; LLVM IR from 6leetcode/6leetcode :: questions/Algorithms/0053. Maximum Subarray (Solution)

; 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: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

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

11:                                               ; preds = %39, %2
  %12 = load i32, ptr %7, align 4, !tbaa !9
  %13 = load i32, ptr %4, align 4, !tbaa !9
  %14 = icmp slt i32 %12, %13
  br i1 %14, label %16, label %15

15:                                               ; preds = %11
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #3
  br label %42

16:                                               ; preds = %11
  %17 = load i32, ptr %5, align 4, !tbaa !9
  %18 = load ptr, ptr %3, align 8, !tbaa !5
  %19 = load i32, ptr %7, align 4, !tbaa !9
  %20 = sext i32 %19 to i64
  %21 = getelementptr inbounds i32, ptr %18, i64 %20
  %22 = load i32, ptr %21, align 4, !tbaa !9
  %23 = add nsw i32 %17, %22
  %24 = sitofp i32 %23 to double
  %25 = load ptr, ptr %3, align 8, !tbaa !5
  %26 = load i32, ptr %7, align 4, !tbaa !9
  %27 = sext i32 %26 to i64
  %28 = getelementptr inbounds i32, ptr %25, i64 %27
  %29 = load i32, ptr %28, align 4, !tbaa !9
  %30 = sitofp i32 %29 to double
  %31 = call double @llvm.maxnum.f64(double %24, double %30)
  %32 = fptosi double %31 to i32
  store i32 %32, ptr %5, align 4, !tbaa !9
  %33 = load i32, ptr %6, align 4, !tbaa !9
  %34 = sitofp i32 %33 to double
  %35 = load i32, ptr %5, align 4, !tbaa !9
  %36 = sitofp i32 %35 to double
  %37 = call double @llvm.maxnum.f64(double %34, double %36)
  %38 = fptosi double %37 to i32
  store i32 %38, ptr %6, align 4, !tbaa !9
  br label %39

39:                                               ; preds = %16
  %40 = load i32, ptr %7, align 4, !tbaa !9
  %41 = add nsw i32 %40, 1
  store i32 %41, ptr %7, align 4, !tbaa !9
  br label %11, !llvm.loop !11

42:                                               ; preds = %15
  %43 = load i32, ptr %6, align 4, !tbaa !9
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #3
  ret i32 %43
}

; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare double @llvm.maxnum.f64(double, double) #2

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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 #2 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }
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 = !{!"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 i32 @maxSubArray(ptr nocapture noundef readonly %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = load i32, ptr %0, align 4, !tbaa !5
  %4 = icmp sgt i32 %1, 0
  br i1 %4, 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

._crit_edge:                                      ; preds = %.lr.ph, %2
  %.011.lcssa = phi i32 [ %3, %2 ], [ %15, %.lr.ph ]
  ret i32 %.011.lcssa

.lr.ph:                                           ; preds = %.lr.ph.preheader, %.lr.ph
  %indvars.iv = phi i64 [ 0, %.lr.ph.preheader ], [ %indvars.iv.next, %.lr.ph ]
  %.01114 = phi i32 [ %3, %.lr.ph.preheader ], [ %15, %.lr.ph ]
  %.01213 = phi i32 [ 0, %.lr.ph.preheader ], [ %11, %.lr.ph ]
  %5 = getelementptr inbounds i32, ptr %0, i64 %indvars.iv
  %6 = load i32, ptr %5, align 4, !tbaa !5
  %7 = add nsw i32 %6, %.01213
  %8 = sitofp i32 %7 to double
  %9 = sitofp i32 %6 to double
  %10 = tail call double @llvm.maxnum.f64(double %8, double %9)
  %11 = fptosi double %10 to i32
  %12 = sitofp i32 %.01114 to double
  %13 = sitofp i32 %11 to double
  %14 = tail call double @llvm.maxnum.f64(double %12, double %13)
  %15 = fptosi double %14 to i32
  %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, label %.lr.ph, !llvm.loop !9
}

; Function Attrs: mustprogress nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare double @llvm.maxnum.f64(double, double) #1

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" }
attributes #1 = { mustprogress nocallback nofree nosync nounwind speculatable willreturn memory(none) }

!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,GVNPass,GlobalOptPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass