- Add AMDGPU DWARF proposal.
- Add references for gfx10 ISA and SemVer.
Add DW_OP_LLVM_call_frame_entry_reg and fix typos
- Add DW_OP_LLVM_call_frame_entry_reg needed for CFI unwinding of VGPRs that are spilled using the EXEC mask on entry.
- Remove mention of DW_OP_* that are no longer part of the proposal.
- Correct some names and other minor typos.
I think this is at a stage where it is OK to commit it to AMDGPUUsage as a draft proposal, to let us iterate on it before actually proposing it to DWARF proper. It is harder to start a discussion about it without a public document describing it, and it seems easier to refer to it in AMDGPUUsage than to refer to a Phabricator review.