[clang] [llvm] [clang][OpenMP] Add no-loop SPMD kernel promotion (PR #224041)

[Dhruva Chakrabarti via cfe-commits]

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@@ -146,6 +146,14 @@ class CGOpenMPRuntimeGPU : public CGOpenMPRuntime {
   bool isDelayedVariableLengthDecl(CodeGenFunction &CGF,
                                    const VarDecl *VD) const override;
 
+  /// Check whether the target kernel being emitted is tagged SPMD_NO_LOOP, to
+  /// complete the promotion to a "no-loop" SPMD kernel, mirroring Flang's MLIR
+  /// promotion path.
+  bool canPromoteToNoLoop() const override {
+    return KernelAttrs.ExecFlags ==
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dhruvachak wrote:

I don't like this cache. While today there is no reachable path that gets a wrong answer, not having a directive passed in as the context is error-prone in the future.

https://github.com/llvm/llvm-project/pull/224041