diff --git a/target/riscv/fpu_helper.c b/target/riscv/fpu_helper.c
index 4a5982d594..0895fa3c7e 100644
--- a/target/riscv/fpu_helper.c
+++ b/target/riscv/fpu_helper.c
@@ -98,9 +98,9 @@ static uint64_t do_fmadd_h(CPURISCVState *env, uint64_t rs1, uint64_t rs2,
 static uint64_t do_fmadd_s(CPURISCVState *env, uint64_t rs1, uint64_t rs2,
                            uint64_t rs3, int flags)
 {
-    float32 frs1 = check_nanbox_s(rs1);
-    float32 frs2 = check_nanbox_s(rs2);
-    float32 frs3 = check_nanbox_s(rs3);
+    float32 frs1 = check_nanbox_s(env, rs1);
+    float32 frs2 = check_nanbox_s(env, rs2);
+    float32 frs3 = check_nanbox_s(env, rs3);
     return nanbox_s(float32_muladd(frs1, frs2, frs3, flags, &env->fp_status));
 }
 
@@ -183,36 +183,36 @@ uint64_t helper_fnmadd_h(CPURISCVState *env, uint64_t frs1, uint64_t frs2,
 
 uint64_t helper_fadd_s(CPURISCVState *env, uint64_t rs1, uint64_t rs2)
 {
-    float32 frs1 = check_nanbox_s(rs1);
-    float32 frs2 = check_nanbox_s(rs2);
+    float32 frs1 = check_nanbox_s(env, rs1);
+    float32 frs2 = check_nanbox_s(env, rs2);
     return nanbox_s(float32_add(frs1, frs2, &env->fp_status));
 }
 
 uint64_t helper_fsub_s(CPURISCVState *env, uint64_t rs1, uint64_t rs2)
 {
-    float32 frs1 = check_nanbox_s(rs1);
-    float32 frs2 = check_nanbox_s(rs2);
+    float32 frs1 = check_nanbox_s(env, rs1);
+    float32 frs2 = check_nanbox_s(env, rs2);
     return nanbox_s(float32_sub(frs1, frs2, &env->fp_status));
 }
 
 uint64_t helper_fmul_s(CPURISCVState *env, uint64_t rs1, uint64_t rs2)
 {
-    float32 frs1 = check_nanbox_s(rs1);
-    float32 frs2 = check_nanbox_s(rs2);
+    float32 frs1 = check_nanbox_s(env, rs1);
+    float32 frs2 = check_nanbox_s(env, rs2);
     return nanbox_s(float32_mul(frs1, frs2, &env->fp_status));
 }
 
 uint64_t helper_fdiv_s(CPURISCVState *env, uint64_t rs1, uint64_t rs2)
 {
-    float32 frs1 = check_nanbox_s(rs1);
-    float32 frs2 = check_nanbox_s(rs2);
+    float32 frs1 = check_nanbox_s(env, rs1);
+    float32 frs2 = check_nanbox_s(env, rs2);
     return nanbox_s(float32_div(frs1, frs2, &env->fp_status));
 }
 
 uint64_t helper_fmin_s(CPURISCVState *env, uint64_t rs1, uint64_t rs2)
 {
-    float32 frs1 = check_nanbox_s(rs1);
-    float32 frs2 = check_nanbox_s(rs2);
+    float32 frs1 = check_nanbox_s(env, rs1);
+    float32 frs2 = check_nanbox_s(env, rs2);
     return nanbox_s(env->priv_ver < PRIV_VERSION_1_11_0 ?
                     float32_minnum(frs1, frs2, &env->fp_status) :
                     float32_minimum_number(frs1, frs2, &env->fp_status));
@@ -220,8 +220,8 @@ uint64_t helper_fmin_s(CPURISCVState *env, uint64_t rs1, uint64_t rs2)
 
 uint64_t helper_fmax_s(CPURISCVState *env, uint64_t rs1, uint64_t rs2)
 {
-    float32 frs1 = check_nanbox_s(rs1);
-    float32 frs2 = check_nanbox_s(rs2);
+    float32 frs1 = check_nanbox_s(env, rs1);
+    float32 frs2 = check_nanbox_s(env, rs2);
     return nanbox_s(env->priv_ver < PRIV_VERSION_1_11_0 ?
                     float32_maxnum(frs1, frs2, &env->fp_status) :
                     float32_maximum_number(frs1, frs2, &env->fp_status));
@@ -229,52 +229,52 @@ uint64_t helper_fmax_s(CPURISCVState *env, uint64_t rs1, uint64_t rs2)
 
