[llvm] [AMDGPU] Determine MCFixupKind in a more general way. NFCI. (PR #155864)

[Jay Foad via llvm-commits]

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@@ -695,11 +695,8 @@ void AMDGPUMCCodeEmitter::getMachineOpValueCommon(
     const MCInstrDesc &Desc = MCII.get(MI.getOpcode());
     uint32_t Offset = Desc.getSize();
     assert(Offset == 4 || Offset == 8);
-    auto OpType = Desc.operands()[OpNo].OperandType;
-    MCFixupKind Kind = (STI.hasFeature(AMDGPU::Feature64BitLiterals) &&
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jayfoad wrote:

I don't think the test for Feature64BitLiterals was really needed here. If we don't have the feature then we should not have reached here with a 64-bit operand type.

https://github.com/llvm/llvm-project/pull/155864