; LLVM IR from s-matyukevich/raspberry-pi-os :: exercises/lesson06/1/xdfm1/src (user)

; 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 void @loop(ptr noundef %0) #0 {
  %2 = alloca ptr, align 8
  %3 = alloca [2 x i8], align 1
  %4 = alloca i32, align 4
  store ptr %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 2, ptr %3) #4
  call void @llvm.memset.p0.i64(ptr align 1 %3, i8 0, i64 2, i1 false)
  br label %5

5:                                                ; preds = %22, %1
  br label %6

6:                                                ; preds = %5
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #4
  store i32 0, ptr %4, align 4, !tbaa !9
  br label %7

7:                                                ; preds = %19, %6
  %8 = load i32, ptr %4, align 4, !tbaa !9
  %9 = icmp slt i32 %8, 5
  br i1 %9, label %11, label %10

10:                                               ; preds = %7
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #4
  br label %22

11:                                               ; preds = %7
  %12 = load ptr, ptr %2, align 8, !tbaa !5
  %13 = load i32, ptr %4, align 4, !tbaa !9
  %14 = sext i32 %13 to i64
  %15 = getelementptr inbounds i8, ptr %12, i64 %14
  %16 = load i8, ptr %15, align 1, !tbaa !11
  %17 = getelementptr inbounds [2 x i8], ptr %3, i64 0, i64 0
  store i8 %16, ptr %17, align 1, !tbaa !11
  %18 = getelementptr inbounds [2 x i8], ptr %3, i64 0, i64 0
  call void @call_sys_write(ptr noundef %18)
  call void @user_delay(i64 noundef 1000000)
  br label %19

19:                                               ; preds = %11
  %20 = load i32, ptr %4, align 4, !tbaa !9
  %21 = add nsw i32 %20, 1
  store i32 %21, ptr %4, align 4, !tbaa !9
  br label %7, !llvm.loop !12

22:                                               ; preds = %10
  br label %5
}

; 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 nounwind willreturn memory(argmem: write)
declare void @llvm.memset.p0.i64(ptr nocapture writeonly, i8, i64, i1 immarg) #2

declare void @call_sys_write(ptr noundef) #3

declare void @user_delay(i64 noundef) #3

; 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 = { nocallback nofree nounwind willreturn memory(argmem: write) }
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 = !{!"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: noreturn nounwind uwtable
define dso_local void @loop(ptr nocapture noundef readonly %0) local_unnamed_addr #0 {
  %2 = alloca [2 x i8], align 2
  call void @llvm.lifetime.start.p0(i64 2, ptr nonnull %2) #3
  store i16 0, ptr %2, align 2
  %3 = getelementptr inbounds i8, ptr %0, i64 1
  %4 = getelementptr inbounds i8, ptr %0, i64 2
  %5 = getelementptr inbounds i8, ptr %0, i64 3
  %6 = getelementptr inbounds i8, ptr %0, i64 4
  br label %.loopexit

.loopexit:                                        ; preds = %.loopexit, %1
  %7 = load i8, ptr %0, align 1, !tbaa !5
  store i8 %7, ptr %2, align 2, !tbaa !5
  call void @call_sys_write(ptr noundef nonnull %2) #3
  call void @user_delay(i64 noundef 1000000) #3
  %8 = load i8, ptr %3, align 1, !tbaa !5
  store i8 %8, ptr %2, align 2, !tbaa !5
  call void @call_sys_write(ptr noundef nonnull %2) #3
  call void @user_delay(i64 noundef 1000000) #3
  %9 = load i8, ptr %4, align 1, !tbaa !5
  store i8 %9, ptr %2, align 2, !tbaa !5
  call void @call_sys_write(ptr noundef nonnull %2) #3
  call void @user_delay(i64 noundef 1000000) #3
  %10 = load i8, ptr %5, align 1, !tbaa !5
  store i8 %10, ptr %2, align 2, !tbaa !5
  call void @call_sys_write(ptr noundef nonnull %2) #3
  call void @user_delay(i64 noundef 1000000) #3
  %11 = load i8, ptr %6, align 1, !tbaa !5
  store i8 %11, ptr %2, align 2, !tbaa !5
  call void @call_sys_write(ptr noundef nonnull %2) #3
  call void @user_delay(i64 noundef 1000000) #3
  br label %.loopexit, !llvm.loop !8
}

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

declare void @call_sys_write(ptr noundef) local_unnamed_addr #2

declare void @user_delay(i64 noundef) local_unnamed_addr #2

attributes #0 = { noreturn 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 nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { "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 = !{!"omnipotent char", !7, i64 0}
!7 = !{!"Simple C/C++ TBAA"}
!8 = distinct !{!8, !9}
!9 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: EarlyCSEPass,GVNPass,GlobalOptPass,IndVarSimplifyPass,InferAlignmentPass,InferFunctionAttrsPass,InstCombinePass,LICMPass,LoopRotatePass,LoopSimplifyPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass