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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 09:22:09 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 09:22:09 +0000
commit43a97878ce14b72f0981164f87f2e35e14151312 (patch)
tree620249daf56c0258faa40cbdcf9cfba06de2a846 /third_party/highway/hwy/detect_targets.h
parentInitial commit. (diff)
downloadfirefox-43a97878ce14b72f0981164f87f2e35e14151312.tar.xz
firefox-43a97878ce14b72f0981164f87f2e35e14151312.zip
Adding upstream version 110.0.1.upstream/110.0.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/highway/hwy/detect_targets.h')
-rw-r--r--third_party/highway/hwy/detect_targets.h479
1 files changed, 479 insertions, 0 deletions
diff --git a/third_party/highway/hwy/detect_targets.h b/third_party/highway/hwy/detect_targets.h
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+// Copyright 2021 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
+//
+// http://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 HIGHWAY_HWY_DETECT_TARGETS_H_
+#define HIGHWAY_HWY_DETECT_TARGETS_H_
+
+// Defines targets and chooses which to enable.
+
+#include "hwy/detect_compiler_arch.h"
+
+//------------------------------------------------------------------------------
+// Optional configuration
+
+// See g3doc/quick_reference.md for documentation of these macros.
+
+// Uncomment to override the default baseline determined from predefined macros:
+// #define HWY_BASELINE_TARGETS (HWY_SSE4 | HWY_SCALAR)
+
+// Uncomment to override the default blocklist:
+// #define HWY_BROKEN_TARGETS HWY_AVX3
+
+// Uncomment to definitely avoid generating those target(s):
+// #define HWY_DISABLED_TARGETS HWY_SSE4
+
+// Uncomment to avoid emitting BMI/BMI2/FMA instructions (allows generating
+// AVX2 target for VMs which support AVX2 but not the other instruction sets)
+// #define HWY_DISABLE_BMI2_FMA
+
+// Uncomment to enable SSSE3/SSE4 on MSVC even if AVX is not enabled
+// #define HWY_WANT_SSSE3
+// #define HWY_WANT_SSE4
+
+//------------------------------------------------------------------------------
+// Targets
+
+// Unique bit value for each target. A lower value is "better" (e.g. more lanes)
+// than a higher value within the same group/platform - see HWY_STATIC_TARGET.
+//
+// All values are unconditionally defined so we can test HWY_TARGETS without
+// first checking the HWY_ARCH_*.
+//
+// The C99 preprocessor evaluates #if expressions using intmax_t types. This
+// holds at least 64 bits in practice (verified 2022-07-18 via Godbolt on
+// 32-bit clang/GCC/MSVC compilers for x86/Arm7/AArch32/RISC-V/WASM). We now
+// avoid overflow when computing HWY_TARGETS (subtracting one instead of
+// left-shifting 2^62), but still do not use bit 63 because it is the sign bit.
+
+// --------------------------- x86: 15 targets (+ one fallback)
+// Bits 0..6 reserved (7 targets)
+// Currently satisfiable by Ice Lake (VNNI, VPCLMULQDQ, VPOPCNTDQ, VBMI, VBMI2,
+// VAES, BITALG). Later to be added: BF16 (Cooper Lake). VP2INTERSECT is only in
+// Tiger Lake? We do not yet have uses for GFNI.
+#define HWY_AVX3_DL (1LL << 7) // see HWY_WANT_AVX3_DL below
+#define HWY_AVX3 (1LL << 8)
+#define HWY_AVX2 (1LL << 9)
+// Bit 10: reserved for AVX
+#define HWY_SSE4 (1LL << 11)
+#define HWY_SSSE3 (1LL << 12)
+// Bits 13..14 reserved for SSE3 or SSE2 (2 targets)
+// The highest bit in the HWY_TARGETS mask that a x86 target can have. Used for
+// dynamic dispatch. All x86 target bits must be lower or equal to
+// (1 << HWY_HIGHEST_TARGET_BIT_X86) and they can only use
+// HWY_MAX_DYNAMIC_TARGETS in total.
+#define HWY_HIGHEST_TARGET_BIT_X86 14
+
+// --------------------------- Arm: 15 targets (+ one fallback)
+// Bits 15..23 reserved (9 targets)
+#define HWY_SVE2_128 (1LL << 24) // specialized target (e.g. Arm N2)
+#define HWY_SVE_256 (1LL << 25) // specialized target (e.g. Arm V1)
+#define HWY_SVE2 (1LL << 26)
+#define HWY_SVE (1LL << 27)
+#define HWY_NEON (1LL << 28) // On A64, includes/requires AES
+// Bit 29 reserved (Helium?)
+#define HWY_HIGHEST_TARGET_BIT_ARM 29
+
+// --------------------------- RISC-V: 9 targets (+ one fallback)
+// Bits 30..36 reserved (7 targets)
+#define HWY_RVV (1LL << 37)
+// Bit 38 reserved
+#define HWY_HIGHEST_TARGET_BIT_RVV 38
+
+// --------------------------- Future expansion: 4 targets
+// Bits 39..42 reserved
+
+
+// --------------------------- IBM Power: 9 targets (+ one fallback)
+// Bits 43..48 reserved (6 targets)
+#define HWY_PPC8 (1LL << 49) // v2.07 or 3
+// Bits 50..51 reserved for prior VSX/AltiVec (2 targets)
+#define HWY_HIGHEST_TARGET_BIT_PPC 51
+
+// --------------------------- WebAssembly: 9 targets (+ one fallback)
+// Bits 52..57 reserved (6 targets)
+#define HWY_WASM_EMU256 (1LL << 58) // Experimental
+#define HWY_WASM (1LL << 59)
+// Bits 60 reserved
+#define HWY_HIGHEST_TARGET_BIT_WASM 60
+
+// --------------------------- Emulation: 2 targets
+
+#define HWY_EMU128 (1LL << 61)
+// We do not add/left-shift, so this will not overflow to a negative number.
+#define HWY_SCALAR (1LL << 62)
+#define HWY_HIGHEST_TARGET_BIT_SCALAR 62
+
+// Do not use bit 63 - would be confusing to have negative numbers.
+
+//------------------------------------------------------------------------------
+// Set default blocklists
+
+// Disabled means excluded from enabled at user's request. A separate config
+// macro allows disabling without deactivating the blocklist below.
+#ifndef HWY_DISABLED_TARGETS
+#define HWY_DISABLED_TARGETS 0
+#endif
+
+// Broken means excluded from enabled due to known compiler issues. Allow the
+// user to override this blocklist without any guarantee of success.
+#ifndef HWY_BROKEN_TARGETS
+
+// x86 clang-6: we saw multiple AVX2/3 compile errors and in one case invalid
+// SSE4 codegen (possibly only for msan), so disable all those targets.
+#if HWY_ARCH_X86 && (HWY_COMPILER_CLANG != 0 && HWY_COMPILER_CLANG < 700)
+#define HWY_BROKEN_TARGETS (HWY_SSE4 | HWY_AVX2 | HWY_AVX3 | HWY_AVX3_DL)
+// This entails a major speed reduction, so warn unless the user explicitly
+// opts in to scalar-only.
+#if !defined(HWY_COMPILE_ONLY_SCALAR)
+#pragma message("x86 Clang <= 6: define HWY_COMPILE_ONLY_SCALAR or upgrade.")
+#endif
+
+// 32-bit may fail to compile AVX2/3.
+#elif HWY_ARCH_X86_32
+#define HWY_BROKEN_TARGETS (HWY_AVX2 | HWY_AVX3 | HWY_AVX3_DL)
+
+// MSVC AVX3 support is buggy: https://github.com/Mysticial/Flops/issues/16
+#elif HWY_COMPILER_MSVC != 0
+#define HWY_BROKEN_TARGETS (HWY_AVX3 | HWY_AVX3_DL)
+
+// armv7be has not been tested and is not yet supported.
+#elif HWY_ARCH_ARM_V7 && \
+ (defined(__ARM_BIG_ENDIAN) || \
+ (defined(__BYTE_ORDER) && __BYTE_ORDER == __BIG_ENDIAN))
+#define HWY_BROKEN_TARGETS (HWY_NEON)
+
+// SVE[2] require recent clang or gcc versions.
