Re: [Qemu-devel] [RFC 23/48] translator: add plugin_insn argument to translate_insn

[Emilio G. Cota]

On Wed, Nov 28, 2018 at 12:40:23 +0000, Alex Bennée wrote:
> I was envisioning something more like the following so all the plugin
> gubins could be kept in the core code:
(snip)
>  static inline uint32_t arm_ldl_code(CPUARMState *env, target_ulong addr,
>                                      bool sctlr_b)
>  {
> -    uint32_t insn = cpu_ldl_code(env, addr);
> -    if (bswap_code(sctlr_b)) {
> -        return bswap32(insn);
> -    }
> -    return insn;
> +    return translator_ld32(env, addr, bswap_code(sctlr_b));
>  }
> 
>  /* Ditto, for a halfword (Thumb) instruction */
>  static inline uint16_t arm_lduw_code(CPUARMState *env, target_ulong addr,
>                                       bool sctlr_b)
>  {
> -    uint16_t insn;
>  #ifndef CONFIG_USER_ONLY
>      /* In big-endian (BE32) mode, adjacent Thumb instructions have been 
> swapped
>         within each word.  Undo that now.  */
> @@ -46,11 +40,7 @@ static inline uint16_t arm_lduw_code(CPUARMState *env, 
> target_ulong addr,
>          addr ^= 2;
>      }
>  #endif
> -    insn = cpu_lduw_code(env, addr);
> -    if (bswap_code(sctlr_b)) {
> -        return bswap16(insn);
> -    }
> -    return insn;
> +    return translator_ld16(env, addr, bswap_code(sctlr_b));
>  }

I like this, thanks.

However, for Thumb I think we still need to call qemu_plugin_insn_append
directly:

@@ -13304,11 +13306,16 @@ static void thumb_tr_translate_insn(DisasContextBase 
*dcbase, CPUState *cpu)
     insn = arm_lduw_code(env, dc->pc, dc->sctlr_b);
     is_16bit = thumb_insn_is_16bit(dc, insn);
     dc->pc += 2;
-    if (!is_16bit) {
+    if (is_16bit) {
+        uint16_t insn16 = insn;
+
+        qemu_plugin_insn_append(tcg_ctx->plugin_insn, &insn16, sizeof(insn16));
+    } else {
         uint32_t insn2 = arm_lduw_code(env, dc->pc, dc->sctlr_b);

         insn = insn << 16 | insn2;
         dc->pc += 2;
+        qemu_plugin_insn_append(tcg_ctx->plugin_insn, &insn, sizeof(insn));
     }
 
Otherwise we might mess up the contents of 32-bit insns.

Thanks,

                E.