[libclc] [libclc] Move several 'native' builtins to CLC library (PR #129679)

[Fraser Cormack via cfe-commits]

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@@ -0,0 +1,3 @@
+_CLC_OVERLOAD _CLC_DEF __CLC_GENTYPE __clc_native_exp(__CLC_GENTYPE val) {
+  return __clc_native_exp2(val * M_LOG2E_F);
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frasercrmck wrote:

With #133696 merged, I think this is resolved. AMDGPU still has a custom definition of `__clc_native_exp`, which forwards on to `__clc_native_exp2`, which AMDGPU also (continues to) define as a call to `__builtin_amdgcn_exp2f`.

There's no codegen change with this PR.

https://github.com/llvm/llvm-project/pull/129679