Revert product changes for find_end vectorization

[StephanTLavavej]

After we merged #4943 (find_end vectorization), @CaseyCarter noticed that the STL-ASan-CI began failing with container-overflow errors.

This reverts the product code changes from #4943 but allows its benchmark and test changes to stand. It also keeps a control flow refactoring of __std_search_impl in stl/src/vector_algorithms.cpp, as I'm convinced it's a lossless transformation.

🙀 Test Failure Log

This can be found by downloading a test failure log as an XML artifact, then running my tools\scripts\print_failures.py to decode it. (Thanks again @CaseyCarter for noticing that the artifact captured the log, which was too big for the usual Azure Pipelines UI to display.)

Click to expand test failure log:

name: std.tests/VSO_0000000_vector_algorithms
output: Build setup steps:
Build steps:
Command: "C:\Program Files\Microsoft Visual Studio\2022\Preview\VC\Tools\MSVC\14.42.34430\bin\HostX64\x64\cl.EXE" "D:\a\_work\1\s\tests\std\tests\VSO_0000000_vector_algorithms\test.cpp" "-ID:\build\out\inc" "-ID:\a\_work\1\s\llvm-project\libcxx\test\support" "-ID:\a\_work\1\s\tests\std\include" "/nologo" "/Od" "/W4" "/w14061" "/w14242" "/w14265" "/w14582" "/w14583" "/w14587" "/w14588" "/w14749" "/w14841" "/w14842" "/w15038" "/w15214" "/w15215" "/w15216" "/w15217" "/w15262" "/sdl" "/WX" "/D_ENABLE_STL_INTERNAL_CHECK" "/bigobj" "/FIforce_include.hpp" "/w14365" "/w14668" "/w15267" "/D_ENFORCE_FACET_SPECIALIZATIONS=1" "/D_STL_CALL_ABORT_INSTEAD_OF_INVALID_PARAMETER" "/EHsc" "/MD" "/std:c++14" "/w14640" "/Zc:threadSafeInit-" "-fsanitize=address" "/Zi" "-FeD:\build\tests\std\tests\VSO_0000000_vector_algorithms\Output\02\VSO_0000000_vector_algorithms.exe" "-link" "-LIBPATH:D:\build\out\lib\amd64" "-LIBPATH:C:\Program Files\Microsoft Visual Studio\2022\Preview\VC\Tools\MSVC\14.42.34430\lib\x64" "/MANIFEST:EMBED" "/debug"
Exit Code: 0 (0x0)
Standard Output:
--
test.cpp
--

Intellisense response file steps:
Test setup steps:
Test steps:
Test step failed unexpectedly.
Command: "D:\build\tests\std\tests\VSO_0000000_vector_algorithms\Output\02\VSO_0000000_vector_algorithms.exe"
Exit Code: 1 (0x1)
Standard Output:
--
This is a randomized test.
DO NOT IGNORE/RERUN ANY FAILURES.
You must report them to the STL maintainers.

Seed vector: 2011068952,1800349505,1657366820,3107043617,1651127980,3260046398,15400191,1873058321,3237234911,3826518008,2914576800,3023067651,2863793863,3176310933,1035976458,1584814113,3645761852,2603711012,398302033,3220332235,3479953918,1627247034,2495544484,3808007759,2668160509,3030858208,1991303010,2331134663,3195459495,1052571626,2267005773,470620865,2856996601,4164755686,3078164348,3648764572,2646527408,3337787984,116391692,2229707523,2856658210,1931813679,292282476,2109247529,3829417261,2935829019,2982250063,622420786,4264727969,4058172462,4079835062,321192426,297423852,4245592591,1875091205,1857304947,1613956918,831694263,968329006,1169475324,1916357803,2982738080,2406543901,3139968786,202519371,246873437,1200258812,1707766541,857178778,3913697687,1530322986,1908672360,835051880,534500434,2428664387,3411225464,123034167,2559113815,3342239464,19158409,4147883316,1433634373,768858233,2449113694,325546895,2700415623,3938328643,3073210044,2285681681,903015171,2179344742,736290914,2905129771,2131266680,2575814788,4136725403,1417281482,3100175328,408599776,3509282416,3758827912,962080411,970932244,3088371761,3925131815,3492369811,758944521,2184515348,2655835272,2861927756,2813182753,509451779,3735905578,2364982079,402539953,1105920053,263634128,875795601,1429437621,1869601088,4142129620,1986893578,2116566250,2950645724,3190596778,1414589206,2642106073,532599899,1799822179,3668986244,3233127745,2791600445,2901570897,458602993,1854330026,424986833,111687351,1606274551,758460865,134981425,1188604210,3549331806,3282138848,773561944,1361887694,22402482,4114180469,464729789,3312719481,1504787436,3872857272,4191435540,1467497249,1319472103,3405620429,2259291454,120503514,2130234242,1863918787,368730050,3525779885,448738331,804249522,2913226562,2325961125,1827461579,1382068634,2912280469,1472785127,822245788,397465641,3233808011,1008885528,1013257583,1938623677,4046731228,516932277,880706749,1298926651,172472773,2462792547,1316302827,800137223,3427808702,950219626,1949787057,1786531086,4265085186,1071593515,1169558681,2852875651,2370238476,769898125,4066886242,2653211205,1428998300,1618935610,114687281,728862980,256932986,1348132859,1551744971,55423173,3562735612,4001567145,2237794644,3244335815,3902729622,1695462421,3742641501,2732329923,1087272810,1957614825,2566432756,4032405094,983038140,3912717552,2456021457,1696554340,3090374432,3736030988,2347373906,640059456,3860235184,742790861,4067577861,3602023206,1297314135,1416388059,1519067742,756191024,2385381113,748996437,1265098562,3569805643,2514002747,276138074,4094160565,3330487062,758482058,3593784580,1812809580,766921760,3381065353,740117692,1950419051,4010365163,3756530706,8765525,1613542144,2851910570,2449425820,1609964223,3573884803,1280740777,16387889,3666837180,361397975,3006417432,2554573412,3185378302,1238586497,3879295604,4084880397,2703845395,571910872,466229177,848239127,929961539,846127199,1890172138,2792640325,1358476327,2782571701,3026179870,807806587,3728639638,814364754,1380231081,1906622436,2108285195,1463027426,396226289,4080045934,491189244,527127807,3150184362,1019696525,2618985245,4009715955,985590636,1320516031,551558302,1779073836,2940974049,4175735776,828939631,2557145166,691689456,3148180338,544628276,282271145,414941916,4121253749,2536515091,1459981188,828724823,1191095279,2749771357,3369369760,1270935465,1820451023,3511452484,121616160,1606010456,3726136436,139266204,27082308,3863850034,2472964748,3522249275,3487409475,127501491,848269134,3553350081,1286525666,1281783698,1382666568,3893982171,2008905543,2648155505,2889575531,814423046,2165914790,108705247,184272403,3646804496,634981345,1882357081,3676732359,214693199,306588649,260299410,4232974665,1899148162,208127625,1904379070,3584762883,3716800050,65955686,43590010,4129309316,4124814887,1286267047,1827185369,2465767878,3643904392,2149954499,295431555,259439948,4046757173,2271350434,916327116,905287810,499631451,4236789356,2954710849,4085008392,2747657282,1275866175,3108735711,1206061667,198133870,927530334,3966029148,2653378031,72299589,3912197471,2102990358,2764342096,3229134931,3156320293,1341610995,3192927223,2337105174,2110060083,1489144010,459911385,550490213,692457889,2624799649,11334890,2406353028,1915807794,605618613,513705456,3864380873,4199956147,2218965101,469655204,864958714,3806644643,834077491,1742017098,2801253004,3860780662,687406354,344065831,2754819679,3174813101,656105269,3968154028,288933350,533773015,2425276143,436291995,3965676620,3312810081,2261859312,2503949923,1605787302,4233843984,1472384500,1473765606,1614887789,2861684869,56448885,1323164365,3764144926,3017510408,2884833810,3861436053,2308726463,500953552,69562809,2415295656,918099702,809684240,1263182173,113151192,906990781,1363217266,3470428302,2533453819,2612193736,3516742804,3710800193,1390981148,3680577752,2772525961,365907877,4249820706,411846345,3397228791,1645638854,884959290,3961736111,3041490195,3734608541,1475309574,36023