[llvm] [IR] Add `llvm.sincos` intrinsic (PR #109825)

[Benjamin Maxwell via llvm-commits]

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@@ -4429,6 +4435,22 @@ SDValue DAGTypeLegalizer::SplitVecOp_VECTOR_HISTOGRAM(SDNode *N) {
 //  Result Vector Widening
 //===----------------------------------------------------------------------===//
 
+void DAGTypeLegalizer::ReplaceOtherWidenResult(SDNode *N, SDNode *WidenNode,
+                                               unsigned WidenResNo) {
+  assert(N->getNumValues() == 2 && "expected node with two results");
+  unsigned OtherNo = 1 - WidenResNo;
+  EVT OtherVT = N->getValueType(OtherNo);
+  if (getTypeAction(OtherVT) == TargetLowering::TypeWidenVector) {
+    SetWidenedVector(SDValue(N, OtherNo), SDValue(WidenNode, OtherNo));
+  } else {
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MacDue wrote:

Every `_UnaryOpWithTwoResults` method currently assumes both results are vectors (of the same element count), which has to hold for both `FSINCOS` and `FREXPR`. I'm not sure it should be further generalized while there are no nodes with mismatched values. Maybe the name could be changed to make this assumption explicit?

https://github.com/llvm/llvm-project/pull/109825