[llvm] [CodeGen] Remove unsatisfiable hints in RegAllocGreedy. (PR #190983)

[Quentin Colombet via llvm-commits]

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@@ -2971,6 +2997,7 @@ bool RAGreedy::run(MachineFunction &mf) {
                                             *VRM, *VRAI, Matrix));
 
   VRAI->calculateSpillWeightsAndHints();
+  removeUnsatisfiableHints();
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qcolombet wrote:

We'll need to call that before the calculateSpillWeightsAndHints because IIRC we do some boost as well in the spill cost for hints (albeit much smaller boost).

https://github.com/llvm/llvm-project/pull/190983