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-rw-r--r--absl/base/BUILD.bazel5
-rw-r--r--absl/base/CMakeLists.txt1
-rw-r--r--absl/base/internal/atomic_hook.h39
-rw-r--r--absl/base/internal/atomic_hook_test.cc9
-rw-r--r--absl/base/internal/atomic_hook_test_helper.cc3
-rw-r--r--absl/base/internal/raw_logging.cc12
-rw-r--r--absl/base/internal/raw_logging.h3
-rw-r--r--absl/base/internal/spinlock.cc4
-rw-r--r--absl/container/internal/btree.h346
-rw-r--r--absl/flags/flag.h33
-rw-r--r--absl/flags/internal/flag.h28
-rw-r--r--absl/random/distributions.h8
-rw-r--r--absl/strings/charconv.cc1
-rw-r--r--absl/strings/string_view_benchmark.cc34
-rw-r--r--absl/synchronization/mutex.cc17
15 files changed, 315 insertions, 228 deletions
diff --git a/absl/base/BUILD.bazel b/absl/base/BUILD.bazel
index e2068f51..9814e420 100644
--- a/absl/base/BUILD.bazel
+++ b/absl/base/BUILD.bazel
@@ -34,7 +34,10 @@ cc_library(
visibility = [
"//absl:__subpackages__",
],
- deps = [":config"],
+ deps = [
+ ":config",
+ ":core_headers",
+ ],
)
cc_library(
diff --git a/absl/base/CMakeLists.txt b/absl/base/CMakeLists.txt
index 60fc1a83..3ca985a9 100644
--- a/absl/base/CMakeLists.txt
+++ b/absl/base/CMakeLists.txt
@@ -23,6 +23,7 @@ absl_cc_library(
"internal/atomic_hook.h"
DEPS
absl::config
+ absl::core_headers
COPTS
${ABSL_DEFAULT_COPTS}
)
diff --git a/absl/base/internal/atomic_hook.h b/absl/base/internal/atomic_hook.h
index d885bc05..ae21cd7f 100644
--- a/absl/base/internal/atomic_hook.h
+++ b/absl/base/internal/atomic_hook.h
@@ -20,16 +20,21 @@
#include <cstdint>
#include <utility>
+#include "absl/base/attributes.h"
#include "absl/base/config.h"
-#ifdef _MSC_FULL_VER
-#define ABSL_HAVE_WORKING_ATOMIC_POINTER 0
+#if defined(_MSC_VER) && !defined(__clang__)
#define ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT 0
#else
-#define ABSL_HAVE_WORKING_ATOMIC_POINTER 1
#define ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT 1
#endif
+#if defined(_MSC_VER)
+#define ABSL_HAVE_WORKING_ATOMIC_POINTER 0
+#else
+#define ABSL_HAVE_WORKING_ATOMIC_POINTER 1
+#endif
+
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
@@ -37,6 +42,15 @@ namespace base_internal {
template <typename T>
class AtomicHook;
+// To workaround AtomicHook not being constant-initializable on some platforms,
+// prefer to annotate instances with `ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES`
+// instead of `ABSL_CONST_INIT`.
+#if ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT
+#define ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES ABSL_CONST_INIT
+#else
+#define ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES
+#endif
+
// `AtomicHook` is a helper class, templatized on a raw function pointer type,
// for implementing Abseil customization hooks. It is a callable object that
// dispatches to the registered hook. Objects of type `AtomicHook` must have
@@ -45,8 +59,11 @@ class AtomicHook;
// A default constructed object performs a no-op (and returns a default
// constructed object) if no hook has been registered.
//
-// Hooks can be pre-registered via constant initialization, for example,
-// `ABSL_CONST_INIT static AtomicHook<void(*)()> my_hook(DefaultAction);`
+// Hooks can be pre-registered via constant initialization, for example:
+//
+// ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES static AtomicHook<void(*)()>
+// my_hook(DefaultAction);
+//
// and then changed at runtime via a call to `Store()`.
//
// Reads and writes guarantee memory_order_acquire/memory_order_release
@@ -65,11 +82,15 @@ class AtomicHook<ReturnType (*)(Args...)> {
#if ABSL_HAVE_WORKING_ATOMIC_POINTER && ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT
explicit constexpr AtomicHook(FnPtr default_fn)
: hook_(default_fn), default_fn_(default_fn) {}
+#elif ABSL_HAVE_WORKING_CONSTEXPR_STATIC_INIT
+ explicit constexpr AtomicHook(FnPtr default_fn)
+ : hook_(kUninitialized), default_fn_(default_fn) {}
#else
- // On MSVC, this function sometimes executes after dynamic initialization =(.
- // If a non-zero `hook_` has been installed by a dynamic initializer, we want
- // to preserve it. If not, `hook_` will be zero initialized and we have no
- // need to set it to `kUninitialized`.
+ // As of January 2020, on all known versions of MSVC this constructor runs in
+ // the global constructor sequence. If `Store()` is called by a dynamic
+ // initializer, we want to preserve the value, even if this constructor runs
+ // after the call to `Store()`. If not, `hook_` will be
+ // zero-initialized by the linker and we have no need to set it.
// https://developercommunity.visualstudio.com/content/problem/336946/class-with-constexpr-constructor-not-using-static.html
explicit constexpr AtomicHook(FnPtr default_fn)
: /* hook_(deliberately omitted), */ default_fn_(default_fn) {
diff --git a/absl/base/internal/atomic_hook_test.cc b/absl/base/internal/atomic_hook_test.cc
index 794072ee..e577a8fd 100644
--- a/absl/base/internal/atomic_hook_test.cc
+++ b/absl/base/internal/atomic_hook_test.cc
@@ -27,7 +27,9 @@ int value = 0;
void TestHook(int x) { value = x; }
TEST(AtomicHookTest, NoDefaultFunction) {
- ABSL_CONST_INIT static absl::base_internal::AtomicHook<void(*)(int)> hook;
+ ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES static absl::base_internal::AtomicHook<
+ void (*)(int)>
+ hook;
value = 0;
// Test the default DummyFunction.
@@ -53,8 +55,9 @@ TEST(AtomicHookTest, NoDefaultFunction) {
TEST(AtomicHookTest, WithDefaultFunction) {
// Set the default value to TestHook at compile-time.
- ABSL_CONST_INIT static absl::base_internal::AtomicHook<void (*)(int)> hook(
- TestHook);
+ ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES static absl::base_internal::AtomicHook<
+ void (*)(int)>
+ hook(TestHook);
value = 0;
// Test the default value is TestHook.
diff --git a/absl/base/internal/atomic_hook_test_helper.cc b/absl/base/internal/atomic_hook_test_helper.cc
index f95d962b..537d47cd 100644
--- a/absl/base/internal/atomic_hook_test_helper.cc
+++ b/absl/base/internal/atomic_hook_test_helper.cc
@@ -21,7 +21,8 @@ namespace absl {
ABSL_NAMESPACE_BEGIN
namespace atomic_hook_internal {
-ABSL_CONST_INIT absl::base_internal::AtomicHook<VoidF> func(DefaultFunc);
+ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES absl::base_internal::AtomicHook<VoidF>
+ func(DefaultFunc);
ABSL_CONST_INIT int default_func_calls = 0;
void DefaultFunc() { default_func_calls++; }
void RegisterFunc(VoidF f) { func.Store(f); }
diff --git a/absl/base/internal/raw_logging.cc b/absl/base/internal/raw_logging.cc
index e36eb29a..40cea550 100644
--- a/absl/base/internal/raw_logging.cc
+++ b/absl/base/internal/raw_logging.cc
@@ -71,10 +71,12 @@
// Explicitly #error out when not ABSL_LOW_LEVEL_WRITE_SUPPORTED, except for a
// whitelisted set of platforms for which we expect not to be able to raw log.
-ABSL_CONST_INIT static absl::base_internal::AtomicHook<
- absl::raw_logging_internal::LogPrefixHook> log_prefix_hook;
-ABSL_CONST_INIT static absl::base_internal::AtomicHook<
- absl::raw_logging_internal::AbortHook> abort_hook;
+ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES static absl::base_internal::AtomicHook<
+ absl::raw_logging_internal::LogPrefixHook>
+ log_prefix_hook;
+ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES static absl::base_internal::AtomicHook<
+ absl::raw_logging_internal::AbortHook>
+ abort_hook;
#ifdef ABSL_LOW_LEVEL_WRITE_SUPPORTED
static const char kTruncated[] = " ... (message truncated)\n";
@@ -225,7 +227,7 @@ bool RawLoggingFullySupported() {
#endif // !ABSL_LOW_LEVEL_WRITE_SUPPORTED
}
-ABSL_CONST_INIT ABSL_DLL
+ABSL_DLL ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES
absl::base_internal::AtomicHook<InternalLogFunction>
internal_log_function(DefaultInternalLog);
diff --git a/absl/base/internal/raw_logging.h b/absl/base/internal/raw_logging.h
index ac74f97d..418d6c85 100644
--- a/absl/base/internal/raw_logging.h
+++ b/absl/base/internal/raw_logging.h
@@ -170,7 +170,8 @@ using InternalLogFunction = void (*)(absl::LogSeverity severity,
const char* file, int line,
const std::string& message);
-ABSL_DLL extern base_internal::AtomicHook<InternalLogFunction>
+ABSL_DLL ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES extern base_internal::AtomicHook<
+ InternalLogFunction>
internal_log_function;
void RegisterInternalLogFunction(InternalLogFunction func);
diff --git a/absl/base/internal/spinlock.cc b/absl/base/internal/spinlock.cc
index 8dd8dab9..830d4729 100644
--- a/absl/base/internal/spinlock.cc
+++ b/absl/base/internal/spinlock.cc
@@ -57,8 +57,8 @@ namespace absl {
ABSL_NAMESPACE_BEGIN
namespace base_internal {
-ABSL_CONST_INIT static base_internal::AtomicHook<void (*)(const void *lock,
- int64_t wait_cycles)>
+ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES static base_internal::AtomicHook<void (*)(
+ const void *lock, int64_t wait_cycles)>
submit_profile_data;
void RegisterSpinLockProfiler(void (*fn)(const void *contendedlock,
diff --git a/absl/container/internal/btree.h b/absl/container/internal/btree.h
index 707e9f0e..8644255c 100644
--- a/absl/container/internal/btree.h
+++ b/absl/container/internal/btree.h
@@ -403,8 +403,9 @@ class btree_node {
// // TODO(ezb): right now, `start` is always 0. Update insertion/merge
// // logic to allow for floating storage within nodes.
// field_type start;
- // // The count of the number of populated values in the node.
- // field_type count;
+ // // The index after the last populated value in `values`. Currently, this
+ // // is the same as the count of values.
+ // field_type finish;
// // The maximum number of values the node can hold. This is an integer in
// // [1, kNodeValues] for root leaf nodes, kNodeValues for non-root leaf
// // nodes, and kInternalNodeMaxCount (as a sentinel value) for internal
@@ -415,7 +416,7 @@ class btree_node {
//
// // The array of values. The capacity is `max_count` for leaf nodes and
// // kNodeValues for internal nodes. Only the values in
- // // [start, start + count) have been initialized and are valid.
+ // // [start, finish) have been initialized and are valid.
// slot_type values[max_count];
//
// // The array of child pointers. The keys in children[i] are all less
@@ -446,7 +447,7 @@ class btree_node {
slot_type, btree_node *>;
constexpr static size_type SizeWithNValues(size_type n) {
return layout_type(/*parent*/ 1,
- /*position, start, count, max_count*/ 4,
+ /*position, start, finish, max_count*/ 4,
/*values*/ n,
/*children*/ 0)
.AllocSize();
@@ -483,13 +484,13 @@ class btree_node {
// Leaves can have less than kNodeValues values.
constexpr static layout_type LeafLayout(const int max_values = kNodeValues) {
return layout_type(/*parent*/ 1,
- /*position, start, count, max_count*/ 4,
+ /*position, start, finish, max_count*/ 4,
/*values*/ max_values,
/*children*/ 0);
}
constexpr static layout_type InternalLayout() {
return layout_type(/*parent*/ 1,
- /*position, start, count, max_count*/ 4,
+ /*position, start, finish, max_count*/ 4,
/*values*/ kNodeValues,
/*children*/ kNodeValues + 1);
}
@@ -515,12 +516,14 @@ class btree_node {
reinterpret_cast<const char *>(this));
}
void set_parent(btree_node *p) { *GetField<0>() = p; }
- field_type &mutable_count() { return GetField<1>()[2]; }
+ field_type &mutable_finish() { return GetField<1>()[2]; }
slot_type *slot(int i) { return &GetField<2>()[i]; }
+ slot_type *start_slot() { return slot(start()); }
+ slot_type *finish_slot() { return slot(finish()); }
const slot_type *slot(int i) const { return &GetField<2>()[i]; }
void set_position(field_type v) { GetField<1>()[0] = v; }
void set_start(field_type v) { GetField<1>()[1] = v; }
- void set_count(field_type v) { GetField<1>()[2] = v; }
+ void set_finish(field_type v) { GetField<1>()[2] = v; }
// This method is only called by the node init methods.
void set_max_count(field_type v) { GetField<1>()[3] = v; }
@@ -533,10 +536,20 @@ class btree_node {
field_type position() const { return GetField<1>()[0]; }
// Getter for the offset of the first value in the `values` array.
- field_type start() const { return GetField<1>()[1]; }
+ field_type start() const {
+ // TODO(ezb): when floating storage is implemented, return GetField<1>()[1];
+ assert(GetField<1>()[1] == 0);
+ return 0;
+ }
+
+ // Getter for the offset after the last value in the `values` array.
+ field_type finish() const { return GetField<1>()[2]; }
// Getters for the number of values stored in this node.
- field_type count() const { return GetField<1>()[2]; }
+ field_type count() const {
+ assert(finish() >= start());
+ return finish() - start();
+ }
field_type max_count() const {
// Internal nodes have max_count==kInternalNodeMaxCount.
// Leaf nodes have max_count in [1, kNodeValues].
@@ -564,6 +577,7 @@ class btree_node {
// Getters/setter for the child at position i in the node.
btree_node *child(int i) const { return GetField<3>()[i]; }
+ btree_node *start_child() const { return child(start()); }
btree_node *&mutable_child(int i) { return GetField<3>()[i]; }
void clear_child(int i) {
absl::container_internal::SanitizerPoisonObject(&mutable_child(i));
@@ -596,14 +610,14 @@ class btree_node {
template <typename K, typename Compare>
SearchResult<int, btree_is_key_compare_to<Compare, key_type>::value>
linear_search(const K &k, const Compare &comp) const {
- return linear_search_impl(k, 0, count(), comp,
+ return linear_search_impl(k, start(), finish(), comp,
btree_is_key_compare_to<Compare, key_type>());
}
template <typename K, typename Compare>
SearchResult<int, btree_is_key_compare_to<Compare, key_type>::value>
binary_search(const K &k, const Compare &comp) const {
- return binary_search_impl(k, 0, count(), comp,
+ return binary_search_impl(k, start(), finish(), comp,
btree_is_key_compare_to<Compare, key_type>());
}
@@ -733,10 +747,10 @@ class btree_node {
n->set_parent(parent);
n->set_position(0);
n->set_start(0);
- n->set_count(0);
+ n->set_finish(0);
n->set_max_count(max_count);
absl::container_internal::SanitizerPoisonMemoryRegion(
- n->slot(0), max_count * sizeof(slot_type));
+ n->start_slot(), max_count * sizeof(slot_type));
return n;
}
static btree_node *init_internal(btree_node *n, btree_node *parent) {
@@ -745,11 +759,12 @@ class btree_node {
// internal.
n->set_max_count(kInternalNodeMaxCount);
absl::container_internal::SanitizerPoisonMemoryRegion(
- &n->mutable_child(0), (kNodeValues + 1) * sizeof(btree_node *));
+ &n->mutable_child(n->start()),
+ (kNodeValues + 1) * sizeof(btree_node *));
return n;
}
void destroy(allocator_type *alloc) {
- for (int i = 0; i < count(); ++i) {
+ for (int i = start(); i < finish(); ++i) {
value_destroy(i, alloc);
}
}
@@ -829,6 +844,7 @@ struct btree_iterator {
using iterator_category = std::bidirectional_iterator_tag;
btree_iterator() : node(nullptr), position(-1) {}
+ explicit btree_iterator(Node *n) : node(n), position(n->start()) {}
btree_iterator(Node *n, int p) : node(n), position(p) {}
// NOTE: this SFINAE allows for implicit conversions from iterator to
@@ -858,7 +874,7 @@ struct btree_iterator {
// Increment/decrement the iterator.
void increment() {
- if (node->leaf() && ++position < node->count()) {
+ if (node->leaf() && ++position < node->finish()) {
return;
}
increment_slow();
@@ -866,7 +882,7 @@ struct btree_iterator {
void increment_slow();
void decrement() {
- if (node->leaf() && --position >= 0) {
+ if (node->leaf() && --position >= node->start()) {
return;
}
decrement_slow();
@@ -942,7 +958,7 @@ class btree {
node_type *parent;
field_type position = 0;
field_type start = 0;
- field_type count = 0;
+ field_type finish = 0;
// max_count must be != kInternalNodeMaxCount (so that this node is regarded
// as a leaf node). max_count() is never called when the tree is empty.
field_type max_count = node_type::kInternalNodeMaxCount + 1;
@@ -1047,11 +1063,11 @@ class btree {
btree &operator=(const btree &x);
btree &operator=(btree &&x) noexcept;
- iterator begin() { return iterator(leftmost(), 0); }
- const_iterator begin() const { return const_iterator(leftmost(), 0); }
- iterator end() { return iterator(rightmost_, rightmost_->count()); }
+ iterator begin() { return iterator(leftmost()); }
+ const_iterator begin() const { return const_iterator(leftmost()); }
+ iterator end() { return iterator(rightmost_, rightmost_->finish()); }
const_iterator end() const {
- return const_iterator(rightmost_, rightmost_->count());
+ return const_iterator(rightmost_, rightmost_->finish());
}
reverse_iterator rbegin() { return reverse_iterator(end()); }
const_reverse_iterator rbegin() const {
@@ -1367,9 +1383,9 @@ class btree {
iterator internal_emplace(iterator iter, Args &&... args);
// Returns an iterator pointing to the first value >= the value "iter" is
- // pointing at. Note that "iter" might be pointing to an invalid location as
- // iter.position == iter.node->count(). This routine simply moves iter up in
- // the tree to a valid location.
+ // pointing at. Note that "iter" might be pointing to an invalid location such
+ // as iter.position == iter.node->finish(). This routine simply moves iter up
+ // in the tree to a valid location.
// Requires: iter.node is non-null.
template <typename IterType>
static IterType internal_last(IterType iter);
@@ -1422,7 +1438,7 @@ class btree {
return node_stats(1, 0);
}
node_stats res(0, 1);
- for (int i = 0; i <= node->count(); ++i) {
+ for (int i = node->start(); i <= node->finish(); ++i) {
res += internal_stats(node->child(i));
}
return res;
@@ -1456,20 +1472,21 @@ template <typename... Args>
inline void btree_node<P>::emplace_value(const size_type i,
allocator_type *alloc,
Args &&... args) {
- assert(i <= count());
+ assert(i >= start());
+ assert(i <= finish());
// Shift old values to create space for new value and then construct it in
// place.
- if (i < count()) {
- value_init(count(), alloc, slot(count() - 1));
- for (size_type j = count() - 1; j > i; --j)
+ if (i < finish()) {
+ value_init(finish(), alloc, slot(finish() - 1));
+ for (size_type j = finish() - 1; j > i; --j)
params_type::move(alloc, slot(j - 1), slot(j));
value_destroy(i, alloc);
}
value_init(i, alloc, std::forward<Args>(args)...);
- set_count(count() + 1);
+ set_finish(finish() + 1);
- if (!leaf() && count() > i + 1) {
- for (int j = count(); j > i + 1; --j) {
+ if (!leaf() && finish() > i + 1) {
+ for (int j = finish(); j > i + 1; --j) {
set_child(j, child(j - 1));
}
clear_child(i + 1);
@@ -1478,12 +1495,12 @@ inline void btree_node<P>::emplace_value(const size_type i,
template <typename P>
inline void btree_node<P>::remove_value(const int i, allocator_type *alloc) {
- if (!leaf() && count() > i + 1) {
+ if (!leaf() && finish() > i + 1) {
assert(child(i + 1)->count() == 0);
- for (size_type j = i + 1; j < count(); ++j) {
+ for (size_type j = i + 1; j < finish(); ++j) {
set_child(j, child(j + 1));
}
- clear_child(count());
+ clear_child(finish());
}
remove_values_ignore_children(i, /*to_erase=*/1, alloc);
@@ -1492,9 +1509,9 @@ inline void btree_node<P>::remove_value(const int i, allocator_type *alloc) {
template <typename P>
inline void btree_node<P>::remove_values_ignore_children(
const int i, const int to_erase, allocator_type *alloc) {
- params_type::move(alloc, slot(i + to_erase), slot(count()), slot(i));
- value_destroy_n(count() - to_erase, to_erase, alloc);
- set_count(count() - to_erase);
+ params_type::move(alloc, slot(i + to_erase), finish_slot(), slot(i));
+ value_destroy_n(finish() - to_erase, to_erase, alloc);
+ set_finish(finish() - to_erase);
}
template <typename P>
@@ -1508,37 +1525,38 @@ void btree_node<P>::rebalance_right_to_left(const int to_move,
assert(to_move <= right->count());
// 1) Move the delimiting value in the parent to the left node.
