Граф коммитов

50 Коммитов

Автор SHA1 Сообщение Дата
Stephan T. Lavavej 9a9820df1a
Toolset update: VS 2022 17.0 Preview 2 (#2064) 2021-07-19 17:53:06 -07:00
Michael Schellenberger Costa 96f4b66105
Fix missing `_CONSTEXPR20_CONTAINER` on `_Alloc_temporary` (#1962) 2021-06-11 20:18:56 -07:00
Adam Bucior e326ec1dd9
Optimizations for unreachable sentinels (#1810)
Co-authored-by: Casey Carter <cartec69@gmail.com>
Co-authored-by: Stephan T. Lavavej <stl@nuwen.net>
2021-06-11 19:35:51 -07:00
Charlie Barto c12089e489
P0645R10 <format> Text Formatting (#1821)
Co-authored-by: Casey Carter <cacarter@microsoft.com>
Co-authored-by: Charles Barto <barto.charlie@gmail.com>
Co-authored-by: Elnar Dakeshov <55715127+eldakesh-ms@users.noreply.github.com>
Co-authored-by: MattStephanson <68978048+MattStephanson@users.noreply.github.com>
Co-authored-by: Michael Schellenberger Costa <mschellenbergercosta@googlemail.com>
Co-authored-by: mnatsuhara <46756417+mnatsuhara@users.noreply.github.com>
Co-authored-by: S. B. Tam <cpplearner@outlook.com>
Co-authored-by: statementreply <statementreply@gmail.com>
Co-authored-by: Stephan T. Lavavej <stl@microsoft.com>
2021-04-15 00:30:44 -07:00
Adam Bucior cf15e49e0e
More optimizations for contiguous iterators (#1772) 2021-04-05 16:41:00 -07:00
Adam Bucior dcba13b91e
Optimizations for contiguous iterators (#1433)
Co-authored-by: Stephan T. Lavavej <stl@nuwen.net>
Co-authored-by: Casey Carter <cacarter@microsoft.com>
2021-03-22 21:03:26 -07:00
S. B. Tam 8e428c87f0
_Uglify some non-reserved names (#1743) 2021-03-22 17:47:13 -07:00
Casey Carter 038e07bf3f
Implement ranges::split_view (#1731) 2021-03-18 13:25:34 -07:00
Michael Schellenberger Costa 194efde4bd
Fix ranges::uninitialized_copy/uninitialized_move for trivial types (#1713) 2021-03-04 14:44:44 -08:00
Michael Schellenberger Costa 52b7b3205f
P0980R1 constexpr std::string (#1502)
Co-authored-by: Miya Natsuhara <minatsuh@microsoft.com>
Co-authored-by: Stephan T. Lavavej <stl@microsoft.com>
2021-02-26 21:38:32 -08:00
Adam Bucior 66ca0f30e8
Uses-Allocator and Guaranteed Copy Elision For Piecewise Construction (#1668)
Co-authored-by: ArtemSarmini <16746066+ArtemSarmini@users.noreply.github.com>
Co-authored-by: Michael Schellenberger Costa <mschellenbergercosta@gmail.com>
Co-authored-by: Stephan T. Lavavej <stl@nuwen.net>
2021-02-25 18:26:14 -08:00
Stephan T. Lavavej b52c3797e2
P1614R2 Adding Spaceship <=> To The Library (#1678)
Co-authored-by: Ahana Mukhopadhyay <t-ahmukh@microsoft.com>
Co-authored-by: Anju Del Moral Gonzalez <judelmor@microsoft.com>
Co-authored-by: Casey Carter <cacarter@microsoft.com>
Co-authored-by: Charlie Barto <chbarto@microsoft.com>
Co-authored-by: Curtis Bezault <cubezaul@microsoft.com>
Co-authored-by: d-winsor <danwin@microsoft.com>
Co-authored-by: Michael Schellenberger Costa <mschellenbergercosta@googlemail.com>
Co-authored-by: statementreply <statementreply@gmail.com>
