[llvm-commits] [llvm] r66366 - in /llvm/trunk: lib/Transforms/Scalar/ScalarReplAggregates.cpp test/Transforms/ScalarRepl/2008-06-22-LargeArray.ll test/Transforms/ScalarRepl/vector_memcpy.ll

[Chris Lattner]

On Mar 8, 2009, at 12:52 PM, Duncan Sands wrote:
>>>> This is converting a memcpy to a load/store of the same size, so it
>>>> must be a multiple of a byte in size.
>>>
>>> How is the size measured?  By getTypeSizeInBits,
>>> getTypeStoreSizeInBits
>>> or getTypePaddedSizeInBits?  The first one is ok, the others not.
>>
>> Padded Size.  Why do you think it isn't safe?  Have an example?
>
> Sure, consider an i24.  The padded size is 32 bits.  A memcpy will
> copy 32 bits, a load/store will copy 24 bits.

This xform would turn it into an i32, not an i24.

-Chris