; LLVM IR from aap/pdp6 :: emu (util)

; 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 @readn(i32 noundef %0, ptr noundef %1, i32 noundef %2) #1 {
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca ptr, align 8
  %7 = alloca i32, align 4
  %8 = alloca i32, align 4
  %9 = alloca i32, align 4
  store i32 %0, ptr %5, align 4, !tbaa !5
  store ptr %1, ptr %6, align 8, !tbaa !9
  store i32 %2, ptr %7, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %8) #3
  br label %10

10:                                               ; preds = %23, %3
  %11 = load i32, ptr %7, align 4, !tbaa !5
  %12 = icmp sgt i32 %11, 0
  br i1 %12, label %13, label %31

13:                                               ; preds = %10
  %14 = load i32, ptr %5, align 4, !tbaa !5
  %15 = load ptr, ptr %6, align 8, !tbaa !9
  %16 = load i32, ptr %7, align 4, !tbaa !5
  %17 = sext i32 %16 to i64
  %18 = call i64 @read(i32 noundef %14, ptr noundef %15, i64 noundef %17)
  %19 = trunc i64 %18 to i32
  store i32 %19, ptr %8, align 4, !tbaa !5
  %20 = load i32, ptr %8, align 4, !tbaa !5
  %21 = icmp sle i32 %20, 0
  br i1 %21, label %22, label %23

22:                                               ; preds = %13
  store i32 -1, ptr %4, align 4
  store i32 1, ptr %9, align 4
  br label %32

23:                                               ; preds = %13
  %24 = load i32, ptr %8, align 4, !tbaa !5
  %25 = load ptr, ptr %6, align 8, !tbaa !9
  %26 = sext i32 %24 to i64
  %27 = getelementptr inbounds i8, ptr %25, i64 %26
  store ptr %27, ptr %6, align 8, !tbaa !9
  %28 = load i32, ptr %8, align 4, !tbaa !5
  %29 = load i32, ptr %7, align 4, !tbaa !5
  %30 = sub nsw i32 %29, %28
  store i32 %30, ptr %7, align 4, !tbaa !5
  br label %10, !llvm.loop !11

31:                                               ; preds = %10
  store i32 0, ptr %4, align 4
  store i32 1, ptr %9, align 4
  br label %32

32:                                               ; preds = %31, %22
  call void @llvm.lifetime.end.p0(i64 4, ptr %8) #3
  %33 = load i32, ptr %4, align 4
  ret i32 %33
}

declare i64 @read(i32 noundef, ptr noundef, i64 noundef) #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 = { "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/C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"any pointer", !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 nounwind uwtable
define dso_local range(i32 -1, 1) i32 @readn(i32 noundef %0, ptr nocapture noundef %1, i32 noundef %2) local_unnamed_addr #0 {
  %4 = icmp sgt i32 %2, 0
  br i1 %4, label %.lr.ph, label %._crit_edge

.lr.ph:                                           ; preds = %3, %9
  %.0913 = phi i32 [ %12, %9 ], [ %2, %3 ]
  %.01012 = phi ptr [ %11, %9 ], [ %1, %3 ]
  %5 = zext nneg i32 %.0913 to i64
  %6 = tail call i64 @read(i32 noundef %0, ptr noundef %.01012, i64 noundef %5) #2
  %7 = trunc i64 %6 to i32
  %8 = icmp slt i32 %7, 1
  br i1 %8, label %._crit_edge, label %9

9:                                                ; preds = %.lr.ph
  %10 = and i64 %6, 2147483647
  %11 = getelementptr inbounds i8, ptr %.01012, i64 %10
  %12 = sub nsw i32 %.0913, %7
  %13 = icmp sgt i32 %12, 0
  br i1 %13, label %.lr.ph, label %._crit_edge, !llvm.loop !5

._crit_edge:                                      ; preds = %.lr.ph, %9, %3
  %.0 = phi i32 [ 0, %3 ], [ 0, %9 ], [ -1, %.lr.ph ]
  ret i32 %.0
}

; Function Attrs: nofree
declare noundef i64 @read(i32 noundef, ptr nocapture noundef, i64 noundef) local_unnamed_addr #1

attributes #0 = { nofree 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 "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 = { 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 = distinct !{!5, !6}
!6 = !{!"llvm.loop.mustprogress"}


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