[clang] [Clang] Unify 'nvptx-arch' and 'amdgpu-arch' into 'offload-arch' (PR #134713)

[Matt Arsenault via cfe-commits]

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@@ -0,0 +1,78 @@
+//===- OffloadArch.cpp - list available GPUs ------------*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Basic/Version.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Path.h"
+
+using namespace llvm;
+
+static cl::opt<bool> Help("h", cl::desc("Alias for -help"), cl::Hidden);
+
+// Mark all our options with this category.
+static cl::OptionCategory OffloadArchCategory("amdgpu-arch options");
+
+cl::opt<bool> Verbose("verbose", cl::desc("Enable verbose output"),
+                      cl::init(false), cl::cat(OffloadArchCategory));
+
+cl::opt<bool> AMDGPU("amdgpu-only", cl::desc("Print only AMD GPUs"),
+                     cl::init(false), cl::cat(OffloadArchCategory));
+
+cl::opt<bool> NVPTX("nvptx-only", cl::desc("Print only NVIDIA GPUs"),
+                    cl::init(false), cl::cat(OffloadArchCategory));
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arsenm wrote:

The way that will work is we will have 10 of these things, and be unable to rename the flag. Just start with it 

https://github.com/llvm/llvm-project/pull/134713