gemma.cpp/gemma/gemma.cc

919 lines
37 KiB
C++

// Copyright 2024 Google LLC
// SPDX-License-Identifier: Apache-2.0
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Lightweight C++ implementation of the gemma model.
// Compiles this file for multiple architectures via "foreach_target.h", to
// which we pass the filename via macro 'argument'.
#undef HWY_TARGET_INCLUDE
#define HWY_TARGET_INCLUDE "gemma/gemma.cc" // NOLINT
#include "hwy/foreach_target.h" // IWYU pragma: keep
// Must come after foreach_target.h to avoid redefinition errors.
#include "gemma/ops.h"
#include "hwy/contrib/matvec/matvec-inl.h"
#include "hwy/highway.h"
// Non-SIMD includes and types. Note that HWY_ONCE is only true on the last
// compile pass, whereas we want this defined in the first.
#ifndef GEMMA_ONCE
#define GEMMA_ONCE
#include <math.h> // sqrtf
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <algorithm>
#include <array>
#include <cmath>
#include <memory>
#include <string>
#include <utility>
#include <vector>
#include "compression/io.h" // Path
#include "gemma/common.h"
#include "gemma/configs.h"
#include "gemma/gemma.h"
#include "gemma/weights.h"
#include "hwy/aligned_allocator.h"
#include "hwy/base.h"
#include "hwy/contrib/thread_pool/thread_pool.h"
#include "hwy/profiler.h"
#include "hwy/timer.h"
// copybara:import_next_line:sentencepiece
#include "src/sentencepiece_processor.h"
namespace gcpp {
// Set this to true to debug tokenizer tokens.
constexpr bool kShowTokenization = false;
// Must be aligned.
template <class TConfig, size_t kBatchSize>
struct Activations {
using LayerConfig = LayerF<TConfig>;
static constexpr size_t kModelDim = TConfig::kModelDim;
static constexpr size_t kQKVDim = TConfig::kQKVDim;
static constexpr size_t kHeads = TConfig::kHeads;
static constexpr size_t kKVHeads = TConfig::kKVHeads;
static constexpr size_t kCacheLayerSize = kKVHeads * kQKVDim * 2;
static constexpr size_t kCachePosSize =
TConfig::kGemmaLayers * kCacheLayerSize;
static constexpr size_t kQDim = kHeads == kKVHeads ? kQKVDim * 3 : kQKVDim;
std::array<float, kBatchSize * kModelDim> x; // input
std::array<float, kBatchSize * kModelDim> pre_att_rms_out;
std::array<float, kBatchSize * kHeads * kQDim> q; // query vector
std::array<float, kBatchSize * kHeads * TConfig::kSeqLen>
att; // attention vector
std::array<float, kBatchSize * kHeads * kQKVDim> att_out; // attention output
std::array<float, kHeads * kBatchSize * kModelDim>
att_post1; // attention output after linear transformation, per head
std::array<float, kBatchSize * kModelDim>
att_post2; // accumulation of attention outputs over heads
std::array<hwy::bfloat16_t, kBatchSize * kModelDim> bf_pre_ffw_rms_out;
std::array<float, kBatchSize * TConfig::kFFHiddenDim * 2> ffw_hidden;
// bf_ version can't be used until GeluMulToBF16 issue in FFW() is resolved.
// std::array<hwy::bfloat16_t, kBatchSize * 2 * TConfig::kFFHiddenDim>
// bf_ffw_hidden;
std::array<float, kBatchSize * kModelDim> ffw_out;
std::array<float, kBatchSize * TConfig::kVocabSize> logits;
// For bf16/f32 vectors * bf16 matrix: faster to unpack once beforehand, into
// per-thread storage.
std::array<float, kModelDim * kMaxThreads> even_odd;
// Griffin layer internal activations
static constexpr size_t kGriffinDim =
TConfig::kGriffinLayers > 0 ? kModelDim : 0;
std::array<float, kBatchSize * kGriffinDim> griffin_x;
std::array<float, kBatchSize * kGriffinDim> griffin_y;
std::array<float, kBatchSize * kGriffinDim> griffin_gate_x;
std::array<float, kBatchSize * kGriffinDim> griffin_multiplier;
};
namespace {
template <class TConfig>
struct CreateKVCache {
KVCache operator()() const {
KVCache kv_cache = {};
const size_t size_cache_pos =
TConfig::kGemmaLayers * TConfig::kKVHeads * TConfig::kQKVDim;
if (size_cache_pos != 0) {
const size_t seq_len = TConfig::kSeqLen + kPrefillBatchSize;
kv_cache.kv_cache =
hwy::AllocateAligned<float>(seq_len * size_cache_pos * 2);
}
if (TConfig::kGriffinLayers) {
constexpr size_t kConv1dWidth = TConfig::kConv1dWidth;
const size_t conv1d_cache_size =
TConfig::kGriffinLayers * (kConv1dWidth == 0 ? 0 : kConv1dWidth - 1) *
TConfig::kModelDim;
if (conv1d_cache_size != 0) {
kv_cache.conv1d_cache = hwy::AllocateAligned<float>(conv1d_cache_size);
hwy::ZeroBytes(kv_cache.conv1d_cache.get(),
conv1d_cache_size * sizeof(kv_cache.conv1d_cache[0]));
}
const size_t rglru_cache_size =
TConfig::kGriffinLayers * TConfig::kModelDim;
if (rglru_cache_size != 0) {
kv_cache.rglru_cache = hwy::AllocateAligned<float>(rglru_cache_size);
hwy::ZeroBytes(kv_cache.rglru_cache.get(),
rglru_cache_size * sizeof(kv_cache.rglru_cache[0]));
}
} // kGriffinLayers
return kv_cache;
}
};
} // namespace
KVCache KVCache::Create(Model model_type) {
// TWeight=float is a placeholder and unused because CreateKVCache does not
// use TConfig::Weight.
return CallForModel</*TWeight=*/float, CreateKVCache>(model_type);
}
class GemmaTokenizer::Impl {
public:
Impl() = default;
explicit Impl(const Path& tokenizer_path) {
PROFILER_ZONE("Startup.tokenizer");
spp_ = std::make_unique<sentencepiece::SentencePieceProcessor>();
if (!spp_->Load(tokenizer_path.path).ok()) {
HWY_ABORT("Failed to load the tokenizer file.");
}
}
bool Encode(const std::string& input,
std::vector<std::string>* pieces) const {
return spp_ && spp_->Encode(input, pieces).ok();
}
bool Encode(const std::string& input, std::vector<int>* pieces) const {
if constexpr (kShowTokenization) {
bool is_ok = spp_ && spp_->Encode(input, pieces).ok();
for (int i = 0; i < static_cast<int>(pieces->size()); i++) {
fprintf(stderr, "%3d: %d\n", i, (*pieces)[i]);
}
return is_ok;
} else {
return spp_ && spp_->Encode(input, pieces).ok();
}
}
// Given a sequence of ids, decodes it into a detokenized output.
bool Decode(const std::vector<int>& ids, std::string* detokenized) const {
return spp_ && spp_->Decode(ids, detokenized).ok();
}
private:
std::unique_ptr<sentencepiece::SentencePieceProcessor> spp_;
};
GemmaTokenizer::GemmaTokenizer(const Path& tokenizer_path) {
impl_ = std::make_unique<Impl>(tokenizer_path);
}
GemmaTokenizer::GemmaTokenizer() {
impl_ = std::make_unique<Impl>();
}
GemmaTokenizer::~GemmaTokenizer() = default;
GemmaTokenizer::GemmaTokenizer(GemmaTokenizer&& other) = default;
GemmaTokenizer& GemmaTokenizer::operator=(GemmaTokenizer&& other) = default;
bool GemmaTokenizer::Encode(const std::string& input,
std::vector<std::string>* pieces) const {
return impl_->Encode(input, pieces);
}
bool GemmaTokenizer::Encode(const std::string& input,
std::vector<int>* pieces) const {
return impl_->Encode(input, pieces);
}
// Given a sequence of ids, decodes it into a detokenized output.
bool GemmaTokenizer::Decode(const std::vector<int>& ids,
std::string* detokenized) const {
return impl_->Decode(ids, detokenized);
}
} // namespace gcpp
#endif // GEMMA_ONCE
// SIMD code, compiled once per target.
HWY_BEFORE_NAMESPACE();
namespace gcpp {
namespace HWY_NAMESPACE {
namespace {
template <size_t kBatchSize, typename LayerT, class TConfig>
HWY_NOINLINE void GriffinRecurrent(
size_t batch_start, size_t num_tokens, size_t layer,
Activations<TConfig, kBatchSize>& activations, const LayerT* layer_weights,
KVCache& kv_cache, hwy::ThreadPool& pool) {
PROFILER_ZONE("Gen.Griffin");
namespace hn = hwy::HWY_NAMESPACE;
using D = hn::ScalableTag<float>;
HWY_DASSERT(num_tokens <= kBatchSize);
static constexpr size_t kModelDim =
gcpp::Activations<TConfig, kBatchSize>::kModelDim;
static constexpr size_t kConv1dWidth = TConfig::kConv1dWidth;
static constexpr size_t kHeads = TConfig::kHeads;
// X / Y linear layers.
for (size_t batch_idx = 0; batch_idx < num_tokens; ++batch_idx) {
const size_t batch_offset = batch_idx * kModelDim;
float* HWY_RESTRICT y = activations.griffin_y.data() + batch_offset;
float* HWY_RESTRICT x = activations.griffin_x.data() + batch_offset;
TwoMatVecAdd<kModelDim, kModelDim>(
layer_weights->griffin.linear_x_w, layer_weights->griffin.linear_y_w, 0,
activations.pre_att_rms_out.data() + batch_offset,
/*add0=*/layer_weights->griffin.linear_x_biases.data(),
/*add1=*/layer_weights->griffin.linear_y_biases.data(), /*out0=*/x,
/*out1=*/y, pool);
Gelu(y, kModelDim);
}
// Conv1D.
for (size_t batch_idx = 0; batch_idx < num_tokens; ++batch_idx) {
const size_t batch_offset = batch_idx * kModelDim;
const size_t pos = batch_start + batch_idx;
float* HWY_RESTRICT x = activations.griffin_x.data() + batch_offset;
HWY_FULL(float) df;
HWY_DASSERT(kModelDim % Lanes(df) == 0);
const size_t layer_offset = layer * kModelDim * (kConv1dWidth - 1);
// cache[i] = input at time t-i.
float* HWY_RESTRICT cache[HWY_MAX(kConv1dWidth, 1)];
cache[0] = x;
for (size_t i = 1; i < kConv1dWidth; i++) {
cache[i] =
kv_cache.conv1d_cache.get() + layer_offset +
((pos + kConv1dWidth - 1 - i) % (kConv1dWidth - 1)) * kModelDim;
}
for (size_t i = 0; i < kModelDim; i += Lanes(df)) {
auto xv = hn::Load(df, x + i);
auto accum0 =
hn::Load(df, layer_weights->griffin.conv_biases.data() + i);
auto accum1 = hn::Zero(df);
static_assert(kConv1dWidth % 2 == 0, "Conv width must be even");
for (size_t l = 0; 2 * l < kConv1dWidth; l++) {
auto wv0 = hn::Load(df, layer_weights->griffin.conv_w.data() +
(kConv1dWidth - 1 - 2 * l) * kModelDim + i);
auto wv1 = hn::Load(df, layer_weights->griffin.conv_w.data() +
(kConv1dWidth - 2 - 2 * l) * kModelDim + i);
accum0 = hn::MulAdd(wv0, hn::Load(df, cache[l * 2] + i), accum0);
accum1 = hn::MulAdd(wv1, hn::Load(df, cache[l * 2 + 1] + i), accum1);
}
hn::Store(hn::Add(accum0, accum1), df, x + i);
hn::Store(xv, df, cache[HWY_MAX(kConv1dWidth, 1) - 1] + i);
}
}
// RGLRU
for (size_t batch_idx = 0; batch_idx < num_tokens; ++batch_idx) {
const size_t batch_offset = batch_idx * kModelDim;
const size_t pos = batch_start + batch_idx;
float* HWY_RESTRICT y = activations.griffin_y.data() + batch_offset;
float* HWY_RESTRICT x = activations.griffin_x.data() + batch_offset;
float* HWY_RESTRICT gate_x =
activations.griffin_gate_x.data() + batch_offset;
float* HWY_RESTRICT a =
activations.griffin_multiplier.data() + batch_offset;
float* HWY_RESTRICT rnn_state =
kv_cache.rglru_cache.get() + layer * kModelDim;
pool.Run(0, kHeads, [&](const uint64_t head, size_t /*thread*/) HWY_ATTR {
constexpr size_t kHeadDim = kModelDim / kHeads;
constexpr size_t kMatrixSize = kHeadDim * kHeadDim;
size_t head_offset = head * kHeadDim;
TwoOfsMatVecAddLoop<kHeadDim, kHeadDim>(
layer_weights->griffin.gate_w, kMatrixSize * head,
kMatrixSize * (kHeads + head), x + head_offset,
/*add0=*/layer_weights->griffin.gate_biases.data() + head_offset,
/*add1=*/layer_weights->griffin.gate_biases.data() + kModelDim +
head_offset,
/*out0=*/gate_x + head_offset, /*out1=*/a + head_offset);
Sigmoid(gate_x + head_offset, kHeadDim);
Sigmoid(a + head_offset, kHeadDim);
const auto fn_mul = [](D d, hn::Vec<D> x, hn::Vec<D> gate_x)
HWY_ATTR { return hn::Mul(x, gate_x); };
hn::Transform1(D(), a + head_offset, kHeadDim,
layer_weights->griffin.a.data() + head_offset, fn_mul);
hn::Transform1(D(), x + head_offset, kHeadDim, gate_x + head_offset,
fn_mul);
// RNN scan
HWY_FULL(float) df;
HWY_DASSERT(kHeadDim % Lanes(df) == 0);
for (size_t i = 0; i < kHeadDim; i += Lanes(df)) {
auto log_a = hn::Load(df, a + head_offset + i);
auto gated_x = hn::Load(df, x + head_offset + i);
auto rnn = hn::Load(df, rnn_state + head_offset + i);
auto a = hn::Exp(df, log_a);
auto x_multiplier = hn::Sqrt(hn::NegMulAdd(a, a, hn::Set(df, 1.0)));
if (pos == 0) {
x_multiplier = hn::Set(df, 1.0);
}
auto new_x = hn::MulAdd(x_multiplier, gated_x, hn::Mul(a, rnn));
hn::Store(new_x, df, rnn_state + head_offset + i);
// Join branches.
auto yv = hn::Load(df, y + head_offset + i);
auto pre_out = hn::Mul(yv, new_x);
hn::Store(pre_out, df, x + head_offset + i);
}
});
}
// Final linear layer.
for (size_t batch_idx = 0; batch_idx < num_tokens; ++batch_idx) {
const size_t batch_offset = batch_idx * kModelDim;
float* HWY_RESTRICT x = activations.griffin_x.data() + batch_offset;
float* out_ptr = activations.att_post2.data() + batch_idx * kModelDim;
MatVecAdd<kModelDim, kModelDim>(
layer_weights->griffin.linear_out_w, 0, x,
layer_weights->griffin.linear_out_biases.data(),
activations.even_odd.data(), out_ptr, pool);
}
}
template <size_t kBatchSize, typename LayerT, class TConfig>
HWY_NOINLINE void Attention(size_t batch_start, size_t num_tokens, size_t layer,
Activations<TConfig, kBatchSize>& activations,
const LayerT* layer_weights, KVCache& kv_cache,
hwy::ThreadPool& pool) {
PROFILER_ZONE("Gen.Attention");
HWY_DASSERT(num_tokens <= kBatchSize);
static constexpr size_t kQKVDim = gcpp::Activations<TConfig, 1>::kQKVDim;
static constexpr size_t kCachePosSize =
gcpp::Activations<TConfig, kBatchSize>::kCachePosSize;
static constexpr size_t kCacheLayerSize =
gcpp::Activations<TConfig, kBatchSize>::kCacheLayerSize;
static constexpr size_t kModelDim =
gcpp::Activations<TConfig, kBatchSize>::kModelDim;
static constexpr size_t kHeads = TConfig::kHeads;
static constexpr size_t kKVHeads = TConfig::kKVHeads;
static constexpr size_t kSeqLen = TConfig::kSeqLen;
static const float kQueryScale =
static_cast<float>(1.0 / sqrt(static_cast<double>(kQKVDim)));
auto Attn = [&](float* q, uint64_t head, size_t head_offset, size_t batch_idx,
size_t thread) HWY_ATTR {
const size_t pos = batch_start + batch_idx;
// Calculate scores
float* HWY_RESTRICT head_att = activations.att.data() +
head * kSeqLen +
batch_idx * kHeads * kSeqLen;
Rope(q, TConfig::kUseHalfRope ? kQKVDim / 2 : kQKVDim, pos);
MulByConst(kQueryScale, q, kQKVDim);
// Compute Q dot K scores
const size_t start_pos = pos - std::min(kSeqLen - 1, pos);
for (size_t pos2 = start_pos; pos2 <= pos; ++pos2) {
const size_t cache_pos = pos2 % (kSeqLen + kPrefillBatchSize);
const size_t kv_offset = cache_pos * kCachePosSize +
layer * kCacheLayerSize + head_offset;
const float* HWY_RESTRICT k2 = kv_cache.kv_cache.get() + kv_offset;
const float score = Dot(q, k2, kQKVDim);
head_att[pos2 % kSeqLen] = score;
}
Softmax(head_att, std::min(pos + 1, kSeqLen));
// Weighted summation
float* HWY_RESTRICT att_out = activations.att_out.data() + head * kQKVDim +
batch_idx * kHeads * kQKVDim;
hwy::ZeroBytes(att_out, kQKVDim * sizeof(*att_out));
for (size_t pos2 = start_pos; pos2 <= pos; ++pos2) {
const size_t cache_pos = pos2 % (kSeqLen + kPrefillBatchSize);
const size_t kv_offset = cache_pos * kCachePosSize +
layer * kCacheLayerSize + head_offset;
float* HWY_RESTRICT v2 = kv_cache.kv_cache.get() + kv_offset + kQKVDim;
MulByConstAndAdd(head_att[pos2 % kSeqLen], v2, att_out, kQKVDim);
}
};
for (size_t batch_idx = 0; batch_idx < num_tokens; ++batch_idx) {
const float* x = activations.pre_att_rms_out.data() + batch_idx * kModelDim;
// QKV projections:
if constexpr (kHeads == kKVHeads) {
// Multi-Head Attention calculates qkv using q as scratch space.
static_assert(TConfig::kInterleaveQKV);
float* HWY_RESTRICT qkv =
activations.q.data() + batch_idx * kHeads * kQKVDim * 3;
MatVec<kHeads * kQKVDim * 3, kModelDim>(layer_weights->qkv_einsum_w, 0, x,
activations.even_odd.data(), qkv,
pool);
} else {
const size_t pos = batch_start + batch_idx;
float* HWY_RESTRICT q =
activations.q.data() + batch_idx * kHeads * kQKVDim;
MatVec<kHeads * kQKVDim, kModelDim>(layer_weights->qkv_einsum_w, 0, x,
activations.even_odd.data(), q, pool);
const size_t cache_pos = pos % (kSeqLen + kPrefillBatchSize);
const size_t kv_offset =
cache_pos * kCachePosSize + layer * kCacheLayerSize;
float* HWY_RESTRICT kv = kv_cache.kv_cache.get() + kv_offset;
MatVec<kKVHeads * kQKVDim * 2, kModelDim>(
layer_weights->qkv_einsum_w, kHeads * kQKVDim * kModelDim, x,
activations.even_odd.data(), kv, pool);
}
}
// Positional encodings for k:
const size_t num_kv_tasks = kKVHeads * num_tokens;
pool.Run(0, num_kv_tasks, [&](const uint64_t task, size_t thread) HWY_ATTR {
const size_t head = task % kKVHeads;
const size_t batch_idx = task / kKVHeads;
const size_t pos = batch_start + batch_idx;
const size_t cache_pos = pos % (kSeqLen + kPrefillBatchSize);
const size_t kv_offset = cache_pos * kCachePosSize +
layer * kCacheLayerSize + head * kQKVDim * 2;
float* HWY_RESTRICT kv = kv_cache.kv_cache.get() + kv_offset;
if constexpr (kHeads == kKVHeads) {
// For MHA, copy kv into the KV cache from scratch space (see above).
const float* HWY_RESTRICT q =
activations.q.data() + (batch_idx * kHeads + head) * kQKVDim * 3;
memcpy(kv, q + kQKVDim, 2 * kQKVDim * sizeof(float));
}
Rope(kv, TConfig::kUseHalfRope ? kQKVDim / 2 : kQKVDim, pos);
});
static_assert((TConfig::kHeads % TConfig::kKVHeads) == 0,
"query heads must be a multiple of key-value heads");
static constexpr size_t kGroupHeads = TConfig::kHeads / TConfig::kKVHeads;
static constexpr size_t kQOffsetScale = (kHeads == kKVHeads) ? 3 : 1;
const size_t num_q_tasks = kHeads * num_tokens;
pool.Run(0, num_q_tasks, [&](const uint64_t task, size_t thread) HWY_ATTR {
const size_t head = task % kHeads;
const size_t batch_idx = task / kHeads;
const size_t head_offset = (head / kGroupHeads) * kQKVDim * 2;
float* HWY_RESTRICT q = activations.q.data() + (batch_idx * kHeads + head) *
kQKVDim * kQOffsetScale;
Attn(q, head, head_offset, batch_idx, thread);
});
for (size_t batch_idx = 0; batch_idx < num_tokens; ++batch_idx) {
// TODO(szabadka) Use a single MatVecAdd like in GriffinRecurrent() after
// rearranging the weights.
float* HWY_RESTRICT att_out =
activations.att_out.data() + batch_idx * kHeads * kQKVDim;
float* HWY_RESTRICT layer_out =
activations.att_post2.data() + batch_idx * kModelDim;
MatVecT</*kAdd=*/TConfig::kSoftmaxAttnOutputBiases, kModelDim, kQKVDim>(
layer_weights->attn_vec_einsum_w, 0, att_out,
layer_weights->attention_output_biases.data(),
activations.even_odd.data(), layer_out, pool);
for (size_t head = 1; head < kHeads; ++head) {
float* HWY_RESTRICT head_out =
activations.att_post1.data() + head * kBatchSize * kModelDim;
MatVec<kModelDim, kQKVDim>(
layer_weights->attn_vec_einsum_w, head * kModelDim * kQKVDim,
att_out + head * kQKVDim,
activations.even_odd.data(), head_out, pool);
AddFrom(head_out, layer_out, kModelDim);
}
}
}
template <size_t kBatchSize, typename LayerT, typename TConfig>
HWY_NOINLINE void FFW(Activations<TConfig, kBatchSize>& activations,
size_t num_tokens, const LayerT* layer_weights,
hwy::ThreadPool& pool) {
HWY_DASSERT(num_tokens <= kBatchSize);
static constexpr size_t kModelDim = TConfig::kModelDim;
static constexpr size_t kFFHiddenDim = TConfig::kFFHiddenDim;
float* HWY_RESTRICT even_odd = activations.even_odd.data();
for (size_t batch_idx = 0; batch_idx < num_tokens; ++batch_idx) {
const size_t hidden_offset = batch_idx * kFFHiddenDim * 2;
PROFILER_ZONE("Gen.FFW.GatedGELU");
const hwy::bfloat16_t* HWY_RESTRICT vec =
activations.bf_pre_ffw_rms_out.data() + batch_idx * kModelDim;
float* HWY_RESTRICT out = activations.ffw_hidden.data() + hidden_offset;
float* HWY_RESTRICT out_mul = out + kFFHiddenDim;
// Same matrix, first and second half of rows. Could fuse into one MatVec.
MatVecT</*kAdd=*/TConfig::kFFBiases, kFFHiddenDim, kModelDim>(
layer_weights->gating_einsum_w, kFFHiddenDim * kModelDim, vec,
TConfig::kFFBiases ?
layer_weights->ffw_gating_biases.data() + kFFHiddenDim : nullptr,
even_odd, out_mul, pool);
// Gate, will go through the nonlinearity.
MatVecT</*kAdd=*/TConfig::kFFBiases, kFFHiddenDim, kModelDim>(
layer_weights->gating_einsum_w, 0, vec,
layer_weights->ffw_gating_biases.data(), even_odd, out, pool);
namespace hn = hwy::HWY_NAMESPACE;
using DF = hn::ScalableTag<float>;
using VF = hn::Vec<DF>;
hn::Transform1(DF(), out, kFFHiddenDim, out_mul,
[](DF df, VF v, VF mul)
HWY_ATTR { return hn::Mul(mul, Gelu(df, v)); });
}
for (size_t batch_idx = 0; batch_idx < num_tokens; ++batch_idx) {
PROFILER_ZONE("Gen.FFW\\GatedGELU");
const size_t hidden_offset = batch_idx * kFFHiddenDim * 2;
MatVecT</*kAdd=*/TConfig::kFFBiases, kModelDim, kFFHiddenDim>(
layer_weights->linear_w, 0,
activations.ffw_hidden.data() + hidden_offset,
layer_weights->ffw_output_biases.data(), even_odd,
activations.ffw_out.data() + batch_idx * kModelDim, pool);
}
}
template <size_t kBatchSize, typename WeightArrayT, typename TConfig>
HWY_NOINLINE void Prefill(const int* tokens, size_t num_tokens, size_t pos,
const WeightArrayT& weights,
Activations<TConfig, kBatchSize>& activations,
KVCache& kv_cache, hwy::ThreadPool& pool) {
PROFILER_ZONE("Gen.Prefill\\Att\\FFW");
static constexpr size_t kModelDim = TConfig::kModelDim;
GEMMA_CONSTEXPR_EMBSCALING const float kEmbScaling =
EmbeddingScaling<TConfig>();
pool.Run(
0, num_tokens, [&](const uint64_t token_idx, size_t /*thread*/) HWY_ATTR {
const int token = tokens[token_idx];
HWY_ASSERT(token >= 0);
HWY_ASSERT(token < TConfig::kVocabSize);
Decompress(weights.embedder_input_embedding, token * kModelDim,
activations.x.data() + token_idx * kModelDim, kModelDim);
MulByConst(kEmbScaling, activations.x.data() + token_idx * kModelDim,
kModelDim);
if constexpr (TConfig::kAbsolutePE) {
AddAbsolutePositionalEmbeddings(
activations.x.data() + token_idx * kModelDim, TConfig::kModelDim,
pos);
};
});
for (size_t layer = 0; layer < TConfig::kLayers; ++layer) {
auto type = TConfig::kLayerConfig[layer];
const auto* layer_weights = weights.GetLayer(layer);
size_t layer_of_type =
NumLayersOfTypeBefore(TConfig::kLayerConfig, type, layer);
for (size_t token_idx = 0; token_idx < num_tokens; ++token_idx) {
RMSNorm(activations.x.data() + token_idx * kModelDim,
layer_weights->pre_attention_norm_scale.data(),
activations.pre_att_rms_out.data() + token_idx * kModelDim,
kModelDim);
}
if (type == LayerAttentionType::kGemma) {
Attention<kBatchSize>(pos, num_tokens, layer_of_type, activations,
layer_weights, kv_cache, pool);
} else {
GriffinRecurrent<kBatchSize>(pos, num_tokens, layer_of_type, activations,
layer_weights, kv_cache, pool);
}
pool.Run(0, num_tokens, [&](const uint64_t token_idx,
size_t /*thread*/) HWY_ATTR {
if (TConfig::kPostNormScale) {
RMSNormInplace(layer_weights->post_attention_norm_scale.data(),
activations.att_post2.data() + token_idx * kModelDim,
kModelDim);
}
AddFrom(activations.att_post2.data() + token_idx * kModelDim,
activations.x.data() + token_idx * kModelDim, kModelDim);
RMSNorm(activations.x.data() + token_idx * kModelDim,
layer_weights->pre_ffw_norm_scale.data(),
activations.bf_pre_ffw_rms_out.data() + token_idx * kModelDim,
kModelDim);
});
FFW<kBatchSize>(activations, num_tokens, layer_weights, pool);
for (size_t token_idx = 0; token_idx < num_tokens; ++token_idx) {
if (TConfig::kPostNormScale) {
RMSNormInplace(layer_weights->post_ffw_norm_scale.data(),
activations.ffw_out.data() + token_idx * kModelDim,
kModelDim);
}
AddFrom(activations.ffw_out.data() + token_idx * kModelDim,
activations.x.data() + token_idx * kModelDim, kModelDim);
}
} // foreach layer
pool.Run(
0, num_tokens, [&](const uint64_t token_idx, size_t /*thread*/) HWY_ATTR {
RMSNormInplace(weights.final_norm_scale.data(),
activations.x.data() + token_idx * kModelDim, kModelDim);
});
}
// n = 1 specialization
template <typename WeightArrayT, class TConfig>
HWY_NOINLINE void Transformer(int token, size_t pos,
const WeightArrayT& weights,
Activations<TConfig, 1>& activations,
KVCache& kv_cache, hwy::ThreadPool& pool,
LayersOutputT* layers_output) {
if (layers_output != nullptr) {
float token_f = token;
(*layers_output)(pos, "Tokens", &token_f, 1);
}
static constexpr size_t kModelDim = TConfig::kModelDim;
Decompress(weights.embedder_input_embedding, token * kModelDim,
activations.x.data(), kModelDim);
GEMMA_CONSTEXPR_EMBSCALING const float kEmbScaling =
EmbeddingScaling<TConfig>();
MulByConst(kEmbScaling, activations.x.data(), kModelDim);
if constexpr (TConfig::kAbsolutePE) {
AddAbsolutePositionalEmbeddings(activations.x.data(), TConfig::kModelDim,
pos);
};
for (size_t layer = 0; layer < TConfig::kLayers; ++layer) {
auto type = TConfig::kLayerConfig[layer];
const auto* layer_weights = weights.GetLayer(layer);
size_t layer_of_type =
NumLayersOfTypeBefore(TConfig::kLayerConfig, type, layer);
RMSNorm(activations.x.data(),
layer_weights->pre_attention_norm_scale.data(),
activations.pre_att_rms_out.data(), kModelDim);
if (type == LayerAttentionType::kGemma) {
Attention<1>(pos, 1, layer_of_type, activations, layer_weights, kv_cache,
pool);
} else {
GriffinRecurrent<1>(pos, 1, layer_of_type, activations, layer_weights,
kv_cache, pool);
}
if (TConfig::kPostNormScale) {
RMSNormInplace(layer_weights->post_attention_norm_scale.data(),
activations.att_post2.data(), kModelDim);
}
AddFrom(activations.att_post2.data(), activations.x.data(), kModelDim);
RMSNorm(activations.x.data(), layer_weights->pre_ffw_norm_scale.data(),
activations.bf_pre_ffw_rms_out.data(), kModelDim);
FFW<1>(activations, /* num_tokens = */ 1, layer_weights, pool);
if (TConfig::kPostNormScale) {
RMSNormInplace(layer_weights->post_ffw_norm_scale.data(),
activations.ffw_out.data(), kModelDim);
}
AddFrom(activations.ffw_out.data(), activations.x.data(), kModelDim);
if (layers_output != nullptr) {
std::string block_name = "blocks." + std::to_string(layer);
(*layers_output)(pos, block_name, activations.x.data(), kModelDim);
}
}
RMSNormInplace(weights.final_norm_scale.data(), activations.x.data(),
kModelDim);
if (layers_output != nullptr) {
(*layers_output)(pos, "final_norm", activations.x.data(), kModelDim);
}
}
template <class TConfig>
void RangeChecks(size_t& max_tokens, size_t& max_generated_tokens,
size_t& prompt_size) {
if (!TConfig::kUseLocalAttention) {
if (max_tokens > TConfig::kSeqLen) {
fprintf(stderr, "WARNING: max_tokens %zu > kSeqLen %d, truncating.\n",
max_tokens, TConfig::kSeqLen);
max_tokens = static_cast<size_t>(TConfig::kSeqLen);
}
}
if (max_generated_tokens > max_tokens) {
fprintf(stderr,
"WARNING: max_generated_tokens %zu > max_tokens %zu, truncating.\n",
max_generated_tokens, max_tokens);
max_generated_tokens = max_tokens - 1;
}
if (!TConfig::kUseLocalAttention) {
if (prompt_size + max_generated_tokens > max_tokens) {
fprintf(stderr,
"WARNING: prompt_size %zu + max_generated_tokens %zu > "
"max_tokens %zu, truncating to ",
prompt_size, max_generated_tokens, max_tokens);
prompt_size = std::min(prompt_size, max_tokens - max_generated_tokens);
fprintf(stderr, "%zu\n", prompt_size);
}
}
}
template <class TConfig>
const WeightsT<TConfig>& GetWeights(const ByteStorageT& weights_u8) {
return *reinterpret_cast<const WeightsT<TConfig>*>(weights_u8.get());
}
template <class TConfig, size_t kBatchSize>
Activations<TConfig, kBatchSize>& GetActivations(const ByteStorageT& state_u8) {
return *reinterpret_cast<Activations<TConfig, kBatchSize>*>(state_u8.get());
}
} // namespace
template <class TConfig>
void GenerateT(const ByteStorageT& weights_u8, const ByteStorageT& prefill_u8,
const ByteStorageT& decode_u8,
const RuntimeConfig& runtime_config,
const std::vector<int>& prompt, size_t pos, KVCache& kv_cache,
hwy::ThreadPool& pool, TimingInfo& timing_info,
LayersOutputT* layers_output) {
const WeightsT<TConfig>& weights = GetWeights<TConfig>(weights_u8);
auto& prefill_activations =
GetActivations<TConfig, kPrefillBatchSize>(prefill_u8);
auto& activations = GetActivations<TConfig, 1>(decode_u8);
static constexpr size_t kVocabSize = TConfig::kVocabSize;
size_t prompt_size = prompt.size();
size_t max_tokens = runtime_config.max_tokens;
size_t max_generated_tokens = runtime_config.max_generated_tokens;
RangeChecks<TConfig>(max_tokens, max_generated_tokens, prompt_size);
if (pos >= max_tokens) {
fprintf(stderr, "Warning: pos %zu >= max_tokens %zu, aborting.\n", pos,
max_tokens);
return;
}
HWY_ASSERT(prompt_size > 0);
// pos indexes the KV cache. In the first turn of a chat, pos = 0.
//
// After the first turn, pos gets passed in with > 0 corresponding to the
// current token position in the KV cache.
//
// pos_offset keeps track of the relative position within the turn, starting
// at 0 each turn. During prefill, pos_offset corresponds to the index into
// the prompt vector.
//
// In single-turn (non-chat) usage, pos and pos_offset start at 0 and are
// always equal.
size_t pos_offset = 0; // offset relative to pos
const double prefill_start = hwy::platform::Now();
// Prefill stops before prompt_size - 1 since the last prompt token is the
// first input token for generation.
while (pos_offset < prompt_size - 1) {
const size_t batch_size =
std::min(kPrefillBatchSize, prompt_size - 1 - pos_offset);
HWY_DASSERT(batch_size <= kPrefillBatchSize);
HWY_DASSERT(pos_offset + batch_size <= prompt_size - 1);
const int* batch_tokens = prompt.data() + pos_offset;
Prefill<kPrefillBatchSize>(batch_tokens, batch_size, pos, weights,
prefill_activations, kv_cache, pool);
for (size_t idx = 0; idx < batch_size; ++idx) {
if (!runtime_config.stream_token(batch_tokens[idx], 0.0f)) return;
}
pos += batch_size;
pos_offset += batch_size;
}
if (runtime_config.verbosity >= 2) {
const double prefill_end = hwy::platform::Now();
timing_info.prefill_tok_sec =
static_cast<double>(pos_offset) / (prefill_end - prefill_start);
}
const double gen_start = hwy::platform::Now();
HWY_DASSERT(pos_offset == prompt_size - 1);
size_t pos_gen_start = pos_offset;
int token = prompt.at(pos_offset);
runtime_config.stream_token(token, 0);
for (size_t generate_pos = 0;
pos < max_tokens && generate_pos < max_generated_tokens;
++pos, ++pos_offset, ++generate_pos) {
const bool is_generating_phase = pos_offset >= prompt_size - 1;
Transformer(token, pos, weights, activations, kv_cache, pool,
layers_output);
float* final_activation = activations.x.data();
// The condition below is always true if we are doing Prefill above.
// We keep it here for clarity so that the code is correct even if Prefill
// is disabled.
if (is_generating_phase) {
PROFILER_ZONE("Gen.Embedding");
// Generation phase
MatVec<kVocabSize, TConfig::kModelDim>(
weights.embedder_input_embedding, 0, final_activation,
activations.even_odd.data(), activations.logits.data(), pool);
LogitsSoftCap(30.0f, activations.logits.data(), kVocabSize);
// Barrier: must have all logits so we can subtract max.
Softmax(activations.logits.data(), kVocabSize);
if (runtime_config.sample_func) {
token = (*runtime_config.sample_func)(activations.logits.data(),
kVocabSize);
} else {
token = SampleTopK<TConfig::kTopK>(
activations.logits.data(), kVocabSize, *runtime_config.gen,
runtime_config.temperature, runtime_config.accept_token);
if (!runtime_config.stream_token(token, activations.logits[token])) {
token = runtime_config.eos_id;
}
}
if (generate_pos == 0) {
timing_info.time_to_first_token = hwy::platform::Now() - gen_start;
}
} else {
// We would take this branch if we were not doing Prefill but would
// process the tokens of the prompt one at a time.
token = prompt.at(pos_offset + 1);
if (!runtime_config.stream_token(token, 0)) {
token = runtime_config.eos_id;
}
}
if (token == runtime_config.eos_id) {
if (runtime_config.verbosity >= 2) {
const double gen_end = hwy::platform::Now();
timing_info.gen_tok_sec =
static_cast<double>(pos_offset - pos_gen_start) /
(gen_end - gen_start);
}
break;
}
}
}
} // namespace HWY_NAMESPACE
} // namespace gcpp
HWY_AFTER_NAMESPACE();
#if HWY_ONCE
namespace gcpp {
namespace {
template <typename TConfig>
struct AllocatePrefill {
ByteStorageT operator()() const {
return AllocateSizeof<Activations<TConfig, kPrefillBatchSize>>();
}
};
template <typename TConfig>
struct AllocateDecode {
ByteStorageT operator()() const {
return AllocateSizeof<Activations<TConfig, 1>>();
}
};
} // namespace
Gemma::Gemma(const Path& tokenizer_path, const Path& weights, Model model_type,
Type weight_type, hwy::ThreadPool& pool)
: pool_(pool),
tokenizer_(tokenizer_path),
model_type_(model_type),
weight_type_(weight_type) {
weights_u8_ = LoadWeights(weights, model_type, weight_type, pool);
prefill_u8_ = CallForModelAndWeight<AllocatePrefill>(model_type, weight_type);
decode_u8_ = CallForModelAndWeight<AllocateDecode>(model_type, weight_type);
}
Gemma::Gemma(GemmaTokenizer&& tokenizer, Model model_type, Type weight_type,
hwy::ThreadPool& pool)
: pool_(pool),
tokenizer_(std::move(tokenizer)),
model_type_(model_type),
weight_type_(weight_type) {
weights_u8_ =
CallForModelAndWeight<AllocateWeightsF>(model_type, weight_type, pool);
prefill_u8_ = CallForModelAndWeight<AllocatePrefill>(model_type, weight_type);
decode_u8_ = CallForModelAndWeight<AllocateDecode>(model_type, weight_type);
}
Gemma::~Gemma() {
CallForModelAndWeight<DeleteLayersPtrs>(model_type_, weight_type_,
weights_u8_);
}
void Gemma::Generate(const RuntimeConfig& runtime_config,
const std::vector<int>& prompt, size_t start_pos,
KVCache& kv_cache, TimingInfo& timing_info,
LayersOutputT* layers_output) {
pool_.SetWaitMode(hwy::PoolWaitMode::kSpin);
GEMMA_EXPORT_AND_DISPATCH(
model_type_, weight_type_, GenerateT,
(weights_u8_, prefill_u8_, decode_u8_, runtime_config, prompt, start_pos,
kv_cache, pool_, timing_info, layers_output));
pool_.SetWaitMode(hwy::PoolWaitMode::kBlock);
}
} // namespace gcpp
#endif // HWY_ONCE