+#elif (HWY_COMPILER_CLANG && HWY_COMPILER_CLANG < 1100) || \
+ (HWY_COMPILER_GCC_ACTUAL && HWY_COMPILER_GCC_ACTUAL < 1000)
+#define HWY_BROKEN_TARGETS (HWY_SVE | HWY_SVE2 | HWY_SVE_256 | HWY_SVE2_128)
+
+#else
+#define HWY_BROKEN_TARGETS 0
+#endif
+
+#endif // HWY_BROKEN_TARGETS
+
+// Enabled means not disabled nor blocklisted.
+#define HWY_ENABLED(targets) \
+ ((targets) & ~((HWY_DISABLED_TARGETS) | (HWY_BROKEN_TARGETS)))
+
+// Opt-out for EMU128 (affected by a GCC bug on multiple arches, fixed in 12.3:
+// see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106322). This is separate
+// from HWY_BROKEN_TARGETS because it affects the fallback target, which must
+// always be enabled. If 1, we instead choose HWY_SCALAR even without
+// HWY_COMPILE_ONLY_SCALAR being set.
+#if !defined(HWY_BROKEN_EMU128) // allow overriding
+#if (HWY_COMPILER_GCC_ACTUAL && HWY_COMPILER_GCC_ACTUAL < 1203) || \
+ defined(HWY_NO_LIBCXX)
+#define HWY_BROKEN_EMU128 1
+#else
+#define HWY_BROKEN_EMU128 0
+#endif
+#endif // HWY_BROKEN_EMU128
+
+//------------------------------------------------------------------------------
+// Detect baseline targets using predefined macros
+
+// Baseline means the targets for which the compiler is allowed to generate
+// instructions, implying the target CPU would have to support them. This does
+// not take the blocklist into account.
+
+#if defined(HWY_COMPILE_ONLY_SCALAR) || HWY_BROKEN_EMU128
+#define HWY_BASELINE_SCALAR HWY_SCALAR
+#else
+#define HWY_BASELINE_SCALAR HWY_EMU128
+#endif
+
+// Also check HWY_ARCH to ensure that simulating unknown platforms ends up with
+// HWY_TARGET == HWY_BASELINE_SCALAR.
+
+#if HWY_ARCH_WASM && defined(__wasm_simd128__)
+#if defined(HWY_WANT_WASM2)
+#define HWY_BASELINE_WASM HWY_WASM_EMU256
+#else
+#define HWY_BASELINE_WASM HWY_WASM
+#endif // HWY_WANT_WASM2
+#else
+#define HWY_BASELINE_WASM 0
+#endif
+
+// Avoid choosing the PPC target until we have an implementation.
+#if HWY_ARCH_PPC && defined(__VSX__) && 0
+#define HWY_BASELINE_PPC8 HWY_PPC8
+#else
+#define HWY_BASELINE_PPC8 0
+#endif
+
+#define HWY_BASELINE_SVE2 0
+#define HWY_BASELINE_SVE 0
+#define HWY_BASELINE_NEON 0
+
+#if HWY_ARCH_ARM
+
+#if defined(__ARM_FEATURE_SVE2)
+#undef HWY_BASELINE_SVE2 // was 0, will be re-defined
+// If user specified -msve-vector-bits=128, they assert the vector length is
+// 128 bits and we should use the HWY_SVE2_128 (more efficient for some ops).
+#if defined(__ARM_FEATURE_SVE_BITS) && __ARM_FEATURE_SVE_BITS == 128
+#define HWY_BASELINE_SVE2 HWY_SVE2_128
+// Otherwise we're not sure what the vector length will be. The baseline must be
+// unconditionally valid, so we can only assume HWY_SVE2. However, when running
+// on a CPU with 128-bit vectors, user code that supports dynamic dispatch will
+// still benefit from HWY_SVE2_128 because we add it to HWY_ATTAINABLE_TARGETS.
+#else
+#define HWY_BASELINE_SVE2 HWY_SVE2
+#endif // __ARM_FEATURE_SVE_BITS
+#endif // __ARM_FEATURE_SVE2
+
+#if defined(__ARM_FEATURE_SVE)
+#undef HWY_BASELINE_SVE // was 0, will be re-defined
+// See above. If user-specified vector length matches our optimization, use it.
+#if defined(__ARM_FEATURE_SVE_BITS) && __ARM_FEATURE_SVE_BITS == 256
+#define HWY_BASELINE_SVE HWY_SVE_256
+#else
+#define HWY_BASELINE_SVE HWY_SVE
+#endif // __ARM_FEATURE_SVE_BITS
+#endif // __ARM_FEATURE_SVE
+
+// GCC 4.5.4 only defines __ARM_NEON__; 5.4 defines both.
+#if defined(__ARM_NEON__) || defined(__ARM_NEON)
+#undef HWY_BASELINE_NEON
+#define HWY_BASELINE_NEON HWY_NEON
+#endif
+
+#endif // HWY_ARCH_ARM
+
+// Special handling for MSVC because it has fewer predefined macros:
+#if HWY_COMPILER_MSVC
+
+// 1) We can only be sure SSSE3/SSE4 are enabled if AVX is:
+// https://stackoverflow.com/questions/18563978/.
+#if defined(__AVX__)
+#define HWY_CHECK_SSSE3 1
+#define HWY_CHECK_SSE4 1
+#else
+#define HWY_CHECK_SSSE3 0
+#define HWY_CHECK_SSE4 0
+#endif
+
+// 2) Cannot check for PCLMUL/AES and BMI2/FMA/F16C individually; we assume
+// PCLMUL/AES are available if SSE4 is, and BMI2/FMA/F16C if AVX2 is.
+#define HWY_CHECK_PCLMUL_AES 1
+#define HWY_CHECK_BMI2_FMA 1
+#define HWY_CHECK_F16C 1
+
+#else // non-MSVC
+
+#if defined(__SSSE3__)
+#define HWY_CHECK_SSSE3 1
+#else
+#define HWY_CHECK_SSSE3 0
+#endif
+
+#if defined(__SSE4_1__) && defined(__SSE4_2__)
+#define HWY_CHECK_SSE4 1
+#else
+#define HWY_CHECK_SSE4 0
+#endif
+
+// If these are disabled, they should not gate the availability of SSE4/AVX2.
+#if defined(HWY_DISABLE_PCLMUL_AES) || (defined(__PCLMUL__) && defined(__AES__))
+#define HWY_CHECK_PCLMUL_AES 1
+#else
+#define HWY_CHECK_PCLMUL_AES 0
+#endif
+
+#if defined(HWY_DISABLE_BMI2_FMA) || (defined(__BMI2__) && defined(__FMA__))
+#define HWY_CHECK_BMI2_FMA 1
+#else
+#define HWY_CHECK_BMI2_FMA 0
+#endif
+
+#if defined(HWY_DISABLE_F16C) || defined(__F16C__)
+#define HWY_CHECK_F16C 1
+#else
+#define HWY_CHECK_F16C 0
+#endif
+
+#endif // non-MSVC
+
+#if HWY_ARCH_X86 && (HWY_WANT_SSSE3 || HWY_CHECK_SSSE3)
+#define HWY_BASELINE_SSSE3 HWY_SSSE3
+#else
+#define HWY_BASELINE_SSSE3 0
+#endif
+
+#if HWY_ARCH_X86 && (HWY_WANT_SSE4 || (HWY_CHECK_SSE4 && HWY_CHECK_PCLMUL_AES))
+#define HWY_BASELINE_SSE4 HWY_SSE4
+#else
+#define HWY_BASELINE_SSE4 0
+#endif
+
+#if HWY_BASELINE_SSE4 != 0 && HWY_CHECK_BMI2_FMA && HWY_CHECK_F16C && \
+ defined(__AVX2__)
+#define HWY_BASELINE_AVX2 HWY_AVX2
+#else
+#define HWY_BASELINE_AVX2 0
+#endif
+
+// Require everything in AVX2 plus AVX-512 flags (also set by MSVC)
+#if HWY_BASELINE_AVX2 != 0 && defined(__AVX512F__) && defined(__AVX512BW__) && \
+ defined(__AVX512DQ__) && defined(__AVX512VL__)
+#define HWY_BASELINE_AVX3 HWY_AVX3
+#else
+#define HWY_BASELINE_AVX3 0
+#endif
+
+// TODO(janwas): not yet known whether these will be set by MSVC
+#if HWY_BASELINE_AVX3 != 0 && defined(__AVXVNNI__) && defined(__VAES__) && \
+ defined(__VPCLMULQDQ__) && defined(__AVX512VBMI__) && \
+ defined(__AVX512VBMI2__) && defined(__AVX512VPOPCNTDQ__) && \
+ defined(__AVX512BITALG__)
+#define HWY_BASELINE_AVX3_DL HWY_AVX3_DL
+#else
+#define HWY_BASELINE_AVX3_DL 0
+#endif
+
+#if HWY_ARCH_RVV && defined(__riscv_vector)
+#define HWY_BASELINE_RVV HWY_RVV
+#else
+#define HWY_BASELINE_RVV 0
+#endif
+
+// Allow the user to override this without any guarantee of success.
