check_header_alignment.h

 
#ifndef BF_P4C_MIDEND_CHECK_HEADER_ALIGNMENT_H_
#define BF_P4C_MIDEND_CHECK_HEADER_ALIGNMENT_H_
 
#include "backends/tofino/bf-p4c/midend/type_checker.h"
#include "frontends/common/resolveReferences/resolveReferences.h"
#include "frontends/p4/methodInstance.h"
#include "frontends/p4/typeMap.h"
#include "ir/ir.h"
 
namespace P4 {
class TypeMap;
class ReferenceMap;
}  // namespace P4
 
namespace BFN {

class CheckPadAssignment final : public Inspector {
 private:
    bool preorder(const IR::AssignmentStatement *statement) override;
 
 public:
    CheckPadAssignment() {}
};

class CheckHeaderAlignment final : public Inspector {
    P4::TypeMap *typeMap;
 
 private:
    bool preorder(const IR::Type_Header *header) override;
 
 public:
    explicit CheckHeaderAlignment(P4::ReferenceMap *, P4::TypeMap *typeMap) : typeMap(typeMap) {}
};
 
using HeaderTypeMap = ordered_map<cstring, const IR::Type_Header *>;
using HeaderToPad = std::unordered_set<cstring>;
using ResubmitHeaders = std::unordered_set<cstring>;
 
class FindPaddingCandidate : public Inspector {
    P4::ReferenceMap *refMap;
    P4::TypeMap *typeMap;
    HeaderToPad *headers_to_pad;
    ResubmitHeaders *resubmit_headers;
    HeaderTypeMap *all_header_types;
 
 public:
    std::vector<cstring> find_headers_to_pad(P4::MethodInstance *mi);
    std::vector<const IR::Type_StructLike *> find_all_headers(P4::MethodInstance *mi);
    void check_mirror(P4::MethodInstance *mi);
    void check_digest(P4::MethodInstance *mi);
    void check_resubmit(P4::MethodInstance *mi);
    bool preorder(const IR::MethodCallExpression *expr) override;
    bool preorder(const IR::Type_Header *) override;
    explicit FindPaddingCandidate(P4::ReferenceMap *refMap, P4::TypeMap *typeMap,
                                  HeaderToPad *headers_to_pad, ResubmitHeaders *resubmit_headers,
                                  HeaderTypeMap *all_header_types)
        : refMap(refMap),
          typeMap(typeMap),
          headers_to_pad(headers_to_pad),
          resubmit_headers(resubmit_headers),
          all_header_types(all_header_types) {}
};
 
class AddPaddingFields : public Transform {
    P4::TypeMap *typeMap;
    HeaderToPad *headers_to_pad;
    ResubmitHeaders *resubmit_headers;
    HeaderTypeMap *all_header_types;
 
 public:
    explicit AddPaddingFields(P4::ReferenceMap *, P4::TypeMap *typeMap, HeaderToPad *headers_to_pad,
                              ResubmitHeaders *resubmit_headers, HeaderTypeMap *all_header_types)
        : typeMap(typeMap),
          headers_to_pad(headers_to_pad),
          resubmit_headers(resubmit_headers),
          all_header_types(all_header_types) {}
 
    const IR::Node *preorder(IR::Type_Header *st) override;
    const IR::Node *preorder(IR::StructExpression *) override;
};
 
// This pass transforms all resubmit headers from Type_Header to Type_FixedSizeHeader
class TransformResubmitHeaders : public Transform {
    ResubmitHeaders *resubmit_headers;
 
 public:
    explicit TransformResubmitHeaders(ResubmitHeaders *resubmit_headers)
        : resubmit_headers(resubmit_headers) {}
    const IR::Node *preorder(IR::Type_Header *) override;
};
 
class PadFlexibleField : public PassManager {
    // headers used in mirror, resubmit and digest
    HeaderToPad headers_to_pad;
    // all header types before padding is added.
    HeaderTypeMap all_header_types;
    ResubmitHeaders resubmit_headers;
 
 public:
    PadFlexibleField(P4::ReferenceMap *refMap, P4::TypeMap *typeMap) {
        addPasses({
            new FindPaddingCandidate(refMap, typeMap, &headers_to_pad, &resubmit_headers,
                                     &all_header_types),
            new AddPaddingFields(refMap, typeMap, &headers_to_pad, &resubmit_headers,
                                 &all_header_types),
            new TransformResubmitHeaders(&resubmit_headers),
            // After padding the TypeInference might
            // change new ListExpressions to StructExpressions
            new P4::ClearTypeMap(typeMap),
            new P4::ResolveReferences(refMap),
            new BFN::TypeInference(typeMap, false),
            new P4::ClearTypeMap(typeMap),
            new BFN::TypeChecking(refMap, typeMap, true),
            new CheckHeaderAlignment(refMap, typeMap),
            new CheckPadAssignment(),
        });
        setName("PadFlexibleField");
    }
};
 
}  // namespace BFN
 
#endif /* BF_P4C_MIDEND_CHECK_HEADER_ALIGNMENT_H_ */