clang-tools-extra/clangd/DecisionForest.cpp

   1 //===--- DecisionForest.cpp --------------------------------------*- C++-*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "Features.inc"
  10
  11 #if !CLANGD_DECISION_FOREST
  12 #include "Quality.h"
  13 #include <cstdlib>
  14
  15 namespace clang {
  16 namespace clangd {
  17 DecisionForestScores
  18 evaluateDecisionForest(const SymbolQualitySignals &Quality,
  19                        const SymbolRelevanceSignals &Relevance, float Base) {
  20   llvm::errs() << "Clangd was compiled without decision forest support.\n";
  21   std::abort();
  22 }
  23
  24 } // namespace clangd
  25 } // namespace clang
  26
  27 #else // !CLANGD_DECISION_FOREST
  28
  29 #include "CompletionModel.h"
  30 #include "Quality.h"
  31 #include <cmath>
  32
  33 namespace clang {
  34 namespace clangd {
  35
  36 DecisionForestScores
  37 evaluateDecisionForest(const SymbolQualitySignals &Quality,
  38                        const SymbolRelevanceSignals &Relevance, float Base) {
  39   Example E;
  40   E.setIsDeprecated(Quality.Deprecated);
  41   E.setIsReservedName(Quality.ReservedName);
  42   E.setIsImplementationDetail(Quality.ImplementationDetail);
  43   E.setNumReferences(Quality.References);
  44   E.setSymbolCategory(Quality.Category);
  45
  46   SymbolRelevanceSignals::DerivedSignals Derived =
  47       Relevance.calculateDerivedSignals();
  48   int NumMatch = 0;
  49   if (Relevance.ContextWords) {
  50     for (const auto &Word : Relevance.ContextWords->keys()) {
  51       if (Relevance.Name.contains_insensitive(Word)) {
  52         ++NumMatch;
  53       }
  54     }
  55   }
  56   E.setIsNameInContext(NumMatch > 0);
  57   E.setNumNameInContext(NumMatch);
  58   E.setFractionNameInContext(
  59       Relevance.ContextWords && !Relevance.ContextWords->empty()
  60           ? NumMatch * 1.0 / Relevance.ContextWords->size()
  61           : 0);
  62   E.setIsInBaseClass(Relevance.InBaseClass);
  63   E.setFileProximityDistanceCost(Derived.FileProximityDistance);
  64   E.setSemaFileProximityScore(Relevance.SemaFileProximityScore);
  65   E.setSymbolScopeDistanceCost(Derived.ScopeProximityDistance);
  66   E.setSemaSaysInScope(Relevance.SemaSaysInScope);
  67   E.setScope(Relevance.Scope);
  68   E.setContextKind(Relevance.Context);
  69   E.setIsInstanceMember(Relevance.IsInstanceMember);
  70   E.setHadContextType(Relevance.HadContextType);
  71   E.setHadSymbolType(Relevance.HadSymbolType);
  72   E.setTypeMatchesPreferred(Relevance.TypeMatchesPreferred);
  73
  74   DecisionForestScores Scores;
  75   // Exponentiating DecisionForest prediction makes the score of each tree a
  76   // multiplciative boost (like NameMatch). This allows us to weigh the
  77   // prediction score and NameMatch appropriately.
  78   Scores.ExcludingName = pow(Base, Evaluate(E));
  79   // Following cases are not part of the generated training dataset:
  80   //  - Symbols with `NeedsFixIts`.
  81   //  - Forbidden symbols.
  82   //  - Keywords: Dataset contains only macros and decls.
  83   if (Relevance.NeedsFixIts)
  84     Scores.ExcludingName *= 0.5;
  85   if (Relevance.Forbidden)
  86     Scores.ExcludingName *= 0;
  87   if (Quality.Category == SymbolQualitySignals::Keyword)
  88     Scores.ExcludingName *= 4;
  89
  90   // NameMatch should be a multiplier on total score to support rescoring.
  91   Scores.Total = Relevance.NameMatch * Scores.ExcludingName;
  92   return Scores;
  93 }
  94
  95 } // namespace clangd
  96 } // namespace clang
  97
  98 #endif // !CLANGD_DECISION_FOREST