; LLVM IR from thalium/icebox :: third_party/virtualbox/src/VBox/Devices/EFI/Firmware/OptionRomPkg (I2cReceiveByte)

; 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
declare dso_local zeroext i8 @I2cPinRead(ptr noundef, i8 noundef zeroext) #1

; Function Attrs: nounwind uwtable
declare dso_local void @I2cPinWrite(ptr noundef, i8 noundef zeroext, i8 noundef zeroext) #1

; Function Attrs: nounwind uwtable
declare dso_local void @I2cDelay() #1

; Function Attrs: nounwind uwtable
define dso_local zeroext i8 @I2cReceiveByte(ptr noundef %0) #1 {
  %2 = alloca ptr, align 8
  %3 = alloca i8, align 1
  %4 = alloca i64, align 8
  store ptr %0, ptr %2, align 8, !tbaa !5
  call void @llvm.lifetime.start.p0(i64 1, ptr %3) #2
  call void @llvm.lifetime.start.p0(i64 8, ptr %4) #2
  store i8 0, ptr %3, align 1, !tbaa !9
  store i64 0, ptr %4, align 8, !tbaa !10
  br label %5

5:                                                ; preds = %22, %1
  %6 = load i64, ptr %4, align 8, !tbaa !10
  %7 = icmp ult i64 %6, 8
  br i1 %7, label %8, label %25

8:                                                ; preds = %5
  %9 = load ptr, ptr %2, align 8, !tbaa !5
  call void @I2cPinWrite(ptr noundef %9, i8 noundef zeroext 0, i8 noundef zeroext 1)
  call void @I2cDelay()
  %10 = load i8, ptr %3, align 1, !tbaa !9
  %11 = zext i8 %10 to i32
  %12 = shl i32 %11, 1
  %13 = trunc i32 %12 to i8
  store i8 %13, ptr %3, align 1, !tbaa !9
  %14 = load i8, ptr %3, align 1, !tbaa !9
  %15 = zext i8 %14 to i32
  %16 = load ptr, ptr %2, align 8, !tbaa !5
  %17 = call zeroext i8 @I2cPinRead(ptr noundef %16, i8 noundef zeroext 7)
  %18 = zext i8 %17 to i32
  %19 = or i32 %15, %18
  %20 = trunc i32 %19 to i8
  store i8 %20, ptr %3, align 1, !tbaa !9
  %21 = load ptr, ptr %2, align 8, !tbaa !5
  call void @I2cPinWrite(ptr noundef %21, i8 noundef zeroext 0, i8 noundef zeroext 0)
  br label %22

22:                                               ; preds = %8
  %23 = load i64, ptr %4, align 8, !tbaa !10
  %24 = add i64 %23, -1
  store i64 %24, ptr %4, align 8, !tbaa !10
  br label %5, !llvm.loop !12

25:                                               ; preds = %5
  %26 = load i8, ptr %3, align 1, !tbaa !9
  call void @llvm.lifetime.end.p0(i64 8, ptr %4) #2
  call void @llvm.lifetime.end.p0(i64 1, ptr %3) #2
  ret i8 %26
}

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 = !{!7, !7, i64 0}
!10 = !{!11, !11, i64 0}
!11 = !{!"long long", !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: nounwind uwtable
declare dso_local zeroext i8 @I2cPinRead(ptr noundef, i8 noundef zeroext) local_unnamed_addr #0

; Function Attrs: nounwind uwtable
declare dso_local void @I2cPinWrite(ptr noundef, i8 noundef zeroext, i8 noundef zeroext) local_unnamed_addr #0

; Function Attrs: nounwind uwtable
declare dso_local void @I2cDelay() local_unnamed_addr #0

; Function Attrs: nounwind uwtable
define dso_local zeroext i8 @I2cReceiveByte(ptr noundef %0) local_unnamed_addr #0 {
  tail call void @I2cPinWrite(ptr noundef %0, i8 noundef zeroext 0, i8 noundef zeroext 1)
  tail call void @I2cDelay()
  %2 = tail call zeroext i8 @I2cPinRead(ptr noundef %0, i8 noundef zeroext 7)
  tail call void @I2cPinWrite(ptr noundef %0, i8 noundef zeroext 0, i8 noundef zeroext 0)
  ret i8 %2
}

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" }

!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)"}


; Effective O3 passes: GlobalOptPass,IPSCCPPass,InferFunctionAttrsPass,InstCombinePass,LCSSAPass,LoopRotatePass,ReassociatePass,SROAPass,SimplifyCFGPass,TailCallElimPass