tvl-depot/absl/strings/cord.cc

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Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
// Copyright 2020 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/cord.h"
#include <algorithm>
#include <cstddef>
#include <cstdio>
#include <cstdlib>
#include <iomanip>
#include <limits>
#include <ostream>
#include <sstream>
#include <type_traits>
#include <unordered_set>
#include <vector>
#include "absl/base/casts.h"
#include "absl/base/internal/raw_logging.h"
Export of internal Abseil changes -- 2dd5008c7b4176859e320c7c337078adb173b662 by Tom Manshreck <shreck@google.com>: Internal change PiperOrigin-RevId: 304022549 -- 6442abd78697b03cfe698b0d0dac7f1eb4b5cb38 by Andy Getzendanner <durandal@google.com>: Internal change PiperOrigin-RevId: 303890410 -- eb8b37b468b0f23da09d3de714272928ef61f942 by Gennadiy Rozental <rogeeff@google.com>: Roll changes forward with ChunkIterator templatized. This should facilitate usage of "small" chunk iterator for a regular usage and proper "big" iterator internally in Cord implementation. This way Cord users are not exposed to stack size overhead if they have a lot of chunk iterators or recursive implementation which relies on chunk iterators. PiperOrigin-RevId: 303877118 -- 9623c569e7c55b45254e95f2d14c5badf9c901aa by Gennadiy Rozental <rogeeff@google.com>: Switch Flags implementation of fast type id to use absl/base/internal/fast_type_id.h PiperOrigin-RevId: 303861019 -- e2931e8d53c86d0816da6bbc8ba58cf5a3a443bb by Matthew Brown <matthewbr@google.com>: Internal Change PiperOrigin-RevId: 303832407 -- b549ed6e441e920b8ad6f02a80b9fd543820ef86 by Tom Manshreck <shreck@google.com>: Update Cord header file comments to Abseil standards PiperOrigin-RevId: 303823232 -- fc633d4f31a2d058f2b6a7029fc7c9820cd71c92 by Evan Brown <ezb@google.com>: Remove top-level const from K/V in map_slot_type::mutable_value and map_slot_type::key. This allows us to move between `map_slot_type::mutable_value`s internally even when the key_type and/or mapped_type specified by the user are const. PiperOrigin-RevId: 303811694 -- 909b3ce7cb3583ee9c374d36ff5f82bba02a1b64 by Derek Mauro <dmauro@google.com>: Add hardening assertions to the preconditions of absl::Cord PiperOrigin-RevId: 303419537 -- 9d32f79eabd54e6cb17bcc28b53e9bcfeb3cf6f4 by Greg Falcon <gfalcon@google.com>: Don't use MSVC-specific bit manipulations when using Clang on Windows. This fixes a compiler warning. Note that we do not have continuous testing for this configuration; this CL is best-effort support. PiperOrigin-RevId: 303322582 -- f6e0a35a2b9081d2a9eef73789b7bc1b5e46e5ad by Gennadiy Rozental <rogeeff@google.com>: Introduce standlone FastTypeId utility to represent compile time unique type id. PiperOrigin-RevId: 303180545 -- 99120e9fbdb5b2d327139ab8f617533d7bc3345b by Abseil Team <absl-team@google.com>: Changed absl's import of std::string_view to using string_view = std::string_view. This should help tools (e.g. include-what-you-use) discover where absl::string_view is defined. PiperOrigin-RevId: 303169095 GitOrigin-RevId: 2dd5008c7b4176859e320c7c337078adb173b662 Change-Id: I1e18ae08e23686ac963e7ea5e5bd499e18d51048
2020-03-31 21:32:35 +02:00
#include "absl/base/macros.h"
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
#include "absl/base/port.h"
#include "absl/container/fixed_array.h"
#include "absl/container/inlined_vector.h"
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
#include "absl/strings/escaping.h"
#include "absl/strings/internal/cord_internal.h"
#include "absl/strings/internal/resize_uninitialized.h"
#include "absl/strings/str_cat.h"
#include "absl/strings/str_format.h"
#include "absl/strings/str_join.h"
#include "absl/strings/string_view.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
using ::absl::cord_internal::CordRep;
using ::absl::cord_internal::CordRepConcat;
using ::absl::cord_internal::CordRepExternal;
using ::absl::cord_internal::CordRepSubstring;
// Various representations that we allow
enum CordRepKind {
CONCAT = 0,
EXTERNAL = 1,
SUBSTRING = 2,
// We have different tags for different sized flat arrays,
// starting with FLAT
FLAT = 3,
};
namespace {
// Type used with std::allocator for allocating and deallocating
// `CordRepExternal`. std::allocator is used because it opaquely handles the
// different new / delete overloads available on a given platform.
Export of internal Abseil changes -- 00f5301405423005d9129935c05f20155536cc1a by CJ Johnson <johnsoncj@google.com>: Removes usage of std::aligned_storage from Abseil implementation details PiperOrigin-RevId: 296492301 -- fc11d15f91764612fba080669d2381dc181df52b by Abseil Team <absl-team@google.com>: Fix absl::bind_front documentation. PiperOrigin-RevId: 296482945 -- 0164c595c129c46bf21ae74eba5399a1da5f140b by Gennadiy Rozental <rogeeff@google.com>: Automated g4 rollback of changelist 296320700. PiperOrigin-RevId: 296439968 -- 1eb295700758ca0894d872b2de7c675b4ad679af by Abseil Team <absl-team@google.com>: Removes duplicate comments. PiperOrigin-RevId: 296433214 -- c30c01caae02d2fa4ef783d988de6bebb9757c39 by Derek Mauro <dmauro@google.com>: Merge GitHub #621: Add RISCV support to GetProgramCounter() Fixes #621 PiperOrigin-RevId: 296351174 -- 95d4498167596fd7543e025bdfe9a8da9e2ca3c8 by Abseil Team <absl-team@google.com>: Automated g4 rollback of changelist 296320700. PiperOrigin-RevId: 296348701 -- b193f0543e0cec54dddb2ed51f45dc489c8d06d5 by Gennadiy Rozental <rogeeff@google.com>: Change TryParse interface to return managed value. In addition introduce companion StoreValue routine which consumes pointer to source value and stores the value inside of FlagImpl. In a follow up CL we will change StoreValue implementation to behave differently depending on "value storage kind". We also rename default_src_ to default_value_. PiperOrigin-RevId: 296320700 -- 57e942b485d12912a0a8d0d0b35fa2a62847020f by Derek Mauro <dmauro@google.com>: Merge GitHub #622 * Add missing #ifdef conditionals for ABSL_HAVE_VDSO_SUPPORT PiperOrigin-RevId: 296272830 GitOrigin-RevId: 00f5301405423005d9129935c05f20155536cc1a Change-Id: I1b05eeaf1280f95fb0a2c5f3654995a87c792893
2020-02-21 21:51:36 +01:00
struct alignas(absl::cord_internal::ExternalRepAlignment()) ExternalAllocType {
unsigned char value[absl::cord_internal::ExternalRepAlignment()];
};
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
// Returns the number of objects to pass in to std::allocator<ExternalAllocType>
// allocate() and deallocate() to create enough room for `CordRepExternal` with
// `releaser_size` bytes on the end.
constexpr size_t GetExternalAllocNumObjects(size_t releaser_size) {
// Be sure to round up since `releaser_size` could be smaller than
Export of internal Abseil changes -- 00f5301405423005d9129935c05f20155536cc1a by CJ Johnson <johnsoncj@google.com>: Removes usage of std::aligned_storage from Abseil implementation details PiperOrigin-RevId: 296492301 -- fc11d15f91764612fba080669d2381dc181df52b by Abseil Team <absl-team@google.com>: Fix absl::bind_front documentation. PiperOrigin-RevId: 296482945 -- 0164c595c129c46bf21ae74eba5399a1da5f140b by Gennadiy Rozental <rogeeff@google.com>: Automated g4 rollback of changelist 296320700. PiperOrigin-RevId: 296439968 -- 1eb295700758ca0894d872b2de7c675b4ad679af by Abseil Team <absl-team@google.com>: Removes duplicate comments. PiperOrigin-RevId: 296433214 -- c30c01caae02d2fa4ef783d988de6bebb9757c39 by Derek Mauro <dmauro@google.com>: Merge GitHub #621: Add RISCV support to GetProgramCounter() Fixes #621 PiperOrigin-RevId: 296351174 -- 95d4498167596fd7543e025bdfe9a8da9e2ca3c8 by Abseil Team <absl-team@google.com>: Automated g4 rollback of changelist 296320700. PiperOrigin-RevId: 296348701 -- b193f0543e0cec54dddb2ed51f45dc489c8d06d5 by Gennadiy Rozental <rogeeff@google.com>: Change TryParse interface to return managed value. In addition introduce companion StoreValue routine which consumes pointer to source value and stores the value inside of FlagImpl. In a follow up CL we will change StoreValue implementation to behave differently depending on "value storage kind". We also rename default_src_ to default_value_. PiperOrigin-RevId: 296320700 -- 57e942b485d12912a0a8d0d0b35fa2a62847020f by Derek Mauro <dmauro@google.com>: Merge GitHub #622 * Add missing #ifdef conditionals for ABSL_HAVE_VDSO_SUPPORT PiperOrigin-RevId: 296272830 GitOrigin-RevId: 00f5301405423005d9129935c05f20155536cc1a Change-Id: I1b05eeaf1280f95fb0a2c5f3654995a87c792893
2020-02-21 21:51:36 +01:00
// `sizeof(ExternalAllocType)`.
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
return (sizeof(CordRepExternal) + releaser_size + sizeof(ExternalAllocType) -
1) /
sizeof(ExternalAllocType);
}
// Allocates enough memory for `CordRepExternal` and a releaser with size
// `releaser_size` bytes.
void* AllocateExternal(size_t releaser_size) {
return std::allocator<ExternalAllocType>().allocate(
GetExternalAllocNumObjects(releaser_size));
}
// Deallocates the memory for a `CordRepExternal` assuming it was allocated with
// a releaser of given size and alignment.
void DeallocateExternal(CordRepExternal* p, size_t releaser_size) {
std::allocator<ExternalAllocType>().deallocate(
reinterpret_cast<ExternalAllocType*>(p),
GetExternalAllocNumObjects(releaser_size));
}
// Returns a pointer to the type erased releaser for the given CordRepExternal.
void* GetExternalReleaser(CordRepExternal* rep) {
return rep + 1;
}
} // namespace
namespace cord_internal {
inline CordRepConcat* CordRep::concat() {
assert(tag == CONCAT);
return static_cast<CordRepConcat*>(this);
}
inline const CordRepConcat* CordRep::concat() const {
assert(tag == CONCAT);
return static_cast<const CordRepConcat*>(this);
}
inline CordRepSubstring* CordRep::substring() {
assert(tag == SUBSTRING);
return static_cast<CordRepSubstring*>(this);
}
inline const CordRepSubstring* CordRep::substring() const {
assert(tag == SUBSTRING);
return static_cast<const CordRepSubstring*>(this);
}
inline CordRepExternal* CordRep::external() {
assert(tag == EXTERNAL);
return static_cast<CordRepExternal*>(this);
}
inline const CordRepExternal* CordRep::external() const {
assert(tag == EXTERNAL);
return static_cast<const CordRepExternal*>(this);
}
} // namespace cord_internal
static const size_t kFlatOverhead = offsetof(CordRep, data);
// Largest and smallest flat node lengths we are willing to allocate
// Flat allocation size is stored in tag, which currently can encode sizes up
// to 4K, encoded as multiple of either 8 or 32 bytes.
// If we allow for larger sizes, we need to change this to 8/64, 16/128, etc.
static constexpr size_t kMaxFlatSize = 4096;
static constexpr size_t kMaxFlatLength = kMaxFlatSize - kFlatOverhead;
static constexpr size_t kMinFlatLength = 32 - kFlatOverhead;
// Prefer copying blocks of at most this size, otherwise reference count.
static const size_t kMaxBytesToCopy = 511;
// Helper functions for rounded div, and rounding to exact sizes.
static size_t DivUp(size_t n, size_t m) { return (n + m - 1) / m; }
static size_t RoundUp(size_t n, size_t m) { return DivUp(n, m) * m; }
// Returns the size to the nearest equal or larger value that can be
// expressed exactly as a tag value.
static size_t RoundUpForTag(size_t size) {
return RoundUp(size, (size <= 1024) ? 8 : 32);
}
// Converts the allocated size to a tag, rounding down if the size
// does not exactly match a 'tag expressible' size value. The result is
// undefined if the size exceeds the maximum size that can be encoded in
// a tag, i.e., if size is larger than TagToAllocatedSize(<max tag>).
static uint8_t AllocatedSizeToTag(size_t size) {
const size_t tag = (size <= 1024) ? size / 8 : 128 + size / 32 - 1024 / 32;
assert(tag <= std::numeric_limits<uint8_t>::max());
return tag;
}
// Converts the provided tag to the corresponding allocated size
static constexpr size_t TagToAllocatedSize(uint8_t tag) {
return (tag <= 128) ? (tag * 8) : (1024 + (tag - 128) * 32);
}
// Converts the provided tag to the corresponding available data length
static constexpr size_t TagToLength(uint8_t tag) {
return TagToAllocatedSize(tag) - kFlatOverhead;
}
// Enforce that kMaxFlatSize maps to a well-known exact tag value.
static_assert(TagToAllocatedSize(224) == kMaxFlatSize, "Bad tag logic");
constexpr uint64_t Fibonacci(unsigned char n, uint64_t a = 0, uint64_t b = 1) {
return n == 0 ? a : Fibonacci(n - 1, b, a + b);
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
}
static_assert(Fibonacci(63) == 6557470319842,
"Fibonacci values computed incorrectly");
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
// Minimum length required for a given depth tree -- a tree is considered
// balanced if
// length(t) >= min_length[depth(t)]
// The root node depth is allowed to become twice as large to reduce rebalancing
// for larger strings (see IsRootBalanced).
static constexpr uint64_t min_length[] = {
Fibonacci(2), Fibonacci(3), Fibonacci(4), Fibonacci(5),
Fibonacci(6), Fibonacci(7), Fibonacci(8), Fibonacci(9),
Fibonacci(10), Fibonacci(11), Fibonacci(12), Fibonacci(13),
Fibonacci(14), Fibonacci(15), Fibonacci(16), Fibonacci(17),
Fibonacci(18), Fibonacci(19), Fibonacci(20), Fibonacci(21),
Fibonacci(22), Fibonacci(23), Fibonacci(24), Fibonacci(25),
Fibonacci(26), Fibonacci(27), Fibonacci(28), Fibonacci(29),
Fibonacci(30), Fibonacci(31), Fibonacci(32), Fibonacci(33),
Fibonacci(34), Fibonacci(35), Fibonacci(36), Fibonacci(37),
Fibonacci(38), Fibonacci(39), Fibonacci(40), Fibonacci(41),
Fibonacci(42), Fibonacci(43), Fibonacci(44), Fibonacci(45),
Fibonacci(46), Fibonacci(47),
0xffffffffffffffffull, // Avoid overflow
};
static const int kMinLengthSize = ABSL_ARRAYSIZE(min_length);
// The inlined size to use with absl::InlinedVector.
//
// Note: The InlinedVectors in this file (and in cord.h) do not need to use
// the same value for their inlined size. The fact that they do is historical.
// It may be desirable for each to use a different inlined size optimized for
// that InlinedVector's usage.
//
// TODO(jgm): Benchmark to see if there's a more optimal value than 47 for
// the inlined vector size (47 exists for backward compatibility).
static const int kInlinedVectorSize = 47;
static inline bool IsRootBalanced(CordRep* node) {
if (node->tag != CONCAT) {
return true;
} else if (node->concat()->depth() <= 15) {
return true;
} else if (node->concat()->depth() > kMinLengthSize) {
return false;
} else {
// Allow depth to become twice as large as implied by fibonacci rule to
// reduce rebalancing for larger strings.
return (node->length >= min_length[node->concat()->depth() / 2]);
}
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
}
static CordRep* Rebalance(CordRep* node);
static void DumpNode(CordRep* rep, bool include_data, std::ostream* os);
static bool VerifyNode(CordRep* root, CordRep* start_node,
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
bool full_validation);
static inline CordRep* VerifyTree(CordRep* node) {
// Verification is expensive, so only do it in debug mode.
// Even in debug mode we normally do only light validation.
// If you are debugging Cord itself, you should define the
// macro EXTRA_CORD_VALIDATION, e.g. by adding
// --copt=-DEXTRA_CORD_VALIDATION to the blaze line.
#ifdef EXTRA_CORD_VALIDATION
assert(node == nullptr || VerifyNode(node, node, /*full_validation=*/true));
#else // EXTRA_CORD_VALIDATION
assert(node == nullptr || VerifyNode(node, node, /*full_validation=*/false));
#endif // EXTRA_CORD_VALIDATION
static_cast<void>(&VerifyNode);
return node;
}
// --------------------------------------------------------------------
// Memory management
inline CordRep* Ref(CordRep* rep) {
if (rep != nullptr) {
rep->refcount.Increment();
}
return rep;
}
// This internal routine is called from the cold path of Unref below. Keeping it
// in a separate routine allows good inlining of Unref into many profitable call
// sites. However, the call to this function can be highly disruptive to the
// register pressure in those callers. To minimize the cost to callers, we use
// a special LLVM calling convention that preserves most registers. This allows
// the call to this routine in cold paths to not disrupt the caller's register
// pressure. This calling convention is not available on all platforms; we
// intentionally allow LLVM to ignore the attribute rather than attempting to
// hardcode the list of supported platforms.
#if defined(__clang__) && !defined(__i386__)
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wattributes"
__attribute__((preserve_most))
#pragma clang diagnostic pop
#endif
static void UnrefInternal(CordRep* rep) {
assert(rep != nullptr);
absl::InlinedVector<CordRep*, kInlinedVectorSize> pending;
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
while (true) {
if (rep->tag == CONCAT) {
CordRepConcat* rep_concat = rep->concat();
CordRep* right = rep_concat->right;
if (!right->refcount.Decrement()) {
pending.push_back(right);
}
CordRep* left = rep_concat->left;
delete rep_concat;
rep = nullptr;
if (!left->refcount.Decrement()) {
rep = left;
continue;
}
} else if (rep->tag == EXTERNAL) {
CordRepExternal* rep_external = rep->external();
absl::string_view data(rep_external->base, rep->length);
void* releaser = GetExternalReleaser(rep_external);
size_t releaser_size = rep_external->releaser_invoker(releaser, data);
rep_external->~CordRepExternal();
DeallocateExternal(rep_external, releaser_size);
rep = nullptr;
} else if (rep->tag == SUBSTRING) {
CordRepSubstring* rep_substring = rep->substring();
CordRep* child = rep_substring->child;
delete rep_substring;
rep = nullptr;
if (!child->refcount.Decrement()) {
rep = child;
continue;
}
} else {
// Flat CordReps are allocated and constructed with raw ::operator new
// and placement new, and must be destructed and deallocated
// accordingly.
#if defined(__cpp_sized_deallocation)
size_t size = TagToAllocatedSize(rep->tag);
rep->~CordRep();
::operator delete(rep, size);
#else
rep->~CordRep();
::operator delete(rep);
#endif
rep = nullptr;
}
if (!pending.empty()) {
rep = pending.back();
pending.pop_back();
} else {
break;
}
}
}
inline void Unref(CordRep* rep) {
// Fast-path for two common, hot cases: a null rep and a shared root.
if (ABSL_PREDICT_TRUE(rep == nullptr ||
rep->refcount.DecrementExpectHighRefcount())) {
return;
}
UnrefInternal(rep);
}
// Return the depth of a node
static int Depth(const CordRep* rep) {
if (rep->tag == CONCAT) {
return rep->concat()->depth();
} else {
return 0;
}
}
static void SetConcatChildren(CordRepConcat* concat, CordRep* left,
CordRep* right) {
concat->left = left;
concat->right = right;
concat->length = left->length + right->length;
concat->set_depth(1 + std::max(Depth(left), Depth(right)));
}
// Create a concatenation of the specified nodes.
// Does not change the refcounts of "left" and "right".
// The returned node has a refcount of 1.
static CordRep* RawConcat(CordRep* left, CordRep* right) {
// Avoid making degenerate concat nodes (one child is empty)
if (left == nullptr || left->length == 0) {
Unref(left);
return right;
}
if (right == nullptr || right->length == 0) {
Unref(right);
return left;
}
CordRepConcat* rep = new CordRepConcat();
rep->tag = CONCAT;
SetConcatChildren(rep, left, right);
return rep;
}
static CordRep* Concat(CordRep* left, CordRep* right) {
CordRep* rep = RawConcat(left, right);
if (rep != nullptr && !IsRootBalanced(rep)) {
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
rep = Rebalance(rep);
}
return VerifyTree(rep);
}
// Make a balanced tree out of an array of leaf nodes.
static CordRep* MakeBalancedTree(CordRep** reps, size_t n) {
// Make repeated passes over the array, merging adjacent pairs
// until we are left with just a single node.
while (n > 1) {
size_t dst = 0;
for (size_t src = 0; src < n; src += 2) {
if (src + 1 < n) {
reps[dst] = Concat(reps[src], reps[src + 1]);
} else {
reps[dst] = reps[src];
}
dst++;
}
n = dst;
}
return reps[0];
}
// Create a new flat node.
static CordRep* NewFlat(size_t length_hint) {
if (length_hint <= kMinFlatLength) {
length_hint = kMinFlatLength;
} else if (length_hint > kMaxFlatLength) {
length_hint = kMaxFlatLength;
}
// Round size up so it matches a size we can exactly express in a tag.
const size_t size = RoundUpForTag(length_hint + kFlatOverhead);
void* const raw_rep = ::operator new(size);
CordRep* rep = new (raw_rep) CordRep();
rep->tag = AllocatedSizeToTag(size);
return VerifyTree(rep);
}
// Create a new tree out of the specified array.
// The returned node has a refcount of 1.
static CordRep* NewTree(const char* data,
size_t length,
size_t alloc_hint) {
if (length == 0) return nullptr;
absl::FixedArray<CordRep*> reps((length - 1) / kMaxFlatLength + 1);
size_t n = 0;
do {
const size_t len = std::min(length, kMaxFlatLength);
CordRep* rep = NewFlat(len + alloc_hint);
rep->length = len;
memcpy(rep->data, data, len);
reps[n++] = VerifyTree(rep);
data += len;
length -= len;
} while (length != 0);
return MakeBalancedTree(reps.data(), n);
}
namespace cord_internal {
ExternalRepReleaserPair NewExternalWithUninitializedReleaser(
absl::string_view data, ExternalReleaserInvoker invoker,
size_t releaser_size) {
assert(!data.empty());
void* raw_rep = AllocateExternal(releaser_size);
auto* rep = new (raw_rep) CordRepExternal();
rep->length = data.size();
rep->tag = EXTERNAL;
rep->base = data.data();
rep->releaser_invoker = invoker;
return {VerifyTree(rep), GetExternalReleaser(rep)};
}
} // namespace cord_internal
static CordRep* NewSubstring(CordRep* child, size_t offset, size_t length) {
// Never create empty substring nodes
if (length == 0) {
Unref(child);
return nullptr;
} else {
CordRepSubstring* rep = new CordRepSubstring();
assert((offset + length) <= child->length);
rep->length = length;
rep->tag = SUBSTRING;
rep->start = offset;
rep->child = child;
return VerifyTree(rep);
}
}
// --------------------------------------------------------------------
// Cord::InlineRep functions
// This will trigger LNK2005 in MSVC.
#ifndef COMPILER_MSVC
const unsigned char Cord::InlineRep::kMaxInline;
#endif // COMPILER_MSVC
inline void Cord::InlineRep::set_data(const char* data, size_t n,
bool nullify_tail) {
static_assert(kMaxInline == 15, "set_data is hard-coded for a length of 15");
cord_internal::SmallMemmove(data_, data, n, nullify_tail);
data_[kMaxInline] = static_cast<char>(n);
}
inline char* Cord::InlineRep::set_data(size_t n) {
assert(n <= kMaxInline);
memset(data_, 0, sizeof(data_));
data_[kMaxInline] = static_cast<char>(n);
return data_;
}
inline CordRep* Cord::InlineRep::force_tree(size_t extra_hint) {
size_t len = data_[kMaxInline];
CordRep* result;
if (len > kMaxInline) {
memcpy(&result, data_, sizeof(result));
} else {
result = NewFlat(len + extra_hint);
result->length = len;
memcpy(result->data, data_, len);
set_tree(result);
}
return result;
}
inline void Cord::InlineRep::reduce_size(size_t n) {
size_t tag = data_[kMaxInline];
assert(tag <= kMaxInline);
assert(tag >= n);
tag -= n;
memset(data_ + tag, 0, n);
data_[kMaxInline] = static_cast<char>(tag);
}
inline void Cord::InlineRep::remove_prefix(size_t n) {
cord_internal::SmallMemmove(data_, data_ + n, data_[kMaxInline] - n);
reduce_size(n);
}
void Cord::InlineRep::AppendTree(CordRep* tree) {
if (tree == nullptr) return;
size_t len = data_[kMaxInline];
if (len == 0) {
set_tree(tree);
} else {
set_tree(Concat(force_tree(0), tree));
}
}
void Cord::InlineRep::PrependTree(CordRep* tree) {
if (tree == nullptr) return;
size_t len = data_[kMaxInline];
if (len == 0) {
set_tree(tree);
} else {
set_tree(Concat(tree, force_tree(0)));
}
}
// Searches for a non-full flat node at the rightmost leaf of the tree. If a
// suitable leaf is found, the function will update the length field for all
// nodes to account for the size increase. The append region address will be
// written to region and the actual size increase will be written to size.
static inline bool PrepareAppendRegion(CordRep* root, char** region,
size_t* size, size_t max_length) {
// Search down the right-hand path for a non-full FLAT node.
CordRep* dst = root;
while (dst->tag == CONCAT && dst->refcount.IsOne()) {
dst = dst->concat()->right;
}
if (dst->tag < FLAT || !dst->refcount.IsOne()) {
*region = nullptr;
*size = 0;
return false;
}
const size_t in_use = dst->length;
const size_t capacity = TagToLength(dst->tag);
if (in_use == capacity) {
*region = nullptr;
*size = 0;
return false;
}
size_t size_increase = std::min(capacity - in_use, max_length);
// We need to update the length fields for all nodes, including the leaf node.
for (CordRep* rep = root; rep != dst; rep = rep->concat()->right) {
rep->length += size_increase;
}
dst->length += size_increase;
*region = dst->data + in_use;
*size = size_increase;
return true;
}
void Cord::InlineRep::GetAppendRegion(char** region, size_t* size,
size_t max_length) {
if (max_length == 0) {
*region = nullptr;
*size = 0;
return;
}
// Try to fit in the inline buffer if possible.
size_t inline_length = data_[kMaxInline];
if (inline_length < kMaxInline && max_length <= kMaxInline - inline_length) {
*region = data_ + inline_length;
*size = max_length;
data_[kMaxInline] = static_cast<char>(inline_length + max_length);
return;
}
CordRep* root = force_tree(max_length);
if (PrepareAppendRegion(root, region, size, max_length)) {
return;
}
// Allocate new node.
CordRep* new_node =
NewFlat(std::max(static_cast<size_t>(root->length), max_length));
new_node->length =
std::min(static_cast<size_t>(TagToLength(new_node->tag)), max_length);
*region = new_node->data;
*size = new_node->length;
replace_tree(Concat(root, new_node));
}
void Cord::InlineRep::GetAppendRegion(char** region, size_t* size) {
const size_t max_length = std::numeric_limits<size_t>::max();
// Try to fit in the inline buffer if possible.
size_t inline_length = data_[kMaxInline];
if (inline_length < kMaxInline) {
*region = data_ + inline_length;
*size = kMaxInline - inline_length;
data_[kMaxInline] = kMaxInline;
return;
}
CordRep* root = force_tree(max_length);
if (PrepareAppendRegion(root, region, size, max_length)) {
return;
}
// Allocate new node.
CordRep* new_node = NewFlat(root->length);
new_node->length = TagToLength(new_node->tag);
*region = new_node->data;
*size = new_node->length;
replace_tree(Concat(root, new_node));
}
// If the rep is a leaf, this will increment the value at total_mem_usage and
// will return true.
static bool RepMemoryUsageLeaf(const CordRep* rep, size_t* total_mem_usage) {
if (rep->tag >= FLAT) {
*total_mem_usage += TagToAllocatedSize(rep->tag);
return true;
}
if (rep->tag == EXTERNAL) {
*total_mem_usage += sizeof(CordRepConcat) + rep->length;
return true;
}
return false;
}
void Cord::InlineRep::AssignSlow(const Cord::InlineRep& src) {
ClearSlow();
memcpy(data_, src.data_, sizeof(data_));
if (is_tree()) {
Ref(tree());
}
}
void Cord::InlineRep::ClearSlow() {
if (is_tree()) {
Unref(tree());
}
memset(data_, 0, sizeof(data_));
}
// --------------------------------------------------------------------
// Constructors and destructors
Cord::Cord(const Cord& src) : contents_(src.contents_) {
Ref(contents_.tree()); // Does nothing if contents_ has embedded data
}
Cord::Cord(absl::string_view src) {
const size_t n = src.size();
if (n <= InlineRep::kMaxInline) {
contents_.set_data(src.data(), n, false);
} else {
contents_.set_tree(NewTree(src.data(), n, 0));
}
}
// The destruction code is separate so that the compiler can determine
// that it does not need to call the destructor on a moved-from Cord.
void Cord::DestroyCordSlow() {
Unref(VerifyTree(contents_.tree()));
}
// --------------------------------------------------------------------
// Mutators
void Cord::Clear() {
Unref(contents_.clear());
}
Cord& Cord::operator=(absl::string_view src) {
const char* data = src.data();
size_t length = src.size();
CordRep* tree = contents_.tree();
if (length <= InlineRep::kMaxInline) {
// Embed into this->contents_
contents_.set_data(data, length, true);
Unref(tree);
return *this;
}
if (tree != nullptr && tree->tag >= FLAT &&
TagToLength(tree->tag) >= length && tree->refcount.IsOne()) {
// Copy in place if the existing FLAT node is reusable.
memmove(tree->data, data, length);
tree->length = length;
VerifyTree(tree);
return *this;
}
contents_.set_tree(NewTree(data, length, 0));
Unref(tree);
return *this;
}
// TODO(sanjay): Move to Cord::InlineRep section of file. For now,
// we keep it here to make diffs easier.
void Cord::InlineRep::AppendArray(const char* src_data, size_t src_size) {
if (src_size == 0) return; // memcpy(_, nullptr, 0) is undefined.
// Try to fit in the inline buffer if possible.
size_t inline_length = data_[kMaxInline];
if (inline_length < kMaxInline && src_size <= kMaxInline - inline_length) {
// Append new data to embedded array
data_[kMaxInline] = static_cast<char>(inline_length + src_size);
memcpy(data_ + inline_length, src_data, src_size);
return;
}
CordRep* root = tree();
size_t appended = 0;
if (root) {
char* region;
if (PrepareAppendRegion(root, &region, &appended, src_size)) {
memcpy(region, src_data, appended);
}
} else {
// It is possible that src_data == data_, but when we transition from an
// InlineRep to a tree we need to assign data_ = root via set_tree. To
// avoid corrupting the source data before we copy it, delay calling
// set_tree until after we've copied data.
// We are going from an inline size to beyond inline size. Make the new size
// either double the inlined size, or the added size + 10%.
const size_t size1 = inline_length * 2 + src_size;
const size_t size2 = inline_length + src_size / 10;
root = NewFlat(std::max<size_t>(size1, size2));
appended = std::min(src_size, TagToLength(root->tag) - inline_length);
memcpy(root->data, data_, inline_length);
memcpy(root->data + inline_length, src_data, appended);
root->length = inline_length + appended;
set_tree(root);
}
src_data += appended;
src_size -= appended;
if (src_size == 0) {
return;
}
// Use new block(s) for any remaining bytes that were not handled above.
// Alloc extra memory only if the right child of the root of the new tree is
// going to be a FLAT node, which will permit further inplace appends.
size_t length = src_size;
if (src_size < kMaxFlatLength) {
// The new length is either
// - old size + 10%
// - old_size + src_size
// This will cause a reasonable conservative step-up in size that is still
// large enough to avoid excessive amounts of small fragments being added.
length = std::max<size_t>(root->length / 10, src_size);
}
set_tree(Concat(root, NewTree(src_data, src_size, length - src_size)));
}
inline CordRep* Cord::TakeRep() const& {
return Ref(contents_.tree());
}
inline CordRep* Cord::TakeRep() && {
CordRep* rep = contents_.tree();
contents_.clear();
return rep;
}
template <typename C>
inline void Cord::AppendImpl(C&& src) {
if (empty()) {
// In case of an empty destination avoid allocating a new node, do not copy
// data.
*this = std::forward<C>(src);
return;
}
// For short cords, it is faster to copy data if there is room in dst.
const size_t src_size = src.contents_.size();
if (src_size <= kMaxBytesToCopy) {
CordRep* src_tree = src.contents_.tree();
if (src_tree == nullptr) {
// src has embedded data.
contents_.AppendArray(src.contents_.data(), src_size);
return;
}
if (src_tree->tag >= FLAT) {
// src tree just has one flat node.
contents_.AppendArray(src_tree->data, src_size);
return;
}
if (&src == this) {
// ChunkIterator below assumes that src is not modified during traversal.
Append(Cord(src));
return;
}
// TODO(mec): Should we only do this if "dst" has space?
for (absl::string_view chunk : src.Chunks()) {
Append(chunk);
}
return;
}
contents_.AppendTree(std::forward<C>(src).TakeRep());
}
void Cord::Append(const Cord& src) { AppendImpl(src); }
void Cord::Append(Cord&& src) { AppendImpl(std::move(src)); }
void Cord::Prepend(const Cord& src) {
CordRep* src_tree = src.contents_.tree();
if (src_tree != nullptr) {
Ref(src_tree);
contents_.PrependTree(src_tree);
return;
}
// `src` cord is inlined.
absl::string_view src_contents(src.contents_.data(), src.contents_.size());
return Prepend(src_contents);
}
void Cord::Prepend(absl::string_view src) {
if (src.empty()) return; // memcpy(_, nullptr, 0) is undefined.
size_t cur_size = contents_.size();
if (!contents_.is_tree() && cur_size + src.size() <= InlineRep::kMaxInline) {
// Use embedded storage.
char data[InlineRep::kMaxInline + 1] = {0};
data[InlineRep::kMaxInline] = cur_size + src.size(); // set size
memcpy(data, src.data(), src.size());
memcpy(data + src.size(), contents_.data(), cur_size);
memcpy(reinterpret_cast<void*>(&contents_), data,
InlineRep::kMaxInline + 1);
} else {
contents_.PrependTree(NewTree(src.data(), src.size(), 0));
}
}
static CordRep* RemovePrefixFrom(CordRep* node, size_t n) {
if (n >= node->length) return nullptr;
if (n == 0) return Ref(node);
absl::InlinedVector<CordRep*, kInlinedVectorSize> rhs_stack;
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
while (node->tag == CONCAT) {
assert(n <= node->length);
if (n < node->concat()->left->length) {
// Push right to stack, descend left.
rhs_stack.push_back(node->concat()->right);
node = node->concat()->left;
} else {
// Drop left, descend right.
n -= node->concat()->left->length;
node = node->concat()->right;
}
}
assert(n <= node->length);
if (n == 0) {
Ref(node);
} else {
size_t start = n;
size_t len = node->length - n;
if (node->tag == SUBSTRING) {
// Consider in-place update of node, similar to in RemoveSuffixFrom().
start += node->substring()->start;
node = node->substring()->child;
}
node = NewSubstring(Ref(node), start, len);
}
while (!rhs_stack.empty()) {
node = Concat(node, Ref(rhs_stack.back()));
rhs_stack.pop_back();
}
return node;
}
// RemoveSuffixFrom() is very similar to RemovePrefixFrom(), with the
// exception that removing a suffix has an optimization where a node may be
// edited in place iff that node and all its ancestors have a refcount of 1.
static CordRep* RemoveSuffixFrom(CordRep* node, size_t n) {
if (n >= node->length) return nullptr;
if (n == 0) return Ref(node);
absl::InlinedVector<CordRep*, kInlinedVectorSize> lhs_stack;
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
bool inplace_ok = node->refcount.IsOne();
while (node->tag == CONCAT) {
assert(n <= node->length);
if (n < node->concat()->right->length) {
// Push left to stack, descend right.
lhs_stack.push_back(node->concat()->left);
node = node->concat()->right;
} else {
// Drop right, descend left.
n -= node->concat()->right->length;
node = node->concat()->left;
}
inplace_ok = inplace_ok && node->refcount.IsOne();
}
assert(n <= node->length);
if (n == 0) {
Ref(node);
} else if (inplace_ok && node->tag != EXTERNAL) {
// Consider making a new buffer if the current node capacity is much
// larger than the new length.
Ref(node);
node->length -= n;
} else {
size_t start = 0;
size_t len = node->length - n;
if (node->tag == SUBSTRING) {
start = node->substring()->start;
node = node->substring()->child;
}
node = NewSubstring(Ref(node), start, len);
}
while (!lhs_stack.empty()) {
node = Concat(Ref(lhs_stack.back()), node);
lhs_stack.pop_back();
}
return node;
}
void Cord::RemovePrefix(size_t n) {
ABSL_INTERNAL_CHECK(n <= size(),
absl::StrCat("Requested prefix size ", n,
" exceeds Cord's size ", size()));
CordRep* tree = contents_.tree();
if (tree == nullptr) {
contents_.remove_prefix(n);
} else {
CordRep* newrep = RemovePrefixFrom(tree, n);
Unref(tree);
contents_.replace_tree(VerifyTree(newrep));
}
}
void Cord::RemoveSuffix(size_t n) {
ABSL_INTERNAL_CHECK(n <= size(),
absl::StrCat("Requested suffix size ", n,
" exceeds Cord's size ", size()));
CordRep* tree = contents_.tree();
if (tree == nullptr) {
contents_.reduce_size(n);
} else {
CordRep* newrep = RemoveSuffixFrom(tree, n);
Unref(tree);
contents_.replace_tree(VerifyTree(newrep));
}
}
// Work item for NewSubRange().
struct SubRange {
SubRange(CordRep* a_node, size_t a_pos, size_t a_n)
: node(a_node), pos(a_pos), n(a_n) {}
CordRep* node; // nullptr means concat last 2 results.
size_t pos;
size_t n;
};
static CordRep* NewSubRange(CordRep* node, size_t pos, size_t n) {
absl::InlinedVector<CordRep*, kInlinedVectorSize> results;
absl::InlinedVector<SubRange, kInlinedVectorSize> todo;
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
todo.push_back(SubRange(node, pos, n));
do {
const SubRange& sr = todo.back();
node = sr.node;
pos = sr.pos;
n = sr.n;
todo.pop_back();
if (node == nullptr) {
assert(results.size() >= 2);
CordRep* right = results.back();
results.pop_back();
CordRep* left = results.back();
results.pop_back();
results.push_back(Concat(left, right));
} else if (pos == 0 && n == node->length) {
results.push_back(Ref(node));
} else if (node->tag != CONCAT) {
if (node->tag == SUBSTRING) {
pos += node->substring()->start;
node = node->substring()->child;
}
results.push_back(NewSubstring(Ref(node), pos, n));
} else if (pos + n <= node->concat()->left->length) {
todo.push_back(SubRange(node->concat()->left, pos, n));
} else if (pos >= node->concat()->left->length) {
pos -= node->concat()->left->length;
todo.push_back(SubRange(node->concat()->right, pos, n));
} else {
size_t left_n = node->concat()->left->length - pos;
todo.push_back(SubRange(nullptr, 0, 0)); // Concat()
todo.push_back(SubRange(node->concat()->right, 0, n - left_n));
todo.push_back(SubRange(node->concat()->left, pos, left_n));
}
} while (!todo.empty());
assert(results.size() == 1);
return results[0];
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
}
Cord Cord::Subcord(size_t pos, size_t new_size) const {
Cord sub_cord;
size_t length = size();
if (pos > length) pos = length;
if (new_size > length - pos) new_size = length - pos;
CordRep* tree = contents_.tree();
if (tree == nullptr) {
// sub_cord is newly constructed, no need to re-zero-out the tail of
// contents_ memory.
sub_cord.contents_.set_data(contents_.data() + pos, new_size, false);
} else if (new_size == 0) {
// We want to return empty subcord, so nothing to do.
