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

[Alex Voicu via cfe-commits]

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@@ -1421,6 +1421,18 @@ def fhip_emit_relocatable : Flag<["-"], "fhip-emit-relocatable">,
   HelpText<"Compile HIP source to relocatable">;
 def fno_hip_emit_relocatable : Flag<["-"], "fno-hip-emit-relocatable">,
   HelpText<"Do not override toolchain to compile HIP source to relocatable">;
+def hip_use_experimental_spirv_backend
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AlexVlx wrote:

This is confusing because it used to be the experimental SPIRV backend before it went out of experimental, so it could be read as using an older iteration of the SPIRV BE, or some WiP iteration of it. Possibly consider deleting the experimental?

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