; LLVM IR from sunkafei/xcpc-algorithm-templates :: 算法/数学算法/三分求极值.ll (Z11maximum_intii)

; 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 uwtable
define dso_local noundef i32 @_Z11maximum_intii(i32 noundef %0, i32 noundef %1) #0 {
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  store i32 %1, ptr %4, align 4, !tbaa !5
  br label %7

7:                                                ; preds = %36, %2
  %8 = load i32, ptr %4, align 4, !tbaa !5
  %9 = load i32, ptr %3, align 4, !tbaa !5
  %10 = icmp sgt i32 %8, %9
  br i1 %10, label %11, label %37

11:                                               ; preds = %7
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #3
  %12 = load i32, ptr %3, align 4, !tbaa !5
  %13 = mul nsw i32 2, %12
  %14 = load i32, ptr %4, align 4, !tbaa !5
  %15 = add nsw i32 %13, %14
  %16 = sdiv i32 %15, 3
  store i32 %16, ptr %5, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #3
  %17 = load i32, ptr %4, align 4, !tbaa !5
  %18 = mul nsw i32 2, %17
  %19 = load i32, ptr %3, align 4, !tbaa !5
  %20 = add nsw i32 %18, %19
  %21 = add nsw i32 %20, 2
  %22 = sdiv i32 %21, 3
  store i32 %22, ptr %6, align 4, !tbaa !5
  %23 = load i32, ptr %5, align 4, !tbaa !5
  %24 = sub nsw i32 %23, 8
  %25 = call noundef double @_ZSt4fabsIiEN9__gnu_cxx11__enable_ifIXsr12__is_integerIT_EE7__valueEdE6__typeES2_(i32 noundef %24)
  %26 = load i32, ptr %6, align 4, !tbaa !5
  %27 = sub nsw i32 %26, 8
  %28 = call noundef double @_ZSt4fabsIiEN9__gnu_cxx11__enable_ifIXsr12__is_integerIT_EE7__valueEdE6__typeES2_(i32 noundef %27)
  %29 = fcmp ogt double %25, %28
  br i1 %29, label %30, label %33

30:                                               ; preds = %11
  %31 = load i32, ptr %6, align 4, !tbaa !5
  %32 = sub nsw i32 %31, 1
  store i32 %32, ptr %4, align 4, !tbaa !5
  br label %36

33:                                               ; preds = %11
  %34 = load i32, ptr %5, align 4, !tbaa !5
  %35 = add nsw i32 %34, 1
  store i32 %35, ptr %3, align 4, !tbaa !5
  br label %36

36:                                               ; preds = %33, %30
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #3
  br label %7, !llvm.loop !9

37:                                               ; preds = %7
  %38 = load i32, ptr %3, align 4, !tbaa !5
  ret i32 %38
}

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef double @_ZSt4fabsIiEN9__gnu_cxx11__enable_ifIXsr12__is_integerIT_EE7__valueEdE6__typeES2_(i32 noundef) #2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1

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" }
attributes #1 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { inlinehint 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 #3 = { 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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"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 nounwind uwtable
define dso_local noundef i32 @_Z11maximum_intii(i32 noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = icmp sgt i32 %1, %0
  br i1 %3, label %.lr.ph, label %._crit_edge

.lr.ph:                                           ; preds = %2, %.lr.ph
  %.014 = phi i32 [ %.1, %.lr.ph ], [ %0, %2 ]
  %.01113 = phi i32 [ %.112, %.lr.ph ], [ %1, %2 ]
  %4 = shl nsw i32 %.014, 1
  %5 = add nsw i32 %4, %.01113
  %6 = sdiv i32 %5, 3
  %7 = shl nsw i32 %.01113, 1
  %8 = add i32 %.014, 2
  %9 = add i32 %8, %7
  %10 = sdiv i32 %9, 3
  %11 = add nsw i32 %6, -8
  %12 = tail call noundef double @_ZSt4fabsIiEN9__gnu_cxx11__enable_ifIXsr12__is_integerIT_EE7__valueEdE6__typeES2_(i32 noundef %11)
  %13 = add nsw i32 %10, -8
  %14 = tail call noundef double @_ZSt4fabsIiEN9__gnu_cxx11__enable_ifIXsr12__is_integerIT_EE7__valueEdE6__typeES2_(i32 noundef %13)
  %15 = fcmp ogt double %12, %14
  %16 = add nsw i32 %10, -1
  %17 = add nsw i32 %6, 1
  %.112 = select i1 %15, i32 %16, i32 %.01113
  %.1 = select i1 %15, i32 %.014, i32 %17
  %18 = icmp sgt i32 %.112, %.1
  br i1 %18, label %.lr.ph, label %._crit_edge, !llvm.loop !5

._crit_edge:                                      ; preds = %.lr.ph, %2
  %.0.lcssa = phi i32 [ %0, %2 ], [ %.1, %.lr.ph ]
  ret i32 %.0.lcssa
}

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare dso_local noundef double @_ZSt4fabsIiEN9__gnu_cxx11__enable_ifIXsr12__is_integerIT_EE7__valueEdE6__typeES2_(i32 noundef) local_unnamed_addr #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 = { inlinehint 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" }

!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 = distinct !{!5, !6}
!6 = !{!"llvm.loop.mustprogress"}


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