[PATCH 02/18] target/riscv: Correct the priority policy of riscv_csrrw_check()

[Bin Meng]

The priority policy of riscv_csrrw_check() was once adjusted in
commit eacaf4401956 ("target/riscv: Fix priority of csr related check in 
riscv_csrrw_check")
whose commit message says the CSR existence check should come
before the access control check, but the code changes did not
agree with the commit message, that the predicate() check came
after the read / write check.

Fixes: eacaf4401956 ("target/riscv: Fix priority of csr related check in 
riscv_csrrw_check")
Signed-off-by: Bin Meng <bm...@tinylab.org>
---

 target/riscv/csr.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index 1b0a0c1693..c2dd9d5af0 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -3793,15 +3793,15 @@ static inline RISCVException 
riscv_csrrw_check(CPURISCVState *env,
         return RISCV_EXCP_ILLEGAL_INST;
     }
 
-    if (write_mask && read_only) {
-        return RISCV_EXCP_ILLEGAL_INST;
-    }
-
     RISCVException ret = csr_ops[csrno].predicate(env, csrno);
     if (ret != RISCV_EXCP_NONE) {
         return ret;
     }
 
+    if (write_mask && read_only) {
+        return RISCV_EXCP_ILLEGAL_INST;
+    }
+
 #if !defined(CONFIG_USER_ONLY)
     int csr_priv, effective_priv = env->priv;
 
-- 
2.25.1