NFC. Add PR44320 IR test case.

Author: DaniilSuchkov

llvm/test/Transforms/LCSSA/pr44320.ll

@@ -0,0 +1,56 @@
+; XFAIL: *
+; RUN: opt -passes="verify<scalar-evolution>,lcssa,verify<scalar-evolution>" -verify-scev-strict -S -disable-output %s
+
+; The first SCEV verification is required because it queries SCEV and populates
+; SCEV caches. Second SCEV verification checks if the caches are in valid state.
+
+; Check that the second SCEV verification doesn't fail.
+define void @test(i32* %arg, i32* %arg1, i1 %arg2, i1 %arg3) {
+bb:
+  br label %bb6
+
+bb5:
+  br label %bb6
+
+bb6:
+  br label %bb7
+
+bb7:
+  %tmp = load i32, i32* %arg
+  %tmp8 = load i32, i32* %arg1
+  %tmp9 = add i32 %tmp8, %tmp
+  %tmp10 = icmp sgt i32 %tmp9, %tmp
+  br i1 %tmp10, label %bb11, label %bb17
+
+bb11:
+  br i1 %arg3, label %bb12, label %bb14
+
+bb12:
+  br label %bb13
+
+bb13:
+  br label %bb17
+
+bb14:
+  br label %bb15
+
+bb15:
+  %tmp16 = add nsw i32 %tmp, 1
+  ret void
+
+bb17:
+  %tmp18 = phi i32 [ 0, %bb7 ], [ %tmp8, %bb13 ]
+  br i1 %arg2, label %bb24, label %bb19
+
+bb19:
+  br label %bb20
+
+bb20:
+  %tmp21 = phi i32 [ %tmp22, %bb20 ], [ 0, %bb19 ]
+  %tmp22 = add nuw nsw i32 %tmp21, 1
+  %tmp23 = icmp slt i32 %tmp22, %tmp18
+  br i1 %tmp23, label %bb20, label %bb5
+
+bb24:
+  ret void
+}