[clang] [llvm] Add normalize builtins and normalize HLSL function to DirectX and SPIR-V backend (PR #102683)

[Farzon Lotfi via cfe-commits]

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@@ -4725,6 +4725,12 @@ def HLSLMad : LangBuiltin<"HLSL_LANG"> {
   let Prototype = "void(...)";
 }
 
+def HLSLNormalize : LangBuiltin<"HLSL_LANG"> {
+  let Spellings = ["__builtin_hlsl_normalize"];
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farzonl wrote:

is this an elementwise case? isnt it  `n = normalize(x)  = n[i] = x[i]/ length(x)`

https://github.com/llvm/llvm-project/pull/102683