[llvm] [X86][GlobalISel] Add instruction selection for G_SELECT (PR #70753)

[Matt Arsenault via llvm-commits]

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@@ -1789,6 +1793,47 @@ bool X86InstructionSelector::selectMulDivRem(MachineInstr &I,
   return true;
 }
 
+bool X86InstructionSelector::selectSelect(MachineInstr &I,
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arsenm wrote:

Is there a reason this isn't using tablegen? As far as I can tell the DAG is not manually selecting this 

https://github.com/llvm/llvm-project/pull/70753