[llvm] [MCA] Do not allocate space for DependenceEdge by default in DependencyGraphNode (NFC) (PR #125080)

[Andrea Di Biagio via llvm-commits]

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@@ -228,7 +228,7 @@ class DependencyGraph {
     unsigned Depth;
 
     DependencyEdge CriticalPredecessor;
-    SmallVector<DependencyEdge, 8> OutgoingEdges;
+    SmallVector<DependencyEdge, 0> OutgoingEdges;
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adibiagio wrote:

I think it is useful to have a comment (not more than a couple of lines) explaining why zero was used for the number of inline elements. Otherwise it would be unclear for the reader why we chose that number in this case.

https://github.com/llvm/llvm-project/pull/125080