; LLVM IR from div-bargali/Data-Structures-and-Algorithms :: C/Algorithms/Searching-Algorithms (linear_search)

; 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: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture) #0

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

9:                                                ; preds = %30, %3
  %10 = load i32, ptr %8, align 4, !tbaa !5
  %11 = load i32, ptr %6, align 4, !tbaa !5
  %12 = icmp slt i32 %10, %11
  br i1 %12, label %13, label %16

13:                                               ; preds = %9
  %14 = load i32, ptr %7, align 4, !tbaa !5
  %15 = icmp eq i32 %14, -1
  br label %16

16:                                               ; preds = %13, %9
  %17 = phi i1 [ false, %9 ], [ %15, %13 ]
  br i1 %17, label %19, label %18

18:                                               ; preds = %16
  call void @llvm.lifetime.end.p0(i64 4, ptr %8) #3
  br label %33

19:                                               ; preds = %16
  %20 = load i32, ptr %4, align 4, !tbaa !5
  %21 = load ptr, ptr %5, align 8, !tbaa !9
  %22 = load i32, ptr %8, align 4, !tbaa !5
  %23 = sext i32 %22 to i64
  %24 = getelementptr inbounds i32, ptr %21, i64 %23
  %25 = load i32, ptr %24, align 4, !tbaa !5
  %26 = icmp eq i32 %20, %25
  br i1 %26, label %27, label %29

27:                                               ; preds = %19
  %28 = load i32, ptr %8, align 4, !tbaa !5
  store i32 %28, ptr %7, align 4, !tbaa !5
  br label %29

29:                                               ; preds = %27, %19
  br label %30

30:                                               ; preds = %29
  %31 = load i32, ptr %8, align 4, !tbaa !5
  %32 = add nsw i32 %31, 1
  store i32 %32, ptr %8, align 4, !tbaa !5
  br label %9, !llvm.loop !11

33:                                               ; preds = %18
  %34 = load ptr, ptr %5, align 8, !tbaa !9
  call void @free(ptr noundef %34) #3
  %35 = load i32, ptr %7, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #3
  ret i32 %35
}

; Function Attrs: nocallback nofree nosync nounwind willreturn memory(argmem: readwrite)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture) #0

; Function Attrs: nounwind
declare void @free(ptr noundef) #2

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 "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 #3 = { 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/C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"any pointer", !7, i64 0}
!11 = distinct !{!11, !12}
!12 = !{!"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: nounwind memory(argmem: readwrite, inaccessiblemem: readwrite) uwtable
define dso_local i32 @linear_search(i32 noundef %0, ptr nocapture noundef %1, i32 noundef %2) local_unnamed_addr #0 {
  %4 = icmp sgt i32 %2, 0
  br i1 %4, label %.lr.ph.preheader, label %._crit_edge

.lr.ph.preheader:                                 ; preds = %3
  %5 = zext nneg i32 %2 to i64
  br label %.lr.ph

._crit_edge.loopexit:                             ; preds = %.lr.ph
  %6 = trunc nuw nsw i64 %indvars.iv to i32
  %spec.select = select i1 %9, i32 -1, i32 %6
  br label %._crit_edge

._crit_edge:                                      ; preds = %._crit_edge.loopexit, %3
  %.09.lcssa = phi i32 [ -1, %3 ], [ %spec.select, %._crit_edge.loopexit ]
  tail call void @free(ptr noundef %1) #2
  ret i32 %.09.lcssa

.lr.ph:                                           ; preds = %.lr.ph.preheader, %.lr.ph
  %indvars.iv = phi i64 [ 0, %.lr.ph.preheader ], [ %indvars.iv.next, %.lr.ph ]
  %7 = getelementptr inbounds i32, ptr %1, i64 %indvars.iv
  %8 = load i32, ptr %7, align 4, !tbaa !5
  %9 = icmp ne i32 %8, %0
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %10 = icmp ult i64 %indvars.iv.next, %5
  %11 = and i1 %9, %10
  br i1 %11, label %.lr.ph, label %._crit_edge.loopexit, !llvm.loop !9
}

; Function Attrs: mustprogress nounwind willreturn allockind("free") memory(argmem: readwrite, inaccessiblemem: readwrite)
declare void @free(ptr allocptr nocapture noundef) local_unnamed_addr #1

attributes #0 = { nounwind memory(argmem: readwrite, inaccessiblemem: readwrite) 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 = { mustprogress nounwind willreturn allockind("free") memory(argmem: readwrite, inaccessiblemem: readwrite) "alloc-family"="malloc" "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/C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: GVNPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,LCSSAPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass