; LLVM IR from ksw2000/Data-Structure-in-C :: Array (01-動態宣告二維陣列)

; 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 ptr @allocate2D(i32 noundef %0, i32 noundef %1) #0 {
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca ptr, align 8
  %6 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  store i32 %1, ptr %4, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %5) #3
  %7 = load i32, ptr %3, align 4, !tbaa !5
  %8 = sext i32 %7 to i64
  %9 = mul i64 8, %8
  %10 = call noalias ptr @malloc(i64 noundef %9) #4
  store ptr %10, ptr %5, align 8, !tbaa !9
  store ptr %10, ptr %5, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #3
  store i32 0, ptr %6, align 4, !tbaa !5
  br label %11

11:                                               ; preds = %24, %2
  %12 = load i32, ptr %6, align 4, !tbaa !5
  %13 = load i32, ptr %3, align 4, !tbaa !5
  %14 = icmp slt i32 %12, %13
  br i1 %14, label %15, label %27

15:                                               ; preds = %11
  %16 = load i32, ptr %4, align 4, !tbaa !5
  %17 = sext i32 %16 to i64
  %18 = mul i64 4, %17
  %19 = call noalias ptr @malloc(i64 noundef %18) #4
  %20 = load ptr, ptr %5, align 8, !tbaa !9
  %21 = load i32, ptr %6, align 4, !tbaa !5
  %22 = sext i32 %21 to i64
  %23 = getelementptr inbounds ptr, ptr %20, i64 %22
  store ptr %19, ptr %23, align 8, !tbaa !9
  br label %24

24:                                               ; preds = %15
  %25 = load i32, ptr %6, align 4, !tbaa !5
  %26 = add nsw i32 %25, 1
  store i32 %26, ptr %6, align 4, !tbaa !5
  br label %11, !llvm.loop !11

27:                                               ; preds = %11
  %28 = load ptr, ptr %5, align 8, !tbaa !9
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #3
  call void @llvm.lifetime.end.p0(i64 8, ptr %5) #3
  ret ptr %28
}

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

; Function Attrs: nounwind allocsize(0)
declare noalias ptr @malloc(i64 noundef) #2

; 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 = { nounwind allocsize(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 = { nounwind }
attributes #4 = { nounwind allocsize(0) }

!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: nofree nounwind memory(write, argmem: none, inaccessiblemem: readwrite) uwtable
define dso_local noalias noundef ptr @allocate2D(i32 noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  %3 = sext i32 %0 to i64
  %4 = shl nsw i64 %3, 3
  %5 = tail call noalias ptr @malloc(i64 noundef %4) #2
  %6 = icmp sgt i32 %0, 0
  br i1 %6, label %.lr.ph, label %._crit_edge

.lr.ph:                                           ; preds = %2
  %7 = sext i32 %1 to i64
  %8 = shl nsw i64 %7, 2
  %wide.trip.count = zext nneg i32 %0 to i64
  br label %9

9:                                                ; preds = %.lr.ph, %9
  %indvars.iv = phi i64 [ 0, %.lr.ph ], [ %indvars.iv.next, %9 ]
  %10 = tail call noalias ptr @malloc(i64 noundef %8) #2
  %11 = getelementptr inbounds ptr, ptr %5, i64 %indvars.iv
  store ptr %10, ptr %11, align 8, !tbaa !5
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %exitcond.not = icmp eq i64 %indvars.iv.next, %wide.trip.count
  br i1 %exitcond.not, label %._crit_edge, label %9, !llvm.loop !9

._crit_edge:                                      ; preds = %9, %2
  ret ptr %5
}

; Function Attrs: mustprogress nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(inaccessiblemem: readwrite)
declare noalias noundef ptr @malloc(i64 noundef) local_unnamed_addr #1

attributes #0 = { nofree nounwind memory(write, argmem: none, 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 nofree nounwind willreturn allockind("alloc,uninitialized") allocsize(0) memory(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 allocsize(0) }

!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 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,JumpThreadingPass,LICMPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass,TailCallElimPass