; LLVM IR from DimitrisJim/leetcode_solutions :: C/Algorithms (389)

; 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 signext i8 @findTheDifference(ptr noundef %0, ptr noundef %1) #0 {
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  store ptr %1, ptr %4, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #2
  store i32 0, ptr %5, align 4, !tbaa !9
  br label %6

6:                                                ; preds = %10, %2
  %7 = load ptr, ptr %3, align 8, !tbaa !5
  %8 = load i8, ptr %7, align 1, !tbaa !11
  %9 = icmp ne i8 %8, 0
  br i1 %9, label %10, label %22

10:                                               ; preds = %6
  %11 = load ptr, ptr %3, align 8, !tbaa !5
  %12 = getelementptr inbounds i8, ptr %11, i32 1
  store ptr %12, ptr %3, align 8, !tbaa !5
  %13 = load i8, ptr %11, align 1, !tbaa !11
  %14 = sext i8 %13 to i32
  %15 = load ptr, ptr %4, align 8, !tbaa !5
  %16 = getelementptr inbounds i8, ptr %15, i32 1
  store ptr %16, ptr %4, align 8, !tbaa !5
  %17 = load i8, ptr %15, align 1, !tbaa !11
  %18 = sext i8 %17 to i32
  %19 = xor i32 %14, %18
  %20 = load i32, ptr %5, align 4, !tbaa !9
  %21 = xor i32 %20, %19
  store i32 %21, ptr %5, align 4, !tbaa !9
  br label %6, !llvm.loop !12

22:                                               ; preds = %6
  %23 = load i32, ptr %5, align 4, !tbaa !9
  %24 = load ptr, ptr %4, align 8, !tbaa !5
  %25 = load i8, ptr %24, align 1, !tbaa !11
  %26 = sext i8 %25 to i32
  %27 = xor i32 %23, %26
  %28 = trunc i32 %27 to i8
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #2
  ret i8 %28
}

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

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

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" }
attributes #1 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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 = !{!"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 signext i8 @findTheDifference(ptr nocapture noundef readonly %0, ptr nocapture noundef readonly %1) local_unnamed_addr #0 {
  %3 = load i8, ptr %0, align 1, !tbaa !5
  %.not8 = icmp eq i8 %3, 0
  br i1 %.not8, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %2, %.lr.ph
  %4 = phi i8 [ %10, %.lr.ph ], [ %3, %2 ]
  %.011 = phi i8 [ %9, %.lr.ph ], [ 0, %2 ]
  %.0510 = phi ptr [ %6, %.lr.ph ], [ %1, %2 ]
  %.069 = phi ptr [ %5, %.lr.ph ], [ %0, %2 ]
  %5 = getelementptr inbounds i8, ptr %.069, i64 1
  %6 = getelementptr inbounds i8, ptr %.0510, i64 1
  %7 = load i8, ptr %.0510, align 1, !tbaa !5
  %8 = xor i8 %4, %.011
  %9 = xor i8 %8, %7
  %10 = load i8, ptr %5, align 1, !tbaa !5
  %.not = icmp eq i8 %10, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !8

._crit_edge:                                      ; preds = %.lr.ph, %2
  %.05.lcssa = phi ptr [ %1, %2 ], [ %6, %.lr.ph ]
  %.0.lcssa = phi i8 [ 0, %2 ], [ %9, %.lr.ph ]
  %11 = load i8, ptr %.05.lcssa, align 1, !tbaa !5
  %12 = xor i8 %11, %.0.lcssa
  ret i8 %12
}

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: AggressiveInstCombinePass,EarlyCSEPass,GVNPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,JumpThreadingPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass