; LLVM IR from kaynewbie/algorithm :: algorithm/LeetCode/Easy (longest-palindromic-substring)

; Unoptimized IR (clang -disable-llvm-passes):
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"

@.str.1 = external hidden unnamed_addr constant [5 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [15 x i8], align 1
@.str.3 = external hidden unnamed_addr constant [4 x i8], align 1
@.str.4 = external hidden unnamed_addr constant [6 x i8], align 1

; Function Attrs: nounwind uwtable
declare dso_local ptr @longestPalindromicSubstring(ptr noundef, i32 noundef) #0

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1

declare i32 @printf(ptr noundef, ...) #2

; Function Attrs: nounwind uwtable
define dso_local void @testLongestPalindromicSubstring() #0 {
  %1 = alloca ptr, align 8
  %2 = alloca i32, align 4
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  call void @llvm.lifetime.start.p0(i64 8, ptr %1) #3
  store ptr @.str.1, ptr %1, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #3
  store i32 0, ptr %2, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #3
  %6 = load ptr, ptr %1, align 8, !tbaa !5
  store ptr %6, ptr %3, align 8, !tbaa !5
  br label %7

7:                                                ; preds = %13, %0
  %8 = load ptr, ptr %3, align 8, !tbaa !5
  %9 = getelementptr inbounds i8, ptr %8, i32 1
  store ptr %9, ptr %3, align 8, !tbaa !5
  %10 = load i8, ptr %8, align 1, !tbaa !11
  %11 = sext i8 %10 to i32
  %12 = icmp ne i32 %11, 0
  br i1 %12, label %13, label %16

13:                                               ; preds = %7
  %14 = load i32, ptr %2, align 4, !tbaa !9
  %15 = add nsw i32 %14, 1
  store i32 %15, ptr %2, align 4, !tbaa !9
  br label %7, !llvm.loop !12

16:                                               ; preds = %7
  %17 = load i32, ptr %2, align 4, !tbaa !9
  %18 = call i32 (ptr, ...) @printf(ptr noundef @.str.2, i32 noundef %17)
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #3
  %19 = load ptr, ptr %1, align 8, !tbaa !5
  %20 = load i32, ptr %2, align 4, !tbaa !9
  %21 = call ptr @longestPalindromicSubstring(ptr noundef %19, i32 noundef %20)
  store ptr %21, ptr %4, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #3
  %22 = load ptr, ptr %4, align 8, !tbaa !5
  store ptr %22, ptr %5, align 8, !tbaa !5
  br label %23

23:                                               ; preds = %33, %16
  %24 = load ptr, ptr %5, align 8, !tbaa !5
  %25 = icmp ne ptr %24, null
  br i1 %25, label %26, label %31

26:                                               ; preds = %23
  %27 = load ptr, ptr %5, align 8, !tbaa !5
  %28 = load i8, ptr %27, align 1, !tbaa !11
  %29 = sext i8 %28 to i32
  %30 = icmp ne i32 %29, 0
  br label %31

31:                                               ; preds = %26, %23
  %32 = phi i1 [ false, %23 ], [ %30, %26 ]
  br i1 %32, label %33, label %39

33:                                               ; preds = %31
  %34 = load ptr, ptr %5, align 8, !tbaa !5
  %35 = getelementptr inbounds i8, ptr %34, i32 1
  store ptr %35, ptr %5, align 8, !tbaa !5
  %36 = load i8, ptr %34, align 1, !tbaa !11
  %37 = sext i8 %36 to i32
  %38 = call i32 (ptr, ...) @printf(ptr noundef @.str.3, i32 noundef %37)
  br label %23, !llvm.loop !14

39:                                               ; preds = %31
  %40 = call i32 (ptr, ...) @printf(ptr noundef @.str.4)
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr %1) #3
  ret void
}

attributes #0 = { nounwind uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #1 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #3 = { nounwind }

