diff --git a/tcg/s390/tcg-target.c b/tcg/s390/tcg-target.c
index 6988937..25c80e6 100644
--- a/tcg/s390/tcg-target.c
+++ b/tcg/s390/tcg-target.c
@@ -137,6 +137,7 @@ static const int tcg_target_call_iarg_regs[] = {
     TCG_REG_R3,
     TCG_REG_R4,
     TCG_REG_R5,
+    TCG_REG_R6,
 };
 
 static const int tcg_target_call_oarg_regs[] = {