diff --git a/src/hotspot/cpu/riscv/riscv.ad b/src/hotspot/cpu/riscv/riscv.ad
index 7bfff4b2086..e022dcb4262 100644
--- a/src/hotspot/cpu/riscv/riscv.ad
+++ b/src/hotspot/cpu/riscv/riscv.ad
@@ -1105,8 +1105,9 @@ void reg_mask_init() {
   _NO_SPECIAL_PTR_REG_mask.assignFrom(_ALL_REG_mask);
   _NO_SPECIAL_PTR_REG_mask.subtract(_NON_ALLOCATABLE_REG_mask);
 
-  // x27 is not allocatable when compressed oops is on
-  if (UseCompressedOops) {
+  // x27 is not allocatable when compressed oops is on and heapbase is not zero,
+  // compressed klass pointers doesn't use x27 when heapbase is zero.
+  if (UseCompressedOops && (CompressedOops::base() != nullptr)) {
     _NO_SPECIAL_REG32_mask.remove(OptoReg::as_OptoReg(x27->as_VMReg()));
     _NO_SPECIAL_REG_mask.remove(OptoReg::as_OptoReg(x27->as_VMReg()));
     _NO_SPECIAL_PTR_REG_mask.remove(OptoReg::as_OptoReg(x27->as_VMReg()));