; LLVM IR from guanzhi/GmSSL :: src (hex)

; 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: nounwind uwtable
define dso_local i32 @mem_is_zero(ptr noundef %0, i64 noundef %1) #1 {
  %3 = alloca ptr, align 8
  %4 = alloca i64, align 8
  %5 = alloca i32, align 4
  %6 = alloca i64, align 8
  store ptr %0, ptr %3, align 8, !tbaa !5
  store i64 %1, ptr %4, align 8, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %5) #2
  store i32 1, ptr %5, align 4, !tbaa !11
  call void @llvm.lifetime.start.p0(i64 8, ptr %6) #2
  store i64 0, ptr %6, align 8, !tbaa !9
  br label %7

7:                                                ; preds = %19, %2
  %8 = load i64, ptr %6, align 8, !tbaa !9
  %9 = load i64, ptr %4, align 8, !tbaa !9
  %10 = icmp ult i64 %8, %9
  br i1 %10, label %11, label %22

11:                                               ; preds = %7
  %12 = load ptr, ptr %3, align 8, !tbaa !5
  %13 = load i64, ptr %6, align 8, !tbaa !9
  %14 = getelementptr inbounds i8, ptr %12, i64 %13
  %15 = load i8, ptr %14, align 1, !tbaa !13
  %16 = icmp ne i8 %15, 0
  br i1 %16, label %17, label %18

17:                                               ; preds = %11
  store i32 0, ptr %5, align 4, !tbaa !11
  br label %18

18:                                               ; preds = %17, %11
  br label %19

19:                                               ; preds = %18
  %20 = load i64, ptr %6, align 8, !tbaa !9
  %21 = add i64 %20, 1
  store i64 %21, ptr %6, align 8, !tbaa !9
  br label %7, !llvm.loop !14

22:                                               ; preds = %7
  %23 = load i32, ptr %5, align 4, !tbaa !11
  call void @llvm.lifetime.end.p0(i64 8, ptr %6) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %5) #2
  ret i32 %23
}

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 = !{!"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 = !{!12, !12, i64 0}
!12 = !{!"int", !7, i64 0}
!13 = !{!7, !7, 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 range(i32 0, 2) i32 @mem_is_zero(ptr nocapture noundef readonly %0, i64 noundef %1) local_unnamed_addr #0 {
  %.not8 = icmp eq i64 %1, 0
  br i1 %.not8, label %._crit_edge, label %.lr.ph.preheader

.lr.ph.preheader:                                 ; preds = %2
  %min.iters.check = icmp ult i64 %1, 8
  br i1 %min.iters.check, label %.lr.ph.preheader12, label %vector.ph

vector.ph:                                        ; preds = %.lr.ph.preheader
  %n.vec = and i64 %1, -8
  br label %vector.body

vector.body:                                      ; preds = %vector.body, %vector.ph
  %index = phi i64 [ 0, %vector.ph ], [ %index.next, %vector.body ]
  %vec.phi = phi <4 x i1> [ zeroinitializer, %vector.ph ], [ %7, %vector.body ]
  %vec.phi9 = phi <4 x i1> [ zeroinitializer, %vector.ph ], [ %8, %vector.body ]
  %3 = getelementptr inbounds i8, ptr %0, i64 %index
  %4 = getelementptr inbounds i8, ptr %3, i64 4
  %wide.load = load <4 x i8>, ptr %3, align 1, !tbaa !5
  %wide.load10 = load <4 x i8>, ptr %4, align 1, !tbaa !5
  %5 = icmp ne <4 x i8> %wide.load, zeroinitializer
  %6 = icmp ne <4 x i8> %wide.load10, zeroinitializer
  %7 = or <4 x i1> %vec.phi, %5
  %8 = or <4 x i1> %vec.phi9, %6
  %index.next = add nuw i64 %index, 8
  %9 = icmp eq i64 %index.next, %n.vec
  br i1 %9, label %middle.block, label %vector.body, !llvm.loop !8

middle.block:                                     ; preds = %vector.body
  %bin.rdx = or <4 x i1> %8, %7
  %bin.rdx.fr = freeze <4 x i1> %bin.rdx
  %10 = bitcast <4 x i1> %bin.rdx.fr to i4
  %.not11 = icmp eq i4 %10, 0
  %rdx.select = zext i1 %.not11 to i32
  %cmp.n = icmp eq i64 %n.vec, %1
  br i1 %cmp.n, label %._crit_edge, label %.lr.ph.preheader12

.lr.ph.preheader12:                               ; preds = %middle.block, %.lr.ph.preheader
  %.07.ph = phi i64 [ 0, %.lr.ph.preheader ], [ %n.vec, %middle.block ]
  %.056.ph = phi i32 [ 1, %.lr.ph.preheader ], [ %rdx.select, %middle.block ]
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.preheader12, %.lr.ph
  %.07 = phi i64 [ %13, %.lr.ph ], [ %.07.ph, %.lr.ph.preheader12 ]
  %.056 = phi i32 [ %spec.select, %.lr.ph ], [ %.056.ph, %.lr.ph.preheader12 ]
  %11 = getelementptr inbounds i8, ptr %0, i64 %.07
  %12 = load i8, ptr %11, align 1, !tbaa !5
  %.not = icmp eq i8 %12, 0
  %spec.select = select i1 %.not, i32 %.056, i32 0
  %13 = add nuw i64 %.07, 1
  %exitcond.not = icmp eq i64 %13, %1
  br i1 %exitcond.not, label %._crit_edge, label %.lr.ph, !llvm.loop !12

._crit_edge:                                      ; preds = %.lr.ph, %middle.block, %2
  %.05.lcssa = phi i32 [ 1, %2 ], [ %rdx.select, %middle.block ], [ %spec.select, %.lr.ph ]
  ret i32 %.05.lcssa
}

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


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