This is the mail archive of the binutils@sourceware.org mailing list for the binutils project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [PATCH] x86: Determine vector length from the last vector operand


>>> On 24.07.18 at 18:52, <hjl.tools@gmail.com> wrote:
> On Tue, Jul 24, 2018 at 6:57 AM, H.J. Lu <hjl.tools@gmail.com> wrote:
>> On Tue, Jul 24, 2018 at 6:50 AM, Jan Beulich <JBeulich@suse.com> wrote:
>>>>>> On 24.07.18 at 15:43, <hjl.tools@gmail.com> wrote:
>>>> I don't see there are significant differences here.
>>>> It is perfectly OK to use "int" as index.
>>>
>>> Generated code is worse on many architectures: Often sub-machine-
>>> word size loads (and on x86-64 also other operations) are zero-
>>> extending. A signed index hence needs sign-extending in a separate
>>> step, rather than being able to directly use the result of the load (or
>>> other operation).
>>>
>>
>> Sure.  Go ahead if you want to change it to unsigned.
>>
> 
> This is what I checked in.

Thanks much!

Jan



Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]