LLVM is lowering an integer select I really _really_ want to be a CMOV (it's a binary search and the branch really is basically random) into a branch. It's select in the IR. Sketch of what I'm doing is https://godbolt.org/z/h41WBc - this is a ~30% perf hit. (380c/lookup -> 500c)
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The big hammer is inline ASM, but is there a less drastic way to tell the compiler that no, I really _really_ don't want a branch there?
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Replying to @rygorous
Abandon all hope all ye who enter SelectionDAG
6:10 PM - 2 Apr 2019
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