; LLVM IR from VastoLorde95/Competitive-Programming :: Hackerrank/Week of Code/Week 25/Problem G/G.ll (Z5shiftv)

; 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"

@n = external dso_local global i32, align 4
@b = external dso_local global [100100 x i32], align 16

; Function Attrs: mustprogress nounwind uwtable
define dso_local void @_Z5shiftv() #0 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  call void @llvm.lifetime.start.p0(i64 4, ptr %1) #2
  %3 = load i32, ptr @b, align 16, !tbaa !5
  store i32 %3, ptr %1, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #2
  store i32 1, ptr %2, align 4, !tbaa !5
  br label %4

4:                                                ; preds = %18, %0
  %5 = load i32, ptr %2, align 4, !tbaa !5
  %6 = load i32, ptr @n, align 4, !tbaa !5
  %7 = icmp slt i32 %5, %6
  br i1 %7, label %9, label %8

8:                                                ; preds = %4
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #2
  br label %21

9:                                                ; preds = %4
  %10 = load i32, ptr %2, align 4, !tbaa !5
  %11 = sext i32 %10 to i64
  %12 = getelementptr inbounds [100100 x i32], ptr @b, i64 0, i64 %11
  %13 = load i32, ptr %12, align 4, !tbaa !5
  %14 = load i32, ptr %2, align 4, !tbaa !5
  %15 = sub nsw i32 %14, 1
  %16 = sext i32 %15 to i64
  %17 = getelementptr inbounds [100100 x i32], ptr @b, i64 0, i64 %16
  store i32 %13, ptr %17, align 4, !tbaa !5
  br label %18

18:                                               ; preds = %9
  %19 = load i32, ptr %2, align 4, !tbaa !5
  %20 = add nsw i32 %19, 1
  store i32 %20, ptr %2, align 4, !tbaa !5
  br label %4, !llvm.loop !9

21:                                               ; preds = %8
  %22 = load i32, ptr %1, align 4, !tbaa !5
  %23 = load i32, ptr @n, align 4, !tbaa !5
  %24 = sub nsw i32 %23, 1
  %25 = sext i32 %24 to i64
  %26 = getelementptr inbounds [100100 x i32], ptr @b, i64 0, i64 %25
  store i32 %22, ptr %26, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr %1) #2
  ret void
}

; 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 = !{!"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"

@n = external dso_local local_unnamed_addr global i32, align 4
@b = external dso_local local_unnamed_addr global [100100 x i32], align 16

; Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(readwrite, argmem: none, inaccessiblemem: none) uwtable
define dso_local void @_Z5shiftv() local_unnamed_addr #0 {
  %1 = load i32, ptr @b, align 16, !tbaa !5
  %2 = load i32, ptr @n, align 4, !tbaa !5
  %3 = icmp sgt i32 %2, 1
  %4 = add nsw i32 %2, -1
  br i1 %3, label %.lr.ph.preheader, label %._crit_edge

.lr.ph.preheader:                                 ; preds = %0
  %5 = zext nneg i32 %4 to i64
  %6 = shl nuw nsw i64 %5, 2
  tail call void @llvm.memmove.p0.p0.i64(ptr nonnull align 16 @b, ptr nonnull align 4 getelementptr inbounds (i8, ptr @b, i64 4), i64 %6, i1 false), !tbaa !5
  br label %._crit_edge

._crit_edge:                                      ; preds = %0, %.lr.ph.preheader
  %7 = sext i32 %4 to i64
  %8 = getelementptr inbounds [100100 x i32], ptr @b, i64 0, i64 %7
  store i32 %1, ptr %8, align 4, !tbaa !5
  ret void
}

; Function Attrs: nocallback nofree nounwind willreturn memory(argmem: readwrite)
declare void @llvm.memmove.p0.p0.i64(ptr nocapture writeonly, ptr nocapture readonly, i64, i1 immarg) #1

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(readwrite, argmem: none, inaccessiblemem: none) 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 nounwind willreturn memory(argmem: readwrite) }

!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"}


; Effective O3 passes: CorrelatedValuePropagationPass,EarlyCSEPass,GVNPass,GlobalOptPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,LCSSAPass,LICMPass,LoopIdiomRecognizePass,LoopRotatePass,LoopSimplifyPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass