; LLVM IR from stan-dev/math :: lib/tbb_2020.3/src/tbb/queuing_mutex.ll (ZN3tbb13queuing_mutex11scoped_lock7acquireERS0_)

; 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::queuing_mutex::scoped_lock" = type { ptr, ptr, i64 }
%"class.tbb::queuing_mutex" = type { %"struct.tbb::atomic" }
%"struct.tbb::atomic" = type { %"struct.tbb::internal::atomic_impl_with_arithmetic" }
%"struct.tbb::internal::atomic_impl_with_arithmetic" = type { %"struct.tbb::internal::atomic_impl" }
%"struct.tbb::internal::atomic_impl" = type { %"struct.tbb::internal::aligned_storage" }
%"struct.tbb::internal::aligned_storage" = type { ptr }

; Function Attrs: mustprogress uwtable
define dso_local void @_ZN3tbb13queuing_mutex11scoped_lock7acquireERS0_(ptr noundef nonnull align 8 dereferenceable(24) %0, ptr noundef nonnull align 8 dereferenceable(8) %1) #0 align 2 {
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  store ptr %0, ptr %3, align 8, !tbaa !5
  store ptr %1, ptr %4, align 8, !tbaa !5
  %6 = load ptr, ptr %3, align 8
  %7 = load ptr, ptr %4, align 8, !tbaa !5
  %8 = getelementptr inbounds %"class.tbb::queuing_mutex::scoped_lock", ptr %6, i32 0, i32 0
  store ptr %7, ptr %8, align 8, !tbaa !9
  %9 = getelementptr inbounds %"class.tbb::queuing_mutex::scoped_lock", ptr %6, i32 0, i32 1
  store ptr null, ptr %9, align 8, !tbaa !12
  %10 = getelementptr inbounds %"class.tbb::queuing_mutex::scoped_lock", ptr %6, i32 0, i32 2
  store i64 0, ptr %10, align 8, !tbaa !13
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #3
  %11 = load ptr, ptr %4, align 8, !tbaa !5
  %12 = getelementptr inbounds %"class.tbb::queuing_mutex", ptr %11, i32 0, i32 0
  %13 = call noundef ptr @_ZN3tbb8internal11atomic_implIPNS_13queuing_mutex11scoped_lockEE15fetch_and_storeILNS_16memory_semanticsE2EEES4_S4_(ptr noundef nonnull align 8 dereferenceable(8) %12, ptr noundef %6)
  store ptr %13, ptr %5, align 8, !tbaa !5
  %14 = load ptr, ptr %5, align 8, !tbaa !5
  %15 = icmp ne ptr %14, null
  br i1 %15, label %16, label %20

16:                                               ; preds = %2
  %17 = load ptr, ptr %5, align 8, !tbaa !5
  %18 = getelementptr inbounds %"class.tbb::queuing_mutex::scoped_lock", ptr %17, i32 0, i32 1
  store ptr %6, ptr %18, align 8, !tbaa !12
  %19 = getelementptr inbounds %"class.tbb::queuing_mutex::scoped_lock", ptr %6, i32 0, i32 2
  call void @_ZN3tbb8internal18spin_wait_while_eqImmEEvRVKT_T0_(ptr noundef nonnull align 8 dereferenceable(8) %19, i64 noundef 0)
  br label %20

20:                                               ; preds = %16, %2
  %21 = getelementptr inbounds %"class.tbb::queuing_mutex::scoped_lock", ptr %6, i32 0, i32 2
  %22 = call noundef i64 @_ZN3tbb8internal23__TBB_load_with_acquireImEET_RVKS2_(ptr noundef nonnull align 8 dereferenceable(8) %21)
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #3
  ret void
}

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #1

; Function Attrs: mustprogress uwtable
declare dso_local noundef ptr @_ZN3tbb8internal11atomic_implIPNS_13queuing_mutex11scoped_lockEE15fetch_and_storeILNS_16memory_semanticsE2EEES4_S4_(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) #0 align 2

