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

[Mircea Trofin via llvm-commits]

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@@ -157,6 +163,10 @@ bool DefaultEvictionAdvisor::shouldEvict(const LiveInterval &A, bool IsHint,
     return true;
 
   if (A.weight() > B.weight()) {
+    float WeightRatio = A.weight() / B.weight();
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mtrofin wrote:

can `B.weight()` be 0?

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