1 files changed, 99 insertions, 0 deletions
diff --git a/lib/ruby_vm/rjit/c_type.rb b/lib/ruby_vm/rjit/c_type.rb
new file mode 100644
index 0000000000..3b313a658b
--- /dev/null
+++ b/lib/ruby_vm/rjit/c_type.rb
@@ -0,0 +1,99 @@
+require 'fiddle'
+require 'fiddle/pack'
+require_relative 'c_pointer'
+
+module RubyVM::RJIT
+  module CType
+    module Struct
+      # @param name [String]
+      # @param members [Hash{ Symbol => [Integer, RubyVM::RJIT::CType::*] }]
+      def self.new(name, sizeof, **members)
+        name = members.keys.join('_') if name.empty?
+        CPointer.with_class_name('Struct', name) do
+          CPointer::Struct.define(sizeof, members)
+        end
+      end
+    end
+
+    module Union
+      # @param name [String]
+      # @param members [Hash{ Symbol => RubyVM::RJIT::CType::* }]
+      def self.new(name, sizeof, **members)
+        name = members.keys.join('_') if name.empty?
+        CPointer.with_class_name('Union', name) do
+          CPointer::Union.define(sizeof, members)
+        end
+      end
+    end
+
+    module Immediate
+      # @param fiddle_type [Integer]
+      def self.new(fiddle_type)
+        name = Fiddle.constants.find do |const|
+          const.start_with?('TYPE_') && Fiddle.const_get(const) == fiddle_type.abs
+        end&.to_s
+        name.delete_prefix!('TYPE_')
+        if fiddle_type.negative?
+          name.prepend('U')
+        end
+        CPointer.with_class_name('Immediate', name, cache: true) do
+          CPointer::Immediate.define(fiddle_type)
+        end
+      end
+
+      # @param type [String]
+      def self.parse(ctype)
+        new(Fiddle::Importer.parse_ctype(ctype))
+      end
+
+      def self.find(size, signed)
+        fiddle_type = TYPE_MAP.fetch(size)
+        fiddle_type = -fiddle_type unless signed
+        new(fiddle_type)
+      end
+
+      TYPE_MAP = Fiddle::PackInfo::SIZE_MAP.map { |type, size| [size, type.abs] }.to_h
+      private_constant :TYPE_MAP
+    end
+
+    module Bool
+      def self.new
+        CPointer::Bool
+      end
+    end
+
+    class Array
+      def self.new(&block)
+        CPointer.with_class_name('Array', block.object_id.to_s) do
+          CPointer::Array.define(block)
+        end
+      end
+    end
+
+    class Pointer
+      # This takes a block to avoid "stack level too deep" on a cyclic reference
+      # @param block [Proc]
+      def self.new(&block)
+        CPointer.with_class_name('Pointer', block.object_id.to_s) do
+          CPointer::Pointer.define(block)
+        end
+      end
+    end
+
+    module BitField
+      # @param width [Integer]
+      # @param offset [Integer]
+      def self.new(width, offset)
+        CPointer.with_class_name('BitField', "#{offset}_#{width}") do
+          CPointer::BitField.define(width, offset)
+        end
+      end
+    end
+
+    # Types that are referenced but not part of code generation targets
+    Stub = ::Struct.new(:name)
+
+    # Types that it failed to figure out from the header
+    Unknown = Module.new
+  end
+end