; LLVM IR from Dev-XYS/Algorithms :: Singly-Linked-List(Pointer).ll (Z4findi)

; 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.node = type { i32, i32, ptr }

@head = external dso_local global ptr, align 8

; 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: mustprogress nounwind uwtable
define dso_local noundef i32 @_Z4findi(i32 noundef %0) #1 {
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #2
  %6 = load ptr, ptr @head, align 8, !tbaa !9
  store ptr %6, ptr %4, align 8, !tbaa !9
  br label %7

7:                                                ; preds = %20, %1
  %8 = load ptr, ptr %4, align 8, !tbaa !9
  %9 = icmp ne ptr %8, null
  br i1 %9, label %10, label %24

10:                                               ; preds = %7
  %11 = load ptr, ptr %4, align 8, !tbaa !9
  %12 = getelementptr inbounds %struct.node, ptr %11, i32 0, i32 0
  %13 = load i32, ptr %12, align 8, !tbaa !11
  %14 = load i32, ptr %3, align 4, !tbaa !5
  %15 = icmp eq i32 %13, %14
  br i1 %15, label %16, label %20

16:                                               ; preds = %10
  %17 = load ptr, ptr %4, align 8, !tbaa !9
  %18 = getelementptr inbounds %struct.node, ptr %17, i32 0, i32 1
  %19 = load i32, ptr %18, align 4, !tbaa !13
  store i32 %19, ptr %2, align 4
  store i32 1, ptr %5, align 4
  br label %25

20:                                               ; preds = %10
  %21 = load ptr, ptr %4, align 8, !tbaa !9
  %22 = getelementptr inbounds %struct.node, ptr %21, i32 0, i32 2
  %23 = load ptr, ptr %22, align 8, !tbaa !14
  store ptr %23, ptr %4, align 8, !tbaa !9
  br label %7, !llvm.loop !15

24:                                               ; preds = %7
  store i32 -1, ptr %2, align 4
  store i32 1, ptr %5, align 4
  br label %25

25:                                               ; preds = %24, %16
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #2
  %26 = load i32, ptr %2, align 4
  ret i32 %26
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { mustprogress 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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"any pointer", !7, i64 0}
!11 = !{!12, !6, i64 0}
!12 = !{!"_ZTS4node", !6, i64 0, !6, i64 4, !10, i64 8}
!13 = !{!12, !6, i64 4}
!14 = !{!12, !10, i64 8}
!15 = distinct !{!15, !16}
!16 = !{!"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"

@head = external dso_local local_unnamed_addr global ptr, align 8

; Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(read, inaccessiblemem: none) uwtable
define dso_local noundef i32 @_Z4findi(i32 noundef %0) local_unnamed_addr #0 {
  %.07 = load ptr, ptr @head, align 8, !tbaa !5
  %.not8 = icmp eq ptr %.07, null
  br i1 %.not8, label %.loopexit, label %.lr.ph

.lr.ph:                                           ; preds = %1, %7
  %.09 = phi ptr [ %.0, %7 ], [ %.07, %1 ]
  %2 = load i32, ptr %.09, align 8, !tbaa !9
  %3 = icmp eq i32 %2, %0
  br i1 %3, label %4, label %7

4:                                                ; preds = %.lr.ph
  %5 = getelementptr inbounds i8, ptr %.09, i64 4
  %6 = load i32, ptr %5, align 4, !tbaa !12
  br label %.loopexit

7:                                                ; preds = %.lr.ph
  %8 = getelementptr inbounds i8, ptr %.09, i64 8
  %.0 = load ptr, ptr %8, align 8, !tbaa !5
  %.not = icmp eq ptr %.0, null
  br i1 %.not, label %.loopexit, label %.lr.ph, !llvm.loop !13

.loopexit:                                        ; preds = %7, %1, %4
  %.05 = phi i32 [ %6, %4 ], [ -1, %1 ], [ -1, %7 ]
  ret i32 %.05
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn 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 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!10, !11, i64 0}
!10 = !{!"_ZTS4node", !11, i64 0, !11, i64 4, !6, i64 8}
!11 = !{!"int", !7, i64 0}
!12 = !{!10, !11, i64 4}
!13 = distinct !{!13, !14}
!14 = !{!"llvm.loop.mustprogress"}


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