Export of internal Abseil changes
--
1620e8ffaa93ef24510ca60c7fff2a07248ac9f6 by Abseil Team <absl-team@google.com>:
Update comment.
PiperOrigin-RevId: 382858259
--
20db116f28469149d10e0f7f8b976cb903dd4879 by Gennadiy Rozental <rogeeff@google.com>:
Add benchmark running on multiple flags.
Update size_tester to include cost of absl::GetFlag call.
Add size_tester invocation for bool flag.
New benchmark better represent GetFlag usage.
PiperOrigin-RevId: 382820341
--
2e097ad3811c4e329f75b98877a5e74c1d3d84fd by Abseil Team <absl-team@google.com>:
Avoid 64x64->128 multiplication in absl::Hash's mix on AArch64
On AArch64, calculating a 128-bit product is inefficient, because it requires a sequence of two instructions to calculate the upper and lower halves of the result. So calculate a 64-bit product instead.
Making MultType 64-bits means the upper 32 bits of the result do not participate in shift/xor, but the add/multiply gives us sufficient mixing.
PiperOrigin-RevId: 382625931
--
f3ae3f32cb53168c8dc91b766f2932dc87cec503 by Abseil Team <absl-team@google.com>:
Remove homegrown Round implementation
absl/time/duration.cc defined a Round implementation to accommodate old
versions of MSVC that lacked std::round(long double). Abseil no longer
supports those MSVCs, so we don’t need the homegrown implementation
anymore. Remove it, and replace calls to it with std::rint.
PiperOrigin-RevId: 382605191
--
a13631c91bf5478289e1a512ce215c85501a26f7 by Martijn Vels <mvels@google.com>:
Move the Consume() conversion functions out of cord_rep_ring into cord_rep_consume.
This makes these functions generic, so we can repurpose these for the new Btree conversion functions.
PiperOrigin-RevId: 382594902
--
7394c737500c2d8371fcf913b21ad1b321ba499d by Benjamin Barenblat <bbaren@google.com>:
Remove homegrown Round implementation
absl/time/duration.cc defined a Round implementation to accommodate old
versions of MSVC that lacked std::round(long double). Abseil no longer
supports those MSVCs, so we don’t need the homegrown implementation
anymore. Remove it, and replace calls to it with std::rint.
PiperOrigin-RevId: 382569900
--
d72a761f43dc5c9b9510c3a1363177ed26646b5d by Abseil Team <absl-team@google.com>:
Prefer `getentropy` for Emscripten.
It needs a different header, so I've separated it out from the GLIBC
check above.
PiperOrigin-RevId: 382332475
--
74e261dbb467741b2ddd8b490e04c531fdd2f559 by Martijn Vels <mvels@google.com>:
Add BTREE tag for CordRepNode implementing a Btree cord.
This change only forward declared the CordRepBtree class (not implemented yet) and defines the enum value BTREE. While RING and BTREE should never co-exist, we define a new value for BTREE so as not to make transitioning between RING and BTREE harder than it needs to be. This changes shifts the FLAT value / computation from FLAT = 4 to FLAT =5
PiperOrigin-RevId: 382326710
GitOrigin-RevId: 1620e8ffaa93ef24510ca60c7fff2a07248ac9f6
Change-Id: Ia8f99dde3874808f56062bd37ab3e63764099734
diff --git a/CMake/AbseilDll.cmake b/CMake/AbseilDll.cmake
index 8ee4120..78ace82 100644
--- a/CMake/AbseilDll.cmake
+++ b/CMake/AbseilDll.cmake
@@ -203,6 +203,8 @@
"strings/internal/charconv_parse.h"
"strings/internal/cord_internal.cc"
"strings/internal/cord_internal.h"
+ "strings/internal/cord_rep_consume.h"
+ "strings/internal/cord_rep_consume.cc"
"strings/internal/cord_rep_flat.h"
"strings/internal/cord_rep_ring.cc"
"strings/internal/cord_rep_ring.h"
diff --git a/absl/flags/flag_benchmark.cc b/absl/flags/flag_benchmark.cc
index 57584f8..fc572d9 100644
--- a/absl/flags/flag_benchmark.cc
+++ b/absl/flags/flag_benchmark.cc
@@ -101,7 +101,39 @@
A(AbslDuration) \
A(UDT)
-#define FLAG_DEF(T) ABSL_FLAG(T, T##_flag, {}, "");
+#define REPLICATE_0(A, T, name, index) A(T, name, index)
+#define REPLICATE_1(A, T, name, index) \
+ REPLICATE_0(A, T, name, index##0) REPLICATE_0(A, T, name, index##1)
+#define REPLICATE_2(A, T, name, index) \
+ REPLICATE_1(A, T, name, index##0) REPLICATE_1(A, T, name, index##1)
+#define REPLICATE_3(A, T, name, index) \
+ REPLICATE_2(A, T, name, index##0) REPLICATE_2(A, T, name, index##1)
+#define REPLICATE_4(A, T, name, index) \
+ REPLICATE_3(A, T, name, index##0) REPLICATE_3(A, T, name, index##1)
+#define REPLICATE_5(A, T, name, index) \
+ REPLICATE_4(A, T, name, index##0) REPLICATE_4(A, T, name, index##1)
+#define REPLICATE_6(A, T, name, index) \
+ REPLICATE_5(A, T, name, index##0) REPLICATE_5(A, T, name, index##1)
+#define REPLICATE_7(A, T, name, index) \
+ REPLICATE_6(A, T, name, index##0) REPLICATE_6(A, T, name, index##1)
+#define REPLICATE_8(A, T, name, index) \
+ REPLICATE_7(A, T, name, index##0) REPLICATE_7(A, T, name, index##1)
+#define REPLICATE_9(A, T, name, index) \
+ REPLICATE_8(A, T, name, index##0) REPLICATE_8(A, T, name, index##1)
+#if defined(_MSC_VER)
+#define REPLICATE(A, T, name) \
+ REPLICATE_7(A, T, name, 0) REPLICATE_7(A, T, name, 1)
+#define SINGLE_FLAG(T) FLAGS_##T##_flag_00000000
+#else
+#define REPLICATE(A, T, name) \
+ REPLICATE_9(A, T, name, 0) REPLICATE_9(A, T, name, 1)
+#define SINGLE_FLAG(T) FLAGS_##T##_flag_0000000000
+#endif
+#define REPLICATE_ALL(A, T, name) \
+ REPLICATE_9(A, T, name, 0) REPLICATE_9(A, T, name, 1)
+
+#define COUNT(T, name, index) +1
+constexpr size_t kNumFlags = 0 REPLICATE(COUNT, _, _);
#if defined(__clang__) && defined(__linux__)
// Force the flags used for benchmarks into a separate ELF section.
@@ -110,38 +142,87 @@
// benchmark results more reproducible across unrelated code changes.
#pragma clang section data = ".benchmark_flags"
#endif
+#define DEFINE_FLAG(T, name, index) ABSL_FLAG(T, name##_##index, {}, "");
+#define FLAG_DEF(T) REPLICATE(DEFINE_FLAG, T, T##_flag);
BENCHMARKED_TYPES(FLAG_DEF)
#if defined(__clang__) && defined(__linux__)
#pragma clang section data = ""
#endif
// Register thousands of flags to bloat up the size of the registry.
// This mimics real life production binaries.
-#define DEFINE_FLAG_0(name) ABSL_FLAG(int, name, 0, "");
-#define DEFINE_FLAG_1(name) DEFINE_FLAG_0(name##0) DEFINE_FLAG_0(name##1)
-#define DEFINE_FLAG_2(name) DEFINE_FLAG_1(name##0) DEFINE_FLAG_1(name##1)
-#define DEFINE_FLAG_3(name) DEFINE_FLAG_2(name##0) DEFINE_FLAG_2(name##1)
-#define DEFINE_FLAG_4(name) DEFINE_FLAG_3(name##0) DEFINE_FLAG_3(name##1)
-#define DEFINE_FLAG_5(name) DEFINE_FLAG_4(name##0) DEFINE_FLAG_4(name##1)
-#define DEFINE_FLAG_6(name) DEFINE_FLAG_5(name##0) DEFINE_FLAG_5(name##1)
-#define DEFINE_FLAG_7(name) DEFINE_FLAG_6(name##0) DEFINE_FLAG_6(name##1)
-#define DEFINE_FLAG_8(name) DEFINE_FLAG_7(name##0) DEFINE_FLAG_7(name##1)
-#define DEFINE_FLAG_9(name) DEFINE_FLAG_8(name##0) DEFINE_FLAG_8(name##1)
-#define DEFINE_FLAG_10(name) DEFINE_FLAG_9(name##0) DEFINE_FLAG_9(name##1)
-#define DEFINE_FLAG_11(name) DEFINE_FLAG_10(name##0) DEFINE_FLAG_10(name##1)
-#define DEFINE_FLAG_12(name) DEFINE_FLAG_11(name##0) DEFINE_FLAG_11(name##1)
-DEFINE_FLAG_12(bloat_flag_);
+#define BLOAT_FLAG(_unused1, _unused2, index) \
+ ABSL_FLAG(int, bloat_flag_##index, 0, "");
+REPLICATE_ALL(BLOAT_FLAG, _, _)
namespace {
-#define BM_GetFlag(T) \
- void BM_GetFlag_##T(benchmark::State& state) { \
- for (auto _ : state) { \
- benchmark::DoNotOptimize(absl::GetFlag(FLAGS_##T##_flag)); \
- } \
- } \
- BENCHMARK(BM_GetFlag_##T)->ThreadRange(1, 16);
+#define FLAG_PTR(T, name, index) &FLAGS_##name##_##index,
+#define FLAG_PTR_ARR(T) \
+ static constexpr absl::Flag<T>* FlagPtrs_##T[] = { \
+ REPLICATE(FLAG_PTR, T, T##_flag)};
+BENCHMARKED_TYPES(FLAG_PTR_ARR)
-BENCHMARKED_TYPES(BM_GetFlag)
+#define BM_SingleGetFlag(T) \
+ void BM_SingleGetFlag_##T(benchmark::State& state) { \
+ for (auto _ : state) { \
+ benchmark::DoNotOptimize(absl::GetFlag(SINGLE_FLAG(T))); \
+ } \
+ } \
+ BENCHMARK(BM_SingleGetFlag_##T)->ThreadRange(1, 16);
+
+BENCHMARKED_TYPES(BM_SingleGetFlag)
+
+template <typename T>
+struct Accumulator {
+ using type = T;
+};
+template <>
+struct Accumulator<String> {
+ using type = size_t;
+};
+template <>
+struct Accumulator<VectorOfStrings> {
+ using type = size_t;
+};
+template <>
+struct Accumulator<OptionalInt> {
+ using type = bool;
+};
+template <>
+struct Accumulator<OptionalString> {
+ using type = bool;
+};
+template <>
+struct Accumulator<UDT> {
+ using type = bool;
+};
+
+template <typename T>
+void Accumulate(typename Accumulator<T>::type& a, const T& f) {
+ a += f;
+}
+void Accumulate(bool& a, bool f) { a = a || f; }
+void Accumulate(size_t& a, const std::string& f) { a += f.size(); }
+void Accumulate(size_t& a, const std::vector<std::string>& f) { a += f.size(); }
+void Accumulate(bool& a, const OptionalInt& f) { a |= f.has_value(); }
+void Accumulate(bool& a, const OptionalString& f) { a |= f.has_value(); }
+void Accumulate(bool& a, const UDT& f) {
+ a |= reinterpret_cast<int64_t>(&f) & 0x1;
+}
+
+#define BM_ManyGetFlag(T) \
+ void BM_ManyGetFlag_##T(benchmark::State& state) { \
+ Accumulator<T>::type res = {}; \
+ while (state.KeepRunningBatch(kNumFlags)) { \
+ for (auto* flag_ptr : FlagPtrs_##T) { \
+ Accumulate(res, absl::GetFlag(*flag_ptr)); \
+ } \
+ } \
+ benchmark::DoNotOptimize(res); \
+ } \
+ BENCHMARK(BM_ManyGetFlag_##T)->ThreadRange(1, 8);
+
+BENCHMARKED_TYPES(BM_ManyGetFlag)
void BM_ThreadedFindCommandLineFlag(benchmark::State& state) {
char dummy[] = "dummy";
@@ -150,17 +231,18 @@
// is finalized.
absl::ParseCommandLine(1, argv);
- for (auto s : state) {
- benchmark::DoNotOptimize(
- absl::FindCommandLineFlag("bloat_flag_010101010101"));
+ while (state.KeepRunningBatch(kNumFlags)) {
+ for (auto* flag_ptr : FlagPtrs_bool) {
+ benchmark::DoNotOptimize(absl::FindCommandLineFlag(flag_ptr->Name()));
+ }
}
}
BENCHMARK(BM_ThreadedFindCommandLineFlag)->ThreadRange(1, 16);
} // namespace
-#define InvokeGetFlag(T) \
- T AbslInvokeGetFlag##T() { return absl::GetFlag(FLAGS_##T##_flag); } \
+#define InvokeGetFlag(T) \
+ T AbslInvokeGetFlag##T() { return absl::GetFlag(SINGLE_FLAG(T)); } \
int odr##T = (benchmark::DoNotOptimize(AbslInvokeGetFlag##T), 1);
BENCHMARKED_TYPES(InvokeGetFlag)
diff --git a/absl/hash/internal/hash.h b/absl/hash/internal/hash.h
index 69dbbc6..90627e0 100644
--- a/absl/hash/internal/hash.h
+++ b/absl/hash/internal/hash.h
@@ -856,8 +856,15 @@
}
ABSL_ATTRIBUTE_ALWAYS_INLINE static uint64_t Mix(uint64_t state, uint64_t v) {
+#if defined(__aarch64__)
+ // On AArch64, calculating a 128-bit product is inefficient, because it
+ // requires a sequence of two instructions to calculate the upper and lower
+ // halves of the result.
+ using MultType = uint64_t;
+#else
using MultType =
absl::conditional_t<sizeof(size_t) == 4, uint64_t, uint128>;
+#endif
// We do the addition in 64-bit space to make sure the 128-bit
// multiplication is fast. If we were to do it as MultType the compiler has
// to assume that the high word is non-zero and needs to perform 2
diff --git a/absl/random/internal/seed_material.cc b/absl/random/internal/seed_material.cc
index 7c1d9ef..c03cad8 100644
--- a/absl/random/internal/seed_material.cc
+++ b/absl/random/internal/seed_material.cc
@@ -57,6 +57,12 @@
#define ABSL_RANDOM_USE_GET_ENTROPY 1
#endif
+#if defined(__EMSCRIPTEN__)
+#include <sys/random.h>
+// Emscripten has getentropy, but it resides in a different header.
+#define ABSL_RANDOM_USE_GET_ENTROPY 1
+#endif
+
#if defined(ABSL_RANDOM_USE_BCRYPT)
#include <bcrypt.h>
diff --git a/absl/strings/BUILD.bazel b/absl/strings/BUILD.bazel
index 1cb5b3e..b70aac3 100644
--- a/absl/strings/BUILD.bazel
+++ b/absl/strings/BUILD.bazel
@@ -269,10 +269,12 @@
name = "cord_internal",
srcs = [
"internal/cord_internal.cc",
+ "internal/cord_rep_consume.cc",
"internal/cord_rep_ring.cc",
],
hdrs = [
"internal/cord_internal.h",
+ "internal/cord_rep_consume.h",
"internal/cord_rep_flat.h",
"internal/cord_rep_ring.h",
"internal/cord_rep_ring_reader.h",
@@ -292,6 +294,7 @@
"//absl/container:compressed_tuple",
"//absl/container:inlined_vector",
"//absl/container:layout",
+ "//absl/functional:function_ref",
"//absl/meta:type_traits",
],
)
@@ -650,6 +653,22 @@
)
cc_test(
+ name = "cord_rep_consume_test",
+ size = "medium",
+ srcs = ["internal/cord_rep_consume_test.cc"],
+ copts = ABSL_TEST_COPTS,
+ visibility = ["//visibility:private"],
+ deps = [
+ ":cord_internal",
+ ":strings",
+ "//absl/base:config",
+ "//absl/base:core_headers",
+ "//absl/debugging:leak_check",
+ "@com_google_googletest//:gtest_main",
+ ],
+)
+
+cc_test(
name = "cord_ring_test",
size = "medium",
srcs = ["cord_ring_test.cc"],
diff --git a/absl/strings/CMakeLists.txt b/absl/strings/CMakeLists.txt
index 0246dc3..d79ef71 100644
--- a/absl/strings/CMakeLists.txt
+++ b/absl/strings/CMakeLists.txt
@@ -555,11 +555,13 @@
cord_internal
HDRS
"internal/cord_internal.h"
+ "internal/cord_rep_consume.h"
"internal/cord_rep_flat.h"
"internal/cord_rep_ring.h"
"internal/cord_rep_ring_reader.h"
SRCS
"internal/cord_internal.cc"
+ "internal/cord_rep_consume.cc"
"internal/cord_rep_ring.cc"
COPTS
${ABSL_DEFAULT_COPTS}
@@ -904,6 +906,24 @@
absl_cc_test(
NAME
+ cord_rep_consume_test
+ SRCS
+ "internal/cord_rep_consume_test.cc"
+ COPTS
+ ${ABSL_TEST_COPTS}
+ DEPS
+ absl::base
+ absl::config
+ absl::cord_internal
+ absl::core_headers
+ absl::function_ref
+ absl::raw_logging_internal
+ absl::strings
+ GTest::gmock_main
+)
+
+absl_cc_test(
+ NAME
cord_ring_test
SRCS
"cord_ring_test.cc"
diff --git a/absl/strings/internal/cord_internal.h b/absl/strings/internal/cord_internal.h
index 1e2436b..bddc981 100644
--- a/absl/strings/internal/cord_internal.h
+++ b/absl/strings/internal/cord_internal.h
@@ -150,22 +150,24 @@
struct CordRepFlat;
struct CordRepSubstring;
class CordRepRing;
+class CordRepBtree;
// Various representations that we allow
enum CordRepKind {
CONCAT = 0,
SUBSTRING = 1,
- RING = 2,
- EXTERNAL = 3,
+ BTREE = 2,
+ RING = 3,
+ EXTERNAL = 4,
// We have different tags for different sized flat arrays,
- // starting with FLAT, and limited to MAX_FLAT_TAG. The 224 value is based on
+ // starting with FLAT, and limited to MAX_FLAT_TAG. The 225 value is based on
// the current 'size to tag' encoding of 8 / 32 bytes. If a new tag is needed
// in the future, then 'FLAT' and 'MAX_FLAT_TAG' should be adjusted as well
// as the Tag <---> Size logic so that FLAT stil represents the minimum flat
// allocation size. (32 bytes as of now).
- FLAT = 4,
- MAX_FLAT_TAG = 224
+ FLAT = 5,
+ MAX_FLAT_TAG = 225
};
// There are various locations where we want to check if some rep is a 'plain'
@@ -175,8 +177,9 @@
// so likewise align RING to EXTERNAL.
// Note that we can leave this optimization to the compiler. The compiler will
// DTRT when it sees a condition like `tag == EXTERNAL || tag >= FLAT`.
-static_assert(EXTERNAL == RING + 1, "RING and EXTERNAL values not consecutive");
-static_assert(FLAT == EXTERNAL + 1, "EXTERNAL and FLAT values not consecutive");
+static_assert(RING == BTREE + 1, "BTREE and RING not consecutive");
+static_assert(EXTERNAL == RING + 1, "BTREE and EXTERNAL not consecutive");
+static_assert(FLAT == EXTERNAL + 1, "EXTERNAL and FLAT not consecutive");
struct CordRep {
CordRep() = default;
@@ -203,6 +206,9 @@
inline CordRepFlat* flat();
inline const CordRepFlat* flat() const;
+ inline CordRepBtree* btree();
+ inline const CordRepBtree* btree() const;
+
// --------------------------------------------------------------------
// Memory management
diff --git a/absl/strings/internal/cord_rep_consume.cc b/absl/strings/internal/cord_rep_consume.cc
new file mode 100644
index 0000000..8151454
--- /dev/null
+++ b/absl/strings/internal/cord_rep_consume.cc
@@ -0,0 +1,129 @@
+// Copyright 2021 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/strings/internal/cord_rep_consume.h"
+
+#include <array>
+#include <utility>
+
+#include "absl/container/inlined_vector.h"
+#include "absl/functional/function_ref.h"
+#include "absl/strings/internal/cord_internal.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace cord_internal {
+
+namespace {
+
+// Unrefs the provided `substring`, and returns `substring->child`
+// Adds or assumes a reference on `substring->child`
+CordRep* ClipSubstring(CordRepSubstring* substring) {
+ CordRep* child = substring->child;
+ if (substring->refcount.IsOne()) {
+ delete substring;
+ } else {
+ CordRep::Ref(child);
+ CordRep::Unref(substring);
+ }
+ return child;
+}
+
+// Unrefs the provided `concat`, and returns `{concat->left, concat->right}`
+// Adds or assumes a reference on `concat->left` and `concat->right`.
+// Returns an array of 2 elements containing the left and right nodes.
+std::array<CordRep*, 2> ClipConcat(CordRepConcat* concat) {
+ std::array<CordRep*, 2> result{concat->left, concat->right};
+ if (concat->refcount.IsOne()) {
+ delete concat;
+ } else {
+ CordRep::Ref(result[0]);
+ CordRep::Ref(result[1]);
+ CordRep::Unref(concat);
+ }
+ return result;
+}
+
+void Consume(bool forward, CordRep* rep, ConsumeFn consume_fn) {
+ size_t offset = 0;
+ size_t length = rep->length;
+ struct Entry {
+ CordRep* rep;
+ size_t offset;
+ size_t length;
+ };
+ absl::InlinedVector<Entry, 40> stack;
+
+ for (;;) {
+ if (rep->tag == CONCAT) {
+ std::array<CordRep*, 2> res = ClipConcat(rep->concat());
+ CordRep* left = res[0];
+ CordRep* right = res[1];
+
+ if (left->length <= offset) {
+ // Don't need left node
+ offset -= left->length;
+ CordRep::Unref(left);
+ rep = right;
+ continue;
+ }
+
+ size_t length_left = left->length - offset;
+ if (length_left >= length) {
+ // Don't need right node
+ CordRep::Unref(right);
+ rep = left;
+ continue;
+ }
+
+ // Need both nodes
+ size_t length_right = length - length_left;
+ if (forward) {
+ stack.push_back({right, 0, length_right});
+ rep = left;
+ length = length_left;
+ } else {
+ stack.push_back({left, offset, length_left});
+ rep = right;
+ offset = 0;
+ length = length_right;
+ }
+ } else if (rep->tag == SUBSTRING) {
+ offset += rep->substring()->start;
+ rep = ClipSubstring(rep->substring());
+ } else {
+ consume_fn(rep, offset, length);
+ if (stack.empty()) return;
+
+ rep = stack.back().rep;
+ offset = stack.back().offset;
+ length = stack.back().length;
+ stack.pop_back();
+ }
+ }
+}
+
+} // namespace
+
+void Consume(CordRep* rep, ConsumeFn consume_fn) {
+ return Consume(true, rep, std::move(consume_fn));
+}
+
+void ReverseConsume(CordRep* rep, ConsumeFn consume_fn) {
+ return Consume(false, rep, std::move(consume_fn));
+}
+
+} // namespace cord_internal
+ABSL_NAMESPACE_END
+} // namespace absl
diff --git a/absl/strings/internal/cord_rep_consume.h b/absl/strings/internal/cord_rep_consume.h
new file mode 100644
index 0000000..d46fca2
--- /dev/null
+++ b/absl/strings/internal/cord_rep_consume.h
@@ -0,0 +1,50 @@
+// Copyright 2021 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.
+
+#ifndef ABSL_STRINGS_INTERNAL_CORD_REP_CONSUME_H_
+#define ABSL_STRINGS_INTERNAL_CORD_REP_CONSUME_H_
+
+#include <functional>
+
+#include "absl/functional/function_ref.h"
+#include "absl/strings/internal/cord_internal.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace cord_internal {
+
+// Functor for the Consume() and ReverseConsume() functions:
+// void ConsumeFunc(CordRep* rep, size_t offset, size_t length);
+// See the Consume() and ReverseConsume() function comments for documentation.
+using ConsumeFn = FunctionRef<void(CordRep*, size_t, size_t)>;
+
+// Consume() and ReverseConsume() consume CONCAT based trees and invoke the
+// provided functor with the contained nodes in the proper forward or reverse
+// order, which is used to convert CONCAT trees into other tree or cord data.
+// All CONCAT and SUBSTRING nodes are processed internally. The 'offset`
+// parameter of the functor is non-zero for any nodes below SUBSTRING nodes.
+// It's up to the caller to form these back into SUBSTRING nodes or otherwise
+// store offset / prefix information. These functions are intended to be used
+// only for migration / transitional code where due to factors such as ODR
+// violations, we can not 100% guarantee that all code respects 'new format'
+// settings and flags, so we need to be able to parse old data on the fly until
+// all old code is deprecated / no longer the default format.
+void Consume(CordRep* rep, ConsumeFn consume_fn);
+void ReverseConsume(CordRep* rep, ConsumeFn consume_fn);
+
+} // namespace cord_internal
+ABSL_NAMESPACE_END
+} // namespace absl
+
+#endif // ABSL_STRINGS_INTERNAL_CORD_REP_CONSUME_H_
diff --git a/absl/strings/internal/cord_rep_consume_test.cc b/absl/strings/internal/cord_rep_consume_test.cc
new file mode 100644
index 0000000..e507824
--- /dev/null
+++ b/absl/strings/internal/cord_rep_consume_test.cc
@@ -0,0 +1,173 @@
+// Copyright 2021 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/strings/internal/cord_rep_consume.h"
+
+#include <functional>
+#include <utility>
+
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+#include "absl/strings/internal/cord_internal.h"
+#include "absl/strings/internal/cord_rep_flat.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace cord_internal {
+namespace {
+
+using testing::InSequence;
+using testing::MockFunction;
+
+// Returns the depth of a node
+int Depth(const CordRep* rep) {
+ return (rep->tag == CONCAT) ? rep->concat()->depth() : 0;
+}
+
+// Creates a concatenation of the specified nodes.
+CordRepConcat* CreateConcat(CordRep* left, CordRep* right) {
+ auto* concat = new CordRepConcat();
+ concat->tag = CONCAT;
+ concat->left = left;
+ concat->right = right;
+ concat->length = left->length + right->length;
+ concat->set_depth(1 + (std::max)(Depth(left), Depth(right)));
+ return concat;
+}
+
+// Creates a flat with the length set to `length`
+CordRepFlat* CreateFlatWithLength(size_t length) {
+ auto* flat = CordRepFlat::New(length);
+ flat->length = length;
+ return flat;
+}
+
+// Creates a substring node on the specified child.
+CordRepSubstring* CreateSubstring(CordRep* child, size_t start, size_t length) {
+ auto* rep = new CordRepSubstring();
+ rep->length = length;
+ rep->tag = SUBSTRING;
+ rep->start = start;
+ rep->child = child;
+ return rep;
+}
+
+// Flats we use in the tests
+CordRep* flat[6];
+
+// Creates a test tree
+CordRep* CreateTestTree() {
+ flat[0] = CreateFlatWithLength(1);
+ flat[1] = CreateFlatWithLength(7);
+ CordRepConcat* left = CreateConcat(flat[0], CreateSubstring(flat[1], 2, 4));
+
+ flat[2] = CreateFlatWithLength(9);
+ flat[3] = CreateFlatWithLength(13);
+ CordRepConcat* right1 = CreateConcat(flat[2], flat[3]);
+
+ flat[4] = CreateFlatWithLength(15);
+ flat[5] = CreateFlatWithLength(19);
+ CordRepConcat* right2 = CreateConcat(flat[4], flat[5]);
+
+ CordRepConcat* right = CreateConcat(right1, CreateSubstring(right2, 5, 17));
+ return CreateConcat(left, right);
+}
+
+TEST(CordRepConsumeTest, Consume) {
+ InSequence in_sequence;
+ CordRep* tree = CreateTestTree();
+ MockFunction<void(CordRep*, size_t, size_t)> consume;
+ EXPECT_CALL(consume, Call(flat[0], 0, 1));
+ EXPECT_CALL(consume, Call(flat[1], 2, 4));
+ EXPECT_CALL(consume, Call(flat[2], 0, 9));
+ EXPECT_CALL(consume, Call(flat[3], 0, 13));
+ EXPECT_CALL(consume, Call(flat[4], 5, 10));
+ EXPECT_CALL(consume, Call(flat[5], 0, 7));
+ Consume(tree, consume.AsStdFunction());
+ for (CordRep* rep : flat) {
+ EXPECT_TRUE(rep->refcount.IsOne());
+ CordRep::Unref(rep);
+ }
+}
+
+TEST(CordRepConsumeTest, ConsumeShared) {
+ InSequence in_sequence;
+ CordRep* tree = CreateTestTree();
+ MockFunction<void(CordRep*, size_t, size_t)> consume;
+ EXPECT_CALL(consume, Call(flat[0], 0, 1));
+ EXPECT_CALL(consume, Call(flat[1], 2, 4));
+ EXPECT_CALL(consume, Call(flat[2], 0, 9));
+ EXPECT_CALL(consume, Call(flat[3], 0, 13));
+ EXPECT_CALL(consume, Call(flat[4], 5, 10));
+ EXPECT_CALL(consume, Call(flat[5], 0, 7));
+ Consume(CordRep::Ref(tree), consume.AsStdFunction());
+ for (CordRep* rep : flat) {
+ EXPECT_FALSE(rep->refcount.IsOne());
+ CordRep::Unref(rep);
+ }
+ CordRep::Unref(tree);
+}
+
+TEST(CordRepConsumeTest, Reverse) {
+ InSequence in_sequence;
+ CordRep* tree = CreateTestTree();
+ MockFunction<void(CordRep*, size_t, size_t)> consume;
+ EXPECT_CALL(consume, Call(flat[5], 0, 7));
+ EXPECT_CALL(consume, Call(flat[4], 5, 10));
+ EXPECT_CALL(consume, Call(flat[3], 0, 13));
+ EXPECT_CALL(consume, Call(flat[2], 0, 9));
+ EXPECT_CALL(consume, Call(flat[1], 2, 4));
+ EXPECT_CALL(consume, Call(flat[0], 0, 1));
+ ReverseConsume(tree, consume.AsStdFunction());
+ for (CordRep* rep : flat) {
+ EXPECT_TRUE(rep->refcount.IsOne());
+ CordRep::Unref(rep);
+ }
+}
+
+TEST(CordRepConsumeTest, ReverseShared) {
+ InSequence in_sequence;
+ CordRep* tree = CreateTestTree();
+ MockFunction<void(CordRep*, size_t, size_t)> consume;
+ EXPECT_CALL(consume, Call(flat[5], 0, 7));
+ EXPECT_CALL(consume, Call(flat[4], 5, 10));
+ EXPECT_CALL(consume, Call(flat[3], 0, 13));
+ EXPECT_CALL(consume, Call(flat[2], 0, 9));
+ EXPECT_CALL(consume, Call(flat[1], 2, 4));
+ EXPECT_CALL(consume, Call(flat[0], 0, 1));
+ ReverseConsume(CordRep::Ref(tree), consume.AsStdFunction());
+ for (CordRep* rep : flat) {
+ EXPECT_FALSE(rep->refcount.IsOne());
+ CordRep::Unref(rep);
+ }
+ CordRep::Unref(tree);
+}
+
+TEST(CordRepConsumeTest, UnreachableFlat) {
+ InSequence in_sequence;
+ CordRepFlat* flat1 = CreateFlatWithLength(10);
+ CordRepFlat* flat2 = CreateFlatWithLength(20);
+ CordRepConcat* concat = CreateConcat(flat1, flat2);
+ CordRepSubstring* tree = CreateSubstring(concat, 15, 10);
+ MockFunction<void(CordRep*, size_t, size_t)> consume;
+ EXPECT_CALL(consume, Call(flat2, 5, 10));
+ Consume(tree, consume.AsStdFunction());
+ EXPECT_TRUE(flat2->refcount.IsOne());
+ CordRep::Unref(flat2);
+}
+
+} // namespace
+} // namespace cord_internal
+ABSL_NAMESPACE_END
+} // namespace absl
diff --git a/absl/strings/internal/cord_rep_flat.h b/absl/strings/internal/cord_rep_flat.h
index a98aa9d..cddb282 100644
--- a/absl/strings/internal/cord_rep_flat.h
+++ b/absl/strings/internal/cord_rep_flat.h
@@ -44,11 +44,11 @@
static constexpr size_t kMinFlatLength = kMinFlatSize - kFlatOverhead;
constexpr uint8_t AllocatedSizeToTagUnchecked(size_t size) {
- return static_cast<uint8_t>((size <= 1024) ? size / 8
- : 128 + size / 32 - 1024 / 32);
+ return static_cast<uint8_t>((size <= 1024) ? size / 8 + 1
+ : 129 + size / 32 - 1024 / 32);
}
-static_assert(kMinFlatSize / 8 >= FLAT, "");
+static_assert(kMinFlatSize / 8 + 1 >= FLAT, "");
static_assert(AllocatedSizeToTagUnchecked(kMaxFlatSize) <= MAX_FLAT_TAG, "");
// Helper functions for rounded div, and rounding to exact sizes.
@@ -73,7 +73,7 @@
// Converts the provided tag to the corresponding allocated size
constexpr size_t TagToAllocatedSize(uint8_t tag) {
- return (tag <= 128) ? (tag * 8) : (1024 + (tag - 128) * 32);
+ return (tag <= 129) ? ((tag - 1) * 8) : (1024 + (tag - 129) * 32);
}
// Converts the provided tag to the corresponding available data length
@@ -82,7 +82,7 @@
}
// Enforce that kMaxFlatSize maps to a well-known exact tag value.
-static_assert(TagToAllocatedSize(224) == kMaxFlatSize, "Bad tag logic");
+static_assert(TagToAllocatedSize(225) == kMaxFlatSize, "Bad tag logic");
struct CordRepFlat : public CordRep {
// Creates a new flat node.
diff --git a/absl/strings/internal/cord_rep_ring.cc b/absl/strings/internal/cord_rep_ring.cc
index f78c94e..20a6fc2 100644
--- a/absl/strings/internal/cord_rep_ring.cc
+++ b/absl/strings/internal/cord_rep_ring.cc
@@ -26,6 +26,7 @@
#include "absl/base/macros.h"
#include "absl/container/inlined_vector.h"
#include "absl/strings/internal/cord_internal.h"
+#include "absl/strings/internal/cord_rep_consume.h"
#include "absl/strings/internal/cord_rep_flat.h"
namespace absl {
@@ -49,14 +50,6 @@
}
}
-// Removes a reference from `rep` only.
-// Asserts that the refcount after decrement is not zero.
-inline bool UnrefNeverOne(CordRep* rep) {
- bool result = rep->refcount.Decrement();
- assert(result);
- return result;
-}
-
// Creates a flat from the provided string data, allocating up to `extra`
// capacity in the returned flat depending on kMaxFlatLength limitations.
// Requires `len` to be less or equal to `kMaxFlatLength`
@@ -68,40 +61,6 @@
return rep;
}
-// Unrefs the provided `substring`, and returns `substring->child`
-// Adds or assumes a reference on `substring->child`
-CordRep* ClipSubstring(CordRepSubstring* substring) {
- CordRep* child = substring->child;
- if (substring->refcount.IsOne()) {
- delete substring;
- } else {
- CordRep::Ref(child);
- if (ABSL_PREDICT_FALSE(!substring->refcount.Decrement())) {
- UnrefNeverOne(child);
- delete substring;
- }
- }
- return child;
-}
-
-// Unrefs the provided `concat`, and returns `{concat->left, concat->right}`
-// Adds or assumes a reference on `concat->left` and `concat->right`.
-std::pair<CordRep*, CordRep*> ClipConcat(CordRepConcat* concat) {
- auto result = std::make_pair(concat->left, concat->right);
- if (concat->refcount.IsOne()) {
- delete concat;
- } else {
- CordRep::Ref(result.first);
- CordRep::Ref(result.second);
- if (ABSL_PREDICT_FALSE(!concat->refcount.Decrement())) {
- UnrefNeverOne(result.first);
- UnrefNeverOne(result.second);
- delete concat;
- }
- }
- return result;
-}
-
// Unrefs the entries in `[head, tail)`.
// Requires all entries to be a FLAT or EXTERNAL node.
void UnrefEntries(const CordRepRing* rep, index_type head, index_type tail) {
@@ -117,79 +76,6 @@
});
}
-template <typename F>
-void Consume(Direction direction, CordRep* rep, F&& fn) {
- size_t offset = 0;
- size_t length = rep->length;
- struct Entry {
- CordRep* rep;
- size_t offset;
- size_t length;
- };
- absl::InlinedVector<Entry, 40> stack;
-
- for (;;) {
- if (rep->tag >= FLAT || rep->tag == EXTERNAL || rep->tag == RING) {
- fn(rep, offset, length);
- if (stack.empty()) return;
-
- rep = stack.back().rep;
- offset = stack.back().offset;
- length = stack.back().length;
- stack.pop_back();
- } else if (rep->tag == SUBSTRING) {
- offset += rep->substring()->start;
- rep = ClipSubstring(rep->substring());
- } else if (rep->tag == CONCAT) {
- auto res = ClipConcat(rep->concat());
- CordRep* left = res.first;
- CordRep* right = res.second;
-
- if (left->length <= offset) {
- // Don't need left node
- offset -= left->length;
- CordRep::Unref(left);
- rep = right;
- continue;
- }
-
- size_t length_left = left->length - offset;
- if (length_left >= length) {
- // Don't need right node
- CordRep::Unref(right);
- rep = left;
- continue;
- }
-
- // Need both nodes
- size_t length_right = length - length_left;
- if (direction == Direction::kReversed) {
- stack.push_back({left, offset, length_left});
- rep = right;
- offset = 0;
- length = length_right;
- } else {
- stack.push_back({right, 0, length_right});
- rep = left;
- length = length_left;
- }
- } else {
- assert("Valid tag" == nullptr);
- return;
- }
- }
-}
-
-template <typename F>
-void Consume(CordRep* rep, F&& fn) {
- return Consume(Direction::kForward, rep, std::forward<F>(fn));
-}
-
-template <typename F>
-void RConsume(CordRep* rep, F&& fn) {
- return Consume(Direction::kReversed, rep, std::forward<F>(fn));
-}
-
} // namespace
std::ostream& operator<<(std::ostream& s, const CordRepRing& rep) {
@@ -581,7 +467,7 @@
}
CordRepRing* CordRepRing::PrependSlow(CordRepRing* rep, CordRep* child) {
- RConsume(child, [&](CordRep* child_arg, size_t offset, size_t len) {
+ ReverseConsume(child, [&](CordRep* child_arg, size_t offset, size_t len) {
if (IsFlatOrExternal(child_arg)) {
rep = PrependLeaf(rep, child_arg, offset, len);
} else {
diff --git a/absl/strings/internal/str_split_internal.h b/absl/strings/internal/str_split_internal.h
index 17c1bfe..e766421 100644
--- a/absl/strings/internal/str_split_internal.h
+++ b/absl/strings/internal/str_split_internal.h
@@ -64,7 +64,7 @@
ConvertibleToStringView(const std::string& s) // NOLINT(runtime/explicit)
: value_(s) {}
- // Matches rvalue strings and moves their data to a member.
+ // Disable conversion from rvalue strings.
ConvertibleToStringView(std::string&& s) = delete;
ConvertibleToStringView(const std::string&& s) = delete;
