[doc] addressing with label
diff --git a/doc/usage.md b/doc/usage.md
index 5e1946a..d08da64 100644
--- a/doc/usage.md
+++ b/doc/usage.md
@@ -354,6 +354,24 @@
mov(eax, ptr[rip + &x]); // throw exception if the difference between &x and current position is larger than 2GiB
```
+### Addressing with Label
+The Label class can be used for addressing displacement.
+However, in 64-bit mode, `dataL.getAddress()` must be 2GiB or less.
+
+```cpp
+Label dataL;
+
+ mov(eax, ptr[dataL+ecx*4]);
+ ...
+L(dataL);
+ for (int i = 0; i < 10; i++) {
+ dd(i);
+ }
+ ...
+```
+
+Only the form `mov((al|ax|eax|rax), ptr[label])` can be used even if the label exceeds 2GiB.
+
## Far jump
Use `word|dword|qword` instead of `ptr` to specify the address size.
