frontends/p4/frontend.h

/*
Copyright 2013-present Barefoot Networks, Inc.
 
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
 
    http://www.apache.org/licenses/LICENSE-2.0
 
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
 
#ifndef P4_FRONTEND_H_
#define P4_FRONTEND_H_
 
#include "../common/options.h"
#include "ir/ir.h"
#include "parseAnnotations.h"
#include "unusedDeclarations.h"
 
namespace P4 {
 
class ConstantFoldingPolicy;  // forward declare to avoid having to include

class FrontEndPolicy : public RemoveUnusedPolicy {
 public:
    virtual ~FrontEndPolicy() = default;

    virtual std::vector<DebugHook> getDebugHooks() const { return {}; }

    virtual ParseAnnotations *getParseAnnotations() const { return nullptr; }

    virtual bool removeOpAssign() const { return true; }

    // TODO: This should probably not be allowed to be skipped at all.
    virtual bool skipSideEffectOrdering() const { return false; }

    virtual bool foldInlinedFrom() const { return true; }

    virtual bool enableSubConstToAddTransform() const { return true; }

    virtual bool optimize(const CompilerOptions &options) const {
        return options.optimizationLevel > 0;
    }

    virtual ConstantFoldingPolicy *getConstantFoldingPolicy() const { return nullptr; }
};
 
class FrontEnd {
    FrontEndPolicy *policy;
    std::vector<DebugHook> hooks;
 
 public:
    FrontEnd() : FrontEnd(new FrontEndPolicy()) {}
    explicit FrontEnd(FrontEndPolicy *policy) : policy(policy), hooks(policy->getDebugHooks()) {}
 
    void addDebugHook(const DebugHook &hook) { hooks.push_back(hook); }
    // If p4c is run with option '--listFrontendPasses', outStream is used for printing passes names
    const IR::P4Program *run(const CompilerOptions &options, const IR::P4Program *program,
                             std::ostream *outStream = nullptr);
};
 
}  // namespace P4
 
#endif /* P4_FRONTEND_H_ */