[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:

> I'm surprised this didnt' fold in instcombine anyway?

You're right. Thanks for the insight. I have created a PR to fix instcombine: https://github.com/llvm/llvm-project/pull/165200

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