diff --git a/nemu/src/isa/riscv32/inst.c b/nemu/src/isa/riscv32/inst.c
index 1208cb4..c8d18d1 100644
--- a/nemu/src/isa/riscv32/inst.c
+++ b/nemu/src/isa/riscv32/inst.c
@@ -89,28 +89,14 @@ static int decode_exec(Decode *s) {
   INSTPAT("??????? ????? ????? ??? ????? 01101 11", lui    , U, R(rd) = imm);
   INSTPAT("??????? ????? ????? ??? ????? 00101 11", auipc  , U, R(rd) = s->pc + imm);
 
-  INSTPAT(
-      "??????? ????? ????? ??? ????? 11011 11", jal, J, do {
-        s->dnpc = s->pc + imm;
-        R(rd) = s->pc + 4;
-      } while (0));
-  INSTPAT(
-      "??????? ????? ????? ??? ????? 11001 11", jalr, I, do {
-        s->dnpc = src1 + imm;
-        R(rd) = s->pc + 4;
-      } while (0));
-  INSTPAT("??????? ????? ????? 000 ????? 11000 11", beq, B,
-          do_branch(s, src1 == src2, imm));
-  INSTPAT("??????? ????? ????? 001 ????? 11000 11", bne, B,
-          do_branch(s, src1 != src2, imm));
-  INSTPAT("??????? ????? ????? 100 ????? 11000 11", blt, B,
-          do_branch(s, (sword_t)src1 < (sword_t)src2, imm));
-  INSTPAT("??????? ????? ????? 101 ????? 11000 11", bge, B,
-          do_branch(s, (sword_t)src1 >= (sword_t)src2, imm));
-  INSTPAT("??????? ????? ????? 110 ????? 11000 11", bltu, B,
-          do_branch(s, src1 < src2, imm));
-  INSTPAT("??????? ????? ????? 111 ????? 11000 11", bgeu, B,
-          do_branch(s, src1 >= src2, imm));
+  INSTPAT("??????? ????? ????? ??? ????? 11011 11", jal    , J, do {s->dnpc = s->pc + imm; R(rd) = s->pc + 4; } while(0));
+  INSTPAT("??????? ????? ????? ??? ????? 11001 11", jalr   , I, do {s->dnpc = src1 + imm; R(rd) = s->pc + 4; } while(0));
+  INSTPAT("??????? ????? ????? 000 ????? 11000 11", beq    , B, do_branch(s, src1 == src2, imm));
+  INSTPAT("??????? ????? ????? 001 ????? 11000 11", bne    , B, do_branch(s, src1 != src2, imm));
+  INSTPAT("??????? ????? ????? 100 ????? 11000 11", blt    , B, do_branch(s, (sword_t)src1 < (sword_t)src2, imm));
+  INSTPAT("??????? ????? ????? 101 ????? 11000 11", bge    , B, do_branch(s, (sword_t)src1 >= (sword_t)src2, imm));
+  INSTPAT("??????? ????? ????? 110 ????? 11000 11", bltu   , B, do_branch(s, src1 < src2, imm));
+  INSTPAT("??????? ????? ????? 111 ????? 11000 11", bgeu   , B, do_branch(s, src1 >= src2, imm));
 
   INSTPAT("??????? ????? ????? 000 ????? 00000 11", lb     , I, R(rd) = SEXT(Mr(src1 + imm, 1), 8));
   INSTPAT("??????? ????? ????? 001 ????? 00000 11", lh     , I, R(rd) = SEXT(Mr(src1 + imm, 2), 16));
@@ -135,14 +121,14 @@ 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();