[clang] [HIP][SPIRV] Enable the SPIRV backend instead of the translator through an experimental flag. (PR #162282)

[Joseph Huber via cfe-commits]

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@@ -78,6 +78,7 @@ TYPE("c++-module-cpp-output",    PP_CXXModule, INVALID,         "iim",    phases
 TYPE("ada",                      Ada,          INVALID,         nullptr,  phases::Compile, phases::Backend, phases::Assemble, phases::Link)
 TYPE("assembler",                PP_Asm,       INVALID,         "s",      phases::Assemble, phases::Link)
 TYPE("assembler-with-cpp",       Asm,          PP_Asm,          "S",      phases::Preprocess, phases::Assemble, phases::Link)
+TYPE("spv",                      SPV,          INVALID,         "spv",  phases::Backend)
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jhuber6 wrote:

SPIR-V in this context is just the assembler face as far as I'm aware, I think there's some magic setting that splits it if you need to. That's what CUDA does w/ its PTX target. I'd imagine this would imply clang consuming SPIR-V to give you back an ELF or LLVM-IR.

https://github.com/llvm/llvm-project/pull/162282