[llvm] [AMDGPU][True16][CodeGen]Support V2S copy with True16 flow (PR #118037)

[Joe Nash via llvm-commits]

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@@ -1075,10 +1075,25 @@ void SIFixSGPRCopies::lowerVGPR2SGPRCopies(MachineFunction &MF) {
         TRI->getRegClassForOperandReg(*MRI, MI->getOperand(1));
     size_t SrcSize = TRI->getRegSizeInBits(*SrcRC);
     if (SrcSize == 16) {
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Sisyph wrote:

This code fixed the conformance test I was looking at, and as you say it should be handled here, so I think it should be merged. 
Regarding an 'alternative fix', do you have any hypothesis what that would be? Is it a priority to find that?

https://github.com/llvm/llvm-project/pull/118037