[clang] [llvm] [LLVMABI][AMDGPU] Add an AMDGPU target to the ABI library (PR #223259)

[Arseniy Obolenskiy via cfe-commits]

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@@ -116,6 +123,29 @@ enum class AArch64ABIKind {
 LLVM_ABI std::unique_ptr<TargetInfo>
 createAArch64TargetInfo(TypeBuilder &TB, AArch64ABIKind Kind);
 
+/// The parts of the AMDGPU ABI that differ between amdgcn and the
+/// AMDGCN-flavoured SPIR-V that lowers to it. Address spaces are target
+/// address space numbers, not language address spaces.
+struct AMDGPUABIOptions {
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aobolensk wrote:

simplified the struct, only 3 fields left: ConstantAddrSpace, GenericAddrSpace and CoerceKernelPointerArgs 

https://github.com/llvm/llvm-project/pull/223259