[clang] [clang][SPIR-V] Always add convervence intrinsics (PR #88918)

[Matt Arsenault via cfe-commits]

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@@ -4987,7 +4990,11 @@ class CodeGenFunction : public CodeGenTypeCache {
                                      const llvm::Twine &Name = "");
   // Adds a convergence_ctrl token to |Input| and emits the required parent
   // convergence instructions.
-  llvm::CallBase *addControlledConvergenceToken(llvm::CallBase *Input);
+  template <typename CallType>
+  CallType *addControlledConvergenceToken(CallType *Input) {
+    return dyn_cast<CallType>(
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arsenm wrote:

should just be cast? You also have yet another dyn_cast on the use? 

https://github.com/llvm/llvm-project/pull/88918