[llvm] [PowerPC] Add DMR and WACC COPY support (PR #149129)

[Lei Huang via llvm-commits]

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@@ -122,6 +122,33 @@ namespace {
           // Transform the original copy into a subregister extraction copy.
           SrcMO.setReg(NewVReg);
           SrcMO.setSubReg(PPC::sub_64);
+        } else if (IsRegInClass(DstMO.getReg(), &PPC::WACC_HIRCRegClass, MRI) &&
+                   IsRegInClass(SrcMO.getReg(), &PPC::WACCRCRegClass, MRI)) {
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lei137 wrote:

Good to add a comment about the type of copy this is meant to do similar to the blocks above.


https://github.com/llvm/llvm-project/pull/149129