[clang] [llvm] [SPIRV] Use AMDGPU ABI for AMDGCN flavoured SPIRV (PR #169865)

[Alex Voicu via llvm-commits]

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@@ -9,6 +9,11 @@
 #include "ABIInfoImpl.h"
 #include "HLSLBufferLayoutBuilder.h"
 #include "TargetInfo.h"
+#include "clang/Basic/LangOptions.h"
+#include "llvm/IR/DerivedTypes.h"
+
+#include <stdint.h>
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AlexVlx wrote:

Conventionally, `cstdint` is for `std::foo_t`, and `stdint.h` is for `foo_t` without the namespace. Now, the convention is weak and often broken, [but it exists](https://stackoverflow.com/a/13643019). As for needing it, there are `uint64_t` uses, and whilst transitively `cstdint` / `stdint.h` is extremely likely to get included, I thought that we want to make files as self sufficient as possible.

https://github.com/llvm/llvm-project/pull/169865