[clang] [CIR] Upstream builtin lowering emitter & FAbs op (PR #151750)

[Andy Kaylor via cfe-commits]

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@@ -3199,4 +3199,22 @@ def CIR_ExpectOp : CIR_Op<"expect", [
   }];
 }
 
+//===----------------------------------------------------------------------===//
+// Floating Point Ops
+//===----------------------------------------------------------------------===//
+
+class CIR_UnaryFPToFPBuiltinOp<string mnemonic, string llvmOpName>
+    : CIR_Op<mnemonic, [Pure, SameOperandsAndResultType]>
+{
+  let arguments = (ins CIR_AnyFloatOrVecOfFloatType:$src);
+  let results = (outs CIR_AnyFloatOrVecOfFloatType:$result);
+  let summary = "libc builtin equivalent ignoring "
+                "floating point exceptions and errno";
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andykaylor wrote:

It doesn't really make sense to say that this is libc equivalent, when one of its primary characteristics is a difference from the libc function. Do we need a summary here at all? I'd prefer to see individual summaries on the operations that derive from this, even knowing that they will be very similar.


https://github.com/llvm/llvm-project/pull/151750