gemma.cpp/ops/matmul.h

782 lines
28 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.
#ifndef THIRD_PARTY_GEMMA_CPP_OPS_MATMUL_H_
#define THIRD_PARTY_GEMMA_CPP_OPS_MATMUL_H_
// Non-SIMD part of MatMul: parallelization, allocation, and autotuning.
#include <stddef.h>
#include <stdint.h>
#include <vector>
// IWYU pragma: begin_exports
#include "util/basics.h"
#include "util/mat.h"
#include "util/threading_context.h"
#include "hwy/aligned_allocator.h" // Span
#include "hwy/base.h"
#include "hwy/bit_set.h"
#include "hwy/profiler.h"
// IWYU pragma: end_exports
namespace gcpp {
// The MatMul result C[r,c] is Dot(A.Row(r), B.Col(c)). To reduce the number of
// loads, we reuse the same A row for several B columns, which are also loaded
// once for several rows of C. Thus we produce one 'tile' of C at a time of
// dimensions `mr (<= kMaxMR)` x `kNR`. To keep FMA units busy, this should be
// at least the product of the FMA latency (3..5) times the throughput (2).
// This and `mr` are limited by the number of registers, which is generally
// 32 but 16 for AVX2. `kNR` == 4 enables the `StoreInterleaved4` transpose in
// `MMAddHorizontalSumsIntoPartial`. We ensure `C.Cols() % kNR == 0`.
constexpr size_t kNR = 4;
class MMParallel {
public:
static constexpr size_t kMaxPackages = 4;
// `ctx` must outlive this object.
MMParallel(ThreadingContext& ctx) : ctx_(ctx) {
HWY_DASSERT(ctx_.pools.NumPackages() <= kMaxPackages);
}
// Initial static partitioning of B rows across packages.
IndexRangePartition RangesOfNP(size_t max_packages, size_t N,
size_t sizeof_TC, size_t nr) const;
// For `BindB` and `BindC`.
size_t Node(size_t pkg_idx) const {
return ctx_.topology.GetCluster(pkg_idx, 0).Node();
}
// Calls `func(pkg_idx)` for each package in parallel.
template <class Func>
void ForPkg(const size_t max_packages, const Func& func) {
ctx_.pools.AllPackages().Run(
0, HWY_MIN(max_packages, ctx_.pools.NumPackages()),
[&](uint64_t task, size_t pkg_idx) {
HWY_DASSERT(task == pkg_idx);
(void)task;
func(pkg_idx);
});
}
// Cluster/CCX-aware parallel-for over B rows in `range_np`. `nx_multiple` is
// the granularity of per-cluster tasks. Calls `func(worker_range)`.
template <class Func>
void ForNP(const IndexRange& range_np, size_t nx_multiple, size_t inner_tasks,
size_t pkg_idx, const Func& func) {
HWY_DASSERT(1 <= inner_tasks && inner_tasks <= 4);
// Single cluster: parallel-for over static partition of `range_np`.
hwy::ThreadPool& all_clusters = ctx_.pools.AllClusters(pkg_idx);
const size_t num_clusters = all_clusters.NumWorkers();
if (num_clusters == 1) {
hwy::ThreadPool& cluster = ctx_.pools.Cluster(pkg_idx, 0);
const IndexRangePartition worker_ranges = StaticPartition(
range_np, cluster.NumWorkers() * inner_tasks, nx_multiple);
return ParallelizeOneRange(
worker_ranges, cluster,
[&](const IndexRange& worker_range, size_t /*thread*/) {
func(worker_range);
});
}
// Assign each cluster a sub-range of `range_np` (typically hundreds).
const IndexRangePartition nx_ranges =
StaticPartition(range_np, num_clusters, nx_multiple);
ParallelizeOneRange(
nx_ranges, all_clusters,
[&](const IndexRange& nx_range, const size_t cluster_idx) {
hwy::ThreadPool& cluster = ctx_.pools.Cluster(pkg_idx, cluster_idx);
// Parallel-for over sub-ranges of `cluster_range` within the cluster.
const IndexRangePartition worker_ranges = StaticPartition(
nx_range, cluster.NumWorkers() * inner_tasks, nx_multiple);
ParallelizeOneRange(worker_ranges, cluster,
[&](const IndexRange& worker_range,
size_t /*thread*/) { func(worker_range); });
});
}
// Cluster/CCX-aware parallel-for over blocks (separate subranges of A and B
// rows). Calls `func(range_mc, range_nc)`.