Co-authored-by: Stephan T. Lavavej <stl@microsoft.com>
2021-02-24 16:19:31 -08:00
Michael Schellenberger Costa 28678411ce
Fix uninitialized_meow memcpy optimization (#1548)
Co-authored-by: Stephan T. Lavavej <stl@nuwen.net>
2021-02-17 22:21:05 -08:00
Michael Schellenberger Costa a31bd6ed6b
P1004R2 constexpr std::vector (#1407)
Co-authored-by: Miya Natsuhara <minatsuh@microsoft.com>
Co-authored-by: Stephan T. Lavavej <stl@microsoft.com>
2021-02-16 23:54:27 -08:00
Michael Schellenberger Costa 47cd70315d
Prepare the constexpr machinery needed for string and vector (#1546)
Co-authored-by: Miya Natsuhara <minatsuh@microsoft.com>
Co-authored-by: Stephan T. Lavavej <stl@microsoft.com>
2021-02-03 13:54:37 -08:00
Casey Carter 355f8f560e
Update LLVM submodule reference (#1594)
Co-authored-by: Stephan T. Lavavej <stl@microsoft.com>
2021-02-01 19:43:49 -08:00
Michael S. Rizkalla d1f6fe969f
<xmemory>: remove deprecated std::allocator members in C++20 (#1585) 2021-02-01 19:35:06 -08:00
Michael Schellenberger Costa a5b13ff8fb
Implement allocating algorithms for ranges (#1383)
Co-authored-by: Casey Carter <cacarter@microsoft.com>
Co-authored-by: Stephan T. Lavavej <stl@nuwen.net>
2021-01-27 02:02:49 -08:00
Michael S. Rizkalla 256197425b
P0784R7 Library Support For More constexpr Containers (#1369)
Co-authored-by: Adam Bucior <35536269+AdamBucior@users.noreply.github.com>
Co-authored-by: Curtis Jacques Bezault <curtbezault@gmail.com>
Co-authored-by: Michael Schellenberger Costa <mschellenbergercosta@gmail.com>
Co-authored-by: mnatsuhara <46756417+mnatsuhara@users.noreply.github.com>
Co-authored-by: Stephan T. Lavavej <stl@microsoft.com>
2021-01-07 19:01:52 -08:00
Stephan T. Lavavej 2ce62b5848
Always use `if constexpr`, require CUDA 10.1 Update 2 (#1544) 2021-01-05 17:19:12 -08:00
Stephan T. Lavavej 68b344c9dc Run clang-format 11; no manual changes. 2020-12-10 09:27:45 -08:00
Adam Bucior 9bb2a983df
P1771R1 [[nodiscard]] For Constructors (#1495)
Co-authored-by: Stephan T. Lavavej <stl@microsoft.com>
2020-12-02 15:10:23 -08:00
futuarmo 6fe20e62a2
LWG-3170 deprecated std::allocator<T>::is_always_equal (#1501)
Co-authored-by: Stephan T. Lavavej <stl@microsoft.com>
2020-12-01 15:39:26 -08:00
Stephan T. Lavavej 7e07ed8188
Improve type traits usage (#1413) 2020-11-06 16:31:40 -08:00
Adam Bucior a27d894d63
Use memset in even more cases (#1273)
Co-authored-by: Casey Carter <cartec69@gmail.com>
Co-authored-by: Stephan T. Lavavej <stl@microsoft.com>
2020-10-29 00:12:36 -07:00
Casey Carter 09459e77d7
No, unique address! (#1363)
MSVC is finally getting around to implementing `[[no_unique_address]]`, which will result in class layout differing with Clang. Let's comment out the uses that are not yet so commented until we reach compiler parity.
2020-10-23 16:48:24 -07:00
Casey Carter 3d88a64538
Minimal changes to support constexpr allocation in MSVC (#1313)
* Minimal changes to support constexpr allocation in MSVC

* Define `_CONSTEXPR20_DYNALLOC` macro to `constexpr` when the compiler defines `__cpp_constexpr_dynamic_alloc` and `inline` otherwise.
* Implement and test `ranges::construct_at` and `ranges::destroy_at`, mark them (and `std` flavors) `_CONSTEXPR20_DYNALLOC`.
* Implement `ranges::destroy` and `ranges::destroy_n` which share machinery with `ranges::destroy_at` with minimal test coverage. (More to follow.)

[This is a dual of internal MSVC-PR-275909.]
2020-09-22 15:02:43 -07:00
Casey Carter 0e4f6b5df4
Revert "Revert "Implement common_iterator (#1092)" (#1265)" (#1268)
This reverts commit 6156ec32d5.
2020-09-15 20:57:30 -07:00
Casey Carter 6156ec32d5
Revert "Implement common_iterator (#1092)" (#1265)
This reverts commit 30e7a1bab3.
2020-09-04 15:58:20 -07:00
Adam Bucior d6f32c889d
Use memset and memcmp in a bit more cases (#1160)
Fixes #1183.

Co-authored-by: Alex Guteniev <gutenev@gmail.com>
Co-authored-by: Stephan T. Lavavej <stl@microsoft.com>
2020-09-04 11:21:21 -07:00
Michael Schellenberger Costa 30e7a1bab3
Implement common_iterator (#1092)
Co-authored-by: Casey Carter <cacarter@microsoft.com>
2020-09-04 11:12:50 -07:00
Casey Carter 7f29487be5
Implement ranges::uninitialized_move (#1137) 2020-08-12 12:47:52 -07:00
Stephan T. Lavavej 40c3f1fe9a
Code cleanup: avoid macro-like identifiers, remove double newlines (#865) 2020-05-29 17:51:28 -07:00
Stephan T. Lavavej e4bc00e70c
Remove and update compiler bug workarounds (#742) 2020-04-30 02:23:37 -07:00
Michael Schellenberger Costa ca032aebb0
Remove _ITERATOR_DEBUG_ARRAY_OVERLOADS (#735)
Fixes #660.

Also move `_Array_(const_)?iterator` from `<xutility>` to `<array>`, since it's no longer needed by the IDAO.
2020-04-24 18:44:01 -07:00
Casey Carter ae34ee631f
Require MSVC 19.26 and Clang 10 in the STL (#708)
* `<yvals_core.h>` changes:
  * Clang 10 `_HAS_CONDITIONAL_EXPLICIT` in C++14 mode (Only CUDA now requires the `_HAS_CONDITIONAL_EXPLICIT == 0` code paths)
  * reject Clang < 10
  * reject MSVC < 1926

* Unskip libc++ tests that need Concepts and/or `<=>`

* `std/tests/P0595R2_is_constant_evaluated`: We no longer need  suppress the warning Clang 9 emits when it sees the suppression for the warning Clang 10 emits in this test ;)

* `std/tests/VSO_0157762_feature_test_macros`: Remove Clang 9 support

* `std/tests/concepts_matrix.lst`: This is now simply a copy of `usual_latest_matrix.lst` with the `/BE` lines (EDG configs) commented out. (i.e., we now run the Concepts tests with Clang as well as MSVC.)

* Remove workarounds for LLVM-38491 "clang-cl should accept __declspec(allocator)": Replace uses of `_DECLSPEC_ALLOCATOR` with `__declspec(allocator)`, and suppress Clang's warning when the return type isn't a pointer or reference.

* Remove workarounds for LLVM-43531 "clang-format damages 'alternative representations' for operators": Re-enable clang-format in the test which triggered the bug.

* Remove workarounds for LLVM-38478 "clang -fno-ms-compatibility rejects Windows.h": Add -fno-ms-compatibility to the XXX_winsdk_XXX.lst files. (Yes, we still need these because the Windows SDK breaks `/Za`.)

* Drive-by: unskip libc++ new.version now that we implement destroying delete
2020-04-13 13:09:34 -07:00
Billy O'Neal ff83542af4
Update to Clang 10 and Visual Studio 2019 version 16.6p2 (#645)
* Update to Clang 10 and Visual Studio 2019 version 16.6p2

* re-clang-formats the tree to comply with new clang 10 clang-format
* updates our agents to F series VMs which are faster and cheaper for our build workloads
* defaults scale set to 0 VMs and lets the Azure Pipelines service control all resizing
* fix tests to pass with the new compilers

Co-authored by Casey Carter and Curtis Bezault
2020-03-28 18:53:15 -07:00
Daniel Marshall 627eced6ec
P1115R3 erase()/erase_if() Return size_type (#566)
Fixes #555.
2020-02-29 14:35:24 -08:00
Jean Philippe 577827a79a
Consistently use empty braces to construct tags (#497)
Fixes #468.
2020-02-29 14:21:41 -08:00
Billy O'Neal 482f1d8088
Reduce the amount of content included by <array> (#482)
* Reduce the amount of content included by <array>.

Resolves GH-462.

* Demote `back_inserter` and `iterator` to `<iterator>`.
* Demote `_Yarn` to `<xlocinfo>`.
* Demote `_Tidy_guard`, `_Tidy_deallocate_guard`, and `_Nothrow_compare` to `<xmemory>`.
* Promote `_Swap_ranges_unchecked` to `<xutility>`.
* Change `<array>` to include only `<xutility>`.

* Un-demote iterator.

* Workaround many RWC projects that expected std::min and std::max to come from <array>.

* Remove the `_STL_ASSERT` from `std::min` and `std::max`. We normally guard every `op<` with debug checks, but in this case we aren't using it to enforce something like a container invariant; the number of bad op<s we catch with it are likely microscopic.
* Delete `_Min_value` and `_Max_value` from `<utility>`.
* Move `min` and `max` to `<utility>` (in the exact position as the old `_Min_value` and `_Max_value`)
* Change all existing callers of `_Min_value` and `_Max_value` to call `(_STD min)` and `(_STD max)`, respectively.

* Homogenize vector algorithm guards.
2020-02-21 05:55:22 -08:00
Michael Schellenberger Costa b3504262fe
P0619R4 Removing C++17-Deprecated Features (#380)
Fixes #28 and fixes #478.
2020-02-03 02:55:53 -08:00
Billy O'Neal 94d39ed515
Avoid double strlen for string operator+ and implement P1165R1 (#467)
Resolves GH-53.
Resolves GH-456.

Co-authored by: @barcharcraz
Co-authored by: @ArtemSarmini 

This change adds a bespoke constructor to `basic_string` to handle string concat use cases, removing any EH states we previously emitted in our operator+s, avoiding double strlen in our operator+s,

The EH states problem comes from our old pattern:

```
S operator+(a, b) {
    S result;
    result.reserve(a.size() +b.size()); // throws
    result += a; // throws
    result += b; // throws
    return result;
}
```

Here, the compiler does not know that the append operation can't throw, because it doesn't understand `basic_string` and doesn't know the `reserve` has made that always safe. As a result, the compiler emitted EH handing code to call `result`'s destructor after each of the reserve and `operator+=` calls.

Using a bespoke concatenating constructor avoids these problems because there is only one throwing operation (in IDL0 mode). As expected, this results in a small performance win in all concats due to avoiding needing to set up EH stuff, and a large performance win for the `const char*` concats due to the avoided second `strlen`:

Performance:

```
#include <benchmark/benchmark.h>
#include <stdint.h>
#include <string>

constexpr size_t big = 2 << 12;
constexpr size_t multiplier = 64;

static void string_concat_string(benchmark::State &state) {
    std::string x(static_cast<size_t>(state.range(0)), 'a');
    std::string y(static_cast<size_t>(state.range(1)), 'b');
    for (auto _ : state) {
        (void)_;
        benchmark::DoNotOptimize(x + y);
    }
}

BENCHMARK(string_concat_string)->RangeMultiplier(multiplier)->Ranges({{2, big}, {2, big}});

static void string_concat_ntbs(benchmark::State &state) {
    std::string x(static_cast<size_t>(state.range(0)), 'a');
    std::string yBuf(static_cast<size_t>(state.range(1)), 'b');
    const char *const y = yBuf.c_str();
    for (auto _ : state) {
        (void)_;
        benchmark::DoNotOptimize(x + y);
    }
}

BENCHMARK(string_concat_ntbs)->RangeMultiplier(multiplier)->Ranges({{2, big}, {2, big}});

static void string_concat_char(benchmark::State &state) {
    std::string x(static_cast<size_t>(state.range(0)), 'a');
    for (auto _ : state) {
        (void)_;
        benchmark::DoNotOptimize(x + 'b');
    }
}

BENCHMARK(string_concat_char)->Range(2, big);

static void ntbs_concat_string(benchmark::State &state) {
    std::string xBuf(static_cast<size_t>(state.range(0)), 'a');
    const char *const x = xBuf.c_str();
    std::string y(static_cast<size_t>(state.range(1)), 'b');
    for (auto _ : state) {
        (void)_;
        benchmark::DoNotOptimize(x + y);
    }
}

BENCHMARK(ntbs_concat_string)->RangeMultiplier(multiplier)->Ranges({{2, big}, {2, big}});

static void char_concat_string(benchmark::State &state) {
    std::string x(static_cast<size_t>(state.range(0)), 'a');
    for (auto _ : state) {
        (void)_;
        benchmark::DoNotOptimize('b' + x);
    }
}

BENCHMARK(char_concat_string)->Range(2, big);

BENCHMARK_MAIN();

