[cfe-commits] [PATCH] struct{bool} -> int function argument coercion emits an invalid store on ARM

[Evgeniy Stepanov]

Please consider the new patch.
This time, if the coerce-to type is larger than the real type, we
reconstruct a value of the coerce-to type in a stack allocation, then
bitcast & copy it into the destination.
This is roughly the same logic as in CreateCoercedStore, but with
multiple sources.

On Sat, Feb 4, 2012 at 6:12 PM, Evgeniy Stepanov
<eugeni.stepanov at gmail.com> wrote:
> On Sat, Feb 4, 2012 at 1:07 AM, Eli Friedman <eli.friedman at gmail.com> wrote:
>> On Fri, Feb 3, 2012 at 4:05 AM, Evgeniy Stepanov
>> <eugeni.stepanov at gmail.com> wrote:
>>> Hi,
>>>
>>> this is a fix for PR11905.
>>>
>>> The current behaviour when generation a function prolog for arguments
>>> of coerced types is to allocate a stack temp of the real argument type
>>> and store the argument(s) there. This is wrong, because storage size
>>> of the coerce-to type can be larger than that of the real type.
>>>
>>> The new behaviour is to allocate a temp of the coerced type, copy it,
>>> and then reference through a bitcasted pointer of the real type.
>>>
>>> Please review.
>>
>> The real type is sometimes larger than the coerced type... switching
>> from one to the other only changes which cases are broken issues.
>
> Could you give an example of that?
> In that case, what would you think of allocating the largest of the two types?
>
>>
>> -Eli
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