1 files changed, 6 insertions, 2 deletions
diff --git a/library/stdarch/crates/stdarch-test/src/lib.rs b/library/stdarch/crates/stdarch-test/src/lib.rs
index 0275b8d16dc..70797e17c81 100644
--- a/library/stdarch/crates/stdarch-test/src/lib.rs
+++ b/library/stdarch/crates/stdarch-test/src/lib.rs
@@ -76,8 +76,12 @@ pub fn assert(shim_addr: usize, fnname: &str, expected: &str) {
         instrs = &instrs[..instrs.len() - 1];
     }
 
-    // If the expected intrinsic is a nop it is compiled away so we
-    // can't check for it - aka the intrinsic is not generating any code
+    // There are two cases when the expected instruction is nop:
+    // 1. The expected intrinsic is compiled away so we can't
+    // check for it - aka the intrinsic is not generating any code.
+    // 2. It is a mark, indicating that the instruction will be
+    // compiled into other instructions - mainly because of llvm
+    // optimization.
     if expected == "nop" {
         return;
     }