- value_init(count(), alloc, parent()->slot(position()));
+ value_init(finish(), alloc, parent()->slot(position()));
// 2) Move the (to_move - 1) values from the right node to the left node.
- right->uninitialized_move_n(to_move - 1, 0, count() + 1, this, alloc);
+ right->uninitialized_move_n(to_move - 1, right->start(), finish() + 1, this,
+ alloc);
// 3) Move the new delimiting value to the parent from the right node.
params_type::move(alloc, right->slot(to_move - 1),
parent()->slot(position()));
// 4) Shift the values in the right node to their correct position.
- params_type::move(alloc, right->slot(to_move), right->slot(right->count()),
- right->slot(0));
+ params_type::move(alloc, right->slot(to_move), right->finish_slot(),
+ right->start_slot());
// 5) Destroy the now-empty to_move entries in the right node.
- right->value_destroy_n(right->count() - to_move, to_move, alloc);
+ right->value_destroy_n(right->finish() - to_move, to_move, alloc);
if (!leaf()) {
// Move the child pointers from the right to the left node.
for (int i = 0; i < to_move; ++i) {
- init_child(count() + i + 1, right->child(i));
+ init_child(finish() + i + 1, right->child(i));
}
- for (int i = 0; i <= right->count() - to_move; ++i) {
+ for (int i = right->start(); i <= right->finish() - to_move; ++i) {
assert(i + to_move <= right->max_count());
right->init_child(i, right->child(i + to_move));
right->clear_child(i + to_move);
}
}
- // Fixup the counts on the left and right nodes.
- set_count(count() + to_move);
- right->set_count(right->count() - to_move);
+ // Fixup `finish` on the left and right nodes.
+ set_finish(finish() + to_move);
+ right->set_finish(right->finish() - to_move);
}
template <typename P>
@@ -1562,11 +1580,11 @@ void btree_node<P>::rebalance_left_to_right(const int to_move,
// the new to_move entries from the parent and left node.
// 1) Shift existing values in the right node to their correct positions.
- right->uninitialized_move_n(to_move, right->count() - to_move,
- right->count(), right, alloc);
- for (slot_type *src = right->slot(right->count() - to_move - 1),
- *dest = right->slot(right->count() - 1),
- *end = right->slot(0);
+ right->uninitialized_move_n(to_move, right->finish() - to_move,
+ right->finish(), right, alloc);
+ for (slot_type *src = right->slot(right->finish() - to_move - 1),
+ *dest = right->slot(right->finish() - 1),
+ *end = right->start_slot();
src >= end; --src, --dest) {
params_type::move(alloc, src, dest);
}
@@ -1576,14 +1594,15 @@ void btree_node<P>::rebalance_left_to_right(const int to_move,
right->slot(to_move - 1));
// 3) Move the (to_move - 1) values from the left node to the right node.
- params_type::move(alloc, slot(count() - (to_move - 1)), slot(count()),
- right->slot(0));
+ params_type::move(alloc, slot(finish() - (to_move - 1)), finish_slot(),
+ right->start_slot());
} else {
// The right node does not have enough initialized space to hold the new
// to_move entries, so part of them will move to uninitialized space.
// 1) Shift existing values in the right node to their correct positions.
- right->uninitialized_move_n(right->count(), 0, to_move, right, alloc);
+ right->uninitialized_move_n(right->count(), right->start(),
+ right->start() + to_move, right, alloc);
// 2) Move the delimiting value in the parent to the right node.
right->value_init(to_move - 1, alloc, parent()->slot(position()));
@@ -1591,33 +1610,35 @@ void btree_node<P>::rebalance_left_to_right(const int to_move,
// 3) Move the (to_move - 1) values from the left node to the right node.
const size_type uninitialized_remaining = to_move - right->count() - 1;
uninitialized_move_n(uninitialized_remaining,
- count() - uninitialized_remaining, right->count(),
+ finish() - uninitialized_remaining, right->finish(),
right, alloc);
- params_type::move(alloc, slot(count() - (to_move - 1)),
- slot(count() - uninitialized_remaining), right->slot(0));
+ params_type::move(alloc, slot(finish() - (to_move - 1)),
+ slot(finish() - uninitialized_remaining),
+ right->start_slot());
}
// 4) Move the new delimiting value to the parent from the left node.
- params_type::move(alloc, slot(count() - to_move), parent()->slot(position()));
+ params_type::move(alloc, slot(finish() - to_move),
+ parent()->slot(position()));
// 5) Destroy the now-empty to_move entries in the left node.
- value_destroy_n(count() - to_move, to_move, alloc);
+ value_destroy_n(finish() - to_move, to_move, alloc);
if (!leaf()) {
// Move the child pointers from the left to the right node.
- for (int i = right->count(); i >= 0; --i) {
+ for (int i = right->finish(); i >= right->start(); --i) {
right->init_child(i + to_move, right->child(i));
right->clear_child(i);
}
for (int i = 1; i <= to_move; ++i) {
- right->init_child(i - 1, child(count() - to_move + i));
- clear_child(count() - to_move + i);
+ right->init_child(i - 1, child(finish() - to_move + i));
+ clear_child(finish() - to_move + i);
}
}
// Fixup the counts on the left and right nodes.
- set_count(count() - to_move);
- right->set_count(right->count() + to_move);
+ set_finish(finish() - to_move);
+ right->set_finish(right->finish() + to_move);
}
template <typename P>
@@ -1630,33 +1651,34 @@ void btree_node<P>::split(const int insert_position, btree_node *dest,
// inserting at the beginning of the left node then bias the split to put
// more values on the right node. If we're inserting at the end of the
// right node then bias the split to put more values on the left node.
- if (insert_position == 0) {
- dest->set_count(count() - 1);
+ if (insert_position == start()) {
+ dest->set_finish(dest->start() + finish() - 1);
} else if (insert_position == kNodeValues) {
- dest->set_count(0);
+ dest->set_finish(dest->start());
} else {
- dest->set_count(count() / 2);
+ dest->set_finish(dest->start() + count() / 2);
}
- set_count(count() - dest->count());
+ set_finish(finish() - dest->count());
assert(count() >= 1);
// Move values from the left sibling to the right sibling.
- uninitialized_move_n(dest->count(), count(), 0, dest, alloc);
+ uninitialized_move_n(dest->count(), finish(), dest->start(), dest, alloc);
// Destroy the now-empty entries in the left node.
- value_destroy_n(count(), dest->count(), alloc);
+ value_destroy_n(finish(), dest->count(), alloc);
// The split key is the largest value in the left sibling.
- set_count(count() - 1);
- parent()->emplace_value(position(), alloc, slot(count()));
- value_destroy(count(), alloc);
+ --mutable_finish();
+ parent()->emplace_value(position(), alloc, finish_slot());
+ value_destroy(finish(), alloc);
parent()->init_child(position() + 1, dest);
if (!leaf()) {
- for (int i = 0; i <= dest->count(); ++i) {
- assert(child(count() + i + 1) != nullptr);
- dest->init_child(i, child(count() + i + 1));
- clear_child(count() + i + 1);
+ for (int i = dest->start(), j = finish() + 1; i <= dest->finish();
+ ++i, ++j) {
+ assert(child(j) != nullptr);
+ dest->init_child(i, child(j));
+ clear_child(j);
}
}
}
@@ -1667,25 +1689,26 @@ void btree_node<P>::merge(btree_node *src, allocator_type *alloc) {
assert(position() + 1 == src->position());
// Move the delimiting value to the left node.
- value_init(count(), alloc, parent()->slot(position()));
+ value_init(finish(), alloc, parent()->slot(position()));
// Move the values from the right to the left node.
- src->uninitialized_move_n(src->count(), 0, count() + 1, this, alloc);
+ src->uninitialized_move_n(src->count(), src->start(), finish() + 1, this,
+ alloc);
// Destroy the now-empty entries in the right node.
- src->value_destroy_n(0, src->count(), alloc);
+ src->value_destroy_n(src->start(), src->count(), alloc);
if (!leaf()) {
// Move the child pointers from the right to the left node.
- for (int i = 0; i <= src->count(); ++i) {
- init_child(count() + i + 1, src->child(i));
+ for (int i = src->start(), j = finish() + 1; i <= src->finish(); ++i, ++j) {
+ init_child(j, src->child(i));
src->clear_child(i);
}
}
- // Fixup the counts on the src and dest nodes.
- set_count(1 + count() + src->count());
- src->set_count(0);
+ // Fixup `finish` on the src and dest nodes.
+ set_finish(start() + 1 + count() + src->count());
+ src->set_finish(src->start());
// Remove the value on the parent node.
parent()->remove_value(position(), alloc);
@@ -1703,38 +1726,40 @@ void btree_node<P>::swap(btree_node *x, allocator_type *alloc) {
}
// Swap the values.
- for (slot_type *a = smaller->slot(0), *b = larger->slot(0),
- *end = a + smaller->count();
+ for (slot_type *a = smaller->start_slot(), *b = larger->start_slot(),
+ *end = smaller->finish_slot();
a != end; ++a, ++b) {
params_type::swap(alloc, a, b);
}
// Move values that can't be swapped.
const size_type to_move = larger->count() - smaller->count();
- larger->uninitialized_move_n(to_move, smaller->count(), smaller->count(),
+ larger->uninitialized_move_n(to_move, smaller->finish(), smaller->finish(),
smaller, alloc);
- larger->value_destroy_n(smaller->count(), to_move, alloc);
+ larger->value_destroy_n(smaller->finish(), to_move, alloc);
if (!leaf()) {
// Swap the child pointers.
- std::swap_ranges(&smaller->mutable_child(0),
- &smaller->mutable_child(smaller->count() + 1),
- &larger->mutable_child(0));
+ std::swap_ranges(&smaller->mutable_child(smaller->start()),
+ &smaller->mutable_child(smaller->finish() + 1),
+ &larger->mutable_child(larger->start()));
// Update swapped children's parent pointers.
- int i = 0;
- for (; i <= smaller->count(); ++i) {
+ int i = smaller->start();
+ int j = larger->start();
+ for (; i <= smaller->finish(); ++i, ++j) {
smaller->child(i)->set_parent(smaller);
- larger->child(i)->set_parent(larger);
+ larger->child(j)->set_parent(larger);
}
// Move the child pointers that couldn't be swapped.
- for (; i <= larger->count(); ++i) {
- smaller->init_child(i, larger->child(i));
- larger->clear_child(i);
+ for (; j <= larger->finish(); ++i, ++j) {
+ smaller->init_child(i, larger->child(j));
+ larger->clear_child(j);
}
}
- // Swap the counts.
- swap(mutable_count(), x->mutable_count());
+ // Swap the `finish`s.
+ // TODO(ezb): with floating storage, will also need to swap starts.
+ swap(mutable_finish(), x->mutable_finish());
}
////
@@ -1742,23 +1767,23 @@ void btree_node<P>::swap(btree_node *x, allocator_type *alloc) {
template <typename N, typename R, typename P>
void btree_iterator<N, R, P>::increment_slow() {
if (node->leaf()) {
- assert(position >= node->count());
+ assert(position >= node->finish());
btree_iterator save(*this);
- while (position == node->count() && !node->is_root()) {
+ while (position == node->finish() && !node->is_root()) {
assert(node->parent()->child(node->position()) == node);
position = node->position();
node = node->parent();
}
- if (position == node->count()) {
+ if (position == node->finish()) {
*this = save;
}
} else {
- assert(position < node->count());
+ assert(position < node->finish());
node = node->child(position + 1);
while (!node->leaf()) {
- node = node->child(0);
+ node = node->start_child();
}
- position = 0;
+ position = node->start();
}
}
@@ -1767,21 +1792,21 @@ void btree_iterator<N, R, P>::decrement_slow() {
if (node->leaf()) {
assert(position <= -1);
btree_iterator save(*this);
- while (position < 0 && !node->is_root()) {
+ while (position < node->start() && !node->is_root()) {
assert(node->parent()->child(node->position()) == node);
position = node->position() - 1;
node = node->parent();
}
- if (position < 0) {
+ if (position < node->start()) {
*this = save;
}
} else {
- assert(position >= 0);
+ assert(position >= node->start());
node = node->child(position);
while (!node->leaf()) {
- node = node->child(node->count());
+ node = node->child(node->finish());
}
- position = node->count() - 1;
+ position = node->finish() - 1;
}
}
@@ -2068,8 +2093,8 @@ auto btree<P>::rebalance_after_delete(iterator iter) -> iterator {
// Adjust our return value. If we're pointing at the end of a node, advance
// the iterator.
- if (res.position == res.node->count()) {
- res.position = res.node->count() - 1;
+ if (res.position == res.node->finish()) {
+ res.position = res.node->finish() - 1;
++res;
}
@@ -2101,7 +2126,7 @@ auto btree<P>::erase_range(iterator begin, iterator end)
while (size_ > target_size) {
if (begin.node->leaf()) {
const size_type remaining_to_erase = size_ - target_size;
- const size_type remaining_in_node = begin.node->count() - begin.position;
+ const size_type remaining_in_node = begin.node->finish() - begin.position;
begin = erase_from_leaf_node(
begin, (std::min)(remaining_to_erase, remaining_in_node));
} else {
@@ -2124,7 +2149,8 @@ void btree<P>::erase_same_node(iterator begin, iterator end) {
internal_clear(node->child(begin.position + i + 1));
}
// Rotate children after end into new positions.
- for (size_type i = begin.position + to_erase + 1; i <= node->count(); ++i) {
+ for (size_type i = begin.position + to_erase + 1; i <= node->finish();
+ ++i) {
node->set_child(i - to_erase, node->child(i));
node->clear_child(i);
}
@@ -2144,8 +2170,8 @@ auto btree<P>::erase_from_leaf_node(iterator begin, size_type to_erase)
-> iterator {
node_type *node = begin.node;
assert(node->leaf());
- assert(node->count() > begin.position);
- assert(begin.position + to_erase <= node->count());
+ assert(node->finish() > begin.position);
+ assert(begin.position + to_erase <= node->finish());
node->remove_values_ignore_children(begin.position, to_erase,
mutable_allocator());
@@ -2214,7 +2240,7 @@ void btree<P>::verify() const {
assert(rightmost_ != nullptr);
assert(empty() || size() == internal_verify(root(), nullptr, nullptr));
assert(leftmost() == (++const_iterator(root(), -1)).node);
- assert(rightmost_ == (--const_iterator(root(), root()->count())).node);
+ assert(rightmost_ == (--const_iterator(root(), root()->finish())).node);
assert(leftmost()->leaf());
assert(rightmost_->leaf());
}
@@ -2229,7 +2255,7 @@ void btree<P>::rebalance_or_split(iterator *iter) {
// First try to make room on the node by rebalancing.
node_type *parent = node->parent();
if (node != root()) {
- if (node->position() > 0) {
+ if (node->position() > parent->start()) {
// Try rebalancing with our left sibling.
node_type *left = parent->child(node->position() - 1);
assert(left->max_count() == kNodeValues);
@@ -2241,13 +2267,13 @@ void btree<P>::rebalance_or_split(iterator *iter) {
(1 + (insert_position < kNodeValues));
to_move = (std::max)(1, to_move);
- if (((insert_position - to_move) >= 0) ||
- ((left->count() + to_move) < kNodeValues)) {
+ if (insert_position - to_move >= node->start() ||
+ left->count() + to_move < kNodeValues) {
left->rebalance_right_to_left(to_move, node, mutable_allocator());
assert(node->max_count() - node->count() == to_move);
insert_position = insert_position - to_move;
- if (insert_position < 0) {
+ if (insert_position < node->start()) {
insert_position = insert_position + left->count() + 1;
node = left;
}
@@ -2258,7 +2284,7 @@ void btree<P>::rebalance_or_split(iterator *iter) {
}
}
- if (node->position() < parent->count()) {
+ if (node->position() < parent->finish()) {
// Try rebalancing with our right sibling.
node_type *right = parent->child(node->position() + 1);
assert(right->max_count() == kNodeValues);
@@ -2266,15 +2292,15 @@ void btree<P>::rebalance_or_split(iterator *iter) {
// We bias rebalancing based on the position being inserted. If we're
// inserting at the beginning of the left node then we bias rebalancing
// to fill up the right node.
- int to_move =
- (kNodeValues - right->count()) / (1 + (insert_position > 0));
+ int to_move = (kNodeValues - right->count()) /
+ (1 + (insert_position > node->start()));
to_move = (std::max)(1, to_move);
- if ((insert_position <= (node->count() - to_move)) ||
- ((right->count() + to_move) < kNodeValues)) {
+ if (insert_position <= node->finish() - to_move ||
+ right->count() + to_move < kNodeValues) {
node->rebalance_left_to_right(to_move, right, mutable_allocator());
- if (insert_position > node->count()) {
+ if (insert_position > node->finish()) {
insert_position = insert_position - node->count() - 1;
node = right;
}
@@ -2297,10 +2323,11 @@ void btree<P>::rebalance_or_split(iterator *iter) {
// Create a new root node and set the current root node as the child of the
// new root.
parent = new_internal_node(parent);
- parent->init_child(0, root());
+ parent->init_child(parent->start(), root());
mutable_root() = parent;
// If the former root was a leaf node, then it's now the rightmost node.
- assert(!parent->child(0)->leaf() || parent->child(0) == rightmost_);
+ assert(!parent->start_child()->leaf() ||
+ parent->start_child() == rightmost_);
}
// Split the node.
@@ -2314,7 +2341,7 @@ void btree<P>::rebalance_or_split(iterator *iter) {
node->split(insert_position, split_node, mutable_allocator());
}
- if (insert_position > node->count()) {
+ if (insert_position > node->finish()) {
insert_position = insert_position - node->count() - 1;
node = split_node;
}
@@ -2334,22 +2361,22 @@ void btree<P>::merge_nodes(node_type *left, node_type *right) {
template <typename P>
bool btree<P>::try_merge_or_rebalance(iterator *iter) {
node_type *parent = iter->node->parent();
- if (iter->node->position() > 0) {
+ if (iter->node->position() > parent->start()) {
// Try merging with our left sibling.
node_type *left = parent->child(iter->node->position() - 1);
assert(left->max_count() == kNodeValues);
- if ((1 + left->count() + iter->node->count()) <= kNodeValues) {
+ if (1 + left->count() + iter->node->count() <= kNodeValues) {
iter->position += 1 + left->count();
merge_nodes(left, iter->node);
iter->node = left;
return true;
}
}
- if (iter->node->position() < parent->count()) {
+ if (iter->node->position() < parent->finish()) {
// Try merging with our right sibling.
node_type *right = parent->child(iter->node->position() + 1);
assert(right->max_count() == kNodeValues);
- if ((1 + iter->node->count() + right->count()) <= kNodeValues) {
+ if (1 + iter->node->count() + right->count() <= kNodeValues) {
merge_nodes(iter->node, right);
return true;
}
@@ -2357,23 +2384,22 @@ bool btree<P>::try_merge_or_rebalance(iterator *iter) {
// we deleted the first element from iter->node and the node is not
// empty. This is a small optimization for the common pattern of deleting
// from the front of the tree.
- if ((right->count() > kMinNodeValues) &&
- ((iter->node->count() == 0) || (iter->position > 0))) {
+ if (right->count() > kMinNodeValues &&
+ (iter->node->count() == 0 || iter->position > iter->node->start())) {
int to_move = (right->count() - iter->node->count()) / 2;
to_move = (std::min)(to_move, right->count() - 1);
iter->node->rebalance_right_to_left(to_move, right, mutable_allocator());
return false;
}
}
- if (iter->node->position() > 0) {
+ if (iter->node->position() > parent->start()) {
// Try rebalancing with our left sibling. We don't perform rebalancing if
// we deleted the last element from iter->node and the node is not
// empty. This is a small optimization for the common pattern of deleting
// from the back of the tree.
node_type *left = parent->child(iter->node->position() - 1);
- if ((left->count() > kMinNodeValues) &&
- ((iter->node->count() == 0) ||
- (iter->position < iter->node->count()))) {
+ if (left->count() > kMinNodeValues &&
+ (iter->node->count() == 0 || iter->position < iter->node->finish())) {
int to_move = (left->count() - iter->node->count()) / 2;
to_move = (std::min)(to_move, left->count() - 1);
left->rebalance_left_to_right(to_move, iter->node, mutable_allocator());
@@ -2396,7 +2422,7 @@ void btree<P>::try_shrink() {
mutable_root() = EmptyNode();
rightmost_ = EmptyNode();
} else {
- node_type *child = root()->child(0);
+ node_type *child = root()->start_child();
child->make_root();
delete_internal_node(root());
mutable_root() = child;
@@ -2407,7 +2433,7 @@ template <typename P>
template <typename IterType>
inline IterType btree<P>::internal_last(IterType iter) {
assert(iter.node != nullptr);
- while (iter.position == iter.node->count()) {
+ while (iter.position == iter.node->finish()) {
iter.position = iter.node->position();
iter.node = iter.node->parent();
if (iter.node->leaf()) {
@@ -2463,7 +2489,7 @@ template <typename K>
inline auto btree<P>::internal_locate_impl(
const K &key, std::false_type /* IsCompareTo */) const
-> SearchResult<iterator, false> {
- iterator iter(const_cast<node_type *>(root()), 0);
+ iterator iter(const_cast<node_type *>(root()));
for (;;) {
iter.position = iter.node->lower_bound(key, key_comp()).value;
// NOTE: we don't need to walk all the way down the tree if the keys are
@@ -2483,7 +2509,7 @@ template <typename K>
inline auto btree<P>::internal_locate_impl(
const K &key, std::true_type /* IsCompareTo */) const
-> SearchResult<iterator, true> {
- iterator iter(const_cast<node_type *>(root()), 0);
+ iterator iter(const_cast<node_type *>(root()));
for (;;) {
SearchResult<int, true> res = iter.node->lower_bound(key, key_comp());
iter.position = res.value;
@@ -2501,7 +2527,7 @@ inline auto btree<P>::internal_locate_impl(
template <typename P>
template <typename K>
auto btree<P>::internal_lower_bound(const K &key) const -> iterator {
- iterator iter(const_cast<node_type *>(root()), 0);
+ iterator iter(const_cast<node_type *>(root()));
for (;;) {
iter.position = iter.node->lower_bound(key, key_comp()).value;
if (iter.node->leaf()) {
@@ -2515,7 +2541,7 @@ auto btree<P>::internal_lower_bound(const K &key) const -> iterator {
template <typename P>
template <typename K>
auto btree<P>::internal_upper_bound(const K &key) const -> iterator {
- iterator iter(const_cast<node_type *>(root()), 0);
+ iterator iter(const_cast<node_type *>(root()));
for (;;) {
iter.position = iter.node->upper_bound(key, key_comp());
if (iter.node->leaf()) {
@@ -2546,7 +2572,7 @@ auto btree<P>::internal_find(const K &key) const -> iterator {
template <typename P>
void btree<P>::internal_clear(node_type *node) {
if (!node->leaf()) {
- for (int i = 0; i <= node->count(); ++i) {
+ for (int i = node->start(); i <= node->finish(); ++i) {
internal_clear(node->child(i));
}
delete_internal_node(node);
@@ -2561,23 +2587,23 @@ int btree<P>::internal_verify(const node_type *node, const key_type *lo,
assert(node->count() > 0);
assert(node->count() <= node->max_count());
if (lo) {
- assert(!compare_keys(node->key(0), *lo));
+ assert(!compare_keys(node->key(node->start()), *lo));
}
if (hi) {
- assert(!compare_keys(*hi, node->key(node->count() - 1)));
+ assert(!compare_keys(*hi, node->key(node->finish() - 1)));
}
- for (int i = 1; i < node->count(); ++i) {
+ for (int i = node->start() + 1; i < node->finish(); ++i) {
assert(!compare_keys(node->key(i), node->key(i - 1)));
}
int count = node->count();
if (!node->leaf()) {
- for (int i = 0; i <= node->count(); ++i) {
+ for (int i = node->start(); i <= node->finish(); ++i) {
assert(node->child(i) != nullptr);
assert(node->child(i)->parent() == node);
assert(node->child(i)->position() == i);
- count +=
- internal_verify(node->child(i), (i == 0) ? lo : &node->key(i - 1),
- (i == node->count()) ? hi : &node->key(i));
+ count += internal_verify(node->child(i),
+ i == node->start() ? lo : &node->key(i - 1),
+ i == node->finish() ? hi : &node->key(i));
}
}
return count;
diff --git a/absl/flags/flag.h b/absl/flags/flag.h
index bd61668f..fcfdd58c 100644
--- a/absl/flags/flag.h
+++ b/absl/flags/flag.h
@@ -186,15 +186,17 @@ class Flag {
//
// // FLAGS_firstname is a Flag of type `std::string`
// std::string first_name = absl::GetFlag(FLAGS_firstname);
+template <typename T>
+ABSL_MUST_USE_RESULT T GetFlag(const absl::Flag<T>& flag) {
+ return flag.Get();
+}
+
#ifndef NDEBUG
// We want to validate the type mismatch between type definition and
// declaration. The lock-free implementation does not allow us to do it,
// so in debug builds we always use the slower implementation, which always
// validates the type.
-template <typename T>
-ABSL_MUST_USE_RESULT T GetFlag(const absl::Flag<T>& flag) {
- return flag.Get();
-}
+
// We currently need an external linkage for built-in types because shared
// libraries have different addresses of flags_internal::FlagOps<T> which
// might cause log spam when checking the same flag type.
@@ -202,29 +204,6 @@ ABSL_MUST_USE_RESULT T GetFlag(const absl::Flag<T>& flag) {
ABSL_MUST_USE_RESULT T GetFlag(const absl::Flag<T>& flag);
ABSL_FLAGS_INTERNAL_BUILTIN_TYPES(ABSL_FLAGS_INTERNAL_BUILT_IN_EXPORT)
#undef ABSL_FLAGS_INTERNAL_BUILT_IN_EXPORT
-#else
-template <typename T,
- typename std::enable_if<
- !flags_internal::IsAtomicFlagTypeTrait<T>::value, int>::type = 0>
-ABSL_MUST_USE_RESULT T GetFlag(const absl::Flag<T>& flag) {
- return flag.Get();
-}
-// Overload for `GetFlag()` for types that support lock-free reads.
-template <typename T,
- typename std::enable_if<
- flags_internal::IsAtomicFlagTypeTrait<T>::value, int>::type = 0>
-ABSL_MUST_USE_RESULT T GetFlag(const absl::Flag<T>& flag) {
- // T might not be default constructible.
- union U {
- T value;
- U() {}
- };
- U result;
- if (flag.AtomicGet(&result.value)) {
- return result.value;
- }
- return flag.Get();
-}
#endif
// SetFlag()
diff --git a/absl/flags/internal/flag.h b/absl/flags/internal/flag.h
index ec467c31..4341f113 100644
--- a/absl/flags/internal/flag.h
+++ b/absl/flags/internal/flag.h
@@ -244,16 +244,32 @@ class FlagImpl {
bool TryParse(void** dst, absl::string_view value, std::string* err) const
ABSL_EXCLUSIVE_LOCKS_REQUIRED(*DataGuard());
+#ifndef NDEBUG
template <typename T>
- bool AtomicGet(T* v) const {
+ void Get(T* dst) const {
+ Read(dst, &flags_internal::FlagOps<T>);
+ }
+#else
+ template <typename T, typename std::enable_if<
+ !flags_internal::IsAtomicFlagTypeTrait<T>::value,
+ int>::type = 0>
+ void Get(T* dst) const {
+ Read(dst, &flags_internal::FlagOps<T>);
+ }
+ // Overload for `GetFlag()` for types that support lock-free reads.
+ template <typename T,
+ typename std::enable_if<
+ flags_internal::IsAtomicFlagTypeTrait<T>::value, int>::type = 0>
+ void Get(T* dst) const {
using U = flags_internal::BestAtomicType<T>;
const typename U::type r = atomics_.template load<T>();
if (r != U::AtomicInit()) {
- std::memcpy(static_cast<void*>(v), &r, sizeof(T));
- return true;
+ std::memcpy(static_cast<void*>(dst), &r, sizeof(T));
+ } else {
+ Read(dst, &flags_internal::FlagOps<T>);
}
- return false;
}
+#endif
// Mutating access methods
void Write(const void* src, const flags_internal::FlagOpFn src_op)
@@ -397,12 +413,10 @@ class Flag final : public flags_internal::CommandLineFlag {
};
U u;
- impl_.Read(&u.value, &flags_internal::FlagOps<T>);
+ impl_.Get(&u.value);
return std::move(u.value);
}
- bool AtomicGet(T* v) const { return impl_.AtomicGet(v); }
-
void Set(const T& v) { impl_.Write(&v, &flags_internal::FlagOps<T>); }
void SetCallback(const flags_internal::FlagCallback mutation_callback) {
diff --git a/absl/random/distributions.h b/absl/random/distributions.h
index c1fb6650..d026d92b 100644
--- a/absl/random/distributions.h
+++ b/absl/random/distributions.h
@@ -291,10 +291,10 @@ RealType Beta(URBG&& urbg, // NOLINT(runtime/references)
// absl::Exponential<T>(bitgen, lambda = 1)
// -----------------------------------------------------------------------------
//
-// `absl::Exponential` produces a floating point number for discrete
-// distributions of events occurring continuously and independently at a
-// constant average rate. `T` must be a floating point type, but may be inferred
-// from the type of `lambda`.
+// `absl::Exponential` produces a floating point number representing the
+// distance (time) between two consecutive events in a point process of events
+// occurring continuously and independently at a constant average rate. `T` must
+// be a floating point type, but may be inferred from the type of `lambda`.
//
// See https://en.wikipedia.org/wiki/Exponential_distribution.
//
diff --git a/absl/strings/charconv.cc b/absl/strings/charconv.cc
index d9bc2dd2..bdba768d 100644
--- a/absl/strings/charconv.cc
+++ b/absl/strings/charconv.cc
@@ -673,7 +673,6 @@ from_chars_result FromCharsImpl(const char* first, const char* last,
EncodeResult(calculated, negative, &result, &value);
return result;
}
- return result;
}
} // namespace
diff --git a/absl/strings/string_view_benchmark.cc b/absl/strings/string_view_benchmark.cc
index f2e4214c..0d74e23e 100644
--- a/absl/strings/string_view_benchmark.cc
+++ b/absl/strings/string_view_benchmark.cc
@@ -160,11 +160,45 @@ void BM_CompareSame(benchmark::State& state) {
absl::string_view b = y;
for (auto _ : state) {
+ benchmark::DoNotOptimize(a);
+ benchmark::DoNotOptimize(b);
benchmark::DoNotOptimize(a.compare(b));
}
}
BENCHMARK(BM_CompareSame)->DenseRange(0, 3)->Range(4, 1 << 10);
+void BM_CompareFirstOneLess(benchmark::State& state) {
+ const int len = state.range(0);
+ std::string x(len, 'a');
+ std::string y = x;
+ y.back() = 'b';
+ absl::string_view a = x;
+ absl::string_view b = y;
+
+ for (auto _ : state) {
+ benchmark::DoNotOptimize(a);
+ benchmark::DoNotOptimize(b);
+ benchmark::DoNotOptimize(a.compare(b));
+ }
+}
+BENCHMARK(BM_CompareFirstOneLess)->DenseRange(1, 3)->Range(4, 1 << 10);
+
+void BM_CompareSecondOneLess(benchmark::State& state) {
+ const int len = state.range(0);
+ std::string x(len, 'a');
+ std::string y = x;
+ x.back() = 'b';
+ absl::string_view a = x;
+ absl::string_view b = y;
+
+ for (auto _ : state) {
+ benchmark::DoNotOptimize(a);
+ benchmark::DoNotOptimize(b);
+ benchmark::DoNotOptimize(a.compare(b));
+ }
+}
+BENCHMARK(BM_CompareSecondOneLess)->DenseRange(1, 3)->Range(4, 1 << 10);
+
void BM_find_string_view_len_one(benchmark::State& state) {
std::string haystack(state.range(0), '0');
absl::string_view s(haystack);
diff --git a/absl/synchronization/mutex.cc b/absl/synchronization/mutex.cc
index 46af8a52..e0879b05 100644
--- a/absl/synchronization/mutex.cc
+++ b/absl/synchronization/mutex.cc
@@ -107,13 +107,16 @@ static_assert(
sizeof(MutexGlobals) == ABSL_CACHELINE_SIZE,
"MutexGlobals must occupy an entire cacheline to prevent false sharing");
-ABSL_CONST_INIT absl::base_internal::AtomicHook<void (*)(int64_t wait_cycles)>
- submit_profile_data;
-ABSL_CONST_INIT absl::base_internal::AtomicHook<
- void (*)(const char *msg, const void *obj, int64_t wait_cycles)> mutex_tracer;
-ABSL_CONST_INIT absl::base_internal::AtomicHook<
- void (*)(const char *msg, const void *cv)> cond_var_tracer;
-ABSL_CONST_INIT absl::base_internal::AtomicHook<
+ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES
+ absl::base_internal::AtomicHook<void (*)(int64_t wait_cycles)>
+ submit_profile_data;
+ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES absl::base_internal::AtomicHook<void (*)(
+ const char *msg, const void *obj, int64_t wait_cycles)>
+ mutex_tracer;
+ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES
+ absl::base_internal::AtomicHook<void (*)(const char *msg, const void *cv)>
+ cond_var_tracer;
+ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES absl::base_internal::AtomicHook<
bool (*)(const void *pc, char *out, int out_size)>
symbolizer(absl::Symbolize);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-30 08:33:08 +0000