# cython: infer_types=True, cdivision=True, boundscheck=False cimport numpy as np from libc.math cimport exp from libc.string cimport memset, memcpy from libc.stdlib cimport calloc, free, realloc from thinc.backends.linalg cimport Vec, VecVec import numpy import numpy.random from thinc.api import Model, CupyOps, NumpyOps, get_ops from .. import util from ..errors import Errors from ..typedefs cimport weight_t, class_t, hash_t from ..pipeline._parser_internals.stateclass cimport StateClass cdef WeightsC get_c_weights(model) except *: cdef WeightsC output cdef precompute_hiddens state2vec = model.state2vec output.feat_weights = state2vec.get_feat_weights() output.feat_bias = state2vec.bias.data cdef np.ndarray vec2scores_W cdef np.ndarray vec2scores_b if model.vec2scores is None: output.hidden_weights = NULL output.hidden_bias = NULL else: vec2scores_W = model.vec2scores.get_param("W") vec2scores_b = model.vec2scores.get_param("b") output.hidden_weights = vec2scores_W.data output.hidden_bias = vec2scores_b.data cdef np.ndarray class_mask = model._class_mask output.seen_classes = class_mask.data return output cdef SizesC get_c_sizes(model, int batch_size) except *: cdef SizesC output output.states = batch_size if model.vec2scores is None: output.classes = model.state2vec.get_dim("nO") else: output.classes = model.vec2scores.get_dim("nO") output.hiddens = model.state2vec.get_dim("nO") output.pieces = model.state2vec.get_dim("nP") output.feats = model.state2vec.get_dim("nF") output.embed_width = model.tokvecs.shape[1] return output cdef ActivationsC alloc_activations(SizesC n) nogil: cdef ActivationsC A memset(&A, 0, sizeof(A)) resize_activations(&A, n) return A cdef void free_activations(const ActivationsC* A) nogil: free(A.token_ids) free(A.scores) free(A.unmaxed) free(A.hiddens) free(A.is_valid) cdef void resize_activations(ActivationsC* A, SizesC n) nogil: if n.states <= A._max_size: A._curr_size = n.states return if A._max_size == 0: A.token_ids = calloc(n.states * n.feats, sizeof(A.token_ids[0])) A.scores = calloc(n.states * n.classes, sizeof(A.scores[0])) A.unmaxed = calloc(n.states * n.hiddens * n.pieces, sizeof(A.unmaxed[0])) A.hiddens = calloc(n.states * n.hiddens, sizeof(A.hiddens[0])) A.is_valid = calloc(n.states * n.classes, sizeof(A.is_valid[0])) A._max_size = n.states else: A.token_ids = realloc(A.token_ids, n.states * n.feats * sizeof(A.token_ids[0])) A.scores = realloc(A.scores, n.states * n.classes * sizeof(A.scores[0])) A.unmaxed = realloc(A.unmaxed, n.states * n.hiddens * n.pieces * sizeof(A.unmaxed[0])) A.hiddens = realloc(A.hiddens, n.states * n.hiddens * sizeof(A.hiddens[0])) A.is_valid = realloc(A.is_valid, n.states * n.classes * sizeof(A.is_valid[0])) A._max_size = n.states A._curr_size = n.states cdef void predict_states(CBlas cblas, ActivationsC* A, StateC** states, const WeightsC* W, SizesC n) nogil: cdef double one = 1.0 resize_activations(A, n) for i in range(n.states): states[i].set_context_tokens(&A.token_ids[i*n.feats], n.feats) memset(A.unmaxed, 0, n.states * n.hiddens * n.pieces * sizeof(float)) memset(A.hiddens, 0, n.states * n.hiddens * sizeof(float)) sum_state_features(cblas, A.unmaxed, W.feat_weights, A.token_ids, n.states, n.feats, n.hiddens * n.pieces) for i in range(n.states): VecVec.add_i(&A.unmaxed[i*n.hiddens*n.pieces], W.feat_bias, 1., n.hiddens * n.pieces) for j in range(n.hiddens): index = i * n.hiddens * n.pieces + j * n.pieces which = Vec.arg_max(&A.unmaxed[index], n.pieces) A.hiddens[i*n.hiddens + j] = A.unmaxed[index + which] memset(A.scores, 0, n.states * n.classes * sizeof(float)) if W.hidden_weights == NULL: memcpy(A.scores, A.hiddens, n.states * n.classes * sizeof(float)) else: # Compute hidden-to-output cblas.sgemm()(False, True, n.states, n.classes, n.hiddens, 1.0, A.hiddens, n.hiddens, W.hidden_weights, n.hiddens, 0.0, A.scores, n.classes) # Add bias for i in range(n.states): VecVec.add_i(&A.scores[i*n.classes], W.hidden_bias, 1., n.classes) # Set unseen classes to minimum value i = 0 min_ = A.scores[0] for i in range(1, n.states * n.classes): if A.scores[i] < min_: min_ = A.scores[i] for i in range(n.states): for j in range(n.classes): if not W.seen_classes[j]: A.scores[i*n.classes+j] = min_ cdef void sum_state_features(CBlas cblas, float* output, const float* cached, const int* token_ids, int B, int F, int O) nogil: cdef int idx, b, f, i cdef const float* feature padding = cached cached += F * O cdef int id_stride = F*O cdef float one = 1. for b in range(B): for f in range(F): if token_ids[f] < 0: feature = &padding[f*O] else: idx = token_ids[f] * id_stride + f*O feature = &cached[idx] cblas.saxpy()(O, one, feature, 1, &output[b*O], 1) token_ids += F cdef void cpu_log_loss(float* d_scores, const float* costs, const int* is_valid, const float* scores, int O) nogil: """Do multi-label log loss""" cdef double max_, gmax, Z, gZ best = arg_max_if_gold(scores, costs, is_valid, O) guess = Vec.arg_max(scores, O) if best == -1 or guess == -1: # These shouldn't happen, but if they do, we want to make sure we don't # cause an OOB access. return Z = 1e-10 gZ = 1e-10 max_ = scores[guess] gmax = scores[best] for i in range(O): Z += exp(scores[i] - max_) if costs[i] <= costs[best]: gZ += exp(scores[i] - gmax) for i in range(O): if costs[i] <= costs[best]: d_scores[i] = (exp(scores[i]-max_) / Z) - (exp(scores[i]-gmax)/gZ) else: d_scores[i] = exp(scores[i]-max_) / Z cdef int arg_max_if_gold(const weight_t* scores, const weight_t* costs, const int* is_valid, int n) nogil: # Find minimum cost cdef float cost = 1 for i in range(n): if is_valid[i] and costs[i] < cost: cost = costs[i] # Now find best-scoring with that cost cdef int best = -1 for i in range(n): if costs[i] <= cost and is_valid[i]: if best == -1 or scores[i] > scores[best]: best = i return best cdef int arg_max_if_valid(const weight_t* scores, const int* is_valid, int n) nogil: cdef int best = -1 for i in range(n): if is_valid[i] >= 1: if best == -1 or scores[i] > scores[best]: best = i return best class ParserStepModel(Model): def __init__(self, docs, layers, *, has_upper, unseen_classes=None, train=True, dropout=0.1): Model.__init__(self, name="parser_step_model", forward=step_forward) self.attrs["has_upper"] = has_upper self.attrs["dropout_rate"] = dropout self.tokvecs, self.bp_tokvecs = layers[0](docs, is_train=train) if layers[1].get_dim("nP") >= 2: activation = "maxout" elif has_upper: activation = None else: activation = "relu" self.state2vec = precompute_hiddens(len(docs), self.tokvecs, layers[1], activation=activation, train=train) if has_upper: self.vec2scores = layers[-1] else: self.vec2scores = None self.cuda_stream = util.get_cuda_stream(non_blocking=True) self.backprops = [] self._class_mask = numpy.zeros((self.nO,), dtype='f') self._class_mask.fill(1) if unseen_classes is not None: for class_ in unseen_classes: self._class_mask[class_] = 0. def clear_memory(self): del self.tokvecs del self.bp_tokvecs del self.state2vec del self.backprops del self._class_mask @property def nO(self): if self.attrs["has_upper"]: return self.vec2scores.get_dim("nO") else: return self.state2vec.get_dim("nO") def class_is_unseen(self, class_): return self._class_mask[class_] def mark_class_unseen(self, class_): self._class_mask[class_] = 0 def mark_class_seen(self, class_): self._class_mask[class_] = 1 def get_token_ids(self, states): cdef StateClass state states = [state for state in states if not state.is_final()] cdef np.ndarray ids = numpy.zeros((len(states), self.state2vec.nF), dtype='i', order='C') ids.fill(-1) c_ids = ids.data for state in states: state.c.set_context_tokens(c_ids, ids.shape[1]) c_ids += ids.shape[1] return ids def backprop_step(self, token_ids, d_vector, get_d_tokvecs): if isinstance(self.state2vec.ops, CupyOps) \ and not isinstance(token_ids, self.state2vec.ops.xp.ndarray): # Move token_ids and d_vector to GPU, asynchronously self.backprops.append(( util.get_async(self.cuda_stream, token_ids), util.get_async(self.cuda_stream, d_vector), get_d_tokvecs )) else: self.backprops.append((token_ids, d_vector, get_d_tokvecs)) def finish_steps(self, golds): # Add a padding vector to the d_tokvecs gradient, so that missing # values don't affect the real gradient. d_tokvecs = self.ops.alloc((self.tokvecs.shape[0]+1, self.tokvecs.shape[1])) # Tells CUDA to block, so our async copies complete. if self.cuda_stream is not None: self.cuda_stream.synchronize() for ids, d_vector, bp_vector in self.backprops: d_state_features = bp_vector((d_vector, ids)) ids = ids.flatten() d_state_features = d_state_features.reshape( (ids.size, d_state_features.shape[2])) self.ops.scatter_add(d_tokvecs, ids, d_state_features) # Padded -- see update() self.bp_tokvecs(d_tokvecs[:-1]) return d_tokvecs NUMPY_OPS = NumpyOps() def step_forward(model: ParserStepModel, states, is_train): token_ids = model.get_token_ids(states) vector, get_d_tokvecs = model.state2vec(token_ids, is_train) mask = None if model.attrs["has_upper"]: dropout_rate = model.attrs["dropout_rate"] if is_train and dropout_rate > 0: mask = NUMPY_OPS.get_dropout_mask(vector.shape, 0.1) vector *= mask scores, get_d_vector = model.vec2scores(vector, is_train) else: scores = NumpyOps().asarray(vector) get_d_vector = lambda d_scores: d_scores # If the class is unseen, make sure its score is minimum scores[:, model._class_mask == 0] = numpy.nanmin(scores) def backprop_parser_step(d_scores): # Zero vectors for unseen classes d_scores *= model._class_mask d_vector = get_d_vector(d_scores) if mask is not None: d_vector *= mask model.backprop_step(token_ids, d_vector, get_d_tokvecs) return None return scores, backprop_parser_step cdef class precompute_hiddens: """Allow a model to be "primed" by pre-computing input features in bulk. This is used for the parser, where we want to take a batch of documents, and compute vectors for each (token, position) pair. These vectors can then be reused, especially for beam-search. Let's say we're using 12 features for each state, e.g. word at start of buffer, three words on stack, their children, etc. In the normal arc-eager system, a document of length N is processed in 2*N states. This means we'll create 2*N*12 feature vectors --- but if we pre-compute, we only need N*12 vector computations. The saving for beam-search is much better: if we have a beam of k, we'll normally make 2*N*12*K computations -- so we can save the factor k. This also gives a nice CPU/GPU division: we can do all our hard maths up front, packed into large multiplications, and do the hard-to-program parsing on the CPU. """ cdef readonly int nF, nO, nP cdef bint _is_synchronized cdef public object ops cdef public object numpy_ops cdef np.ndarray _features cdef np.ndarray _cached cdef np.ndarray bias cdef object _cuda_stream cdef object _bp_hiddens cdef object activation def __init__(self, batch_size, tokvecs, lower_model, cuda_stream=None, activation="maxout", train=False): gpu_cached, bp_features = lower_model(tokvecs, train) cdef np.ndarray cached if not isinstance(gpu_cached, numpy.ndarray): # Note the passing of cuda_stream here: it lets # cupy make the copy asynchronously. # We then have to block before first use. cached = gpu_cached.get(stream=cuda_stream) else: cached = gpu_cached if not isinstance(lower_model.get_param("b"), numpy.ndarray): self.bias = lower_model.get_param("b").get(stream=cuda_stream) else: self.bias = lower_model.get_param("b") self.nF = cached.shape[1] if lower_model.has_dim("nP"): self.nP = lower_model.get_dim("nP") else: self.nP = 1 self.nO = cached.shape[2] self.ops = lower_model.ops self.numpy_ops = NumpyOps() assert activation in (None, "relu", "maxout") self.activation = activation self._is_synchronized = False self._cuda_stream = cuda_stream self._cached = cached self._bp_hiddens = bp_features cdef const float* get_feat_weights(self) except NULL: if not self._is_synchronized and self._cuda_stream is not None: self._cuda_stream.synchronize() self._is_synchronized = True return self._cached.data def has_dim(self, name): if name == "nF": return self.nF if self.nF is not None else True elif name == "nP": return self.nP if self.nP is not None else True elif name == "nO": return self.nO if self.nO is not None else True else: return False def get_dim(self, name): if name == "nF": return self.nF elif name == "nP": return self.nP elif name == "nO": return self.nO else: raise ValueError(Errors.E1033.format(name=name)) def set_dim(self, name, value): if name == "nF": self.nF = value elif name == "nP": self.nP = value elif name == "nO": self.nO = value else: raise ValueError(Errors.E1033.format(name=name)) def __call__(self, X, bint is_train): if is_train: return self.begin_update(X) else: return self.predict(X), lambda X: X def predict(self, X): return self.begin_update(X)[0] def begin_update(self, token_ids): cdef np.ndarray state_vector = numpy.zeros( (token_ids.shape[0], self.nO, self.nP), dtype='f') # This is tricky, but (assuming GPU available); # - Input to forward on CPU # - Output from forward on CPU # - Input to backward on GPU! # - Output from backward on GPU bp_hiddens = self._bp_hiddens cdef CBlas cblas if isinstance(self.ops, CupyOps): cblas = get_ops("cpu").cblas() else: cblas = self.ops.cblas() feat_weights = self.get_feat_weights() cdef int[:, ::1] ids = token_ids sum_state_features(cblas, state_vector.data, feat_weights, &ids[0,0], token_ids.shape[0], self.nF, self.nO*self.nP) state_vector += self.bias state_vector, bp_nonlinearity = self._nonlinearity(state_vector) def backward(d_state_vector_ids): d_state_vector, token_ids = d_state_vector_ids d_state_vector = bp_nonlinearity(d_state_vector) d_tokens = bp_hiddens((d_state_vector, token_ids)) return d_tokens return state_vector, backward def _nonlinearity(self, state_vector): if self.activation == "maxout": return self._maxout_nonlinearity(state_vector) else: return self._relu_nonlinearity(state_vector) def _maxout_nonlinearity(self, state_vector): state_vector, mask = self.numpy_ops.maxout(state_vector) # We're outputting to CPU, but we need this variable on GPU for the # backward pass. mask = self.ops.asarray(mask) def backprop_maxout(d_best): return self.ops.backprop_maxout(d_best, mask, self.nP) return state_vector, backprop_maxout def _relu_nonlinearity(self, state_vector): state_vector = state_vector.reshape((state_vector.shape[0], -1)) mask = state_vector >= 0. state_vector *= mask # We're outputting to CPU, but we need this variable on GPU for the # backward pass. mask = self.ops.asarray(mask) def backprop_relu(d_best): d_best *= mask return d_best.reshape((d_best.shape + (1,))) return state_vector, backprop_relu