; LLVM IR from fhanau/Efficient-Compression-Tool :: src/zopfli (util)

; 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: nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare i32 @llvm.ctlz.i32(i32, i1 immarg) #0

; 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 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 @ZopfliGetDistSymbol(i32 noundef %0) #2 {
  %2 = alloca i32, align 4
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  %6 = load i32, ptr %3, align 4, !tbaa !5
  %7 = icmp slt i32 %6, 5
  br i1 %7, label %8, label %11

8:                                                ; preds = %1
  %9 = load i32, ptr %3, align 4, !tbaa !5
  %10 = sub nsw i32 %9, 1
  store i32 %10, ptr %2, align 4
  br label %26

11:                                               ; preds = %1
  call void @llvm.lifetime.start.p0(i64 4, ptr %4) #3
  %12 = load i32, ptr %3, align 4, !tbaa !5
  %13 = sub nsw i32 %12, 1
  %14 = call i32 @llvm.ctlz.i32(i32 %13, i1 true)
  %15 = xor i32 31, %14
  store i32 %15, ptr %4, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #3
  %16 = load i32, ptr %3, align 4, !tbaa !5
  %17 = sub nsw i32 %16, 1
  %18 = load i32, ptr %4, align 4, !tbaa !5
  %19 = sub nsw i32 %18, 1
  %20 = ashr i32 %17, %19
  %21 = and i32 %20, 1
  store i32 %21, ptr %5, align 4, !tbaa !5
  %22 = load i32, ptr %4, align 4, !tbaa !5
  %23 = mul nsw i32 %22, 2
  %24 = load i32, ptr %5, align 4, !tbaa !5
  %25 = add nsw i32 %23, %24
  store i32 %25, ptr %2, align 4
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #3
  call void @llvm.lifetime.end.p0(i64 4, ptr %4) #3
  br label %26

26:                                               ; preds = %11, %8
  %27 = load i32, ptr %2, align 4
  ret i32 %27
}

attributes #0 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }
attributes #1 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #2 = { 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 #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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}


; 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: mustprogress nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare i32 @llvm.ctlz.i32(i32, i1 immarg) #0

; Function Attrs: mustprogress nofree norecurse nosync nounwind willreturn memory(none) uwtable
define dso_local range(i32 -2147483648, 62) i32 @ZopfliGetDistSymbol(i32 noundef %0) local_unnamed_addr #1 {
  %2 = icmp slt i32 %0, 5
  %3 = add nsw i32 %0, -1
  br i1 %2, label %12, label %4

4:                                                ; preds = %1
  %5 = tail call range(i32 0, 33) i32 @llvm.ctlz.i32(i32 %3, i1 true)
  %6 = sub nuw nsw i32 30, %5
  %7 = lshr i32 %3, %6
  %8 = and i32 %7, 1
  %9 = shl nuw nsw i32 %5, 1
  %10 = or disjoint i32 %8, %9
  %11 = xor i32 %10, 62
  br label %12

12:                                               ; preds = %1, %4
  %.0 = phi i32 [ %11, %4 ], [ %3, %1 ]
  ret i32 %.0
}

attributes #0 = { mustprogress nocallback nofree nosync nounwind speculatable willreturn memory(none) }
attributes #1 = { mustprogress nofree norecurse nosync nounwind willreturn memory(none) 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" }

!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)"}


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