} else if (new_size <= InlineRep::kMaxInline) {
Cord::ChunkIterator it = chunk_begin();
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
it.AdvanceBytes(pos);
char* dest = sub_cord.contents_.data_;
size_t remaining_size = new_size;
while (remaining_size > it->size()) {
cord_internal::SmallMemmove(dest, it->data(), it->size());
remaining_size -= it->size();
dest += it->size();
++it;
}
cord_internal::SmallMemmove(dest, it->data(), remaining_size);
sub_cord.contents_.data_[InlineRep::kMaxInline] = new_size;
} else {
sub_cord.contents_.set_tree(NewSubRange(tree, pos, new_size));
}
return sub_cord;
}
// --------------------------------------------------------------------
// Balancing
class CordForest {
public:
explicit CordForest(size_t length)
: root_length_(length), trees_(kMinLengthSize, nullptr) {}
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
void Build(CordRep* cord_root) {
std::vector<CordRep*> pending = {cord_root};
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
while (!pending.empty()) {
CordRep* node = pending.back();
pending.pop_back();
CheckNode(node);
if (ABSL_PREDICT_FALSE(node->tag != CONCAT)) {
AddNode(node);
continue;
}
CordRepConcat* concat_node = node->concat();
if (concat_node->depth() >= kMinLengthSize ||
concat_node->length < min_length[concat_node->depth()]) {
pending.push_back(concat_node->right);
pending.push_back(concat_node->left);
if (concat_node->refcount.IsOne()) {
concat_node->left = concat_freelist_;
concat_freelist_ = concat_node;
} else {
Ref(concat_node->right);
Ref(concat_node->left);
Unref(concat_node);
}
Export of internal Abseil changes -- 2dd5008c7b4176859e320c7c337078adb173b662 by Tom Manshreck <shreck@google.com>: Internal change PiperOrigin-RevId: 304022549 -- 6442abd78697b03cfe698b0d0dac7f1eb4b5cb38 by Andy Getzendanner <durandal@google.com>: Internal change PiperOrigin-RevId: 303890410 -- eb8b37b468b0f23da09d3de714272928ef61f942 by Gennadiy Rozental <rogeeff@google.com>: Roll changes forward with ChunkIterator templatized. This should facilitate usage of "small" chunk iterator for a regular usage and proper "big" iterator internally in Cord implementation. This way Cord users are not exposed to stack size overhead if they have a lot of chunk iterators or recursive implementation which relies on chunk iterators. PiperOrigin-RevId: 303877118 -- 9623c569e7c55b45254e95f2d14c5badf9c901aa by Gennadiy Rozental <rogeeff@google.com>: Switch Flags implementation of fast type id to use absl/base/internal/fast_type_id.h PiperOrigin-RevId: 303861019 -- e2931e8d53c86d0816da6bbc8ba58cf5a3a443bb by Matthew Brown <matthewbr@google.com>: Internal Change PiperOrigin-RevId: 303832407 -- b549ed6e441e920b8ad6f02a80b9fd543820ef86 by Tom Manshreck <shreck@google.com>: Update Cord header file comments to Abseil standards PiperOrigin-RevId: 303823232 -- fc633d4f31a2d058f2b6a7029fc7c9820cd71c92 by Evan Brown <ezb@google.com>: Remove top-level const from K/V in map_slot_type::mutable_value and map_slot_type::key. This allows us to move between `map_slot_type::mutable_value`s internally even when the key_type and/or mapped_type specified by the user are const. PiperOrigin-RevId: 303811694 -- 909b3ce7cb3583ee9c374d36ff5f82bba02a1b64 by Derek Mauro <dmauro@google.com>: Add hardening assertions to the preconditions of absl::Cord PiperOrigin-RevId: 303419537 -- 9d32f79eabd54e6cb17bcc28b53e9bcfeb3cf6f4 by Greg Falcon <gfalcon@google.com>: Don't use MSVC-specific bit manipulations when using Clang on Windows. This fixes a compiler warning. Note that we do not have continuous testing for this configuration; this CL is best-effort support. PiperOrigin-RevId: 303322582 -- f6e0a35a2b9081d2a9eef73789b7bc1b5e46e5ad by Gennadiy Rozental <rogeeff@google.com>: Introduce standlone FastTypeId utility to represent compile time unique type id. PiperOrigin-RevId: 303180545 -- 99120e9fbdb5b2d327139ab8f617533d7bc3345b by Abseil Team <absl-team@google.com>: Changed absl's import of std::string_view to using string_view = std::string_view. This should help tools (e.g. include-what-you-use) discover where absl::string_view is defined. PiperOrigin-RevId: 303169095 GitOrigin-RevId: 2dd5008c7b4176859e320c7c337078adb173b662 Change-Id: I1e18ae08e23686ac963e7ea5e5bd499e18d51048
2020-03-31 21:32:35 +02:00
} else {
AddNode(node);
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
}
}
}
CordRep* ConcatNodes() {
CordRep* sum = nullptr;
for (auto* node : trees_) {
if (node == nullptr) continue;
sum = PrependNode(node, sum);
root_length_ -= node->length;
if (root_length_ == 0) break;
}
ABSL_INTERNAL_CHECK(sum != nullptr, "Failed to locate sum node");
return VerifyTree(sum);
}
private:
CordRep* AppendNode(CordRep* node, CordRep* sum) {
return (sum == nullptr) ? node : MakeConcat(sum, node);
}
CordRep* PrependNode(CordRep* node, CordRep* sum) {
return (sum == nullptr) ? node : MakeConcat(node, sum);
}
void AddNode(CordRep* node) {
CordRep* sum = nullptr;
// Collect together everything with which we will merge with node
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
int i = 0;
for (; node->length > min_length[i + 1]; ++i) {
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
auto& tree_at_i = trees_[i];
if (tree_at_i == nullptr) continue;
sum = PrependNode(tree_at_i, sum);
tree_at_i = nullptr;
}
sum = AppendNode(node, sum);
// Insert sum into appropriate place in the forest
for (; sum->length >= min_length[i]; ++i) {
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
auto& tree_at_i = trees_[i];
if (tree_at_i == nullptr) continue;
sum = MakeConcat(tree_at_i, sum);
tree_at_i = nullptr;
}
// min_length[0] == 1, which means sum->length >= min_length[0]
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
assert(i > 0);
trees_[i - 1] = sum;
}
// Make concat node trying to resue existing CordRepConcat nodes we
// already collected in the concat_freelist_.
CordRep* MakeConcat(CordRep* left, CordRep* right) {
if (concat_freelist_ == nullptr) return RawConcat(left, right);
CordRepConcat* rep = concat_freelist_;
if (concat_freelist_->left == nullptr) {
concat_freelist_ = nullptr;
} else {
concat_freelist_ = concat_freelist_->left->concat();
}
SetConcatChildren(rep, left, right);
return rep;
}
static void CheckNode(CordRep* node) {
ABSL_INTERNAL_CHECK(node->length != 0u, "");
if (node->tag == CONCAT) {
ABSL_INTERNAL_CHECK(node->concat()->left != nullptr, "");
ABSL_INTERNAL_CHECK(node->concat()->right != nullptr, "");
ABSL_INTERNAL_CHECK(node->length == (node->concat()->left->length +
node->concat()->right->length),
"");
}
}
size_t root_length_;
// use an inlined vector instead of a flat array to get bounds checking
absl::InlinedVector<CordRep*, kInlinedVectorSize> trees_;
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
// List of concat nodes we can re-use for Cord balancing.
CordRepConcat* concat_freelist_ = nullptr;
};
static CordRep* Rebalance(CordRep* node) {
VerifyTree(node);
assert(node->tag == CONCAT);
if (node->length == 0) {
return nullptr;
}
CordForest forest(node->length);
forest.Build(node);
return forest.ConcatNodes();
}
// --------------------------------------------------------------------
// Comparators
namespace {
int ClampResult(int memcmp_res) {
return static_cast<int>(memcmp_res > 0) - static_cast<int>(memcmp_res < 0);
}
int CompareChunks(absl::string_view* lhs, absl::string_view* rhs,
size_t* size_to_compare) {
size_t compared_size = std::min(lhs->size(), rhs->size());
assert(*size_to_compare >= compared_size);
*size_to_compare -= compared_size;
int memcmp_res = ::memcmp(lhs->data(), rhs->data(), compared_size);
if (memcmp_res != 0) return memcmp_res;
lhs->remove_prefix(compared_size);
rhs->remove_prefix(compared_size);
return 0;
}
// This overload set computes comparison results from memcmp result. This
// interface is used inside GenericCompare below. Differet implementations
// are specialized for int and bool. For int we clamp result to {-1, 0, 1}
// set. For bool we just interested in "value == 0".
template <typename ResultType>
ResultType ComputeCompareResult(int memcmp_res) {
return ClampResult(memcmp_res);
}
template <>
bool ComputeCompareResult<bool>(int memcmp_res) {
return memcmp_res == 0;
}
} // namespace
// Helper routine. Locates the first flat chunk of the Cord without
// initializing the iterator.
inline absl::string_view Cord::InlineRep::FindFlatStartPiece() const {
size_t n = data_[kMaxInline];
if (n <= kMaxInline) {
return absl::string_view(data_, n);
}
CordRep* node = tree();
if (node->tag >= FLAT) {
return absl::string_view(node->data, node->length);
}
if (node->tag == EXTERNAL) {
return absl::string_view(node->external()->base, node->length);
}
// Walk down the left branches until we hit a non-CONCAT node.
while (node->tag == CONCAT) {
node = node->concat()->left;
}
// Get the child node if we encounter a SUBSTRING.
size_t offset = 0;
size_t length = node->length;
assert(length != 0);
if (node->tag == SUBSTRING) {
offset = node->substring()->start;
node = node->substring()->child;
}
if (node->tag >= FLAT) {
return absl::string_view(node->data + offset, length);
}
assert((node->tag == EXTERNAL) && "Expect FLAT or EXTERNAL node here");
return absl::string_view(node->external()->base + offset, length);
}
inline int Cord::CompareSlowPath(absl::string_view rhs, size_t compared_size,
size_t size_to_compare) const {
auto advance = [](Cord::ChunkIterator* it, absl::string_view* chunk) {
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
if (!chunk->empty()) return true;
++*it;
if (it->bytes_remaining_ == 0) return false;
*chunk = **it;
return true;
};
Cord::ChunkIterator lhs_it = chunk_begin();
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
// compared_size is inside first chunk.
absl::string_view lhs_chunk =
(lhs_it.bytes_remaining_ != 0) ? *lhs_it : absl::string_view();
assert(compared_size <= lhs_chunk.size());
assert(compared_size <= rhs.size());
lhs_chunk.remove_prefix(compared_size);
rhs.remove_prefix(compared_size);
size_to_compare -= compared_size; // skip already compared size.
while (advance(&lhs_it, &lhs_chunk) && !rhs.empty()) {
int comparison_result = CompareChunks(&lhs_chunk, &rhs, &size_to_compare);
if (comparison_result != 0) return comparison_result;
if (size_to_compare == 0) return 0;
}
return static_cast<int>(rhs.empty()) - static_cast<int>(lhs_chunk.empty());
}
inline int Cord::CompareSlowPath(const Cord& rhs, size_t compared_size,
size_t size_to_compare) const {
auto advance = [](Cord::ChunkIterator* it, absl::string_view* chunk) {
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
if (!chunk->empty()) return true;
++*it;
if (it->bytes_remaining_ == 0) return false;
*chunk = **it;
return true;
};
Cord::ChunkIterator lhs_it = chunk_begin();
Cord::ChunkIterator rhs_it = rhs.chunk_begin();
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
// compared_size is inside both first chunks.
absl::string_view lhs_chunk =
(lhs_it.bytes_remaining_ != 0) ? *lhs_it : absl::string_view();
absl::string_view rhs_chunk =
(rhs_it.bytes_remaining_ != 0) ? *rhs_it : absl::string_view();
assert(compared_size <= lhs_chunk.size());
assert(compared_size <= rhs_chunk.size());
lhs_chunk.remove_prefix(compared_size);
rhs_chunk.remove_prefix(compared_size);
size_to_compare -= compared_size; // skip already compared size.
while (advance(&lhs_it, &lhs_chunk) && advance(&rhs_it, &rhs_chunk)) {
int memcmp_res = CompareChunks(&lhs_chunk, &rhs_chunk, &size_to_compare);
if (memcmp_res != 0) return memcmp_res;
if (size_to_compare == 0) return 0;
}
return static_cast<int>(rhs_chunk.empty()) -
static_cast<int>(lhs_chunk.empty());
}
inline absl::string_view Cord::GetFirstChunk(const Cord& c) {
return c.contents_.FindFlatStartPiece();
}
inline absl::string_view Cord::GetFirstChunk(absl::string_view sv) {
return sv;
}
// Compares up to 'size_to_compare' bytes of 'lhs' with 'rhs'. It is assumed
// that 'size_to_compare' is greater that size of smallest of first chunks.
template <typename ResultType, typename RHS>
ResultType GenericCompare(const Cord& lhs, const RHS& rhs,
size_t size_to_compare) {
absl::string_view lhs_chunk = Cord::GetFirstChunk(lhs);
absl::string_view rhs_chunk = Cord::GetFirstChunk(rhs);
size_t compared_size = std::min(lhs_chunk.size(), rhs_chunk.size());
assert(size_to_compare >= compared_size);
int memcmp_res = ::memcmp(lhs_chunk.data(), rhs_chunk.data(), compared_size);
if (compared_size == size_to_compare || memcmp_res != 0) {
return ComputeCompareResult<ResultType>(memcmp_res);
}
return ComputeCompareResult<ResultType>(
lhs.CompareSlowPath(rhs, compared_size, size_to_compare));
}
bool Cord::EqualsImpl(absl::string_view rhs, size_t size_to_compare) const {
return GenericCompare<bool>(*this, rhs, size_to_compare);
}
bool Cord::EqualsImpl(const Cord& rhs, size_t size_to_compare) const {
return GenericCompare<bool>(*this, rhs, size_to_compare);
}
template <typename RHS>
inline int SharedCompareImpl(const Cord& lhs, const RHS& rhs) {
size_t lhs_size = lhs.size();
size_t rhs_size = rhs.size();
if (lhs_size == rhs_size) {
return GenericCompare<int>(lhs, rhs, lhs_size);
}
if (lhs_size < rhs_size) {
auto data_comp_res = GenericCompare<int>(lhs, rhs, lhs_size);
return data_comp_res == 0 ? -1 : data_comp_res;
}
auto data_comp_res = GenericCompare<int>(lhs, rhs, rhs_size);
return data_comp_res == 0 ? +1 : data_comp_res;
}
int Cord::Compare(absl::string_view rhs) const {
return SharedCompareImpl(*this, rhs);
}
int Cord::CompareImpl(const Cord& rhs) const {
return SharedCompareImpl(*this, rhs);
}
bool Cord::EndsWith(absl::string_view rhs) const {
size_t my_size = size();
size_t rhs_size = rhs.size();
if (my_size < rhs_size) return false;
Cord tmp(*this);
tmp.RemovePrefix(my_size - rhs_size);
return tmp.EqualsImpl(rhs, rhs_size);
}
bool Cord::EndsWith(const Cord& rhs) const {
size_t my_size = size();
size_t rhs_size = rhs.size();
if (my_size < rhs_size) return false;
Cord tmp(*this);
tmp.RemovePrefix(my_size - rhs_size);
return tmp.EqualsImpl(rhs, rhs_size);
}
// --------------------------------------------------------------------
// Misc.
Cord::operator std::string() const {
std::string s;
absl::CopyCordToString(*this, &s);
return s;
}
void CopyCordToString(const Cord& src, std::string* dst) {
if (!src.contents_.is_tree()) {
src.contents_.CopyTo(dst);
} else {
absl::strings_internal::STLStringResizeUninitialized(dst, src.size());
src.CopyToArraySlowPath(&(*dst)[0]);
}
}
void Cord::CopyToArraySlowPath(char* dst) const {
assert(contents_.is_tree());
absl::string_view fragment;
if (GetFlatAux(contents_.tree(), &fragment)) {
memcpy(dst, fragment.data(), fragment.size());
return;
}
for (absl::string_view chunk : Chunks()) {
memcpy(dst, chunk.data(), chunk.size());
dst += chunk.size();
}
}
Cord::ChunkIterator& Cord::ChunkIterator::operator++() {
Export of internal Abseil changes -- 2dd5008c7b4176859e320c7c337078adb173b662 by Tom Manshreck <shreck@google.com>: Internal change PiperOrigin-RevId: 304022549 -- 6442abd78697b03cfe698b0d0dac7f1eb4b5cb38 by Andy Getzendanner <durandal@google.com>: Internal change PiperOrigin-RevId: 303890410 -- eb8b37b468b0f23da09d3de714272928ef61f942 by Gennadiy Rozental <rogeeff@google.com>: Roll changes forward with ChunkIterator templatized. This should facilitate usage of "small" chunk iterator for a regular usage and proper "big" iterator internally in Cord implementation. This way Cord users are not exposed to stack size overhead if they have a lot of chunk iterators or recursive implementation which relies on chunk iterators. PiperOrigin-RevId: 303877118 -- 9623c569e7c55b45254e95f2d14c5badf9c901aa by Gennadiy Rozental <rogeeff@google.com>: Switch Flags implementation of fast type id to use absl/base/internal/fast_type_id.h PiperOrigin-RevId: 303861019 -- e2931e8d53c86d0816da6bbc8ba58cf5a3a443bb by Matthew Brown <matthewbr@google.com>: Internal Change PiperOrigin-RevId: 303832407 -- b549ed6e441e920b8ad6f02a80b9fd543820ef86 by Tom Manshreck <shreck@google.com>: Update Cord header file comments to Abseil standards PiperOrigin-RevId: 303823232 -- fc633d4f31a2d058f2b6a7029fc7c9820cd71c92 by Evan Brown <ezb@google.com>: Remove top-level const from K/V in map_slot_type::mutable_value and map_slot_type::key. This allows us to move between `map_slot_type::mutable_value`s internally even when the key_type and/or mapped_type specified by the user are const. PiperOrigin-RevId: 303811694 -- 909b3ce7cb3583ee9c374d36ff5f82bba02a1b64 by Derek Mauro <dmauro@google.com>: Add hardening assertions to the preconditions of absl::Cord PiperOrigin-RevId: 303419537 -- 9d32f79eabd54e6cb17bcc28b53e9bcfeb3cf6f4 by Greg Falcon <gfalcon@google.com>: Don't use MSVC-specific bit manipulations when using Clang on Windows. This fixes a compiler warning. Note that we do not have continuous testing for this configuration; this CL is best-effort support. PiperOrigin-RevId: 303322582 -- f6e0a35a2b9081d2a9eef73789b7bc1b5e46e5ad by Gennadiy Rozental <rogeeff@google.com>: Introduce standlone FastTypeId utility to represent compile time unique type id. PiperOrigin-RevId: 303180545 -- 99120e9fbdb5b2d327139ab8f617533d7bc3345b by Abseil Team <absl-team@google.com>: Changed absl's import of std::string_view to using string_view = std::string_view. This should help tools (e.g. include-what-you-use) discover where absl::string_view is defined. PiperOrigin-RevId: 303169095 GitOrigin-RevId: 2dd5008c7b4176859e320c7c337078adb173b662 Change-Id: I1e18ae08e23686ac963e7ea5e5bd499e18d51048
2020-03-31 21:32:35 +02:00
ABSL_HARDENING_ASSERT(bytes_remaining_ > 0 &&
"Attempted to iterate past `end()`");
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
assert(bytes_remaining_ >= current_chunk_.size());
bytes_remaining_ -= current_chunk_.size();
if (stack_of_right_children_.empty()) {
assert(!current_chunk_.empty()); // Called on invalid iterator.
// We have reached the end of the Cord.
return *this;
}
// Process the next node on the stack.
CordRep* node = stack_of_right_children_.back();
stack_of_right_children_.pop_back();
// Walk down the left branches until we hit a non-CONCAT node. Save the
// right children to the stack for subsequent traversal.
while (node->tag == CONCAT) {
stack_of_right_children_.push_back(node->concat()->right);
node = node->concat()->left;
}
// Get the child node if we encounter a SUBSTRING.
size_t offset = 0;
size_t length = node->length;
if (node->tag == SUBSTRING) {
offset = node->substring()->start;
node = node->substring()->child;
}
assert(node->tag == EXTERNAL || node->tag >= FLAT);
assert(length != 0);
const char* data =
node->tag == EXTERNAL ? node->external()->base : node->data;
current_chunk_ = absl::string_view(data + offset, length);
current_leaf_ = node;
return *this;
}
Cord Cord::ChunkIterator::AdvanceAndReadBytes(size_t n) {
Export of internal Abseil changes -- 2dd5008c7b4176859e320c7c337078adb173b662 by Tom Manshreck <shreck@google.com>: Internal change PiperOrigin-RevId: 304022549 -- 6442abd78697b03cfe698b0d0dac7f1eb4b5cb38 by Andy Getzendanner <durandal@google.com>: Internal change PiperOrigin-RevId: 303890410 -- eb8b37b468b0f23da09d3de714272928ef61f942 by Gennadiy Rozental <rogeeff@google.com>: Roll changes forward with ChunkIterator templatized. This should facilitate usage of "small" chunk iterator for a regular usage and proper "big" iterator internally in Cord implementation. This way Cord users are not exposed to stack size overhead if they have a lot of chunk iterators or recursive implementation which relies on chunk iterators. PiperOrigin-RevId: 303877118 -- 9623c569e7c55b45254e95f2d14c5badf9c901aa by Gennadiy Rozental <rogeeff@google.com>: Switch Flags implementation of fast type id to use absl/base/internal/fast_type_id.h PiperOrigin-RevId: 303861019 -- e2931e8d53c86d0816da6bbc8ba58cf5a3a443bb by Matthew Brown <matthewbr@google.com>: Internal Change PiperOrigin-RevId: 303832407 -- b549ed6e441e920b8ad6f02a80b9fd543820ef86 by Tom Manshreck <shreck@google.com>: Update Cord header file comments to Abseil standards PiperOrigin-RevId: 303823232 -- fc633d4f31a2d058f2b6a7029fc7c9820cd71c92 by Evan Brown <ezb@google.com>: Remove top-level const from K/V in map_slot_type::mutable_value and map_slot_type::key. This allows us to move between `map_slot_type::mutable_value`s internally even when the key_type and/or mapped_type specified by the user are const. PiperOrigin-RevId: 303811694 -- 909b3ce7cb3583ee9c374d36ff5f82bba02a1b64 by Derek Mauro <dmauro@google.com>: Add hardening assertions to the preconditions of absl::Cord PiperOrigin-RevId: 303419537 -- 9d32f79eabd54e6cb17bcc28b53e9bcfeb3cf6f4 by Greg Falcon <gfalcon@google.com>: Don't use MSVC-specific bit manipulations when using Clang on Windows. This fixes a compiler warning. Note that we do not have continuous testing for this configuration; this CL is best-effort support. PiperOrigin-RevId: 303322582 -- f6e0a35a2b9081d2a9eef73789b7bc1b5e46e5ad by Gennadiy Rozental <rogeeff@google.com>: Introduce standlone FastTypeId utility to represent compile time unique type id. PiperOrigin-RevId: 303180545 -- 99120e9fbdb5b2d327139ab8f617533d7bc3345b by Abseil Team <absl-team@google.com>: Changed absl's import of std::string_view to using string_view = std::string_view. This should help tools (e.g. include-what-you-use) discover where absl::string_view is defined. PiperOrigin-RevId: 303169095 GitOrigin-RevId: 2dd5008c7b4176859e320c7c337078adb173b662 Change-Id: I1e18ae08e23686ac963e7ea5e5bd499e18d51048
2020-03-31 21:32:35 +02:00
ABSL_HARDENING_ASSERT(bytes_remaining_ >= n &&
"Attempted to iterate past `end()`");
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
Cord subcord;
if (n <= InlineRep::kMaxInline) {
// Range to read fits in inline data. Flatten it.
