[llvm] [GlobalISel] Skip match table for opcodes with no combines (PR #196017)

[Alexis Engelke via llvm-commits]

https://github.com/aengelke commented:

Can you provide more details on what's so expensive about executeMatchTable (or one of the other function calls) in case there's no combine? The very first instruction is GIM_SwitchOpcode, which should in principle be almost as efficient as this switch.

https://github.com/llvm/llvm-project/pull/196017