; LLVM IR from Algo-Phantoms/Algo-Tree :: Code/C++/shell_sort.ll (Z9ShellSortPii)

; 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"

; Function Attrs: mustprogress nounwind uwtable
define dso_local void @_Z9ShellSortPii(ptr noundef %0, i32 noundef %1) #0 {
  %3 = alloca ptr, align 8
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  %8 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  store i32 %1, ptr %4, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #2
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #2
  call void @llvm.lifetime.start.p0(i64 4, ptr %8) #2
  %9 = load i32, ptr %4, align 4, !tbaa !9
  %10 = sdiv i32 %9, 2
  store i32 %10, ptr %5, align 4, !tbaa !9
  br label %11

11:                                               ; preds = %69, %2
  %12 = load i32, ptr %5, align 4, !tbaa !9
  %13 = icmp sge i32 %12, 1
  br i1 %13, label %14, label %72

14:                                               ; preds = %11
  %15 = load i32, ptr %5, align 4, !tbaa !9
  store i32 %15, ptr %6, align 4, !tbaa !9
  br label %16

16:                                               ; preds = %65, %14
  %17 = load i32, ptr %6, align 4, !tbaa !9
  %18 = load i32, ptr %4, align 4, !tbaa !9
  %19 = icmp slt i32 %17, %18
  br i1 %19, label %20, label %68

20:                                               ; preds = %16
  %21 = load ptr, ptr %3, align 8, !tbaa !5
  %22 = load i32, ptr %6, align 4, !tbaa !9
  %23 = sext i32 %22 to i64
  %24 = getelementptr inbounds i32, ptr %21, i64 %23
  %25 = load i32, ptr %24, align 4, !tbaa !9
  store i32 %25, ptr %8, align 4, !tbaa !9
  %26 = load i32, ptr %6, align 4, !tbaa !9
  %27 = load i32, ptr %5, align 4, !tbaa !9
  %28 = sub nsw i32 %26, %27
  store i32 %28, ptr %7, align 4, !tbaa !9
  br label %29

29:                                               ; preds = %42, %20
  %30 = load i32, ptr %7, align 4, !tbaa !9
  %31 = icmp sge i32 %30, 0
  br i1 %31, label %32, label %40

32:                                               ; preds = %29
  %33 = load ptr, ptr %3, align 8, !tbaa !5
  %34 = load i32, ptr %7, align 4, !tbaa !9
  %35 = sext i32 %34 to i64
  %36 = getelementptr inbounds i32, ptr %33, i64 %35
  %37 = load i32, ptr %36, align 4, !tbaa !9
  %38 = load i32, ptr %8, align 4, !tbaa !9
  %39 = icmp sgt i32 %37, %38
  br label %40

40:                                               ; preds = %32, %29
  %41 = phi i1 [ false, %29 ], [ %39, %32 ]
  br i1 %41, label %42, label %57

42:                                               ; preds = %40
  %43 = load ptr, ptr %3, align 8, !tbaa !5
  %44 = load i32, ptr %7, align 4, !tbaa !9
  %45 = sext i32 %44 to i64
  %46 = getelementptr inbounds i32, ptr %43, i64 %45
  %47 = load i32, ptr %46, align 4, !tbaa !9
  %48 = load ptr, ptr %3, align 8, !tbaa !5
  %49 = load i32, ptr %7, align 4, !tbaa !9
  %50 = load i32, ptr %5, align 4, !tbaa !9
  %51 = add nsw i32 %49, %50
  %52 = sext i32 %51 to i64
  %53 = getelementptr inbounds i32, ptr %48, i64 %52
  store i32 %47, ptr %53, align 4, !tbaa !9
  %54 = load i32, ptr %7, align 4, !tbaa !9
  %55 = load i32, ptr %5, align 4, !tbaa !9
  %56 = sub nsw i32 %54, %55
  store i32 %56, ptr %7, align 4, !tbaa !9
  br label %29, !llvm.loop !11

57:                                               ; preds = %40
  %58 = load i32, ptr %8, align 4, !tbaa !9
  %59 = load ptr, ptr %3, align 8, !tbaa !5
  %60 = load i32, ptr %7, align 4, !tbaa !9
  %61 = load i32, ptr %5, align 4, !tbaa !9
  %62 = add nsw i32 %60, %61
  %63 = sext i32 %62 to i64
  %64 = getelementptr inbounds i32, ptr %59, i64 %63
  store i32 %58, ptr %64, align 4, !tbaa !9
  br label %65

