On 29 August 2017 at 17:08, Richard Henderson
<richard.hender...@linaro.org> wrote:
> On 08/22/2017 08:08 AM, Peter Maydell wrote:
>> + if (attrs.secure) {
>> + /* the BFHFNMIGN bit is not banked; keep that in the NS copy */
>> + int new_bfhnmign = !!(value & R_V7M_CCR_BFHFNMIGN_MASK);
>> +
>> + cpu->env.v7m.ccr[M_REG_NS] =
>> deposit32(cpu->env.v7m.ccr[M_REG_NS],
>> +
>> R_V7M_CCR_BFHFNMIGN_SHIFT,
>> +
>> R_V7M_CCR_BFHFNMIGN_LENGTH,
>> + new_bfhnmign);
>> + value &= ~R_V7M_CCR_BFHFNMIGN_MASK;
>> + }
>
> No need to extract and then redeposit, just use the mask.
>
> cpu->env.v7m.ccr[M_REG_NS] =
> (cpu->env.v7m.ccr[M_REG_NS] & ~R_V7M_CCR_BFHFNMIGN_MASK)
> | (value & R_V7M_CCR_BFHFNMIGN_MASK);
Mmm. This is one of the operations that deposit/extract aren't
too wonderful for. I don't generally like direct messing with
bit operations, I think they're harder to read, but there's not
much in it here so I'll go with your version.
thanks
-- PMM
