LLVM 16: Opaque pointer failure at rustc

[bytesnake]

Part of #29.

#[autodiff(cos_inplace, Reverse, Const)]
fn sin_inplace(#[dup] x: &f32, #[dup_noneed] y: &mut f32) {
    *y = x.sin();
}

Results in:

rustc: /home/losch/Documents/rust-ml/rustc2/src/llvm-project/llvm/include/llvm/IR/Type.h:418: llvm::Type* llvm::Type::getNonOpaquePointerElementType() const: Assertion `NumContainedTys && "Attempting to get element type of opaque pointer"' failed.

I'm currently rebuilding LLVM with RelWithDebInfo for more information, here is a preliminary trace:

after simplification :
; Function Attrs: mustprogress nofree noinline nosync nounwind nonlazybind willreturn memory(argmem: readwrite) uwtable
define internal void @preprocess__ZN3sin11sin_inplace17h49beadd84ee4eb97E(ptr noalias nocapture noundef readonly align 4 dereferenceable(4) %0, ptr noalias nocapture noundef writeonly align 4 dereferenceable(4) %1) unnamed_addr EnzymeAD/Enzyme#1 {
  %3 = load float, ptr %0, align 4, !noundef !4
  %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100
  store float %4, ptr %1, align 4
  ret void
}

in new function diffe_ZN3sin11sin_inplace17h49beadd84ee4eb97E nonconstant arg ptr %0
in new function diffe_ZN3sin11sin_inplace17h49beadd84ee4eb97E nonconstant arg ptr %2
analyzing function preprocess__ZN3sin11sin_inplace17h49beadd84ee4eb97E
 + knowndata: ptr %0 : {[-1]:Pointer, [-1,-1]:Float@float} - {}
 + knowndata: ptr %1 : {[-1]:Pointer, [-1,-1]:Float@float} - {}
 + retdata: {}
updating analysis of val: ptr %0 current: {} new {[-1]:Pointer, [-1,-1]:Float@float} from ptr %0 Changed=1 legal=1
updating analysis of val: ptr %1 current: {} new {[-1]:Pointer, [-1,-1]:Float@float} from ptr %1 Changed=1 legal=1
updating analysis of val: ptr %0 current: {[-1]:Pointer, [-1,-1]:Float@float} new {[-1]:Pointer, [-1,-1]:Float@float} from ptr %0 Changed=0 legal=1
updating analysis of val: ptr %1 current: {[-1]:Pointer, [-1,-1]:Float@float} new {[-1]:Pointer, [-1,-1]:Float@float} from ptr %1 Changed=0 legal=1
updating analysis of val: ptr %0 current: {[-1]:Pointer, [-1,-1]:Float@float} new {[-1]:Pointer} from   %3 = load float, ptr %0, align 4, !noundef !4 Changed=0 legal=1
updating analysis of val:   %3 = load float, ptr %0, align 4, !noundef !4 current: {} new {[-1]:Float@float} from   %3 = load float, ptr %0, align 4, !noundef !4 Changed=1 legal=1
updating analysis of val:   %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100 current: {} new {[-1]:Float@float} from   %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100 Changed=1 legal=1
updating analysis of val:   %3 = load float, ptr %0, align 4, !noundef !4 current: {[-1]:Float@float} new {[-1]:Float@float} from   %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100 Changed=0 legal=1
updating analysis of val: ptr %1 current: {[-1]:Pointer, [-1,-1]:Float@float} new {[-1]:Pointer, [-1,0]:Float@float} from   store float %4, ptr %1, align 4 Changed=0 legal=1
updating analysis of val:   %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100 current: {[-1]:Float@float} new {[-1]:Float@float} from   store float %4, ptr %1, align 4 Changed=0 legal=1
updating analysis of val: ptr %0 current: {[-1]:Pointer, [-1,-1]:Float@float} new {[-1]:Pointer, [-1,0]:Float@float} from   %3 = load float, ptr %0, align 4, !noundef !4 Changed=0 legal=1
updating analysis of val:   %3 = load float, ptr %0, align 4, !noundef !4 current: {[-1]:Float@float} new {[-1]:Float@float} from   %3 = load float, ptr %0, align 4, !noundef !4 Changed=0 legal=1
checking if is constant[3]   %3 = load float, ptr %0, align 4, !noundef !4
 < UPSEARCH1>  %3 = load float, ptr %0, align 4, !noundef !4
nonconstant(1)  up-inst   %3 = load float, ptr %0, align 4, !noundef !4 op ptr %0
 <Value USESEARCH2>  %3 = load float, ptr %0, align 4, !noundef !4 UA=None
      considering use of   %3 = load float, ptr %0, align 4, !noundef !4 -   %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100
      considering use of   %3 = load float, ptr %0, align 4, !noundef !4 -   store float %4, ptr %1, align 4
Value nonconstant inst (uses):  %3 = load float, ptr %0, align 4, !noundef !4 user   store float %4, ptr %1, align 4
 </Value USESEARCH2 const=0>  %3 = load float, ptr %0, align 4, !noundef !4
 Value nonconstant (couldn't disprove)[3]  %3 = load float, ptr %0, align 4, !noundef !4
 <Value USESEARCH2>  %3 = load float, ptr %0, align 4, !noundef !4 UA=None
      considering use of   %3 = load float, ptr %0, align 4, !noundef !4 -   %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100
      considering use of   %3 = load float, ptr %0, align 4, !noundef !4 -   store float %4, ptr %1, align 4
Value nonconstant inst (uses):  %3 = load float, ptr %0, align 4, !noundef !4 user   store float %4, ptr %1, align 4
 </Value USESEARCH2 const=0>  %3 = load float, ptr %0, align 4, !noundef !4
 < UPSEARCH1>  %3 = load float, ptr %0, align 4, !noundef !4
nonconstant(1)  up-inst   %3 = load float, ptr %0, align 4, !noundef !4 op ptr %0
couldnt decide fallback as nonconstant instruction(3):  %3 = load float, ptr %0, align 4, !noundef !4
  %3 = load float, ptr %0, align 4, !noundef !4 cv=0 ci=0
checking if is constant[3]   %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100
 < UPSEARCH1>  %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100
nonconstant(1)  up-call   %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100 op   %3 = load float, ptr %0, align 4, !noundef !4
 <Value USESEARCH2>  %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100 UA=None
      considering use of   %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100 -   store float %4, ptr %1, align 4
Value nonconstant inst (uses):  %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100 user   store float %4, ptr %1, align 4
 </Value USESEARCH2 const=0>  %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100
 Value nonconstant (couldn't disprove)[3]  %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100
 <Value USESEARCH2>  %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100 UA=None
      considering use of   %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100 -   store float %4, ptr %1, align 4
Value nonconstant inst (uses):  %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100 user   store float %4, ptr %1, align 4
 </Value USESEARCH2 const=0>  %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100
 < UPSEARCH1>  %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100
nonconstant(1)  up-call   %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100 op   %3 = load float, ptr %0, align 4, !noundef !4
couldnt decide fallback as nonconstant instruction(3):  %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100
  %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100 cv=0 ci=0
checking if is constant[3]   store float %4, ptr %1, align 4
 < UPSEARCH1>  store float %4, ptr %1, align 4
nonconstant(1)  up-inst   store float %4, ptr %1, align 4 op   %4 = tail call float @llvm.sin.f32(float %3) EnzymeAD/Enzyme#100
couldnt decide fallback as nonconstant instruction(3):  store float %4, ptr %1, align 4
  store float %4, ptr %1, align 4 cv=1 ci=0
  ret void cv=1 ci=1
; Function Attrs: mustprogress nofree noinline nosync nounwind nonlazybind willreturn memory(argmem: readwrite) uwtable
define internal void @diffe_ZN3sin11sin_inplace17h49beadd84ee4eb97E(ptr noalias nocapture noundef readonly align 4 dereferenceable(4) %0, ptr nocapture %1, ptr noalias nocapture writeonly align 4 dereferenceable(4) %2, ptr nocapture %3) unnamed_addr EnzymeAD/Enzyme#1 {
  %5 = load float, ptr %0, align 4, !alias.scope !47843, !noalias !47846, !noundef !4
  %6 = load float, ptr %3, align 4, !alias.scope !47848, !noalias !47851
  store float 0.000000e+00, ptr %3, align 4, !alias.scope !47848, !noalias !47851
  %7 = call fast float @llvm.cos.f32(float %5)
  %8 = fmul fast float %6, %7
  %9 = load float, ptr %1, align 4, !alias.scope !47846, !noalias !47843
  %10 = fadd fast float %9, %8
  store float %10, ptr %1, align 4, !alias.scope !47846, !noalias !47843
  ret void
}

[wsmoses]

can you show the backtrace of the error assertion.

