From 0980da373ce5601e24abb5a0a618ea3d3c6eeedc Mon Sep 17 00:00:00 2001
From: Peter Zotov <whitequark@whitequark.org>
Date: Sun, 3 Aug 2014 23:54:22 +0000
Subject: [PATCH] [OCaml] Add Llvm.{string_of_const,const_element}.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214677 91177308-0d34-0410-b5e6-96231b3b80d8
---
 bindings/ocaml/llvm/llvm.ml      |  2 ++
 bindings/ocaml/llvm/llvm.mli     |  9 ++++++++-
 bindings/ocaml/llvm/llvm_ocaml.c | 25 +++++++++++++++++++++++++
 test/Bindings/Ocaml/vmcore.ml    |  6 +++++-
 4 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/bindings/ocaml/llvm/llvm.ml b/bindings/ocaml/llvm/llvm.ml
index 39875a5ed48..a52bf004e59 100644
--- a/bindings/ocaml/llvm/llvm.ml
+++ b/bindings/ocaml/llvm/llvm.ml
@@ -479,6 +479,8 @@ external const_named_struct : lltype -> llvalue array -> llvalue
 external const_packed_struct : llcontext -> llvalue array -> llvalue
                              = "llvm_const_packed_struct"
 external const_vector : llvalue array -> llvalue = "llvm_const_vector"
+external string_of_const : llvalue -> string option = "llvm_string_of_const"
+external const_element : llvalue -> int -> llvalue = "llvm_const_element"
 
 (*--... Constant expressions ...............................................--*)
 external align_of : lltype -> llvalue = "LLVMAlignOf"
diff --git a/bindings/ocaml/llvm/llvm.mli b/bindings/ocaml/llvm/llvm.mli
index f5f5b53e84d..adb87ef1170 100644
--- a/bindings/ocaml/llvm/llvm.mli
+++ b/bindings/ocaml/llvm/llvm.mli
@@ -841,7 +841,6 @@ val const_float : lltype -> float -> llvalue
     [ty] and value [n]. See the method [llvm::ConstantFP::get]. *)
 val const_float_of_string : lltype -> string -> llvalue
 
-
 (** {7 Operations on composite constants} *)
 
 (** [const_string c s] returns the constant [i8] array with the values of the
@@ -887,6 +886,14 @@ val const_packed_struct : llcontext -> llvalue array -> llvalue
     values [elts]. See the method [llvm::ConstantVector::get]. *)
 val const_vector : llvalue array -> llvalue
 
+(** [string_of_const c] returns [Some str] if [c] is a string constant,
+    or [None] if this is not a string constant. *)
+val string_of_const : llvalue -> string option
+
+(** [const_element c] returns a constant for a specified index's element.
+    See the method ConstantDataSequential::getElementAsConstant. *)
+val const_element : llvalue -> int -> llvalue
+
 
 (** {7 Constant expressions} *)
 
diff --git a/bindings/ocaml/llvm/llvm_ocaml.c b/bindings/ocaml/llvm/llvm_ocaml.c
index 2044856ef2d..3ec76835696 100644
--- a/bindings/ocaml/llvm/llvm_ocaml.c
+++ b/bindings/ocaml/llvm/llvm_ocaml.c
@@ -782,6 +782,31 @@ CAMLprim LLVMValueRef llvm_const_vector(value ElementVals) {
                          Wosize_val(ElementVals));
 }
 
+/* llvalue -> string option */
+CAMLprim value llvm_string_of_const(LLVMValueRef Const) {
+  const char *S;
+  size_t Len;
+  CAMLparam0();
+  CAMLlocal2(Option, Str);
+
+  if(LLVMIsAConstantDataSequential(Const) && LLVMIsConstantString(Const)) {
+    S = LLVMGetAsString(Const, &Len);
+    Str = caml_alloc_string(Len);
+    memcpy(String_val(Str), S, Len);
+
+    Option = alloc(1, 0);
+    Field(Option, 0) = Str;
+    CAMLreturn(Option);
+  } else {
+    CAMLreturn(Val_int(0));
+  }
+}
+
+/* llvalue -> int -> llvalue */
+CAMLprim LLVMValueRef llvm_const_element(LLVMValueRef Const, value N) {
+  return LLVMGetElementAsConstant(Const, Int_val(N));
+}
+
 /*--... Constant expressions ...............................................--*/
 
 /* Icmp.t -> llvalue -> llvalue -> llvalue */
diff --git a/test/Bindings/Ocaml/vmcore.ml b/test/Bindings/Ocaml/vmcore.ml
index 53e0553b0d5..ea9129497f3 100644
--- a/test/Bindings/Ocaml/vmcore.ml
+++ b/test/Bindings/Ocaml/vmcore.ml
@@ -125,6 +125,7 @@ let test_constants () =
   let c = const_int_of_string i32_type "-1" 10 in
   ignore (define_global "const_int_string" c m);
   insist (i32_type = type_of c);
+  insist (None = (string_of_const c));
 
   if Sys.word_size = 64; then begin
     group "long int";
@@ -138,6 +139,7 @@ let test_constants () =
   let c = const_string context "cruel\000world" in
   ignore (define_global "const_string" c m);
   insist ((array_type i8_type 11) = type_of c);
+  insist ((Some "cruel\000world") = (string_of_const c));
 
   (* CHECK: const_stringz{{.*}}"hi\00again\00"
    *)
@@ -175,7 +177,9 @@ let test_constants () =
   let c = const_array i32_type [| three; four |] in
   ignore (define_global "const_array" c m);
   insist ((array_type i32_type 2) = (type_of c));
-  
+  insist (three = (const_element c 0));
+  insist (four = (const_element c 1));
+
   (* CHECK: const_vector{{.*}}<i16 1, i16 2{{.*}}>
    *)
   group "vector";
-- 
2.34.1