diff --git a/test/misc.cpp b/test/misc.cpp
index dbebf2f..6496f1c 100644
--- a/test/misc.cpp
+++ b/test/misc.cpp
@@ -797,6 +797,10 @@
 		{
 			tileloadd(tmm1, ptr[r8]);
 		}
+		void notSupported2()
+		{
+			tileloadd(tmm1, ptr[r8*2]);
+		}
 	} c;
 	const uint8_t tbl[] = {
 		0xC4, 0x82, 0x7B, 0x4B, 0x0C, 0x00,
@@ -809,5 +813,6 @@
 
 	// current version does not support this sibmem format
 	CYBOZU_TEST_EXCEPTION(c.notSupported(), std::exception);
+	CYBOZU_TEST_EXCEPTION(c.notSupported2(), std::exception);
 }
 #endif
diff --git a/xbyak/xbyak.h b/xbyak/xbyak.h
index 8e31209..b896bd9 100644
--- a/xbyak/xbyak.h
+++ b/xbyak/xbyak.h
@@ -2269,8 +2269,9 @@
 #ifdef XBYAK64
 	void opAMX(const Tmm& t1, const Address& addr, int type, int code0)
 	{
-		// addressing without index such as ptr[r8]
-		if (addr.getRegExp().getIndex().getBit() == 0) throw Error(ERR_NOT_SUPPORTED);
+		// require both base and index
+		const RegExp exp = addr.getRegExp(false);
+		if (exp.getBase().getBit() == 0 || exp.getIndex().getBit() == 0) throw Error(ERR_NOT_SUPPORTED);
 		opVex(t1, &tmm0, addr, type, code0);
 	}
 #endif