65:                                               ; preds = %57
  %66 = load i32, ptr %6, align 4, !tbaa !9
  %67 = add nsw i32 %66, 1
  store i32 %67, ptr %6, align 4, !tbaa !9
  br label %16, !llvm.loop !13

68:                                               ; preds = %16
  br label %69

69:                                               ; preds = %68
  %70 = load i32, ptr %5, align 4, !tbaa !9
  %71 = sdiv i32 %70, 2
  store i32 %71, ptr %5, align 4, !tbaa !9
  br label %11, !llvm.loop !14

72:                                               ; preds = %11
  call void @llvm.lifetime.end.p0(i64 4, ptr %8) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #2
  ret void
}

; 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

attributes #0 = { mustprogress 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 = { 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, !10, i64 0}
!10 = !{!"int", !7, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.mustprogress"}
!13 = distinct !{!13, !12}
!14 = distinct !{!14, !12}


; 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 nofree norecurse nosync nounwind memory(argmem: readwrite) uwtable
define dso_local void @_Z9ShellSortPii(ptr nocapture noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = icmp sgt i32 %1, 1
  br i1 %3, label %.preheader, label %._crit_edge36

.preheader:                                       ; preds = %2, %._crit_edge
  %.035.in = phi i32 [ %.035, %._crit_edge ], [ %1, %2 ]
  %.035 = lshr i32 %.035.in, 1
  %4 = icmp slt i32 %.035, %1
  br i1 %4, label %.lr.ph34.preheader, label %._crit_edge

.lr.ph34.preheader:                               ; preds = %.preheader
  %5 = zext nneg i32 %.035 to i64
  br label %.lr.ph.preheader

.lr.ph.preheader:                                 ; preds = %.critedge, %.lr.ph34.preheader
  %indvars.iv = phi i64 [ %5, %.lr.ph34.preheader ], [ %indvars.iv.next, %.critedge ]
  %6 = getelementptr inbounds i32, ptr %0, i64 %indvars.iv
  %7 = load i32, ptr %6, align 4, !tbaa !5
  %8 = trunc nuw i64 %indvars.iv to i32
  %9 = trunc i64 %indvars.iv to i32
  %10 = sub i32 %9, %.035
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.preheader, %15
  %.02530 = phi i32 [ %.025, %15 ], [ %10, %.lr.ph.preheader ]
  %.026.pn29 = phi i32 [ %.02530, %15 ], [ %8, %.lr.ph.preheader ]
  %11 = zext nneg i32 %.02530 to i64
  %12 = getelementptr inbounds i32, ptr %0, i64 %11
  %13 = load i32, ptr %12, align 4, !tbaa !5
  %14 = icmp sgt i32 %13, %7
  br i1 %14, label %15, label %.critedge

15:                                               ; preds = %.lr.ph
  %16 = zext nneg i32 %.026.pn29 to i64
  %17 = getelementptr inbounds i32, ptr %0, i64 %16
  store i32 %13, ptr %17, align 4, !tbaa !5
  %.025 = sub nsw i32 %.02530, %.035
  %18 = icmp sgt i32 %.025, -1
  br i1 %18, label %.lr.ph, label %.critedge, !llvm.loop !9

.critedge:                                        ; preds = %.lr.ph, %15
  %.026.pn.lcssa.ph = phi i32 [ %.026.pn29, %.lr.ph ], [ %.02530, %15 ]
  %19 = sext i32 %.026.pn.lcssa.ph to i64
  %20 = getelementptr inbounds i32, ptr %0, i64 %19
  store i32 %7, ptr %20, align 4, !tbaa !5
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %21 = trunc nuw i64 %indvars.iv.next to i32
  %22 = icmp slt i32 %21, %1
  br i1 %22, label %.lr.ph.preheader, label %._crit_edge, !llvm.loop !11

._crit_edge:                                      ; preds = %.critedge, %.preheader
  %.not = icmp ult i32 %.035.in, 4
  br i1 %.not, label %._crit_edge36, label %.preheader, !llvm.loop !12

._crit_edge36:                                    ; preds = %._crit_edge, %2
  ret void
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind memory(argmem: readwrite) 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, !6, i64 0}
!6 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = distinct !{!11, !10}
!12 = distinct !{!12, !10}


; Effective O3 passes: CorrelatedValuePropagationPass,EarlyCSEPass,GVNPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SCCPPass,SROAPass,SimplifyCFGPass