[llvm] [DebugInfo][DWARF] Add heapallocsite information (PR #132073)

[Andrew Pinski via llvm-commits]

pinskia wrote:

> @pinskia I'm not familiar with how DWARF standard development works in practice - do you mean just propose it for the DWARF standard, then add it to LLVM as an LLVM extension in parallel while the DWARF committee figures out whether they want to standardize it? Or actually land it in the (working draft? official?) DWARF standard before adding the feature to LLVM at all?

First start with https://dwarfstd.org/procedures.html .
Second having a full written up proposal of the extension is useful NOT just for the dwarf standard but also for others to consume/emit the extension and not just based on the code in LLVM. For me having a decent written up proposal shoud be enough for adding the feature to any emittor/consumer. I don't know how this was handled before in LLVM but since this will be consumed by more than LLVM/LLDB, having a proposal at least documenting the extension more than just a number should be a good thing to do anyways.

https://github.com/llvm/llvm-project/pull/132073