diff --git a/Project.toml b/Project.toml
index f5d149d82..9f7141743 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,6 +1,6 @@
 name = "GPUCompiler"
 uuid = "61eb1bfa-7361-4325-ad38-22787b887f55"
-version = "1.22.1"
+version = "1.22.2"
 authors = ["Tim Besard <tim.besard@gmail.com>"]
 
 [workspace]
diff --git a/src/metal.jl b/src/metal.jl
index 5107b02ab..dc6f32ed3 100644
--- a/src/metal.jl
+++ b/src/metal.jl
@@ -1270,7 +1270,13 @@ function add_argument_metadata!(@nospecialize(job::CompilerJob), mod::LLVM.Modul
         # XXX: unknown
         push!(md, Metadata(ConstantInt(Int32(1))))
 
-        push!(md, MDString("air.read_write")) # TODO: Check for const array
+        # only pointer-to-data arguments are written through; by-reference values (kernel
+        # state, bitstype objects) are read into a stack slot and never written back.
+        if arg.cc == BITS_VALUE && (arg.typ <: Ptr || arg.typ <: Core.LLVMPtr)
+            push!(md, MDString("air.read_write"))
+        else
+            push!(md, MDString("air.read"))
+        end
 
         push!(md, MDString("air.address_space"))
         push!(md, Metadata(ConstantInt(Int32(addrspace(parameters(entry_ft)[arg.idx])))))