; LLVM IR from upupming/algorithm :: acwing/算法基础课/第四讲 数学知识/求组合数/887. 求组合数 III.ll (Z1Ciii)

; 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: mustprogress nounwind uwtable
declare dso_local noundef i32 @_Z4qpowiii(i32 noundef, i32 noundef, i32 noundef) #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: mustprogress nounwind uwtable
define dso_local noundef i32 @_Z1Ciii(i32 noundef %0, i32 noundef %1, i32 noundef %2) #0 {
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  %8 = alloca i64, align 8
  %9 = alloca i32, align 4
  %10 = alloca i32, align 4
  store i32 %0, ptr %5, align 4, !tbaa !5
  store i32 %1, ptr %6, align 4, !tbaa !5
  store i32 %2, ptr %7, align 4, !tbaa !5
  %11 = load i32, ptr %6, align 4, !tbaa !5
  %12 = load i32, ptr %5, align 4, !tbaa !5
  %13 = icmp sgt i32 %11, %12
  br i1 %13, label %14, label %15

14:                                               ; preds = %3
  store i32 0, ptr %4, align 4
  br label %49

15:                                               ; preds = %3
  call void @llvm.lifetime.start.p0(i64 8, ptr %8) #2
  store i64 1, ptr %8, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %9) #2
  store i32 1, ptr %9, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %10) #2
  %16 = load i32, ptr %5, align 4, !tbaa !5
  store i32 %16, ptr %10, align 4, !tbaa !5
  br label %17

17:                                               ; preds = %41, %15
  %18 = load i32, ptr %9, align 4, !tbaa !5
  %19 = load i32, ptr %6, align 4, !tbaa !5
  %20 = icmp sle i32 %18, %19
  br i1 %20, label %22, label %21

21:                                               ; preds = %17
  call void @llvm.lifetime.end.p0(i64 4, ptr %10) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %9) #2
  br label %46

22:                                               ; preds = %17
  %23 = load i64, ptr %8, align 8, !tbaa !9
  %24 = load i32, ptr %10, align 4, !tbaa !5
  %25 = sext i32 %24 to i64
  %26 = mul nsw i64 %23, %25
  %27 = load i32, ptr %7, align 4, !tbaa !5
  %28 = sext i32 %27 to i64
  %29 = srem i64 %26, %28
  store i64 %29, ptr %8, align 8, !tbaa !9
  %30 = load i64, ptr %8, align 8, !tbaa !9
  %31 = load i32, ptr %9, align 4, !tbaa !5
  %32 = load i32, ptr %7, align 4, !tbaa !5
  %33 = sub nsw i32 %32, 2
  %34 = load i32, ptr %7, align 4, !tbaa !5
  %35 = call noundef i32 @_Z4qpowiii(i32 noundef %31, i32 noundef %33, i32 noundef %34)
  %36 = sext i32 %35 to i64
  %37 = mul nsw i64 %30, %36
  %38 = load i32, ptr %7, align 4, !tbaa !5
  %39 = sext i32 %38 to i64
  %40 = srem i64 %37, %39
  store i64 %40, ptr %8, align 8, !tbaa !9
  br label %41

41:                                               ; preds = %22
  %42 = load i32, ptr %9, align 4, !tbaa !5
  %43 = add nsw i32 %42, 1
  store i32 %43, ptr %9, align 4, !tbaa !5
  %44 = load i32, ptr %10, align 4, !tbaa !5
  %45 = add nsw i32 %44, -1
  store i32 %45, ptr %10, align 4, !tbaa !5
  br label %17, !llvm.loop !11

46:                                               ; preds = %21
  %47 = load i64, ptr %8, align 8, !tbaa !9
  %48 = trunc i64 %47 to i32
  store i32 %48, ptr %4, align 4
  call void @llvm.lifetime.end.p0(i64 8, ptr %8) #2
  br label %49

49:                                               ; preds = %46, %14
  %50 = load i32, ptr %4, align 4
  ret i32 %50
}

attributes #0 = { mustprogress 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 }

!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++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"long long", !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: mustprogress nounwind uwtable
declare dso_local noundef i32 @_Z4qpowiii(i32 noundef, i32 noundef, i32 noundef) local_unnamed_addr #0

; Function Attrs: mustprogress nounwind uwtable
define dso_local noundef range(i32 -2147483647, -2147483648) i32 @_Z1Ciii(i32 noundef %0, i32 noundef %1, i32 noundef %2) local_unnamed_addr #0 {
  %4 = icmp sgt i32 %1, %0
  br i1 %4, label %._crit_edge, label %.preheader

.preheader:                                       ; preds = %3
  %.not22 = icmp slt i32 %1, 1
  br i1 %.not22, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %.preheader
  %5 = sext i32 %2 to i64
  %6 = add nsw i32 %2, -2
  %7 = sext i32 %0 to i64
  br label %9

._crit_edge.loopexit:                             ; preds = %9
  %8 = trunc nsw i64 %15 to i32
  br label %._crit_edge

9:                                                ; preds = %.lr.ph, %9
  %indvars.iv = phi i64 [ %7, %.lr.ph ], [ %indvars.iv.next, %9 ]
  %.01724 = phi i32 [ 1, %.lr.ph ], [ %16, %9 ]
  %.01823 = phi i64 [ 1, %.lr.ph ], [ %15, %9 ]
  %10 = mul nsw i64 %.01823, %indvars.iv
  %11 = srem i64 %10, %5
  %12 = tail call noundef i32 @_Z4qpowiii(i32 noundef %.01724, i32 noundef %6, i32 noundef %2)
  %13 = sext i32 %12 to i64
  %14 = mul nsw i64 %11, %13
  %15 = srem i64 %14, %5
  %16 = add nuw i32 %.01724, 1
  %indvars.iv.next = add nsw i64 %indvars.iv, -1
  %exitcond.not = icmp eq i32 %.01724, %1
  br i1 %exitcond.not, label %._crit_edge.loopexit, label %9, !llvm.loop !5

._crit_edge:                                      ; preds = %.preheader, %._crit_edge.loopexit, %3
  %.019 = phi i32 [ 0, %3 ], [ 1, %.preheader ], [ %8, %._crit_edge.loopexit ]
  ret i32 %.019
}

attributes #0 = { mustprogress 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" }

!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 = distinct !{!5, !6}
!6 = !{!"llvm.loop.mustprogress"}


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