[libc-commits] [libc] [libc] add support for function level attributes (PR #79891)

[Schrodinger ZHU Yifan via libc-commits]

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@@ -47,9 +51,133 @@ static std::string getTypeHdrName(const std::string &Name) {
 
 namespace llvm_libc {
 
-void writeAPIFromIndex(APIIndexer &G,
-                       std::vector<std::string> EntrypointNameList,
-                       llvm::raw_ostream &OS) {
+static AttributeStyle getAttributeStyle(llvm::Record *Instance) {
+  llvm::StringRef Style = Instance->getValueAsString("Style");
+  return llvm::StringSwitch<AttributeStyle>(Style)
+      .Case("cxx11", AttributeStyle::Cxx11)
+      .Case("gnu", AttributeStyle::Gnu)
+      .Case("declspec", AttributeStyle::Declspec)
+      .Default(AttributeStyle::Gnu);
+}
+
+static AttributeNamespace getAttributeNamespace(llvm::Record *Instance) {
+  llvm::StringRef Namespace = Instance->getValueAsString("Namespace");
+  return llvm::StringSwitch<AttributeNamespace>(Namespace)
+      .Case("clang", AttributeNamespace::Clang)
+      .Case("gnu", AttributeNamespace::Gnu)
+      .Default(AttributeNamespace::None);
+}
+
+using AttributeMap = llvm::DenseMap<llvm::StringRef, llvm::Record *>;
+
+template <class SpecMap, class FuncList>
+static AttributeMap collectAttributeMacros(const SpecMap &Spec,
+                                           const FuncList &Funcs) {
+  llvm::DenseMap<llvm::StringRef, llvm::Record *> MacroAttr;
+  for (const auto &Name : Funcs) {
+    if (!Spec.count(Name))
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SchrodingerZhu wrote:

I generally do not think `Spec.count` followed with a `Spec.at` is a good thing. However, this pattern is repeatedly used in some other places and it is not performance critical anyway. 

Tell me if you want me to change this. 

https://github.com/llvm/llvm-project/pull/79891