; LLVM IR from Dev-XYS/Algorithms :: Gaussian-Elimination (main)

; 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"

@n = external dso_local global i32, align 4
@a = external dso_local global [15 x [15 x double]], align 16
@s = external dso_local global [15 x double], align 16
@.str = external hidden unnamed_addr constant [3 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [4 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [15 x i8], align 1

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_Z20gaussian_eliminationv() #0

; 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

; Function Attrs: mustprogress norecurse uwtable
define dso_local noundef i32 @main() #2 {
  %1 = alloca i32, align 4
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  %6 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str, ptr noundef @n)
  call void @llvm.lifetime.start.p0(i64 4, ptr %2) #4
  store i32 0, ptr %2, align 4, !tbaa !5
  br label %7

7:                                                ; preds = %37, %0
  %8 = load i32, ptr %2, align 4, !tbaa !5
  %9 = load i32, ptr @n, align 4, !tbaa !5
  %10 = icmp slt i32 %8, %9
  br i1 %10, label %12, label %11

11:                                               ; preds = %7
  store i32 2, ptr %3, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %2) #4
  br label %40

12:                                               ; preds = %7
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #4
  store i32 0, ptr %4, align 4, !tbaa !5
  br label %13

13:                                               ; preds = %26, %12
  %14 = load i32, ptr %4, align 4, !tbaa !5
  %15 = load i32, ptr @n, align 4, !tbaa !5
  %16 = icmp slt i32 %14, %15
  br i1 %16, label %18, label %17

17:                                               ; preds = %13
  store i32 5, ptr %3, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #4
  br label %29

18:                                               ; preds = %13
  %19 = load i32, ptr %2, align 4, !tbaa !5
  %20 = sext i32 %19 to i64
  %21 = getelementptr inbounds [15 x [15 x double]], ptr @a, i64 0, i64 %20
  %22 = load i32, ptr %4, align 4, !tbaa !5
  %23 = sext i32 %22 to i64
  %24 = getelementptr inbounds [15 x double], ptr %21, i64 0, i64 %23
  %25 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str.1, ptr noundef %24)
  br label %26

26:                                               ; preds = %18
  %27 = load i32, ptr %4, align 4, !tbaa !5
  %28 = add nsw i32 %27, 1
  store i32 %28, ptr %4, align 4, !tbaa !5
  br label %13, !llvm.loop !9

29:                                               ; preds = %17
  %30 = load i32, ptr %2, align 4, !tbaa !5
  %31 = sext i32 %30 to i64
  %32 = getelementptr inbounds [15 x [15 x double]], ptr @a, i64 0, i64 %31
  %33 = load i32, ptr @n, align 4, !tbaa !5
  %34 = sext i32 %33 to i64
  %35 = getelementptr inbounds [15 x double], ptr %32, i64 0, i64 %34
  %36 = call i32 (ptr, ...) @__isoc99_scanf(ptr noundef @.str.1, ptr noundef %35)
  br label %37

37:                                               ; preds = %29
  %38 = load i32, ptr %2, align 4, !tbaa !5
  %39 = add nsw i32 %38, 1
  store i32 %39, ptr %2, align 4, !tbaa !5
  br label %7, !llvm.loop !11

40:                                               ; preds = %11
  call void @_Z20gaussian_eliminationv()
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #4
  store i32 0, ptr %5, align 4, !tbaa !5
  br label %41

41:                                               ; preds = %53, %40
  %42 = load i32, ptr %5, align 4, !tbaa !5
  %43 = load i32, ptr @n, align 4, !tbaa !5
  %44 = icmp slt i32 %42, %43
  br i1 %44, label %46, label %45

45:                                               ; preds = %41
  store i32 8, ptr %3, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #4
  br label %56

46:                                               ; preds = %41
  %47 = load i32, ptr %5, align 4, !tbaa !5
  %48 = load i32, ptr %5, align 4, !tbaa !5
  %49 = sext i32 %48 to i64
  %50 = getelementptr inbounds [15 x double], ptr @s, i64 0, i64 %49
  %51 = load double, ptr %50, align 8, !tbaa !12
  %52 = call i32 (ptr, ...) @printf(ptr noundef @.str.2, i32 noundef %47, double noundef %51)
  br label %53

53:                                               ; preds = %46
  %54 = load i32, ptr %5, align 4, !tbaa !5
  %55 = add nsw i32 %54, 1
  store i32 %55, ptr %5, align 4, !tbaa !5
  br label %41, !llvm.loop !14

56:                                               ; preds = %45
  ret i32 0
}

declare i32 @__isoc99_scanf(ptr noundef, ...) #3

declare i32 @printf(ptr noundef, ...) #3

attributes #0 = { 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 #1 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { mustprogress norecurse 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 #3 = { "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 #4 = { 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 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = distinct !{!11, !10}
!12 = !{!13, !13, i64 0}
!13 = !{!"double", !7, i64 0}
!14 = distinct !{!14, !10}


; 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"

@n = external dso_local global i32, align 4
@a = external dso_local global [15 x [15 x double]], align 16
@s = external dso_local local_unnamed_addr global [15 x double], align 16
@.str = external hidden unnamed_addr constant [3 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [4 x i8], align 1
@.str.2 = external hidden unnamed_addr constant [15 x i8], align 1

; Function Attrs: mustprogress nounwind uwtable
declare dso_local void @_Z20gaussian_eliminationv() local_unnamed_addr #0

; Function Attrs: mustprogress norecurse nounwind uwtable
define dso_local noundef i32 @main() local_unnamed_addr #1 {
  %1 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str, ptr noundef nonnull @n)
  %2 = load i32, ptr @n, align 4, !tbaa !5
  %3 = icmp sgt i32 %2, 0
  br i1 %3, label %.preheader, label %._crit_edge16

.preheader:                                       ; preds = %0, %._crit_edge
  %4 = phi i32 [ %10, %._crit_edge ], [ %2, %0 ]
  %indvars.iv23 = phi i64 [ %indvars.iv.next24, %._crit_edge ], [ 0, %0 ]
  %5 = icmp sgt i32 %4, 0
  br i1 %5, label %.lr.ph, label %.preheader.._crit_edge_crit_edge

.preheader.._crit_edge_crit_edge:                 ; preds = %.preheader
  %.pre = sext i32 %4 to i64
  br label %._crit_edge

._crit_edge16:                                    ; preds = %._crit_edge, %0
  tail call void @_Z20gaussian_eliminationv()
  %6 = load i32, ptr @n, align 4, !tbaa !5
  %7 = icmp sgt i32 %6, 0
  br i1 %7, label %.lr.ph19, label %._crit_edge20

._crit_edge:                                      ; preds = %.lr.ph, %.preheader.._crit_edge_crit_edge
  %.pre-phi = phi i64 [ %.pre, %.preheader.._crit_edge_crit_edge ], [ %16, %.lr.ph ]
  %8 = getelementptr inbounds [15 x [15 x double]], ptr @a, i64 0, i64 %indvars.iv23, i64 %.pre-phi
  %9 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str.1, ptr noundef nonnull %8)
  %indvars.iv.next24 = add nuw nsw i64 %indvars.iv23, 1
  %10 = load i32, ptr @n, align 4, !tbaa !5
  %11 = sext i32 %10 to i64
  %12 = icmp slt i64 %indvars.iv.next24, %11
  br i1 %12, label %.preheader, label %._crit_edge16, !llvm.loop !9

.lr.ph:                                           ; preds = %.preheader, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 0, %.preheader ]
  %13 = getelementptr inbounds [15 x [15 x double]], ptr @a, i64 0, i64 %indvars.iv23, i64 %indvars.iv
  %14 = tail call i32 (ptr, ...) @__isoc99_scanf(ptr noundef nonnull @.str.1, ptr noundef nonnull %13)
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %15 = load i32, ptr @n, align 4, !tbaa !5
  %16 = sext i32 %15 to i64
  %17 = icmp slt i64 %indvars.iv.next, %16
  br i1 %17, label %.lr.ph, label %._crit_edge, !llvm.loop !11

._crit_edge20:                                    ; preds = %.lr.ph19, %._crit_edge16
  ret i32 0

.lr.ph19:                                         ; preds = %._crit_edge16, %.lr.ph19
  %indvars.iv26 = phi i64 [ %indvars.iv.next27, %.lr.ph19 ], [ 0, %._crit_edge16 ]
  %18 = getelementptr inbounds [15 x double], ptr @s, i64 0, i64 %indvars.iv26
  %19 = load double, ptr %18, align 8, !tbaa !12
  %20 = trunc nuw nsw i64 %indvars.iv26 to i32
  %21 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.2, i32 noundef %20, double noundef %19)
  %indvars.iv.next27 = add nuw nsw i64 %indvars.iv26, 1
  %22 = load i32, ptr @n, align 4, !tbaa !5
  %23 = sext i32 %22 to i64
  %24 = icmp slt i64 %indvars.iv.next27, %23
  br i1 %24, label %.lr.ph19, label %._crit_edge20, !llvm.loop !14
}

; Function Attrs: nofree nounwind
declare noundef i32 @__isoc99_scanf(ptr nocapture noundef readonly, ...) local_unnamed_addr #2

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #2

attributes #0 = { 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 #1 = { mustprogress norecurse 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 = { nofree 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" }

!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 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}
!11 = distinct !{!11, !10}
!12 = !{!13, !13, i64 0}
!13 = !{!"double", !7, i64 0}
!14 = distinct !{!14, !10}


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