Re: [PATCH v2 4/6] linux-user/elfload: Introduce MIPS GET_FEATURE_REG_EQU() macro

[Richard Henderson]

On 12/1/20 7:35 AM, Philippe Mathieu-Daudé wrote:
> +#define GET_FEATURE_REG_EQU(_reg, _mask, _val, _hwcap) \
> +    do { \
> +        if ((cpu->env._reg & (_mask)) == _val) { \
> +            hwcaps |= _hwcap; \
> +        } \
> +    } while (0)
> +
>  static uint32_t get_elf_hwcap(void)
>  {
>      MIPSCPU *cpu = MIPS_CPU(thread_cpu);
>      uint32_t hwcaps = 0;
>  
> -    GET_FEATURE_INSN(ISA_MIPS32R6 | ISA_MIPS64R6, HWCAP_MIPS_R6);
> +    GET_FEATURE_REG_EQU(CP0_Config0, 7 << CP0C0_AR, 2, HWCAP_MIPS_R6);

You'd need 2 << CP0C0_AR for the equality to match.
Would it be better to have the shift as a separate argument?


r~