; LLVM IR from FedericaPaoli1/stm32-speech-recognition-and-traduction :: Drivers/CMSIS/DSP/Source/SupportFunctions (arm_q31_to_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: nounwind uwtable
define dso_local void @arm_q31_to_q15(ptr noundef %0, ptr noundef %1, i32 noundef %2) #0 {
  %4 = alloca ptr, align 8
  %5 = alloca ptr, align 8
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  %8 = alloca ptr, align 8
  store ptr %0, ptr %4, align 8, !tbaa !5
  store ptr %1, ptr %5, align 8, !tbaa !5
  store i32 %2, ptr %6, align 4, !tbaa !9
  call void @llvm.lifetime.start.p0(i64 4, ptr %7) #2
  call void @llvm.lifetime.start.p0(i64 8, ptr %8) #2
  %9 = load ptr, ptr %4, align 8, !tbaa !5
  store ptr %9, ptr %8, align 8, !tbaa !5
  %10 = load i32, ptr %6, align 4, !tbaa !9
  store i32 %10, ptr %7, align 4, !tbaa !9
  br label %11

11:                                               ; preds = %14, %3
  %12 = load i32, ptr %7, align 4, !tbaa !9
  %13 = icmp ugt i32 %12, 0
  br i1 %13, label %14, label %24

14:                                               ; preds = %11
  %15 = load ptr, ptr %8, align 8, !tbaa !5
  %16 = getelementptr inbounds i32, ptr %15, i32 1
  store ptr %16, ptr %8, align 8, !tbaa !5
  %17 = load i32, ptr %15, align 4, !tbaa !9
  %18 = ashr i32 %17, 16
  %19 = trunc i32 %18 to i16
  %20 = load ptr, ptr %5, align 8, !tbaa !5
  %21 = getelementptr inbounds i16, ptr %20, i32 1
  store ptr %21, ptr %5, align 8, !tbaa !5
  store i16 %19, ptr %20, align 2, !tbaa !11
  %22 = load i32, ptr %7, align 4, !tbaa !9
  %23 = add i32 %22, -1
  store i32 %23, ptr %7, align 4, !tbaa !9
  br label %11, !llvm.loop !13

24:                                               ; preds = %11
  call void @llvm.lifetime.end.p0(i64 8, ptr %8) #2
  call void @llvm.lifetime.end.p0(i64 4, ptr %7) #2
  ret void
}

; 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 = !{!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(readwrite, inaccessiblemem: none) uwtable
define dso_local void @arm_q31_to_q15(ptr nocapture noundef readonly %0, ptr nocapture noundef writeonly %1, i32 noundef %2) local_unnamed_addr #0 {
  %.not7 = icmp eq i32 %2, 0
  br i1 %.not7, label %._crit_edge, label %.lr.ph.preheader

.lr.ph.preheader:                                 ; preds = %3
  %4 = zext i32 %2 to i64
  %min.iters.check = icmp ult i32 %2, 8
  br i1 %min.iters.check, label %.lr.ph.preheader20, label %vector.ph

vector.ph:                                        ; preds = %.lr.ph.preheader
  %n.vec = and i64 %4, 4294967288
  %5 = shl nuw nsw i64 %n.vec, 2
  %ind.end = getelementptr i8, ptr %0, i64 %5
  %.cast = trunc nuw i64 %n.vec to i32
  %ind.end11 = sub i32 %2, %.cast
  %6 = shl nuw nsw i64 %n.vec, 1
  %ind.end13 = getelementptr i8, ptr %1, i64 %6
  br label %vector.body

vector.body:                                      ; preds = %vector.body, %vector.ph
  %index = phi i64 [ 0, %vector.ph ], [ %index.next, %vector.body ]
  %offset.idx = shl i64 %index, 2
  %next.gep = getelementptr i8, ptr %0, i64 %offset.idx
  %offset.idx16 = shl i64 %index, 1
  %next.gep17 = getelementptr i8, ptr %1, i64 %offset.idx16
  %7 = getelementptr i8, ptr %next.gep, i64 16
  %wide.load = load <4 x i32>, ptr %next.gep, align 4, !tbaa !5
  %wide.load19 = load <4 x i32>, ptr %7, align 4, !tbaa !5
  %8 = lshr <4 x i32> %wide.load, <i32 16, i32 16, i32 16, i32 16>
  %9 = lshr <4 x i32> %wide.load19, <i32 16, i32 16, i32 16, i32 16>
  %10 = trunc nuw <4 x i32> %8 to <4 x i16>
  %11 = trunc nuw <4 x i32> %9 to <4 x i16>
  %12 = getelementptr i8, ptr %next.gep17, i64 8
  store <4 x i16> %10, ptr %next.gep17, align 2, !tbaa !9
  store <4 x i16> %11, ptr %12, align 2, !tbaa !9
  %index.next = add nuw i64 %index, 8
  %13 = icmp eq i64 %index.next, %n.vec
  br i1 %13, label %middle.block, label %vector.body, !llvm.loop !11

middle.block:                                     ; preds = %vector.body
  %cmp.n = icmp eq i64 %n.vec, %4
  br i1 %cmp.n, label %._crit_edge, label %.lr.ph.preheader20

.lr.ph.preheader20:                               ; preds = %middle.block, %.lr.ph.preheader
  %.010.ph = phi ptr [ %0, %.lr.ph.preheader ], [ %ind.end, %middle.block ]
  %.059.ph = phi i32 [ %2, %.lr.ph.preheader ], [ %ind.end11, %middle.block ]
  %.068.ph = phi ptr [ %1, %.lr.ph.preheader ], [ %ind.end13, %middle.block ]
  br label %.lr.ph

.lr.ph:                                           ; preds = %.lr.ph.preheader20, %.lr.ph
  %.010 = phi ptr [ %14, %.lr.ph ], [ %.010.ph, %.lr.ph.preheader20 ]
  %.059 = phi i32 [ %19, %.lr.ph ], [ %.059.ph, %.lr.ph.preheader20 ]
  %.068 = phi ptr [ %18, %.lr.ph ], [ %.068.ph, %.lr.ph.preheader20 ]
  %14 = getelementptr inbounds i8, ptr %.010, i64 4
  %15 = load i32, ptr %.010, align 4, !tbaa !5
  %16 = lshr i32 %15, 16
  %17 = trunc nuw i32 %16 to i16
  %18 = getelementptr inbounds i8, ptr %.068, i64 2
  store i16 %17, ptr %.068, align 2, !tbaa !9
  %19 = add i32 %.059, -1
  %.not = icmp eq i32 %19, 0
  br i1 %.not, label %._crit_edge, label %.lr.ph, !llvm.loop !15

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

attributes #0 = { nofree norecurse nosync nounwind memory(readwrite, 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 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = !{!10, !10, i64 0}
!10 = !{!"short", !7, i64 0}
!11 = distinct !{!11, !12, !13, !14}
!12 = !{!"llvm.loop.mustprogress"}
!13 = !{!"llvm.loop.isvectorized", i32 1}
!14 = !{!"llvm.loop.unroll.runtime.disable"}
!15 = distinct !{!15, !12, !14, !13}


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