elim_unused.h

 
#ifndef BF_P4C_COMMON_ELIM_UNUSED_H_
#define BF_P4C_COMMON_ELIM_UNUSED_H_
 
#include "field_defuse.h"
 
using namespace P4;
 
class ReplaceMember : public Transform {
    const IR::BFN::AliasMember *preorder(IR::BFN::AliasMember *m) { return m; }
    const IR::BFN::AliasMember *preorder(IR::Member *m) { return new IR::BFN::AliasMember(m, m); }
};
 
class ElimUnused : public PassManager {
    const PhvInfo &phv;
    FieldDefUse &defuse;
    std::set<cstring> &zeroInitFields;
 
    class Instructions;
    class CollectEmptyTables;
    class Tables;
    class Headers;
 
 public:
    ElimUnused(const PhvInfo &phv, FieldDefUse &defuse, std::set<cstring> &zeroInitFields);
};
 
class AbstractElimUnusedInstructions : public Transform {
 protected:
    const FieldDefUse &defuse;
 
    std::set<cstring> eliminated;
 
    const IR::MAU::StatefulAlu *preorder(IR::MAU::StatefulAlu *salu) override {
        // Don't go through these.
        prune();
        return salu;
    }
 
    const IR::GlobalRef *preorder(IR::GlobalRef *gr) override {
        // Don't go through these.
        prune();
        return gr;
    }
 
    virtual bool elim_extract(const IR::BFN::Unit *unit, const IR::BFN::Extract *extract) = 0;
 
    const IR::BFN::Extract *preorder(IR::BFN::Extract *extract) override;
    const IR::BFN::FieldLVal *preorder(IR::BFN::FieldLVal *lval) override;
 
    explicit AbstractElimUnusedInstructions(const FieldDefUse &defuse) : defuse(defuse) {}
};
 
#endif /* BF_P4C_COMMON_ELIM_UNUSED_H_ */