; LLVM IR from tangjz/acm-icpc :: self_training/2014-12-07 (E)

; 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"

@p = external dso_local global i64, align 8
@q = external dso_local global i64, align 8
@.str = external hidden unnamed_addr constant [9 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [6 x i8], align 1

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() #0 {
  %1 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  br label %2

2:                                                ; preds = %12, %0
  %3 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str, ptr noundef @p, ptr noundef @q)
  %4 = icmp eq i32 %3, 2
  br i1 %4, label %5, label %23

5:                                                ; preds = %2
  %6 = load i64, ptr @p, align 8, !tbaa !5
  %7 = load i64, ptr @q, align 8, !tbaa !5
  %8 = icmp eq i64 %6, %7
  br i1 %8, label %9, label %12

9:                                                ; preds = %5
  %10 = load i64, ptr @p, align 8, !tbaa !5
  %11 = add nsw i64 %10, 2
  store i64 %11, ptr @p, align 8, !tbaa !5
  br label %12

12:                                               ; preds = %9, %5
  %13 = load i64, ptr @p, align 8, !tbaa !5
  %14 = sub nsw i64 %13, 1
  %15 = ashr i64 %14, 1
  store i64 %15, ptr @p, align 8, !tbaa !5
  %16 = load i64, ptr @q, align 8, !tbaa !5
  %17 = sub nsw i64 %16, 1
  %18 = ashr i64 %17, 1
  store i64 %18, ptr @q, align 8, !tbaa !5
  %19 = load i64, ptr @p, align 8, !tbaa !5
  %20 = load i64, ptr @q, align 8, !tbaa !5
  %21 = mul nsw i64 %19, %20
  %22 = call i32 (ptr, ...) @printf(ptr noundef @.str.1, i64 noundef %21)
  br label %2, !llvm.loop !9

23:                                               ; preds = %2
  ret i32 0
}

declare i32 @__isoc99_scanf(ptr noundef, ...) #1

declare i32 @printf(ptr noundef, ...) #1

attributes #0 = { mustprogress norecurse 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 = { "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 = !{!"long long", !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"

@p = external dso_local global i64, align 8
@q = external dso_local global i64, align 8
@.str = external hidden unnamed_addr constant [9 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [6 x i8], align 1

; Function Attrs: mustprogress nofree norecurse nounwind uwtable
define dso_local noundef i32 @main() local_unnamed_addr #0 {
  %1 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull @p, ptr noundef nonnull @q)
  %2 = icmp eq i32 %1, 2
  br i1 %2, label %.lr.ph, label %._crit_edge

.lr.ph:                                           ; preds = %0, %.lr.ph
  %3 = load i64, ptr @p, align 8, !tbaa !5
  %4 = load i64, ptr @q, align 8, !tbaa !5
  %5 = icmp eq i64 %3, %4
  %6 = add nsw i64 %3, 2
  %spec.select = select i1 %5, i64 %6, i64 %3
  %7 = add nsw i64 %spec.select, -1
  %8 = ashr i64 %7, 1
  store i64 %8, ptr @p, align 8, !tbaa !5
  %9 = add nsw i64 %4, -1
  %10 = ashr i64 %9, 1
  store i64 %10, ptr @q, align 8, !tbaa !5
  %11 = mul nsw i64 %8, %10
  %12 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.1, i64 noundef %11)
  %13 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull @p, ptr noundef nonnull @q)
  %14 = icmp eq i32 %13, 2
  br i1 %14, label %.lr.ph, label %._crit_edge, !llvm.loop !9

._crit_edge:                                      ; preds = %.lr.ph, %0
  ret i32 0
}

; Function Attrs: nofree nounwind
declare noundef i32 @__isoc99_scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #1

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #1

attributes #0 = { mustprogress nofree norecurse 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 = { nofree nounwind "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 = !{!"long long", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: DSEPass,EarlyCSEPass,GVNPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass