release_33 branch: proposing r183297

[David Blaikie]

On Mon, Jul 8, 2013 at 1:04 PM, Eric Christopher <echristo at gmail.com> wrote:
> I'm fine with merging this change, though I don't think it was in
> isolation. Dave should be able to comment on any dependencies.

It's been a while (mentally, if not on the calendar) since I made this
change & don't remember precisely. If Dimitry's applied this to the
3.3 release branch & it passes the associated tests & his own
tests/needs, that sounds like reasonable due diligence.

- Dave

>
> -eric
>
> On Mon, Jul 8, 2013 at 12:55 PM, Dimitry Andric <dimitry at andric.com> wrote:
>> Hi,
>>
>> For the 3.3 release branch, I would like to propose merging r183297:
>>
>> r183297 from llvm trunk (by David Blaikie):
>>
>>   PR15662: Optimized debug info produces out of order function
>>   parameters
>>
>>   When a function is inlined we lazily construct the variables
>>   representing the function's parameters. After that, we add any
>>   remaining unused parameters.
>>
>>   If the function doesn't use all the parameters, or uses them out of
>>   order, then the DWARF would produce them in that order, producing a
>>   parameter order that doesn't match the source.
>>
>>   This fix causes us to always keep the arg variables at the start of
>>   the variable list & in the original order from the source.
>>
>> On FreeBSD, this enables DTrace to work properly on certain functions compiled with optimization, where previously the debug information had its arguments swapped around.
>>
>> This commit should apply to the release_33 branch without modification.
>>
>> -Dimitry
>>