Mangle value parameter markers and fix demangling value params

Author: Azoy

include/swift/AST/ASTDemangler.h

@@ -68,6 +68,15 @@ class ASTBuilder {
   /// For saving and restoring generic parameters.
   llvm::SmallVector<decltype(ParameterPacks), 2> ParameterPackStack;
 
+  /// The depth and index of each value parameter in the current generic
+  /// signature. We need this becasue the mangling for a type parameter
+  /// doesn't record whether it is a value or not; we find the correct
+  /// depth and index in this array, and use its value-ness.
+  llvm::SmallVector<std::tuple<std::pair<unsigned, unsigned>, Type>, 1> ValueParameters;
+
+  /// For saving and restoring generic parameters.
+  llvm::SmallVector<decltype(ValueParameters), 1> ValueParametersStack;
+
   /// This builder doesn't perform "on the fly" substitutions, so we preserve
   /// all pack expansions. We still need an active expansion stack though,
   /// for the dummy implementation of these methods:
@@ -93,6 +102,12 @@ class ASTBuilder {
     for (auto *paramTy : genericSig.getGenericParams()) {
       if (paramTy->isParameterPack())
         ParameterPacks.emplace_back(paramTy->getDepth(), paramTy->getIndex());
+
+      if (paramTy->isValue()) {
+        auto pair = std::make_pair(paramTy->getDepth(), paramTy->getIndex());
+        auto tuple = std::make_tuple(pair, paramTy->getValueType());
+        ValueParameters.emplace_back(tuple);
+      }
     }
   }
 

include/swift/Demangling/TypeDecoder.h

@@ -454,7 +454,8 @@ void decodeRequirement(
     BuilderType &Builder) {
   for (auto &child : *node) {
     if (child->getKind() == Demangle::Node::Kind::DependentGenericParamCount ||
-        child->getKind() == Demangle::Node::Kind::DependentGenericParamPackMarker)
+        child->getKind() == Demangle::Node::Kind::DependentGenericParamPackMarker ||
+        child->getKind() == Demangle::Node::Kind::DependentGenericParamValueMarker)
       continue;
 
     if (child->getNumChildren() != 2)

lib/AST/ASTDemangler.cpp

@@ -843,6 +843,11 @@ void ASTBuilder::pushGenericParams(ArrayRef<std::pair<unsigned, unsigned>> param
 void ASTBuilder::popGenericParams() {
   ParameterPacks = ParameterPackStack.back();
   ParameterPackStack.pop_back();
+
+  if (!ValueParametersStack.empty()) {
+    ValueParameters = ValueParametersStack.back();
+    ValueParametersStack.pop_back();
+  }
 }
 
 Type ASTBuilder::createGenericTypeParameterType(unsigned depth,
@@ -855,6 +860,17 @@ Type ASTBuilder::createGenericTypeParameterType(unsigned depth,
     }
   }
 
+  if (!ValueParameters.empty()) {
+    for (auto tuple : ValueParameters) {
+      auto pair = std::get<std::pair<unsigned, unsigned>>(tuple);
+      auto type = std::get<Type>(tuple);
+
+      if (pair.first == depth && pair.second == index) {
+        return GenericTypeParamType::getValue(depth, index, type, Ctx);
+      }
+    }
+  }
+
   return GenericTypeParamType::getType(depth, index, Ctx);
 }
 
@@ -1195,9 +1211,18 @@ CanGenericSignature ASTBuilder::demangleGenericSignature(
   // we introduce the parameter packs from the nominal's generic signature.
   ParameterPackStack.push_back(ParameterPacks);
   ParameterPacks.clear();
+
+  ValueParametersStack.push_back(ValueParameters);
+  ValueParameters.clear();
   for (auto *paramTy : baseGenericSig.getGenericParams()) {
     if (paramTy->isParameterPack())
       ParameterPacks.emplace_back(paramTy->getDepth(), paramTy->getIndex());
+
+    if (paramTy->isValue()) {
+      auto pair = std::make_pair(paramTy->getDepth(), paramTy->getIndex());
+      auto tuple = std::make_tuple(pair, paramTy->getValueType());
+      ValueParameters.emplace_back(tuple);
+    }
   }
   SWIFT_DEFER { popGenericParams(); };
 

lib/AST/ASTMangler.cpp

@@ -3611,10 +3611,17 @@ void ASTMangler::appendGenericSignatureParts(
   ArrayRef<Requirement> requirements = parts.requirements;
   ArrayRef<InverseRequirement> inverseRequirements = parts.inverses;
 
-  // Mangle which generic parameters are pack parameters.
+  // Mangle the kind for each generic parameter.
   for (auto param : params) {
+    // Regular type parameters have no marker.
+
     if (param->isParameterPack())
       appendOpWithGenericParamIndex("Rv", param);
+
+    if (param->isValue()) {
+      appendType(param->getValueType(), sig);
+      appendOpWithGenericParamIndex("RV", param);
+    }
   }
 
   // Mangle the requirements.

lib/Demangling/NodePrinter.cpp

@@ -1060,7 +1060,8 @@ class NodePrinter {
       auto child = Node->getChild(firstRequirement);
       if (child->getKind() == Node::Kind::Type)
         child = child->getChild(0);
-      if (child->getKind() != Node::Kind::DependentGenericParamPackMarker) {
+      if (child->getKind() != Node::Kind::DependentGenericParamPackMarker &&
+          child->getKind() != Node::Kind::DependentGenericParamValueMarker) {
         break;
       }
     }

lib/Demangling/Remangler.cpp

@@ -3969,9 +3969,10 @@ ManglingError Remangler::mangleNegativeInteger(Node *node, unsigned int depth) {
 
 ManglingError Remangler::mangleDependentGenericParamValueMarker(Node *node,
                                                                unsigned depth) {
-  DEMANGLER_ASSERT(node->getNumChildren() == 1, node);
-  DEMANGLER_ASSERT(node->getChild(0)->getKind() == Node::Kind::Type, node);
-  RETURN_IF_ERROR(mangleType(node->getChild(0)->getChild(1), depth + 1));
+  DEMANGLER_ASSERT(node->getNumChildren() == 2, node);
+  DEMANGLER_ASSERT(node->getChild(0)->getChild(0)->getKind() == Node::Kind::DependentGenericParamType, node);
+  DEMANGLER_ASSERT(node->getChild(1)->getKind() == Node::Kind::Type, node);
+  RETURN_IF_ERROR(mangleType(node->getChild(1), depth + 1));
   Buffer << "RV";
   mangleDependentGenericParamIndex(node->getChild(0)->getChild(0));
   return ManglingError::Success;