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Commit 6bda8181 by Derek Mauro Committed by Copybara-Service
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Delete //absl/base/internal/prefetch.h 

Public functions are now available in //absl/base/prefetch.h

PiperOrigin-RevId: 561649346
Change-Id: Ic377ad5f21c9a44ea1f213dec17f5cf97795ebde
parent a86bb8a9
Showing with 2 additions and 187 deletions
CMake/AbseilDll.cmake
...@@ -28,7 +28,6 @@ set(ABSL_INTERNAL_DLL_FILES ...@@ -28,7 +28,6 @@ set(ABSL_INTERNAL_DLL_FILES
"base/internal/low_level_scheduling.h" "base/internal/low_level_scheduling.h"
"base/internal/nullability_impl.h" "base/internal/nullability_impl.h"
"base/internal/per_thread_tls.h" "base/internal/per_thread_tls.h"
"base/internal/prefetch.h"
"base/prefetch.h" "base/prefetch.h"
"base/internal/pretty_function.h" "base/internal/pretty_function.h"
"base/internal/raw_logging.cc" "base/internal/raw_logging.cc"
......
absl/base/BUILD.bazel
...@@ -758,14 +758,13 @@ cc_test( ...@@ -758,14 +758,13 @@ cc_test(
cc_library( cc_library(
name = "prefetch", name = "prefetch",
hdrs = [ hdrs = [
"internal/prefetch.h",
"prefetch.h", "prefetch.h",
], ],
copts = ABSL_DEFAULT_COPTS, copts = ABSL_DEFAULT_COPTS,
linkopts = ABSL_DEFAULT_LINKOPTS, linkopts = ABSL_DEFAULT_LINKOPTS,
deps = [ deps = [
":config", ":config",
":core_headers", # TODO(b/265984188): remove ":core_headers",
], ],
) )
...@@ -773,7 +772,6 @@ cc_test( ...@@ -773,7 +772,6 @@ cc_test(
name = "prefetch_test", name = "prefetch_test",
size = "small", size = "small",
srcs = [ srcs = [
"internal/prefetch_test.cc",
"prefetch_test.cc", "prefetch_test.cc",
], ],
copts = ABSL_TEST_COPTS, copts = ABSL_TEST_COPTS,
......
absl/base/CMakeLists.txt
...@@ -677,14 +677,13 @@ absl_cc_library( ...@@ -677,14 +677,13 @@ absl_cc_library(
prefetch prefetch
HDRS HDRS
"prefetch.h" "prefetch.h"
"internal/prefetch.h"
COPTS COPTS
${ABSL_DEFAULT_COPTS} ${ABSL_DEFAULT_COPTS}
LINKOPTS LINKOPTS
${ABSL_DEFAULT_LINKOPTS} ${ABSL_DEFAULT_LINKOPTS}
DEPS DEPS
absl::config absl::config
absl::core_headers # TODO(b/265984188): remove absl::core_headers
) )
absl_cc_test( absl_cc_test(
...@@ -692,7 +691,6 @@ absl_cc_test( ...@@ -692,7 +691,6 @@ absl_cc_test(
prefetch_test prefetch_test
SRCS SRCS
"prefetch_test.cc" "prefetch_test.cc"
"internal/prefetch_test.cc"
COPTS COPTS
${ABSL_TEST_COPTS} ${ABSL_TEST_COPTS}
DEPS DEPS
......
absl/base/internal/prefetch.h deleted 100644 → 0
// Copyright 2022 The Abseil Authors.
//
// 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.
// TODO(b/265984188): remove all uses and delete this header.
#ifndef ABSL_BASE_INTERNAL_PREFETCH_H_
#define ABSL_BASE_INTERNAL_PREFETCH_H_
#include "absl/base/attributes.h"
#include "absl/base/config.h"
#include "absl/base/prefetch.h"
#ifdef __SSE__
#include <xmmintrin.h>
#endif
#if defined(_MSC_VER) && defined(ABSL_INTERNAL_HAVE_SSE)
#include <intrin.h>
#pragma intrinsic(_mm_prefetch)
#endif
// Compatibility wrappers around __builtin_prefetch, to prefetch data
// for read if supported by the toolchain.
// Move data into the cache before it is read, or "prefetch" it.
//
// The value of `addr` is the address of the memory to prefetch. If
// the target and compiler support it, data prefetch instructions are
// generated. If the prefetch is done some time before the memory is
// read, it may be in the cache by the time the read occurs.
//
// The function names specify the temporal locality heuristic applied,
// using the names of Intel prefetch instructions:
//
// T0 - high degree of temporal locality; data should be left in as
// many levels of the cache possible
// T1 - moderate degree of temporal locality
// T2 - low degree of temporal locality
// Nta - no temporal locality, data need not be left in the cache
// after the read
//
// Incorrect or gratuitous use of these functions can degrade
// performance, so use them only when representative benchmarks show
// an improvement.
//
// Example usage:
//
// absl::base_internal::PrefetchT0(addr);
//
// Currently, the different prefetch calls behave on some Intel
// architectures as follows:
//
// SNB..SKL SKX
// PrefetchT0() L1/L2/L3 L1/L2
// PrefetchT1() L2/L3 L2
// PrefetchT2() L2/L3 L2
// PrefetchNta() L1/--/L3 L1*
//
// * On SKX PrefetchNta() will bring the line into L1 but will evict
// from L3 cache. This might result in surprising behavior.
//
// SNB = Sandy Bridge, SKL = Skylake, SKX = Skylake Xeon.
//
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
ABSL_DEPRECATED("Use absl::PrefetchToLocalCache() instead")
inline void PrefetchT0(const void* address) {
absl::PrefetchToLocalCache(address);
}
ABSL_DEPRECATED("Use absl::PrefetchToLocalCache() instead")
inline void PrefetchNta(const void* address) {
absl::PrefetchToLocalCacheNta(address);
}
ABSL_DEPRECATED("Use __builtin_prefetch() for advanced prefetch logic instead")
void PrefetchT1(const void* addr);
ABSL_DEPRECATED("Use __builtin_prefetch() for advanced prefetch logic instead")
void PrefetchT2(const void* addr);
// Implementation details follow.
#if ABSL_HAVE_BUILTIN(__builtin_prefetch) || defined(__GNUC__)
#define ABSL_INTERNAL_HAVE_PREFETCH 1
// See __builtin_prefetch:
// https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html.
//
// These functions speculatively load for read only. This is
// safe for all currently supported platforms. However, prefetch for
// store may have problems depending on the target platform.
//
inline void PrefetchT1(const void* addr) {
// Note: this uses prefetcht1 on Intel.
__builtin_prefetch(addr, 0, 2);
}
inline void PrefetchT2(const void* addr) {
// Note: this uses prefetcht2 on Intel.
__builtin_prefetch(addr, 0, 1);
}
#elif defined(ABSL_INTERNAL_HAVE_SSE)
#define ABSL_INTERNAL_HAVE_PREFETCH 1
inline void PrefetchT1(const void* addr) {
_mm_prefetch(reinterpret_cast<const char*>(addr), _MM_HINT_T1);
}
inline void PrefetchT2(const void* addr) {
_mm_prefetch(reinterpret_cast<const char*>(addr), _MM_HINT_T2);
}
#else
inline void PrefetchT1(const void*) {}
inline void PrefetchT2(const void*) {}
#endif
} // namespace base_internal
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_INTERNAL_PREFETCH_H_
absl/base/internal/prefetch_test.cc deleted 100644 → 0
// Copyright 2022 The Abseil Authors.
//
// 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.
#include "absl/base/internal/prefetch.h"
#include "gtest/gtest.h"
namespace {
int number = 42;
TEST(Prefetch, TemporalLocalityNone) {
absl::base_internal::PrefetchNta(&number);
EXPECT_EQ(number, 42);
}
TEST(Prefetch, TemporalLocalityLow) {
absl::base_internal::PrefetchT2(&number);
EXPECT_EQ(number, 42);
}
TEST(Prefetch, TemporalLocalityMedium) {
absl::base_internal::PrefetchT1(&number);
EXPECT_EQ(number, 42);
}
TEST(Prefetch, TemporalLocalityHigh) {
absl::base_internal::PrefetchT0(&number);
EXPECT_EQ(number, 42);
}
} // namespace
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