[llvm] [CostModel] Handle vector struct results and cost `llvm.sincos` (PR #123210)

[Benjamin Maxwell via llvm-commits]

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@@ -42,25 +44,31 @@ static cl::opt<bool> TypeBasedIntrinsicCost("type-based-intrinsic-cost",
     cl::desc("Calculate intrinsics cost based only on argument types"),
     cl::init(false));
 
+static cl::opt<bool> LibCallBasedIntrinsicCost(
+    "libcall-based-intrinsic-cost",
+    cl::desc("Calculate intrinsics cost using target library info"),
+    cl::init(false));
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MacDue wrote:

Explained below https://github.com/llvm/llvm-project/pull/123210#discussion_r1965022581 

https://github.com/llvm/llvm-project/pull/123210