1 files changed, 457 insertions, 0 deletions
diff --git a/clang/lib/ASTMatchers/Dynamic/VariantValue.cpp b/clang/lib/ASTMatchers/Dynamic/VariantValue.cpp
new file mode 100644
index 000000000000..118ca2a41cb1
--- /dev/null
+++ b/clang/lib/ASTMatchers/Dynamic/VariantValue.cpp
@@ -0,0 +1,457 @@
+//===--- VariantValue.cpp - Polymorphic value type -*- C++ -*-===/
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// Polymorphic value type.
+///
+//===----------------------------------------------------------------------===//
+
+#include "clang/ASTMatchers/Dynamic/VariantValue.h"
+#include "clang/Basic/LLVM.h"
+#include "llvm/ADT/STLExtras.h"
+
+namespace clang {
+namespace ast_matchers {
+namespace dynamic {
+
+std::string ArgKind::asString() const {
+  switch (getArgKind()) {
+  case AK_Matcher:
+    return (Twine("Matcher<") + MatcherKind.asStringRef() + ">").str();
+  case AK_Boolean:
+    return "boolean";
+  case AK_Double:
+    return "double";
+  case AK_Unsigned:
+    return "unsigned";
+  case AK_String:
+    return "string";
+  }
+  llvm_unreachable("unhandled ArgKind");
+}
+
+bool ArgKind::isConvertibleTo(ArgKind To, unsigned *Specificity) const {
+  if (K != To.K)
+    return false;
+  if (K != AK_Matcher) {
+    if (Specificity)
+      *Specificity = 1;
+    return true;
+  }
+  unsigned Distance;
+  if (!MatcherKind.isBaseOf(To.MatcherKind, &Distance))
+    return false;
+
+  if (Specificity)
+    *Specificity = 100 - Distance;
+  return true;
+}
+
+bool
+VariantMatcher::MatcherOps::canConstructFrom(const DynTypedMatcher &Matcher,
+                                             bool &IsExactMatch) const {
+  IsExactMatch = Matcher.getSupportedKind().isSame(NodeKind);
+  return Matcher.canConvertTo(NodeKind);
+}
+
+llvm::Optional<DynTypedMatcher>
+VariantMatcher::MatcherOps::constructVariadicOperator(
+    DynTypedMatcher::VariadicOperator Op,
+    ArrayRef<VariantMatcher> InnerMatchers) const {
+  std::vector<DynTypedMatcher> DynMatchers;
+  for (const auto &InnerMatcher : InnerMatchers) {
+    // Abort if any of the inner matchers can't be converted to
+    // Matcher<T>.
+    if (!InnerMatcher.Value)
+      return llvm::None;
+    llvm::Optional<DynTypedMatcher> Inner =
+        InnerMatcher.Value->getTypedMatcher(*this);
+    if (!Inner)
+      return llvm::None;
+    DynMatchers.push_back(*Inner);
+  }
+  return DynTypedMatcher::constructVariadic(Op, NodeKind, DynMatchers);
+}
+
+VariantMatcher::Payload::~Payload() {}
+
+class VariantMatcher::SinglePayload : public VariantMatcher::Payload {
+public:
+  SinglePayload(const DynTypedMatcher &Matcher) : Matcher(Matcher) {}
+
+  llvm::Optional<DynTypedMatcher> getSingleMatcher() const override {
+    return Matcher;
+  }
+
+  std::string getTypeAsString() const override {
+    return (Twine("Matcher<") + Matcher.getSupportedKind().asStringRef() + ">")
+        .str();
+  }
+
+  llvm::Optional<DynTypedMatcher>
+  getTypedMatcher(const MatcherOps &Ops) const override {
+    bool Ignore;
+    if (Ops.canConstructFrom(Matcher, Ignore))
+      return Matcher;
+    return llvm::None;
+  }
+
+  bool isConvertibleTo(ast_type_traits::ASTNodeKind Kind,
+                       unsigned *Specificity) const override {
+    return ArgKind(Matcher.getSupportedKind())
+        .isConvertibleTo(Kind, Specificity);
+  }
+
+private:
+  const DynTypedMatcher Matcher;
+};
+
+class VariantMatcher::PolymorphicPayload : public VariantMatcher::Payload {
+public:
+  PolymorphicPayload(std::vector<DynTypedMatcher> MatchersIn)
+      : Matchers(std::move(MatchersIn)) {}
+
+  ~PolymorphicPayload() override {}
+
+  llvm::Optional<DynTypedMatcher> getSingleMatcher() const override {
+    if (Matchers.size() != 1)
+      return llvm::Optional<DynTypedMatcher>();
+    return Matchers[0];
+  }
+
+  std::string getTypeAsString() const override {
+    std::string Inner;
+    for (size_t i = 0, e = Matchers.size(); i != e; ++i) {
+      if (i != 0)
+        Inner += "|";
+      Inner += Matchers[i].getSupportedKind().asStringRef();
+    }
+    return (Twine("Matcher<") + Inner + ">").str();
+  }
+
+  llvm::Optional<DynTypedMatcher>
+  getTypedMatcher(const MatcherOps &Ops) const override {
+    bool FoundIsExact = false;
+    const DynTypedMatcher *Found = nullptr;
+    int NumFound = 0;
+    for (size_t i = 0, e = Matchers.size(); i != e; ++i) {
+      bool IsExactMatch;
+      if (Ops.canConstructFrom(Matchers[i], IsExactMatch)) {
+        if (Found) {
+          if (FoundIsExact) {
+            assert(!IsExactMatch && "We should not have two exact matches.");
+            continue;
+          }
+        }
+        Found = &Matchers[i];
+        FoundIsExact = IsExactMatch;
+        ++NumFound;
+      }
+    }
+    // We only succeed if we found exactly one, or if we found an exact match.
+    if (Found && (FoundIsExact || NumFound == 1))
+      return *Found;
+    return llvm::None;
+  }
+
+  bool isConvertibleTo(ast_type_traits::ASTNodeKind Kind,
+                       unsigned *Specificity) const override {
+    unsigned MaxSpecificity = 0;
+    for (const DynTypedMatcher &Matcher : Matchers) {
+      unsigned ThisSpecificity;
+      if (ArgKind(Matcher.getSupportedKind())
+              .isConvertibleTo(Kind, &ThisSpecificity)) {
+        MaxSpecificity = std::max(MaxSpecificity, ThisSpecificity);
+      }
+    }
+    if (Specificity)
+      *Specificity = MaxSpecificity;
+    return MaxSpecificity > 0;
+  }
+
+  const std::vector<DynTypedMatcher> Matchers;
+};
+
+class VariantMatcher::VariadicOpPayload : public VariantMatcher::Payload {
+public:
+  VariadicOpPayload(DynTypedMatcher::VariadicOperator Op,
+                    std::vector<VariantMatcher> Args)
+      : Op(Op), Args(std::move(Args)) {}
+
+  llvm::Optional<DynTypedMatcher> getSingleMatcher() const override {
+    return llvm::Optional<DynTypedMatcher>();
+  }
+
+  std::string getTypeAsString() const override {
+    std::string Inner;
+    for (size_t i = 0, e = Args.size(); i != e; ++i) {
+      if (i != 0)
+        Inner += "&";
+      Inner += Args[i].getTypeAsString();
+    }
+    return Inner;
+  }
+
+  llvm::Optional<DynTypedMatcher>
+  getTypedMatcher(const MatcherOps &Ops) const override {
+    return Ops.constructVariadicOperator(Op, Args);
+  }
+
+  bool isConvertibleTo(ast_type_traits::ASTNodeKind Kind,
+                       unsigned *Specificity) const override {
+    for (const VariantMatcher &Matcher : Args) {
+      if (!Matcher.isConvertibleTo(Kind, Specificity))
+        return false;
+    }
+    return true;
+  }
+
+private:
+  const DynTypedMatcher::VariadicOperator Op;
+  const std::vector<VariantMatcher> Args;
+};
+
+VariantMatcher::VariantMatcher() {}
+
+VariantMatcher VariantMatcher::SingleMatcher(const DynTypedMatcher &Matcher) {
+  return VariantMatcher(std::make_shared<SinglePayload>(Matcher));
+}
+
+VariantMatcher
+VariantMatcher::PolymorphicMatcher(std::vector<DynTypedMatcher> Matchers) {
+  return VariantMatcher(
+      std::make_shared<PolymorphicPayload>(std::move(Matchers)));
+}
+
+VariantMatcher VariantMatcher::VariadicOperatorMatcher(
+    DynTypedMatcher::VariadicOperator Op,
+    std::vector<VariantMatcher> Args) {
+  return VariantMatcher(
+      std::make_shared<VariadicOpPayload>(Op, std::move(Args)));
+}
+
+llvm::Optional<DynTypedMatcher> VariantMatcher::getSingleMatcher() const {
+  return Value ? Value->getSingleMatcher() : llvm::Optional<DynTypedMatcher>();
+}
+
+void VariantMatcher::reset() { Value.reset(); }
+
+std::string VariantMatcher::getTypeAsString() const {
+  if (Value) return Value->getTypeAsString();
+  return "<Nothing>";
+}
+
+VariantValue::VariantValue(const VariantValue &Other) : Type(VT_Nothing) {
+  *this = Other;
+}
+
+VariantValue::VariantValue(bool Boolean) : Type(VT_Nothing) {
+  setBoolean(Boolean);
+}
+
+VariantValue::VariantValue(double Double) : Type(VT_Nothing) {
+  setDouble(Double);
+}
+
+VariantValue::VariantValue(unsigned Unsigned) : Type(VT_Nothing) {
+  setUnsigned(Unsigned);
+}
+
+VariantValue::VariantValue(StringRef String) : Type(VT_Nothing) {
+  setString(String);
+}
+
+VariantValue::VariantValue(const VariantMatcher &Matcher) : Type(VT_Nothing) {
+  setMatcher(Matcher);
+}
+
+VariantValue::~VariantValue() { reset(); }
+
+VariantValue &VariantValue::operator=(const VariantValue &Other) {
+  if (this == &Other) return *this;
+  reset();
+  switch (Other.Type) {
+  case VT_Boolean:
+    setBoolean(Other.getBoolean());
+    break;
+  case VT_Double:
+    setDouble(Other.getDouble());
+    break;
+  case VT_Unsigned:
+    setUnsigned(Other.getUnsigned());
+    break;
+  case VT_String:
+    setString(Other.getString());
+    break;
+  case VT_Matcher:
+    setMatcher(Other.getMatcher());
+    break;
+  case VT_Nothing:
+    Type = VT_Nothing;
+    break;
+  }
+  return *this;
+}
+
+void VariantValue::reset() {
+  switch (Type) {
+  case VT_String:
+    delete Value.String;
+    break;
+  case VT_Matcher:
+    delete Value.Matcher;
+    break;
+  // Cases that do nothing.
+  case VT_Boolean:
+  case VT_Double:
+  case VT_Unsigned:
+  case VT_Nothing:
+    break;
+  }
+  Type = VT_Nothing;
+}
+
+bool VariantValue::isBoolean() const {
+  return Type == VT_Boolean;
+}
+
+bool VariantValue::getBoolean() const {
+  assert(isBoolean());
+  return Value.Boolean;
+}
+
+void VariantValue::setBoolean(bool NewValue) {
+  reset();
+  Type = VT_Boolean;
+  Value.Boolean = NewValue;
+}
+
+bool VariantValue::isDouble() const {
+  return Type == VT_Double;
+}
+
+double VariantValue::getDouble() const {
+  assert(isDouble());
+  return Value.Double;
+}
+
+void VariantValue::setDouble(double NewValue) {
+  reset();
+  Type = VT_Double;
+  Value.Double = NewValue;
+}
+
+bool VariantValue::isUnsigned() const {
+  return Type == VT_Unsigned;
+}
+
+unsigned VariantValue::getUnsigned() const {
+  assert(isUnsigned());
+  return Value.Unsigned;
+}
+
+void VariantValue::setUnsigned(unsigned NewValue) {
+  reset();
+  Type = VT_Unsigned;
+  Value.Unsigned = NewValue;
+}
+
+bool VariantValue::isString() const {
+  return Type == VT_String;
+}
+
+const std::string &VariantValue::getString() const {
+  assert(isString());
+  return *Value.String;
+}
+
+void VariantValue::setString(StringRef NewValue) {
+  reset();
+  Type = VT_String;
+  Value.String = new std::string(NewValue);
+}
+
+bool VariantValue::isMatcher() const {
+  return Type == VT_Matcher;
+}
+
+const VariantMatcher &VariantValue::getMatcher() const {
+  assert(isMatcher());
+  return *Value.Matcher;
+}
+
+void VariantValue::setMatcher(const VariantMatcher &NewValue) {
+  reset();
+  Type = VT_Matcher;
+  Value.Matcher = new VariantMatcher(NewValue);
+}
+
+bool VariantValue::isConvertibleTo(ArgKind Kind, unsigned *Specificity) const {
+  switch (Kind.getArgKind()) {
+  case ArgKind::AK_Boolean:
+    if (!isBoolean())
+      return false;
+    *Specificity = 1;
+    return true;
+
+  case ArgKind::AK_Double:
+    if (!isDouble())
+      return false;
+    *Specificity = 1;
+    return true;
+
+  case ArgKind::AK_Unsigned:
+    if (!isUnsigned())
+      return false;
+    *Specificity = 1;
+    return true;
+
+  case ArgKind::AK_String:
+    if (!isString())
+      return false;
+    *Specificity = 1;
+    return true;
+
+  case ArgKind::AK_Matcher:
+    if (!isMatcher())
+      return false;
+    return getMatcher().isConvertibleTo(Kind.getMatcherKind(), Specificity);
+  }
+  llvm_unreachable("Invalid Type");
+}
+
+bool VariantValue::isConvertibleTo(ArrayRef<ArgKind> Kinds,
+                                   unsigned *Specificity) const {
+  unsigned MaxSpecificity = 0;
+  for (const ArgKind& Kind : Kinds) {
+    unsigned ThisSpecificity;
+    if (!isConvertibleTo(Kind, &ThisSpecificity))
+      continue;
+    MaxSpecificity = std::max(MaxSpecificity, ThisSpecificity);
+  }
+  if (Specificity && MaxSpecificity > 0) {
+    *Specificity = MaxSpecificity;
+  }
+  return MaxSpecificity > 0;
+}
+
+std::string VariantValue::getTypeAsString() const {
+  switch (Type) {
+  case VT_String: return "String";
+  case VT_Matcher: return getMatcher().getTypeAsString();
+  case VT_Boolean: return "Boolean";
+  case VT_Double: return "Double";
+  case VT_Unsigned: return "Unsigned";
+  case VT_Nothing: return "Nothing";
+  }
+  llvm_unreachable("Invalid Type");
+}
+
+} // end namespace dynamic
+} // end namespace ast_matchers
+} // end namespace clang