[PATCH v3 2/7] target/riscv: riscv_tr_init_disas_context: copy pointer-to-cfg into cfg_ptr

[Philipp Tomsich]

As the number of extensions is growing, copying them individiually
into the DisasContext will scale less and less... instead we populate
a pointer to the RISCVCPUConfig structure in the DisasContext.

This adds an extra indirection when checking for the availability of
an extension (compared to copying the fields into DisasContext).
While not a performance problem today, we can always (shallow) copy
the entire structure into the DisasContext (instead of putting a
pointer to it) if this is ever deemed necessary.

Signed-off-by: Philipp Tomsich <philipp.tomsich@vrull.eu>
Suggested-by: Richard Henderson <richard.henderson@linaro.org>

---

Changes in v3:
- (new patch) copy pointer to element cfg into DisasContext

 target/riscv/translate.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/target/riscv/translate.c b/target/riscv/translate.c
index f0bbe80875..22d09af2df 100644
--- a/target/riscv/translate.c
+++ b/target/riscv/translate.c
@@ -76,6 +76,7 @@ typedef struct DisasContext {
     int frm;
     RISCVMXL ol;
     bool virt_enabled;
+    const struct RISCVCPUConfig *cfg_ptr;
     bool ext_ifencei;
     bool ext_zfh;
     bool ext_zfhmin;
@@ -908,6 +909,7 @@ static void riscv_tr_init_disas_context(DisasContextBase 
*dcbase, CPUState *cs)
 #endif
     ctx->misa_ext = env->misa_ext;
     ctx->frm = -1;  /* unknown rounding mode */
+    ctx->cfg_ptr = &(cpu->cfg);
     ctx->ext_ifencei = cpu->cfg.ext_ifencei;
     ctx->ext_zfh = cpu->cfg.ext_zfh;
     ctx->ext_zfhmin = cpu->cfg.ext_zfhmin;
-- 
2.33.1