; LLVM IR from google/esh :: examples/physical/nucleo-f401re/platform/uart (uart)

; 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 @uputc(i8 noundef signext %0) #0 {
  %2 = alloca i8, align 1
  store i8 %0, ptr %2, align 1, !tbaa !5
  br label %3

3:                                                ; preds = %9, %1
  %4 = load volatile i32, ptr inttoptr (i64 1073759232 to ptr), align 4, !tbaa !8
  %5 = lshr i32 %4, 7
  %6 = and i32 %5, 1
  %7 = icmp ne i32 %6, 0
  %8 = xor i1 %7, true
  br i1 %8, label %9, label %10

9:                                                ; preds = %3
  br label %3, !llvm.loop !10

10:                                               ; preds = %3
  %11 = load i8, ptr %2, align 1, !tbaa !5
  %12 = sext i8 %11 to i32
  store volatile i32 %12, ptr inttoptr (i64 1073759236 to ptr), align 4, !tbaa !8
  %13 = load i8, ptr %2, align 1, !tbaa !5
  %14 = sext i8 %13 to i32
  %15 = icmp eq i32 %14, 10
  br i1 %15, label %16, label %17

16:                                               ; preds = %10
  call void @uputc(i8 noundef signext 13)
  br label %17

17:                                               ; preds = %16, %10
  ret void
}

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)"}
!5 = !{!6, !6, i64 0}
!6 = !{!"omnipotent char", !7, i64 0}
!7 = !{!"Simple C/C++ TBAA"}
!8 = !{!9, !9, i64 0}
!9 = !{!"int", !6, i64 0}
!10 = distinct !{!10, !11}
!11 = !{!"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 nounwind uwtable
define dso_local void @uputc(i8 noundef signext %0) local_unnamed_addr #0 {
  br label %2

2:                                                ; preds = %2, %1
  %3 = load volatile i32, ptr inttoptr (i64 1073759232 to ptr), align 1024, !tbaa !5
  %4 = and i32 %3, 128
  %.not = icmp eq i32 %4, 0
  br i1 %.not, label %2, label %5, !llvm.loop !9

5:                                                ; preds = %2
  %6 = sext i8 %0 to i32
  store volatile i32 %6, ptr inttoptr (i64 1073759236 to ptr), align 4, !tbaa !5
  %7 = icmp eq i8 %0, 10
  br i1 %7, label %.preheader, label %10

.preheader:                                       ; preds = %5, %.preheader
  %8 = load volatile i32, ptr inttoptr (i64 1073759232 to ptr), align 1024, !tbaa !5
  %9 = and i32 %8, 128
  %.not.i = icmp eq i32 %9, 0
  br i1 %.not.i, label %.preheader, label %uputc.exit, !llvm.loop !9

uputc.exit:                                       ; preds = %.preheader
  store volatile i32 13, ptr inttoptr (i64 1073759236 to ptr), align 4, !tbaa !5
  br label %10

10:                                               ; preds = %uputc.exit, %5
  ret void
}

attributes #0 = { nofree norecurse 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)"}
!5 = !{!6, !6, i64 0}
!6 = !{!"int", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}
!9 = distinct !{!9, !10}
!10 = !{!"llvm.loop.mustprogress"}


; Effective O3 passes: EarlyCSEPass,GlobalOptPass,InferAlignmentPass,InlinerPass,InstCombinePass,LoopSimplifyPass,LoopUnrollPass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass