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

[Manuel Carrasco via cfe-commits]

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@@ -5483,6 +5483,20 @@ defm wavefrontsize64 : SimpleMFlag<"wavefrontsize64",
 defm amdgpu_precise_memory_op
     : SimpleMFlag<"amdgpu-precise-memory-op", "Enable", "Disable",
                   " precise memory mode (AMDGPU only)">;
+def amdgpu_use_experimental_spirv_backend
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mgcarrasco wrote:

Thanks @arsenm, you're right. Now we use hip instead. 

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