; LLVM IR from devicehive/esp8266-firmware :: esp-utils/esp-flasher.ll (Z12esp_checksumPvj)

; 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 uwtable
define dso_local noundef i32 @_Z12esp_checksumPvj(ptr noundef %0, i32 noundef %1) #1 {
  %3 = alloca ptr, align 8
  %4 = alloca i32, align 4
  %5 = alloca i8, align 1
  %6 = alloca i32, align 4
  store ptr %0, ptr %3, align 8, !tbaa !5
  store i32 %1, ptr %4, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 1, ptr %5) #3
  store i8 -17, ptr %5, align 1, !tbaa !11
  call void @llvm.lifetime.start.p0(i64 4, ptr %6) #3
  store i32 0, ptr %6, align 4, !tbaa !9
  br label %7

7:                                                ; preds = %23, %2
  %8 = load i32, ptr %6, align 4, !tbaa !9
  %9 = load i32, ptr %4, align 4, !tbaa !9
  %10 = icmp ult i32 %8, %9
  br i1 %10, label %12, label %11

11:                                               ; preds = %7
  call void @llvm.lifetime.end.p0(i64 4, ptr %6) #3
  br label %26

12:                                               ; preds = %7
  %13 = load ptr, ptr %3, align 8, !tbaa !5
  %14 = load i32, ptr %6, align 4, !tbaa !9
  %15 = zext i32 %14 to i64
  %16 = getelementptr inbounds i8, ptr %13, i64 %15
  %17 = load i8, ptr %16, align 1, !tbaa !11
  %18 = zext i8 %17 to i32
  %19 = load i8, ptr %5, align 1, !tbaa !11
  %20 = zext i8 %19 to i32
  %21 = xor i32 %20, %18
  %22 = trunc i32 %21 to i8
  store i8 %22, ptr %5, align 1, !tbaa !11
  br label %23

23:                                               ; preds = %12
  %24 = load i32, ptr %6, align 4, !tbaa !9
  %25 = add i32 %24, 1
  store i32 %25, ptr %6, align 4, !tbaa !9
  br label %7, !llvm.loop !12

26:                                               ; preds = %11
  %27 = load i8, ptr %5, align 1, !tbaa !11
  %28 = zext i8 %27 to i32
  %29 = call noundef i32 @_ZL17__uint32_identityj(i32 noundef %28)
  call void @llvm.lifetime.end.p0(i64 1, ptr %5) #3
  ret i32 %29
}

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare hidden noundef i32 @_ZL17__uint32_identityj(i32 noundef) #2

attributes #0 = { nocallback nofree nosync nounwind willreturn memory(argmem: readwrite) }
attributes #1 = { mustprogress 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 = { inlinehint 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 #3 = { 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 = !{!10, !10, i64 0}
!10 = !{!"int", !7, i64 0}
!11 = !{!7, !7, i64 0}
!12 = distinct !{!12, !13}
!13 = !{!"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 nounwind uwtable
define dso_local noundef i32 @_Z12esp_checksumPvj(ptr nocapture noundef readonly %0, i32 noundef %1) local_unnamed_addr #0 {
  %.not = icmp eq i32 %1, 0
  br i1 %.not, label %._crit_edge, label %iter.check

iter.check:                                       ; preds = %2
  %wide.trip.count = zext i32 %1 to i64
  %min.iters.check = icmp ult i32 %1, 8
  br i1 %min.iters.check, label %.lr.ph.preheader, label %vector.main.loop.iter.check

vector.main.loop.iter.check:                      ; preds = %iter.check
  %min.iters.check9 = icmp ult i32 %1, 32
  br i1 %min.iters.check9, label %vec.epilog.ph, label %vector.ph

vector.ph:                                        ; preds = %vector.main.loop.iter.check
  %n.vec = and i64 %wide.trip.count, 4294967264
  br label %vector.body

vector.body:                                      ; preds = %vector.body, %vector.ph
  %index = phi i64 [ 0, %vector.ph ], [ %index.next, %vector.body ]
  %vec.phi = phi <16 x i8> [ <i8 -17, i8 0, i8 0, i8 0, i8 0, i8 0, i8 0, i8 0, i8 0, i8 0, i8 0, i8 0, i8 0, i8 0, i8 0, i8 0>, %vector.ph ], [ %5, %vector.body ]
  %vec.phi10 = phi <16 x i8> [ zeroinitializer, %vector.ph ], [ %6, %vector.body ]
  %3 = getelementptr inbounds i8, ptr %0, i64 %index
  %4 = getelementptr inbounds i8, ptr %3, i64 16
  %wide.load = load <16 x i8>, ptr %3, align 1, !tbaa !5
  %wide.load11 = load <16 x i8>, ptr %4, align 1, !tbaa !5
  %5 = xor <16 x i8> %wide.load, %vec.phi
  %6 = xor <16 x i8> %wide.load11, %vec.phi10
  %index.next = add nuw i64 %index, 32
  %7 = icmp eq i64 %index.next, %n.vec
  br i1 %7, label %middle.block, label %vector.body, !llvm.loop !8

middle.block:                                     ; preds = %vector.body
  %bin.rdx = xor <16 x i8> %6, %5
  %8 = tail call i8 @llvm.vector.reduce.xor.v16i8(<16 x i8> %bin.rdx)
  %cmp.n = icmp eq i64 %n.vec, %wide.trip.count
  br i1 %cmp.n, label %._crit_edge.loopexit, label %vec.epilog.iter.check

vec.epilog.iter.check:                            ; preds = %middle.block
  %n.vec.remaining = and i64 %wide.trip.count, 24
  %min.epilog.iters.check = icmp eq i64 %n.vec.remaining, 0
  br i1 %min.epilog.iters.check, label %.lr.ph.preheader, label %vec.epilog.ph

.lr.ph.preheader:                                 ; preds = %vec.epilog.middle.block, %iter.check, %vec.epilog.iter.check
  %indvars.iv.ph = phi i64 [ 0, %iter.check ], [ %n.vec, %vec.epilog.iter.check ], [ %n.vec13, %vec.epilog.middle.block ]
  %.067.ph = phi i8 [ -17, %iter.check ], [ %8, %vec.epilog.iter.check ], [ %13, %vec.epilog.middle.block ]
  br label %.lr.ph

vec.epilog.ph:                                    ; preds = %vector.main.loop.iter.check, %vec.epilog.iter.check
  %bc.merge.rdx = phi i8 [ %8, %vec.epilog.iter.check ], [ -17, %vector.main.loop.iter.check ]
  %vec.epilog.resume.val = phi i64 [ %n.vec, %vec.epilog.iter.check ], [ 0, %vector.main.loop.iter.check ]
  %n.vec13 = and i64 %wide.trip.count, 4294967288
  %9 = insertelement <8 x i8> <i8 poison, i8 0, i8 0, i8 0, i8 0, i8 0, i8 0, i8 0>, i8 %bc.merge.rdx, i64 0
  br label %vec.epilog.vector.body

vec.epilog.vector.body:                           ; preds = %vec.epilog.vector.body, %vec.epilog.ph
  %index14 = phi i64 [ %vec.epilog.resume.val, %vec.epilog.ph ], [ %index.next17, %vec.epilog.vector.body ]
  %vec.phi15 = phi <8 x i8> [ %9, %vec.epilog.ph ], [ %11, %vec.epilog.vector.body ]
  %10 = getelementptr inbounds i8, ptr %0, i64 %index14
  %wide.load16 = load <8 x i8>, ptr %10, align 1, !tbaa !5
  %11 = xor <8 x i8> %wide.load16, %vec.phi15
  %index.next17 = add nuw i64 %index14, 8
  %12 = icmp eq i64 %index.next17, %n.vec13
  br i1 %12, label %vec.epilog.middle.block, label %vec.epilog.vector.body, !llvm.loop !12

vec.epilog.middle.block:                          ; preds = %vec.epilog.vector.body
  %13 = tail call i8 @llvm.vector.reduce.xor.v8i8(<8 x i8> %11)
  %cmp.n18 = icmp eq i64 %n.vec13, %wide.trip.count
  br i1 %cmp.n18, label %._crit_edge.loopexit, label %.lr.ph.preheader

._crit_edge.loopexit:                             ; preds = %.lr.ph, %vec.epilog.middle.block, %middle.block
  %.lcssa = phi i8 [ %8, %middle.block ], [ %13, %vec.epilog.middle.block ], [ %18, %.lr.ph ]
  %14 = zext i8 %.lcssa to i32
  br label %._crit_edge

._crit_edge:                                      ; preds = %._crit_edge.loopexit, %2
  %.06.lcssa = phi i32 [ 239, %2 ], [ %14, %._crit_edge.loopexit ]
  %15 = tail call noundef i32 @_ZL17__uint32_identityj(i32 noundef %.06.lcssa)
  ret i32 %15

.lr.ph:                                           ; preds = %.lr.ph.preheader, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ %indvars.iv.ph, %.lr.ph.preheader ]
  %.067 = phi i8 [ %18, %.lr.ph ], [ %.067.ph, %.lr.ph.preheader ]
  %16 = getelementptr inbounds i8, ptr %0, i64 %indvars.iv
  %17 = load i8, ptr %16, align 1, !tbaa !5
  %18 = xor i8 %17, %.067
  %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.loopexit, label %.lr.ph, !llvm.loop !13
}

; Function Attrs: inlinehint mustprogress nounwind uwtable
declare hidden noundef i32 @_ZL17__uint32_identityj(i32 noundef) local_unnamed_addr #1

; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare i8 @llvm.vector.reduce.xor.v16i8(<16 x i8>) #2

; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
declare i8 @llvm.vector.reduce.xor.v8i8(<8 x i8>) #2

attributes #0 = { 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 #1 = { inlinehint 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 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }

!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"}
!8 = distinct !{!8, !9, !10, !11}
!9 = !{!"llvm.loop.mustprogress"}
!10 = !{!"llvm.loop.isvectorized", i32 1}
!11 = !{!"llvm.loop.unroll.runtime.disable"}
!12 = distinct !{!12, !9, !10, !11}
!13 = distinct !{!13, !9, !11, !10}


; Effective O3 passes: CorrelatedValuePropagationPass,GVNPass,GlobalOptPass,IPSCCPPass,IndVarSimplifyPass,InferFunctionAttrsPass,InstCombinePass,InstSimplifyPass,LCSSAPass,LoopLoadEliminationPass,LoopRotatePass,LoopSimplifyPass,LoopUnrollPass,LoopVectorizePass,PostOrderFunctionAttrsPass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass