; LLVM IR from sca-secure-library-sca25519/sca25519 :: libopencm3/lib/lpc43xx (i2c)

; 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 @i2c0_tx_byte(i8 noundef zeroext %0) #0 {
  %2 = alloca i8, align 1
  store i8 %0, ptr %2, align 1, !tbaa !5
  %3 = load volatile i32, ptr inttoptr (i64 1074401280 to ptr), align 4, !tbaa !8
  %4 = and i32 %3, 32
  %5 = icmp ne i32 %4, 0
  br i1 %5, label %6, label %7

6:                                                ; preds = %1
  store volatile i32 32, ptr inttoptr (i64 1074401304 to ptr), align 4, !tbaa !8
  br label %7

7:                                                ; preds = %6, %1
  %8 = load i8, ptr %2, align 1, !tbaa !5
  %9 = zext i8 %8 to i32
  store volatile i32 %9, ptr inttoptr (i64 1074401288 to ptr), align 4, !tbaa !8
  store volatile i32 8, ptr inttoptr (i64 1074401304 to ptr), align 4, !tbaa !8
  br label %10

10:                                               ; preds = %15, %7
  %11 = load volatile i32, ptr inttoptr (i64 1074401280 to ptr), align 4, !tbaa !8
  %12 = and i32 %11, 8
  %13 = icmp ne i32 %12, 0
  %14 = xor i1 %13, true
  br i1 %14, label %15, label %16

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

16:                                               ; preds = %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 @i2c0_tx_byte(i8 noundef zeroext %0) local_unnamed_addr #0 {
  %2 = load volatile i32, ptr inttoptr (i64 1074401280 to ptr), align 4096, !tbaa !5
  %3 = and i32 %2, 32
  %.not = icmp eq i32 %3, 0
  br i1 %.not, label %5, label %4

4:                                                ; preds = %1
  store volatile i32 32, ptr inttoptr (i64 1074401304 to ptr), align 8, !tbaa !5
  br label %5

5:                                                ; preds = %4, %1
  %6 = zext i8 %0 to i32
  store volatile i32 %6, ptr inttoptr (i64 1074401288 to ptr), align 8, !tbaa !5
  store volatile i32 8, ptr inttoptr (i64 1074401304 to ptr), align 8, !tbaa !5
  br label %7

7:                                                ; preds = %7, %5
  %8 = load volatile i32, ptr inttoptr (i64 1074401280 to ptr), align 4096, !tbaa !5
  %9 = and i32 %8, 8
  %.not1 = icmp eq i32 %9, 0
  br i1 %.not1, label %7, label %10, !llvm.loop !9

10:                                               ; preds = %7
  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: GlobalOptPass,InferAlignmentPass,InstCombinePass,PostOrderFunctionAttrsPass,SROAPass,SimplifyCFGPass