[llvm] [SelectionDAGBuilder] Fix non-determanism in `shouldKeepJumpConditionsTogether` (PR #83687)

[via llvm-commits]

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@@ -2555,31 +2562,19 @@ bool SelectionDAGBuilder::shouldKeepJumpConditionsTogether(
     return true;
   };
 
-  // Prune instructions from RHS Deps that are dependencies of unrelated
-  // instructions. The value (SelectionDAG::MaxRecursionDepth) is fairly
-  // arbitrary and just meant to cap the how much time we spend in the pruning
-  // loop. Its highly unlikely to come into affect.
-  const unsigned MaxPruneIters = SelectionDAG::MaxRecursionDepth;
-  // Stop after a certain point. No incorrectness from including too many
-  // instructions.
-  for (unsigned PruneIters = 0; PruneIters < MaxPruneIters; ++PruneIters) {
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goldsteinn wrote:

err... brain farted and forgot that we are progressively dropping deps.

Let me re-post, ill just do you smallmapvector idea.

https://github.com/llvm/llvm-project/pull/83687