SymbolID rewrite

Author: sdkrystian

include/mrdox/Metadata/Record.hpp

@@ -51,7 +51,7 @@ struct BaseInfo
     bool IsVirtual;
 
     BaseInfo(
-        SymbolID const& id_ = EmptySID,
+        SymbolID const& id_ = SymbolID::zero,
         std::string_view Name_ = "",
         Access access_ = Access::Public,
         bool IsVirtual_ = false)

include/mrdox/Metadata/Reference.hpp

@@ -44,7 +44,7 @@ struct Reference
     // string as a valid input for the global namespace (it will have
     // "GlobalNamespace" as the name, but an empty QualName).
     Reference(
-        SymbolID id_ = EmptySID,
+        SymbolID id_ = SymbolID::zero,
         llvm::StringRef Name = llvm::StringRef(),
         InfoType IT = InfoType::IT_default)
         : id(id_)

include/mrdox/Metadata/Symbols.hpp

@@ -5,6 +5,7 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 // Copyright (c) 2023 Vinnie Falco ([email protected])
+// Copyright (c) 2023 Krystian Stasiowski ([email protected])
 //
 // Official repository: https://github.com/cppalliance/mrdox
 //
@@ -14,7 +15,9 @@
 
 #include <mrdox/Platform.hpp>
 #include <llvm/ADT/StringRef.h>
-#include <array>
+#include <cstdint>
+#include <cstring>
+#include <compare>
 
 namespace clang {
 namespace mrdox {
@@ -25,22 +28,72 @@ namespace mrdox {
     USR. A USRs is a string that provide an
     unambiguous reference to a symbol.
 */
-struct SymbolID :
-    std::array<std::uint8_t, 20>
+class SymbolID
 {
+public:
+    static const SymbolID zero;
+
+    using value_type = std::uint8_t;
+
     constexpr SymbolID() = default;
-    constexpr SymbolID(const std::array<std::uint8_t, 20>& arr)
-        : array(arr)
+
+    template<typename Elem>
+    SymbolID(const Elem* src)
+    {
+        for(auto& c : data_)
+            c = *src++;
+    }
+
+    constexpr auto data() const noexcept
+    {
+        return data_;
+    }
+
+    constexpr std::size_t size() const noexcept
+    {
+        return 20;
+    }
+
+    constexpr auto begin() const noexcept
     {
+        return data_;
     }
+
+    constexpr auto end() const noexcept
+    {
+        return data_ + size();
+    }
+
+    operator llvm::StringRef() const noexcept
+    {
+        return llvm::StringRef(reinterpret_cast<
+            const char*>(data()), size());
+    }
+
+    auto operator<=>(
+        const SymbolID& other) const noexcept
+    {
+        return std::memcmp(
+            data(),
+            other.data(),
+            size()) <=> 0;
+    }
+
+    bool operator==(
+        const SymbolID& other) const noexcept = default;
+
+private:
+    value_type data_[20];
 };
 
 /** The empty Symbol ID.
 
     This is used to avoid unnecessary constructions,
     and to identify the global namespace.
 */
-constexpr SymbolID const EmptySID = SymbolID();
+// KRYSTIAN NOTE: msvc requires inline as it doesn't consider SymbolID::zero
+// to be an inline variable without it (it should; see [dcl.constexpr])
+constexpr inline SymbolID SymbolID::zero = SymbolID();
 
 /** Like optional<SymbolID>
 */
@@ -86,7 +139,7 @@ class OptionalSymbolID
 
     constexpr bool has_value() const noexcept
     {
-        return ID_ != EmptySID;
+        return ID_ != SymbolID::zero;
     }
 
     template<typename... Args>
@@ -97,10 +150,6 @@ class OptionalSymbolID
     }
 };
 
-/** The ID of the global namespace.
-*/
-constexpr SymbolID const globalNamespaceID = EmptySID;
-
 /** Info variant discriminator
 */
 enum class InfoType

include/mrdox/Metadata/Type.hpp

@@ -58,7 +58,7 @@ struct TypeInfo
     TypeInfo(
         llvm::StringRef Name)
         : Type(
-            EmptySID, Name, InfoType::IT_default)
+            SymbolID::zero, Name, InfoType::IT_default)
     {
     }
 

source/-XML/XMLTags.hpp

@@ -101,7 +101,7 @@ struct Attribute
         SymbolID id)
         : name("id")
         , value(toString(id))
-        , pred(id != EmptySID)
+        , pred(id != SymbolID::zero)
     {
     }
 

source/-XML/XMLWriter.cpp

@@ -149,7 +149,7 @@ build()
     if(options_.index || options_.safe_names)
         writeIndex();
 
-    if(! corpus_.traverse(*this, globalNamespaceID))
+    if(! corpus_.traverse(*this, SymbolID::zero))
         return makeErr("visit failed");
 
     if(options_.prolog)
@@ -555,7 +555,7 @@ writeTemplate(
         break;
     }
     const SymbolID& id = I->Primary ?
-        *I->Primary : EmptySID;
+        *I->Primary : SymbolID::zero;
 
     tags_.open(templateTagName, {
         {"class", spec, !! spec},

source/-adoc/AdocPagesBuilder.cpp

@@ -24,7 +24,7 @@ Err
 AdocPagesBuilder::
 build()
 {
-    corpus_.traverse(*this, globalNamespaceID);
+    corpus_.traverse(*this, SymbolID::zero);
     wg_.wait();
     return {};
 }

source/-adoc/AdocSinglePageWriter.cpp

@@ -38,7 +38,7 @@ build()
     os_ <<
         "= Reference\n"
         ":role: mrdox\n";
-    corpus_.traverse(*this, globalNamespaceID);
+    corpus_.traverse(*this, SymbolID::zero);
     endSection();
     return {};
 }
@@ -93,7 +93,7 @@ visit(
         ! I.Children.Vars.empty())
     {
         std::string s;
-        if(I.id == EmptySID)
+        if(I.id == SymbolID::zero)
         {
             s = "global namespace";
         }

source/-adoc/AdocWriter.cpp

@@ -134,7 +134,7 @@ struct AdocWriter::TypeName
         llvm::raw_ostream& os,
         TypeName const& t)
     {
-        if(t.I.Type.id == globalNamespaceID)
+        if(t.I.Type.id == SymbolID::zero)
         {
             os << t.I.Type.Name;
             return os;

source/-bitcode/BitcodeGenerator.cpp

@@ -43,7 +43,7 @@ class MultiFileBuilder : public Corpus::Visitor
     Err
     build()
     {
-        corpus_.traverse(*this, globalNamespaceID);
+        corpus_.traverse(*this, SymbolID::zero);
         wg_.wait();
         return Err();
     }
@@ -128,7 +128,7 @@ class SingleFileBuilder : public Corpus::Visitor
     Err
     build()
     {
-        corpus_.traverse(*this, globalNamespaceID);
+        corpus_.traverse(*this, SymbolID::zero);
         return Err();
     }