Re: [Qemu-devel] [PATCH v2 12/15] target-mips: microMIPS32 R6 POOL32{I, C} instructions

[Leon Alrae]

On 19/06/2015 17:25, Yongbok Kim wrote:
> add new microMIPS32 Release 6 POOL32I/POOL32C type instructions
> 
> Signed-off-by: Yongbok Kim <address@hidden>
> ---
>  target-mips/translate.c |   31 +++++++++++++++++++++++++------
>  1 files changed, 25 insertions(+), 6 deletions(-)
> 
> diff --git a/target-mips/translate.c b/target-mips/translate.c
> index 5f6ae43..54c14b6 100644
> --- a/target-mips/translate.c
> +++ b/target-mips/translate.c
> @@ -14652,9 +14652,18 @@ static void decode_micromips32_opc(CPUMIPSState 
> *env, DisasContext *ctx)
>              check_insn_opc_removed(ctx, ISA_MIPS32R6);
>              mips32_op = OPC_TGEIU;
>              goto do_trapi;
> -        case TNEI:
> -            mips32_op = OPC_TNEI;
> -            goto do_trapi;
> +        case TNEI: /* SYNCI */
> +            if (ctx->insn_flags & ISA_MIPS32R6) {
> +                /* SYNCI */
> +                /* Break the TB to be able to sync copied instructions
> +                   immediately */
> +                ctx->bstate = BS_STOP;
> +            } else {
> +                /* TNEI */
> +                mips32_op = OPC_TNEI;
> +                goto do_trapi;
> +            }
> +            break;
>          case TEQI:
>              check_insn_opc_removed(ctx, ISA_MIPS32R6);
>              mips32_op = OPC_TEQI;
> @@ -14784,23 +14793,33 @@ static void decode_micromips32_opc(CPUMIPSState 
> *env, DisasContext *ctx)
>              mips32_op = OPC_LL;
>              goto do_ld_lr;
>          do_ld_lr:
> -            gen_ld(ctx, mips32_op, rt, rs, SIMM(ctx->opcode, 0, 12));
> +            offset = sextract32(ctx->opcode, 0,
> +                                (ctx->insn_flags & ISA_MIPS32R6) ? 9 : 12);
> +            gen_ld(ctx, mips32_op, rt, rs, offset);
>              break;
>          do_st_lr:
>              gen_st(ctx, mips32_op, rt, rs, SIMM(ctx->opcode, 0, 12));
>              break;
>          case SC:
> -            gen_st_cond(ctx, OPC_SC, rt, rs, SIMM(ctx->opcode, 0, 12));
> +            offset = sextract32(ctx->opcode, 0,
> +                                (ctx->insn_flags & ISA_MIPS32R6) ? 9 : 12);
> +            gen_st_cond(ctx, OPC_SC, rt, rs, offset);
>              break;
>  #if defined(TARGET_MIPS64)
>          case SCD:
>              check_insn(ctx, ISA_MIPS3);
>              check_mips_64(ctx);
> -            gen_st_cond(ctx, OPC_SCD, rt, rs, SIMM(ctx->opcode, 0, 12));
> +            offset = sextract32(ctx->opcode, 0,
> +                                (ctx->insn_flags & ISA_MIPS32R6) ? 9 : 12);

What I meant earlier was offset calculated at the beginning of case POOL32C
just once for the whole family of these instructions rather than individually.

Thanks,
Leon

> +            gen_st_cond(ctx, OPC_SCD, rt, rs, offset);
>              break;
>  #endif
>          case PREF:
>              /* Treat as no-op */
> +            if ((ctx->insn_flags & ISA_MIPS32R6) && (rt >= 24)) {
> +                /* hint codes 24-31 are reserved and signal RI */
> +                generate_exception(ctx, EXCP_RI);
> +            }
>              break;
>          default:
>              MIPS_INVAL("pool32c");
>