On Wed, 20 May 2026 16:24:59 GMT, Aleksey Shipilev <[email protected]> wrote:
>> Ferenc Rakoczi has updated the pull request incrementally with one
>> additional commit since the last revision:
>>
>> Accepting more suggestions from Andrew Dinn.
>
> src/hotspot/cpu/aarch64/assembler_aarch64.hpp line 3166:
>
>> 3164: assert(Ts == H ? Vm->encoding() < 16 : Vm->encoding() < 32,
>> "umull{2}v requires Vm to be in range V0..V15 when Ts is H");
>> 3165: f(0, 31), f(q, 30), f(0b101111, 29, 24), f(size, 23, 22), f(l,
>> 21); //f(m, 20);
>> 3166: rf(Vm, 16), f(0b1010, 15, 12), f(h, 11), f(0, 10), rf(Vn, 5),
>> rf(Vd, 0);
>
> Why `f(m, 20)` is commented here? Does it need to be set?
It doesn't. AArch64 assembler throws an assertion if any field of an
instruction is not set. I think it's because `Vm` may have to be <15, so that
bi twill be clear. But the comment is more confusing than helpful.
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PR Review Comment: https://git.openjdk.org/jdk/pull/30941#discussion_r3279709250
