; LLVM IR from BigdogManLuo/DSPLibrary :: DSPTools/ButterWorth_Filter (filter)

; 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"

%struct.ButterQueue = type { [3 x float], i32, float, float }

; 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 @InitButterQueue(ptr noundef %0) #1 {
  %2 = alloca ptr, align 8
  %3 = alloca i32, align 4
  store ptr %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %3) #2
  store i32 0, ptr %3, align 4, !tbaa !9
  %4 = load ptr, ptr %2, align 8, !tbaa !5
  %5 = getelementptr inbounds %struct.ButterQueue, ptr %4, i32 0, i32 1
  store i32 -1, ptr %5, align 4, !tbaa !11
  store i32 0, ptr %3, align 4, !tbaa !9
  br label %6

6:                                                ; preds = %15, %1
  %7 = load i32, ptr %3, align 4, !tbaa !9
  %8 = icmp sle i32 %7, 2
  br i1 %8, label %9, label %18

9:                                                ; preds = %6
  %10 = load ptr, ptr %2, align 8, !tbaa !5
  %11 = getelementptr inbounds %struct.ButterQueue, ptr %10, i32 0, i32 0
  %12 = load i32, ptr %3, align 4, !tbaa !9
  %13 = sext i32 %12 to i64
  %14 = getelementptr inbounds [3 x float], ptr %11, i64 0, i64 %13
  store float 0.000000e+00, ptr %14, align 4, !tbaa !14
  br label %15

15:                                               ; preds = %9
  %16 = load i32, ptr %3, align 4, !tbaa !9
  %17 = add nsw i32 %16, 1
  store i32 %17, ptr %3, align 4, !tbaa !9
  br label %6, !llvm.loop !15

18:                                               ; preds = %6
  %19 = load ptr, ptr %2, align 8, !tbaa !5
  %20 = getelementptr inbounds %struct.ButterQueue, ptr %19, i32 0, i32 2
  store float 0.000000e+00, ptr %20, align 4, !tbaa !17
  %21 = load ptr, ptr %2, align 8, !tbaa !5
  %22 = getelementptr inbounds %struct.ButterQueue, ptr %21, i32 0, i32 3
  store float 0.000000e+00, ptr %22, align 4, !tbaa !18
  call void @llvm.lifetime.end.p0(i64 4, ptr %3) #2
  ret void
}

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 = { 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 = !{!12, !10, i64 12}
!12 = !{!"", !7, i64 0, !10, i64 12, !13, i64 16, !13, i64 20}
!13 = !{!"float", !7, i64 0}
!14 = !{!13, !13, i64 0}
!15 = distinct !{!15, !16}
!16 = !{!"llvm.loop.mustprogress"}
!17 = !{!12, !13, i64 16}
!18 = !{!12, !13, i64 20}


; 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 nofree norecurse nosync nounwind willreturn memory(argmem: write) uwtable
define dso_local void @InitButterQueue(ptr nocapture noundef writeonly %0) local_unnamed_addr #0 {
  %2 = getelementptr inbounds i8, ptr %0, i64 12
  store i32 -1, ptr %2, align 4, !tbaa !5
  tail call void @llvm.memset.p0.i64(ptr noundef nonnull align 4 dereferenceable(12) %0, i8 0, i64 12, i1 false), !tbaa !11
  %3 = getelementptr inbounds i8, ptr %0, i64 16
  store <2 x float> zeroinitializer, ptr %3, align 4, !tbaa !11
  ret void
}

; Function Attrs: nocallback nofree nounwind willreturn memory(argmem: write)
declare void @llvm.memset.p0.i64(ptr nocapture writeonly, i8, i64, i1 immarg) #1

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(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 = { nocallback nofree nounwind willreturn memory(argmem: write) }

!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, !9, i64 12}
!6 = !{!"", !7, i64 0, !9, i64 12, !10, i64 16, !10, i64 20}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = !{!"int", !7, i64 0}
!10 = !{!"float", !7, i64 0}
!11 = !{!10, !10, i64 0}


; Effective O3 passes: EarlyCSEPass,GVNPass,GlobalOptPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,LoopIdiomRecognizePass,LoopRotatePass,PostOrderFunctionAttrsPass,SLPVectorizerPass,SROAPass,SimplifyCFGPass,TailCallElimPass