parserControlFlow.h

/*
 * Copyright 2016 VMware, Inc.
 * SPDX-FileCopyrightText: 2016 VMware, Inc.
 *
 * SPDX-License-Identifier: Apache-2.0
 */
 
#ifndef FRONTENDS_P4_PARSERCONTROLFLOW_H_
#define FRONTENDS_P4_PARSERCONTROLFLOW_H_
 
#include "frontends/p4/moveDeclarations.h"
#include "frontends/p4/simplify.h"
#include "frontends/p4/uniqueNames.h"
#include "ir/ir.h"
 
namespace P4 {

 
class DoRemoveParserControlFlow : public Transform {
    MinimalNameGenerator nameGen;
 
 public:
    DoRemoveParserControlFlow() { setName("DoRemoveParserControlFlow"); }
    const IR::Node *postorder(IR::ParserState *state) override;
    Visitor::profile_t init_apply(const IR::Node *node) override;
};

class RemoveParserControlFlow : public PassRepeated {
 public:
    explicit RemoveParserControlFlow(TypeMap *typeMap) : PassRepeated({}) {
        passes.emplace_back(new DoRemoveParserControlFlow());
        passes.emplace_back(new SimplifyControlFlow(typeMap, false));
        setName("RemoveParserControlFlow");
    }
};

class IfInParser : public Inspector {
    bool *found;
 
 public:
    explicit IfInParser(bool *found) : found(found) {
        CHECK_NULL(found);
        setName("IfInParser");
    }
    void postorder(const IR::IfStatement *) override {
        if (isInContext<IR::P4Parser>()) *found = true;
    }
};

class RemoveParserIfs : public PassManager {
    bool found = false;
 
 public:
    explicit RemoveParserIfs(TypeMap *typeMap) {
        passes.push_back(new IfInParser(&found));
        passes.push_back(
            new PassIf([this] { return found; },
                       {                    // only do this if we found an 'if' in a parser
                        new UniqueNames(),  // Give each local declaration a unique internal name
                        new MoveDeclarations(true),  // Move all local declarations to the beginning
                        new RemoveParserControlFlow(typeMap)}));
    }
};
 
}  // namespace P4
 
#endif /* FRONTENDS_P4_PARSERCONTROLFLOW_H_ */