; LLVM IR from BrunoLevy/learn-fpga :: FemtoRV/FIRMWARE/EXAMPLES (pi)

; 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: nounwind uwtable
define dso_local i32 @inv_mod(i32 noundef %0, i32 noundef %1) #0 {
  %3 = alloca i32, align 4
  %4 = alloca i32, align 4
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  %8 = alloca i32, align 4
  %9 = alloca i32, align 4
  %10 = alloca i32, align 4
  store i32 %0, ptr %3, align 4, !tbaa !5
  store i32 %1, ptr %4, align 4, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #2
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #2
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #2
  call void @llvm.lifetime.start.p0(i64 4, ptr %8) #2
  call void @llvm.lifetime.start.p0(i64 4, ptr %9) #2
  call void @llvm.lifetime.start.p0(i64 4, ptr %10) #2
  %11 = load i32, ptr %3, align 4, !tbaa !5
  store i32 %11, ptr %6, align 4, !tbaa !5
  %12 = load i32, ptr %4, align 4, !tbaa !5
  store i32 %12, ptr %7, align 4, !tbaa !5
  store i32 1, ptr %9, align 4, !tbaa !5
  store i32 0, ptr %8, align 4, !tbaa !5
  br label %13

13:                                               ; preds = %31, %2
  %14 = load i32, ptr %7, align 4, !tbaa !5
  %15 = load i32, ptr %6, align 4, !tbaa !5
  %16 = sdiv i32 %14, %15
  store i32 %16, ptr %5, align 4, !tbaa !5
  %17 = load i32, ptr %9, align 4, !tbaa !5
  store i32 %17, ptr %10, align 4, !tbaa !5
  %18 = load i32, ptr %8, align 4, !tbaa !5
  %19 = load i32, ptr %5, align 4, !tbaa !5
  %20 = load i32, ptr %9, align 4, !tbaa !5
  %21 = mul nsw i32 %19, %20
  %22 = sub nsw i32 %18, %21
  store i32 %22, ptr %9, align 4, !tbaa !5
  %23 = load i32, ptr %10, align 4, !tbaa !5
  store i32 %23, ptr %8, align 4, !tbaa !5
  %24 = load i32, ptr %6, align 4, !tbaa !5
  store i32 %24, ptr %10, align 4, !tbaa !5
  %25 = load i32, ptr %7, align 4, !tbaa !5
  %26 = load i32, ptr %5, align 4, !tbaa !5
  %27 = load i32, ptr %6, align 4, !tbaa !5
  %28 = mul nsw i32 %26, %27
  %29 = sub nsw i32 %25, %28
  store i32 %29, ptr %6, align 4, !tbaa !5
  %30 = load i32, ptr %10, align 4, !tbaa !5
  store i32 %30, ptr %7, align 4, !tbaa !5
  br label %31

31:                                               ; preds = %13
  %32 = load i32, ptr %6, align 4, !tbaa !5
  %33 = icmp ne i32 %32, 0
  br i1 %33, label %13, label %34, !llvm.loop !9

34:                                               ; preds = %31
  %35 = load i32, ptr %8, align 4, !tbaa !5
  %36 = load i32, ptr %4, align 4, !tbaa !5
  %37 = srem i32 %35, %36
  store i32 %37, ptr %8, align 4, !tbaa !5
  %38 = load i32, ptr %8, align 4, !tbaa !5
  %39 = icmp slt i32 %38, 0
  br i1 %39, label %40, label %44

40:                                               ; preds = %34
  %41 = load i32, ptr %4, align 4, !tbaa !5
  %42 = load i32, ptr %8, align 4, !tbaa !5
  %43 = add nsw i32 %41, %42
  store i32 %43, ptr %8, align 4, !tbaa !5
  br label %44

44:                                               ; preds = %40, %34
  %45 = load i32, ptr %8, align 4, !tbaa !5
  call void @llvm.lifetime.end.p0(i64 4, ptr %10) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %9) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %8) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #2
  ret i32 %45
}

; 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 = { 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/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: nofree norecurse nosync nounwind memory(none) uwtable
define dso_local i32 @inv_mod(i32 noundef %0, i32 noundef %1) local_unnamed_addr #0 {
  br label %3

3:                                                ; preds = %3, %2
  %.023 = phi i32 [ %1, %2 ], [ %.0, %3 ]
  %.022 = phi i32 [ 0, %2 ], [ %.021, %3 ]
  %.021 = phi i32 [ 1, %2 ], [ %6, %3 ]
  %.0 = phi i32 [ %0, %2 ], [ %.recomposed, %3 ]
  %4 = sdiv i32 %.023, %.0
  %5 = mul nsw i32 %4, %.021
  %6 = sub nsw i32 %.022, %5
  %7 = mul nsw i32 %4, %.0
  %.recomposed = srem i32 %.023, %.0
  %.not = icmp eq i32 %.recomposed, 0
  br i1 %.not, label %8, label %3, !llvm.loop !5

8:                                                ; preds = %3
  %9 = srem i32 %.021, %1
  %10 = icmp slt i32 %9, 0
  %11 = select i1 %10, i32 %1, i32 0
  %spec.select = add nsw i32 %11, %9
  ret i32 %spec.select
}

attributes #0 = { nofree norecurse nosync nounwind 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: DivRemPairsPass,GVNPass,GlobalOptPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,LCSSAPass,LoopUnrollPass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass