    // constants.
    UnionFind<PHV::Field *> sameStateConstantExtraction;
 
    // Structure to quickly check membership in sameStateConstantExtraction.
    bitvec constantExtractedInSameState;
 
    void clear();
 
    void add_hdr(cstring headerName, const IR::Type_StructLike *type, gress_t gress,
                 bool isMetadata);
    void add_struct(cstring structName, const IR::Type_StructLike *type, gress_t gress, bool meta,
                    bool bridged, int offset);
    void addPadding(const IR::Padding *padding, gress_t gress);
 
    template <typename Iter>
    class iterator {
        Iter it;
 
     public:
        iterator(Iter i) : it(i) {}  // NOLINT(runtime/explicit)
        bool operator==(iterator a) { return it == a.it; }
        bool operator!=(iterator a) { return it != a.it; }
        iterator &operator++() {
            ++it;
            return *this;
        }
        iterator &operator--() {
            --it;
            return *this;
        }
        decltype(**it) operator*() { return **it; }
        decltype(*it) operator->() { return *it; }
    };
 
    friend class ClearPhvInfo;
    friend class CollectPhvFields;
    friend struct AllocatePOVBits;
    friend struct MarkBridgedMetadataFields;
 
    void allocatePOV(const BFN::HeaderStackInfo &);
 
 public:  // class PhvInfo
    PhvInfo() {}
    void addTempVar(const IR::TempVar *tempVar, gress_t gress);
    bool isTempVar(const PHV::Field *f) const { return fields_to_tempvars_i.count(f) > 0; }
    const PHV::Field *field(int idx) const {
        return size_t(idx) < by_id.size() ? by_id.at(idx) : 0;
    }
    const PHV::Field *field(const cstring &) const;
    const PHV::Field *field(const IR::Expression *, le_bitrange *bits = 0) const;
    const PHV::Field *field(const IR::Member *, le_bitrange *bits = 0) const;
    PHV::Field *field(int idx) { return (size_t)idx < by_id.size() ? by_id.at(idx) : 0; }
    PHV::Field *field(const cstring &name) {
        return const_cast<PHV::Field *>(const_cast<const PhvInfo *>(this)->field(name));
    }
    PHV::Field *field(const IR::Expression *e, le_bitrange *bits = 0) {
        return const_cast<PHV::Field *>(const_cast<const PhvInfo *>(this)->field(e, bits));
    }
    PHV::Field *field(const IR::Member *fr, le_bitrange *bits = 0) {
        return const_cast<PHV::Field *>(const_cast<const PhvInfo *>(this)->field(fr, bits));
    }
    bool has_struct_info(cstring name) const;
    void get_hdr_fields(cstring name_, ordered_set<const PHV::Field *> &flds) const;
    cstring full_hdr_name(const cstring &name) const;
    const PhvInfo::StructInfo *hdr(const cstring &name_) const;
 
    const StructInfo struct_info(cstring name) const;
    const StructInfo struct_info(const IR::HeaderRef *hr) const {
        return struct_info(hr->toString());
    }
    const std::map<cstring, PHV::Field> &get_all_fields() const { return all_fields; }
    size_t num_fields() const { return all_fields.size(); }
    const IR::TempVar *getTempVar(const PHV::Field *f) const;
 
    PHV::Field *add(cstring fieldName, gress_t gress, int size, int offset, bool isMetadata,
                    bool isPOV, bool bridged = false, bool isPad = false,
                    bool isOverlayable = false, bool isFlexible = false,
                    bool isFixedSizeHeader = false,
                    std::optional<Util::SourceInfo> srcInfo = std::nullopt);
 
    PHV::Field *create_dummy_padding(size_t sz, gress_t gress, bool overlayable = true);
 
    std::vector<PHV::AllocSlice> get_alloc(const IR::Expression *f,
                                           const PHV::AllocContext *ctxt = nullptr,
                                           const PHV::FieldUse *use = nullptr) const;
 
    std::vector<PHV::AllocSlice> get_alloc(const PHV::Field *phv_field, le_bitrange *bits = nullptr,
                                           const PHV::AllocContext *ctxt = nullptr,
                                           const PHV::FieldUse *use = nullptr) const;
 
    iterator<safe_vector<PHV::Field *>::iterator> begin() { return by_id.begin(); }
    iterator<safe_vector<PHV::Field *>::iterator> end() { return by_id.end(); }
    iterator<safe_vector<PHV::Field *>::const_iterator> begin() const { return by_id.begin(); }
    iterator<safe_vector<PHV::Field *>::const_iterator> end() const { return by_id.end(); }
 
