; LLVM IR from devparthgarg/Data-Structures-and-Algorithms :: 06. Searching/05 Count 1s in Sorted Binary Array/05b.ll (Z7count1sPii)

; 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 noundef i32 @_Z7count1sPii(ptr noundef %0, i32 noundef %1) #0 {
  %3 = alloca i32, align 4
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  %8 = alloca i32, align 4
  %9 = alloca i32, align 4
  store ptr %0, ptr %4, align 8, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  store i32 0, ptr %6, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #2
  %10 = load i32, ptr %5, align 4, !tbaa !9
  %11 = sub nsw i32 %10, 1
  store i32 %11, ptr %7, align 4, !tbaa !9
  br label %12

12:                                               ; preds = %57, %2
  %13 = load i32, ptr %6, align 4, !tbaa !9
  %14 = load i32, ptr %7, align 4, !tbaa !9
  %15 = icmp sle i32 %13, %14
  br i1 %15, label %16, label %58

16:                                               ; preds = %12
  call void @llvm.lifetime.start.p0(i64 4, ptr %8) #2
  %17 = load i32, ptr %6, align 4, !tbaa !9
  %18 = load i32, ptr %7, align 4, !tbaa !9
  %19 = add nsw i32 %17, %18
  %20 = sdiv i32 %19, 2
  store i32 %20, ptr %8, align 4, !tbaa !9
  %21 = load ptr, ptr %4, align 8, !tbaa !5
  %22 = load i32, ptr %8, 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
  %26 = icmp eq i32 %25, 0
  br i1 %26, label %27, label %30

27:                                               ; preds = %16
  %28 = load i32, ptr %8, align 4, !tbaa !9
  %29 = add nsw i32 %28, 1
  store i32 %29, ptr %6, align 4, !tbaa !9
  br label %54

30:                                               ; preds = %16
  %31 = load i32, ptr %8, align 4, !tbaa !9
  %32 = icmp eq i32 %31, 0
  br i1 %32, label %46, label %33

33:                                               ; preds = %30
  %34 = load ptr, ptr %4, align 8, !tbaa !5
  %35 = load i32, ptr %8, align 4, !tbaa !9
  %36 = sub nsw i32 %35, 1
  %37 = sext i32 %36 to i64
  %38 = getelementptr inbounds i32, ptr %34, i64 %37
  %39 = load i32, ptr %38, align 4, !tbaa !9
  %40 = load ptr, ptr %4, align 8, !tbaa !5
  %41 = load i32, ptr %8, align 4, !tbaa !9
  %42 = sext i32 %41 to i64
  %43 = getelementptr inbounds i32, ptr %40, i64 %42
  %44 = load i32, ptr %43, align 4, !tbaa !9
  %45 = icmp ne i32 %39, %44
  br i1 %45, label %46, label %50

46:                                               ; preds = %33, %30
  %47 = load i32, ptr %5, align 4, !tbaa !9
  %48 = load i32, ptr %8, align 4, !tbaa !9
  %49 = sub nsw i32 %47, %48
  store i32 %49, ptr %3, align 4
  store i32 1, ptr %9, align 4
  br label %55

50:                                               ; preds = %33
  %51 = load i32, ptr %8, align 4, !tbaa !9
  %52 = sub nsw i32 %51, 1
  store i32 %52, ptr %7, align 4, !tbaa !9
  br label %53

53:                                               ; preds = %50
  br label %54

54:                                               ; preds = %53, %27
  store i32 0, ptr %9, align 4
  br label %55

55:                                               ; preds = %54, %46
  call void @llvm.lifetime.end.p0(i64 4, ptr %8) #2
  %56 = load i32, ptr %9, align 4
  switch i32 %56, label %59 [
    i32 0, label %57
  ]

57:                                               ; preds = %55
  br label %12, !llvm.loop !11

58:                                               ; preds = %12
  store i32 0, ptr %3, align 4
  store i32 1, ptr %9, align 4
  br label %59

59:                                               ; preds = %58, %55
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  %60 = load i32, ptr %3, align 4
  ret i32 %60
}

; 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"}


; 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 willreturn memory(argmem: read) uwtable
define dso_local noundef i32 @_Z7count1sPii(ptr nocapture noundef readonly %0, i32 noundef %1) local_unnamed_addr #0 {
  %.not31 = icmp slt i32 %1, 1
  br i1 %.not31, label %.loopexit, label %.lr.ph.preheader

.lr.ph.preheader:                                 ; preds = %2
  %3 = add nsw i32 %1, -1
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.preheader, %20
  %.01833 = phi i32 [ %.220, %20 ], [ %3, %.lr.ph.preheader ]
  %.02132 = phi i32 [ %.223, %20 ], [ 0, %.lr.ph.preheader ]
  %4 = add nuw nsw i32 %.01833, %.02132
  %5 = lshr i32 %4, 1
  %6 = zext nneg i32 %5 to i64
  %7 = getelementptr inbounds i32, ptr %0, i64 %6
  %8 = load i32, ptr %7, align 4, !tbaa !5
  %9 = icmp eq i32 %8, 0
  br i1 %9, label %10, label %12

10:                                               ; preds = %.lr.ph
  %11 = add nuw nsw i32 %5, 1
  br label %20

12:                                               ; preds = %.lr.ph
  %13 = icmp ult i32 %4, 2
  br i1 %13, label %.thread, label %14

14:                                               ; preds = %12
  %15 = add nsw i32 %5, -1
  %16 = zext nneg i32 %15 to i64
  %17 = getelementptr inbounds i32, ptr %0, i64 %16
  %18 = load i32, ptr %17, align 4, !tbaa !5
  %.not26 = icmp eq i32 %18, %8
  br i1 %.not26, label %20, label %.thread

.thread:                                          ; preds = %12, %14
  %19 = sub nsw i32 %1, %5
  br label %.loopexit

20:                                               ; preds = %10, %14
  %.223 = phi i32 [ %11, %10 ], [ %.02132, %14 ]
  %.220 = phi i32 [ %.01833, %10 ], [ %15, %14 ]
  %.not = icmp sgt i32 %.223, %.220
  br i1 %.not, label %.loopexit, label %.lr.ph, !llvm.loop !9

.loopexit:                                        ; preds = %20, %2, %.thread
  %.2 = phi i32 [ %19, %.thread ], [ 0, %2 ], [ 0, %20 ]
  ret i32 %.2
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(argmem: read) 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"}


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