 uint64_t helper_fsqrt_s(CPURISCVState *env, uint64_t rs1)
 {
-    float32 frs1 = check_nanbox_s(rs1);
+    float32 frs1 = check_nanbox_s(env, rs1);
     return nanbox_s(float32_sqrt(frs1, &env->fp_status));
 }
 
 target_ulong helper_fle_s(CPURISCVState *env, uint64_t rs1, uint64_t rs2)
 {
-    float32 frs1 = check_nanbox_s(rs1);
-    float32 frs2 = check_nanbox_s(rs2);
+    float32 frs1 = check_nanbox_s(env, rs1);
+    float32 frs2 = check_nanbox_s(env, rs2);
     return float32_le(frs1, frs2, &env->fp_status);
 }
 
 target_ulong helper_flt_s(CPURISCVState *env, uint64_t rs1, uint64_t rs2)
 {
-    float32 frs1 = check_nanbox_s(rs1);
-    float32 frs2 = check_nanbox_s(rs2);
+    float32 frs1 = check_nanbox_s(env, rs1);
+    float32 frs2 = check_nanbox_s(env, rs2);
     return float32_lt(frs1, frs2, &env->fp_status);
 }
 
 target_ulong helper_feq_s(CPURISCVState *env, uint64_t rs1, uint64_t rs2)
 {
-    float32 frs1 = check_nanbox_s(rs1);
-    float32 frs2 = check_nanbox_s(rs2);
+    float32 frs1 = check_nanbox_s(env, rs1);
+    float32 frs2 = check_nanbox_s(env, rs2);
     return float32_eq_quiet(frs1, frs2, &env->fp_status);
 }
 
 target_ulong helper_fcvt_w_s(CPURISCVState *env, uint64_t rs1)
 {
-    float32 frs1 = check_nanbox_s(rs1);
+    float32 frs1 = check_nanbox_s(env, rs1);
     return float32_to_int32(frs1, &env->fp_status);
 }
 
 target_ulong helper_fcvt_wu_s(CPURISCVState *env, uint64_t rs1)
 {
-    float32 frs1 = check_nanbox_s(rs1);
+    float32 frs1 = check_nanbox_s(env, rs1);
     return (int32_t)float32_to_uint32(frs1, &env->fp_status);
 }
 
 target_ulong helper_fcvt_l_s(CPURISCVState *env, uint64_t rs1)
 {
-    float32 frs1 = check_nanbox_s(rs1);
+    float32 frs1 = check_nanbox_s(env, rs1);
     return float32_to_int64(frs1, &env->fp_status);
 }
 
 target_ulong helper_fcvt_lu_s(CPURISCVState *env, uint64_t rs1)
 {
-    float32 frs1 = check_nanbox_s(rs1);
+    float32 frs1 = check_nanbox_s(env, rs1);
     return float32_to_uint64(frs1, &env->fp_status);
 }
 
@@ -298,9 +298,9 @@ uint64_t helper_fcvt_s_lu(CPURISCVState *env, target_ulong rs1)
     return nanbox_s(uint64_to_float32(rs1, &env->fp_status));
 }
 
-target_ulong helper_fclass_s(uint64_t rs1)
+target_ulong helper_fclass_s(CPURISCVState *env, uint64_t rs1)
 {
-    float32 frs1 = check_nanbox_s(rs1);
+    float32 frs1 = check_nanbox_s(env, rs1);
     return fclass_s(frs1);
 }
 
@@ -345,7 +345,7 @@ uint64_t helper_fcvt_s_d(CPURISCVState *env, uint64_t rs1)
 
 uint64_t helper_fcvt_d_s(CPURISCVState *env, uint64_t rs1)
 {
-    float32 frs1 = check_nanbox_s(rs1);
+    float32 frs1 = check_nanbox_s(env, rs1);
     return float32_to_float64(frs1, &env->fp_status);
 }
 
@@ -539,7 +539,7 @@ uint64_t helper_fcvt_h_lu(CPURISCVState *env, target_ulong rs1)
 
 uint64_t helper_fcvt_h_s(CPURISCVState *env, uint64_t rs1)
 {
-    float32 frs1 = check_nanbox_s(rs1);
+    float32 frs1 = check_nanbox_s(env, rs1);
     return nanbox_h(float32_to_float16(frs1, true, &env->fp_status));
 }
 
diff --git a/target/riscv/helper.h b/target/riscv/helper.h
index c15497e4a1..816acca993 100644
--- a/target/riscv/helper.h
+++ b/target/riscv/helper.h
@@ -38,7 +38,7 @@ DEF_HELPER_FLAGS_2(fcvt_s_w, TCG_CALL_NO_RWG, i64, env, tl)
 DEF_HELPER_FLAGS_2(fcvt_s_wu, TCG_CALL_NO_RWG, i64, env, tl)
 DEF_HELPER_FLAGS_2(fcvt_s_l, TCG_CALL_NO_RWG, i64, env, tl)
 DEF_HELPER_FLAGS_2(fcvt_s_lu, TCG_CALL_NO_RWG, i64, env, tl)
-DEF_HELPER_FLAGS_1(fclass_s, TCG_CALL_NO_RWG_SE, tl, i64)
+DEF_HELPER_FLAGS_2(fclass_s, TCG_CALL_NO_RWG_SE, tl, env, i64)
 
 /* Floating Point - Double Precision */
 DEF_HELPER_FLAGS_3(fadd_d, TCG_CALL_NO_RWG, i64, env, i64, i64)
diff --git a/target/riscv/insn_trans/trans_rvf.c.inc b/target/riscv/insn_trans/trans_rvf.c.inc
index b5459249c4..881e265222 100644
--- a/target/riscv/insn_trans/trans_rvf.c.inc
+++ b/target/riscv/insn_trans/trans_rvf.c.inc
@@ -20,7 +20,14 @@
 
 #define REQUIRE_FPU do {\
     if (ctx->mstatus_fs == 0) \
-        return false;                       \
+        if (!ctx->ext_zfinx) \
+            return false; \
+} while (0)
+
+#define REQUIRE_ZFINX_OR_F(ctx) do {\
+    if (!ctx->ext_zfinx) {\
+        REQUIRE_EXT(ctx, RVF); \
+    } \
 } while (0)
 
 static bool trans_flw(DisasContext *ctx, arg_flw *a)
@@ -70,10 +77,16 @@ static bool trans_fsw(DisasContext *ctx, arg_fsw *a)
 static bool trans_fmadd_s(DisasContext *ctx, arg_fmadd_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
+
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+    TCGv_i64 src2 = get_fpr_hs(ctx, a->rs2);
+    TCGv_i64 src3 = get_fpr_hs(ctx, a->rs3);
+
     gen_set_rm(ctx, a->rm);
-    gen_helper_fmadd_s(cpu_fpr[a->rd], cpu_env, cpu_fpr[a->rs1],
-                       cpu_fpr[a->rs2], cpu_fpr[a->rs3]);
+    gen_helper_fmadd_s(dest, cpu_env, src1, src2, src3);
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -81,10 +94,16 @@ static bool trans_fmadd_s(DisasContext *ctx, arg_fmadd_s *a)
 static bool trans_fmsub_s(DisasContext *ctx, arg_fmsub_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
+
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+    TCGv_i64 src2 = get_fpr_hs(ctx, a->rs2);
+    TCGv_i64 src3 = get_fpr_hs(ctx, a->rs3);
+
     gen_set_rm(ctx, a->rm);
-    gen_helper_fmsub_s(cpu_fpr[a->rd], cpu_env, cpu_fpr[a->rs1],
-                       cpu_fpr[a->rs2], cpu_fpr[a->rs3]);
+    gen_helper_fmsub_s(dest, cpu_env, src1, src2, src3);
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -92,10 +111,16 @@ static bool trans_fmsub_s(DisasContext *ctx, arg_fmsub_s *a)
 static bool trans_fnmsub_s(DisasContext *ctx, arg_fnmsub_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
+
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+    TCGv_i64 src2 = get_fpr_hs(ctx, a->rs2);
+    TCGv_i64 src3 = get_fpr_hs(ctx, a->rs3);
+
     gen_set_rm(ctx, a->rm);
-    gen_helper_fnmsub_s(cpu_fpr[a->rd], cpu_env, cpu_fpr[a->rs1],
-                        cpu_fpr[a->rs2], cpu_fpr[a->rs3]);
+    gen_helper_fnmsub_s(dest, cpu_env, src1, src2, src3);
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -103,10 +128,16 @@ static bool trans_fnmsub_s(DisasContext *ctx, arg_fnmsub_s *a)
 static bool trans_fnmadd_s(DisasContext *ctx, arg_fnmadd_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
+
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+    TCGv_i64 src2 = get_fpr_hs(ctx, a->rs2);
+    TCGv_i64 src3 = get_fpr_hs(ctx, a->rs3);
+
     gen_set_rm(ctx, a->rm);
-    gen_helper_fnmadd_s(cpu_fpr[a->rd], cpu_env, cpu_fpr[a->rs1],
-                        cpu_fpr[a->rs2], cpu_fpr[a->rs3]);
+    gen_helper_fnmadd_s(dest, cpu_env, src1, src2, src3);
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -114,11 +145,15 @@ static bool trans_fnmadd_s(DisasContext *ctx, arg_fnmadd_s *a)
 static bool trans_fadd_s(DisasContext *ctx, arg_fadd_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
+
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+    TCGv_i64 src2 = get_fpr_hs(ctx, a->rs2);
 
     gen_set_rm(ctx, a->rm);
-    gen_helper_fadd_s(cpu_fpr[a->rd], cpu_env,
-                      cpu_fpr[a->rs1], cpu_fpr[a->rs2]);
+    gen_helper_fadd_s(dest, cpu_env, src1, src2);
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -126,11 +161,15 @@ static bool trans_fadd_s(DisasContext *ctx, arg_fadd_s *a)
 static bool trans_fsub_s(DisasContext *ctx, arg_fsub_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
+
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+    TCGv_i64 src2 = get_fpr_hs(ctx, a->rs2);
 
     gen_set_rm(ctx, a->rm);
-    gen_helper_fsub_s(cpu_fpr[a->rd], cpu_env,
-                      cpu_fpr[a->rs1], cpu_fpr[a->rs2]);
+    gen_helper_fsub_s(dest, cpu_env, src1, src2);
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -138,11 +177,15 @@ static bool trans_fsub_s(DisasContext *ctx, arg_fsub_s *a)
 static bool trans_fmul_s(DisasContext *ctx, arg_fmul_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
+
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+    TCGv_i64 src2 = get_fpr_hs(ctx, a->rs2);
 
     gen_set_rm(ctx, a->rm);
-    gen_helper_fmul_s(cpu_fpr[a->rd], cpu_env,
-                      cpu_fpr[a->rs1], cpu_fpr[a->rs2]);
+    gen_helper_fmul_s(dest, cpu_env, src1, src2);
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -150,11 +193,15 @@ static bool trans_fmul_s(DisasContext *ctx, arg_fmul_s *a)
 static bool trans_fdiv_s(DisasContext *ctx, arg_fdiv_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
+
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+    TCGv_i64 src2 = get_fpr_hs(ctx, a->rs2);
 
     gen_set_rm(ctx, a->rm);
-    gen_helper_fdiv_s(cpu_fpr[a->rd], cpu_env,
-                      cpu_fpr[a->rs1], cpu_fpr[a->rs2]);
+    gen_helper_fdiv_s(dest, cpu_env, src1, src2);
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -162,10 +209,14 @@ static bool trans_fdiv_s(DisasContext *ctx, arg_fdiv_s *a)
 static bool trans_fsqrt_s(DisasContext *ctx, arg_fsqrt_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
+
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
 
     gen_set_rm(ctx, a->rm);
-    gen_helper_fsqrt_s(cpu_fpr[a->rd], cpu_env, cpu_fpr[a->rs1]);
+    gen_helper_fsqrt_s(dest, cpu_env, src1);
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -173,22 +224,40 @@ static bool trans_fsqrt_s(DisasContext *ctx, arg_fsqrt_s *a)
 static bool trans_fsgnj_s(DisasContext *ctx, arg_fsgnj_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
     if (a->rs1 == a->rs2) { /* FMOV */
-        gen_check_nanbox_s(cpu_fpr[a->rd], cpu_fpr[a->rs1]);
+        TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+        if (ctx->ext_zfinx) {
+            gen_nanbox_s(dest, src1);
+        } else {
+            gen_check_nanbox_s(dest, src1);
+        }
     } else { /* FSGNJ */
-        TCGv_i64 rs1 = tcg_temp_new_i64();
-        TCGv_i64 rs2 = tcg_temp_new_i64();
-
-        gen_check_nanbox_s(rs1, cpu_fpr[a->rs1]);
-        gen_check_nanbox_s(rs2, cpu_fpr[a->rs2]);
-
-        /* This formulation retains the nanboxing of rs2. */
-        tcg_gen_deposit_i64(cpu_fpr[a->rd], rs2, rs1, 0, 31);
-        tcg_temp_free_i64(rs1);
-        tcg_temp_free_i64(rs2);
+        TCGv_i64 rs1, rs2;
+        if (!ctx->ext_zfinx) {
+            TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+            TCGv_i64 src2 = get_fpr_hs(ctx, a->rs2);
+            rs1 = tcg_temp_new_i64();
+            rs2 = tcg_temp_new_i64();
+            gen_check_nanbox_s(rs1, src1);
+            gen_check_nanbox_s(rs2, src2);
+        } else {
+            rs1 = get_fpr_hs(ctx, a->rs1);
+            rs2 = get_fpr_hs(ctx, a->rs2);
+        }
+
+        /* This formulation retains the nanboxing of rs2 in normal 'F'. */
+        tcg_gen_deposit_i64(dest, rs2, rs1, 0, 31);
+        if (!ctx->ext_zfinx) {
+            tcg_temp_free_i64(rs1);
+            tcg_temp_free_i64(rs2);
+        } else {
+            gen_nanbox_s(dest, dest);
+        }
     }
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -198,16 +267,27 @@ static bool trans_fsgnjn_s(DisasContext *ctx, arg_fsgnjn_s *a)
     TCGv_i64 rs1, rs2, mask;
 
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
-    rs1 = tcg_temp_new_i64();
-    gen_check_nanbox_s(rs1, cpu_fpr[a->rs1]);
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
+    if (!ctx->ext_zfinx) {
+        TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+        rs1 = tcg_temp_new_i64();
+        gen_check_nanbox_s(rs1, src1);
+    } else {
+        rs1 = get_fpr_hs(ctx, a->rs1);
+    }
 
     if (a->rs1 == a->rs2) { /* FNEG */
-        tcg_gen_xori_i64(cpu_fpr[a->rd], rs1, MAKE_64BIT_MASK(31, 1));
+        tcg_gen_xori_i64(dest, rs1, MAKE_64BIT_MASK(31, 1));
     } else {
+        TCGv_i64 src2 = get_fpr_hs(ctx, a->rs2);
         rs2 = tcg_temp_new_i64();
-        gen_check_nanbox_s(rs2, cpu_fpr[a->rs2]);
+        if (!ctx->ext_zfinx) {
+            gen_check_nanbox_s(rs2, src2);
+        } else {
+            tcg_gen_mov_i64(rs2, src2);
+        }
 
         /*
          * Replace bit 31 in rs1 with inverse in rs2.
@@ -215,13 +295,17 @@ static bool trans_fsgnjn_s(DisasContext *ctx, arg_fsgnjn_s *a)
          */
         mask = tcg_constant_i64(~MAKE_64BIT_MASK(31, 1));
         tcg_gen_nor_i64(rs2, rs2, mask);
-        tcg_gen_and_i64(rs1, mask, rs1);
-        tcg_gen_or_i64(cpu_fpr[a->rd], rs1, rs2);
-
+        tcg_gen_and_i64(dest, mask, rs1);
+        tcg_gen_or_i64(dest, dest, rs2);
+        
         tcg_temp_free_i64(rs2);
     }
-    tcg_temp_free_i64(rs1);
-
+    if (ctx->ext_zfinx) {
+        gen_nanbox_s(dest, dest);
+    } else {
+        tcg_temp_free_i64(rs1);
+    }
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -231,28 +315,44 @@ static bool trans_fsgnjx_s(DisasContext *ctx, arg_fsgnjx_s *a)
     TCGv_i64 rs1, rs2;
 