    bool alloc_done() const { return alloc_done_; }
    bool trivial_alloc() const { return trivial_alloc_; }
    void set_done(bool trivial = false) {
        alloc_done_ = true;
        trivial_alloc_ = trivial;
    }
 
    void clear_container_to_fields() { container_to_fields.clear(); }
    void add_container_to_field_entry(const PHV::Container c, const PHV::Field *f);
 
    const ordered_set<const PHV::Field *> &fields_in_container(const PHV::Container c) const;
 
    std::vector<PHV::AllocSlice> get_slices_in_container(const PHV::Container c) const;
 
    std::vector<PHV::AllocSlice> get_slices_in_container(const PHV::Container c,
                                                         const PHV::AllocContext *ctxt,
                                                         const PHV::FieldUse *use) const;
 
    bitvec bits_allocated(const PHV::Container, const PHV::AllocContext *ctxt = nullptr,
                          const PHV::FieldUse *use = nullptr) const;
 
    bitvec bits_allocated(const PHV::Container container, const IR::MAU::Table *ctxt,
                          const PHV::FieldUse *use = nullptr) const {
        return bits_allocated(container, PHV::AllocContext::of_unit(ctxt), use);
    }
 
    bitvec bits_allocated(const PHV::Container, const PHV::Field *field,
                          const PHV::AllocContext *ctxt = nullptr,
                          const PHV::FieldUse *use = nullptr) const;
 
    bitvec bits_allocated(const PHV::Container container, const PHV::Field *field,
                          const IR::MAU::Table *ctxt, const PHV::FieldUse *use = nullptr) const {
        return bits_allocated(container, field, PHV::AllocContext::of_unit(ctxt), use);
    }
 
    bitvec bits_allocated(const PHV::Container, const ordered_set<const PHV::Field *> &,
                          const PHV::AllocContext *ctxt = nullptr,
                          const PHV::FieldUse *use = nullptr) const;
 
    bitvec bits_allocated(const PHV::Container container,
                          const ordered_set<const PHV::Field *> &fields, const IR::MAU::Table *ctxt,
                          const PHV::FieldUse *use = nullptr) const {
        return bits_allocated(container, fields, PHV::AllocContext::of_unit(ctxt), use);
    }
 
    std::optional<cstring> get_alias_name(const IR::Expression *expr) const;
 
    void addAliasMapEntry(const PHV::Field *f1, const PHV::Field *f2) {
        if (aliasMap.count(f1))
            BUG_CHECK(aliasMap[f1] == f2, "Multiple aliases with the same field found");
        aliasMap[f1] = f2;
    }
 
    void addExternalNameMapEntry(PHV::Field *f, cstring externalName) {
        externalNameMap[externalName] = f;
    }
 
    const ordered_map<const PHV::Field *, const PHV::Field *> &getAliasMap() const {
        return aliasMap;
    }
 
    const PHV::Field *getAliasDestination(const PHV::Field *f) const {
        if (aliasMap.count(f)) return aliasMap.at(f);
        return nullptr;
    }
 
    const std::set<PHV::Container> &getZeroContainers(gress_t gr) const {
        return zeroContainers[gr];
    }
 
    void addZeroContainer(gress_t gr, PHV::Container c) {
        zeroContainers[gr].insert(c);
        BUG_CHECK(zeroContainers[gr].size() <= 1,
                  "Only two zero containers allowed: one for each gress");
    }
 
    void addMetadataDependency(const IR::MAU::Table *t1, const IR::MAU::Table *t2,
                               const PHV::FieldSlice *slice = nullptr) {
        metadataDeps[t1->name].insert(t2->name);
        reverseMetadataDeps[t2->name].insert(t1->name);
        if (slice) {
            auto table_pair = std::make_pair(t1->name, t2->name);
            if (metadataDepFields.emplace(table_pair, slice).second) {
                LOG5(" Adding tables " << t1->name << " --> " << t2->name
                                       << " with metadata dependent field " << slice);
            }
        }
    }
 
    const ordered_set<cstring> getReverseMetadataDeps(const IR::MAU::Table *t) const {
        static ordered_set<cstring> emptySet;
        if (!reverseMetadataDeps.count(t->name)) return emptySet;
        return reverseMetadataDeps.at(t->name);
    }
 
    const ordered_map<cstring, ordered_set<cstring>> &getMetadataDeps() const {
        return metadataDeps;
    }
 
    const ordered_map<cstring, ordered_set<cstring>> &getReverseMetadataDeps() const {
        return reverseMetadataDeps;
    }
 
    const ordered_map<tpair, const PHV::FieldSlice *> &getMetadataDepFields() const {
        return metadataDepFields;
    }
 
