target/riscv: Extract virt enabled state from tb flags

Virt enabled state is not a constant, so we should put it into tb flags.
Thus we can use it like a constant condition at translation phase.

Reported-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn>
Message-Id: <20230324143031.1093-2-zhiwei_liu@linux.alibaba.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Tested-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-Id: <20230325105429.1142530-2-richard.henderson@linaro.org>
Message-Id: <20230412114333.118895-2-richard.henderson@linaro.org>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

target/riscv/cpu.h

@@ -648,6 +648,8 @@ FIELD(TB_FLAGS, VTA, 24, 1)
 FIELD(TB_FLAGS, VMA, 25, 1)
 /* Native debug itrigger */
 FIELD(TB_FLAGS, ITRIGGER, 26, 1)
+/* Virtual mode enabled */
+FIELD(TB_FLAGS, VIRT_ENABLED, 27, 1)
 
 #ifdef TARGET_RISCV32
 #define riscv_cpu_mxl(env)  ((void)(env), MXL_RV32)

target/riscv/cpu_helper.c

@@ -104,6 +104,7 @@ void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
 
         flags = FIELD_DP32(flags, TB_FLAGS, MSTATUS_HS_VS,
                            get_field(env->mstatus_hs, MSTATUS_VS));
+        flags = FIELD_DP32(flags, TB_FLAGS, VIRT_ENABLED, env->virt_enabled);
     }
     if (cpu->cfg.debug && !icount_enabled()) {
         flags = FIELD_DP32(flags, TB_FLAGS, ITRIGGER, env->itrigger_enabled);

target/riscv/translate.c

@@ -1171,15 +1171,7 @@ static void riscv_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs)
     ctx->mstatus_fs = tb_flags & TB_FLAGS_MSTATUS_FS;
     ctx->mstatus_vs = tb_flags & TB_FLAGS_MSTATUS_VS;
     ctx->priv_ver = env->priv_ver;
-#if !defined(CONFIG_USER_ONLY)
-    if (riscv_has_ext(env, RVH)) {
-        ctx->virt_enabled = env->virt_enabled;
-    } else {
-        ctx->virt_enabled = false;
-    }
-#else
-    ctx->virt_enabled = false;
-#endif
+    ctx->virt_enabled = FIELD_EX32(tb_flags, TB_FLAGS, VIRT_ENABLED);
     ctx->misa_ext = env->misa_ext;
     ctx->frm = -1;  /* unknown rounding mode */
     ctx->cfg_ptr = &(cpu->cfg);