; LLVM IR from SSBMTonberry/pocketlzma :: ref_spec/lzma1900/CPP/Common/MyString.ll (Z26IsString1PrefixedByString2PKcS0_)

; 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: 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: mustprogress nounwind uwtable
define dso_local noundef zeroext i1 @_Z26IsString1PrefixedByString2PKcS0_(ptr noundef %0, ptr noundef %1) #1 {
  %3 = alloca i1, align 1
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca i8, align 1
  %7 = alloca i32, align 4
  %8 = alloca i8, align 1
  store ptr %0, ptr %4, align 8, !tbaa !5
  store ptr %1, ptr %5, align 8, !tbaa !5
  br label %9

9:                                                ; preds = %31, %2
  call void @llvm.lifetime.start.p0(i64 1, ptr %6) #2
  %10 = load ptr, ptr %5, align 8, !tbaa !5
  %11 = getelementptr inbounds i8, ptr %10, i32 1
  store ptr %11, ptr %5, align 8, !tbaa !5
  %12 = load i8, ptr %10, align 1, !tbaa !9
  store i8 %12, ptr %6, align 1, !tbaa !9
  %13 = load i8, ptr %6, align 1, !tbaa !9
  %14 = zext i8 %13 to i32
  %15 = icmp eq i32 %14, 0
  br i1 %15, label %16, label %17

16:                                               ; preds = %9
  store i1 true, ptr %3, align 1
  store i32 1, ptr %7, align 4
  br label %29

17:                                               ; preds = %9
  call void @llvm.lifetime.start.p0(i64 1, ptr %8) #2
  %18 = load ptr, ptr %4, align 8, !tbaa !5
  %19 = getelementptr inbounds i8, ptr %18, i32 1
  store ptr %19, ptr %4, align 8, !tbaa !5
  %20 = load i8, ptr %18, align 1, !tbaa !9
  store i8 %20, ptr %8, align 1, !tbaa !9
  %21 = load i8, ptr %8, align 1, !tbaa !9
  %22 = zext i8 %21 to i32
  %23 = load i8, ptr %6, align 1, !tbaa !9
  %24 = zext i8 %23 to i32
  %25 = icmp ne i32 %22, %24
  br i1 %25, label %26, label %27

26:                                               ; preds = %17
  store i1 false, ptr %3, align 1
  store i32 1, ptr %7, align 4
  br label %28

27:                                               ; preds = %17
  store i32 0, ptr %7, align 4
  br label %28

28:                                               ; preds = %27, %26
  call void @llvm.lifetime.end.p0(i64 1, ptr %8) #2
  br label %29

29:                                               ; preds = %28, %16
  call void @llvm.lifetime.end.p0(i64 1, ptr %6) #2
  %30 = load i32, ptr %7, align 4
  switch i32 %30, label %34 [
    i32 0, label %31
    i32 1, label %32
  ]

31:                                               ; preds = %29
  br label %9, !llvm.loop !10

32:                                               ; preds = %29
  %33 = load i1, ptr %3, align 1
  ret i1 %33

34:                                               ; preds = %29
  unreachable
}

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { 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 #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 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C++ TBAA"}
!9 = !{!7, !7, i64 0}
!10 = distinct !{!10, !11}
!11 = !{!"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(read, inaccessiblemem: none) uwtable
define dso_local noundef zeroext i1 @_Z26IsString1PrefixedByString2PKcS0_(ptr nocapture noundef readonly %0, ptr nocapture noundef readonly %1) local_unnamed_addr #0 {
  br label %3

3:                                                ; preds = %6, %2
  %.010 = phi ptr [ %1, %2 ], [ %7, %6 ]
  %.08 = phi ptr [ %0, %2 ], [ %8, %6 ]
  %4 = load i8, ptr %.010, align 1, !tbaa !5
  %5 = icmp eq i8 %4, 0
  br i1 %5, label %10, label %6

6:                                                ; preds = %3
  %7 = getelementptr inbounds i8, ptr %.010, i64 1
  %8 = getelementptr inbounds i8, ptr %.08, i64 1
  %9 = load i8, ptr %.08, align 1, !tbaa !5
  %.not = icmp eq i8 %9, %4
  br i1 %.not, label %3, label %10

10:                                               ; preds = %6, %3
  ret i1 %5
}

attributes #0 = { mustprogress nofree norecurse nosync nounwind willreturn memory(read, inaccessiblemem: 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 = !{!6, !6, i64 0}
!6 = !{!"omnipotent char", !7, i64 0}
!7 = !{!"Simple C++ TBAA"}


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