; LLVM IR from LamberttLiu/CS-Basic-SelfLearning :: 【DSA】数据结构与算法（C语言版本）/src/search (binary_search)

; 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 @BinarySearch(ptr noundef %0, i32 noundef %1, i32 noundef %2) #0 {
  %4 = alloca i32, align 4
  %5 = alloca ptr, align 8
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  %8 = alloca i32, align 4
  %9 = alloca i32, align 4
  %10 = alloca i32, align 4
  %11 = alloca i32, align 4
  store ptr %0, ptr %5, align 8, !tbaa !5
  store i32 %1, ptr %6, align 4, !tbaa !9
  store i32 %2, ptr %7, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %8) #2
  store i32 0, ptr %8, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %9) #2
  %12 = load i32, ptr %6, align 4, !tbaa !9
  %13 = sub nsw i32 %12, 1
  store i32 %13, ptr %9, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %10) #2
  br label %14

14:                                               ; preds = %47, %3
  %15 = load i32, ptr %8, align 4, !tbaa !9
  %16 = load i32, ptr %9, align 4, !tbaa !9
  %17 = icmp sle i32 %15, %16
  br i1 %17, label %18, label %48

18:                                               ; preds = %14
  %19 = load i32, ptr %8, align 4, !tbaa !9
  %20 = load i32, ptr %9, align 4, !tbaa !9
  %21 = add nsw i32 %19, %20
  %22 = sdiv i32 %21, 2
  store i32 %22, ptr %10, align 4, !tbaa !9
  %23 = load ptr, ptr %5, align 8, !tbaa !5
  %24 = load i32, ptr %10, align 4, !tbaa !9
  %25 = sext i32 %24 to i64
  %26 = getelementptr inbounds i32, ptr %23, i64 %25
  %27 = load i32, ptr %26, align 4, !tbaa !9
  %28 = load i32, ptr %7, align 4, !tbaa !9
  %29 = icmp eq i32 %27, %28
  br i1 %29, label %30, label %32

30:                                               ; preds = %18
  %31 = load i32, ptr %10, align 4, !tbaa !9
  store i32 %31, ptr %4, align 4
  store i32 1, ptr %11, align 4
  br label %49

32:                                               ; preds = %18
  %33 = load ptr, ptr %5, align 8, !tbaa !5
  %34 = load i32, ptr %10, 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 %7, align 4, !tbaa !9
  %39 = icmp sgt i32 %37, %38
  br i1 %39, label %40, label %43

40:                                               ; preds = %32
  %41 = load i32, ptr %10, align 4, !tbaa !9
  %42 = sub nsw i32 %41, 1
  store i32 %42, ptr %9, align 4, !tbaa !9
  br label %46

43:                                               ; preds = %32
  %44 = load i32, ptr %10, align 4, !tbaa !9
  %45 = add nsw i32 %44, 1
  store i32 %45, ptr %8, align 4, !tbaa !9
  br label %46

46:                                               ; preds = %43, %40
  br label %47

47:                                               ; preds = %46
  br label %14, !llvm.loop !11

48:                                               ; preds = %14
  store i32 -1, ptr %4, align 4
  store i32 1, ptr %11, align 4
  br label %49

49:                                               ; preds = %48, %30
  call void @llvm.lifetime.end.p0(i64 4, ptr %10) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %9) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %8) #2
  %50 = load i32, ptr %4, align 4
  ret i32 %50
}

; 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 -1, 1073741824) i32 @BinarySearch(ptr nocapture noundef readonly %0, i32 noundef %1, i32 noundef %2) local_unnamed_addr #0 {
  %.not19 = icmp slt i32 %1, 1
  br i1 %.not19, label %._crit_edge, label %.lr.ph.preheader

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

.lr.ph:                                           ; preds = %.lr.ph.preheader, %11
  %.01421 = phi i32 [ %.1, %11 ], [ %4, %.lr.ph.preheader ]
  %.01520 = phi i32 [ %.116, %11 ], [ 0, %.lr.ph.preheader ]
  %5 = add nuw nsw i32 %.01421, %.01520
  %6 = lshr i32 %5, 1
  %7 = zext nneg i32 %6 to i64
  %8 = getelementptr inbounds i32, ptr %0, i64 %7
  %9 = load i32, ptr %8, align 4, !tbaa !5
  %10 = icmp eq i32 %9, %2
  br i1 %10, label %._crit_edge, label %11

11:                                               ; preds = %.lr.ph
  %12 = icmp sgt i32 %9, %2
  %13 = add nsw i32 %6, -1
  %14 = add nuw nsw i32 %6, 1
  %.116 = select i1 %12, i32 %.01520, i32 %14
  %.1 = select i1 %12, i32 %13, i32 %.01421
  %.not = icmp sgt i32 %.116, %.1
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !9

._crit_edge:                                      ; preds = %.lr.ph, %11, %3
  %.0 = phi i32 [ -1, %3 ], [ -1, %11 ], [ %6, %.lr.ph ]
  ret i32 %.0
}

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,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass