[clang] [CIR] Upstream StackSave and StackRestoreOp (PR #136426)

[Andy Kaylor via cfe-commits]

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@@ -0,0 +1,19 @@
+// RUN: cir-opt %s -cir-to-llvm -o - | FileCheck %s -check-prefix=MLIR
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andykaylor wrote:

Can you also add a RUN line to lower this to LLVM IR?

https://github.com/llvm/llvm-project/pull/136426