; LLVM IR from begeekmyfriend/leetcode :: 0162_find_peak_element (peak)

; 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: nounwind uwtable
define dso_local i32 @findPeakElement(ptr noundef %0, i32 noundef %1) #0 {
  %3 = alloca ptr, align 8
  %4 = alloca i32, align 4
  %5 = 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
  store i32 1, ptr %5, align 4, !tbaa !9
  br label %6

6:                                                ; preds = %25, %2
  %7 = load i32, ptr %5, align 4, !tbaa !9
  %8 = load i32, ptr %4, align 4, !tbaa !9
  %9 = icmp slt i32 %7, %8
  br i1 %9, label %10, label %28

10:                                               ; preds = %6
  %11 = load ptr, ptr %3, align 8, !tbaa !5
  %12 = load i32, ptr %5, align 4, !tbaa !9
  %13 = sext i32 %12 to i64
  %14 = getelementptr inbounds i32, ptr %11, i64 %13
  %15 = load i32, ptr %14, align 4, !tbaa !9
  %16 = load ptr, ptr %3, align 8, !tbaa !5
  %17 = load i32, ptr %5, align 4, !tbaa !9
  %18 = sub nsw i32 %17, 1
  %19 = sext i32 %18 to i64
  %20 = getelementptr inbounds i32, ptr %16, i64 %19
  %21 = load i32, ptr %20, align 4, !tbaa !9
  %22 = icmp slt i32 %15, %21
  br i1 %22, label %23, label %24

23:                                               ; preds = %10
  br label %28

24:                                               ; preds = %10
  br label %25

25:                                               ; preds = %24
  %26 = load i32, ptr %5, align 4, !tbaa !9
  %27 = add nsw i32 %26, 1
  store i32 %27, ptr %5, align 4, !tbaa !9
  br label %6, !llvm.loop !11

28:                                               ; preds = %23, %6
  %29 = load i32, ptr %5, align 4, !tbaa !9
  %30 = sub nsw i32 %29, 1
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #2
  ret i32 %30
}

; 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 = { 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/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: nofree norecurse nosync nounwind memory(argmem: read) uwtable
define dso_local range(i32 -2147483648, 2147483647) i32 @findPeakElement(ptr nocapture noundef readonly %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = icmp sgt i32 %1, 1
  br i1 %3, label %.lr.ph.preheader, label %._crit_edge

.lr.ph.preheader:                                 ; preds = %2
  %wide.trip.count = zext nneg i32 %1 to i64
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.preheader, %9
  %indvars.iv = phi i64 [ 1, %.lr.ph.preheader ], [ %indvars.iv.next, %9 ]
  %4 = getelementptr inbounds i32, ptr %0, i64 %indvars.iv
  %5 = load i32, ptr %4, align 4, !tbaa !5
  %6 = getelementptr i8, ptr %4, i64 -4
  %7 = load i32, ptr %6, align 4, !tbaa !5
  %8 = icmp slt i32 %5, %7
  br i1 %8, label %._crit_edge.loopexit.split.loop.exit, label %9

9:                                                ; preds = %.lr.ph
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %exitcond.not = icmp eq i64 %indvars.iv.next, %wide.trip.count
  br i1 %exitcond.not, label %._crit_edge.loopexit, label %.lr.ph, !llvm.loop !9

._crit_edge.loopexit.split.loop.exit:             ; preds = %.lr.ph
  %10 = trunc nuw nsw i64 %indvars.iv to i32
  br label %._crit_edge.loopexit

._crit_edge.loopexit:                             ; preds = %9, %._crit_edge.loopexit.split.loop.exit
  %.0.lcssa.ph = phi i32 [ %10, %._crit_edge.loopexit.split.loop.exit ], [ %1, %9 ]
  %11 = add nsw i32 %.0.lcssa.ph, -1
  br label %._crit_edge

._crit_edge:                                      ; preds = %._crit_edge.loopexit, %2
  %.0.lcssa = phi i32 [ 0, %2 ], [ %11, %._crit_edge.loopexit ]
  ret i32 %.0.lcssa
}

attributes #0 = { nofree norecurse nosync nounwind 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/C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,LCSSAPass,LICMPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass