[clang] [AIX] recognize vsr in inline asm for AIX (PR #68476)

[Chen Zheng via cfe-commits]

================
@@ -807,7 +807,7 @@ ArrayRef<TargetInfo::GCCRegAlias> PPCTargetInfo::getGCCRegAliases() const {
 // PPC ELFABIv2 DWARF Definitoin "Table 2.26. Mappings of Common Registers".
 // vs0 ~ vs31 is mapping to 32 - 63,
 // vs32 ~ vs63 is mapping to 77 - 108.
----------------
chenzheng1030 wrote:

This is what I get from DWARF spec:

Note that the register number represents a DWARF specific mapping of numbers onto the actual registers of a given architecture. The mapping should be chosen to gain optimal density and should be shared by all users of a given architecture. It is recommended that this mapping be defined by the ABI authoring committee for each architecture.

To me, the DWARF number should be architecture specific, i.e., although the ABIs are different, all these ABIs on same architecture should use same DWARF register mapping, because the hardware registers are bound to architecture?

https://github.com/llvm/llvm-project/pull/68476