template <class Func>
void ForRangesMC_NC(const IndexRangePartition& ranges_mc,
const IndexRangePartition& ranges_nc, size_t pkg_idx,
const Func& func) {
hwy::ThreadPool& all_clusters = ctx_.pools.AllClusters(pkg_idx);
// `all_clusters` is a pool with one worker per cluster in a package.
const size_t num_clusters = all_clusters.NumWorkers();
// Single (big) cluster: collapse two range indices into one parallel-for
// to reduce the number of fork-joins.
if (num_clusters == 1) {
const size_t cluster_idx = 0;
hwy::ThreadPool& cluster = ctx_.pools.Cluster(pkg_idx, cluster_idx);
// Low-batch: avoid Divide/Remainder.
if (HWY_UNLIKELY(ranges_mc.NumTasks() == 1)) {
return ParallelizeOneRange(
ranges_nc, cluster,
[&](const IndexRange& range_nc, size_t /*thread*/) {
func(ranges_mc.Range(0), range_nc);
});
} else {
return ParallelizeTwoRanges(
ranges_mc, ranges_nc, cluster,
[&](const IndexRange& range_mc, const IndexRange& range_nc,
size_t /*thread*/) { func(range_mc, range_nc); });
}
}
// Multiple clusters: N across clusters (both are usually the larger), and
// M within each cluster. We assume auto-tuning finds small MC/NC tasks.
ParallelizeOneRange(
ranges_nc, all_clusters,
[&](const IndexRange range_nc, size_t cluster_idx) {
hwy::ThreadPool& cluster = ctx_.pools.Cluster(pkg_idx, cluster_idx);
ParallelizeOneRange(
ranges_mc, cluster,
[&](const IndexRange& range_mc, size_t /*thread*/) {
func(range_mc, range_nc);
});
});
}
// Calls `func(row_a)` in parallel.
template <class Func>
void ForRangeMC(const IndexRange& range_mc, size_t pkg_idx,
const Func& func) {
ctx_.pools.Pool(pkg_idx).Run(
range_mc.begin(), range_mc.end(),
[&](uint64_t row_a, size_t /*thread*/) { func(row_a); });
}
private:
ThreadingContext& ctx_;
};
template <typename TC> // BF16/float for C, double for partial
void BindC(const Allocator& allocator, size_t M, const RowPtr<TC>& C,
MMParallel& parallel) {
if (!allocator.ShouldBind()) return;
const IndexRangePartition ranges_np =
parallel.RangesOfNP(MMParallel::kMaxPackages, C.Cols(), sizeof(TC), kNR);
const size_t quantum = allocator.Quantum<TC>();
bool ok = true;
for (size_t pkg_idx = 0; pkg_idx < ranges_np.NumTasks(); ++pkg_idx) {
const IndexRange& cols_c = ranges_np.Range(pkg_idx);
const size_t node = parallel.Node(pkg_idx);
for (size_t im = 0; im < M; ++im) {
// `BindMemory` requires page alignment.
const size_t begin = hwy::RoundUpTo(cols_c.begin(), quantum);
const size_t end = hwy::RoundDownTo(cols_c.end(), quantum);
ok &= allocator.BindMemory(C.Row(im) + begin, (end - begin) * sizeof(TC),
node);
}
}
if (HWY_UNLIKELY(!ok)) {
HWY_WARN("Failed to bind C (%zux%zu), %zu packages.", M, C.Cols(),
ranges_np.NumTasks());
}
}
// Per-package storage for packed A, and one global C-shaped `partial` for
// accumulating partial dot products (sections of K).
class MMStorage {
public:
// Compile-time bounds on matrix dimensions to enable pre-allocating storage
// and reusing it across `MatMul` calls. The resulting allocations are 256 MiB
// per package and 512 MiB, respectively.
static constexpr size_t kMaxM = 4096;
static constexpr size_t kMaxK = 64 * 1024;
static constexpr size_t kMaxN = 256 * 1024;
// Upper bound for per-worker B storage on the stack. Chosen such that one row
// of BF16 A and B fit in 32 KiB L1, but there may be `kMaxMR` and `kNR`.
static constexpr size_t kMaxKC = 8 * 1024;
MMStorage(const Allocator& allocator, MMParallel& parallel)
// Per-worker copies of `partial` would be wasteful. We instead allocate
// one instance of the maximum matrix extents because threads write at
// false-sharing-free granularity.
: partial_storage_(
AllocateAlignedRows<double>(allocator, Extents2D(kMaxM, kMaxN))),
// Same stride independent of the actual C.Cols() so we can pre-bind.
partial_(allocator, partial_storage_.All(), kMaxN,
StrideForCyclicOffsets(kMaxN, allocator.Quantum<double>())) {
// Per-package allocation so each can decompress A into its own copy.
parallel.ForPkg(MMParallel::kMaxPackages, [&](size_t pkg_idx) {
pkg_A_[pkg_idx] =
AllocateAlignedRows<BF16>(allocator, Extents2D(kMaxM, kMaxK));
if (allocator.ShouldBind()) {
const size_t node = parallel.Node(pkg_idx);
if (!allocator.BindMemory(pkg_A_[pkg_idx].All(),
pkg_A_[pkg_idx].NumBytes(), node)) {
HWY_WARN("Failed to bind memory for package %zu", pkg_idx);
}
}
});
// Avoid cross-package accesses.
BindC(allocator, kMaxM, partial_, parallel);
}
// Returns per-package matrix view. Non-const so that `RowVectorBatch` is
// non-const, because `RowPtr` requires a non-const pointer.
RowPtrBF A(const Allocator& allocator, size_t pkg_idx,
const Extents2D& extents) {
HWY_DASSERT(extents.rows <= kMaxM);
HWY_DASSERT(extents.cols <= kMaxK);
const size_t stride =
StrideForCyclicOffsets(extents.cols, allocator.Quantum<BF16>());
return RowPtrBF(allocator, pkg_A_[pkg_idx].All(), extents.cols, stride);
}
RowPtrD Partial() const { return partial_; }
private:
RowVectorBatch<BF16> pkg_A_[MMParallel::kMaxPackages];
RowVectorBatch<double> partial_storage_;
RowPtrD partial_;
};
//------------------------------------------------------------------------------
// Autotuning
// Naming convention: outer loop first, T suffix means threaded. This refers to
// the loops *around* `A2C0`, which contains loops over mc/kc. The outermost
// `ranges_np` loop across packages is implicit and applies to all of these.
//
// Parallelizing across K (A/B columns) is undesirable because the resulting
// partial dot products require synchronization or reduction across threads.
enum class MMOrder : uint8_t {
// Single M, parallel N, sequential K (inside the parallel section to
// reduce fork-joins). Similar to GotoBLAS, good for large N vs. M and K.
kNT_K,
// Specialization of `kNT_K` for a single K task with `kDirect`.
kNT,
// Parallelize over blocks of M and N: good when both are large. We no longer
// support `kMT_NT_K`: no advantage on Skylake, and `kNT_MT_K` is 1.5x as
// fast on Zen4.
kNT_MT_K,
kNT_MT, // Specialization of `kNT_MT_K` for a single K task with `kDirect`.
// Resident C (`kK_M_NT`) should be good for large K relative to M and N.
// However, it does not (much) outperform `kNT_K` on SKX and Zen4. There are
// no kN* because we expect M (batch size) to be small relative to K and N.
};
static inline bool IsBlock(MMOrder order) {
return order == MMOrder::kNT_MT_K || order == MMOrder::kNT_MT;
}
static inline bool IsOneKC(MMOrder order) {
return order == MMOrder::kNT || order == MMOrder::kNT_MT;
}
static inline const char* StringFromOrder(MMOrder order) {
switch (order) {
case MMOrder::kNT_K:
return "NT_K";
case MMOrder::kNT:
return "NT";
case MMOrder::kNT_MT_K:
return "NT_MT_K";
case MMOrder::kNT_MT:
return "NT_MT";
default:
return nullptr;
}
}
// How/where to write the A2C0 result. This determines the `tag` argument to
// that function, which governs whether we call `MMStoreHorizontalSumsIntoC` or
// `MMAddHorizontalSumsIntoPartial`.
enum class MMOut : uint8_t {
kCopy, // accumulate into partial, scale/add to C
kDirect, // single kc task, write directly to C
kParM // kCopy but parallel over M
// kParN is not better on SKX/Zen4.
