; LLVM IR from bartobri/data-structures-c :: symbol-table/array-key-index (st)

; 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"

@st = external hidden global ptr, align 8
@M = external hidden global i32, align 4

; Function Attrs: nounwind uwtable
define dso_local void @STinit(i32 noundef %0) #0 {
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  store i32 %0, ptr %2, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #3
  %4 = load i32, ptr %2, align 4, !tbaa !5
  %5 = add nsw i32 %4, 1
  %6 = sext i32 %5 to i64
  %7 = mul i64 %6, 8
  %8 = call noalias ptr @malloc(i64 noundef %7) #4
  store ptr %8, ptr @st, align 8, !tbaa !9
  store i32 0, ptr %3, align 4, !tbaa !5
  br label %9

9:                                                ; preds = %18, %1
  %10 = load i32, ptr %3, align 4, !tbaa !5
  %11 = load i32, ptr %2, align 4, !tbaa !5
  %12 = icmp sle i32 %10, %11
  br i1 %12, label %13, label %21

13:                                               ; preds = %9
  %14 = load ptr, ptr @st, align 8, !tbaa !9
  %15 = load i32, ptr %3, align 4, !tbaa !5
  %16 = sext i32 %15 to i64
  %17 = getelementptr inbounds ptr, ptr %14, i64 %16
  store ptr null, ptr %17, align 8, !tbaa !9
  br label %18

18:                                               ; preds = %13
  %19 = load i32, ptr %3, align 4, !tbaa !5
  %20 = add nsw i32 %19, 1
  store i32 %20, ptr %3, align 4, !tbaa !5
  br label %9, !llvm.loop !11

21:                                               ; preds = %9
  %22 = load i32, ptr %2, align 4, !tbaa !5
  store i32 %22, ptr @M, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #3
  ret void
}

; 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"

@st = external hidden local_unnamed_addr global ptr, align 8
@M = external hidden local_unnamed_addr global i32, align 4

; Function Attrs: nofree nounwind memory(readwrite, argmem: write) uwtable
define dso_local void @STinit(i32 noundef %0) local_unnamed_addr #0 {
  %2 = add i32 %0, 1
  %3 = sext i32 %2 to i64
  %4 = shl nsw i64 %3, 3
  %5 = tail call noalias ptr @malloc(i64 noundef %4) #2
  store ptr %5, ptr @st, align 8, !tbaa !5
  %.not7 = icmp slt i32 %0, 0
  br i1 %.not7, label %._crit_edge, label %.lr.ph.preheader

.lr.ph.preheader:                                 ; preds = %1
  %wide.trip.count = zext i32 %2 to i64
  %xtraiter = and i64 %wide.trip.count, 3
  %6 = icmp ult i32 %2, 4
  br i1 %6, label %._crit_edge.loopexit.unr-lcssa, label %.lr.ph.preheader.new

.lr.ph.preheader.new:                             ; preds = %.lr.ph.preheader
  %unroll_iter = and i64 %wide.trip.count, 4294967292
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph, %.lr.ph.preheader.new
  %indvars.iv = phi i64 [ 0, %.lr.ph.preheader.new ], [ %indvars.iv.next.3, %.lr.ph ]
  %niter = phi i64 [ 0, %.lr.ph.preheader.new ], [ %niter.next.3, %.lr.ph ]
  %7 = load ptr, ptr @st, align 8, !tbaa !5
  %8 = getelementptr inbounds ptr, ptr %7, i64 %indvars.iv
  store ptr null, ptr %8, align 8, !tbaa !5
  %indvars.iv.next = or disjoint i64 %indvars.iv, 1
  %9 = load ptr, ptr @st, align 8, !tbaa !5
  %10 = getelementptr inbounds ptr, ptr %9, i64 %indvars.iv.next
  store ptr null, ptr %10, align 8, !tbaa !5
  %indvars.iv.next.1 = or disjoint i64 %indvars.iv, 2
  %11 = load ptr, ptr @st, align 8, !tbaa !5
  %12 = getelementptr inbounds ptr, ptr %11, i64 %indvars.iv.next.1
  store ptr null, ptr %12, align 8, !tbaa !5
  %indvars.iv.next.2 = or disjoint i64 %indvars.iv, 3
  %13 = load ptr, ptr @st, align 8, !tbaa !5
  %14 = getelementptr inbounds ptr, ptr %13, i64 %indvars.iv.next.2
  store ptr null, ptr %14, align 8, !tbaa !5
  %indvars.iv.next.3 = add nuw nsw i64 %indvars.iv, 4
  %niter.next.3 = add i64 %niter, 4
  %niter.ncmp.3 = icmp eq i64 %niter.next.3, %unroll_iter
  br i1 %niter.ncmp.3, label %._crit_edge.loopexit.unr-lcssa, label %.lr.ph, !llvm.loop !9

._crit_edge.loopexit.unr-lcssa:                   ; preds = %.lr.ph, %.lr.ph.preheader
  %indvars.iv.unr = phi i64 [ 0, %.lr.ph.preheader ], [ %indvars.iv.next.3, %.lr.ph ]
  %lcmp.mod.not = icmp eq i64 %xtraiter, 0
  br i1 %lcmp.mod.not, label %._crit_edge, label %.lr.ph.epil

.lr.ph.epil:                                      ; preds = %._crit_edge.loopexit.unr-lcssa, %.lr.ph.epil
  %indvars.iv.epil = phi i64 [ %indvars.iv.next.epil, %.lr.ph.epil ], [ %indvars.iv.unr, %._crit_edge.loopexit.unr-lcssa ]
  %epil.iter = phi i64 [ %epil.iter.next, %.lr.ph.epil ], [ 0, %._crit_edge.loopexit.unr-lcssa ]
  %15 = load ptr, ptr @st, align 8, !tbaa !5
  %16 = getelementptr inbounds ptr, ptr %15, i64 %indvars.iv.epil
  store ptr null, ptr %16, align 8, !tbaa !5
  %indvars.iv.next.epil = add nuw nsw i64 %indvars.iv.epil, 1
  %epil.iter.next = add i64 %epil.iter, 1
  %epil.iter.cmp.not = icmp eq i64 %epil.iter.next, %xtraiter
  br i1 %epil.iter.cmp.not, label %._crit_edge, label %.lr.ph.epil, !llvm.loop !11

._crit_edge:                                      ; preds = %._crit_edge.loopexit.unr-lcssa, %.lr.ph.epil, %1
  store i32 %0, ptr @M, align 4, !tbaa !13
  ret void
}

; 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(readwrite, argmem: write) 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"}
!11 = distinct !{!11, !12}
!12 = !{!"llvm.loop.unroll.disable"}
!13 = !{!14, !14, i64 0}
!14 = !{!"int", !7, i64 0}


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