diff --git a/nemu/src/isa/riscv32/inst.c b/nemu/src/isa/riscv32/inst.c
index 4065268..ede3377 100644
--- a/nemu/src/isa/riscv32/inst.c
+++ b/nemu/src/isa/riscv32/inst.c
@@ -32,9 +32,9 @@ enum {
 #define src2R() do { *src2 = R(rs2); } while (0)
 #define immI() do { *imm = SEXT(BITS(i, 31, 20), 12); } while(0)
 #define immU() do { *imm = SEXT(BITS(i, 31, 12), 20) << 12; } while(0)
-#define immS() do { *imm = (SEXT(BITS(i, 31, 25), 7) << 5) | BITS(i, 11, 7); } while(0)
-#define immB() do { *imm = (SEXT(BITS(i, 31, 31), 1) << 12 | BITS(i, 30, 25) << 5 | BITS(i, 11, 8) << 1 | BITS(i, 8, 8) << 11); } while(0)
-#define immJ() do { *imm = (SEXT(BITS(i, 31, 31), 1) << 20) | BITS(i, 30, 21) << 1 | BITS(i, 20, 20) << 11 | BITS(i, 19, 12) << 12; } while(0)
+#define immS() do { *imm = SEXT(BITS(i, 31, 25), 7) << 5 | BITS(i, 11, 7); } while(0)
+#define immB() do { *imm = SEXT(BITS(i, 31, 31), 1) << 12 | BITS(i, 30, 25) << 5 | BITS(i, 11, 8) << 1 | BITS(i, 7, 7) << 11; } while(0)
+#define immJ() do { *imm = SEXT(BITS(i, 31, 31), 1) << 20 | BITS(i, 30, 21) << 1 | BITS(i, 20, 20) << 11 | BITS(i, 19, 12) << 12; } while(0)
 
 static void decode_operand(Decode *s, int *rd, word_t *src1, word_t *src2, word_t *imm, int type) {
   uint32_t i = s->isa.inst.val;