; LLVM IR from JessonYue/LeetCodeLearning :: Array/huyang/07之前 (指针反转字符串)

; 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"

@__const.main.a = external hidden unnamed_addr constant [13 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [3 x i8], align 1

; Function Attrs: nounwind uwtable
declare dso_local void @swap(ptr noundef, ptr noundef) #0

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

declare i32 @printf(ptr noundef, ...) #2

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

; Function Attrs: nounwind uwtable
define dso_local i32 @main() #0 {
  %1 = alloca i32, align 4
  %2 = alloca [13 x i8], align 1
  %3 = alloca ptr, align 8
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  store i32 0, ptr %1, align 4
  call void @llvm.lifetime.start.p0(i64 13, ptr %2) #4
  call void @llvm.memcpy.p0.p0.i64(ptr align 1 %2, ptr align 1 @__const.main.a, i64 13, i1 false)
  call void @llvm.lifetime.start.p0(i64 8, ptr %3) #4
  %6 = getelementptr inbounds [13 x i8], ptr %2, i64 0, i64 0
  store ptr %6, ptr %3, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #4
  %7 = getelementptr inbounds [13 x i8], ptr %2, i64 0, i64 0
  store ptr %7, ptr %4, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #4
  store i32 13, ptr %5, align 4, !tbaa !9
  br label %8

8:                                                ; preds = %13, %0
  %9 = load ptr, ptr %4, align 8, !tbaa !5
  %10 = load i8, ptr %9, align 1, !tbaa !11
  %11 = sext i8 %10 to i32
  %12 = icmp ne i32 %11, 0
  br i1 %12, label %13, label %16

13:                                               ; preds = %8
  %14 = load ptr, ptr %4, align 8, !tbaa !5
  %15 = getelementptr inbounds i8, ptr %14, i32 1
  store ptr %15, ptr %4, align 8, !tbaa !5
  br label %8, !llvm.loop !12

16:                                               ; preds = %8
  %17 = load ptr, ptr %4, align 8, !tbaa !5
  %18 = getelementptr inbounds i8, ptr %17, i32 -1
  store ptr %18, ptr %4, align 8, !tbaa !5
  %19 = load ptr, ptr %3, align 8, !tbaa !5
  %20 = load ptr, ptr %4, align 8, !tbaa !5
  call void @swap(ptr noundef %19, ptr noundef %20)
  %21 = load ptr, ptr %3, align 8, !tbaa !5
  %22 = call i32 (ptr, ...) @printf(ptr noundef @.str.1, ptr noundef %21)
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #4
  call void @llvm.lifetime.end.p0(i64 8, ptr %3) #4
  call void @llvm.lifetime.end.p0(i64 13, ptr %2) #4
  %23 = load i32, ptr %1, align 4
  ret i32 %23
}

; Function Attrs: nocallback nofree nounwind willreturn memory(argmem: readwrite)
declare void @llvm.memcpy.p0.p0.i64(ptr noalias nocapture writeonly, ptr noalias nocapture readonly, i64, i1 immarg) #3

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 = { "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 = { nocallback nofree nounwind willreturn memory(argmem: readwrite) }
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"

@__const.main.a = external hidden unnamed_addr constant [13 x i8], align 1
@.str.1 = external hidden unnamed_addr constant [3 x i8], align 1

; Function Attrs: nounwind uwtable
declare dso_local void @swap(ptr noundef, ptr noundef) local_unnamed_addr #0

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

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

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

; Function Attrs: nounwind uwtable
define dso_local noundef i32 @main() local_unnamed_addr #0 {
  %1 = alloca [13 x i8], align 1
  call void @llvm.lifetime.start.p0(i64 13, ptr nonnull %1) #4
  call void @llvm.memcpy.p0.p0.i64(ptr noundef nonnull align 1 dereferenceable(13) %1, ptr noundef nonnull align 1 dereferenceable(13) @__const.main.a, i64 13, i1 false)
  br label %2

2:                                                ; preds = %2, %0
  %.0 = phi ptr [ %1, %0 ], [ %4, %2 ]
  %3 = load i8, ptr %.0, align 1, !tbaa !5
  %.not = icmp eq i8 %3, 0
  %4 = getelementptr inbounds i8, ptr %.0, i64 1
  br i1 %.not, label %5, label %2, !llvm.loop !8

5:                                                ; preds = %2
  %6 = getelementptr inbounds i8, ptr %.0, i64 -1
  call void @swap(ptr noundef nonnull %1, ptr noundef nonnull %6)
  %7 = call i32 (ptr, ...) @printf(ptr noundef nonnull dereferenceable(1) @.str.1, ptr noundef nonnull %1)
  call void @llvm.lifetime.end.p0(i64 13, ptr nonnull %1) #4
  ret i32 0
}

; Function Attrs: mustprogress nocallback nofree nounwind willreturn memory(argmem: readwrite)
declare void @llvm.memcpy.p0.p0.i64(ptr noalias nocapture writeonly, ptr noalias nocapture readonly, i64, i1 immarg) #3

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 = { mustprogress nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
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" }
attributes #3 = { mustprogress nocallback nofree nounwind willreturn memory(argmem: readwrite) }
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 = !{!"omnipotent char", !7, i64 0}
!7 = !{!"Simple C/C++ TBAA"}
!8 = distinct !{!8, !9}
!9 = !{!"llvm.loop.mustprogress"}


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