; LLVM IR from div-bargali/Data-Structures-and-Algorithms :: C/Data-Structures/Stack (Stack_using_linked_lists)

; 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"

%struct.stack = type { i32, ptr }

@.str.1 = external hidden unnamed_addr constant [16 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [25 x i8], align 1

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nounwind allocsize(0)
declare noalias ptr @malloc(i64 noundef) #1

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

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nounwind uwtable
define dso_local ptr @pop(ptr noundef %0) #3 {
  %2 = alloca ptr, align 8
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  %6 = load ptr, ptr %3, align 8, !tbaa !5
  %7 = icmp eq ptr %6, null
  br i1 %7, label %8, label %10

8:                                                ; preds = %1
  %9 = call i32 (ptr, ...) @printf(ptr noundef @.str.1)
  store ptr null, ptr %2, align 8
  br label %29

10:                                               ; preds = %1
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #5
  %11 = call noalias ptr @malloc(i64 noundef 16) #6
  store ptr %11, ptr %4, align 8, !tbaa !5
  %12 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %12, ptr %4, align 8, !tbaa !5
  %13 = load ptr, ptr %4, align 8, !tbaa !5
  %14 = getelementptr inbounds %struct.stack, ptr %13, i32 0, i32 0
  %15 = load i32, ptr %14, align 8, !tbaa !9
  %16 = call i32 (ptr, ...) @printf(ptr noundef @.str.2, i32 noundef %15)
  %17 = load ptr, ptr %4, align 8, !tbaa !5
  call void @free(ptr noundef %17) #5
  %18 = load ptr, ptr %3, align 8, !tbaa !5
  %19 = getelementptr inbounds %struct.stack, ptr %18, i32 0, i32 1
  %20 = load ptr, ptr %19, align 8, !tbaa !12
  %21 = icmp eq ptr %20, null
  br i1 %21, label %22, label %23

22:                                               ; preds = %10
  store ptr null, ptr %2, align 8
  store i32 1, ptr %5, align 4
  br label %28

23:                                               ; preds = %10
  %24 = load ptr, ptr %3, align 8, !tbaa !5
  %25 = getelementptr inbounds %struct.stack, ptr %24, i32 0, i32 1
  %26 = load ptr, ptr %25, align 8, !tbaa !12
  store ptr %26, ptr %3, align 8, !tbaa !5
  %27 = load ptr, ptr %3, align 8, !tbaa !5
  store ptr %27, ptr %2, align 8
  store i32 1, ptr %5, align 4
  br label %28

28:                                               ; preds = %23, %22
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #5
  br label %29

29:                                               ; preds = %28, %8
  %30 = load ptr, ptr %2, align 8
  ret ptr %30
}

; Function Attrs: nounwind
declare void @free(ptr noundef) #4

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { nounwind allocsize(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 #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 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 #4 = { 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 #5 = { nounwind }
attributes #6 = { nounwind allocsize(0) }

!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, !11, i64 0}
!10 = !{!"stack", !11, i64 0, !6, i64 8}
!11 = !{!"int", !7, i64 0}
!12 = !{!10, !6, i64 8}


; 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 [16 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [25 x i8], align 1

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #0

; Function Attrs: nounwind uwtable
define dso_local ptr @pop(ptr noundef %0) local_unnamed_addr #1 {
  %2 = icmp eq ptr %0, null
  br i1 %2, label %3, label %5

3:                                                ; preds = %1
  %4 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.1)
  br label %10

5:                                                ; preds = %1
  %6 = load i32, ptr %0, align 8, !tbaa !5
  %7 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.2, i32 noundef %6)
  tail call void @free(ptr noundef nonnull %0) #3
  %8 = getelementptr inbounds i8, ptr %0, i64 8
  %9 = load ptr, ptr %8, align 8, !tbaa !11
  br label %10

10:                                               ; preds = %5, %3
  %.1 = phi ptr [ null, %3 ], [ %9, %5 ]
  ret ptr %.1
}

; Function Attrs: mustprogress nounwind willreturn allockind("free") memory(argmem: readwrite, inaccessiblemem: readwrite)
declare void @free(ptr allocptr nocapture noundef) local_unnamed_addr #2

attributes #0 = { 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 #1 = { 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 #2 = { mustprogress nounwind willreturn allockind("free") memory(argmem: readwrite, inaccessiblemem: readwrite) "alloc-family"="malloc" "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, !7, i64 0}
!6 = !{!"stack", !7, i64 0, !10, i64 8}
!7 = !{!"int", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C/C++ TBAA"}
!10 = !{!"any pointer", !8, i64 0}
!11 = !{!6, !10, i64 8}


; Effective O3 passes: CorrelatedValuePropagationPass,EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,SROAPass,SimplifyCFGPass,TailCallElimPass