```

Times are in NS on a Ryzen Threadripper 3970X, improvements are `((Old/New)-1)*100`

|                                 | old x64 | new x64 | improvement | old x86 | new x86 | improvement |
| ------------------------------- | ------- | ------- | ----------- | ------- |-------- | ----------- |
| string_concat_string/2/2        | 12.8697 | 5.78125 |     122.61% | 13.9029 | 11.0696 |      25.60% |
| string_concat_string/64/2       |  62.779 | 61.3839 |       2.27% | 66.4394 | 61.6296 |       7.80% |
| string_concat_string/4096/2     | 125.558 | 124.512 |       0.84% | 124.477 | 117.606 |       5.84% |
| string_concat_string/8192/2     | 188.337 | 184.152 |       2.27% | 189.982 | 185.598 |       2.36% |
| string_concat_string/2/64       | 64.5229 | 64.1741 |       0.54% | 67.1338 | 61.4962 |       9.17% |
| string_concat_string/64/64      | 65.5692 | 59.9888 |       9.30% | 66.7742 | 60.4781 |      10.41% |
| string_concat_string/4096/64    | 122.768 | 122.768 |       0.00% | 126.774 | 116.327 |       8.98% |
| string_concat_string/8192/64    |  190.43 | 181.362 |       5.00% | 188.516 | 186.234 |       1.23% |
| string_concat_string/2/4096     | 125.558 | 119.978 |       4.65% | 120.444 | 111.524 |       8.00% |
| string_concat_string/64/4096    | 125.558 | 119.978 |       4.65% | 122.911 | 117.136 |       4.93% |
| string_concat_string/4096/4096  | 188.337 | 184.152 |       2.27% | 193.337 | 182.357 |       6.02% |
| string_concat_string/8192/4096  | 273.438 | 266.811 |       2.48% | 267.656 | 255.508 |       4.75% |
| string_concat_string/2/8192     | 205.078 | 194.964 |       5.19% | 175.025 | 170.181 |       2.85% |
| string_concat_string/64/8192    | 205.078 | 188.337 |       8.89% | 191.676 |  183.06 |       4.71% |
| string_concat_string/4096/8192  | 266.811 | 256.696 |       3.94% | 267.455 | 255.221 |       4.79% |
| string_concat_string/8192/8192  |  414.69 | 435.965 |      -4.88% | 412.784 |  403.01 |       2.43% |
| string_concat_ntbs/2/2          | 12.8348 |  5.9375 |     116.17% |   14.74 |  11.132 |      32.41% |
| string_concat_ntbs/64/2         | 71.1496 |  59.375 |      19.83% | 70.6934 | 60.9371 |      16.01% |
| string_concat_ntbs/4096/2       | 128.697 | 114.397 |      12.50% | 126.626 | 121.887 |       3.89% |
| string_concat_ntbs/8192/2       | 194.964 | 176.479 |      10.47% | 196.641 |  186.88 |       5.22% |
| string_concat_ntbs/2/64         | 100.446 |  74.986 |      33.95% | 109.082 | 83.3939 |      30.80% |
| string_concat_ntbs/64/64        | 106.027 | 78.4738 |      35.11% | 109.589 | 84.3635 |      29.90% |
| string_concat_ntbs/4096/64      | 164.969 | 138.114 |      19.44% | 165.417 | 142.116 |      16.40% |
| string_concat_ntbs/8192/64      | 224.958 | 200.195 |      12.37% | 228.769 | 200.347 |      14.19% |
| string_concat_ntbs/2/4096       | 2040.32 | 1074.22 |      89.94% | 2877.33 | 1362.74 |     111.14% |
| string_concat_ntbs/64/4096      | 1994.98 | 1074.22 |      85.71% | 2841.93 | 1481.62 |      91.81% |
| string_concat_ntbs/4096/4096    | 2050.78 | 1147.46 |      78.72% | 2907.78 | 1550.82 |      87.50% |
| string_concat_ntbs/8192/4096    | 2148.44 | 1227.68 |      75.00% | 2966.92 | 1583.78 |      87.33% |
| string_concat_ntbs/2/8192       | 3934.14 | 2099.61 |      87.37% | 5563.32 | 2736.56 |     103.30% |
| string_concat_ntbs/64/8192      | 3989.95 | 1994.98 |     100.00% | 5456.84 | 2823.53 |      93.26% |
| string_concat_ntbs/4096/8192    | 4049.24 | 2197.27 |      84.29% | 5674.02 | 2957.04 |      91.88% |
| string_concat_ntbs/8192/8192    | 4237.58 | 2249.58 |      88.37% | 5755.07 | 3095.65 |      85.91% |
| string_concat_char/2            | 12.8348 | 3.44936 |     272.09% | 11.1104 | 10.6976 |       3.86% |
| string_concat_char/8            | 8.99833 | 3.45285 |     160.61% | 11.1964 | 10.6928 |       4.71% |
| string_concat_char/64           | 65.5692 | 60.9375 |       7.60% | 65.7585 | 60.0182 |       9.56% |
| string_concat_char/512          | 72.5446 | 69.7545 |       4.00% |  83.952 | 79.5254 |       5.57% |
| string_concat_char/4096         | 125.558 | 119.978 |       4.65% | 123.475 | 117.103 |       5.44% |
| string_concat_char/8192         |  190.43 | 187.988 |       1.30% | 189.181 | 185.174 |       2.16% |
| ntbs_concat_string/2/2          | 13.4975 | 6.13839 |     119.89% | 14.8623 |   11.09 |      34.02% |
| ntbs_concat_string/64/2         |  104.98 | 79.5201 |      32.02% | 112.207 | 83.7111 |      34.04% |
| ntbs_concat_string/4096/2       | 2085.66 | 1098.63 |      89.84% | 2815.19 | 1456.08 |      93.34% |
| ntbs_concat_string/8192/2       | 3899.27 | 2099.61 |      85.71% | 5544.52 | 2765.16 |     100.51% |
| ntbs_concat_string/2/64         | 71.4983 |  62.779 |      13.89% | 72.6602 | 63.1953 |      14.98% |
| ntbs_concat_string/64/64        |  104.98 | 80.2176 |      30.87% | 111.073 | 81.8413 |      35.72% |
| ntbs_concat_string/4096/64      | 2085.66 | 1074.22 |      94.16% | 2789.73 |  1318.7 |     111.55% |
| ntbs_concat_string/8192/64      | 3989.95 | 2085.66 |      91.30% | 5486.85 | 2693.83 |     103.68% |
| ntbs_concat_string/2/4096       | 136.719 | 128.348 |       6.52% | 122.605 |  114.44 |       7.13% |
| ntbs_concat_string/64/4096      | 167.411 | 142.997 |      17.07% | 168.572 | 138.566 |      21.65% |
| ntbs_concat_string/4096/40      | 2099.61 | 1171.88 |      79.17% | 2923.85 | 1539.02 |      89.98% |
| ntbs_concat_string/8192/40      | 4098.07 | 2246.09 |      82.45% | 5669.34 | 3005.25 |      88.65% |
| ntbs_concat_string/2/8192       |   213.1 | 199.498 |       6.82% | 178.197 | 168.532 |       5.73% |
| ntbs_concat_string/64/8192      | 223.214 | 214.844 |       3.90% | 232.263 | 203.722 |      14.01% |
| ntbs_concat_string/4096/81      | 2148.44 | 1255.58 |      71.11% | 2980.78 | 1612.97 |      84.80% |
| ntbs_concat_string/8192/81      | 4237.58 | 2406.53 |      76.09% | 5775.55 | 3067.94 |      88.25% |
| char_concat_string/2            | 11.1607 | 3.60631 |     209.48% | 11.2101 | 10.7192 |       4.58% |
| char_concat_string/8            | 11.4746 | 3.52958 |     225.10% | 11.4595 |  10.709 |       7.01% |
| char_concat_string/64           | 65.5692 | 66.9643 |      -2.08% | 66.6272 | 60.8601 |       9.48% |
| char_concat_string/512          | 68.0106 | 73.2422 |      -7.14% | 91.1946 | 83.0791 |       9.77% |
| char_concat_string/4096         | 125.558 | 122.768 |       2.27% | 119.432 | 110.031 |       8.54% |
| char_concat_string/8192         | 199.498 | 199.498 |       0.00% | 171.895 | 169.173 |       1.61% |


Code size:
```
#include <string>

std::string strings(const std::string& a, const std::string& b) {
    return a + b;
}
std::string string_ntbs(const std::string& a, const char * b) {
    return a + b;
}
std::string string_char(const std::string& a, char b) {
    return a + b;
}
std::string ntbs_string(const char * a, const std::string& b) {
    return a + b;
}
std::string char_string(char a, const std::string& b) {
    return a + b;
}
```

Sizes are in bytes for the `.obj`, "Times Original" is New/Old, `cl /EHsc /W4 /WX /c /O2 .\code_size.cpp`:

| Bytes | Before | After  | Times Original |
| ----- | ------ | ------ | -------------- |
| x64   | 70,290 | 34,192 |          0.486 |
| x86   | 47,152 | 28,792 |          0.611 |
2020-01-31 16:45:39 -08:00
Billy O'Neal 3447e56030 Implement constexpr algorithms. (#425)
* Implement constexpr algorithms.

Resolves GH-6 ( P0202R3 ), resolves GH-38 ( P0879R0 ), and drive-by fixes GH-414.

Everywhere: Add constexpr, _CONSTEXPR20, and _CONSTEXPR20_ICE to things.

skipped_tests.txt: Turn on all tests previously blocked by missing constexpr algorithms (and exchange and swap). Mark those algorithms that cannot be turned on that we have outstanding PRs for with their associated PRs.
yvals_core.h: Turn on feature test macros.
xutility:
* Move the _Ptr_cat family down to copy, and fix associated SHOUTY comments to indicate that this is really an implementation detail of copy, not something the rest of the standard library intends to use directly. Removed and clarified some of the comments as requested by Casey Carter.
* Extract _Copy_n_core which implements copy_n using only the core language (rather than memcpy-as-an-intrinsic). Note that we cannot use __builtin_memcpy or similar to avoid the is_constant_evaluated check here; builtin_memcpy only works in constexpr contexts when the inputs are of type char.
numeric: Refactor as suggested by GH-414.

* Attempt alternate fix of GH-414 suggested by Stephan.

* Stephan product code PR comments:

* _Swap_ranges_unchecked => _CONSTEXPR20
* _Idl_dist_add => _NODISCARD (and remove comments)
* is_permutation => _NODISCARD
* Add yvals_core.h comments.

* Delete unused _Copy_n_core and TRANSITION, DevCom-889321 comment.

* Put the comments in the right place and remove phantom braces.
2020-01-22 17:57:27 -08:00
Daniel Marshall 48c7f31413 <utility> Deprecate std::rel_ops & resolve #403 (#402)
Co-authored-by: Casey Carter <cartec69@gmail.com>
Co-authored-by: Billy O'Neal <billy.oneal@gmail.com>
2020-01-08 19:16:40 -08:00
Casey Carter 1e8b8d4eef
[range.iter.ops], default_sentinel, and unreachable_sentinel (#329)
Implements iterator primitive operations `std::ranges::advance`, `std::ranges::next`, `std::ranges::prev`, and `std::ranges::distance`; as well as `std::default_sentinel` and `std::unreachable_sentinel`.

This change reworks the STL's iterator unwrapping machinery to enable unwrapping of C++20 move-only single-pass iterators (and `if constepxr`s all the things). Consequently, `_Iter_ref_t`, `_Iter_value_t`, and `_Iter_diff_t` resolve to `iter_reference_t`, `iter_value_t`, and `iter_difference_t` (respectively) in `__cpp_lib_concepts` (soon to be C++20) mode. This change necessitates some fixes to `unique_copy` and `_Fill_memset_is_safe` which both assume that `_Iter_value_t<T>` is well-formed for any iterator `T`. (`iter_value_t<T>` does not have that property: it is only well-formed when `readable<T>`.)

I notably haven't unified `default_sentinel_t` with `_Default_sentinel` out of an abundance of paranoia. Our `move_iterator` is comparable with `_Default_sentinel`, which is not the case for `std::default_sentinel`.

Drive-by:
* This change `if constexpr`-izes `unique_copy`.
2019-12-02 15:32:14 -08:00
Daniel Marshall 28ec9a3295 P1209R0 erase_if(), erase() (#236)
Resolves #55.

* Deprecate experimental::erase

* Implement P1209R0

* Update yvals_core.h

* Update deprecations and remove <experimental/xutility>

* move and reorder erase/erase_if

* moved _Erase and remove and friends to <xmemory>

* Consistently place erase_if() definitions.
2019-11-01 14:32:39 -07:00
Nathan Ward 379e61781a P0356R5 bind_front() (#158)
Resolves #13.
2019-10-22 17:15:35 -07:00
Stephan T. Lavavej 712b7971bd
Update comments to follow custom autolink syntax (#168)
* Use custom autolinks.

* Also update .clang-format.

* Use ArchivedOS.
2019-10-11 13:43:06 -07:00
Casey Carter c5e2e3f799 Ranges <range> machinery
* Implements a selection of support machinery in `std::ranges` and adds the `<ranges>` header. Primarily consists of the range access customization point objects:
  * `ranges::begin`
  * `ranges::end`
  * `ranges::cbegin`
  * `ranges::cend`
  * `ranges::rbegin`
  * `ranges::rend`
  * `ranges::crbegin`
  * `ranges::crend`
  * `ranges::size`
  * `ranges::empty`
  * `ranges::data`
  * `ranges::cdata`

  and range concepts:

  * `ranges::range`
  * `ranges::output_range`
  * `ranges::input_range`
  * `ranges::forward_range`
  * `ranges::bidirectional_range`
  * `ranges::random_access_range`
  * `ranges::contiguous_range`
  * `ranges::sized_range`
  * `ranges::view`
  * `ranges::common_range`

  and the associated type aliases:

  * `ranges::iterator_t`
  * `ranges::sentinel_t`
  * `ranges::range_value_t`
  * `ranges::range_reference_t`
  * `ranges::range_difference_t`
  * `ranges::range_rvalue_reference_t`

* Adds `<ranges>` - which is mostly empty since the support machinery is defined in `<xutility>` so as to be visible to `<algorithm>`

* Annotates [P0896R4](https://wg21.link/p0896r4) as partially implemented in the "`_HAS_CXX20` directly controls" section of `<yvals_core.h>`.

* Touches `<regex>`, `<set>`, and `<unordered_set>` to add partial specializations of `ranges::enable_view` for `match_results` and `(unordered_)?multi?set` as mandated by the WD to override the heuristic.

* Partially implements [P1474R1 "Helpful pointers for `ContiguousIterator`"](https://wg21.link/p1474r1):
  * Push `pointer_traits` from `<xmemory>` and `to_address` from `<memory>` up into `<xutility>`
  * Add `to_address` expression requirement to `contiguous_iterator` concept, and update `P0896R4_ranges_iterator_machinery` appropriately
  * Implement the changes to `ranges::data` (but not `view_interface` since it isn't yet implemented)

* Drive-by:
  * Simplify the definition of `pointer_traits::_Reftype` by eschewing `add_lvalue_reference_t`.
  * Strengthen `reverse_iterator`'s constructors and `make_reverse_iterator` so `ranges::rbegin` and `ranges::rend` can be `noexcept` in more cases
  * Since we're using `_Rng` as the template parameter name for models of `std::ranges::range`, rename a local variable `_Rng` to `_Generator` in `<random>`
2019-09-09 15:31:26 -07:00
Stephan T. Lavavej 219514876e Initial commit. 2019-09-04 15:57:56 -07:00