Incorrect derivative on -O0

[timkaler]

; ModuleID = 'silent_failure.c'
source_filename = "silent_failure.c"
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"

$_ZSt4fabsf = comdat any

@.str = private unnamed_addr constant [36 x i8] c"hello! %f, res2 %f, da: %f, db: %f\0A\00", align 1

; Function Attrs: noinline optnone uwtable
define dso_local void @compute_sumabs(float* %a, float* %b, float* %ret) #0 {
entry:
  %a.addr = alloca float*, align 8
  %b.addr = alloca float*, align 8
  %ret.addr = alloca float*, align 8
  store float* %a, float** %a.addr, align 8
  store float* %b, float** %b.addr, align 8
  store float* %ret, float** %ret.addr, align 8
  %0 = load float*, float** %a.addr, align 8
  %1 = load float, float* %0, align 4
  %call = call float @_ZSt4fabsf(float %1)
  %2 = load float*, float** %b.addr, align 8
  %3 = load float, float* %2, align 4
  %call1 = call float @_ZSt4fabsf(float %3)
  %add = fadd float %call, %call1
  %4 = load float*, float** %ret.addr, align 8
  store float %add, float* %4, align 4
  ret void
}

; Function Attrs: noinline nounwind optnone uwtable
define linkonce_odr dso_local float @_ZSt4fabsf(float %__x) #1 comdat {
entry:
  %__x.addr = alloca float, align 4
  store float %__x, float* %__x.addr, align 4
  %0 = load float, float* %__x.addr, align 4
  %1 = call float @llvm.fabs.f32(float %0)
  ret float %1
}

; Function Attrs: noinline norecurse optnone uwtable
define dso_local i32 @main(i32 %argc, i8** %argv) #2 {
entry:
  %retval = alloca i32, align 4
  %argc.addr = alloca i32, align 4
  %argv.addr = alloca i8**, align 8
  %a = alloca float, align 4
  %b = alloca float, align 4
  %da = alloca float, align 4
  %db = alloca float, align 4
  %ret = alloca float, align 4
  %dret = alloca float, align 4
  store i32 0, i32* %retval, align 4
  store i32 %argc, i32* %argc.addr, align 4
  store i8** %argv, i8*** %argv.addr, align 8
  store float 2.000000e+00, float* %a, align 4
  store float 3.000000e+00, float* %b, align 4
  store float 0.000000e+00, float* %da, align 4
  store float 0.000000e+00, float* %db, align 4
  store float 0.000000e+00, float* %ret, align 4
  store float 1.000000e+00, float* %dret, align 4
  call void @compute_sumabs(float* %a, float* %b, float* %ret)
  %0 = call double (...) @__enzyme_autodiff.f64(void (float*, float*, float*)* @compute_sumabs, float* %a, float* %da, float* %b, float* %db, float* %ret, float* %dret)
  %1 = load float, float* %ret, align 4
  %conv = fpext float %1 to double
  %2 = load float, float* %ret, align 4
  %conv1 = fpext float %2 to double
  %3 = load float, float* %da, align 4
  %conv2 = fpext float %3 to double
  %4 = load float, float* %db, align 4
  %conv3 = fpext float %4 to double
  %call = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([36 x i8], [36 x i8]* @.str, i32 0, i32 0), double %conv, double %conv1, double %conv2, double %conv3)
  ret i32 0
}

declare double @__enzyme_autodiff.f64(...)

declare dso_local i32 @printf(i8*, ...) #3

; Function Attrs: nounwind readnone speculatable
declare float @llvm.fabs.f32(float) #4

attributes #0 = { noinline optnone uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #1 = { noinline nounwind optnone uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #2 = { noinline norecurse optnone uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #3 = { "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #4 = { nounwind readnone speculatable }

!llvm.module.flags = !{!0}
!llvm.ident = !{!1}

!0 = !{i32 1, !"wchar_size", i32 4}
!1 = !{!"clang version 7.1.0 "}