[Test] Add test showing bug in SCEV::getBackedgeTakenInfo (NFC)

Test for #62380.

Author: d-makogon

llvm/test/Analysis/ScalarEvolution/pr62380.ll

@@ -0,0 +1,55 @@
+; RUN: opt -passes='loop(loop-deletion),loop-mssa(loop-predication,licm<allowspeculation>,simple-loop-unswitch<nontrivial>),loop(loop-predication)' -S < %s | FileCheck %s
+
+; REQUIRES: asserts
+; XFAIL: *
+
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128-ni:1-p2:32:8:8:32-ni:2"
+target triple = "x86_64-unknown-linux-gnu"
+
+define void @test(i32 %arg) {
+bb:
+  br label %bb1
+
+bb1:                                              ; preds = %bb2, %bb
+  %load = load i32, ptr null, align 4
+  br label %bb2
+
+bb2:                                              ; preds = %bb1
+  br i1 false, label %bb3, label %bb1
+
+bb3:                                              ; preds = %bb6, %bb2
+  %phi = phi i32 [ %add, %bb6 ], [ 0, %bb2 ]
+  %add = add i32 %phi, 1
+  %icmp = icmp ult i32 %phi, %load
+  br i1 %icmp, label %bb5, label %bb4
+
+bb4:                                              ; preds = %bb3
+  ret void
+
+bb5:                                              ; preds = %bb3
+  %call = call i1 @llvm.experimental.widenable.condition()
+  br i1 %call, label %bb9, label %bb14
+
+bb6:                                              ; preds = %bb9
+  %add7 = add i32 %phi10, 1
+  %icmp8 = icmp ugt i32 %phi10, 1
+  br i1 %icmp8, label %bb3, label %bb9
+
+bb9:                                              ; preds = %bb6, %bb5
+  %phi10 = phi i32 [ %add7, %bb6 ], [ %phi, %bb5 ]
+  %icmp11 = icmp ult i32 %phi10, %arg
+  %call12 = call i1 @llvm.experimental.widenable.condition()
+  %and = and i1 %icmp11, %call12
+  br i1 %and, label %bb6, label %bb13
+
+bb13:                                             ; preds = %bb9
+  ret void
+
+bb14:                                             ; preds = %bb5
+  ret void
+}
+
+; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(inaccessiblemem: readwrite)
+declare noundef i1 @llvm.experimental.widenable.condition() #0
+
+attributes #0 = { nocallback nofree nosync nounwind speculatable willreturn memory(inaccessiblemem: readwrite) }