char* data = subcord.contents_.set_data(n);
while (n > current_chunk_.size()) {
memcpy(data, current_chunk_.data(), current_chunk_.size());
data += current_chunk_.size();
n -= current_chunk_.size();
++*this;
}
memcpy(data, current_chunk_.data(), n);
if (n < current_chunk_.size()) {
RemoveChunkPrefix(n);
} else if (n > 0) {
++*this;
}
return subcord;
}
if (n < current_chunk_.size()) {
// Range to read is a proper subrange of the current chunk.
assert(current_leaf_ != nullptr);
CordRep* subnode = Ref(current_leaf_);
const char* data =
subnode->tag == EXTERNAL ? subnode->external()->base : subnode->data;
subnode = NewSubstring(subnode, current_chunk_.data() - data, n);
subcord.contents_.set_tree(VerifyTree(subnode));
RemoveChunkPrefix(n);
return subcord;
}
// Range to read begins with a proper subrange of the current chunk.
assert(!current_chunk_.empty());
assert(current_leaf_ != nullptr);
CordRep* subnode = Ref(current_leaf_);
if (current_chunk_.size() < subnode->length) {
const char* data =
subnode->tag == EXTERNAL ? subnode->external()->base : subnode->data;
subnode = NewSubstring(subnode, current_chunk_.data() - data,
current_chunk_.size());
}
n -= current_chunk_.size();
bytes_remaining_ -= current_chunk_.size();
// Process the next node(s) on the stack, reading whole subtrees depending on
// their length and how many bytes we are advancing.
CordRep* node = nullptr;
while (!stack_of_right_children_.empty()) {
node = stack_of_right_children_.back();
stack_of_right_children_.pop_back();
if (node->length > n) break;
// TODO(qrczak): This might unnecessarily recreate existing concat nodes.
// Avoiding that would need pretty complicated logic (instead of
// current_leaf_, keep current_subtree_ which points to the highest node
// such that the current leaf can be found on the path of left children
// starting from current_subtree_; delay creating subnode while node is
// below current_subtree_; find the proper node along the path of left
// children starting from current_subtree_ if this loop exits while staying
// below current_subtree_; etc.; alternatively, push parents instead of
// right children on the stack).
subnode = Concat(subnode, Ref(node));
n -= node->length;
bytes_remaining_ -= node->length;
node = nullptr;
}
if (node == nullptr) {
// We have reached the end of the Cord.
assert(bytes_remaining_ == 0);
subcord.contents_.set_tree(VerifyTree(subnode));
return subcord;
}
// Walk down the appropriate branches until we hit a non-CONCAT node. Save the
// right children to the stack for subsequent traversal.
while (node->tag == CONCAT) {
if (node->concat()->left->length > n) {
// Push right, descend left.
stack_of_right_children_.push_back(node->concat()->right);
node = node->concat()->left;
} else {
// Read left, descend right.
subnode = Concat(subnode, Ref(node->concat()->left));
n -= node->concat()->left->length;
bytes_remaining_ -= node->concat()->left->length;
node = node->concat()->right;
}
}
// Get the child node if we encounter a SUBSTRING.
size_t offset = 0;
size_t length = node->length;
if (node->tag == SUBSTRING) {
offset = node->substring()->start;
node = node->substring()->child;
}
// Range to read ends with a proper (possibly empty) subrange of the current
// chunk.
assert(node->tag == EXTERNAL || node->tag >= FLAT);
assert(length > n);
if (n > 0) subnode = Concat(subnode, NewSubstring(Ref(node), offset, n));
const char* data =
node->tag == EXTERNAL ? node->external()->base : node->data;
current_chunk_ = absl::string_view(data + offset + n, length - n);
current_leaf_ = node;
bytes_remaining_ -= n;
subcord.contents_.set_tree(VerifyTree(subnode));
return subcord;
}
void Cord::ChunkIterator::AdvanceBytesSlowPath(size_t n) {
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
assert(bytes_remaining_ >= n && "Attempted to iterate past `end()`");
assert(n >= current_chunk_.size()); // This should only be called when
// iterating to a new node.
n -= current_chunk_.size();
bytes_remaining_ -= current_chunk_.size();
// Process the next node(s) on the stack, skipping whole subtrees depending on
// their length and how many bytes we are advancing.
CordRep* node = nullptr;
while (!stack_of_right_children_.empty()) {
node = stack_of_right_children_.back();
stack_of_right_children_.pop_back();
if (node->length > n) break;
n -= node->length;
bytes_remaining_ -= node->length;
node = nullptr;
}
if (node == nullptr) {
// We have reached the end of the Cord.
assert(bytes_remaining_ == 0);
return;
}
// Walk down the appropriate branches until we hit a non-CONCAT node. Save the
// right children to the stack for subsequent traversal.
while (node->tag == CONCAT) {
if (node->concat()->left->length > n) {
// Push right, descend left.
stack_of_right_children_.push_back(node->concat()->right);
node = node->concat()->left;
} else {
// Skip left, descend right.
n -= node->concat()->left->length;
bytes_remaining_ -= node->concat()->left->length;
node = node->concat()->right;
}
}
// Get the child node if we encounter a SUBSTRING.
size_t offset = 0;
size_t length = node->length;
if (node->tag == SUBSTRING) {
offset = node->substring()->start;
node = node->substring()->child;
}
assert(node->tag == EXTERNAL || node->tag >= FLAT);
assert(length > n);
const char* data =
node->tag == EXTERNAL ? node->external()->base : node->data;
current_chunk_ = absl::string_view(data + offset + n, length - n);
current_leaf_ = node;
bytes_remaining_ -= n;
}
char Cord::operator[](size_t i) const {
Export of internal Abseil changes -- 2dd5008c7b4176859e320c7c337078adb173b662 by Tom Manshreck <shreck@google.com>: Internal change PiperOrigin-RevId: 304022549 -- 6442abd78697b03cfe698b0d0dac7f1eb4b5cb38 by Andy Getzendanner <durandal@google.com>: Internal change PiperOrigin-RevId: 303890410 -- eb8b37b468b0f23da09d3de714272928ef61f942 by Gennadiy Rozental <rogeeff@google.com>: Roll changes forward with ChunkIterator templatized. This should facilitate usage of "small" chunk iterator for a regular usage and proper "big" iterator internally in Cord implementation. This way Cord users are not exposed to stack size overhead if they have a lot of chunk iterators or recursive implementation which relies on chunk iterators. PiperOrigin-RevId: 303877118 -- 9623c569e7c55b45254e95f2d14c5badf9c901aa by Gennadiy Rozental <rogeeff@google.com>: Switch Flags implementation of fast type id to use absl/base/internal/fast_type_id.h PiperOrigin-RevId: 303861019 -- e2931e8d53c86d0816da6bbc8ba58cf5a3a443bb by Matthew Brown <matthewbr@google.com>: Internal Change PiperOrigin-RevId: 303832407 -- b549ed6e441e920b8ad6f02a80b9fd543820ef86 by Tom Manshreck <shreck@google.com>: Update Cord header file comments to Abseil standards PiperOrigin-RevId: 303823232 -- fc633d4f31a2d058f2b6a7029fc7c9820cd71c92 by Evan Brown <ezb@google.com>: Remove top-level const from K/V in map_slot_type::mutable_value and map_slot_type::key. This allows us to move between `map_slot_type::mutable_value`s internally even when the key_type and/or mapped_type specified by the user are const. PiperOrigin-RevId: 303811694 -- 909b3ce7cb3583ee9c374d36ff5f82bba02a1b64 by Derek Mauro <dmauro@google.com>: Add hardening assertions to the preconditions of absl::Cord PiperOrigin-RevId: 303419537 -- 9d32f79eabd54e6cb17bcc28b53e9bcfeb3cf6f4 by Greg Falcon <gfalcon@google.com>: Don't use MSVC-specific bit manipulations when using Clang on Windows. This fixes a compiler warning. Note that we do not have continuous testing for this configuration; this CL is best-effort support. PiperOrigin-RevId: 303322582 -- f6e0a35a2b9081d2a9eef73789b7bc1b5e46e5ad by Gennadiy Rozental <rogeeff@google.com>: Introduce standlone FastTypeId utility to represent compile time unique type id. PiperOrigin-RevId: 303180545 -- 99120e9fbdb5b2d327139ab8f617533d7bc3345b by Abseil Team <absl-team@google.com>: Changed absl's import of std::string_view to using string_view = std::string_view. This should help tools (e.g. include-what-you-use) discover where absl::string_view is defined. PiperOrigin-RevId: 303169095 GitOrigin-RevId: 2dd5008c7b4176859e320c7c337078adb173b662 Change-Id: I1e18ae08e23686ac963e7ea5e5bd499e18d51048
2020-03-31 21:32:35 +02:00
ABSL_HARDENING_ASSERT(i < size());
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
size_t offset = i;
const CordRep* rep = contents_.tree();
if (rep == nullptr) {
return contents_.data()[i];
}
while (true) {
assert(rep != nullptr);
assert(offset < rep->length);
if (rep->tag >= FLAT) {
// Get the "i"th character directly from the flat array.
return rep->data[offset];
} else if (rep->tag == EXTERNAL) {
// Get the "i"th character from the external array.
return rep->external()->base[offset];
} else if (rep->tag == CONCAT) {
// Recursively branch to the side of the concatenation that the "i"th
// character is on.
size_t left_length = rep->concat()->left->length;
if (offset < left_length) {
rep = rep->concat()->left;
} else {
offset -= left_length;
rep = rep->concat()->right;
}
} else {
// This must be a substring a node, so bypass it to get to the child.
assert(rep->tag == SUBSTRING);
offset += rep->substring()->start;
rep = rep->substring()->child;
}
}
}
absl::string_view Cord::FlattenSlowPath() {
size_t total_size = size();
CordRep* new_rep;
char* new_buffer;
// Try to put the contents into a new flat rep. If they won't fit in the
// biggest possible flat node, use an external rep instead.
if (total_size <= kMaxFlatLength) {
new_rep = NewFlat(total_size);
new_rep->length = total_size;
new_buffer = new_rep->data;
CopyToArraySlowPath(new_buffer);
} else {
new_buffer = std::allocator<char>().allocate(total_size);
CopyToArraySlowPath(new_buffer);
new_rep = absl::cord_internal::NewExternalRep(
absl::string_view(new_buffer, total_size), [](absl::string_view s) {
std::allocator<char>().deallocate(const_cast<char*>(s.data()),
s.size());
});
}
Unref(contents_.tree());
contents_.set_tree(new_rep);
return absl::string_view(new_buffer, total_size);
}
/* static */ bool Cord::GetFlatAux(CordRep* rep, absl::string_view* fragment) {
assert(rep != nullptr);
if (rep->tag >= FLAT) {
*fragment = absl::string_view(rep->data, rep->length);
return true;
} else if (rep->tag == EXTERNAL) {
*fragment = absl::string_view(rep->external()->base, rep->length);
return true;
} else if (rep->tag == SUBSTRING) {
CordRep* child = rep->substring()->child;
if (child->tag >= FLAT) {
*fragment =
absl::string_view(child->data + rep->substring()->start, rep->length);
return true;
} else if (child->tag == EXTERNAL) {
*fragment = absl::string_view(
child->external()->base + rep->substring()->start, rep->length);
return true;
}
}
return false;
}
/* static */ void Cord::ForEachChunkAux(
absl::cord_internal::CordRep* rep,
absl::FunctionRef<void(absl::string_view)> callback) {
assert(rep != nullptr);
int stack_pos = 0;
constexpr int stack_max = 128;
// Stack of right branches for tree traversal
absl::cord_internal::CordRep* stack[stack_max];
absl::cord_internal::CordRep* current_node = rep;
while (true) {
if (current_node->tag == CONCAT) {
if (stack_pos == stack_max) {
// There's no more room on our stack array to add another right branch,
// and the idea is to avoid allocations, so call this function
// recursively to navigate this subtree further. (This is not something
// we expect to happen in practice).
ForEachChunkAux(current_node, callback);
// Pop the next right branch and iterate.
current_node = stack[--stack_pos];
continue;
} else {
// Save the right branch for later traversal and continue down the left
// branch.
stack[stack_pos++] = current_node->concat()->right;
current_node = current_node->concat()->left;
continue;
}
}
// This is a leaf node, so invoke our callback.
absl::string_view chunk;
bool success = GetFlatAux(current_node, &chunk);
assert(success);
if (success) {
callback(chunk);
}
if (stack_pos == 0) {
// end of traversal
return;
}
current_node = stack[--stack_pos];
}
}
static void DumpNode(CordRep* rep, bool include_data, std::ostream* os) {
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
const int kIndentStep = 1;
int indent = 0;
absl::InlinedVector<CordRep*, kInlinedVectorSize> stack;
absl::InlinedVector<int, kInlinedVectorSize> indents;
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
for (;;) {
*os << std::setw(3) << rep->refcount.Get();
*os << " " << std::setw(7) << rep->length;
*os << " [";
if (include_data) *os << static_cast<void*>(rep);
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
*os << "]";
*os << " " << (IsRootBalanced(rep) ? 'b' : 'u');
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
*os << " " << std::setw(indent) << "";
if (rep->tag == CONCAT) {
*os << "CONCAT depth=" << Depth(rep) << "\n";
indent += kIndentStep;
indents.push_back(indent);
stack.push_back(rep->concat()->right);
rep = rep->concat()->left;
} else if (rep->tag == SUBSTRING) {
*os << "SUBSTRING @ " << rep->substring()->start << "\n";
indent += kIndentStep;
rep = rep->substring()->child;
} else { // Leaf
if (rep->tag == EXTERNAL) {
*os << "EXTERNAL [";
if (include_data)
*os << absl::CEscape(std::string(rep->external()->base, rep->length));
*os << "]\n";
} else {
*os << "FLAT cap=" << TagToLength(rep->tag) << " [";
if (include_data)
*os << absl::CEscape(std::string(rep->data, rep->length));
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
*os << "]\n";
}
if (stack.empty()) break;
rep = stack.back();
stack.pop_back();
indent = indents.back();
indents.pop_back();
}
}
ABSL_INTERNAL_CHECK(indents.empty(), "");
}
static std::string ReportError(CordRep* root, CordRep* node) {
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
std::ostringstream buf;
buf << "Error at node " << node << " in:";
DumpNode(root, true, &buf);
return buf.str();
}
static bool VerifyNode(CordRep* root, CordRep* start_node,
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
bool full_validation) {
absl::InlinedVector<CordRep*, 2> worklist;
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
worklist.push_back(start_node);
do {
CordRep* node = worklist.back();
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
worklist.pop_back();
ABSL_INTERNAL_CHECK(node != nullptr, ReportError(root, node));
if (node != root) {
ABSL_INTERNAL_CHECK(node->length != 0, ReportError(root, node));
}
if (node->tag == CONCAT) {
ABSL_INTERNAL_CHECK(node->concat()->left != nullptr,
ReportError(root, node));
ABSL_INTERNAL_CHECK(node->concat()->right != nullptr,
ReportError(root, node));
ABSL_INTERNAL_CHECK((node->length == node->concat()->left->length +
node->concat()->right->length),
ReportError(root, node));
if (full_validation) {
worklist.push_back(node->concat()->right);
worklist.push_back(node->concat()->left);
}
} else if (node->tag >= FLAT) {
ABSL_INTERNAL_CHECK(node->length <= TagToLength(node->tag),
ReportError(root, node));
} else if (node->tag == EXTERNAL) {
ABSL_INTERNAL_CHECK(node->external()->base != nullptr,
ReportError(root, node));
} else if (node->tag == SUBSTRING) {
ABSL_INTERNAL_CHECK(
node->substring()->start < node->substring()->child->length,
ReportError(root, node));
ABSL_INTERNAL_CHECK(node->substring()->start + node->length <=
node->substring()->child->length,
ReportError(root, node));
}
} while (!worklist.empty());
return true;
}
// Traverses the tree and computes the total memory allocated.
/* static */ size_t Cord::MemoryUsageAux(const CordRep* rep) {
size_t total_mem_usage = 0;
// Allow a quick exit for the common case that the root is a leaf.
if (RepMemoryUsageLeaf(rep, &total_mem_usage)) {
return total_mem_usage;
}
// Iterate over the tree. cur_node is never a leaf node and leaf nodes will
// never be appended to tree_stack. This reduces overhead from manipulating
// tree_stack.
absl::InlinedVector<const CordRep*, kInlinedVectorSize> tree_stack;
Export of internal Abseil changes -- 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 by Abseil Team <absl-team@google.com>: Internal changes PiperOrigin-RevId: 295164378 -- 74990f100b3f4172c770ef8c76c05c8e99febdde by Xiaoyi Zhang <zhangxy@google.com>: Release `absl::Cord`. PiperOrigin-RevId: 295161959 -- 6018c57f43c45c31dc1a61c0cd75fa2aa9be8dab by Gennadiy Rozental <rogeeff@google.com>: Introduce independent notion of FlagStaticTypeID. This change separates static flag value type identification from the type specific "vtable" with all the operations specific to value type. This change allows us to do the following: * We can move most of "vtable" implementation from handle header, which will become public soon, into implementation details of Abseil Flag. * We can combine back marshalling ops and general ops into a single vtable routine. They were split previously to facilitate type identification without requiring marshalling routines to be exposed in header. * We do not need to store two vtable pointers. We can now store only one. The static type id can be deduced on request. Overall we are saving 24 bytes per flag according to size_tester run. PiperOrigin-RevId: 295149687 -- 986b78e9ba571aa85154e70bda4580edd45bb7bf by Abseil Team <absl-team@google.com>: Update internal comments. PiperOrigin-RevId: 295030681 -- 825412b29fd6015027bbc3e5f802706eee0d2837 by Matthew Brown <matthewbr@google.com>: Change str_format_internal::ConversionChar to an enum (from a struct-wrapped enum). PiperOrigin-RevId: 294987462 -- f9f88d91809d2cc33fc129df70fa93e7a2c35c69 by Derek Mauro <dmauro@google.com>: Use more precise wording in the question on live-at-head PiperOrigin-RevId: 294957679 GitOrigin-RevId: 97faa5fdfa4cd5d7a74cd9332cddd8a7c1e67b89 Change-Id: I081e70d148ffac7296d65e2a2f775f643eaf70bf
2020-02-14 18:41:25 +01:00
const CordRep* cur_node = rep;
while (true) {
const CordRep* next_node = nullptr;
if (cur_node->tag == CONCAT) {
total_mem_usage += sizeof(CordRepConcat);
const CordRep* left = cur_node->concat()->left;
if (!RepMemoryUsageLeaf(left, &total_mem_usage)) {
next_node = left;
}
const CordRep* right = cur_node->concat()->right;
if (!RepMemoryUsageLeaf(right, &total_mem_usage)) {
if (next_node) {
tree_stack.push_back(next_node);
}
next_node = right;
}
} else {
// Since cur_node is not a leaf or a concat node it must be a substring.
assert(cur_node->tag == SUBSTRING);
total_mem_usage += sizeof(CordRepSubstring);
next_node = cur_node->substring()->child;
if (RepMemoryUsageLeaf(next_node, &total_mem_usage)) {
next_node = nullptr;
}
}
if (!next_node) {
if (tree_stack.empty()) {
return total_mem_usage;
}
next_node = tree_stack.back();
tree_stack.pop_back();
}
cur_node = next_node;
}
}
std::ostream& operator<<(std::ostream& out, const Cord& cord) {
for (absl::string_view chunk : cord.Chunks()) {
out.write(chunk.data(), chunk.size());
}
return out;
}
namespace strings_internal {
size_t CordTestAccess::FlatOverhead() { return kFlatOverhead; }
size_t CordTestAccess::MaxFlatLength() { return kMaxFlatLength; }
size_t CordTestAccess::FlatTagToLength(uint8_t tag) {
return TagToLength(tag);
}
uint8_t CordTestAccess::LengthToTag(size_t s) {
ABSL_INTERNAL_CHECK(s <= kMaxFlatLength, absl::StrCat("Invalid length ", s));
return AllocatedSizeToTag(s + kFlatOverhead);
}
size_t CordTestAccess::SizeofCordRepConcat() { return sizeof(CordRepConcat); }
size_t CordTestAccess::SizeofCordRepExternal() {
return sizeof(CordRepExternal);
}
size_t CordTestAccess::SizeofCordRepSubstring() {
return sizeof(CordRepSubstring);
}
} // namespace strings_internal
ABSL_NAMESPACE_END
} // namespace absl