[bytesnake]

got none but I'm rebuilding with RelWithDebInfo now, or do I need to activate something else?

[ZuseZ4]

That should be enough. Pure Debug build would probably be even slightly better since we have small testcases, but both should work I think.

[wsmoses]

Yeah I just need to see what line of Enzyme code triggers it.

[bytesnake]

Setting RelWithDebInfo or debug mode did not help, I will rebuild the compiler from scratch

[bytesnake]

EnzymeAD/Enzyme#4  0x00007fffe74b99f8 in llvm::Type::getNonOpaquePointerElementType (this=0x7fffdc627bd0)
    at /home/losch/Documents/rust-ml/rustc2/src/llvm-project/llvm/include/llvm/IR/Type.h:418
EnzymeAD/Enzyme#5  0x00007fffe75d1c16 in LLVMGetElementType (WrappedTy=0x7fffdc627bd0)
    at /home/losch/Documents/rust-ml/rustc2/src/llvm-project/llvm/lib/IR/Core.cpp:815
EnzymeAD/Enzyme#6  0x00007ffff464d45a in _RNvNtNtCs8k9sJ7haxZX_18rustc_codegen_llvm4back5write13differentiate ()
   from /home/losch/Documents/rust-ml/rustc2/build/x86_64-unknown-linux-gnu/stage1/bin/../lib/librustc_driver-2de1a356481e0f08.so
EnzymeAD/Enzyme#7  0x00007ffff4586408 in _RINvNtNtCsaXwx0AdOzVa_17rustc_codegen_ssa4back5write17generate_lto_workNtCs8k9sJ7haxZX_18rustc_codegen_llvm18LlvmCodegenBackendEB19_ ()
   from /home/losch/Documents/rust-ml/rustc2/build/x86_64-unknown-linux-gnu/stage1/bin/../lib/librustc_driver-2de1a356481e0f08.so
EnzymeAD/Enzyme#8  0x00007ffff4663d64 in _RINvNtNtCsfR9V8ySqyK8_3std10sys_common9backtrace28___rust_begin_short_backtraceNCINvXs0_Cs8k9sJ7haxZX_18rustc_codegen_llvmNtB1o_18LlvmCodegenBackendNtNtNtCsaXwx0AdOzVa_17rustc_codegen_ssa6traits7backend19ExtraBackendMethods12spawn_threadNCINvNtNtB2s_4back5write20start_executing_workB1W_Es2_0INtNtCsfYALMPu6VcR_4core6result6ResultNtB3S_15CompiledModulesuEE0B4G_EB1o_ ()
   from /home/losch/Documents/rust-ml/rustc2/build/x86_64-unknown-linux-gnu/stage1/bin/../lib/librustc_driver-2de1a356481e0f08.so
EnzymeAD/Enzyme#9  0x00007ffff4668997 in _RNSNvYNCINvMNtCsfR9V8ySqyK8_3std6threadNtBa_7Builder16spawn_unchecked_NCINvXs0_Cs8k9sJ7haxZX_18rustc_codegen_llvmNtB1f_18LlvmCodegenBackendNtNtNtCsaXwx0AdOzVa_17rustc_codegen_ssa6traits7backend19ExtraBackendMethods12spawn_threadNCINvNtNtB2j_4back5write20start_executing_workB1N_Es2_0INtNtCsfYALMPu6VcR_4core6result6ResultNtB3J_15CompiledModulesuEE0B4x_Es_0INtNtNtB4C_3ops8function6FnOnceuE9call_once6vtableB1f_ ()
   from /home/losch/Documents/rust-ml/rustc2/build/x86_64-unknown-linux-gnu/stage1/bin/../lib/librustc_driver-2de1a356481e0f08.so
EnzymeAD/Enzyme#10 0x00007ffff3b85fc5 in std::sys::unix::thread::Thread::new::thread_start ()
   from /home/losch/Documents/rust-ml/rustc2/build/x86_64-unknown-linux-gnu/stage1/bin/../lib/libstd-bce0a345943e55b3.so
EnzymeAD/Enzyme#11 0x00007fffe4568609 in start_thread (arg=<optimized out>) at pthread_create.c:477
EnzymeAD/Enzyme#12 0x00007ffff39bb133 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95