llvm dev - Apr 2014 - [LLVMdev] LowerFormalArguments: info on aggregates

Hi,

All arguments processed in the function LowerFormalArguments seem to be 
are already lowered to machine types. In addition, the flag isByVal 
seems to be set for each argument passed on the stack, and cannot be 
used to indicate a struct/union.

Is there a way to tell if an argument is of a simple type or of an 
aggregate (within LowerFormalArguments)? Is there any better way 
processing stack alignment of incoming arguments? This information would 
be needed for correct stack alignment of structs vs. simple types in 
AArch64 big endian mode.

Thanks,
Conny

On Apr 16, 2014, at 3:50 AM, Konrad Anheim <kanheim at a-bix.com> wrote:
> Hi,
> 
> All arguments processed in the function LowerFormalArguments seem to be are
already lowered to machine types. In addition, the flag isByVal seems to be set
for each argument passed on the stack, and cannot be used to indicate a
struct/union.
> 
> Is there a way to tell if an argument is of a simple type or of an
aggregate (within LowerFormalArguments)? Is there any better way processing
stack alignment of incoming arguments? This information would be needed for
correct stack alignment of structs vs. simple types in AArch64 big endian mode.
‘
If you check the ISD::InputArg, ArgVT should tell you the original type. If you
look at R600 , it has a function that uses this to find all of the original
argument types.

-Matt