diff --git a/nemu/src/isa/riscv32/inst.c b/nemu/src/isa/riscv32/inst.c
index 1e7b9ee..1208cb4 100644
--- a/nemu/src/isa/riscv32/inst.c
+++ b/nemu/src/isa/riscv32/inst.c
@@ -135,14 +135,14 @@ static int decode_exec(Decode *s) {
   INSTPAT("??????? ????? ????? ??? ????? ????? ??", inv    , N, INV(s->pc));
 
   // "M"
-  INSTPAT("0000001 ????? ????? 000 ????? 01100 11", mul, R, R(rd) = src1 * src2);
-  INSTPAT("0000001 ????? ????? 001 ????? 01100 11", mulh, R, R(rd) = (uint64_t)src1 * (uint64_t)src2 >> 32);
-  INSTPAT("0000001 ????? ????? 010 ????? 01100 11", mulhsu, R, R(rd) = (int64_t)src1 * (uint64_t)src2 >> 32);
-  INSTPAT("0000001 ????? ????? 011 ????? 01100 11", mulhu, R, R(rd) = (int64_t)src1 * (int64_t)src2 >> 32);
-  INSTPAT("0000001 ????? ????? 100 ????? 01100 11", div, R, R(rd) = (sword_t)src1 / (sword_t)src2);
-  INSTPAT("0000001 ????? ????? 101 ????? 01100 11", divu, R, R(rd) = src1 / src2);
-  INSTPAT("0000001 ????? ????? 110 ????? 01100 11", rem, R, R(rd) = (sword_t)src1 % (sword_t)src2);
-  INSTPAT("0000001 ????? ????? 111 ????? 01100 11", remu, R, R(rd) = src1 % src2);
+  // INSTPAT("0000001 ????? ????? 000 ????? 01100 11", mul, R, R(rd) = src1 * src2);
+  // INSTPAT("0000001 ????? ????? 001 ????? 01100 11", mulh, R, R(rd) = (uint64_t)src1 * (uint64_t)src2 >> 32);
+  // INSTPAT("0000001 ????? ????? 010 ????? 01100 11", mulhsu, R, R(rd) = (int64_t)src1 * (uint64_t)src2 >> 32);
+  // INSTPAT("0000001 ????? ????? 011 ????? 01100 11", mulhu, R, R(rd) = (int64_t)src1 * (int64_t)src2 >> 32);
+  // INSTPAT("0000001 ????? ????? 100 ????? 01100 11", div, R, R(rd) = (sword_t)src1 / (sword_t)src2);
+  // INSTPAT("0000001 ????? ????? 101 ????? 01100 11", divu, R, R(rd) = src1 / src2);
+  // INSTPAT("0000001 ????? ????? 110 ????? 01100 11", rem, R, R(rd) = (sword_t)src1 % (sword_t)src2);
+  // INSTPAT("0000001 ????? ????? 111 ????? 01100 11", remu, R, R(rd) = src1 % src2);
 
   INSTPAT_END();