; LLVM IR from devicehive/esp8266-firmware :: firmware-src/sources (rand)

; 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"

@seed = external hidden global i64, align 8

; Function Attrs: nounwind uwtable
define dso_local i32 @rand() #0 {
  %1 = load i64, ptr @seed, align 8, !tbaa !5
  %2 = icmp eq i64 %1, 0
  br i1 %2, label %3, label %6

3:                                                ; preds = %0
  %4 = call i32 @system_get_time()
  %5 = zext i32 %4 to i64
  store i64 %5, ptr @seed, align 8, !tbaa !5
  br label %6

6:                                                ; preds = %3, %0
  %7 = load i64, ptr @seed, align 8, !tbaa !5
  %8 = mul i64 %7, 1103515245
  %9 = add i64 %8, 12345
  store i64 %9, ptr @seed, align 8, !tbaa !5
  %10 = load i64, ptr @seed, align 8, !tbaa !5
  %11 = udiv i64 %10, 65536
  %12 = trunc i64 %11 to i32
  %13 = urem i32 %12, 32767
  ret i32 %13
}

declare i32 @system_get_time() #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 = { "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 = !{!"long", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}


; 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"

@seed = external hidden local_unnamed_addr global i64, align 8

; Function Attrs: nounwind uwtable
define dso_local range(i32 0, 32767) i32 @rand() local_unnamed_addr #0 {
  %1 = load i64, ptr @seed, align 8, !tbaa !5
  %2 = icmp eq i64 %1, 0
  br i1 %2, label %3, label %6

3:                                                ; preds = %0
  %4 = tail call i32 @system_get_time() #2
  %5 = zext i32 %4 to i64
  br label %6

6:                                                ; preds = %3, %0
  %7 = phi i64 [ %5, %3 ], [ %1, %0 ]
  %8 = mul i64 %7, 1103515245
  %9 = add i64 %8, 12345
  store i64 %9, ptr @seed, align 8, !tbaa !5
  %10 = lshr i64 %9, 16
  %11 = trunc i64 %10 to i32
  %12 = urem i32 %11, 32767
  ret i32 %12
}

declare i32 @system_get_time() local_unnamed_addr #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 = { "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 = !{!"long", !7, i64 0}
!7 = !{!"omnipotent char", !8, i64 0}
!8 = !{!"Simple C/C++ TBAA"}


; Effective O3 passes: DSEPass,EarlyCSEPass,GVNPass,GlobalOptPass,IPSCCPPass,InstCombinePass,TailCallElimPass