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From "xiaoming gu" <xiaoming...@gmail.com>
Subject Re: a quick question for signed shift right for long type
Date Thu, 10 Jul 2008 12:45:09 GMT
With H5901-V2.patch, A/16=-5 if A=-70 and A is a long. After checking each
step, I found the mask
for a>>63 is not right, which should be 0xffffffffffffffff but is
0xffffffff00000001. I tried many ways but couldn't
find the reason. Thanks for your help.

Xiaoming

On Thu, Jul 10, 2008 at 5:53 PM, Aleksey Shipilev <
aleksey.shipilev@gmail.com> wrote:

> Hi, Xiaoming!
>
> Can you provide the exact test case?
> It's not obvious what do you try to say.
>
> Thanks,
> Aleksey.
>
> On Thu, Jul 10, 2008 at 1:36 PM, xiaoming gu <xiaoming.gu@gmail.com>
> wrote:
> > Hi, all. I just got a problem with signed shift right problem.
> >
> > long a = 0x8000000000000000;
> > long b = a>>63; // b is 0xffffffffffffffff
> >
> > But if I use SAR to do the signed shift right in harmony internally, b is
> > 0xffffffff00000001.
> > I traced the code for a while and couldn't find the difference for the
> two
> > ways.
> >
> > Any idea? Thanks.
> >
> > Xiaoming
> >
>

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