; LLVM IR from InsightSoftwareConsortium/ITK :: Modules/ThirdParty/MINC/src/libminc/nifti (nifti1_io)

; 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 void @nifti_swap_16bytes(i64 noundef %0, ptr noundef %1) #1 {
  %3 = alloca i64, align 8
  %4 = alloca ptr, align 8
  %5 = alloca i64, align 8
  %6 = alloca ptr, align 8
  %7 = alloca ptr, align 8
  %8 = alloca ptr, align 8
  %9 = alloca i8, align 1
  store i64 %0, ptr %3, align 8, !tbaa !5
  store ptr %1, ptr %4, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #2
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #2
  %10 = load ptr, ptr %4, align 8, !tbaa !9
  store ptr %10, ptr %6, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %7) #2
  call void @llvm.lifetime.start.p0(i64 8, ptr %8) #2
  call void @llvm.lifetime.start.p0(i64 1, ptr %9) #2
  store i64 0, ptr %5, align 8, !tbaa !5
  br label %11

11:                                               ; preds = %38, %2
  %12 = load i64, ptr %5, align 8, !tbaa !5
  %13 = load i64, ptr %3, align 8, !tbaa !5
  %14 = icmp ult i64 %12, %13
  br i1 %14, label %15, label %41

15:                                               ; preds = %11
  %16 = load ptr, ptr %6, align 8, !tbaa !9
  store ptr %16, ptr %7, align 8, !tbaa !9
  %17 = load ptr, ptr %6, align 8, !tbaa !9
  %18 = getelementptr inbounds i8, ptr %17, i64 15
  store ptr %18, ptr %8, align 8, !tbaa !9
  br label %19

19:                                               ; preds = %23, %15
  %20 = load ptr, ptr %8, align 8, !tbaa !9
  %21 = load ptr, ptr %7, align 8, !tbaa !9
  %22 = icmp ugt ptr %20, %21
  br i1 %22, label %23, label %35

23:                                               ; preds = %19
  %24 = load ptr, ptr %7, align 8, !tbaa !9
  %25 = load i8, ptr %24, align 1, !tbaa !11
  store i8 %25, ptr %9, align 1, !tbaa !11
  %26 = load ptr, ptr %8, align 8, !tbaa !9
  %27 = load i8, ptr %26, align 1, !tbaa !11
  %28 = load ptr, ptr %7, align 8, !tbaa !9
  store i8 %27, ptr %28, align 1, !tbaa !11
  %29 = load i8, ptr %9, align 1, !tbaa !11
  %30 = load ptr, ptr %8, align 8, !tbaa !9
  store i8 %29, ptr %30, align 1, !tbaa !11
  %31 = load ptr, ptr %7, align 8, !tbaa !9
  %32 = getelementptr inbounds i8, ptr %31, i32 1
  store ptr %32, ptr %7, align 8, !tbaa !9
  %33 = load ptr, ptr %8, align 8, !tbaa !9
  %34 = getelementptr inbounds i8, ptr %33, i32 -1
  store ptr %34, ptr %8, align 8, !tbaa !9
  br label %19, !llvm.loop !12

35:                                               ; preds = %19
  %36 = load ptr, ptr %6, align 8, !tbaa !9
  %37 = getelementptr inbounds i8, ptr %36, i64 16
  store ptr %37, ptr %6, align 8, !tbaa !9
  br label %38

38:                                               ; preds = %35
  %39 = load i64, ptr %5, align 8, !tbaa !5
  %40 = add i64 %39, 1
  store i64 %40, ptr %5, align 8, !tbaa !5
  br label %11, !llvm.loop !14

41:                                               ; preds = %11
  call void @llvm.lifetime.end.p0(i64 1, ptr %9) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %8) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %7) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #2
  ret void
}

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 = { 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 = !{!"long", !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 = !{!7, !7, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}
!14 = distinct !{!14, !13}


; 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 norecurse nosync nounwind memory(readwrite, inaccessiblemem: none) uwtable
define dso_local void @nifti_swap_16bytes(i64 noundef %0, ptr noundef %1) local_unnamed_addr #0 {
  %.not = icmp eq i64 %0, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph.preheader

.lr.ph.preheader:                                 ; preds = %2
  %xtraiter = and i64 %0, 1
  %3 = icmp eq i64 %0, 1
  br i1 %3, label %._crit_edge.loopexit.unr-lcssa, label %.lr.ph.preheader.new

.lr.ph.preheader.new:                             ; preds = %.lr.ph.preheader
  %unroll_iter = and i64 %0, -2
  br label %.lr.ph

