[llvm] [RISCV] Enable bidirectional postra scheduling (PR #115864)

[Craig Topper via llvm-commits]

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@@ -1438,6 +1438,20 @@ def TunePreferWInst
     : SubtargetFeature<"prefer-w-inst", "PreferWInst", "true",
                        "Prefer instructions with W suffix">;
 
+let SetMaxValue = false in {
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topperc wrote:

Can we put this in TuneInfo instead? Seems wasteful to allocate 3 subtarget bits for something that already has command line options in the scheduler. We just need to be able to map CPU to a value just like cache size or prefetch distance right?

https://github.com/llvm/llvm-project/pull/115864