[llvm] [PowerPC] Add phony subregisters to cover the high half of the VSX registers. (PR #94628)

[Kai Luo via llvm-commits]

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@@ -750,25 +750,21 @@ entry:
 define <2 x double> @testDoubleImm1(<2 x double> %a, double %b) {
 ; CHECK-64-LABEL: testDoubleImm1:
 ; CHECK-64:       # %bb.0: # %entry
-; CHECK-64-NEXT:    # kill: def $f1 killed $f1 def $vsl1
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bzEq wrote:

If the phony lane isn't alive at the COPY, I think it's ok we don't have the `implicit-def vsl1`.

https://github.com/llvm/llvm-project/pull/94628