; LLVM IR from ubaldot/defrecs :: stm32f4x/ADC_Readings/Drivers/CMSIS/DSP/Examples/ARM/arm_convolution_example (q15)

; 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 void @arm_provide_guard_bits_q15(ptr noundef %0, i32 noundef %1, i32 noundef %2) #1 {
  %4 = alloca ptr, align 8
  %5 = alloca i32, align 4
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  store ptr %0, ptr %4, align 8, !tbaa !5
  store i32 %1, ptr %5, align 4, !tbaa !9
  store i32 %2, ptr %6, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #2
  store i32 0, ptr %7, align 4, !tbaa !9
  br label %8

8:                                                ; preds = %26, %3
  %9 = load i32, ptr %7, align 4, !tbaa !9
  %10 = load i32, ptr %5, align 4, !tbaa !9
  %11 = icmp ult i32 %9, %10
  br i1 %11, label %12, label %29

12:                                               ; preds = %8
  %13 = load ptr, ptr %4, align 8, !tbaa !5
  %14 = load i32, ptr %7, align 4, !tbaa !9
  %15 = zext i32 %14 to i64
  %16 = getelementptr inbounds i16, ptr %13, i64 %15
  %17 = load i16, ptr %16, align 2, !tbaa !11
  %18 = sext i16 %17 to i32
  %19 = load i32, ptr %6, align 4, !tbaa !9
  %20 = ashr i32 %18, %19
  %21 = trunc i32 %20 to i16
  %22 = load ptr, ptr %4, align 8, !tbaa !5
  %23 = load i32, ptr %7, align 4, !tbaa !9
  %24 = zext i32 %23 to i64
  %25 = getelementptr inbounds i16, ptr %22, i64 %24
  store i16 %21, ptr %25, align 2, !tbaa !11
  br label %26

26:                                               ; preds = %12
  %27 = load i32, ptr %7, align 4, !tbaa !9
  %28 = add i32 %27, 1
  store i32 %28, ptr %7, align 4, !tbaa !9
  br label %8, !llvm.loop !13

29:                                               ; preds = %8
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #2
  ret void
}

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 = !{!"int", !7, i64 0}
!11 = !{!12, !12, i64 0}
!12 = !{!"short", !7, i64 0}
!13 = distinct !{!13, !14}
!14 = !{!"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: readwrite) uwtable
define dso_local void @arm_provide_guard_bits_q15(ptr nocapture noundef %0, i32 noundef %1, i32 noundef %2) local_unnamed_addr #0 {
  %.not = icmp eq i32 %1, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph.preheader

.lr.ph.preheader:                                 ; preds = %3
  %wide.trip.count = zext i32 %1 to i64
  %min.iters.check = icmp ult i32 %1, 16
  br i1 %min.iters.check, label %.lr.ph.preheader10, label %vector.ph

vector.ph:                                        ; preds = %.lr.ph.preheader
  %n.vec = and i64 %wide.trip.count, 4294967280
  %broadcast.splatinsert = insertelement <8 x i32> poison, i32 %2, i64 0
  %broadcast.splat = shufflevector <8 x i32> %broadcast.splatinsert, <8 x i32> poison, <8 x i32> zeroinitializer
  br label %vector.body

vector.body:                                      ; preds = %vector.body, %vector.ph
  %index = phi i64 [ 0, %vector.ph ], [ %index.next, %vector.body ]
  %4 = getelementptr inbounds i16, ptr %0, i64 %index
  %5 = getelementptr inbounds i8, ptr %4, i64 16
  %wide.load = load <8 x i16>, ptr %4, align 2, !tbaa !5
  %wide.load9 = load <8 x i16>, ptr %5, align 2, !tbaa !5
  %6 = sext <8 x i16> %wide.load to <8 x i32>
  %7 = sext <8 x i16> %wide.load9 to <8 x i32>
  %8 = ashr <8 x i32> %6, %broadcast.splat
  %9 = ashr <8 x i32> %7, %broadcast.splat
  %10 = trunc nsw <8 x i32> %8 to <8 x i16>
  %11 = trunc nsw <8 x i32> %9 to <8 x i16>
  store <8 x i16> %10, ptr %4, align 2, !tbaa !5
  store <8 x i16> %11, ptr %5, align 2, !tbaa !5
  %index.next = add nuw i64 %index, 16
  %12 = icmp eq i64 %index.next, %n.vec
  br i1 %12, label %middle.block, label %vector.body, !llvm.loop !9

middle.block:                                     ; preds = %vector.body
  %cmp.n = icmp eq i64 %n.vec, %wide.trip.count
  br i1 %cmp.n, label %._crit_edge, label %.lr.ph.preheader10

.lr.ph.preheader10:                               ; preds = %middle.block, %.lr.ph.preheader
  %indvars.iv.ph = phi i64 [ 0, %.lr.ph.preheader ], [ %n.vec, %middle.block ]
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.preheader10, %.lr.ph
  %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ %indvars.iv.ph, %.lr.ph.preheader10 ]
  %13 = getelementptr inbounds i16, ptr %0, i64 %indvars.iv
  %14 = load i16, ptr %13, align 2, !tbaa !5
  %15 = sext i16 %14 to i32
  %16 = ashr i32 %15, %2
  %17 = trunc nsw i32 %16 to i16
  store i16 %17, ptr %13, align 2, !tbaa !5
  %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, label %.lr.ph, !llvm.loop !13

._crit_edge:                                      ; preds = %.lr.ph, %middle.block, %3
  ret void
}

attributes #0 = { nofree norecurse nosync nounwind 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, !6, i64 0}
!6 = !{!"short", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = distinct !{!9, !10, !11, !12}
!10 = !{!"llvm.loop.mustprogress"}
!11 = !{!"llvm.loop.isvectorized", i32 1}
!12 = !{!"llvm.loop.unroll.runtime.disable"}
!13 = distinct !{!13, !10, !12, !11}


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