RJIT: Distinguish Pointer with Array

This is more convenient for accessing those fields.

2 files changed, 42 insertions, 0 deletions

diff --git a/lib/ruby_vm/rjit/c_pointer.rb b/lib/ruby_vm/rjit/c_pointer.rb
index 1a84896822..db00c4cd11 100644
--- a/lib/ruby_vm/rjit/c_pointer.rb
+++ b/lib/ruby_vm/rjit/c_pointer.rb
@@ -238,6 +238,40 @@ module RubyVM::RJIT
       end
     end
 
+    # Basically Immediate but without #* to skip auto-dereference of structs.
+    class Array
+      attr_reader :type
+
+      # @param addr [Integer]
+      # @param type [Class] RubyVM::RJIT::CType::*
+      def initialize(addr, type)
+        @addr = addr
+        @type = type
+      end
+
+      # Array access
+      def [](index)
+        @type.new(@addr)[index]
+      end
+
+      # Array set
+      # @param index [Integer]
+      # @param value [Integer, RubyVM::RJIT::CPointer::Struct] an address itself or an object that return an address with to_i
+      def []=(index, value)
+        @type.new(@addr)[index] = value
+      end
+
+      private
+
+      def self.define(block)
+        Class.new(self) do
+          define_method(:initialize) do |addr|
+            super(addr, block.call)
+          end
+        end
+      end
+    end
+
     class Pointer
       attr_reader :type
 
diff --git a/lib/ruby_vm/rjit/c_type.rb b/lib/ruby_vm/rjit/c_type.rb
index bec7e21c38..3b313a658b 100644
--- a/lib/ruby_vm/rjit/c_type.rb
+++ b/lib/ruby_vm/rjit/c_type.rb
@@ -62,6 +62,14 @@ module RubyVM::RJIT
       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]