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
-    rs1 = tcg_temp_new_i64();
-    gen_check_nanbox_s(rs1, cpu_fpr[a->rs1]);
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
+    if (!ctx->ext_zfinx) {
+        TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+        rs1 = tcg_temp_new_i64();
+        gen_check_nanbox_s(rs1, src1);
+    } else {
+        rs1 = get_fpr_hs(ctx, a->rs1);
+    }
 
     if (a->rs1 == a->rs2) { /* FABS */
-        tcg_gen_andi_i64(cpu_fpr[a->rd], rs1, ~MAKE_64BIT_MASK(31, 1));
+        tcg_gen_andi_i64(dest, rs1, ~MAKE_64BIT_MASK(31, 1));
     } else {
-        rs2 = tcg_temp_new_i64();
-        gen_check_nanbox_s(rs2, cpu_fpr[a->rs2]);
+        if (!ctx->ext_zfinx) {
+            TCGv_i64 src2 = get_fpr_hs(ctx, a->rs2);
+            rs2 = tcg_temp_new_i64();
+            gen_check_nanbox_s(rs2, src2);
+        } else {
+            rs2 = get_fpr_hs(ctx, a->rs2);
+        }
 
         /*
          * Xor bit 31 in rs1 with that in rs2.
          * This formulation retains the nanboxing of rs1.
          */
-        tcg_gen_andi_i64(rs2, rs2, MAKE_64BIT_MASK(31, 1));
-        tcg_gen_xor_i64(cpu_fpr[a->rd], rs1, rs2);
-
-        tcg_temp_free_i64(rs2);
+        tcg_gen_andi_i64(dest, rs2, MAKE_64BIT_MASK(31, 1));
+        tcg_gen_xor_i64(dest, rs1, dest);
+        if (!ctx->ext_zfinx) {
+            tcg_temp_free_i64(rs2);
+        }
     }
-    tcg_temp_free_i64(rs1);
-
+    if (ctx->ext_zfinx) {
+        gen_nanbox_s(dest, dest);
+    } else {
+        tcg_temp_free_i64(rs1);
+    }
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -260,10 +360,14 @@ static bool trans_fsgnjx_s(DisasContext *ctx, arg_fsgnjx_s *a)
 static bool trans_fmin_s(DisasContext *ctx, arg_fmin_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
-    gen_helper_fmin_s(cpu_fpr[a->rd], cpu_env, cpu_fpr[a->rs1],
-                      cpu_fpr[a->rs2]);
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+    TCGv_i64 src2 = get_fpr_hs(ctx, a->rs2);
+
+    gen_helper_fmin_s(dest, cpu_env, src1, src2);
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -271,10 +375,14 @@ static bool trans_fmin_s(DisasContext *ctx, arg_fmin_s *a)
 static bool trans_fmax_s(DisasContext *ctx, arg_fmax_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
-    gen_helper_fmax_s(cpu_fpr[a->rd], cpu_env, cpu_fpr[a->rs1],
-                      cpu_fpr[a->rs2]);
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+    TCGv_i64 src2 = get_fpr_hs(ctx, a->rs2);
+
+    gen_helper_fmax_s(dest, cpu_env, src1, src2);
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -282,12 +390,13 @@ static bool trans_fmax_s(DisasContext *ctx, arg_fmax_s *a)
 static bool trans_fcvt_w_s(DisasContext *ctx, arg_fcvt_w_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
     TCGv dest = dest_gpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
 
     gen_set_rm(ctx, a->rm);
-    gen_helper_fcvt_w_s(dest, cpu_env, cpu_fpr[a->rs1]);
+    gen_helper_fcvt_w_s(dest, cpu_env, src1);
     gen_set_gpr(ctx, a->rd, dest);
     return true;
 }
@@ -295,12 +404,13 @@ static bool trans_fcvt_w_s(DisasContext *ctx, arg_fcvt_w_s *a)
 static bool trans_fcvt_wu_s(DisasContext *ctx, arg_fcvt_wu_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
     TCGv dest = dest_gpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
 