+#ifndef HWY_BASELINE_TARGETS
+#define HWY_BASELINE_TARGETS \
+ (HWY_BASELINE_SCALAR | HWY_BASELINE_WASM | HWY_BASELINE_PPC8 | \
+ HWY_BASELINE_SVE2 | HWY_BASELINE_SVE | HWY_BASELINE_NEON | \
+ HWY_BASELINE_SSSE3 | HWY_BASELINE_SSE4 | HWY_BASELINE_AVX2 | \
+ HWY_BASELINE_AVX3 | HWY_BASELINE_AVX3_DL | HWY_BASELINE_RVV)
+#endif // HWY_BASELINE_TARGETS
+
+//------------------------------------------------------------------------------
+// Choose target for static dispatch
+
+#define HWY_ENABLED_BASELINE HWY_ENABLED(HWY_BASELINE_TARGETS)
+#if HWY_ENABLED_BASELINE == 0
+#error "At least one baseline target must be defined and enabled"
+#endif
+
+// Best baseline, used for static dispatch. This is the least-significant 1-bit
+// within HWY_ENABLED_BASELINE and lower bit values imply "better".
+#define HWY_STATIC_TARGET (HWY_ENABLED_BASELINE & -HWY_ENABLED_BASELINE)
+
+// Start by assuming static dispatch. If we later use dynamic dispatch, this
+// will be defined to other targets during the multiple-inclusion, and finally
+// return to the initial value. Defining this outside begin/end_target ensures
+// inl headers successfully compile by themselves (required by Bazel).
+#define HWY_TARGET HWY_STATIC_TARGET
+
+//------------------------------------------------------------------------------
+// Choose targets for dynamic dispatch according to one of four policies
+
+#if 1 < (defined(HWY_COMPILE_ONLY_SCALAR) + defined(HWY_COMPILE_ONLY_EMU128) + \
+ defined(HWY_COMPILE_ONLY_STATIC))
+#error "Can only define one of HWY_COMPILE_ONLY_{SCALAR|EMU128|STATIC} - bug?"
+#endif
+// Defining one of HWY_COMPILE_ONLY_* will trump HWY_COMPILE_ALL_ATTAINABLE.
+
+// Clang, GCC and MSVC allow runtime dispatch on x86.
+#if HWY_ARCH_X86
+#define HWY_HAVE_RUNTIME_DISPATCH 1
+// On Arm, currently only GCC does, and we require Linux to detect CPU
+// capabilities.
+#elif HWY_ARCH_ARM && HWY_COMPILER_GCC_ACTUAL && HWY_OS_LINUX
+#define HWY_HAVE_RUNTIME_DISPATCH 1
+#else
+#define HWY_HAVE_RUNTIME_DISPATCH 0
+#endif
+
+// AVX3_DL is not widely available yet. To reduce code size and compile time,
+// only include it in the set of attainable targets (for dynamic dispatch) if
+// the user opts in, OR it is in the baseline (we check whether enabled below).
