Add a test for an intrinsic that is not marked as isTriviallyScalarizable

Since uadd_with_overflow is now marked isTriviallyScalarizable, another intrinsic needs to take its place for testing the bug fix introduced in llvm#113625 for issue llvm#113624.

Author: Icohedron

llvm/test/Transforms/Scalarizer/sincos.ll

@@ -0,0 +1,17 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt %s -passes='function(scalarizer)' -S | FileCheck %s
+
+; Test to make sure that struct return intrinsics that are not `isTriviallyScalarizable` do not get scalarized.
+
+define <4 x float> @test_(<4 x float> %Val) {
+; CHECK-LABEL: define <4 x float> @test_(
+; CHECK-SAME: <4 x float> [[VAL:%.*]]) {
+; CHECK-NEXT:    [[R:%.*]] = call { <4 x float>, <4 x float> } @llvm.sincos.v4f32(<4 x float> [[VAL]])
+; CHECK-NEXT:    [[EL:%.*]] = extractvalue { <4 x float>, <4 x float> } [[R]], 0
+; CHECK-NEXT:    ret <4 x float> [[EL]]
+;
+  %r = call { <4 x float>, <4 x float> } @llvm.sincos.v4f32(<4 x float>  %Val)
+  %el = extractvalue { <4 x float>, <4 x float> } %r, 0
+  ret <4 x float> %el
+}
+