Re: [PATCH v3 20/27] disas/microblaze: Split get_field_special

[Pierrick Bouvier <pierrick.bouvier@linaro.org>]

On 4/12/24 00:33, Richard Henderson wrote:
> Extract the raw special index and a function to lookup a name.
> 
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>   disas/microblaze.c | 142 +++++++++++++++++++--------------------------
>   1 file changed, 61 insertions(+), 81 deletions(-)
> 
> diff --git a/disas/microblaze.c b/disas/microblaze.c
> index 24febfdea9..197327fae4 100644
> --- a/disas/microblaze.c
> +++ b/disas/microblaze.c
> @@ -564,8 +564,6 @@ static const struct op_code_struct {
>   
>   /* prefix for register names */
>   #define register_prefix "r"
> -static const char pvr_register_prefix[] = "rpvr";
> -
>   
>   /* #defines for valid immediate range */
>   #define MIN_IMM  ((int) 0x80000000)
> @@ -580,6 +578,7 @@ static const char pvr_register_prefix[] = "rpvr";
>   
>   #define PRIreg    register_prefix "%ld"
>   #define PRIrfsl   register_prefix "fsl%ld"
> +#define PRIpvr    register_prefix "pvr%d"
>   #define PRIimm    "%d"
>   
>   #define get_field_rd(instr)      ((instr & RD_MASK) >> RD_LOW)
> @@ -593,83 +592,48 @@ static const char pvr_register_prefix[] = "rpvr";
>   #define get_int_field_imm(instr) ((instr & IMM_MASK) >> IMM_LOW)
>   #define get_int_field_r1(instr) ((instr & RA_MASK) >> RA_LOW)
>   
> -/*
> -  char *
> -  get_field_special (instr)
> -  long instr;
> -  {
> -  char tmpstr[25];
> -
> -  snprintf(tmpstr, sizeof(tmpstr), "%s%s", register_prefix,
> -          (((instr & IMM_MASK) >> IMM_LOW) & REG_MSR_MASK) == 0 ? "pc" : "msr");
> -
> -  return(strdup(tmpstr));
> -  }
> -*/
> -
> -static char *
> -get_field_special(long instr, const struct op_code_struct *op)
> +static int get_field_special(long instr, const struct op_code_struct *op)
>   {
> -   char tmpstr[25];
> -   char spr[6];
> +    return ((instr & IMM_MASK) >> IMM_LOW) ^ op->immval_mask;
> +}
>   
> -   switch ( (((instr & IMM_MASK) >> IMM_LOW) ^ op->immval_mask) ) {
> -
> -   case REG_MSR_MASK :
> -      strcpy(spr, "msr");
> -      break;
> -   case REG_PC_MASK :
> -      strcpy(spr, "pc");
> -      break;
> -   case REG_EAR_MASK :
> -      strcpy(spr, "ear");
> -      break;
> -   case REG_ESR_MASK :
> -      strcpy(spr, "esr");
> -      break;
> -   case REG_FSR_MASK :
> -      strcpy(spr, "fsr");
> -      break;
> -   case REG_BTR_MASK :
> -      strcpy(spr, "btr");
> -      break;
> -   case REG_EDR_MASK :
> -      strcpy(spr, "edr");
> -      break;
> -   case REG_PID_MASK :
> -      strcpy(spr, "pid");
> -      break;
> -   case REG_ZPR_MASK :
> -      strcpy(spr, "zpr");
> -      break;
> -   case REG_TLBX_MASK :
> -      strcpy(spr, "tlbx");
> -      break;
> -   case REG_TLBLO_MASK :
> -      strcpy(spr, "tlblo");
> -      break;
> -   case REG_TLBHI_MASK :
> -      strcpy(spr, "tlbhi");
> -      break;
> -   case REG_TLBSX_MASK :
> -      strcpy(spr, "tlbsx");
> -      break;
> -   default :
> -     {
> -       if ( ((((instr & IMM_MASK) >> IMM_LOW) ^ op->immval_mask) & 0xE000) == REG_PVR_MASK) {
> -          snprintf(tmpstr, sizeof(tmpstr), "%s%u", pvr_register_prefix,
> -                 (unsigned short)(((instr & IMM_MASK) >> IMM_LOW) ^
> -                                  op->immval_mask) ^ REG_PVR_MASK);
> -	 return(strdup(tmpstr));
> -       } else {
> -	 strcpy(spr, "pc");
> -       }
> -     }
> -     break;
> -   }
> -
> -   snprintf(tmpstr, sizeof(tmpstr), "%s%s", register_prefix, spr);
> -   return(strdup(tmpstr));
> +/* Returns NULL for PVR registers, which should be rendered differently. */
> +static const char *get_special_name(int special)
> +{
> +    switch (special) {
> +    case REG_MSR_MASK:
> +        return register_prefix "msr";
> +    case REG_PC_MASK:
> +        return register_prefix "pc";
> +    case REG_EAR_MASK:
> +        return register_prefix "ear";
> +    case REG_ESR_MASK:
> +        return register_prefix "esr";
> +    case REG_FSR_MASK:
> +        return register_prefix "fsr";
> +    case REG_BTR_MASK:
> +        return register_prefix "btr";
> +    case REG_EDR_MASK:
> +        return register_prefix "edr";
> +    case REG_PID_MASK:
> +        return register_prefix "pid";
> +    case REG_ZPR_MASK:
> +        return register_prefix "zpr";
> +    case REG_TLBX_MASK:
> +        return register_prefix "tlbx";
> +    case REG_TLBLO_MASK:
> +        return register_prefix "tlblo";
> +    case REG_TLBHI_MASK:
> +        return register_prefix "tlbhi";
> +    case REG_TLBSX_MASK:
> +        return register_prefix "tlbsx";
> +    default:
> +        if ((special & 0xE000) == REG_PVR_MASK) {
> +            /* pvr register */
> +            return NULL;
> +        }
> +        return register_prefix "pc";
> +    }
>   }
>   
>   static unsigned long
> @@ -739,6 +703,8 @@ print_insn_microblaze(bfd_vma memaddr, struct disassemble_info *info)
>       static bfd_vma prev_insn_addr = -1; /*init the prev insn addr */
>       static int prev_insn_vma = -1;  /*init the prev insn vma */
>       int curr_insn_vma = info->buffer_vma;
> +    int special;
> +    const char *special_name;
>   
>       info->bytes_per_chunk = 4;
>   
> @@ -799,12 +765,26 @@ print_insn_microblaze(bfd_vma memaddr, struct disassemble_info *info)
>                        op->name, get_field_r1(inst), get_field_rfsl(inst));
>           break;
>       case INST_TYPE_RD_SPECIAL:
> -        fprintf_func(stream, "%s\t" PRIreg ", %s",
> -                     op->name, get_field_rd(inst), get_field_special(inst, op));
> +        special = get_field_special(inst, op);
> +        special_name = get_special_name(special);
> +        if (special_name) {
> +            fprintf_func(stream, "%s\t" PRIreg ", %s",
> +                         op->name, get_field_rd(inst), special_name);
> +        } else {
> +            fprintf_func(stream, "%s\t" PRIreg ", " PRIpvr,
> +                         op->name, get_field_rd(inst), special ^ REG_PVR_MASK);
> +        }
>           break;
>       case INST_TYPE_SPECIAL_R1:
> -        fprintf_func(stream, "%s\t%s, " PRIreg,
> -                     op->name, get_field_special(inst, op), get_field_r1(inst));
> +        special = get_field_special(inst, op);
> +        special_name = get_special_name(special);
> +        if (special_name) {
> +            fprintf_func(stream, "%s\t%s, " PRIreg,
> +                         op->name, special_name, get_field_r1(inst));
> +        } else {
> +            fprintf_func(stream, "%s\t" PRIpvr ", " PRIreg,
> +                         op->name, special ^ REG_PVR_MASK, get_field_r1(inst));
> +        }
>           break;
>       case INST_TYPE_RD_R1:
>           fprintf_func(stream, "%s\t" PRIreg ", " PRIreg,

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>