[llvm] [SPIR-V] Add SPIR-V structurizer (PR #97606)

[Michal Paszkowski via llvm-commits]

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@@ -0,0 +1,649 @@
+//===-- SPIRVStructurizer.cpp -----------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This pass adds the required OpSelection/OpLoop merge instructions to
+// generate valid SPIR-V.
+// This pass trims convergence intrinsics as those were only useful when
+// modifying the CFG during IR passes.
+//
+//===----------------------------------------------------------------------===//
+
+#include <stack>
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michalpaszkowski wrote:

Please list system includes at the end. The [expected order can be found here](https://llvm.org/docs/CodingStandards.html#id16).

https://github.com/llvm/llvm-project/pull/97606