verilog/analysis/checkers/generate_label_rule.h

// Copyright 2017-2020 The Verible Authors.
//
// 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 VERIBLE_VERILOG_ANALYSIS_CHECKERS_GENERATE_LABEL_RULE_H_
#define VERIBLE_VERILOG_ANALYSIS_CHECKERS_GENERATE_LABEL_RULE_H_

#include <set>
#include <string>

#include "common/analysis/lint_rule_status.h"
#include "common/analysis/matcher/core_matchers.h"
#include "common/analysis/matcher/matcher.h"
#include "common/analysis/matcher/matcher_builders.h"
#include "common/analysis/syntax_tree_lint_rule.h"
#include "common/text/symbol.h"
#include "common/text/syntax_tree_context.h"
#include "verilog/CST/verilog_matchers.h"  // IWYU pragma: keep
#include "verilog/analysis/descriptions.h"

namespace verilog {
namespace analysis {

// GenerateLabelRule checks for unlabeled generate block statements.
//
// Examples violations:
// module
//   generate
//    if (TypeIsPosedge) begin // needs a label here
//      always @(posedge clk) foo <= bar;
//    end else begin // needs a label here
//      always @(negedge clk) foo <= bar;
//    end
//   endgenerate
// endmodule
//
class GenerateLabelRule : public verible::SyntaxTreeLintRule {
 public:
  using rule_type = verible::SyntaxTreeLintRule;
  static absl::string_view Name();

  // Returns the description of the rule implemented formatted for either the
  // helper flag or markdown depending on the parameter type.
  static std::string GetDescription(DescriptionType);

  void HandleSymbol(const verible::Symbol& symbol,
                    const verible::SyntaxTreeContext& context) override;

  verible::LintRuleStatus Report() const override;

 private:
  // Matches against generate blocks that do not have a label
  //
  // For example:
  //   if (TypeIsPosedge) begin
  //      always @(posedge clk) foo <= bar;
  //    end
  //
  const verible::matcher::Matcher matcher_ =
      NodekGenerateBlock(verible::matcher::Unless(HasBeginLabel()));

  // Link to style guide rule.
  static const char kTopic[];

  // Diagnostic message.
  static const char kMessage[];

  std::set<verible::LintViolation> violations_;
};

}  // namespace analysis
}  // namespace verilog

#endif  // VERIBLE_VERILOG_ANALYSIS_CHECKERS_GENERATE_LABEL_RULE_H_