; LLVM IR from upupming/algorithm :: acwing/算法基础课/第四讲 数学知识/快速幂/875. 快速幂.ll (Z4qpowiii)

; 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
define dso_local noundef i32 @_Z4qpowiii(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
  store i32 %0, ptr %4, align 4, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !5
  store i32 %2, ptr %6, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #2
  %8 = load i32, ptr %6, align 4, !tbaa !5
  %9 = srem i32 1, %8
  store i32 %9, ptr %7, align 4, !tbaa !5
  br label %10

10:                                               ; preds = %28, %3
  %11 = load i32, ptr %5, align 4, !tbaa !5
  %12 = icmp ne i32 %11, 0
  br i1 %12, label %13, label %41

13:                                               ; preds = %10
  %14 = load i32, ptr %5, align 4, !tbaa !5
  %15 = and i32 %14, 1
  %16 = icmp ne i32 %15, 0
  br i1 %16, label %17, label %28

17:                                               ; preds = %13
  %18 = load i32, ptr %7, align 4, !tbaa !5
  %19 = sext i32 %18 to i64
  %20 = mul nsw i64 1, %19
  %21 = load i32, ptr %4, align 4, !tbaa !5
  %22 = sext i32 %21 to i64
  %23 = mul nsw i64 %20, %22
  %24 = load i32, ptr %6, align 4, !tbaa !5
  %25 = sext i32 %24 to i64
  %26 = srem i64 %23, %25
  %27 = trunc i64 %26 to i32
  store i32 %27, ptr %7, align 4, !tbaa !5
  br label %28

28:                                               ; preds = %17, %13
  %29 = load i32, ptr %5, align 4, !tbaa !5
  %30 = ashr i32 %29, 1
  store i32 %30, ptr %5, align 4, !tbaa !5
  %31 = load i32, ptr %4, align 4, !tbaa !5
  %32 = sext i32 %31 to i64
  %33 = mul nsw i64 1, %32
  %34 = load i32, ptr %4, align 4, !tbaa !5
  %35 = sext i32 %34 to i64
  %36 = mul nsw i64 %33, %35
  %37 = load i32, ptr %6, align 4, !tbaa !5
  %38 = sext i32 %37 to i64
  %39 = srem i64 %36, %38
  %40 = trunc i64 %39 to i32
  store i32 %40, ptr %4, align 4, !tbaa !5
  br label %10, !llvm.loop !9

41:                                               ; preds = %10
  %42 = load i32, ptr %7, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #2
  ret i32 %42
}

; 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

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 = distinct !{!9, !10}
!10 = !{!"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 nofree norecurse nosync nounwind willreturn memory(none) uwtable
define dso_local noundef range(i32 -2147483647, -2147483648) i32 @_Z4qpowiii(i32 noundef %0, i32 noundef %1, i32 noundef %2) local_unnamed_addr #0 {
  %4 = srem i32 1, %2
  %.not14 = icmp eq i32 %1, 0
  br i1 %.not14, label %._crit_edge, label %.lr.ph

.lr.ph:                                           ; preds = %3
  %5 = sext i32 %2 to i64
  br label %6

6:                                                ; preds = %.lr.ph, %14
  %.017 = phi i32 [ %4, %.lr.ph ], [ %.1, %14 ]
  %.01116 = phi i32 [ %0, %.lr.ph ], [ %18, %14 ]
  %.01215 = phi i32 [ %1, %.lr.ph ], [ %15, %14 ]
  %7 = and i32 %.01215, 1
  %.not13 = icmp eq i32 %7, 0
  br i1 %.not13, label %._crit_edge18, label %8

._crit_edge18:                                    ; preds = %6
  %.pre = sext i32 %.01116 to i64
  br label %14

8:                                                ; preds = %6
  %9 = sext i32 %.017 to i64
  %10 = sext i32 %.01116 to i64
  %11 = mul nsw i64 %9, %10
  %12 = srem i64 %11, %5
  %13 = trunc nsw i64 %12 to i32
  br label %14

14:                                               ; preds = %._crit_edge18, %8
  %.pre-phi = phi i64 [ %.pre, %._crit_edge18 ], [ %10, %8 ]
  %.1 = phi i32 [ %.017, %._crit_edge18 ], [ %13, %8 ]
  %15 = ashr i32 %.01215, 1
  %16 = mul nsw i64 %.pre-phi, %.pre-phi
  %17 = srem i64 %16, %5
  %18 = trunc nsw i64 %17 to i32
  %.not = icmp ult i32 %.01215, 2
  br i1 %.not, label %._crit_edge, label %6, !llvm.loop !5

._crit_edge:                                      ; preds = %14, %3
  %.0.lcssa = phi i32 [ %4, %3 ], [ %.1, %14 ]
  ret i32 %.0.lcssa
}

attributes #0 = { 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)"}
!5 = distinct !{!5, !6}
!6 = !{!"llvm.loop.mustprogress"}


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