[dynamo] Graph break properly on dict key error

[williamwen42]

Found as a part of debugging #93624

Code:

import torch

d = {}

def fn(x):
    try:
        y = d[0]
    except KeyError:
        y = 1
    return x + y

opt_fn = torch.compile(fn, backend="eager")
opt_fn(torch.randn(3, 3))

Error:

Traceback (most recent call last):
  File "/data/users/williamwen/pytorch2/playground3.py", line 13, in <module>
    opt_fn(torch.randn(3, 3))
  File "/data/users/williamwen/pytorch2/torch/_dynamo/eval_frame.py", line 420, in _fn
    return fn(*args, **kwargs)
  File "/data/users/williamwen/pytorch2/torch/_dynamo/convert_frame.py", line 981, in catch_errors
    return callback(frame, cache_entry, hooks, frame_state, skip=1)
  File "/data/users/williamwen/pytorch2/torch/_dynamo/convert_frame.py", line 822, in _convert_frame
    result = inner_convert(
  File "/data/users/williamwen/pytorch2/torch/_dynamo/convert_frame.py", line 410, in _convert_frame_assert
    return _compile(
  File "/data/users/williamwen/pytorch2/torch/_utils_internal.py", line 70, in wrapper_function
    return function(*args, **kwargs)
  File "/data/users/williamwen/py310-env/lib/python3.10/contextlib.py", line 79, in inner
    return func(*args, **kwds)
  File "/data/users/williamwen/pytorch2/torch/_dynamo/convert_frame.py", line 732, in _compile
    raise InternalTorchDynamoError(str(e)).with_traceback(
  File "/data/users/williamwen/pytorch2/torch/_dynamo/convert_frame.py", line 703, in _compile
    guarded_code = compile_inner(code, one_graph, hooks, transform)
  File "/data/users/williamwen/pytorch2/torch/_dynamo/utils.py", line 273, in time_wrapper
    r = func(*args, **kwargs)
  File "/data/users/williamwen/pytorch2/torch/_dynamo/convert_frame.py", line 570, in compile_inner
    out_code = transform_code_object(code, transform)
  File "/data/users/williamwen/pytorch2/torch/_dynamo/bytecode_transformation.py", line 1167, in transform_code_object
    transformations(instructions, code_options)
  File "/data/users/williamwen/pytorch2/torch/_dynamo/convert_frame.py", line 172, in _fn
    return fn(*args, **kwargs)
  File "/data/users/williamwen/pytorch2/torch/_dynamo/convert_frame.py", line 517, in transform
    tracer.run()
  File "/data/users/williamwen/pytorch2/torch/_dynamo/symbolic_convert.py", line 2234, in run
    super().run()
  File "/data/users/williamwen/pytorch2/torch/_dynamo/symbolic_convert.py", line 884, in run
    while self.step():
  File "/data/users/williamwen/pytorch2/torch/_dynamo/symbolic_convert.py", line 799, in step
    self.dispatch_table[inst.opcode](self, inst)
  File "/data/users/williamwen/pytorch2/torch/_dynamo/symbolic_convert.py", line 494, in wrapper
    return inner_fn(self, inst)
  File "/data/users/williamwen/pytorch2/torch/_dynamo/symbolic_convert.py", line 231, in impl
    self.push(fn_var.call_function(self, self.popn(nargs), {}))
  File "/data/users/williamwen/pytorch2/torch/_dynamo/variables/builtin.py", line 946, in call_function
    return handler(tx, args, kwargs)
  File "/data/users/williamwen/pytorch2/torch/_dynamo/variables/builtin.py", line 830, in builtin_dipatch
    rv = fn(tx, args, kwargs)
  File "/data/users/williamwen/pytorch2/torch/_dynamo/variables/builtin.py", line 750, in call_self_handler
    result = self_handler(tx, *args, **kwargs)
  File "/data/users/williamwen/pytorch2/torch/_dynamo/variables/builtin.py", line 1346, in call_getitem
    return args[0].call_method(tx, "__getitem__", args[1:], kwargs)
  File "/data/users/williamwen/pytorch2/torch/_dynamo/variables/dicts.py", line 224, in call_method
    return self.getitem_const(args[0])
  File "/data/users/williamwen/pytorch2/torch/_dynamo/variables/dicts.py", line 200, in getitem_const
    raise KeyError(arg.value)
torch._dynamo.exc.InternalTorchDynamoError: 0

from user code:
   File "/data/users/williamwen/pytorch2/playground3.py", line 7, in fn
    y = d[0]

We should graph break cleanly, not error out.

cc @ezyang @msaroufim @bdhirsh @anijain2305 @chauhang @voznesenskym @penguinwu @EikanWang @jgong5 @Guobing-Chen @XiaobingSuper @zhuhaozhe @blzheng @wenzhe-nrv @jiayisunx @chenyang78 @kadeng