diff --git a/lib/syntax_tree/yarv/assembler.rb b/lib/syntax_tree/yarv/assembler.rb
index ac400506..b29c252a 100644
--- a/lib/syntax_tree/yarv/assembler.rb
+++ b/lib/syntax_tree/yarv/assembler.rb
@@ -31,7 +31,6 @@ def visit_string_literal(node)
         "FCALL" => CallData::CALL_FCALL,
         "VCALL" => CallData::CALL_VCALL,
         "ARGS_SIMPLE" => CallData::CALL_ARGS_SIMPLE,
-        "BLOCKISEQ" => CallData::CALL_BLOCKISEQ,
         "KWARG" => CallData::CALL_KWARG,
         "KW_SPLAT" => CallData::CALL_KW_SPLAT,
         "TAILCALL" => CallData::CALL_TAILCALL,
diff --git a/lib/syntax_tree/yarv/calldata.rb b/lib/syntax_tree/yarv/calldata.rb
index fadea61b..e35992f5 100644
--- a/lib/syntax_tree/yarv/calldata.rb
+++ b/lib/syntax_tree/yarv/calldata.rb
@@ -5,19 +5,26 @@ module YARV
     # This is an operand to various YARV instructions that represents the
     # information about a specific call site.
     class CallData
-      CALL_ARGS_SPLAT = 1 << 0
-      CALL_ARGS_BLOCKARG = 1 << 1
-      CALL_FCALL = 1 << 2
-      CALL_VCALL = 1 << 3
-      CALL_ARGS_SIMPLE = 1 << 4
-      CALL_BLOCKISEQ = 1 << 5
-      CALL_KWARG = 1 << 6
-      CALL_KW_SPLAT = 1 << 7
-      CALL_TAILCALL = 1 << 8
-      CALL_SUPER = 1 << 9
-      CALL_ZSUPER = 1 << 10
-      CALL_OPT_SEND = 1 << 11
-      CALL_KW_SPLAT_MUT = 1 << 12
+      flags = %i[
+        CALL_ARGS_SPLAT
+        CALL_ARGS_BLOCKARG
+        CALL_FCALL
+        CALL_VCALL
+        CALL_ARGS_SIMPLE
+        CALL_KWARG
+        CALL_KW_SPLAT
+        CALL_TAILCALL
+        CALL_SUPER
+        CALL_ZSUPER
+        CALL_OPT_SEND
+        CALL_KW_SPLAT_MUT
+      ]
+
+      # Insert the legacy CALL_BLOCKISEQ flag for Ruby 3.2 and earlier.
+      flags.insert(5, :CALL_BLOCKISEQ) if RUBY_VERSION < "3.3"
+
+      # Set the flags as constants on the class.
+      flags.each_with_index { |name, index| const_set(name, 1 << index) }
 
       attr_reader :method, :argc, :flags, :kw_arg
 
@@ -50,7 +57,6 @@ def inspect
         names << :FCALL if flag?(CALL_FCALL)
         names << :VCALL if flag?(CALL_VCALL)
         names << :ARGS_SIMPLE if flag?(CALL_ARGS_SIMPLE)
-        names << :BLOCKISEQ if flag?(CALL_BLOCKISEQ)
         names << :KWARG if flag?(CALL_KWARG)
         names << :KW_SPLAT if flag?(CALL_KW_SPLAT)
         names << :TAILCALL if flag?(CALL_TAILCALL)