+external llvm_add_function_attr : llvalue -> int -> unit
+ = "llvm_add_function_attr"
+external llvm_remove_function_attr : llvalue -> int -> unit
+ = "llvm_remove_function_attr"
+
+let pack_attr (attr:Attribute.t) : int =
+ match attr with
+ Attribute.Zext -> 1 lsl 0
+ | Attribute.Sext -> 1 lsl 1
+ | Attribute.Noreturn -> 1 lsl 2
+ | Attribute.Inreg -> 1 lsl 3
+ | Attribute.Structret -> 1 lsl 4
+ | Attribute.Nounwind -> 1 lsl 5
+ | Attribute.Noalias -> 1 lsl 6
+ | Attribute.Byval -> 1 lsl 7
+ | Attribute.Nest -> 1 lsl 8
+ | Attribute.Readnone -> 1 lsl 9
+ | Attribute.Readonly -> 1 lsl 10
+ | Attribute.Noinline -> 1 lsl 11
+ | Attribute.Alwaysinline -> 1 lsl 12
+ | Attribute.Optsize -> 1 lsl 13
+ | Attribute.Ssp -> 1 lsl 14
+ | Attribute.Sspreq -> 1 lsl 15
+ | Attribute.Alignment n -> n lsl 16
+ | Attribute.Nocapture -> 1 lsl 21
+ | Attribute.Noredzone -> 1 lsl 22
+ | Attribute.Noimplicitfloat -> 1 lsl 23
+ | Attribute.Naked -> 1 lsl 24
+ | Attribute.Inlinehint -> 1 lsl 25
+ | Attribute.Stackalignment n -> n lsl 26
+
+let add_function_attr llval attr =
+ llvm_add_function_attr llval (pack_attr attr)
+
+let remove_function_attr llval attr =
+ llvm_remove_function_attr llval (pack_attr attr)