[llvm] [AMDGPU][AsmParser] Eliminate validateExeczVcczOperands(). (PR #102600)

[Stanislav Mekhanoshin via llvm-commits]

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@@ -3039,7 +3038,8 @@ bool AMDGPUAsmParser::ParseAMDGPURegister(RegisterKind &RegKind, unsigned &Reg,
     if (Reg == AMDGPU::SGPR_NULL) {
       Error(Loc, "'null' operand is not supported on this GPU");
     } else {
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rampitec wrote:

Actually it does not return, but can be used as `return Error()` instead.

https://github.com/llvm/llvm-project/pull/102600