; LLVM IR from thalium/icebox :: third_party/virtualbox/src/VBox/Devices/EFI/Firmware/MdePkg/Library (InternalMemCompareMem)

; 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 i64 @InternalMemCompareMem(ptr noundef %0, ptr noundef %1, i64 noundef %2) #0 {
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca i64, 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
  br label %7

7:                                                ; preds = %21, %3
  %8 = load i64, ptr %6, align 8, !tbaa !9
  %9 = add i64 %8, -1
  store i64 %9, ptr %6, align 8, !tbaa !9
  %10 = icmp ne i64 %9, 0
  br i1 %10, label %11, label %19

11:                                               ; preds = %7
  %12 = load ptr, ptr %4, align 8, !tbaa !5
  %13 = load i8, ptr %12, align 1, !tbaa !11
  %14 = sext i8 %13 to i32
  %15 = load ptr, ptr %5, align 8, !tbaa !5
  %16 = load i8, ptr %15, align 1, !tbaa !11
  %17 = sext i8 %16 to i32
  %18 = icmp eq i32 %14, %17
  br label %19

19:                                               ; preds = %11, %7
  %20 = phi i1 [ false, %7 ], [ %18, %11 ]
  br i1 %20, label %21, label %26

21:                                               ; preds = %19
  %22 = load ptr, ptr %4, align 8, !tbaa !5
  %23 = getelementptr inbounds i8, ptr %22, i64 1
  store ptr %23, ptr %4, align 8, !tbaa !5
  %24 = load ptr, ptr %5, align 8, !tbaa !5
  %25 = getelementptr inbounds i8, ptr %24, i64 1
  store ptr %25, ptr %5, align 8, !tbaa !5
  br label %7, !llvm.loop !12

26:                                               ; preds = %19
  %27 = load ptr, ptr %4, align 8, !tbaa !5
  %28 = load i8, ptr %27, align 1, !tbaa !11
  %29 = zext i8 %28 to i64
  %30 = load ptr, ptr %5, align 8, !tbaa !5
  %31 = load i8, ptr %30, align 1, !tbaa !11
  %32 = zext i8 %31 to i64
  %33 = sub nsw i64 %29, %32
  ret i64 %33
}

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 = !{!"long 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(read, inaccessiblemem: none) uwtable
define dso_local range(i64 -255, 256) i64 @InternalMemCompareMem(ptr nocapture noundef readonly %0, ptr nocapture noundef readonly %1, i64 noundef %2) local_unnamed_addr #0 {
  %4 = add i64 %2, -1
  %.not9 = icmp eq i64 %4, 0
  br i1 %.not9, label %.critedge, label %.lr.ph.preheader

.lr.ph.preheader:                                 ; preds = %3
  %scevgep = getelementptr i8, ptr %0, i64 %4
  %scevgep16 = getelementptr i8, ptr %1, i64 %4
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.preheader, %9
  %5 = phi i64 [ %12, %9 ], [ %4, %.lr.ph.preheader ]
  %.0611 = phi ptr [ %11, %9 ], [ %1, %.lr.ph.preheader ]
  %.0710 = phi ptr [ %10, %9 ], [ %0, %.lr.ph.preheader ]
  %6 = load i8, ptr %.0710, align 1, !tbaa !5
  %7 = load i8, ptr %.0611, align 1, !tbaa !5
  %8 = icmp eq i8 %6, %7
  br i1 %8, label %9, label %.critedge

9:                                                ; preds = %.lr.ph
  %10 = getelementptr inbounds i8, ptr %.0710, i64 1
  %11 = getelementptr inbounds i8, ptr %.0611, i64 1
  %12 = add i64 %5, -1
  %.not = icmp eq i64 %12, 0
  br i1 %.not, label %.critedge, label %.lr.ph, !llvm.loop !8

.critedge:                                        ; preds = %.lr.ph, %9, %3
  %.07.lcssa = phi ptr [ %0, %3 ], [ %scevgep, %9 ], [ %.0710, %.lr.ph ]
  %.06.lcssa = phi ptr [ %1, %3 ], [ %scevgep16, %9 ], [ %.0611, %.lr.ph ]
  %13 = load i8, ptr %.07.lcssa, align 1, !tbaa !5
  %14 = zext i8 %13 to i64
  %15 = load i8, ptr %.06.lcssa, align 1, !tbaa !5
  %16 = zext i8 %15 to i64
  %17 = sub nsw i64 %14, %16
  ret i64 %17
}

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,IndVarSimplifyPass,InstCombinePass,JumpThreadingPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass