; LLVM IR from thalium/icebox :: third_party/virtualbox/src/VBox/Devices/EFI/Firmware/MdePkg/Library (InternalSyncDecrement)

; 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

declare i32 @InternalSyncCompareExchange32(ptr noundef, i32 noundef, i32 noundef) #1

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

4:                                                ; preds = %7, %1
  %5 = load ptr, ptr %2, align 8, !tbaa !5
  %6 = load volatile i32, ptr %5, align 4, !tbaa !9
  store i32 %6, ptr %3, align 4, !tbaa !9
  br label %7

7:                                                ; preds = %4
  %8 = load i32, ptr %3, align 4, !tbaa !9
  %9 = load ptr, ptr %2, align 8, !tbaa !5
  %10 = load i32, ptr %3, align 4, !tbaa !9
  %11 = load i32, ptr %3, align 4, !tbaa !9
  %12 = sub i32 %11, 1
  %13 = call i32 @InternalSyncCompareExchange32(ptr noundef %9, i32 noundef %10, i32 noundef %12)
  %14 = icmp ne i32 %8, %13
  br i1 %14, label %4, label %15, !llvm.loop !11

15:                                               ; preds = %7
  %16 = load i32, ptr %3, align 4, !tbaa !9
  %17 = sub i32 %16, 1
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #3
  ret i32 %17
}

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 = { 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 #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"

declare i32 @InternalSyncCompareExchange32(ptr noundef, i32 noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: nounwind uwtable
define dso_local noundef i32 @InternalSyncDecrement(ptr noundef %0) local_unnamed_addr #1 {
  br label %2

2:                                                ; preds = %2, %1
  %3 = load volatile i32, ptr %0, align 4, !tbaa !5
  %4 = add i32 %3, -1
  %5 = tail call i32 @InternalSyncCompareExchange32(ptr noundef nonnull %0, i32 noundef %3, i32 noundef %4) #2
  %.not = icmp eq i32 %3, %5
  br i1 %.not, label %6, label %2, !llvm.loop !9

6:                                                ; preds = %2
  ret i32 %4
}

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 = { 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 = { 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 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}


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