+#if defined(HWY_WANT_AVX3_DL) || (HWY_BASELINE & HWY_AVX3_DL)
+#define HWY_ATTAINABLE_AVX3_DL HWY_AVX3_DL
+#else
+#define HWY_ATTAINABLE_AVX3_DL 0
+#endif
+
+#if HWY_ARCH_ARM_A64 && (HWY_HAVE_RUNTIME_DISPATCH || \
+ (HWY_ENABLED_BASELINE & (HWY_SVE | HWY_SVE_256)))
+#define HWY_ATTAINABLE_SVE HWY_ENABLED(HWY_SVE | HWY_SVE_256)
+#else
+#define HWY_ATTAINABLE_SVE 0
+#endif
+
+#if HWY_ARCH_ARM_A64 && (HWY_HAVE_RUNTIME_DISPATCH || \
+ (HWY_ENABLED_BASELINE & (HWY_SVE2 | HWY_SVE2_128)))
+#define HWY_ATTAINABLE_SVE2 HWY_ENABLED(HWY_SVE2 | HWY_SVE2_128)
+#else
+#define HWY_ATTAINABLE_SVE2 0
+#endif
+
+// Attainable means enabled and the compiler allows intrinsics (even when not
+// allowed to autovectorize). Used in 3 and 4.
+#if HWY_ARCH_X86
+#define HWY_ATTAINABLE_TARGETS \
+ HWY_ENABLED(HWY_BASELINE_SCALAR | HWY_SSSE3 | HWY_SSE4 | HWY_AVX2 | \
+ HWY_AVX3 | HWY_ATTAINABLE_AVX3_DL)
+#elif HWY_ARCH_ARM && HWY_HAVE_RUNTIME_DISPATCH
+#define HWY_ATTAINABLE_TARGETS \
+ HWY_ENABLED(HWY_BASELINE_SCALAR | HWY_NEON | HWY_ATTAINABLE_SVE | \
+ HWY_ATTAINABLE_SVE2)
+#else
+#define HWY_ATTAINABLE_TARGETS \
+ (HWY_ENABLED_BASELINE | HWY_ATTAINABLE_SVE | HWY_ATTAINABLE_SVE2)
+#endif
+
+// 1) For older compilers: avoid SIMD intrinsics, but still support all ops.
+#if defined(HWY_COMPILE_ONLY_EMU128) && !HWY_BROKEN_EMU128
+#undef HWY_STATIC_TARGET
+#define HWY_STATIC_TARGET HWY_EMU128 // override baseline
+#define HWY_TARGETS HWY_EMU128
+
+// 1b) HWY_SCALAR is less capable than HWY_EMU128 (which supports all ops), but
+// we currently still support it for backwards compatibility.
+#elif defined(HWY_COMPILE_ONLY_SCALAR) || \
+ (defined(HWY_COMPILE_ONLY_EMU128) && HWY_BROKEN_EMU128)
+#undef HWY_STATIC_TARGET
+#define HWY_STATIC_TARGET HWY_SCALAR // override baseline
+#define HWY_TARGETS HWY_SCALAR
+
+// 2) For forcing static dispatch without code changes (removing HWY_EXPORT)
+#elif defined(HWY_COMPILE_ONLY_STATIC)
+#define HWY_TARGETS HWY_STATIC_TARGET
+
+// 3) For tests: include all attainable targets (in particular: scalar)
+#elif defined(HWY_COMPILE_ALL_ATTAINABLE) || defined(HWY_IS_TEST)
+#define HWY_TARGETS HWY_ATTAINABLE_TARGETS
+
+// 4) Default: attainable WITHOUT non-best baseline. This reduces code size by
+// excluding superseded targets, in particular scalar. Note: HWY_STATIC_TARGET
+// may be 2^62 (HWY_SCALAR), so we must not left-shift/add it. Subtracting one
+// sets all lower bits (better targets), then we also include the static target.
+#else
+#define HWY_TARGETS \
+ (HWY_ATTAINABLE_TARGETS & ((HWY_STATIC_TARGET - 1LL) | HWY_STATIC_TARGET))
+
+#endif // target policy
+
+// HWY_ONCE and the multiple-inclusion mechanism rely on HWY_STATIC_TARGET being
+// one of the dynamic targets. This also implies HWY_TARGETS != 0 and
+// (HWY_TARGETS & HWY_ENABLED_BASELINE) != 0.
+#if (HWY_TARGETS & HWY_STATIC_TARGET) == 0
+#error "Logic error: best baseline should be included in dynamic targets"
+#endif
+
+#endif // HIGHWAY_HWY_DETECT_TARGETS_H_