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

[Hubert Tong via cfe-commits]

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@@ -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.
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hubert-reinterpretcast wrote:

I am not sure it helps to appeal to the ELFABIv2 DWARF definition if we are no longer restraining this data to be used only under ELFABIv2. Instead, the usage here can be explained as the index numbers for the related FPRs and VRs in `GCCRegNames` above.

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