domada added inline comments.

================
Comment at: llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp:2976
 
+  const int DefaultAlignment = 16;
+
----------------
jdoerfert wrote:
> domada wrote:
> > jdoerfert wrote:
> > > This doesn't work. Use the data layout for any default values please.
> > I have used pointer ABI alignment as the default value. Is it ok?
> > Clang has separate method to calculate OpenMP default alignment defined in 
> > TargetInfo class ( [[ 
> > https://clang.llvm.org/doxygen/classclang_1_1TargetInfo.html#af0c75e3288adc13601732329c44db147
> >  |  link ]])
> > Unfortunately, there is no simple replacement of this function in 
> > OMPIRBuilder or in Flang driver. There are some requests to expose 
> > TargetInfo data in Clang-independent manner: [[ 
> > https://discourse.llvm.org/t/rfc-targetinfo-library/64342 | RFC1 ]], 
> > [[https://discourse.llvm.org/t/complex-to-libm-conversion-abi-issues/65131 
> > |RFC2]] , but this issue is not solved.
> Let's step back:
> 1) User tells us the alignment via `aligned(X:64)`. This should populate the 
> map in Clang, I would assume.
> 2) User tells us the alignment "implicitly" via `align(Y)`. Again, clang 
> should populate the map with the default/preferred alignment of the type. You 
> can use the function you linked, or use the data layout API to get the 
> preferred alignment.
> 3) User tells us nothing. We should pick the default or, don't annotate 
> anything. If we go with defaults, you need to look up the default for the 
> address space but I don't know why we would annotate anything not provided by 
> the user.
> 
> 
Ad 1) Agree
Ad 2) OK, I will add assertion to ensure that the map is correctly populated 
with the default/preferred alignment if the user specifies only: `align(Y)`.

I was thinking that OMPIRBuilder should pick the default value if the user 
specifies `align(Y)`. Thanks for clarification. 

Ad 3)  I assume that if the user tells us nothing we should not annotate 
anything. I will expect empty map and no generated annotations. Currently we do 
not generate any annotations if there is no align clause.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D133578/new/

https://reviews.llvm.org/D133578

_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits

Reply via email to