Grok 10.0.3
highway.h
Go to the documentation of this file.
1// Copyright 2020 Google LLC
2// SPDX-License-Identifier: Apache-2.0
3//
4// Licensed under the Apache License, Version 2.0 (the "License");
5// you may not use this file except in compliance with the License.
6// You may obtain a copy of the License at
7//
8// http://www.apache.org/licenses/LICENSE-2.0
9//
10// Unless required by applicable law or agreed to in writing, software
11// distributed under the License is distributed on an "AS IS" BASIS,
12// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13// See the License for the specific language governing permissions and
14// limitations under the License.
15
16// This include guard is checked by foreach_target, so avoid the usual _H_
17// suffix to prevent copybara from renaming it. NOTE: ops/*-inl.h are included
18// after/outside this include guard.
19#ifndef HWY_HIGHWAY_INCLUDED
20#define HWY_HIGHWAY_INCLUDED
21
22// Main header required before using vector types.
23
24#include "hwy/base.h"
25#include "hwy/targets.h"
26
27namespace hwy {
28
29// API version (https://semver.org/); keep in sync with CMakeLists.txt.
30#define HWY_MAJOR 0
31#define HWY_MINOR 17
32#define HWY_PATCH 0
33
34//------------------------------------------------------------------------------
35// Shorthand for tags (defined in shared-inl.h) used to select overloads.
36// Note that ScalableTag<T> is preferred over HWY_FULL, and CappedTag<T, N> over
37// HWY_CAPPED(T, N).
38
39// HWY_FULL(T[,LMUL=1]) is a native vector/group. LMUL is the number of
40// registers in the group, and is ignored on targets that do not support groups.
41#define HWY_FULL1(T) hwy::HWY_NAMESPACE::ScalableTag<T>
42#define HWY_FULL2(T, LMUL) \
43 hwy::HWY_NAMESPACE::ScalableTag<T, CeilLog2(HWY_MAX(0, LMUL))>
44#define HWY_3TH_ARG(arg1, arg2, arg3, ...) arg3
45// Workaround for MSVC grouping __VA_ARGS__ into a single argument
46#define HWY_FULL_RECOMPOSER(args_with_paren) HWY_3TH_ARG args_with_paren
47// Trailing comma avoids -pedantic false alarm
48#define HWY_CHOOSE_FULL(...) \
49 HWY_FULL_RECOMPOSER((__VA_ARGS__, HWY_FULL2, HWY_FULL1, ))
50#define HWY_FULL(...) HWY_CHOOSE_FULL(__VA_ARGS__())(__VA_ARGS__)
51
52// Vector of up to MAX_N lanes. It's better to use full vectors where possible.
53#define HWY_CAPPED(T, MAX_N) hwy::HWY_NAMESPACE::CappedTag<T, MAX_N>
54
55//------------------------------------------------------------------------------
56// Export user functions for static/dynamic dispatch
57
58// Evaluates to 0 inside a translation unit if it is generating anything but the
59// static target (the last one if multiple targets are enabled). Used to prevent
60// redefinitions of HWY_EXPORT. Unless foreach_target.h is included, we only
61// compile once anyway, so this is 1 unless it is or has been included.
62#ifndef HWY_ONCE
63#define HWY_ONCE 1
64#endif
65
66// HWY_STATIC_DISPATCH(FUNC_NAME) is the namespace-qualified FUNC_NAME for
67// HWY_STATIC_TARGET (the only defined namespace unless HWY_TARGET_INCLUDE is
68// defined), and can be used to deduce the return type of Choose*.
