; LLVM IR from ritikbanger/Hacktoberfest2022-DSA :: 36. C Programs (palindrome)

; 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 = external hidden unnamed_addr constant [16 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [3 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [17 x i8], align 1
@.str.3 = external hidden unnamed_addr constant [21 x i8], align 1

; Function Attrs: nounwind uwtable
define dso_local i32 @main() #0 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #3
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #3
  store i32 0, ptr %5, align 4, !tbaa !5
  %6 = call i32 (ptr, ...) @printf(ptr noundef @.str)
  %7 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str.1, ptr noundef %2)
  %8 = load i32, ptr %2, align 4, !tbaa !5
  store i32 %8, ptr %3, align 4, !tbaa !5
  br label %9

9:                                                ; preds = %12, %0
  %10 = load i32, ptr %2, align 4, !tbaa !5
  %11 = icmp ne i32 %10, 0
  br i1 %11, label %12, label %21

12:                                               ; preds = %9
  %13 = load i32, ptr %2, align 4, !tbaa !5
  %14 = srem i32 %13, 10
  store i32 %14, ptr %4, align 4, !tbaa !5
  %15 = load i32, ptr %5, align 4, !tbaa !5
  %16 = mul nsw i32 %15, 10
  %17 = load i32, ptr %4, align 4, !tbaa !5
  %18 = add nsw i32 %16, %17
  store i32 %18, ptr %5, align 4, !tbaa !5
  %19 = load i32, ptr %2, align 4, !tbaa !5
  %20 = sdiv i32 %19, 10
  store i32 %20, ptr %2, align 4, !tbaa !5
  br label %9, !llvm.loop !9

21:                                               ; preds = %9
  %22 = load i32, ptr %3, align 4, !tbaa !5
  %23 = load i32, ptr %5, align 4, !tbaa !5
  %24 = icmp eq i32 %22, %23
  br i1 %24, label %25, label %28

25:                                               ; preds = %21
  %26 = load i32, ptr %3, align 4, !tbaa !5
  %27 = call i32 (ptr, ...) @printf(ptr noundef @.str.2, i32 noundef %26)
  br label %31

28:                                               ; preds = %21
  %29 = load i32, ptr %3, align 4, !tbaa !5
  %30 = call i32 (ptr, ...) @printf(ptr noundef @.str.3, i32 noundef %29)
  br label %31

31:                                               ; preds = %28, %25
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #3
  %32 = load i32, ptr %1, align 4
  ret i32 %32
}

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

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

declare i32 @__isoc99_scanf(ptr noundef, ...) #2

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

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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}


; 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 = external hidden unnamed_addr constant [16 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [3 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [17 x i8], align 1
@.str.3 = external hidden unnamed_addr constant [21 x i8], align 1

; Function Attrs: nofree nounwind uwtable
define dso_local noundef i32 @main() local_unnamed_addr #0 {
  %1 = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr nonnull %1) #3
  %2 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str)
  %3 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str.1, ptr noundef nonnull %1)
  %4 = load i32, ptr %1, align 4, !tbaa !5
  %.not9 = icmp eq i32 %4, 0
  br i1 %.not9, label %.thread, label %.lr.ph

.lr.ph:                                           ; preds = %0, %.lr.ph
  %.010 = phi i32 [ %8, %.lr.ph ], [ 0, %0 ]
  %5 = phi i32 [ %9, %.lr.ph ], [ %4, %0 ]
  %6 = srem i32 %5, 10
  %7 = mul nsw i32 %.010, 10
  %8 = add nsw i32 %7, %6
  %9 = sdiv i32 %5, 10
  %.off = add i32 %5, 9
  %.not = icmp ult i32 %.off, 19
  br i1 %.not, label %10, label %.lr.ph, !llvm.loop !9

10:                                               ; preds = %.lr.ph
  store i32 %9, ptr %1, align 4, !tbaa !5
  %11 = icmp eq i32 %4, %8
  %spec.select = select i1 %11, ptr @.str.2, ptr @.str.3
  br label %.thread

.thread:                                          ; preds = %10, %0
  %.str.3.sink = phi ptr [ @.str.2, %0 ], [ %spec.select, %10 ]
  %12 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) %.str.3.sink, i32 noundef %4)
  call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %1) #3
  ret i32 0
}

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

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #2

; Function Attrs: nofree nounwind
declare noundef i32 @__isoc99_scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #2

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

attributes #0 = { nofree 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 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { 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" }
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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}


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