[clang] [CIR] Upstream DivOp for ComplexType (PR #153796)

[Andy Kaylor via cfe-commits]

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@@ -3013,6 +3014,47 @@ def CIR_ComplexMulOp : CIR_Op<"complex.mul", [
   }];
 }
 
+def CIR_ComplexDivOp : CIR_Op<"complex.div", [
+  Pure, SameOperandsAndResultType
+]> {
+  let summary = "Complex division";
+  let description = [{
+    The `cir.complex.div` operation takes two complex numbers and returns
+    their quotient.
+
+    For complex types with floating-point components, the `range` attribute
+    specifies the algorithm to be used when the operation is lowered to
+    the LLVM dialect. For division, 'improved' produces Smith's algorithms for
+    Complex division with no additional handling for NaN values. If 'promoted'
+    is used, the values are promoted to a higher precision type, if possible,
+    and the calculation is performed using the algebraic formula, with
+    no additional handling for NaN values. We fall back on Smith's algorithm
+    when the target does not support a higher precision type.
+    If 'full' is used, a runtime-library function is called if one of the
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andykaylor wrote:

The formatting is a bit off here.

https://github.com/llvm/llvm-project/pull/153796