     gen_set_rm(ctx, a->rm);
-    gen_helper_fcvt_wu_s(dest, cpu_env, cpu_fpr[a->rs1]);
+    gen_helper_fcvt_wu_s(dest, cpu_env, src1);
     gen_set_gpr(ctx, a->rd, dest);
     return true;
 }
@@ -309,14 +419,14 @@ static bool trans_fmv_x_w(DisasContext *ctx, arg_fmv_x_w *a)
 {
     /* NOTE: This was FMV.X.S in an earlier version of the ISA spec! */
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
     TCGv dest = dest_gpr(ctx, a->rd);
-
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
 #if defined(TARGET_RISCV64)
-    tcg_gen_ext32s_tl(dest, cpu_fpr[a->rs1]);
+    tcg_gen_ext32s_tl(dest, src1);
 #else
-    tcg_gen_extrl_i64_i32(dest, cpu_fpr[a->rs1]);
+    tcg_gen_extrl_i64_i32(dest, src1);
 #endif
 
     gen_set_gpr(ctx, a->rd, dest);
@@ -326,11 +436,13 @@ static bool trans_fmv_x_w(DisasContext *ctx, arg_fmv_x_w *a)
 static bool trans_feq_s(DisasContext *ctx, arg_feq_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
     TCGv dest = dest_gpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+    TCGv_i64 src2 = get_fpr_hs(ctx, a->rs2);
 
-    gen_helper_feq_s(dest, cpu_env, cpu_fpr[a->rs1], cpu_fpr[a->rs2]);
+    gen_helper_feq_s(dest, cpu_env, src1, src2);
     gen_set_gpr(ctx, a->rd, dest);
     return true;
 }
@@ -338,11 +450,13 @@ static bool trans_feq_s(DisasContext *ctx, arg_feq_s *a)
 static bool trans_flt_s(DisasContext *ctx, arg_flt_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
     TCGv dest = dest_gpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+    TCGv_i64 src2 = get_fpr_hs(ctx, a->rs2);
 
-    gen_helper_flt_s(dest, cpu_env, cpu_fpr[a->rs1], cpu_fpr[a->rs2]);
+    gen_helper_flt_s(dest, cpu_env, src1, src2);
     gen_set_gpr(ctx, a->rd, dest);
     return true;
 }
@@ -350,11 +464,13 @@ static bool trans_flt_s(DisasContext *ctx, arg_flt_s *a)
 static bool trans_fle_s(DisasContext *ctx, arg_fle_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
     TCGv dest = dest_gpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
+    TCGv_i64 src2 = get_fpr_hs(ctx, a->rs2);
 
-    gen_helper_fle_s(dest, cpu_env, cpu_fpr[a->rs1], cpu_fpr[a->rs2]);
+    gen_helper_fle_s(dest, cpu_env, src1, src2);
     gen_set_gpr(ctx, a->rd, dest);
     return true;
 }
@@ -362,11 +478,12 @@ static bool trans_fle_s(DisasContext *ctx, arg_fle_s *a)
 static bool trans_fclass_s(DisasContext *ctx, arg_fclass_s *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
     TCGv dest = dest_gpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
 
-    gen_helper_fclass_s(dest, cpu_fpr[a->rs1]);
+    gen_helper_fclass_s(dest, cpu_env, src1);
     gen_set_gpr(ctx, a->rd, dest);
     return true;
 }
@@ -374,13 +491,14 @@ static bool trans_fclass_s(DisasContext *ctx, arg_fclass_s *a)
 static bool trans_fcvt_s_w(DisasContext *ctx, arg_fcvt_s_w *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
     TCGv src = get_gpr(ctx, a->rs1, EXT_SIGN);
 
     gen_set_rm(ctx, a->rm);
-    gen_helper_fcvt_s_w(cpu_fpr[a->rd], cpu_env, src);
-
+    gen_helper_fcvt_s_w(dest, cpu_env, src);
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -388,13 +506,14 @@ static bool trans_fcvt_s_w(DisasContext *ctx, arg_fcvt_s_w *a)
 static bool trans_fcvt_s_wu(DisasContext *ctx, arg_fcvt_s_wu *a)
 {
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
     TCGv src = get_gpr(ctx, a->rs1, EXT_ZERO);
 
     gen_set_rm(ctx, a->rm);
-    gen_helper_fcvt_s_wu(cpu_fpr[a->rd], cpu_env, src);
-
+    gen_helper_fcvt_s_wu(dest, cpu_env, src);
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -403,13 +522,14 @@ static bool trans_fmv_w_x(DisasContext *ctx, arg_fmv_w_x *a)
 {
     /* NOTE: This was FMV.S.X in an earlier version of the ISA spec! */
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
     TCGv src = get_gpr(ctx, a->rs1, EXT_ZERO);
 