; Function Attrs: mustprogress uwtable
declare dso_local void @_ZN3tbb8internal18spin_wait_while_eqImmEEvRVKT_T0_(ptr noundef nonnull align 8 dereferenceable(8), i64 noundef) #0

; Function Attrs: inlinehint mustprogress uwtable
declare dso_local noundef i64 @_ZN3tbb8internal23__TBB_load_with_acquireImEET_RVKS2_(ptr noundef nonnull align 8 dereferenceable(8)) #2

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #1

attributes #0 = { 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 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { 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 #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, !6, i64 0}
!10 = !{!"_ZTSN3tbb13queuing_mutex11scoped_lockE", !6, i64 0, !6, i64 8, !11, i64 16}
!11 = !{!"long", !7, i64 0}
!12 = !{!10, !6, i64 8}
!13 = !{!10, !11, i64 16}


; 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: mustprogress uwtable
define dso_local void @_ZN3tbb13queuing_mutex11scoped_lock7acquireERS0_(ptr noundef nonnull align 8 dereferenceable(24) %0, ptr noundef nonnull align 8 dereferenceable(8) %1) local_unnamed_addr #0 align 2 {
  store ptr %1, ptr %0, align 8, !tbaa !5
  %3 = getelementptr inbounds i8, ptr %0, i64 8
  %4 = getelementptr inbounds i8, ptr %0, i64 16
  tail call void @llvm.memset.p0.i64(ptr noundef nonnull align 8 dereferenceable(16) %3, i8 0, i64 16, i1 false)
  %5 = tail call noundef ptr @_ZN3tbb8internal11atomic_implIPNS_13queuing_mutex11scoped_lockEE15fetch_and_storeILNS_16memory_semanticsE2EEES4_S4_(ptr noundef nonnull align 8 dereferenceable(8) %1, ptr noundef nonnull %0)
  %.not = icmp eq ptr %5, null
  br i1 %.not, label %8, label %6

6:                                                ; preds = %2
  %7 = getelementptr inbounds i8, ptr %5, i64 8
  store ptr %0, ptr %7, align 8, !tbaa !11
  tail call void @_ZN3tbb8internal18spin_wait_while_eqImmEEvRVKT_T0_(ptr noundef nonnull align 8 dereferenceable(8) %4, i64 noundef 0)
  br label %8

8:                                                ; preds = %6, %2
  %9 = tail call noundef i64 @_ZN3tbb8internal23__TBB_load_with_acquireImEET_RVKS2_(ptr noundef nonnull align 8 dereferenceable(8) %4)
  ret void
}

; Function Attrs: mustprogress uwtable
declare dso_local noundef ptr @_ZN3tbb8internal11atomic_implIPNS_13queuing_mutex11scoped_lockEE15fetch_and_storeILNS_16memory_semanticsE2EEES4_S4_(ptr noundef nonnull align 8 dereferenceable(8), ptr noundef) local_unnamed_addr #0 align 2

; Function Attrs: mustprogress uwtable
declare dso_local void @_ZN3tbb8internal18spin_wait_while_eqImmEEvRVKT_T0_(ptr noundef nonnull align 8 dereferenceable(8), i64 noundef) local_unnamed_addr #0

; Function Attrs: inlinehint mustprogress uwtable
declare dso_local noundef i64 @_ZN3tbb8internal23__TBB_load_with_acquireImEET_RVKS2_(ptr noundef nonnull align 8 dereferenceable(8)) local_unnamed_addr #1

; Function Attrs: nocallback nofree nounwind willreturn memory(argmem: write)
declare void @llvm.memset.p0.i64(ptr nocapture writeonly, i8, i64, i1 immarg) #2

attributes #0 = { 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 = { 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 = { nocallback nofree nounwind willreturn memory(argmem: write) }

!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 = !{!"_ZTSN3tbb13queuing_mutex11scoped_lockE", !7, i64 0, !7, i64 8, !10, i64 16}
!7 = !{!"any pointer", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C++ TBAA"}
!10 = !{!"long", !8, i64 0}
!11 = !{!6, !7, i64 8}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,MemCpyOptPass,SROAPass,TailCallElimPass