69#if HWY_STATIC_TARGET == HWY_SCALAR
70#define HWY_STATIC_DISPATCH(FUNC_NAME) N_SCALAR::FUNC_NAME
71#elif HWY_STATIC_TARGET == HWY_EMU128
72#define HWY_STATIC_DISPATCH(FUNC_NAME) N_EMU128::FUNC_NAME
73#elif HWY_STATIC_TARGET == HWY_RVV
74#define HWY_STATIC_DISPATCH(FUNC_NAME) N_RVV::FUNC_NAME
75#elif HWY_STATIC_TARGET == HWY_WASM_EMU256
76#define HWY_STATIC_DISPATCH(FUNC_NAME) N_WASM2::FUNC_NAME
77#elif HWY_STATIC_TARGET == HWY_WASM
78#define HWY_STATIC_DISPATCH(FUNC_NAME) N_WASM::FUNC_NAME
79#elif HWY_STATIC_TARGET == HWY_NEON
80#define HWY_STATIC_DISPATCH(FUNC_NAME) N_NEON::FUNC_NAME
81#elif HWY_STATIC_TARGET == HWY_SVE
82#define HWY_STATIC_DISPATCH(FUNC_NAME) N_SVE::FUNC_NAME
83#elif HWY_STATIC_TARGET == HWY_SVE2
84#define HWY_STATIC_DISPATCH(FUNC_NAME) N_SVE2::FUNC_NAME
85#elif HWY_STATIC_TARGET == HWY_SVE_256
86#define HWY_STATIC_DISPATCH(FUNC_NAME) N_SVE_256::FUNC_NAME
87#elif HWY_STATIC_TARGET == HWY_SVE2_128
88#define HWY_STATIC_DISPATCH(FUNC_NAME) N_SVE2_128::FUNC_NAME
89#elif HWY_STATIC_TARGET == HWY_PPC8
90#define HWY_STATIC_DISPATCH(FUNC_NAME) N_PPC8::FUNC_NAME
91#elif HWY_STATIC_TARGET == HWY_SSSE3
92#define HWY_STATIC_DISPATCH(FUNC_NAME) N_SSSE3::FUNC_NAME
93#elif HWY_STATIC_TARGET == HWY_SSE4
94#define HWY_STATIC_DISPATCH(FUNC_NAME) N_SSE4::FUNC_NAME
95#elif HWY_STATIC_TARGET == HWY_AVX2
96#define HWY_STATIC_DISPATCH(FUNC_NAME) N_AVX2::FUNC_NAME
97#elif HWY_STATIC_TARGET == HWY_AVX3
98#define HWY_STATIC_DISPATCH(FUNC_NAME) N_AVX3::FUNC_NAME
99#elif HWY_STATIC_TARGET == HWY_AVX3_DL
100#define HWY_STATIC_DISPATCH(FUNC_NAME) N_AVX3_DL::FUNC_NAME
101#endif
102
103// Dynamic dispatch declarations.
104
105template <typename RetType, typename... Args>
107 public:
108 typedef RetType(FunctionType)(Args...);
109
110 // A template function that when instantiated has the same signature as the
111 // function being called. This function initializes the global cache of the
112 // current supported targets mask used for dynamic dispatch and calls the
113 // appropriate function. Since this mask used for dynamic dispatch is a
114 // global cache, all the highway exported functions, even those exposed by
115 // different modules, will be initialized after this function runs for any one
116 // of those exported functions.
117 template <FunctionType* const table[]>
118 static RetType ChooseAndCall(Args... args) {
119 // If we are running here it means we need to update the chosen target.
120 ChosenTarget& chosen_target = GetChosenTarget();
121 chosen_target.Update(SupportedTargets());
122 return (table[chosen_target.GetIndex()])(args...);
123 }
124};
125
126// Factory function only used to infer the template parameters RetType and Args
127// from a function passed to the factory.
128template <typename RetType, typename... Args>
129FunctionCache<RetType, Args...> FunctionCacheFactory(RetType (*)(Args...)) {
130 return FunctionCache<RetType, Args...>();
131}
132
133// HWY_CHOOSE_*(FUNC_NAME) expands to the function pointer for that target or
134// nullptr is that target was not compiled.
135#if HWY_TARGETS & HWY_EMU128
136#define HWY_CHOOSE_FALLBACK(FUNC_NAME) &N_EMU128::FUNC_NAME
137#elif HWY_TARGETS & HWY_SCALAR
138#define HWY_CHOOSE_FALLBACK(FUNC_NAME) &N_SCALAR::FUNC_NAME
139#else
140// When HWY_SCALAR/HWY_EMU128 are not present and other targets were disabled at
141// runtime, fall back to the baseline with HWY_STATIC_DISPATCH().
142#define HWY_CHOOSE_FALLBACK(FUNC_NAME) &HWY_STATIC_DISPATCH(FUNC_NAME)
143#endif
144
145#if HWY_TARGETS & HWY_WASM_EMU256
146#define HWY_CHOOSE_WASM2(FUNC_NAME) &N_WASM2::FUNC_NAME
147#else
148#define HWY_CHOOSE_WASM2(FUNC_NAME) nullptr
149#endif
150
151#if HWY_TARGETS & HWY_WASM
152#define HWY_CHOOSE_WASM(FUNC_NAME) &N_WASM::FUNC_NAME
153#else
154#define HWY_CHOOSE_WASM(FUNC_NAME) nullptr
155#endif
156
157#if HWY_TARGETS & HWY_RVV
158#define HWY_CHOOSE_RVV(FUNC_NAME) &N_RVV::FUNC_NAME
159#else
160#define HWY_CHOOSE_RVV(FUNC_NAME) nullptr
161#endif
162
163#if HWY_TARGETS & HWY_NEON
164#define HWY_CHOOSE_NEON(FUNC_NAME) &N_NEON::FUNC_NAME
165#else
166#define HWY_CHOOSE_NEON(FUNC_NAME) nullptr
167#endif
168
169#if HWY_TARGETS & HWY_SVE
170#define HWY_CHOOSE_SVE(FUNC_NAME) &N_SVE::FUNC_NAME
171#else
172#define HWY_CHOOSE_SVE(FUNC_NAME) nullptr
173#endif
174
175#if HWY_TARGETS & HWY_SVE2
176#define HWY_CHOOSE_SVE2(FUNC_NAME) &N_SVE2::FUNC_NAME
177#else
178#define HWY_CHOOSE_SVE2(FUNC_NAME) nullptr
179#endif
180
181#if HWY_TARGETS & HWY_SVE_256
182#define HWY_CHOOSE_SVE_256(FUNC_NAME) &N_SVE_256::FUNC_NAME
183#else
184#define HWY_CHOOSE_SVE_256(FUNC_NAME) nullptr
185#endif
186
187#if HWY_TARGETS & HWY_SVE2_128
188#define HWY_CHOOSE_SVE2_128(FUNC_NAME) &N_SVE2_128::FUNC_NAME
189#else
190#define HWY_CHOOSE_SVE2_128(FUNC_NAME) nullptr
191#endif
192
193#if HWY_TARGETS & HWY_PPC8
194#define HWY_CHOOSE_PCC8(FUNC_NAME) &N_PPC8::FUNC_NAME
195#else
196#define HWY_CHOOSE_PPC8(FUNC_NAME) nullptr
197#endif
198
199#if HWY_TARGETS & HWY_SSSE3
200#define HWY_CHOOSE_SSSE3(FUNC_NAME) &N_SSSE3::FUNC_NAME
201#else
202#define HWY_CHOOSE_SSSE3(FUNC_NAME) nullptr
203#endif
204
205#if HWY_TARGETS & HWY_SSE4
206#define HWY_CHOOSE_SSE4(FUNC_NAME) &N_SSE4::FUNC_NAME
207#else
208#define HWY_CHOOSE_SSE4(FUNC_NAME) nullptr
209#endif
210
211#if HWY_TARGETS & HWY_AVX2
212#define HWY_CHOOSE_AVX2(FUNC_NAME) &N_AVX2::FUNC_NAME
213#else
214#define HWY_CHOOSE_AVX2(FUNC_NAME) nullptr
215#endif
216
217#if HWY_TARGETS & HWY_AVX3
218#define HWY_CHOOSE_AVX3(FUNC_NAME) &N_AVX3::FUNC_NAME
219#else
220#define HWY_CHOOSE_AVX3(FUNC_NAME) nullptr
221#endif
222
223#if HWY_TARGETS & HWY_AVX3_DL
224#define HWY_CHOOSE_AVX3_DL(FUNC_NAME) &N_AVX3_DL::FUNC_NAME
225#else
226#define HWY_CHOOSE_AVX3_DL(FUNC_NAME) nullptr
227#endif
228
229#define HWY_DISPATCH_TABLE(FUNC_NAME) \
230 HWY_CONCAT(FUNC_NAME, HighwayDispatchTable)
231
232// HWY_EXPORT(FUNC_NAME); expands to a static array that is used by
233// HWY_DYNAMIC_DISPATCH() to call the appropriate function at runtime. This
234// static array must be defined at the same namespace level as the function
235// it is exporting.
236// After being exported, it can be called from other parts of the same source
237// file using HWY_DYNAMIC_DISTPATCH(), in particular from a function wrapper
238// like in the following example:
239//
240// #include "hwy/highway.h"
241// HWY_BEFORE_NAMESPACE();
242// namespace skeleton {
243// namespace HWY_NAMESPACE {
244//
245// void MyFunction(int a, char b, const char* c) { ... }
246//
247// // NOLINTNEXTLINE(google-readability-namespace-comments)
248// } // namespace HWY_NAMESPACE
249// } // namespace skeleton
250// HWY_AFTER_NAMESPACE();
251//
252// namespace skeleton {
253// HWY_EXPORT(MyFunction); // Defines the dispatch table in this scope.
254//
255// void MyFunction(int a, char b, const char* c) {
256// return HWY_DYNAMIC_DISPATCH(MyFunction)(a, b, c);
257// }
258// } // namespace skeleton
259//
260
261#if HWY_IDE || ((HWY_TARGETS & (HWY_TARGETS - 1)) == 0)
262
263// Simplified version for IDE or the dynamic dispatch case with only one target.
264// This case still uses a table, although of a single element, to provide the
265// same compile error conditions as with the dynamic dispatch case when multiple
266// targets are being compiled.
267#define HWY_EXPORT(FUNC_NAME) \
268 HWY_MAYBE_UNUSED static decltype(&HWY_STATIC_DISPATCH(FUNC_NAME)) const \
269 HWY_DISPATCH_TABLE(FUNC_NAME)[1] = {&HWY_STATIC_DISPATCH(FUNC_NAME)}
270#define HWY_DYNAMIC_DISPATCH(FUNC_NAME) HWY_STATIC_DISPATCH(FUNC_NAME)
271
272#else
273
274// Dynamic dispatch case with one entry per dynamic target plus the fallback
275// target and the initialization wrapper.
276#define HWY_EXPORT(FUNC_NAME) \
277 static decltype(&HWY_STATIC_DISPATCH(FUNC_NAME)) const HWY_DISPATCH_TABLE( \
278 FUNC_NAME)[HWY_MAX_DYNAMIC_TARGETS + 2] = { \
279 /* The first entry in the table initializes the global cache and \
280 * calls the appropriate function. */ \
281 &decltype(hwy::FunctionCacheFactory(&HWY_STATIC_DISPATCH( \
282 FUNC_NAME)))::ChooseAndCall<HWY_DISPATCH_TABLE(FUNC_NAME)>, \
283 HWY_CHOOSE_TARGET_LIST(FUNC_NAME), \
284 HWY_CHOOSE_FALLBACK(FUNC_NAME), \
285 }
286#define HWY_DYNAMIC_DISPATCH(FUNC_NAME) \
287 (*(HWY_DISPATCH_TABLE(FUNC_NAME)[hwy::GetChosenTarget().GetIndex()]))
288
289#endif // HWY_IDE || ((HWY_TARGETS & (HWY_TARGETS - 1)) == 0)
290
291// DEPRECATED names; please use HWY_HAVE_* instead.
292#define HWY_CAP_INTEGER64 HWY_HAVE_INTEGER64
293#define HWY_CAP_FLOAT16 HWY_HAVE_FLOAT16
294#define HWY_CAP_FLOAT64 HWY_HAVE_FLOAT64
295
296} // namespace hwy
297
298#endif // HWY_HIGHWAY_INCLUDED
299
300//------------------------------------------------------------------------------
301
302// NOTE: the following definitions and ops/*.h depend on HWY_TARGET, so we want
303// to include them once per target, which is ensured by the toggle check.
304// Because ops/*.h are included under it, they do not need their own guard.
305#if defined(HWY_HIGHWAY_PER_TARGET) == defined(HWY_TARGET_TOGGLE)
306#ifdef HWY_HIGHWAY_PER_TARGET
307#undef HWY_HIGHWAY_PER_TARGET
308#else
309#define HWY_HIGHWAY_PER_TARGET
310#endif
311
312// These define ops inside namespace hwy::HWY_NAMESPACE.
313#if HWY_TARGET == HWY_SSSE3 || HWY_TARGET == HWY_SSE4
314#include "hwy/ops/x86_128-inl.h"
315#elif HWY_TARGET == HWY_AVX2
316#include "hwy/ops/x86_256-inl.h"
317#elif HWY_TARGET == HWY_AVX3 || HWY_TARGET == HWY_AVX3_DL
318#include "hwy/ops/x86_512-inl.h"
319#elif HWY_TARGET == HWY_PPC8
320#error "PPC is not yet supported"
321#elif HWY_TARGET == HWY_NEON
322#include "hwy/ops/arm_neon-inl.h"
323#elif HWY_TARGET == HWY_SVE || HWY_TARGET == HWY_SVE2 || \
324 HWY_TARGET == HWY_SVE_256 || HWY_TARGET == HWY_SVE2_128
325#include "hwy/ops/arm_sve-inl.h"
326#elif HWY_TARGET == HWY_WASM_EMU256
327#include "hwy/ops/wasm_256-inl.h"
328#elif HWY_TARGET == HWY_WASM
329#include "hwy/ops/wasm_128-inl.h"
330#elif HWY_TARGET == HWY_RVV
331#include "hwy/ops/rvv-inl.h"
332#elif HWY_TARGET == HWY_EMU128
333#include "hwy/ops/emu128-inl.h"
334#elif HWY_TARGET == HWY_SCALAR
335#include "hwy/ops/scalar-inl.h"
336#else
337#pragma message("HWY_TARGET does not match any known target")
338#endif // HWY_TARGET
339
341
342#endif // HWY_HIGHWAY_PER_TARGET
Definition: aligned_allocator.h:27
FunctionCache< RetType, Args... > FunctionCacheFactory(RetType(*)(Args...))
Definition: highway.h:129
HWY_DLLEXPORT ChosenTarget & GetChosenTarget()
HWY_DLLEXPORT uint32_t SupportedTargets()
Definition: targets.h:242
size_t HWY_INLINE GetIndex() const
Definition: targets.h:265
void Update(uint32_t targets)
Definition: targets.h:246
Definition: highway.h:106
RetType() FunctionType(Args...)
Definition: highway.h:108
static RetType ChooseAndCall(Args... args)
Definition: highway.h:118