added hpx::merge

Signed-off-by: Dikshant <[email protected]>

hpx-sys/include/wrapper.h

@@ -161,3 +161,22 @@ inline void hpx_sort_comp(rust::Vec<int32_t>& src, rust::Fn<bool(int32_t, int32_
         src.push_back(item);
     }
 }
+
+inline void hpx_merge(const rust::Vec<int32_t>& src1, 
+                               const rust::Vec<int32_t>& src2, 
+                               rust::Vec<int32_t>& dest) {
+    std::vector<int32_t> cpp_src1(src1.begin(), src1.end());
+    std::vector<int32_t> cpp_src2(src2.begin(), src2.end());
+    std::vector<int32_t> cpp_dest(cpp_src1.size() + cpp_src2.size());
+
+    hpx::merge(hpx::execution::par,
+               cpp_src1.begin(), cpp_src1.end(),
+               cpp_src2.begin(), cpp_src2.end(),
+               cpp_dest.begin());
+
+    dest.clear();
+    dest.reserve(cpp_dest.size());
+    for (const auto& item : cpp_dest) {
+        dest.push_back(item);
+    }
+}

hpx-sys/src/lib.rs

@@ -29,6 +29,7 @@ pub mod ffi {
         fn hpx_find(src: &Vec<i32>, value: i32) -> i64;
         fn hpx_sort(src: &mut Vec<i32>);
         fn hpx_sort_comp(src: &mut Vec<i32>, comp: fn(i32, i32) -> bool);
+        fn hpx_merge(src1: &Vec<i32>, src2: &Vec<i32>, dest: &mut Vec<i32>);
     }
 }
 
@@ -400,4 +401,24 @@ mod tests {
             assert_eq!(result, 0);
         }
     }
+
+    #[test]
+    #[serial]
+    fn test_hpx_merge() {
+        let (argc, mut argv) = create_c_args(&["test_hpx_merge"]);
+
+        let hpx_main = |_argc: i32, _argv: *mut *mut c_char| -> i32 {
+            let v1 = vec![1, 3, 5, 7, 9, 20, 100];
+            let v2 = vec![2, 4, 6, 8, 10, 97];
+            let mut dest = Vec::new();
+            ffi::hpx_merge(&v1, &v2, &mut dest);
+            assert_eq!(dest, vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 97, 100]);
+            ffi::finalize()
+        };
+
+        unsafe {
+            let result = ffi::init(hpx_main, argc, argv.as_mut_ptr());
+            assert_eq!(result, 0);
+        }
+    }
 }