; LLVM IR from div-bargali/Data-Structures-and-Algorithms :: C++/Algorithms/Greedy-Algorithms/Huffman.ll (Z12buildMinHeapP7MinHeap)

; 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.MinHeap = type { i32, i32, ptr }

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

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

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z10minHeapifyP7MinHeapi(ptr noundef, i32 noundef) #1

; Function Attrs: mustprogress uwtable
define dso_local void @_Z12buildMinHeapP7MinHeap(ptr noundef %0) #1 {
  %2 = alloca ptr, align 8
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  store ptr %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #2
  %5 = load ptr, ptr %2, align 8, !tbaa !5
  %6 = getelementptr inbounds %struct.MinHeap, ptr %5, i32 0, i32 0
  %7 = load i32, ptr %6, align 8, !tbaa !9
  %8 = sub i32 %7, 1
  store i32 %8, ptr %3, align 4, !tbaa !12
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #2
  %9 = load i32, ptr %3, align 4, !tbaa !12
  %10 = sub nsw i32 %9, 1
  %11 = sdiv i32 %10, 2
  store i32 %11, ptr %4, align 4, !tbaa !12
  br label %12

12:                                               ; preds = %18, %1
  %13 = load i32, ptr %4, align 4, !tbaa !12
  %14 = icmp sge i32 %13, 0
  br i1 %14, label %15, label %21

15:                                               ; preds = %12
  %16 = load ptr, ptr %2, align 8, !tbaa !5
  %17 = load i32, ptr %4, align 4, !tbaa !12
  call void @_Z10minHeapifyP7MinHeapi(ptr noundef %16, i32 noundef %17)
  br label %18

18:                                               ; preds = %15
  %19 = load i32, ptr %4, align 4, !tbaa !12
  %20 = add nsw i32 %19, -1
  store i32 %20, ptr %4, align 4, !tbaa !12
  br label %12, !llvm.loop !13

21:                                               ; preds = %12
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #2
  ret void
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { mustprogress 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 = { 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++ TBAA"}
!9 = !{!10, !11, i64 0}
!10 = !{!"_ZTS7MinHeap", !11, i64 0, !11, i64 4, !6, i64 8}
!11 = !{!"int", !7, i64 0}
!12 = !{!11, !11, i64 0}
!13 = distinct !{!13, !14}
!14 = !{!"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"

; Function Attrs: mustprogress uwtable
declare dso_local void @_Z10minHeapifyP7MinHeapi(ptr noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress uwtable
define dso_local void @_Z12buildMinHeapP7MinHeap(ptr noundef %0) local_unnamed_addr #0 {
  %2 = load i32, ptr %0, align 8, !tbaa !5
  %3 = add i32 %2, -2
  %4 = icmp sgt i32 %3, -2
  br i1 %4, label %.lr.ph.preheader, label %._crit_edge

.lr.ph.preheader:                                 ; preds = %1
  %5 = sdiv i32 %3, 2
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.preheader, %.lr.ph
  %.05 = phi i32 [ %6, %.lr.ph ], [ %5, %.lr.ph.preheader ]
  tail call void @_Z10minHeapifyP7MinHeapi(ptr noundef nonnull %0, i32 noundef %.05)
  %6 = add nsw i32 %.05, -1
  %.not = icmp eq i32 %.05, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !11

._crit_edge:                                      ; preds = %.lr.ph, %1
  ret void
}

attributes #0 = { mustprogress 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" }

!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 = !{!"_ZTS7MinHeap", !7, i64 0, !7, i64 4, !10, i64 8}
!7 = !{!"int", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C++ TBAA"}
!10 = !{!"any pointer", !8, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: CorrelatedValuePropagationPass,EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,SROAPass,SimplifyCFGPass,TailCallElimPass