[cfe-dev] Windows PDATA/XDATA for Clang Inline Assembly

[Martin Storsjö via cfe-dev]

On Fri, 16 Oct 2020, Hayden Livingston via cfe-dev wrote:

> Thank you, Reid for this reply and all the work you (and others) do to
> help Windows users of LLVM/Clang.
>
> And this works for ARM64 as well?
> https://lists.llvm.org/pipermail/llvm-dev/2018-July/124727.html which
> is a couple of years old but you ask someone to see if they would add
> support I don't know if that ever made it.

General support for unwind info code generation was added back then, and 
was mostly complete around LLVM 8.

But support for generating unwind info in assembly (both inline and 
external) wasn't added back then; that was added recently in the master 
branch though. See e.g. 
https://github.com/llvm/llvm-project/commit/5b86d130e2baed7221b09087c506f5974fe65f22#diff-2aa6bd21d4d021458b63376b56c919f9638fc172e1dfe2170d5d4653cde431a5 
and 
https://github.com/llvm/llvm-project/commit/f5e2ea9a43221be9576056c4912796cf37331cd7#diff-2aa6bd21d4d021458b63376b56c919f9638fc172e1dfe2170d5d4653cde431a5 
for examples on the syntax. As the instruction set and unwind opcodes 
differ between x86_64 and arm64, the assembly directives also differ 
accordingly.

// Martin