diff --git a/tcg/mips/tcg-target.inc.c b/tcg/mips/tcg-target.inc.c
index a06ff257fafa663b11a3260bfe53b52e048f346b..be0bc92e8e7b0b33df45a37fa4e31670bde81bc0 100644
--- a/tcg/mips/tcg-target.inc.c
+++ b/tcg/mips/tcg-target.inc.c
@@ -792,7 +792,7 @@ static void tcg_out_addsub2(TCGContext *s, TCGReg rl, TCGReg rh, TCGReg al,
             tcg_out_opc_imm(s, OPC_ADDIU, rl, al, bl);
             tcg_out_opc_imm(s, OPC_SLTIU, TCG_TMP0, rl, bl);
         } else if (rl == al && rl == bl) {
-            tcg_out_opc_sa(s, OPC_SRL, TCG_TMP0, al, 31);
+            tcg_out_opc_sa(s, OPC_SRL, TCG_TMP0, al, TCG_TARGET_REG_BITS - 1);
             tcg_out_opc_reg(s, OPC_ADDU, rl, al, bl);
         } else {
             tcg_out_opc_reg(s, OPC_ADDU, rl, al, bl);