Re: [PATCH 1/2] target/riscv: Add set_implicit_extensions_from_ext() function

[Daniel Henrique Barboza]

On 4/10/23 00:35, Weiwei Li wrote:

Move multi-letter extensions that may implicitly enabled from misa.EXT
alone to prepare for following separation of implicitly enabled and
explicitly enabled extensions.

Signed-off-by: Weiwei Li <liwei...@iscas.ac.cn>
Signed-off-by: Junqiang Wang <wangjunqi...@iscas.ac.cn>
---

Regardless of what we end up doing with patch 2 I believe this is a good
separation to have.


Reviewed-by: Daniel Henrique Barboza <dbarb...@ventanamicro.com>

  target/riscv/cpu.c | 56 +++++++++++++++++++++++++---------------------
  1 file changed, 31 insertions(+), 25 deletions(-)

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index cb68916fce..abb65d41b1 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -809,6 +809,35 @@ static void riscv_cpu_disas_set_info(CPUState *s, 
disassemble_info *info)
      }
  }

+static void set_implicit_extensions_from_ext(RISCVCPU *cpu)

+{
+
+    /* The V vector extension depends on the Zve64d extension */
+    if (cpu->cfg.ext_v) {
+        cpu->cfg.ext_zve64d = true;
+    }
+
+    /* The Zve64d extension depends on the Zve64f extension */
+    if (cpu->cfg.ext_zve64d) {
+        cpu->cfg.ext_zve64f = true;
+    }
+
+    /* The Zve64f extension depends on the Zve32f extension */
+    if (cpu->cfg.ext_zve64f) {
+        cpu->cfg.ext_zve32f = true;
+    }
+
+    if (cpu->cfg.ext_c) {
+        cpu->cfg.ext_zca = true;
+        if (cpu->cfg.ext_f && cpu->env.misa_mxl_max == MXL_RV32) {
+            cpu->cfg.ext_zcf = true;
+        }
+        if (cpu->cfg.ext_d) {
+            cpu->cfg.ext_zcd = true;
+        }
+    }
+}
+
  /*
   * Check consistency between chosen extensions while setting
   * cpu->cfg accordingly, doing a set_misa() in the end.
@@ -833,6 +862,8 @@ static void riscv_cpu_validate_set_extensions(RISCVCPU 
*cpu, Error **errp)
          cpu->cfg.ext_ifencei = true;
      }

+ set_implicit_extensions_from_ext(cpu);

+
      if (cpu->cfg.ext_i && cpu->cfg.ext_e) {
          error_setg(errp,
                     "I and E extensions are incompatible");
@@ -886,21 +917,6 @@ static void riscv_cpu_validate_set_extensions(RISCVCPU 
*cpu, Error **errp)
          return;
      }

- /* The V vector extension depends on the Zve64d extension */

-    if (cpu->cfg.ext_v) {
-        cpu->cfg.ext_zve64d = true;
-    }
-
-    /* The Zve64d extension depends on the Zve64f extension */
-    if (cpu->cfg.ext_zve64d) {
-        cpu->cfg.ext_zve64f = true;
-    }
-
-    /* The Zve64f extension depends on the Zve32f extension */
-    if (cpu->cfg.ext_zve64f) {
-        cpu->cfg.ext_zve32f = true;
-    }
-
      if (cpu->cfg.ext_zve64d && !cpu->cfg.ext_d) {
          error_setg(errp, "Zve64d/V extensions require D extension");
          return;
@@ -956,16 +972,6 @@ static void riscv_cpu_validate_set_extensions(RISCVCPU 
*cpu, Error **errp)
          }
      }

- if (cpu->cfg.ext_c) {

-        cpu->cfg.ext_zca = true;
-        if (cpu->cfg.ext_f && env->misa_mxl_max == MXL_RV32) {
-            cpu->cfg.ext_zcf = true;
-        }
-        if (cpu->cfg.ext_d) {
-            cpu->cfg.ext_zcd = true;
-        }
-    }
-
      if (env->misa_mxl_max != MXL_RV32 && cpu->cfg.ext_zcf) {
          error_setg(errp, "Zcf extension is only relevant to RV32");
          return;