; LLVM IR from kaynewbie/algorithm :: algorithm/CodingInterviews (linked-list)

; 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"

%struct.ListNode = type { i32, ptr }

; 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 zeroext i1 @findFirst(ptr noundef %0, i32 noundef %1) #1 {
  %3 = alloca i1, align 1
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  %6 = alloca ptr, align 8
  %7 = alloca i32, align 4
  store ptr %0, ptr %4, align 8, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #2
  %8 = load ptr, ptr %4, align 8, !tbaa !5
  store ptr %8, ptr %6, align 8, !tbaa !5
  br label %9

9:                                                ; preds = %19, %2
  %10 = load ptr, ptr %6, align 8, !tbaa !5
  %11 = icmp ne ptr %10, null
  br i1 %11, label %12, label %23

12:                                               ; preds = %9
  %13 = load ptr, ptr %6, align 8, !tbaa !5
  %14 = getelementptr inbounds %struct.ListNode, ptr %13, i32 0, i32 0
  %15 = load i32, ptr %14, align 8, !tbaa !11
  %16 = load i32, ptr %5, align 4, !tbaa !9
  %17 = icmp eq i32 %15, %16
  br i1 %17, label %18, label %19

18:                                               ; preds = %12
  store i1 true, ptr %3, align 1
  store i32 1, ptr %7, align 4
  br label %24

19:                                               ; preds = %12
  %20 = load ptr, ptr %6, align 8, !tbaa !5
  %21 = getelementptr inbounds %struct.ListNode, ptr %20, i32 0, i32 1
  %22 = load ptr, ptr %21, align 8, !tbaa !13
  store ptr %22, ptr %6, align 8, !tbaa !5
  br label %9, !llvm.loop !14

23:                                               ; preds = %9
  store i1 false, ptr %3, align 1
  store i32 1, ptr %7, align 4
  br label %24

24:                                               ; preds = %23, %18
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #2
  %25 = load i1, ptr %3, align 1
  ret i1 %25
}

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 = !{!"int", !7, i64 0}
!11 = !{!12, !10, i64 0}
!12 = !{!"ListNode", !10, i64 0, !6, i64 8}
!13 = !{!12, !6, i64 8}
!14 = distinct !{!14, !15}
!15 = !{!"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 noundef zeroext i1 @findFirst(ptr noundef readonly %0, i32 noundef %1) local_unnamed_addr #0 {
  %.not6.not = icmp eq ptr %0, null
  br i1 %.not6.not, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %2, %5
  %.07 = phi ptr [ %7, %5 ], [ %0, %2 ]
  %3 = load i32, ptr %.07, align 8, !tbaa !5
  %4 = icmp eq i32 %3, %1
  br i1 %4, label %._crit_edge, label %5

5:                                                ; preds = %.lr.ph
  %6 = getelementptr inbounds i8, ptr %.07, i64 8
  %7 = load ptr, ptr %6, align 8, !tbaa !11
  %.not.not = icmp eq ptr %7, null
  br i1 %.not.not, label %._crit_edge, label %.lr.ph, !llvm.loop !12

._crit_edge:                                      ; preds = %.lr.ph, %5, %2
  %.not.lcssa = phi i1 [ false, %2 ], [ %4, %5 ], [ %4, %.lr.ph ]
  ret i1 %.not.lcssa
}

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, !7, i64 0}
!6 = !{!"ListNode", !7, i64 0, !10, i64 8}
!7 = !{!"int", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C/C++ TBAA"}
!10 = !{!"any pointer", !8, i64 0}
!11 = !{!6, !10, i64 8}
!12 = distinct !{!12, !13}
!13 = !{!"llvm.loop.mustprogress"}


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