diff --git a/src/engine/interpreter/fp.c b/src/engine/interpreter/fp.c
index a68420ea3..aef8b712e 100644
--- a/src/engine/interpreter/fp.c
+++ b/src/engine/interpreter/fp.c
@@ -99,6 +99,10 @@ def_rtl(fpcall, rtlreg_t *dest, const rtlreg_t *src1, const rtlreg_t *src2, uint
       case FPCALL_LT: *dest = f16_lt(fsrc1, fsrc2); break;
       case FPCALL_EQ: *dest = f16_eq(fsrc1, fsrc2); break;
 
+      case FPCALL_SGNJ:  *dest = fsgnj16(fsrc1, fsrc2, false, false); break;
+      case FPCALL_SGNJN: *dest = fsgnj16(fsrc1, fsrc2, true, false); break;
+      case FPCALL_SGNJX: *dest = fsgnj16(fsrc1, fsrc2, false, true); break;
+
       case FPCALL_I32ToF: *dest = my_i32_to_f16 (*src1).v; break;
       case FPCALL_U32ToF: *dest = my_ui32_to_f16(*src1).v; break;
       case FPCALL_I64ToF: *dest = my_i64_to_f16 (*src1).v; break;
diff --git a/src/isa/riscv64/instr/rvzfh/exec.h b/src/isa/riscv64/instr/rvzfh/exec.h
index 19e9948f7..31d6fadec 100644
--- a/src/isa/riscv64/instr/rvzfh/exec.h
+++ b/src/isa/riscv64/instr/rvzfh/exec.h
@@ -151,25 +151,17 @@ def_EHelper(fcvt_lu_h) {
 
 
 def_EHelper(fsgnjh) {
-  rtl_andi(s, s0, dsrc1, ~F16_SIGN);
-  rtl_andi(s, ddest, dsrc2, F16_SIGN);
-  rtl_or(s, ddest, s0, ddest);
+  rtl_hostcall(s, HOSTCALL_FP, ddest, dsrc1, dsrc2, FPCALL_CMD(FPCALL_SGNJ, FPCALL_W16));
   rtl_fsr(s, ddest, ddest, FPCALL_W16);
 }
 
 def_EHelper(fsgnjnh) {
-  rtl_andi(s, s0, dsrc1, ~F16_SIGN);
-  rtl_xori(s, ddest, dsrc2, F16_SIGN);
-  rtl_andi(s, ddest, ddest, F16_SIGN);
-  rtl_or(s, ddest, s0, ddest);
+  rtl_hostcall(s, HOSTCALL_FP, ddest, dsrc1, dsrc2, FPCALL_CMD(FPCALL_SGNJN, FPCALL_W16));
   rtl_fsr(s, ddest, ddest, FPCALL_W16);
 }
 
 def_EHelper(fsgnjxh) {
-  rtl_andi(s, s0, dsrc1, ~F16_SIGN);
-  rtl_xor(s, ddest, dsrc1, dsrc2);
-  rtl_andi(s, ddest, ddest, F16_SIGN);
-  rtl_or(s, ddest, s0, ddest);
+  rtl_hostcall(s, HOSTCALL_FP, ddest, dsrc1, dsrc2, FPCALL_CMD(FPCALL_SGNJX, FPCALL_W16));
   rtl_fsr(s, ddest, ddest, FPCALL_W16);
 }