[llvm] [RFC] implement convergence control in MIR using SelectionDAG (PR #71785)

[Sameer Sahasrabuddhe via llvm-commits]

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@@ -8351,7 +8382,8 @@ void SelectionDAGBuilder::LowerCallTo(const CallBase &CB, SDValue Callee,
       .setConvergent(CB.isConvergent())
       .setIsPreallocated(
           CB.countOperandBundlesOfType(LLVMContext::OB_preallocated) != 0)
-      .setCFIType(CFIType);
+      .setCFIType(CFIType)
+      .setConvergenceControlToken(ConvControlToken);
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ssahasra wrote:

The TD pattern for SI_CALL_ISEL always expects a non-null token, and it is applied independent of whether the call is convergent.

https://github.com/llvm/llvm-project/pull/71785