[libclc] [libclc] Implement integer __clc_abs using __builtin_elementwise_abs (PR #164957)

[Wenju He via cfe-commits]

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@@ -6,7 +6,14 @@
 //
 //===----------------------------------------------------------------------===//
 
+#ifdef __CLC_GEN_S
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wenju-he wrote:

> Does this define exist? I remember it downstream but haven't seen it upstream.

You're right, thanks. I'll add it to upstream.

https://github.com/llvm/llvm-project/pull/164957