llvm dev - Jul 2017 - AsmPrinter.cpp: emitting trailing padding for global data array in emitGlobalConstantDataSequential

Hello all,

Looking at the emitGlobalConstantDataSequential function in
lib/CodeGen/AsmPrinter/AsmPrinter.cpp  there is a code there responsible
for emitting of the potential trailing padding for the global array.

Is there an example ( preferably C code ) that triggers this code?  AFAIU
no trailing padding should be generated for global data arrays.

Thanks
Vlad
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On 7/31/2017 4:20 PM, Vlad Dov vdovleka via llvm-dev
wrote:
> Hello all,
>
> Looking at the emitGlobalConstantDataSequential function in 
> lib/CodeGen/AsmPrinter/AsmPrinter.cpp  there is a code there 
> responsible for emitting of the potential trailing padding for the 
> global array.
>
> Is there an example ( preferably C code ) that triggers this code?  
> AFAIU no trailing padding should be generated for global data arrays.
You're right, no trailing padding will be generated for arrays: the 
alignment of an array is the same as the alignment of its element type.  
We can end up with trailing padding for vectors, though.  For example:

typedef float float3 __attribute((ext_vector_type(3)));
float3 x = {1,2,3};

-Eli

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