; LLVM IR from google/esh :: shell/lib/string (string)

; 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 ptr @memcpy(ptr noundef %0, ptr noundef %1, i64 noundef %2) #1 {
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca i64, align 8
  %7 = alloca i64, align 8
  %8 = alloca ptr, align 8
  %9 = alloca ptr, align 8
  store ptr %0, ptr %4, align 8, !tbaa !5
  store ptr %1, ptr %5, align 8, !tbaa !5
  store i64 %2, 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
  %10 = load ptr, ptr %5, align 8, !tbaa !5
  store ptr %10, ptr %8, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %9) #2
  %11 = load ptr, ptr %4, align 8, !tbaa !5
  store ptr %11, ptr %9, align 8, !tbaa !5
  store i64 0, ptr %7, align 8, !tbaa !9
  br label %12

12:                                               ; preds = %24, %3
  %13 = load i64, ptr %7, align 8, !tbaa !9
  %14 = load i64, ptr %6, align 8, !tbaa !9
  %15 = icmp ult i64 %13, %14
  br i1 %15, label %16, label %27

16:                                               ; preds = %12
  %17 = load ptr, ptr %8, align 8, !tbaa !5
  %18 = load i64, ptr %7, align 8, !tbaa !9
  %19 = getelementptr inbounds i8, ptr %17, i64 %18
  %20 = load i8, ptr %19, align 1, !tbaa !11
  %21 = load ptr, ptr %9, align 8, !tbaa !5
  %22 = load i64, ptr %7, align 8, !tbaa !9
  %23 = getelementptr inbounds i8, ptr %21, i64 %22
  store i8 %20, ptr %23, align 1, !tbaa !11
  br label %24

24:                                               ; preds = %16
  %25 = load i64, ptr %7, align 8, !tbaa !9
  %26 = add i64 %25, 1
  store i64 %26, ptr %7, align 8, !tbaa !9
  br label %12, !llvm.loop !12

27:                                               ; preds = %12
  call void @llvm.lifetime.end.p0(i64 8, 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
  ret ptr null
}

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 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"long", !7, i64 0}
!11 = !{!7, !7, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"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: nofree norecurse nosync nounwind memory(argmem: readwrite) uwtable
define dso_local noalias noundef ptr @memcpy(ptr nocapture noundef writeonly %0, ptr nocapture noundef readonly %1, i64 noundef %2) local_unnamed_addr #0 {
  %.not = icmp eq i64 %2, 0
  br i1 %.not, label %._crit_edge, label %iter.check

iter.check:                                       ; preds = %3
  %4 = ptrtoint ptr %0 to i64
  %5 = ptrtoint ptr %1 to i64
  %min.iters.check = icmp ult i64 %2, 8
  %6 = sub i64 %4, %5
  %diff.check = icmp ult i64 %6, 32
  %or.cond = or i1 %min.iters.check, %diff.check
  br i1 %or.cond, label %.lr.ph.preheader, label %vector.main.loop.iter.check

vector.main.loop.iter.check:                      ; preds = %iter.check
  %min.iters.check9 = icmp ult i64 %2, 32
  br i1 %min.iters.check9, label %vec.epilog.ph, label %vector.ph

vector.ph:                                        ; preds = %vector.main.loop.iter.check
  %n.vec = and i64 %2, -32
  br label %vector.body

vector.body:                                      ; preds = %vector.body, %vector.ph
  %index = phi i64 [ 0, %vector.ph ], [ %index.next, %vector.body ]
  %7 = getelementptr inbounds i8, ptr %1, i64 %index
  %8 = getelementptr inbounds i8, ptr %7, i64 16
  %wide.load = load <16 x i8>, ptr %7, align 1, !tbaa !5
  %wide.load10 = load <16 x i8>, ptr %8, align 1, !tbaa !5
  %9 = getelementptr inbounds i8, ptr %0, i64 %index
  %10 = getelementptr inbounds i8, ptr %9, i64 16
  store <16 x i8> %wide.load, ptr %9, align 1, !tbaa !5
  store <16 x i8> %wide.load10, ptr %10, align 1, !tbaa !5
  %index.next = add nuw i64 %index, 32
  %11 = icmp eq i64 %index.next, %n.vec
  br i1 %11, label %middle.block, label %vector.body, !llvm.loop !8

middle.block:                                     ; preds = %vector.body
  %cmp.n = icmp eq i64 %n.vec, %2
  br i1 %cmp.n, label %._crit_edge, label %vec.epilog.iter.check

vec.epilog.iter.check:                            ; preds = %middle.block
  %n.vec.remaining = and i64 %2, 24
  %min.epilog.iters.check = icmp eq i64 %n.vec.remaining, 0
  br i1 %min.epilog.iters.check, label %.lr.ph.preheader, label %vec.epilog.ph

vec.epilog.ph:                                    ; preds = %vector.main.loop.iter.check, %vec.epilog.iter.check
  %vec.epilog.resume.val = phi i64 [ %n.vec, %vec.epilog.iter.check ], [ 0, %vector.main.loop.iter.check ]
  %n.vec12 = and i64 %2, -8
  br label %vec.epilog.vector.body

vec.epilog.vector.body:                           ; preds = %vec.epilog.vector.body, %vec.epilog.ph
  %index13 = phi i64 [ %vec.epilog.resume.val, %vec.epilog.ph ], [ %index.next15, %vec.epilog.vector.body ]
  %12 = getelementptr inbounds i8, ptr %1, i64 %index13
  %wide.load14 = load <8 x i8>, ptr %12, align 1, !tbaa !5
  %13 = getelementptr inbounds i8, ptr %0, i64 %index13
  store <8 x i8> %wide.load14, ptr %13, align 1, !tbaa !5
  %index.next15 = add nuw i64 %index13, 8
  %14 = icmp eq i64 %index.next15, %n.vec12
  br i1 %14, label %vec.epilog.middle.block, label %vec.epilog.vector.body, !llvm.loop !12

vec.epilog.middle.block:                          ; preds = %vec.epilog.vector.body
  %cmp.n16 = icmp eq i64 %n.vec12, %2
  br i1 %cmp.n16, label %._crit_edge, label %.lr.ph.preheader

.lr.ph.preheader:                                 ; preds = %vec.epilog.middle.block, %iter.check, %vec.epilog.iter.check
  %.08.ph = phi i64 [ 0, %iter.check ], [ %n.vec, %vec.epilog.iter.check ], [ %n.vec12, %vec.epilog.middle.block ]
  %xtraiter = and i64 %2, 3
  %lcmp.mod.not = icmp eq i64 %xtraiter, 0
  br i1 %lcmp.mod.not, label %.lr.ph.prol.loopexit, label %.lr.ph.prol

.lr.ph.prol:                                      ; preds = %.lr.ph.preheader, %.lr.ph.prol
  %.08.prol = phi i64 [ %18, %.lr.ph.prol ], [ %.08.ph, %.lr.ph.preheader ]
  %prol.iter = phi i64 [ %prol.iter.next, %.lr.ph.prol ], [ 0, %.lr.ph.preheader ]
  %15 = getelementptr inbounds i8, ptr %1, i64 %.08.prol
  %16 = load i8, ptr %15, align 1, !tbaa !5
  %17 = getelementptr inbounds i8, ptr %0, i64 %.08.prol
  store i8 %16, ptr %17, align 1, !tbaa !5
  %18 = add nuw i64 %.08.prol, 1
  %prol.iter.next = add i64 %prol.iter, 1
  %prol.iter.cmp.not = icmp eq i64 %prol.iter.next, %xtraiter
  br i1 %prol.iter.cmp.not, label %.lr.ph.prol.loopexit, label %.lr.ph.prol, !llvm.loop !13

.lr.ph.prol.loopexit:                             ; preds = %.lr.ph.prol, %.lr.ph.preheader
  %.08.unr = phi i64 [ %.08.ph, %.lr.ph.preheader ], [ %18, %.lr.ph.prol ]
  %19 = sub i64 %.08.ph, %2
  %20 = icmp ugt i64 %19, -4
  br i1 %20, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.prol.loopexit, %.lr.ph
  %.08 = phi i64 [ %36, %.lr.ph ], [ %.08.unr, %.lr.ph.prol.loopexit ]
  %21 = getelementptr inbounds i8, ptr %1, i64 %.08
  %22 = load i8, ptr %21, align 1, !tbaa !5
  %23 = getelementptr inbounds i8, ptr %0, i64 %.08
  store i8 %22, ptr %23, align 1, !tbaa !5
  %24 = add nuw i64 %.08, 1
  %25 = getelementptr inbounds i8, ptr %1, i64 %24
  %26 = load i8, ptr %25, align 1, !tbaa !5
  %27 = getelementptr inbounds i8, ptr %0, i64 %24
  store i8 %26, ptr %27, align 1, !tbaa !5
  %28 = add nuw i64 %.08, 2
  %29 = getelementptr inbounds i8, ptr %1, i64 %28
  %30 = load i8, ptr %29, align 1, !tbaa !5
  %31 = getelementptr inbounds i8, ptr %0, i64 %28
  store i8 %30, ptr %31, align 1, !tbaa !5
  %32 = add nuw i64 %.08, 3
  %33 = getelementptr inbounds i8, ptr %1, i64 %32
  %34 = load i8, ptr %33, align 1, !tbaa !5
  %35 = getelementptr inbounds i8, ptr %0, i64 %32
  store i8 %34, ptr %35, align 1, !tbaa !5
  %36 = add nuw i64 %.08, 4
  %exitcond.not.3 = icmp eq i64 %36, %2
  br i1 %exitcond.not.3, label %._crit_edge, label %.lr.ph, !llvm.loop !15

._crit_edge:                                      ; preds = %.lr.ph.prol.loopexit, %.lr.ph, %middle.block, %vec.epilog.middle.block, %3
  ret ptr null
}

attributes #0 = { nofree norecurse nosync nounwind memory(argmem: readwrite) 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, !10, !11}
!9 = !{!"llvm.loop.mustprogress"}
!10 = !{!"llvm.loop.isvectorized", i32 1}
!11 = !{!"llvm.loop.unroll.runtime.disable"}
!12 = distinct !{!12, !9, !10, !11}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.unroll.disable"}
!15 = distinct !{!15, !9, !10}


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