};
static inline const char* StringFromOut(MMOut out) {
switch (out) {
case MMOut::kDirect:
return "Direct";
case MMOut::kCopy:
return "Copy";
case MMOut::kParM:
return "ParM";
default:
return nullptr;
}
}
// How to parallelize the per-package `DecompressA`. To reduce combinatorial
// explosion, we tune this separately from `MMConfig`.
enum class MMParA : uint8_t { kNone, kK1 = 1, kK2 = 2, kK4 = 4, kM };
static inline const char* StringFromParA(MMParA par_a) {
switch (par_a) {
case MMParA::kNone:
return "ParA0 ";
case MMParA::kK1:
return "ParAK1";
case MMParA::kK2:
return "ParAK2";
case MMParA::kK4:
return "ParAK4";
case MMParA::kM:
return "ParAM ";
default:
return nullptr;
}
}
// Possible configurations for the autotuner to choose from:
// `mr` := C rows to write at a time (< #registers / `kNR`),
// `kc` := A / B columns such that `mr` rows fit in L1,
// `mc` := A rows such that `kc` columns fit in L2,
// `nc` := B rows such that `kc` columns fit in L3 alongside `mc x nc` C.
// Also includes loop order and task granularity.
#pragma pack(push, 1)
class MMConfig {
public:
MMConfig() = default; // for std::vector
// `mr` is the number of A rows per call to `MMKernel::LoopKC`.
// `MMOrder` is how to parallelize the outer loops.
// `MMOut` is how/whether to parallelize filling the C result.
// `inner_tasks` chooses the within-cluster task granularity in `ForNP`.
MMConfig(size_t K, size_t N, size_t mr, size_t mc, size_t kc, size_t nc,
size_t kc_multiple, size_t nc_multiple, MMOrder order, MMOut out,
int inner_tasks)
: mr_(static_cast<uint32_t>(mr)),
mc_(static_cast<uint32_t>(mc)),
kc_(static_cast<uint32_t>(kc)),
nc_(static_cast<uint32_t>(nc)),
nc_multiple_(static_cast<uint32_t>(nc_multiple)),
kc_multiple_(static_cast<uint32_t>(kc_multiple)),
order_(order),
out_(out),
inner_tasks_(static_cast<uint8_t>(inner_tasks)),
reserved_{} {
HWY_DASSERT(mr == 1 || mr == 2 || mr == 4);
if (mc % mr != 0) {
HWY_WARN("mc %zu not a multiple of mr %zu", mc, mr);
}
// Do not warn for single-kc tasks; some models unfortunately have K which
// are not multiples of `kc_multiple`.
if (kc != K && (kc % kc_multiple) != 0) {
HWY_WARN("kc %zu not a multiple of kc_multiple %zu", kc, kc_multiple);
}
if (nc != N && (nc % nc_multiple) != 0) {
HWY_WARN("nc %zu not a multiple of nc_multiple %zu", nc, nc_multiple);
}
HWY_DASSERT(StringFromOrder(order_) != nullptr);
HWY_DASSERT(StringFromOut(out_) != nullptr);
HWY_DASSERT(1 <= inner_tasks && inner_tasks <= 4);
}
// Splits M/N into blocks which are visited sequentially or in parallel.
// K is always sequential, see `MMOrder`.
IndexRangePartition RangesOfMC(size_t M) const {
return MaxSizePartition(IndexRange(0, M), mc_, mr_);
}
IndexRangePartition RangesOfKC(size_t K) const {
return MaxSizePartition(IndexRange(0, K), kc_, kc_multiple_);
}
IndexRangePartition RangesOfNC(IndexRange range_np) const {
return MaxSizePartition(range_np, nc_, nc_multiple_);
}
MMOrder Order() const { return order_; }
MMOut Out() const { return out_; }
// No `OuterTasks` because static partitioning across clusters is sufficient.
size_t InnerTasks() const { return static_cast<size_t>(inner_tasks_); }
// Accessors for printing autotune result.
size_t MR() const { return static_cast<size_t>(mr_); }
size_t MC() const { return static_cast<size_t>(mc_); }
size_t KC() const { return static_cast<size_t>(kc_); }
size_t NC() const { return static_cast<size_t>(nc_); }
private:
// Somewhat-compressed representation because MMCandidates may return dozens.
uint32_t mr_;
uint32_t mc_;
uint32_t kc_;
uint32_t nc_;
uint32_t nc_multiple_;
uint32_t kc_multiple_;
MMOrder order_;
MMOut out_;
uint8_t inner_tasks_;
HWY_MAYBE_UNUSED uint8_t reserved_[5];
};
static_assert(sizeof(MMConfig) == 32); // for faster indexing
#pragma pack(pop)
std::vector<MMConfig> MMCandidates(const Allocator& allocator, size_t M,
size_t K, size_t N, size_t sizeof_TC,
size_t max_mr, size_t nr,
const IndexRangePartition& ranges_np,
bool print_config);
// State machine for choosing the best `TConfig`, which is `MMConfig` for the
// main MatMul autotuner.
// TODO: replace with hwy/auto_tune.h.
template <typename TConfig>
class MMAutoTune {
public:
// Returns nullptr if not yet finished, otherwise the best config. Do not
// store this pointer because it can be invalidated.
const TConfig* Best() const { return best_; }
// If false, caller must call `SetCandidates` before `NextConfig`.
bool HasCandidates() const {
HWY_DASSERT(!Best());
return !candidates_.empty();
}
void SetCandidates(std::vector<TConfig> candidates) {
HWY_DASSERT(!HasCandidates());
candidates_.swap(candidates);
HWY_DASSERT(HasCandidates());
min_ticks_.resize(candidates_.size(), ~uint64_t{0});
}
// Returns the current `TConfig` to measure.
const TConfig& NextConfig() const {
HWY_DASSERT(!Best() && HasCandidates());
return candidates_[config_idx_];
}
// Returns the best ticks so far for this candidate. Negligible CPU time.
uint64_t NotifyTicks(uint64_t ticks) {
HWY_DASSERT(HasCandidates());
HWY_DASSERT(!skipped_.Get(config_idx_));
best_ticks_ = HWY_MIN(best_ticks_, ticks);
min_ticks_[config_idx_] = HWY_MIN(min_ticks_[config_idx_], ticks);
// Best so far. Save because we update `config_idx_` below.
const size_t my_best_ticks = min_ticks_[config_idx_];
const size_t my_idx = config_idx_;
// Advance/wrap around to next non-skipped config. Do this first because it
// updates `rounds_complete_`. To decorrelate measurements, we do not
// immediately re-measure the same config.
for (;;) {
++config_idx_;
if (HWY_UNLIKELY(config_idx_ == candidates_.size())) {
config_idx_ = 0;
++rounds_complete_;
}
// Guaranteed to terminate because `best_ticks_` is never worse than any
// other, hence is not skipped.
if (!skipped_.Get(config_idx_)) break;
}
// Disqualify from future `NextConfig` if the best of two measurements so
// far is sufficiently worse than `best_ticks_`. This tolerates some noise
// in the first or second measurement.
if (rounds_complete_ != 0 && my_best_ticks > 5 * best_ticks_ / 4) {
skipped_.Set(my_idx);
}
// After sufficient rounds, choose the winner.
if (rounds_complete_ == 4) {
for (size_t i = 0; i < candidates_.size(); ++i) {
worst_min_ticks_ = HWY_MAX(worst_min_ticks_, min_ticks_[i]);
if (min_ticks_[i] == best_ticks_) {
// Causes `Best()` to be non-null, hence `MatMul` will no longer call
// `NextConfig` for this shape.
best_ = &candidates_[i];
config_idx_ = i; // just in case callers want to know which index.
}
}
HWY_DASSERT(best_ != nullptr); // no min_ticks_ matches best_ticks_
}
return my_best_ticks;
}
// Avoid printing the first two rounds, because those might be noisy and not
// yet skipped.
bool ShouldPrint() { return rounds_complete_ > 2; }
// Only valid after Best() is non-null. Used to compute the autotuning gain.
uint64_t BestTicks() const { return best_ticks_; }
uint64_t WorstMinTicks() const { return worst_min_ticks_; }
uint64_t FirstConfigTicks() const { return min_ticks_[0]; }
private:
const TConfig* best_ = nullptr;
std::vector<TConfig> candidates_;
// Use Min because threads are pinned, so we only expect additive noise.
std::vector<uint64_t> min_ticks_; // one per candidate
size_t config_idx_ = 0; // [0, candidates_.size())
size_t rounds_complete_ = 0;
uint64_t best_ticks_ = ~uint64_t{0};
uint64_t worst_min_ticks_ = 0;
hwy::BitSet4096<> skipped_;
};
//------------------------------------------------------------------------------
// Map of previously seen dimensions to index via linear search.
class MMKeys {
public:
using Key = uint64_t;
// KeyFromDims will only return this if all dims are zero, which is invalid.
static constexpr Key kPadding = 0;
// Compresses the dimensions into a single Key for faster comparison.
static Key KeyFromDims(size_t M, size_t K, size_t N) {
HWY_DASSERT(M < (Key{1} << 16)); // batch sizes are smaller
HWY_DASSERT(K < (Key{1} << 24));
HWY_DASSERT(N < (Key{1} << 24));
const Key key = static_cast<Key>(M) | (static_cast<Key>(K) << 16) |
(static_cast<Key>(N) << 40);
HWY_DASSERT(key != kPadding);
return key;
}
// We leave the search to callers so they can use dynamic-dispatched SIMD,
// which is not possible in this header.
hwy::Span<const Key> Keys() const {
return hwy::Span<const Key>(keys_.get(), num_unique_);
}
// Must only be called if not already present in `Keys()`.
void Append(Key key, const Allocator& allocator) {
// Dynamic allocation because the test checks many more dimensions than
// would be reasonable to pre-allocate. DIY for alignment and padding.
if (HWY_UNLIKELY(num_unique_ >= capacity_)) {
const size_t NU64 = allocator.VectorBytes() / sizeof(Key);
// Start at one vector so the size is always a multiple of N.
if (HWY_UNLIKELY(capacity_ == 0)) {
capacity_ = hwy::DivCeil(NU64, 2); // will be doubled below
}
capacity_ *= 2;
HWY_DASSERT(capacity_ >= num_unique_ + 1);
hwy::AlignedFreeUniquePtr<Key[]> new_keys =
hwy::AllocateAligned<Key>(capacity_);
hwy::CopyBytes(keys_.get(), new_keys.get(), num_unique_ * sizeof(Key));
// Pad for SIMD.
for (size_t i = num_unique_; i < hwy::RoundUpTo(num_unique_, NU64); ++i) {
new_keys[i] = kPadding;
}
keys_.swap(new_keys);
}
keys_[num_unique_++] = key;
}
private:
size_t capacity_ = 0;
size_t num_unique_ = 0;
hwy::AlignedFreeUniquePtr<Key[]> keys_;
};
// Per-MatMul-shape state.
struct MMPerKey {
MMPerKey(size_t max_packages, size_t N, size_t sizeof_TC, size_t nr,
MMParallel& parallel)
: ranges_np(parallel.RangesOfNP(max_packages, N, sizeof_TC, nr)) {}
// Only profile if enabled and the main autotuner finished (the par_a
// autotuner is per-package and we want to avoid synchronization).
bool WantProfile() const { return PROFILER_ENABLED != 0 && autotune.Best(); }
const IndexRangePartition ranges_np;
MMAutoTune<MMConfig> autotune;
MMAutoTune<MMParA> autotune_par_a[MMParallel::kMaxPackages];
};
// Stores state shared across MatMul calls. Non-copyable. `ctx` must outlive
// `MatMulEnv`.
struct MatMulEnv {
explicit MatMulEnv(ThreadingContext& ctx);
ThreadingContext& ctx;
bool have_timer_stop = false;
// Whether `MMCandidates()` should print the set of parameters.
bool print_config = false;
// Whether to print each config's speed during autotuning.
bool print_measurement = false;
// Whether to print the best config immediately after autotuning finished.
bool print_best = false;
MMParallel parallel;
MMStorage storage;
MMKeys keys;
std::vector<MMPerKey> per_key;
};
// Arguments to MatMul() that are independent of the A/B/C types.
// Reduces register pressure compared to individual values/references.
struct MMArgs {
MMArgs(MatMulEnv& env, MMPerKey& per_key, double scale,
const float* HWY_RESTRICT add, const RowPtrD& partial)
: env(&env),
per_key(&per_key),
scale(scale),
add(add),
partial(partial) {}
MatMulEnv* env;
MMPerKey* per_key;
double scale;
const float* HWY_RESTRICT add;
// Same size as C, threads write at false-sharing-free granularity.
RowPtrD partial;
};
// Wrapper over hwy::Zone that is only enabled when autotuning finished.
