[clang] [CIR] Upstream CreateOp for ComplexType with folder (PR #143192)

[Henrich Lauko via cfe-commits]

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@@ -255,7 +255,13 @@ void CIRGenFunction::emitExprAsInit(const Expr *init, const ValueDecl *d,
     emitScalarInit(init, getLoc(d->getSourceRange()), lvalue);
     return;
   case cir::TEK_Complex: {
-    cgm.errorNYI(init->getSourceRange(), "emitExprAsInit: complex type");
+    mlir::Value complex = emitComplexExpr(init);
+    if (capturedByInit)
+      cgm.errorNYI(init->getSourceRange(),
+                   "emitExprAsInit: complex type captured by init");
+    mlir::Location loc = getLoc(init->getExprLoc());
+    emitStoreOfComplex(loc, complex, lvalue,
+                       /*init*/ true);
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xlauko wrote:

```suggestion
                       /*isInit=*/ true);
```

https://github.com/llvm/llvm-project/pull/143192