    typedef ordered_map<PHV::Container, std::vector<PHV::AllocSlice>> ContainterToSliceMap;
    ContainterToSliceMap getContainerToSlicesMap(
        std::function<bool(const PHV::Field *)> *f = nullptr,
        std::function<bool(const PHV::AllocSlice *)> *s = nullptr) const;
};
 
struct CollectPhvInfo : public PassManager {
    explicit CollectPhvInfo(PhvInfo &phv);
};
 
class CollectExtractedTogetherFields : public Inspector {
 private:
    PhvInfo &phv_i;
    bool preorder(const IR::BFN::ParserState *state) override;
 
 public:
    explicit CollectExtractedTogetherFields(PhvInfo &p) : phv_i(p) {}
};
 
struct MapFieldToParserStates : public Inspector {
    const PhvInfo &phv_i;
 
    ordered_map<const PHV::Field *, ordered_set<const IR::BFN::ParserState *>>
        field_to_parser_states;
 
    ordered_map<const PHV::Field *, ordered_set<const IR::BFN::ParserPrimitive *>> field_to_writes;
 
    ordered_map<PHV::Container, ordered_set<const IR::BFN::ParserState *>>
        container_to_parser_states;
 
    ordered_map<PHV::Container, ordered_set<const IR::BFN::ParserPrimitive *>> container_to_writes;
 
    ordered_map<const IR::BFN::ParserPrimitive *, const IR::BFN::ParserState *> write_to_state;
 
    std::map<const IR::BFN::ParserState *, const IR::BFN::Parser *> state_to_parser;
 
    ordered_map<const IR::BFN::ParserState *, ordered_set<const IR::BFN::ParserPrimitive *>>
        state_to_writes;
 
    explicit MapFieldToParserStates(const PhvInfo &phv) : phv_i(phv) {}
 
    profile_t init_apply(const IR::Node *root) override {
        field_to_parser_states.clear();
        field_to_writes.clear();
        container_to_parser_states.clear();
        container_to_writes.clear();
        write_to_state.clear();
        state_to_parser.clear();
        state_to_writes.clear();
        return Inspector::init_apply(root);
    }
 
    bool preorder(const IR::BFN::ParserChecksumWritePrimitive *checksum) override {
        if (auto dest = checksum->getWriteDest()) add_field(dest->field, checksum);
        return true;
    }
 
    bool preorder(const IR::BFN::Extract *extract) override {
        if (auto lval = extract->dest->to<IR::BFN::FieldLVal>()) add_field(lval->field, extract);
        return true;
    }
 
 private:
    void add_field(const IR::Expression *field, const IR::BFN::ParserPrimitive *prim) {
        if (auto *f = phv_i.field(field)) {
            auto state = findContext<IR::BFN::ParserState>();
            auto parser = findContext<IR::BFN::Parser>();
 
            field_to_parser_states[f].insert(state);
            state_to_parser[state] = parser;
 
            field_to_writes[f].insert(prim);
            write_to_state[prim] = state;
            state_to_writes[state].insert(prim);
 
            if (phv_i.alloc_done()) {
                PHV::FieldUse use(PHV::FieldUse::WRITE);
                for (auto &alloc : phv_i.get_alloc(field, PHV::AllocContext::PARSER, &use)) {
                    auto cont = alloc.container();
                    container_to_parser_states[cont].insert(state);
                    container_to_writes[cont].insert(prim);
                }
            }
        }
    }
};
 
void dump(const PhvInfo *);
void dump(const PHV::Field *);
 
std::ostream &operator<<(std::ostream &, const ordered_set<PHV::Field *> &);
std::ostream &operator<<(std::ostream &, const ordered_set<const PHV::Field *> &);
std::ostream &operator<<(std::ostream &, const PhvInfo &);
std::ostream &operator<<(std::ostream &, const PHV::FieldAccessType &);
std::ostream &operator<<(std::ostream &, const PhvInfo::SameContainerAllocConstraint &);
std::ostream &operator<<(std::ostream &, const PhvInfo::SameContainerAllocConstraint::FieldBit &);
 
namespace PHV {
 
std::ostream &operator<<(std::ostream &, const PHV::FieldSlice &sl);
std::ostream &operator<<(std::ostream &, const PHV::FieldSlice *sl);
 
}  // namespace PHV
 
// These overloads must be declared directly in `namespace std` to work around
// ADL limitations for lookup of names in sibling namespaces.
namespace std {
ostream &operator<<(ostream &, const list<::PHV::Field *> &);
ostream &operator<<(ostream &, const set<const ::PHV::Field *> &);
}  // namespace std
//
#endif /* BF_P4C_PHV_PHV_FIELDS_H_ */