[LLVMdev] alignment issue, getting corrupt double values

[edA-qa mort-ora-y]

I can confirm that if I generate the value directly (not via a return)
then the expected values are extracted from the structure. So it is
perhaps a return value issue.

On 30/12/12 19:04, Peng Cheng wrote:
> I also saw this issue before.  Llvm seems have trouble returning general
> struct values from functions.  One easy workaround is to use packed
> struct type.
> 
> Hope this helps.
> 
> -Peng
> 
> On Sunday, December 30, 2012, edA-qa mort-ora-y wrote:
> 
>     I'm having an issue where a certain set of types and insert/extractvalue
>     are producing the incorrect values. It appears as though extractvalue
>     getting my sub-structure is not getting the correct data.
> 
>     I have these types:
> 
>     %outer = type { i32, %inner, i1 }
>     %inner = type { double, i32 }
> 
>     The trouble is that when I have a value of type %outer then proceed to
>     extract the components of the contained %inner structure I get corrupt
>     values. If I don't have the "i1" type in there everything works fine,
>     leading me to think it is something to do with alignment. I do the
>     extraction with code like this:
> 
>             %o = call %outer @eval_expr()
>             %s = extractvalue %outer %o, 1
>             %s1 = extractvalue %inner %s, 0
> 
>     The %s1 value is not correct (not what was inserted). I think extraction
>     is the problem and not insertion: in another version I store the value
>     to a global variable and dump the bytes of the structure, which can then
>     be properly extracted in C++ code.  The value is produced with this code
>     (in a separate function):
> 
>             %s0 = insertvalue %inner undef, double 1.500000e+00, 0
>             %s1 = insertvalue %inner %s0, i32 2, 1
>             %s2 = insertvalue %outer undef, i32 1, 0
>             %s3 = insertvalue %outer %s2, %inner %s1, 1
> 
> 
>     I've attached the full sample code which shows the error and where it
>     happens.
> 
>     --
>     edA-qa mort-ora-y
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edA-qa mort-ora-y
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