[clang] [AMDGPU] Treat printf as builtin for OpenCL (PR #72554)

[Vikram Hegde via cfe-commits]

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@@ -406,5 +410,9 @@ TARGET_BUILTIN(__builtin_amdgcn_cvt_pk_fp8_f32, "iffiIb", "nc", "fp8-insts")
 TARGET_BUILTIN(__builtin_amdgcn_cvt_sr_bf8_f32, "ifiiIi", "nc", "fp8-insts")
 TARGET_BUILTIN(__builtin_amdgcn_cvt_sr_fp8_f32, "ifiiIi", "nc", "fp8-insts")
 
+// OpenCL
+LANGBUILTIN(printf, "icC*4.", "fp:0:", ALL_OCL_LANGUAGES)
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vikramRH wrote:

This is specifically to recognize the OpenCL version of printf (where fmt string arg is a pointer to const address space) as a builtin. The hack to generic builtin is just a option that I had as I did not want to add a new case to builtin expansion code (since the API used by both OpenCL and HIP are same ), however Im okay with adding a new case too if you feel it makes more sense.

https://github.com/llvm/llvm-project/pull/72554