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Re: predicate aware uninitialized variable analysis
On 10/12/2010 02:26 AM, Richard Guenther wrote:
> On Mon, 11 Oct 2010, Xinliang David Li wrote:
>
>> On Mon, Oct 11, 2010 at 11:14 PM, Andrew Pinski <pinskia@gmail.com> wrote:
>>> On Wed, Apr 14, 2010 at 5:44 PM, Richard Guenther
>>> <richard.guenther@gmail.com> wrote:
>>>> Can you instead of returning a sbitmap from compute_uninit_opnds_pos
>>>> use an unsigned int mask (with proper checks for PHIs with too many
>>>> operands which you don't want to handle because of complexity
>>>> reasons anyway)?
>>>
>>> Looks the proper checks for PHIs with too many operands which you
>>> don't want to handle was never done. And the current proposal on the
>>> table to fix that does not skip them but rather just truncates them.
>>
>> To make it stable across hosts, I can change it back to use unsigned
>> and do the skipping as originally suggested. I will wait a little
>> longer for more comments (Richard) before making that change just in
>> case -- in particular which one is more preferred: using wider type
>> vs. consistency across hosts.
>
> Well, you can simply use unsigned HOST_WIDEST_FAST_INT and skip for
> more than 32 PHI arguments (HOST_WIDEST_FAST_INT is at least 4 bytes
> on all supported hosts).
Yes, but if you're going to skip for 32, you might as well use
"unsigned", which is also at least 4 bytes on supported hosts.
r~