.lr.ph:                                           ; preds = %19, %.lr.ph.preheader.new
  %.01720 = phi ptr [ %1, %.lr.ph.preheader.new ], [ %20, %19 ]
  %niter = phi i64 [ 0, %.lr.ph.preheader.new ], [ %niter.next.1, %19 ]
  %4 = getelementptr inbounds i8, ptr %.01720, i64 15
  br label %5

5:                                                ; preds = %.lr.ph, %5
  %.01519 = phi ptr [ %4, %.lr.ph ], [ %9, %5 ]
  %.01618 = phi ptr [ %.01720, %.lr.ph ], [ %8, %5 ]
  %6 = load i8, ptr %.01618, align 1, !tbaa !5
  %7 = load i8, ptr %.01519, align 1, !tbaa !5
  store i8 %7, ptr %.01618, align 1, !tbaa !5
  store i8 %6, ptr %.01519, align 1, !tbaa !5
  %8 = getelementptr inbounds i8, ptr %.01618, i64 1
  %9 = getelementptr inbounds i8, ptr %.01519, i64 -1
  %10 = icmp ugt ptr %9, %8
  br i1 %10, label %5, label %.lr.ph.1, !llvm.loop !8

.lr.ph.1:                                         ; preds = %5
  %11 = getelementptr inbounds i8, ptr %.01720, i64 16
  %12 = getelementptr inbounds i8, ptr %.01720, i64 31
  br label %13

13:                                               ; preds = %13, %.lr.ph.1
  %.01519.1 = phi ptr [ %12, %.lr.ph.1 ], [ %17, %13 ]
  %.01618.1 = phi ptr [ %11, %.lr.ph.1 ], [ %16, %13 ]
  %14 = load i8, ptr %.01618.1, align 1, !tbaa !5
  %15 = load i8, ptr %.01519.1, align 1, !tbaa !5
  store i8 %15, ptr %.01618.1, align 1, !tbaa !5
  store i8 %14, ptr %.01519.1, align 1, !tbaa !5
  %16 = getelementptr inbounds i8, ptr %.01618.1, i64 1
  %17 = getelementptr inbounds i8, ptr %.01519.1, i64 -1
  %18 = icmp ugt ptr %17, %16
  br i1 %18, label %13, label %19, !llvm.loop !8

19:                                               ; preds = %13
  %20 = getelementptr inbounds i8, ptr %.01720, i64 32
  %niter.next.1 = add i64 %niter, 2
  %niter.ncmp.1 = icmp eq i64 %niter.next.1, %unroll_iter
  br i1 %niter.ncmp.1, label %._crit_edge.loopexit.unr-lcssa, label %.lr.ph, !llvm.loop !10

._crit_edge.loopexit.unr-lcssa:                   ; preds = %19, %.lr.ph.preheader
  %.01720.unr = phi ptr [ %1, %.lr.ph.preheader ], [ %20, %19 ]
  %lcmp.mod.not = icmp eq i64 %xtraiter, 0
  br i1 %lcmp.mod.not, label %._crit_edge, label %.lr.ph.epil

.lr.ph.epil:                                      ; preds = %._crit_edge.loopexit.unr-lcssa
  %21 = getelementptr inbounds i8, ptr %.01720.unr, i64 15
  br label %22

22:                                               ; preds = %22, %.lr.ph.epil
  %.01519.epil = phi ptr [ %21, %.lr.ph.epil ], [ %26, %22 ]
  %.01618.epil = phi ptr [ %.01720.unr, %.lr.ph.epil ], [ %25, %22 ]
  %23 = load i8, ptr %.01618.epil, align 1, !tbaa !5
  %24 = load i8, ptr %.01519.epil, align 1, !tbaa !5
  store i8 %24, ptr %.01618.epil, align 1, !tbaa !5
  store i8 %23, ptr %.01519.epil, align 1, !tbaa !5
  %25 = getelementptr inbounds i8, ptr %.01618.epil, i64 1
  %26 = getelementptr inbounds i8, ptr %.01519.epil, i64 -1
  %27 = icmp ugt ptr %26, %25
  br i1 %27, label %22, label %._crit_edge, !llvm.loop !8

._crit_edge:                                      ; preds = %._crit_edge.loopexit.unr-lcssa, %22, %2
  ret void
}

attributes #0 = { nofree norecurse nosync nounwind memory(readwrite, inaccessiblemem: none) 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, !6, i64 0}
!6 = !{!"omnipotent char", !7, i64 0}
!7 = !{!"Simple C/C++ TBAA"}
!8 = distinct !{!8, !9}
!9 = !{!"llvm.loop.mustprogress"}
!10 = distinct !{!10, !9}


; Effective O3 passes: GlobalOptPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass