; LLVM IR from xing1357/SimpleOS :: src (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: nounwind uwtable
define dso_local i32 @memcmp(ptr noundef %0, ptr noundef %1, i32 noundef %2) #0 {
  %4 = alloca i32, align 4
  %5 = alloca ptr, align 8
  %6 = alloca ptr, align 8
  %7 = alloca i32, align 4
  store ptr %0, ptr %5, align 8, !tbaa !5
  store ptr %1, ptr %6, align 8, !tbaa !5
  store i32 %2, ptr %7, align 4, !tbaa !9
  br label %8

8:                                                ; preds = %21, %3
  %9 = load i32, ptr %7, align 4, !tbaa !9
  %10 = add i32 %9, -1
  store i32 %10, ptr %7, align 4, !tbaa !9
  %11 = icmp ne i32 %9, 0
  br i1 %11, label %12, label %26

12:                                               ; preds = %8
  %13 = load ptr, ptr %5, align 8, !tbaa !5
  %14 = load i8, ptr %13, align 1, !tbaa !11
  %15 = zext i8 %14 to i32
  %16 = load ptr, ptr %6, align 8, !tbaa !5
  %17 = load i8, ptr %16, align 1, !tbaa !11
  %18 = zext i8 %17 to i32
  %19 = icmp ne i32 %15, %18
  br i1 %19, label %20, label %21

20:                                               ; preds = %12
  store i32 0, ptr %4, align 4
  br label %27

21:                                               ; preds = %12
  %22 = load ptr, ptr %5, align 8, !tbaa !5
  %23 = getelementptr inbounds i8, ptr %22, i32 1
  store ptr %23, ptr %5, align 8, !tbaa !5
  %24 = load ptr, ptr %6, align 8, !tbaa !5
  %25 = getelementptr inbounds i8, ptr %24, i32 1
  store ptr %25, ptr %6, align 8, !tbaa !5
  br label %8, !llvm.loop !12

26:                                               ; preds = %8
  store i32 1, ptr %4, align 4
  br label %27

27:                                               ; preds = %26, %20
  %28 = load i32, ptr %4, align 4
  ret i32 %28
}

attributes #0 = { 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" }

!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 = !{!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(read, inaccessiblemem: none) uwtable
define dso_local range(i32 0, 2) i32 @memcmp(ptr nocapture noundef readonly %0, ptr nocapture noundef readonly %1, i32 noundef %2) local_unnamed_addr #0 {
  %.not9 = icmp eq i32 %2, 0
  br i1 %.not9, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %3, %6
  %.in = phi i32 [ %7, %6 ], [ %2, %3 ]
  %.0511 = phi ptr [ %9, %6 ], [ %1, %3 ]
  %.0610 = phi ptr [ %8, %6 ], [ %0, %3 ]
  %4 = load i8, ptr %.0610, align 1, !tbaa !5
  %5 = load i8, ptr %.0511, align 1, !tbaa !5
  %.not8 = icmp eq i8 %4, %5
  br i1 %.not8, label %6, label %._crit_edge

6:                                                ; preds = %.lr.ph
  %7 = add i32 %.in, -1
  %8 = getelementptr inbounds i8, ptr %.0610, i64 1
  %9 = getelementptr inbounds i8, ptr %.0511, i64 1
  %.not = icmp eq i32 %7, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !8

._crit_edge:                                      ; preds = %.lr.ph, %6, %3
  %.07 = phi i32 [ 1, %3 ], [ 1, %6 ], [ 0, %.lr.ph ]
  ret i32 %.07
}

attributes #0 = { nofree norecurse nosync nounwind memory(read, 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"}


; Effective O3 passes: GlobalOptPass,IPSCCPPass,InstCombinePass,JumpThreadingPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass