>
> Yes in big-endian DI mode value are stored into VFP registers, and
> here register 16 is the first of them s0. Just in case you want to do
> more test, the issue can be seen with a oneline testcase:
>
> __attribute__((__vector_size__(2 * sizeof(int)))) int fn1() {}
Yep we may well have DImode values in the VFP register bank.
>
>> I observe that FIRST_VIRTUAL_REGISTER is 104, whereas LAST_ARM_REG is 15. So
>> it might be that the pattern should check against the latter instead of the
>> former - as arm_hard_regno_mode_ok does...
>
> yes, when checking that that the operand register number is lower or
> equals to LAST_ARM_REGNUM the infinite loop is avoided. I haven't
> pass a full validation so far, but it has the same effect than
> checking that the changing mode is authorized. If you think that this
> checking makes more sense, I can rerun a full valid.
It sounds to me like checking against LAST_ARM_REGNUM is the better approach.
The additional test in the movdi expander was to prevent illegitimate ldrd /
strd instructions from being generated.
Thus, OK if there are no regressions - Please give it some time to bake on
trunk before backporting to FSF 5 and / or do some additional validation
(including the regression testsuite) before doing the backport.
regards
Ramana
>
> Thanks,
> Yvan
>
>
> yes
>
>
>> --Alan
>>
