[OCaml] Expose Llvm_executionengine.get_{global_value,function}_address.

Patch by Ramkumar Ramachandra <artagnon@gmail.com>.

Also remove Llvm_executionengine.get_pointer_to_global, as it
is actually deprecated and didn't appear in a stable release.

llvm-svn: 224801

llvm/bindings/ocaml/executionengine/executionengine_ocaml.c

@@ -115,8 +115,12 @@ CAMLprim value llvm_ee_add_global_mapping(LLVMValueRef Global, value Ptr,
   return Val_unit;
 }
 
-/* Llvm.llvalue -> llexecutionengine -> int64 */
-CAMLprim value llvm_ee_get_pointer_to_global(LLVMValueRef Global,
-                                             LLVMExecutionEngineRef EE) {
-  return caml_copy_int64((int64_t) LLVMGetPointerToGlobal(EE, Global));
+CAMLprim value llvm_ee_get_global_value_address(value Name,
+						LLVMExecutionEngineRef EE) {
+  return caml_copy_int64((int64_t) LLVMGetGlobalValueAddress(EE, String_val(Name)));
+}
+
+CAMLprim value llvm_ee_get_function_address(value Name,
+					    LLVMExecutionEngineRef EE) {
+  return caml_copy_int64((int64_t) LLVMGetFunctionAddress(EE, String_val(Name)));
 }

llvm/bindings/ocaml/executionengine/llvm_executionengine.ml

@@ -45,15 +45,27 @@ external data_layout : llexecutionengine -> Llvm_target.DataLayout.t
   = "llvm_ee_get_data_layout"
 external add_global_mapping_ : Llvm.llvalue -> int64 -> llexecutionengine -> unit
   = "llvm_ee_add_global_mapping"
-external get_pointer_to_global_ : Llvm.llvalue -> llexecutionengine -> int64
-  = "llvm_ee_get_pointer_to_global"
+external get_global_value_address_ : string -> llexecutionengine -> int64
+  = "llvm_ee_get_global_value_address"
+external get_function_address_ : string -> llexecutionengine -> int64
+  = "llvm_ee_get_function_address"
 
 let add_global_mapping llval ptr ee =
   add_global_mapping_ llval (Ctypes.raw_address_of_ptr (Ctypes.to_voidp ptr)) ee
 
-let get_pointer_to_global llval typ ee =
-  Ctypes.coerce (let open Ctypes in ptr void) typ
-                (Ctypes.ptr_of_raw_address (get_pointer_to_global_ llval ee))
+let get_global_value_address name typ ee =
+  let vptr = get_global_value_address_ name ee in
+  if Int64.to_int vptr <> 0 then
+    let open Ctypes in !@ (coerce (ptr void) (ptr typ) (ptr_of_raw_address vptr))
+  else
+    raise (Error ("Value " ^ name ^ " not found"))
+
+let get_function_address name typ ee =
+  let fptr = get_function_address_ name ee in
+  if Int64.to_int fptr <> 0 then
+    let open Ctypes in coerce (ptr void) typ (ptr_of_raw_address fptr)
+  else
+    raise (Error ("Function " ^ name ^ " not found"))
 
 (* The following are not bound. Patches are welcome.
 target_machine : llexecutionengine -> Llvm_target.TargetMachine.t

llvm/bindings/ocaml/executionengine/llvm_executionengine.mli

@@ -76,9 +76,18 @@ val data_layout : llexecutionengine -> Llvm_target.DataLayout.t
     All uses of [gv] in the compiled code will refer to [ptr]. *)
 val add_global_mapping : Llvm.llvalue -> 'a Ctypes.ptr -> llexecutionengine -> unit
 
-(** [get_pointer_to_global gv typ ee] returns the value of the global
-    variable [gv] in the execution engine [ee] as type [typ], which may
-    be a pointer type (e.g. [int ptr typ]) for global variables or
-    a function (e.g. [(int -> int) typ]) type for functions, and which
-    will be live as long as [gv] and [ee] are. *)
-val get_pointer_to_global : Llvm.llvalue -> 'a Ctypes.typ -> llexecutionengine -> 'a
+(** [get_global_value_address id typ ee] returns a pointer to the
+    identifier [id] as type [typ], which will be a pointer type for a
+    value, and which will be live as long as [id] and [ee]
+    are. Caution: this function finalizes, i.e. forces code
+    generation, all loaded modules.  Further modifications to the
+    modules will not have any effect. *)
+val get_global_value_address : string -> 'a Ctypes.typ -> llexecutionengine -> 'a
+
+(** [get_function_address fn typ ee] returns a pointer to the function
+    [fn] as type [typ], which will be a pointer type for a function
+    (e.g. [(int -> int) typ]), and which will be live as long as [fn]
+    and [ee] are. Caution: this function finalizes, i.e. forces code
+    generation, all loaded modules.  Further modifications to the
+    modules will not have any effect. *)
+val get_function_address : string -> 'a Ctypes.typ -> llexecutionengine -> 'a

llvm/test/Bindings/OCaml/executionengine.ml

@@ -50,7 +50,10 @@ let test_executionengine () =
   let ee = create m in
 
   (* add plus *)
-  let plus = define_plus m in
+  ignore (define_plus m);
+
+  (* declare global variable *)
+  ignore (define_global "globvar" (const_int i32_type 23) m);
 
   (* add module *)
   let m2 = create_module (global_context ()) "test_module2" in
@@ -73,9 +76,13 @@ let test_executionengine () =
   (* run_static_ctors *)
   run_static_ctors ee;
 
+  (* get a handle on globvar *)
+  let varh    = get_global_value_address "globvar" int32_t ee in
+  if 23l <> varh then bomb "get_global_value_address didn't work";
+
   (* call plus *)
   let cplusty = Foreign.funptr (int32_t @-> int32_t @-> returning int32_t) in
-  let cplus   = get_pointer_to_global plus cplusty ee in
+  let cplus   = get_function_address "plus" cplusty ee in
   if 4l <> cplus 2l 2l then bomb "plus didn't work";
 
   (* call getglobal *)