; LLVM IR from wichue/nethello :: src/event/PipeWrap.ll (ZN3chw8PipeWrap4readEPvi)

; 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"

%"class.chw::PipeWrap" = type { [2 x i32] }

; 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

declare noundef i32 @_ZN3chw12get_uv_errorEb(i1 noundef zeroext) #1

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_ZN3chw8PipeWrap4readEPvi(ptr noundef nonnull align 4 dereferenceable(8) %0, ptr noundef %1, i32 noundef %2) #2 align 2 {
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store ptr %0, ptr %4, align 8, !tbaa !5
  store ptr %1, ptr %5, align 8, !tbaa !5
  store i32 %2, ptr %6, align 4, !tbaa !9
  %8 = load ptr, ptr %4, align 8
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #3
  br label %9

9:                                                ; preds = %24, %3
  %10 = getelementptr inbounds %"class.chw::PipeWrap", ptr %8, i32 0, i32 0
  %11 = getelementptr inbounds [2 x i32], ptr %10, i64 0, i64 0
  %12 = load i32, ptr %11, align 4, !tbaa !9
  %13 = load ptr, ptr %5, align 8, !tbaa !5
  %14 = load i32, ptr %6, align 4, !tbaa !9
  %15 = sext i32 %14 to i64
  %16 = call i64 @read(i32 noundef %12, ptr noundef %13, i64 noundef %15)
  %17 = trunc i64 %16 to i32
  store i32 %17, ptr %7, align 4, !tbaa !9
  br label %18

18:                                               ; preds = %9
  %19 = load i32, ptr %7, align 4, !tbaa !9
  %20 = icmp eq i32 -1, %19
  br i1 %20, label %21, label %24

21:                                               ; preds = %18
  %22 = call noundef i32 @_ZN3chw12get_uv_errorEb(i1 noundef zeroext true)
  %23 = icmp eq i32 -4, %22
  br label %24

24:                                               ; preds = %21, %18
  %25 = phi i1 [ false, %18 ], [ %23, %21 ]
  br i1 %25, label %9, label %26, !llvm.loop !11

26:                                               ; preds = %24
  %27 = load i32, ptr %7, align 4, !tbaa !9
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #3
  ret i32 %27
}

declare i64 @read(i32 noundef, ptr noundef, i64 noundef) #1

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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" }
attributes #2 = { 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 #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++ 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"

declare noundef i32 @_ZN3chw12get_uv_errorEb(i1 noundef zeroext) local_unnamed_addr #0

; Function Attrs: mustprogress uwtable
define dso_local noundef i32 @_ZN3chw8PipeWrap4readEPvi(ptr nocapture noundef nonnull readonly align 4 dereferenceable(8) %0, ptr nocapture noundef %1, i32 noundef %2) local_unnamed_addr #1 align 2 {
  %4 = sext i32 %2 to i64
  br label %5

5:                                                ; preds = %10, %3
  %6 = load i32, ptr %0, align 4, !tbaa !5
  %7 = tail call i64 @read(i32 noundef %6, ptr noundef %1, i64 noundef %4)
  %8 = trunc i64 %7 to i32
  %9 = icmp eq i32 %8, -1
  br i1 %9, label %10, label %.critedge

10:                                               ; preds = %5
  %11 = tail call noundef i32 @_ZN3chw12get_uv_errorEb(i1 noundef zeroext true)
  %12 = icmp eq i32 %11, -4
  br i1 %12, label %5, label %.critedge, !llvm.loop !9

.critedge:                                        ; preds = %5, %10
  ret i32 %8
}

; Function Attrs: nofree
declare noundef i64 @read(i32 noundef, ptr nocapture noundef, i64 noundef) local_unnamed_addr #2

attributes #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 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 = { 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" }

!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"}


; Effective O3 passes: CorrelatedValuePropagationPass,EarlyCSEPass,GVNPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,LCSSAPass,LICMPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass