[Metal] Emit global dynamic memory

Author: christiangnrd

src/metal.jl

@@ -168,6 +168,8 @@ function finish_ir!(@nospecialize(job::CompilerJob{MetalCompilerTarget}), mod::L
 
         add_argument_metadata!(job, mod, entry)
 
+        add_globals_metadata!(job, mod, entry)
+
         add_module_metadata!(job, mod)
     end
 
@@ -550,6 +552,96 @@ function argument_type_name(typ)
     end
 end
 
+# global metadata generation
+#
+# module metadata is used to identify global buffers that are used as kernel arguments.
+function add_globals_metadata!(@nospecialize(job::CompilerJob), mod::LLVM.Module,
+                                entry::LLVM.Function)
+    entry_ft = function_type(entry)
+
+    ## argument info
+    arg_infos = Metadata[]
+
+
+    # Iterate through arguments and create metadata for them
+    globs = globals(mod)
+    @show globs
+    i = 1
+    for gv in globs
+        @show gv
+        gv_typ = global_value_type(gv)
+        (isconstant(gv) && addrspace(gv_typ) == 3) || continue
+        # if job.config.optimize
+        #     @assert parameters(entry_ft)[arg.idx] isa LLVM.PointerType
+        # else
+        #     parameters(entry_ft)[arg.idx] isa LLVM.PointerType || continue
+        # end
+
+        # # NOTE: we emit the bare minimum of argument metadata to support
+        # #       bindless argument encoding. Actually using the argument encoder
+        # #       APIs (deprecated in Metal 3) turned out too difficult, given the
+        # #       undocumented nature of the argument metadata, and the complex
+        # #       arguments we encounter with typical Julia kernels.
+        global_infos = Metadata[]
+
+        push!(global_infos, MDString("air.global_binding"))
+        push!(global_infos, Metadata(gv))
+
+        md = Metadata[]
+
+        # argument index
+        push!(md, Metadata(ConstantInt(Int32(-1))))
+
+        push!(md, MDString("air.buffer"))
+
+        push!(md, MDString("air.location_index"))
+        push!(md, Metadata(ConstantInt(Int32(i-1))))
+
+        # XXX: unknown
+        push!(md, Metadata(ConstantInt(Int32(1))))
+
+        push!(md, MDString("air.read_write")) # TODO: Check for const array
+
+        push!(md, MDString("air.address_space"))
+        push!(md, Metadata(ConstantInt(Int32(addrspace(global_value_type(gv))))))
+
+        val_type = global_value_type(gv)
+        # val_type = if value_type(gv) <: Core.LLVMPtr
+        #     arg.typ.parameters[1]
+        # else
+        #     arg.typ
+        # end
+
+        @show gv_typ
+        @show isconstant(gv)
+        # @show isconstant(gv_typ)
+        # @show Int32(alignment(gv))
+
+        push!(md, MDString("air.arg_type_size"))
+        push!(md, Metadata(ConstantInt(Int32(4))))
+
+        push!(md, MDString("air.arg_type_align_size"))
+        push!(md, Metadata(ConstantInt(Int32(alignment(gv)))))
+
+        push!(md, MDString("air.arg_type_name"))
+        # push!(md, MDString(repr(arg.typ)))
+
+        push!(md, MDString("air.arg_name"))
+        push!(md, MDString(String(LLVM.name(gv))))
+
+        push!(arg_infos, MDNode(md))
+
+        i += 1
+    end
+
+    println()
+    arg_infos = MDNode(arg_infos)
+
+    push!(metadata(mod)["air.global_bindings"], arg_infos)
+
+    return
+end
+
 # argument metadata generation
 #
 # module metadata is used to identify buffers that are passed as kernel arguments.