!llvm.module.flags = !{!0, !1, !2, !3}
!llvm.ident = !{!4}

!0 = !{i32 1, !"wchar_size", i32 4}
!1 = !{i32 8, !"PIC Level", i32 2}
!2 = !{i32 7, !"PIE Level", i32 2}
!3 = !{i32 7, !"uwtable", i32 2}
!4 = !{!"clang version 19.1.0 (git@github.com:llvm/llvm-project.git a4bf6cd7cfb1a1421ba92bca9d017b49936c55e4)"}
!5 = !{!6, !6, i64 0}
!6 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"int", !7, i64 0}
!11 = !{!7, !7, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}
!14 = distinct !{!14, !13}


; Optimized IR (opt -passes='default<O3>'):
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"

@.str.1 = external hidden unnamed_addr constant [5 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [15 x i8], align 1
@.str.3 = external hidden unnamed_addr constant [4 x i8], align 1
@.str.4 = external hidden unnamed_addr constant [6 x i8], align 1

; Function Attrs: nounwind uwtable
declare dso_local ptr @longestPalindromicSubstring(ptr noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #1

; Function Attrs: nounwind uwtable
define dso_local void @testLongestPalindromicSubstring() local_unnamed_addr #0 {
  %1 = load i8, ptr @.str.1, align 1, !tbaa !5
  %.not14 = icmp eq i8 %1, 0
  br i1 %.not14, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %0, %.lr.ph
  %.0916 = phi i32 [ %3, %.lr.ph ], [ 0, %0 ]
  %.01015 = phi ptr [ %2, %.lr.ph ], [ @.str.1, %0 ]
  %2 = getelementptr inbounds i8, ptr %.01015, i64 1
  %3 = add nuw nsw i32 %.0916, 1
  %4 = load i8, ptr %2, align 1, !tbaa !5
  %.not = icmp eq i8 %4, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !8

._crit_edge:                                      ; preds = %.lr.ph, %0
  %.09.lcssa = phi i32 [ 0, %0 ], [ %3, %.lr.ph ]
  %5 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.2, i32 noundef %.09.lcssa)
  %6 = tail call ptr @longestPalindromicSubstring(ptr noundef nonnull @.str.1, i32 noundef %.09.lcssa)
  %.not1217 = icmp eq ptr %6, null
  br i1 %.not1217, label %.critedge, label %.lr.ph20.preheader

.lr.ph20.preheader:                               ; preds = %._crit_edge
  %7 = load i8, ptr %6, align 1, !tbaa !5
  %.not1322 = icmp eq i8 %7, 0
  br i1 %.not1322, label %.critedge, label %.lr.ph20

.lr.ph20:                                         ; preds = %.lr.ph20.preheader, %.lr.ph20
  %8 = phi i8 [ %12, %.lr.ph20 ], [ %7, %.lr.ph20.preheader ]
  %.01823 = phi ptr [ %10, %.lr.ph20 ], [ %6, %.lr.ph20.preheader ]
  %9 = sext i8 %8 to i32
  %10 = getelementptr inbounds i8, ptr %.01823, i64 1
  %11 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.3, i32 noundef %9)
  %12 = load i8, ptr %10, align 1, !tbaa !5
  %.not13 = icmp eq i8 %12, 0
  br i1 %.not13, label %.critedge, label %.lr.ph20

.critedge:                                        ; preds = %.lr.ph20, %.lr.ph20.preheader, %._crit_edge
  %13 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.4)
  ret void
}

attributes #0 = { nounwind uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
attributes #1 = { nofree nounwind "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }

!llvm.module.flags = !{!0, !1, !2, !3}
!llvm.ident = !{!4}

!0 = !{i32 1, !"wchar_size", i32 4}
!1 = !{i32 8, !"PIC Level", i32 2}
!2 = !{i32 7, !"PIE Level", i32 2}
!3 = !{i32 7, !"uwtable", i32 2}
!4 = !{!"clang version 19.1.0 (git@github.com:llvm/llvm-project.git a4bf6cd7cfb1a1421ba92bca9d017b49936c55e4)"}
!5 = !{!6, !6, i64 0}
!6 = !{!"omnipotent char", !7, i64 0}
!7 = !{!"Simple C/C++ TBAA"}
!8 = distinct !{!8, !9}
!9 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: EarlyCSEPass,GVNPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,SCCPPass,SROAPass,SimplifyCFGPass,TailCallElimPass