[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:

> 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?

While that makes sense, I am not seeing elsewhere in the code comments that the DWARF numbers are being used. The code _does_ support (in `getNormalizedGCCRegisterName`) that these numbers are used to index into the `GCCRegNames` array.

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