-    tcg_gen_extu_tl_i64(cpu_fpr[a->rd], src);
-    gen_nanbox_s(cpu_fpr[a->rd], cpu_fpr[a->rd]);
-
+    tcg_gen_extu_tl_i64(dest, src);
+    gen_nanbox_s(dest, dest);
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -418,12 +538,13 @@ static bool trans_fcvt_l_s(DisasContext *ctx, arg_fcvt_l_s *a)
 {
     REQUIRE_64BIT(ctx);
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
     TCGv dest = dest_gpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
 
     gen_set_rm(ctx, a->rm);
-    gen_helper_fcvt_l_s(dest, cpu_env, cpu_fpr[a->rs1]);
+    gen_helper_fcvt_l_s(dest, cpu_env, src1);
     gen_set_gpr(ctx, a->rd, dest);
     return true;
 }
@@ -432,12 +553,13 @@ static bool trans_fcvt_lu_s(DisasContext *ctx, arg_fcvt_lu_s *a)
 {
     REQUIRE_64BIT(ctx);
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
     TCGv dest = dest_gpr(ctx, a->rd);
+    TCGv_i64 src1 = get_fpr_hs(ctx, a->rs1);
 
     gen_set_rm(ctx, a->rm);
-    gen_helper_fcvt_lu_s(dest, cpu_env, cpu_fpr[a->rs1]);
+    gen_helper_fcvt_lu_s(dest, cpu_env, src1);
     gen_set_gpr(ctx, a->rd, dest);
     return true;
 }
@@ -446,13 +568,14 @@ static bool trans_fcvt_s_l(DisasContext *ctx, arg_fcvt_s_l *a)
 {
     REQUIRE_64BIT(ctx);
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
     TCGv src = get_gpr(ctx, a->rs1, EXT_SIGN);
 
     gen_set_rm(ctx, a->rm);
-    gen_helper_fcvt_s_l(cpu_fpr[a->rd], cpu_env, src);
-
+    gen_helper_fcvt_s_l(dest, cpu_env, src);
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
@@ -461,13 +584,14 @@ static bool trans_fcvt_s_lu(DisasContext *ctx, arg_fcvt_s_lu *a)
 {
     REQUIRE_64BIT(ctx);
     REQUIRE_FPU;
-    REQUIRE_EXT(ctx, RVF);
+    REQUIRE_ZFINX_OR_F(ctx);
 
+    TCGv_i64 dest = dest_fpr(ctx, a->rd);
     TCGv src = get_gpr(ctx, a->rs1, EXT_ZERO);
 
     gen_set_rm(ctx, a->rm);
-    gen_helper_fcvt_s_lu(cpu_fpr[a->rd], cpu_env, src);
-
+    gen_helper_fcvt_s_lu(dest, cpu_env, src);
+    gen_set_fpr_hs(ctx, a->rd, dest);
     mark_fs_dirty(ctx);
     return true;
 }
diff --git a/target/riscv/internals.h b/target/riscv/internals.h
index 065e8162a2..9f3f3319f2 100644
--- a/target/riscv/internals.h
+++ b/target/riscv/internals.h
@@ -51,8 +51,12 @@ static inline uint64_t nanbox_s(float32 f)
     return f | MAKE_64BIT_MASK(32, 32);
 }
 
-static inline float32 check_nanbox_s(uint64_t f)
+static inline float32 check_nanbox_s(CPURISCVState *env, uint64_t f)
 {
+    /* Disable nanbox check when enable zfinx */
+    if (RISCV_CPU(env_cpu(env))->cfg.ext_zfinx)
+        return (uint32_t)f;
+
     uint64_t mask = MAKE_64BIT_MASK(32, 32);
 
     if (likely((f & mask) == mask)) {
