; LLVM IR from mirohs/gc :: util (index_of_char)

; 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.String = type { ptr, i32, i32 }

; 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 i32 @index_of_char(ptr %0, i64 %1, i8 noundef signext %2) #1 {
  %4 = alloca i32, align 4
  %5 = alloca %struct.String, align 8
  %6 = alloca i8, align 1
  %7 = alloca i32, align 4
  %8 = alloca i32, align 4
  %9 = getelementptr inbounds { ptr, i64 }, ptr %5, i32 0, i32 0
  store ptr %0, ptr %9, align 8
  %10 = getelementptr inbounds { ptr, i64 }, ptr %5, i32 0, i32 1
  store i64 %1, ptr %10, align 8
  store i8 %2, ptr %6, align 1, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #2
  store i32 0, ptr %7, align 4, !tbaa !8
  br label %11

11:                                               ; preds = %31, %3
  %12 = load i32, ptr %7, align 4, !tbaa !8
  %13 = getelementptr inbounds %struct.String, ptr %5, i32 0, i32 1
  %14 = load i32, ptr %13, align 8, !tbaa !10
  %15 = icmp slt i32 %12, %14
  br i1 %15, label %17, label %16

16:                                               ; preds = %11
  store i32 2, ptr %8, align 4
  br label %34

17:                                               ; preds = %11
  %18 = getelementptr inbounds %struct.String, ptr %5, i32 0, i32 0
  %19 = load ptr, ptr %18, align 8, !tbaa !13
  %20 = load i32, ptr %7, align 4, !tbaa !8
  %21 = sext i32 %20 to i64
  %22 = getelementptr inbounds i8, ptr %19, i64 %21
  %23 = load i8, ptr %22, align 1, !tbaa !5
  %24 = sext i8 %23 to i32
  %25 = load i8, ptr %6, align 1, !tbaa !5
  %26 = sext i8 %25 to i32
  %27 = icmp eq i32 %24, %26
  br i1 %27, label %28, label %30

28:                                               ; preds = %17
  %29 = load i32, ptr %7, align 4, !tbaa !8
  store i32 %29, ptr %4, align 4
  store i32 1, ptr %8, align 4
  br label %34

30:                                               ; preds = %17
  br label %31

31:                                               ; preds = %30
  %32 = load i32, ptr %7, align 4, !tbaa !8
  %33 = add nsw i32 %32, 1
  store i32 %33, ptr %7, align 4, !tbaa !8
  br label %11, !llvm.loop !14

34:                                               ; preds = %28, %16
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #2
  %35 = load i32, ptr %8, align 4
  switch i32 %35, label %39 [
    i32 2, label %36
    i32 1, label %37
  ]

36:                                               ; preds = %34
  store i32 -1, ptr %4, align 4
  br label %37

37:                                               ; preds = %36, %34
  %38 = load i32, ptr %4, align 4
  ret i32 %38

39:                                               ; preds = %34
  unreachable
}

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 = !{!"omnipotent char", !7, i64 0}
!7 = !{!"Simple C/C++ TBAA"}
!8 = !{!9, !9, i64 0}
!9 = !{!"int", !6, i64 0}
!10 = !{!11, !9, i64 8}
!11 = !{!"String", !12, i64 0, !9, i64 8, !9, i64 12}
!12 = !{!"any pointer", !6, i64 0}
!13 = !{!11, !12, i64 0}
!14 = distinct !{!14, !15}
!15 = !{!"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(argmem: read) uwtable
define dso_local i32 @index_of_char(ptr nocapture readonly %0, i64 %1, i8 noundef signext %2) local_unnamed_addr #0 {
  %.sroa.2.8.extract.trunc = trunc i64 %1 to i32
  %.not9 = icmp sgt i32 %.sroa.2.8.extract.trunc, 0
  br i1 %.not9, label %.lr.ph.preheader, label %._crit_edge

.lr.ph.preheader:                                 ; preds = %3
  %wide.trip.count = and i64 %1, 2147483647
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.preheader, %7
  %indvars.iv = phi i64 [ 0, %.lr.ph.preheader ], [ %indvars.iv.next, %7 ]
  %4 = getelementptr inbounds i8, ptr %0, i64 %indvars.iv
  %5 = load i8, ptr %4, align 1, !tbaa !5
  %6 = icmp eq i8 %5, %2
  br i1 %6, label %._crit_edge.loopexit.split.loop.exit, label %7

7:                                                ; preds = %.lr.ph
  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
  %exitcond.not = icmp eq i64 %indvars.iv.next, %wide.trip.count
  br i1 %exitcond.not, label %._crit_edge, label %.lr.ph, !llvm.loop !8

._crit_edge.loopexit.split.loop.exit:             ; preds = %.lr.ph
  %8 = trunc nuw nsw i64 %indvars.iv to i32
  br label %._crit_edge

._crit_edge:                                      ; preds = %7, %._crit_edge.loopexit.split.loop.exit, %3
  %spec.select = phi i32 [ -1, %3 ], [ %8, %._crit_edge.loopexit.split.loop.exit ], [ -1, %7 ]
  ret i32 %spec.select
}

attributes #0 = { nofree norecurse nosync nounwind memory(argmem: read) 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 = !{!6, !6, i64 0}
!6 = !{!"omnipotent char", !7, i64 0}
!7 = !{!"Simple C/C++ TBAA"}
!8 = distinct !{!8, !9}
!9 = !{!"llvm.loop.mustprogress"}


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