[llvm] [RegAllocEvictAdvisor] Add minimum weight ratio heuristic. (PR #98109)

[Quentin Colombet via llvm-commits]

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@@ -0,0 +1,76 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+# RUN: llc %s -mtriple=riscv64 -run-pass=greedy,virtregrewriter \
+# RUN: -min-weight-ratio-needed-to-evict-hint=7.5 -o - | FileCheck %s
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qcolombet wrote:

To go back to what I was saying wrt 7.5. I'm not questioning that this gives you the best outcome in what you measured, what I was asking is why it is.
Essentially what is the explanation that makes 7.5 a good number aside from "it fixes my problem".

https://github.com/llvm/llvm-project/pull/98109