update document
diff --git a/readme.md b/readme.md
index ac7e110..37a95c9 100644
--- a/readme.md
+++ b/readme.md
@@ -139,6 +139,7 @@
vaddpd(zmm2 | k5 | T_z | T_rd_sae, zmm4, zmm2); // the position of `|` is arbitrary.
vcmppd k4{k3}, zmm1, zmm2, {sae}, 5 --> vcmppd(k4 | k3, zmm1, zmm2 | T_sae, 5);
+vaddpd xmm1, xmm2, [rax+256] --> vaddpd(xmm1, xmm2, ptr [rax+256]);
vaddpd xmm1, xmm2, [rax+256]{1to2} --> vaddpd(xmm1, xmm2, ptr_b [rax+256]);
vaddpd ymm1, ymm2, [rax+256]{1to4} --> vaddpd(ymm1, ymm2, ptr_b [rax+256]);
vaddpd zmm1, zmm2, [rax+256]{1to8} --> vaddpd(zmm1, zmm2, ptr_b [rax+256]);
@@ -159,7 +160,7 @@
* use `| T_z`, `| T_sae`, `| T_rn_sae`, `| T_rd_sae`, `| T_ru_sae`, `| T_rz_sae` instead of `,{z}`, `,{sae}`, `,{rn-sae}`, `,{rd-sae}`, `,{ru-sae}`, `,{rz-sae}` respectively.
* `k4 | k3` is different from `k3 | k4`.
* use `ptr_b` for broadcast `{1toX}`. X is automatically determined.
-* specify xword/yword/zword(_b) for m128/m256/m512.
+* specify xword/yword/zword(_b) for m128/m256/m512 if necessary.
### Label
