Error occured trying int8 quantization

Hi, I’m trying to add int8 quantization to my autotvm tuning. for that, I simply copied those lines from @vinx13’s benchmark while extracting the tasks:

with relay.quantize.qconfig(store_lowbit_output=False):
    model["main"]= relay.quantize.quantize(model["main"], params=params)
tasks = autotvm.task.extract_from_program(model["main"], target=target,
                                      params=params, ops=(relay.op.nn.conv2d))

But this gives me an error like:

Traceback (most recent call last):

  File "./", line 52, in <module>
    tasks = extract_tasks(model, params, target, quantize=True)

  File "/home/can/Dev/tvm_wd/", line 51, in extract_tasks
    model["main"]= relay.quantize.quantize(model["main"], params=params)

  File "/home/can/Dev/tvm/python/tvm/relay/quantize/", line 339, in quantize
    mod = prerequisite_optimize(mod, params)

  File "/home/can/Dev/tvm/python/tvm/relay/quantize/", line 310, in prerequisite_optimize
    mod['main'] = _bind_params(mod['main'], params)

TypeError: 'Function' object is not subscriptable

Then I remove the ['main'] parts after mod and modified it as mod= relay.quantize.quantize(mod, params=params)

this time I get another error like:

Exception in thread Thread-1:
Traceback (most recent call last):
  File "/usr/lib/python3.6/", line 916, in _bootstrap_inner
  File "/usr/lib/python3.6/", line 864, in run
    self._target(*self._args, **self._kwargs)
  File "/home/can/Dev/tvm/python/tvm/autotvm/task/", line 56, in _lower
    opt_mod, _ = relay.optimize(mod, target, params)
  File "/home/can/Dev/tvm/python/tvm/relay/", line 303, in optimize
    mod, params = bld_mod.optimize(mod, target, params)
  File "/home/can/Dev/tvm/python/tvm/relay/", line 157, in optimize
    mod = self._optimize(mod, target)
  File "tvm/_ffi/_cython/./packed_func.pxi", line 315, in tvm._ffi._cy3.core.PackedFuncBase.__call__
  File "tvm/_ffi/_cython/./packed_func.pxi", line 250, in tvm._ffi._cy3.core.FuncCall
  File "tvm/_ffi/_cython/./packed_func.pxi", line 239, in tvm._ffi._cy3.core.FuncCall3
  File "tvm/_ffi/_cython/./base.pxi", line 160, in tvm._ffi._cy3.core.CALL
TypeError: Traceback (most recent call last):
  [bt] (8) /home/can/Dev/tvm/build/ const&, tvm::Array<tvm::runtime::ObjectRef, void> const&)+0x5fc) [0x7f3b3700354c]
  [bt] (7) /home/can/Dev/tvm/build/ const&)+0x32) [0x7f3b36fd0a62]
  [bt] (6) /home/can/Dev/tvm/build/ const&)+0x685) [0x7f3b36fcff45]
  [bt] (5) /home/can/Dev/tvm/build/ const&)+0x574) [0x7f3b36fcc984]
  [bt] (4) /home/can/Dev/tvm/build/<tvm::Array<tvm::te::Tensor, void> >::VisitExpr(tvm::RelayExpr const&)+0xb3) [0x7f3b36fd2ff3]
  [bt] (3) /home/can/Dev/tvm/build/<tvm::Array<tvm::te::Tensor, void> (tvm::RelayExpr const&)>::VisitExpr(tvm::RelayExpr const&)+0x91) [0x7f3b36fd13d1]
  [bt] (2) /home/can/Dev/tvm/build/<tvm::Array<tvm::te::Tensor, void> (tvm::RelayExpr const&)>::InitVTable()::{lambda(tvm::runtime::ObjectRef const&, tvm::relay::ExprFunctor<tvm::Array<tvm::te::Tensor, void> (tvm::RelayExpr const&)>*)#6}::_FUN(tvm::runtime::ObjectRef const&, tvm::relay::ExprFunctor<tvm::Array<tvm::te::Tensor, void> (tvm::RelayExpr const&)>*)+0x27) [0x7f3b36fc5137]
  [bt] (1) /home/can/Dev/tvm/build/ const*)+0x6b3) [0x7f3b36fcb5b3]
  [bt] (0) /home/can/Dev/tvm/build/ [0x7f3b37112f1b]
  File "tvm/_ffi/_cython/./packed_func.pxi", line 55, in tvm._ffi._cy3.core.tvm_callback
  File "/home/can/Dev/tvm/python/tvm/relay/backend/", line 244, in lower_call
    if env.wanted_relay_ops is not None and op not in env.wanted_relay_ops:
TypeError: argument of type 'function' is not iterable

I can’t figure out what happens. If you can look here, I would be glad.

I believe this is an issue with the transition of module to module style pass api. The error indicated that mod['main'] is invalid, I expect mod here to be tvm.runtime.Module, if not maybe you need to check the input, for example try model["main"]= relay.quantize.quantize(model, params=params)

Hi @vinx13, thanks for your comment. I get the mod variable using relay.frontend.from_. Its type is ir.module.IRModule. Is there anything wrong here?

Btw, mod['main'] = relay.quantize.quantize(mod, params=params) throws AssertionError. Actually, mod = relay.quantize.quantize(mod, params=params) doesn’t give any error, but this time autotvm.task.extract_from_program says function is not iterable. If I put ['main'] each side, then it gives ‘Function’ object is not subscriptable

relay.frontend.from_ should return a module

I found that the problem looks disappear when I remove this option ops=(relay.op.nn.conv2d, relay.op.nn.dense) in the method autotvm.task.extract_from_program, which you used in your tutorial. Maybe the usage of this option has been changed?

Yes it has changed, if you don’t specify ops, by default it will extract all tunable ops now

if there any way to fix it, even i have same errors as

TypeError: ‘Function’ object is not subscriptable

@OriAlpha, it’s solved when I did:

mod = relay.quantize.quantize(mod, params=params)

and delete:

ops=(relay.op.nn.conv2d, relay.op.nn.dense) in the method autotvm.task.extract_from_program

perfect its working now.