#if PROFILER_ENABLED
class MMZone {
using Zone = hwy::Zone;
static_assert(alignof(Zone) <= 8 && sizeof(Zone) <= 8);
public:
~MMZone() {
if (used_) {
Zone* zone = reinterpret_cast<Zone*>(&data_);
zone->~Zone();
}
}
// `name` must be a string literal.
void MaybeEnter(const char* name, const MMArgs& args) {
if (args.per_key->WantProfile()) {
new (&data_) Zone(name);
used_ = true;
}
}
private:
uint64_t data_ = 0;
bool used_ = false;
};
#else
struct MMZone {
void MaybeEnter(const char*, const MMArgs&) {}
};
#endif // PROFILER_ENABLED
// Used for the A and B arguments of `MatMul`, which are always const.
// Create via MakeConstMat. This differs from `RowPtr` in that it supports the
// `ofs` required for compressed T.
template <typename T>
struct ConstMat {
ConstMat() = default;
ConstMat(const T* ptr, Extents2D extents, size_t stride)
: ptr(ptr), extents(extents), stride(stride), ofs(0) {
HWY_DASSERT(ptr != nullptr);
HWY_DASSERT(stride >= extents.cols);
}
size_t Row(size_t r) const {
if constexpr (HWY_IS_DEBUG_BUILD) {
if (r >= extents.rows) {
HWY_ABORT("ConstMat::Row %zu out of bounds %zu", r, extents.rows);
}
}
return ofs + r * stride;
}
const Extents2D& Extents() const { return extents; }
size_t Stride() const { return stride; }
float Scale() const { return scale; }
// So that matvec-inl.h can use the same interface as MatPtrT:
size_t Rows() const { return extents.rows; }
size_t Cols() const { return extents.cols; }
// Shrinks the row-extent of this matrix view, i.e. reduces the view to a
// subrange of the original rows starting at row 0.
void ShrinkRows(size_t rows) {
HWY_ASSERT(rows <= extents.rows);
extents.rows = rows;
}
const T* HWY_RESTRICT ptr;
Extents2D extents;
size_t stride;
// `scale` allows expanding the smaller range of `SfpStream` to the original
// values. MatFromWeights sets this from `MatPtr`.
float scale = 1.0f;
// Offset to add to `ptr`; separate because T=NuqStream does not support
// pointer arithmetic. This is in units of weights, and does not have anything
// to do with the interleaved NUQ tables. It should be computed via `Row()`
// to take into account the stride.
size_t ofs;
};
// For deducing T.
template <typename T>
ConstMat<T> MakeConstMat(T* HWY_RESTRICT ptr, Extents2D extents,
size_t stride) {
return ConstMat<T>(ptr, extents, stride);
}
// For A argument to MatMul (activations).
template <typename T>
ConstMat<T> ConstMatFromBatch(size_t batch_size,
const RowVectorBatch<T>& row_vectors) {
HWY_DASSERT(batch_size <= row_vectors.BatchSize());
return MakeConstMat(const_cast<T*>(row_vectors.Const()),
Extents2D(batch_size, row_vectors.Cols()),
row_vectors.Stride());
}
template <typename T>
ConstMat<T> ConstMatFromWeights(const MatPtrT<T>& m) {
ConstMat<T> mat =
MakeConstMat(const_cast<T*>(m.Row(0)), m.Extents(), m.Stride());
mat.scale = m.Scale();
return mat;
}
template <typename TB>
void BindB(const Allocator& allocator, size_t N, size_t sizeof_TC,
const ConstMat<TB>& B, MMParallel& parallel) {
if (!allocator.ShouldBind()) return;
const IndexRangePartition ranges_np =
parallel.RangesOfNP(MMParallel::kMaxPackages, N, sizeof_TC, kNR);
const size_t quantum = allocator.Quantum<TB>();
for (size_t pkg_idx = 0; pkg_idx < ranges_np.NumTasks(); ++pkg_idx) {
const IndexRange& rows_b = ranges_np.Range(pkg_idx);
const size_t node = parallel.Node(pkg_idx);
uintptr_t begin =
reinterpret_cast<uintptr_t>(B.ptr + B.Row(rows_b.begin()));
uintptr_t end = begin + rows_b.Num() * B.Stride() * sizeof(TB);
// B is not yet guaranteed to have padded rows, so only bind the
// subset that is page-aligned.
begin = hwy::RoundUpTo(begin, quantum);
end = hwy::RoundDownTo(end, quantum);
if (HWY_LIKELY(begin != end)) {
allocator.BindMemory(reinterpret_cast<void*>(begin), end - begin, node);
}
}
}
} // namespace gcpp
#endif // THIRD_PARTY_GEMMA_CPP_OPS_MATMUL_H_