; LLVM IR from AllenDowney/ExercisesInC :: exercises/ex02.5 (bigint)

; 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"

@.str.3 = external hidden unnamed_addr constant [3 x i8], align 1

; 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 void @print_bigint(ptr noundef %0) #1 {
  %2 = alloca ptr, align 8
  %3 = alloca i8, align 1
  %4 = alloca i32, align 4
  store ptr %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 1, ptr %3) #3
  %5 = load ptr, ptr %2, align 8, !tbaa !5
  %6 = load i8, ptr %5, align 1, !tbaa !9
  store i8 %6, ptr %3, align 1, !tbaa !9
  %7 = load i8, ptr %3, align 1, !tbaa !9
  %8 = sext i8 %7 to i32
  %9 = icmp eq i32 %8, 0
  br i1 %9, label %10, label %11

10:                                               ; preds = %1
  store i32 1, ptr %4, align 4
  br label %17

11:                                               ; preds = %1
  %12 = load ptr, ptr %2, align 8, !tbaa !5
  %13 = getelementptr inbounds i8, ptr %12, i64 1
  call void @print_bigint(ptr noundef %13)
  %14 = load i8, ptr %3, align 1, !tbaa !9
  %15 = sext i8 %14 to i32
  %16 = call i32 (ptr, ...) @printf(ptr noundef @.str.3, i32 noundef %15)
  store i32 0, ptr %4, align 4
  br label %17

17:                                               ; preds = %11, %10
  call void @llvm.lifetime.end.p0(i64 1, ptr %3) #3
  %18 = load i32, ptr %4, align 4
  switch i32 %18, label %20 [
    i32 0, label %19
    i32 1, label %19
  ]

19:                                               ; preds = %17, %17
  ret void

20:                                               ; preds = %17
  unreachable
}

declare i32 @printf(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 = { "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 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = !{!7, !7, i64 0}


; 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"

@.str.3 = external hidden unnamed_addr constant [3 x i8], align 1

; Function Attrs: nofree nounwind uwtable
define dso_local void @print_bigint(ptr nocapture noundef readonly %0) local_unnamed_addr #0 {
  %2 = load i8, ptr %0, align 1, !tbaa !5
  %3 = icmp eq i8 %2, 0
  br i1 %3, label %common.ret3, label %4

common.ret3:                                      ; preds = %1, %4
  ret void

4:                                                ; preds = %1
  %5 = sext i8 %2 to i32
  %6 = getelementptr inbounds i8, ptr %0, i64 1
  tail call void @print_bigint(ptr noundef nonnull %6)
  %7 = tail call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.3, i32 noundef %5)
  br label %common.ret3
}

; Function Attrs: nofree nounwind
declare noundef i32 @printf(ptr nocapture noundef readonly, ...) local_unnamed_addr #1

attributes #0 = { nofree 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 = { 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 = !{!"omnipotent char", !7, i64 0}
!7 = !{!"Simple C/C++ TBAA"}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass