; LLVM IR from stan-dev/math :: lib/tbb_2020.3/src/old (spin_rw_mutex_v2)

; 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.tbb::spin_rw_mutex" = type { i64 }

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: inlinehint mustprogress uwtable
declare hidden noundef zeroext i1 @_ZN3tbbL3CASERVmmm(ptr noundef nonnull align 8 dereferenceable(8), i64 noundef, i64 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: mustprogress uwtable
define dso_local noundef zeroext i1 @_ZN3tbb13spin_rw_mutex27internal_try_acquire_readerEPS0_(ptr noundef %0) #2 align 2 {
  %2 = alloca i1, align 1
  %3 = alloca ptr, align 8
  %4 = alloca i64, align 8
  %5 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #3
  %6 = load ptr, ptr %3, align 8, !tbaa !5
  %7 = getelementptr inbounds %"class.tbb::spin_rw_mutex", ptr %6, i32 0, i32 0
  %8 = load volatile i64, ptr %7, align 8, !tbaa !9
  store i64 %8, ptr %4, align 8, !tbaa !12
  br label %9

9:                                                ; preds = %22, %1
  %10 = load i64, ptr %4, align 8, !tbaa !12
  %11 = and i64 %10, 3
  %12 = icmp ne i64 %11, 0
  %13 = xor i1 %12, true
  br i1 %13, label %14, label %23

14:                                               ; preds = %9
  %15 = load ptr, ptr %3, align 8, !tbaa !5
  %16 = getelementptr inbounds %"class.tbb::spin_rw_mutex", ptr %15, i32 0, i32 0
  %17 = load i64, ptr %4, align 8, !tbaa !12
  %18 = add i64 %17, 4
  %19 = load i64, ptr %4, align 8, !tbaa !12
  %20 = call noundef zeroext i1 @_ZN3tbbL3CASERVmmm(ptr noundef nonnull align 8 dereferenceable(8) %16, i64 noundef %18, i64 noundef %19)
  br i1 %20, label %21, label %22

21:                                               ; preds = %14
  store i1 true, ptr %2, align 1
  store i32 1, ptr %5, align 4
  br label %24

22:                                               ; preds = %14
  br label %9, !llvm.loop !13

23:                                               ; preds = %9
  store i1 false, ptr %2, align 1
  store i32 1, ptr %5, align 4
  br label %24

24:                                               ; preds = %23, %21
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #3
  %25 = load i1, ptr %2, align 1
  ret i1 %25
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { inlinehint 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 = { 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, !11, i64 0}
!10 = !{!"_ZTSN3tbb13spin_rw_mutexE", !11, i64 0}
!11 = !{!"long", !7, i64 0}
!12 = !{!11, !11, i64 0}
!13 = distinct !{!13, !14}
!14 = !{!"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: inlinehint mustprogress uwtable
declare hidden noundef zeroext i1 @_ZN3tbbL3CASERVmmm(ptr noundef nonnull align 8 dereferenceable(8), i64 noundef, i64 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress uwtable
define dso_local noundef zeroext i1 @_ZN3tbb13spin_rw_mutex27internal_try_acquire_readerEPS0_(ptr noundef %0) local_unnamed_addr #1 align 2 {
  %2 = load volatile i64, ptr %0, align 8, !tbaa !5
  %3 = and i64 %2, 3
  %.not = icmp eq i64 %3, 0
  %4 = add i64 %2, 4
  br i1 %.not, label %.split, label %.split5

.split:                                           ; preds = %1, %.split
  %5 = tail call noundef zeroext i1 @_ZN3tbbL3CASERVmmm(ptr noundef nonnull align 8 dereferenceable(8) %0, i64 noundef %4, i64 noundef %2)
  br i1 %5, label %.split5, label %.split, !llvm.loop !10

.split5:                                          ; preds = %.split, %1
  ret i1 %.not
}

attributes #0 = { inlinehint 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 #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" }

!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, !7, i64 0}
!6 = !{!"_ZTSN3tbb13spin_rw_mutexE", !7, i64 0}
!7 = !{!"long", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C++ TBAA"}
!10 = distinct !{!10, !11}
!11 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LCSSAPass,LICMPass,LoopSimplifyCFGPass,LoopSimplifyPass,LoopUnrollPass,SROAPass,SimplifyCFGPass,TailCallElimPass