; LLVM IR from BrunoLevy/learn-fpga :: FemtoRV/FIRMWARE/LIBFEMTOC/missing (strcmp)

; 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 @strcmp(ptr noundef %0, ptr noundef %1) #0 {
  %3 = alloca i32, align 4
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca ptr, align 8
  %7 = alloca ptr, align 8
  %8 = alloca i8, align 1
  %9 = alloca i8, align 1
  %10 = alloca i32, align 4
  store ptr %0, ptr %4, align 8, !tbaa !5
  store ptr %1, ptr %5, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #2
  %11 = load ptr, ptr %4, align 8, !tbaa !5
  store ptr %11, ptr %6, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 8, ptr %7) #2
  %12 = load ptr, ptr %5, align 8, !tbaa !5
  store ptr %12, ptr %7, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 1, ptr %8) #2
  call void @llvm.lifetime.start.p0(i64 1, ptr %9) #2
  br label %13

13:                                               ; preds = %30, %2
  %14 = load ptr, ptr %6, align 8, !tbaa !5
  %15 = getelementptr inbounds i8, ptr %14, i32 1
  store ptr %15, ptr %6, align 8, !tbaa !5
  %16 = load i8, ptr %14, align 1, !tbaa !9
  store i8 %16, ptr %8, align 1, !tbaa !9
  %17 = load ptr, ptr %7, align 8, !tbaa !5
  %18 = getelementptr inbounds i8, ptr %17, i32 1
  store ptr %18, ptr %7, align 8, !tbaa !5
  %19 = load i8, ptr %17, align 1, !tbaa !9
  store i8 %19, ptr %9, align 1, !tbaa !9
  %20 = load i8, ptr %8, align 1, !tbaa !9
  %21 = zext i8 %20 to i32
  %22 = icmp eq i32 %21, 0
  br i1 %22, label %23, label %29

23:                                               ; preds = %13
  %24 = load i8, ptr %8, align 1, !tbaa !9
  %25 = zext i8 %24 to i32
  %26 = load i8, ptr %9, align 1, !tbaa !9
  %27 = zext i8 %26 to i32
  %28 = sub nsw i32 %25, %27
  store i32 %28, ptr %3, align 4
  store i32 1, ptr %10, align 4
  br label %42

29:                                               ; preds = %13
  br label %30

30:                                               ; preds = %29
  %31 = load i8, ptr %8, align 1, !tbaa !9
  %32 = zext i8 %31 to i32
  %33 = load i8, ptr %9, align 1, !tbaa !9
  %34 = zext i8 %33 to i32
  %35 = icmp eq i32 %32, %34
  br i1 %35, label %13, label %36, !llvm.loop !10

36:                                               ; preds = %30
  %37 = load i8, ptr %8, align 1, !tbaa !9
  %38 = zext i8 %37 to i32
  %39 = load i8, ptr %9, align 1, !tbaa !9
  %40 = zext i8 %39 to i32
  %41 = sub nsw i32 %38, %40
  store i32 %41, ptr %3, align 4
  store i32 1, ptr %10, align 4
  br label %42

42:                                               ; preds = %36, %23
  call void @llvm.lifetime.end.p0(i64 1, ptr %9) #2
  call void @llvm.lifetime.end.p0(i64 1, ptr %8) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %7) #2
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #2
  %43 = load i32, ptr %3, align 4
  ret i32 %43
}

; 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 = !{!"any pointer", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/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: nofree norecurse nosync nounwind memory(read, inaccessiblemem: none) uwtable
define dso_local range(i32 -255, 256) i32 @strcmp(ptr nocapture noundef readonly %0, ptr nocapture noundef readonly %1) local_unnamed_addr #0 {
  br label %3

3:                                                ; preds = %7, %2
  %.012 = phi ptr [ %1, %2 ], [ %8, %7 ]
  %.011 = phi ptr [ %0, %2 ], [ %9, %7 ]
  %4 = load i8, ptr %.011, align 1, !tbaa !5
  %5 = load i8, ptr %.012, align 1, !tbaa !5
  %6 = icmp eq i8 %4, 0
  br i1 %6, label %.loopexit, label %7

7:                                                ; preds = %3
  %8 = getelementptr inbounds i8, ptr %.012, i64 1
  %9 = getelementptr inbounds i8, ptr %.011, i64 1
  %10 = icmp eq i8 %4, %5
  br i1 %10, label %3, label %11, !llvm.loop !8

11:                                               ; preds = %7
  %12 = zext i8 %4 to i32
  br label %.loopexit

.loopexit:                                        ; preds = %3, %11
  %.sink = phi i32 [ %12, %11 ], [ 0, %3 ]
  %13 = zext i8 %5 to i32
  %14 = sub nsw i32 %.sink, %13
  ret i32 %14
}

attributes #0 = { nofree norecurse nosync nounwind 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/C++ TBAA"}
!8 = distinct !{!8, !9}
!9 = !{!"llvm.loop.mustprogress"}


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