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Re: [Qemu-devel] [PATCH v2] target/arm: Vectorize USHL and SSHL
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From: |
Richard Henderson |
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Subject: |
Re: [Qemu-devel] [PATCH v2] target/arm: Vectorize USHL and SSHL |
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Date: |
Fri, 7 Jun 2019 10:40:48 -0500 |
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User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 |
On 6/7/19 9:54 AM, Peter Maydell wrote:
> On Tue, 4 Jun 2019 at 00:22, Richard Henderson
> <address@hidden> wrote:
>>
>> These instructions shift left or right depending on the sign
>> of the input, and 7 bits are significant to the shift. This
>> requires several masks and selects in addition to the actual
>> shifts to form the complete answer.
>>
>> That said, the operation is still a small improvement even for
>> two 64-bit elements -- 13 vector operations instead of 2 * 7
>> integer operations.
>>
>> Signed-off-by: Richard Henderson <address@hidden>
>> ---
>
> Applied to target-arm.next, thanks.
>
> NB: in v1 this series had a second patch. I'm assuming you
> dropped it deliberately -- if not, let me know.
Oops, no. Can you please grab it with your r-b from v1?
r~