[llvm] [SPIR-V] Support extension toggling and enabling all (PR #85503)

[Arvind Sudarsanam via llvm-commits]

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@@ -0,0 +1,37 @@
+//===--- SPIRVCommandLine.h ---- Command Line Options -----------*- 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 file contains classes and functions needed for processing, parsing, and
+// using CLI options for the SPIR-V backend.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_TARGET_SPIRV_COMMANDLINE_H
+#define LLVM_LIB_TARGET_SPIRV_COMMANDLINE_H
+
+#include "MCTargetDesc/SPIRVBaseInfo.h"
+#include "llvm/Support/CommandLine.h"
+#include <set>
+
+namespace llvm {
+
+struct SPIRVExtensionsParser
+    : public cl::parser<std::set<SPIRV::Extension::Extension>> {
+public:
+  SPIRVExtensionsParser(cl::Option &O)
+      : cl::parser<std::set<SPIRV::Extension::Extension>>(O) {}
+
+  /// Parses SPIR-V extension name from a CLI arguments.
----------------
asudarsa wrote:

```suggestion
  /// Parses SPIR-V extension name from CLI arguments.
```

https://github.com/llvm/llvm-project/pull/85503