(*===-- Instruction builders ----------------------------------------------===*)
+external builder: unit-> llbuilder
+ = "llvm_builder"
external builder_before : llvalue -> llbuilder = "llvm_builder_before"
external builder_at_end : llbasicblock -> llbuilder = "llvm_builder_at_end"
external position_before : llvalue -> llbuilder -> unit = "llvm_position_before"