diff --git a/asm.js b/asm.js
index 3668b19..2c277fb 100644
--- a/asm.js
+++ b/asm.js
@@ -167,6 +167,14 @@ const opcodes = {
     "i32.shl":       0x74,
     "i32.shr_s":     0x75,
     "i32.shr_u":     0x76,
+
+    // Threads instructions
+    "memory.atomic.notify":  [ 0xfe, 0x00 ],
+    "memory.atomic.wait32":  [ 0xfe, 0x01 ],
+    "memory.atomic.load":    [ 0xfe, 0x10 ],
+    "memory.atomic.load8_u": [ 0xfe, 0x12 ],
+    "memory.atomic.store":   [ 0xfe, 0x17 ],
+    "memory.atomic.store8":  [ 0xfe, 0x19 ],
 };
 
 const mem_flags = {