Add codegen test for intinsics::ptr_mask

Author: WaffleLapkin

src/test/codegen/intrinsics/mask.rs

@@ -0,0 +1,7 @@
+#![crate_type = "lib"]
+#![feature(core_intrinsics)]
+
+pub fn mask_ptr(ptr: *const u8, mask: usize) -> *const u8 {
+    // CHECK: llvm.ptrmask
+    core::intrinsics::ptr_mask(ptr, mask)
+}