[llvm] [AMDGPU] SelectionDAG divergence tracking should take into account Target divergency. (PR #144947)

[Jay Foad via llvm-commits]

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@@ -10929,7 +10931,8 @@ SDNode *SelectionDAG::UpdateNodeOperands(SDNode *N, SDValue Op) {
   // Now we update the operands.
   N->OperandList[0].set(Op);
 
-  updateDivergence(N);
+  if (DivergentTarget)
+    updateDivergence(N);
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jayfoad wrote:

I think I'd prefer putting `if (!DivergentTarget) return` as the first thing inside `updateDivergence`, to keep the call sites as simple as possible.

https://github.com/llvm/llvm-project/pull/144947