; LLVM IR from wrnlb666/yet-another-string-library-in-c :: yasli (str_char_at)

; 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_t = type { i64, i64, [1 x i8] }

; Function Attrs: nounwind uwtable
define dso_local signext i8 @str_char_at(ptr noundef %0, i64 noundef %1, i8 noundef signext %2) #0 {
  %4 = alloca i8, align 1
  %5 = alloca ptr, align 8
  %6 = alloca i64, align 8
  %7 = alloca i8, align 1
  store ptr %0, ptr %5, align 8, !tbaa !5
  store i64 %1, ptr %6, align 8, !tbaa !9
  store i8 %2, ptr %7, align 1, !tbaa !11
  %8 = load i64, ptr %6, align 8, !tbaa !9
  %9 = load ptr, ptr %5, align 8, !tbaa !5
  %10 = getelementptr inbounds %struct.string_t, ptr %9, i32 0, i32 0
  %11 = load i64, ptr %10, align 8, !tbaa !12
  %12 = icmp uge i64 %8, %11
  br i1 %12, label %13, label %14

13:                                               ; preds = %3
  store i8 0, ptr %4, align 1
  br label %30

14:                                               ; preds = %3
  %15 = load i8, ptr %7, align 1, !tbaa !11
  %16 = sext i8 %15 to i32
  %17 = icmp ne i32 %16, 0
  br i1 %17, label %18, label %24

18:                                               ; preds = %14
  %19 = load i8, ptr %7, align 1, !tbaa !11
  %20 = load ptr, ptr %5, align 8, !tbaa !5
  %21 = getelementptr inbounds %struct.string_t, ptr %20, i32 0, i32 2
  %22 = load i64, ptr %6, align 8, !tbaa !9
  %23 = getelementptr inbounds [1 x i8], ptr %21, i64 0, i64 %22
  store i8 %19, ptr %23, align 1, !tbaa !11
  br label %24

24:                                               ; preds = %18, %14
  %25 = load ptr, ptr %5, align 8, !tbaa !5
  %26 = getelementptr inbounds %struct.string_t, ptr %25, i32 0, i32 2
  %27 = load i64, ptr %6, align 8, !tbaa !9
  %28 = getelementptr inbounds [1 x i8], ptr %26, i64 0, i64 %27
  %29 = load i8, ptr %28, align 1, !tbaa !11
  store i8 %29, ptr %4, align 1
  br label %30

30:                                               ; preds = %24, %13
  %31 = load i8, ptr %4, align 1
  ret i8 %31
}

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" }

!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 = !{!"long", !7, i64 0}
!11 = !{!7, !7, i64 0}
!12 = !{!13, !10, i64 0}
!13 = !{!"string_t", !10, i64 0, !10, i64 8, !7, i64 16}


; 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: readwrite) uwtable
define dso_local signext i8 @str_char_at(ptr nocapture noundef %0, i64 noundef %1, i8 noundef signext %2) local_unnamed_addr #0 {
  %4 = load i64, ptr %0, align 8, !tbaa !5
  %.not = icmp ugt i64 %4, %1
  br i1 %.not, label %5, label %7

5:                                                ; preds = %3
  %.not9 = icmp eq i8 %2, 0
  %.phi.trans.insert = getelementptr inbounds i8, ptr %0, i64 16
  %.phi.trans.insert10 = getelementptr inbounds [1 x i8], ptr %.phi.trans.insert, i64 0, i64 %1
  br i1 %.not9, label %._crit_edge, label %6

._crit_edge:                                      ; preds = %5
  %.pre = load i8, ptr %.phi.trans.insert10, align 1, !tbaa !10
  br label %7

6:                                                ; preds = %5
  store i8 %2, ptr %.phi.trans.insert10, align 1, !tbaa !10
  br label %7

7:                                                ; preds = %6, %._crit_edge, %3
  %.0 = phi i8 [ 0, %3 ], [ %.pre, %._crit_edge ], [ %2, %6 ]
  ret i8 %.0
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(argmem: readwrite) 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, !7, i64 0}
!6 = !{!"string_t", !7, i64 0, !7, i64 8, !8, i64 16}
!7 = !{!"long", !8, i64 0}
!8 = !{!"omnipotent char", !9, i64 0}
!9 = !{!"Simple C/C++ TBAA"}
!10 = !{!8, !8, i64 0}


; Effective O3 passes: BDCEPass,EarlyCSEPass,GVNPass,GlobalOptPass,InstCombinePass,JumpThreadingPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass