[PATCH for-8.1 v4 13/25] target/riscv: put env->misa_ext <-> cpu->cfg code into helpers

[Daniel Henrique Barboza]

The extremely tedious code that sets cpu->cfg based on misa_ext, and
vice-versa, is scattered around riscv_cpu_validate_set_extensions() and
set_misa().

Introduce helpers to do this work, cleaning up the logic of both
functions a bit. While we're at it, add a note in cpu.h informing that
any future change in MISA RV* bits should also be reflected in the
helpers as well.

We'll want to keep env->misa_ext changes in sync with cpu->cfg during
realize() in the next patches, and both helpers will have a role to play
in that.

Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
---
 target/riscv/cpu.c | 120 ++++++++++++++++++++++++---------------------
 target/riscv/cpu.h |   3 +-
 2 files changed, 65 insertions(+), 58 deletions(-)

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index 0e56a1c01f..c4f18d0436 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -234,10 +234,69 @@ const char *riscv_cpu_get_trap_name(target_ulong cause, 
bool async)
     }
 }
 
-static void set_misa(CPURISCVState *env, RISCVMXL mxl, uint32_t ext)
+static uint32_t riscv_get_misa_ext_with_cpucfg(RISCVCPUConfig *cfg)
 {
-    RISCVCPU *cpu;
+    uint32_t ext = 0;
 
+    if (cfg->ext_i) {
+        ext |= RVI;
+    }
+    if (cfg->ext_e) {
+        ext |= RVE;
+    }
+    if (cfg->ext_m) {
+        ext |= RVM;
+    }
+    if (cfg->ext_a) {
+        ext |= RVA;
+    }
+    if (cfg->ext_f) {
+        ext |= RVF;
+    }
+    if (cfg->ext_d) {
+        ext |= RVD;
+    }
+    if (cfg->ext_c) {
+        ext |= RVC;
+    }
+    if (cfg->ext_s) {
+        ext |= RVS;
+    }
+    if (cfg->ext_u) {
+        ext |= RVU;
+    }
+    if (cfg->ext_h) {
+        ext |= RVH;
+    }
+    if (cfg->ext_v) {
+        ext |= RVV;
+    }
+    if (cfg->ext_j) {
+        ext |= RVJ;
+    }
+
+    return ext;
+}
+
+static void riscv_set_cpucfg_with_misa(RISCVCPUConfig *cfg,
+                                       uint32_t misa_ext)
+{
+    cfg->ext_i = misa_ext & RVI;
+    cfg->ext_e = misa_ext & RVE;
+    cfg->ext_m = misa_ext & RVM;
+    cfg->ext_a = misa_ext & RVA;
+    cfg->ext_f = misa_ext & RVF;
+    cfg->ext_d = misa_ext & RVD;
+    cfg->ext_v = misa_ext & RVV;
+    cfg->ext_c = misa_ext & RVC;
+    cfg->ext_s = misa_ext & RVS;
+    cfg->ext_u = misa_ext & RVU;
+    cfg->ext_h = misa_ext & RVH;
+    cfg->ext_j = misa_ext & RVJ;
+}
+
+static void set_misa(CPURISCVState *env, RISCVMXL mxl, uint32_t ext)
+{
     env->misa_mxl_max = env->misa_mxl = mxl;
     env->misa_ext_mask = env->misa_ext = ext;
 
@@ -251,25 +310,7 @@ static void set_misa(CPURISCVState *env, RISCVMXL mxl, 
uint32_t ext)
         return;
     }
 
-    /*
-     * We can't use riscv_cpu_cfg() in this case because it is
-     * a read-only inline and we're going to change the values
-     * of cpu->cfg.
-     */
-    cpu = env_archcpu(env);
-
-    cpu->cfg.ext_i = ext & RVI;
-    cpu->cfg.ext_e = ext & RVE;
-    cpu->cfg.ext_m = ext & RVM;
-    cpu->cfg.ext_a = ext & RVA;
-    cpu->cfg.ext_f = ext & RVF;
-    cpu->cfg.ext_d = ext & RVD;
-    cpu->cfg.ext_v = ext & RVV;
-    cpu->cfg.ext_c = ext & RVC;
-    cpu->cfg.ext_s = ext & RVS;
-    cpu->cfg.ext_u = ext & RVU;
-    cpu->cfg.ext_h = ext & RVH;
-    cpu->cfg.ext_j = ext & RVJ;
+    riscv_set_cpucfg_with_misa(&env_archcpu(env)->cfg, ext);
 }
 
 #ifndef CONFIG_USER_ONLY
@@ -1153,42 +1194,7 @@ static void riscv_cpu_validate_set_extensions(RISCVCPU 
*cpu, Error **errp)
      */
     riscv_cpu_disable_priv_spec_isa_exts(cpu);
 
-    if (cpu->cfg.ext_i) {
-        ext |= RVI;
-    }
-    if (cpu->cfg.ext_e) {
-        ext |= RVE;
-    }
-    if (cpu->cfg.ext_m) {
-        ext |= RVM;
-    }
-    if (cpu->cfg.ext_a) {
-        ext |= RVA;
-    }
-    if (cpu->cfg.ext_f) {
-        ext |= RVF;
-    }
-    if (cpu->cfg.ext_d) {
-        ext |= RVD;
-    }
-    if (cpu->cfg.ext_c) {
-        ext |= RVC;
-    }
-    if (cpu->cfg.ext_s) {
-        ext |= RVS;
-    }
-    if (cpu->cfg.ext_u) {
-        ext |= RVU;
-    }
-    if (cpu->cfg.ext_h) {
-        ext |= RVH;
-    }
-    if (cpu->cfg.ext_v) {
-        ext |= RVV;
-    }
-    if (cpu->cfg.ext_j) {
-        ext |= RVJ;
-    }
+    ext = riscv_get_misa_ext_with_cpucfg(&cpu->cfg);
 
     env->misa_ext_mask = env->misa_ext = ext;
 }
diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
index ebe0fff668..2263629332 100644
--- a/target/riscv/cpu.h
+++ b/target/riscv/cpu.h
@@ -66,7 +66,8 @@
 #define RV(x) ((target_ulong)1 << (x - 'A'))
 
 /*
- * Consider updating set_misa() when adding new
+ * Consider updating riscv_get_misa_ext_with_cpucfg()
+ * and riscv_set_cpucfg_with_misa() when adding new
  * MISA bits here.
  */
 #define RVI RV('I')
-- 
2.39.2