412,3746665600,1490872667,2131541876,18941448,3640559111,1006035896,941539141,1920429648,687252276,1185217618,3469886766,2570745178,3081518363,1490826935,2617926642,2869511626,2073322834,2808967644,4079209883,2343264819,845969595,4044988658,3454771801,780180754,4263566314,926085622,713064173,3430671900,1778663272,3438181157,412982688,2193876743,1146348340,3222478913,2287237156,1119453240,1734767354,1504208915,3382158195,3421396733,1416047329,733965968,566182400,1222722879,1325861379,1230646915,1518020050,2083111034,1717616525,426871704,3335070254,1420497405,1291879419,4206696464,2465491358,3649624428,3280323781,184482236,4073079772,3807972274,1943983621,93486245,351632978,2161829867,4244967171,4009511684,163510711,206317229,3757585980,3017339704,740813614,3938928483,1141410889,3908464433,3703919474,3784465891,1432087571,1757544277,2904516984,929626878,1759094921,442618468,1470189625,4217400554,1945688789,471523255,3709742932,3677057809,2844062185,2710486911,3218476143,944822773,3584262299,325772606,129803551,1991650842,2369193260,2968008293,50135414,721455388,2191756448,2582620022,2413974665,1302297283,3688522746,4056322878,1669505827,1897232925,3976725825,165337602,4221524198,2316631291,3588144051,1389323383,1747379036,876044655,1031700110,337344199,4273931236,3107679220,4033981379,4271298648,2578611637,498398443,2572783817,172908045,641766931,502499022,2109447611,14925703,970442322,985368944,3224023473,1216830302,12038398,2425830969,376680416,3244397628,1304822910,1060196594,643517479,61412589,2091368317,3456531160,2363326553,1621816927,3356831066,1944015571,3744267984,215429163,4273416040,2414487240,2196848132,3568580393,180029871,3913888601,3697765551,1855512809,3160380217,2928789472,2667895349,3891968106,1038151028,
--
Standard Error:
--
=================================================================
==11852==ERROR: AddressSanitizer: container-overflow on address 0x12c416ba0f52 at pc 0x7ff71f1748fb bp 0x00d79f2fd340 sp 0x00d79f2fd348
READ of size 16 at 0x12c416ba0f52 thread T0
    #0 0x7ff71f1748fa in ``anonymous namespace'::__std_find_end_impl<`anonymous namespace'::_Find_traits_1,unsigned char>'::`33'::<lambda_3>::operator() D:\a\_work\1\s\stl\src\vector_algorithms.cpp:3788
    #1 0x7ff71f14ef9e in `anonymous namespace'::__std_find_end_impl<`anonymous namespace'::_Find_traits_1,unsigned char> D:\a\_work\1\s\stl\src\vector_algorithms.cpp:3819
    #2 0x7ff71f17b698 in __std_find_end_1 D:\a\_work\1\s\stl\src\vector_algorithms.cpp:3999
    #3 0x7ff71e9fca30 in std::_Find_end_vectorized<char const, char const>(char const *const, char const *const, char const *const, unsigned __int64) D:\build\out\inc\algorithm:202
    #4 0x7ff71ea94cd2 in std::find_end<class std::_Vector_const_iterator<class std::_Vector_val<struct std::_Simple_types<char>>>, class std::_Vector_const_iterator<class std::_Vector_val<struct std::_Simple_types<char>>>, struct std::equal_to<void>>(class std::_Vector_const_iterator<class std::_Vector_val<struct std::_Simple_types<char>>>, class std::_Vector_const_iterator<class std::_Vector_val<struct std::_Simple_types<char>>>, class std::_Vector_const_iterator<class std::_Vector_val<struct std::_Simple_types<char>>>, class std::_Vector_const_iterator<class std::_Vector_val<struct std::_Simple_types<char>>>, struct std::equal_to<void>) D:\build\out\inc\algorithm:3220
    #5 0x7ff71ea9483d in std::find_end<class std::_Vector_const_iterator<class std::_Vector_val<struct std::_Simple_types<char>>>, class std::_Vector_const_iterator<class std::_Vector_val<struct std::_Simple_types<char>>>>(class std::_Vector_const_iterator<class std::_Vector_val<struct std::_Simple_types<char>>>, class std::_Vector_const_iterator<class std::_Vector_val<struct std::_Simple_types<char>>>, class std::_Vector_const_iterator<class std::_Vector_val<struct std::_Simple_types<char>>>, class std::_Vector_const_iterator<class std::_Vector_val<struct std::_Simple_types<char>>>) D:\build\out\inc\algorithm:3307
    #6 0x7ff71f05bfef in test_case_search<char>(class std::vector<char, class std::allocator<char>> const &, class std::vector<char, class std::allocator<char>> const &) D:\a\_work\1\s\tests\std\tests\VSO_0000000_vector_algorithms\test.cpp:328
    #7 0x7ff71f0994a6 in test_search<char>(class std::mersenne_twister_engine<unsigned __int64, 64, 312, 156, 31, -5403634167711393303, 29, 6148914691236517205, 17, 8202884508482404352, 37, -2270628950310912, 43, 6364136223846793005> &) D:\a\_work\1\s\tests\std\tests\VSO_0000000_vector_algorithms\test.cpp:372
    #8 0x7ff71e9b1995 in test_vector_algorithms(class std::mersenne_twister_engine<unsigned __int64, 64, 312, 156, 31, -5403634167711393303, 29, 6148914691236517205, 17, 8202884508482404352, 37, -2270628950310912, 43, 6364136223846793005> &) D:\a\_work\1\s\tests\std\tests\VSO_0000000_vector_algorithms\test.cpp:955
    #9 0x7ff71e9b5b67 in <lambda_24b1af959ca32f2eb49b34af9c40a73a>::operator() D:\a\_work\1\s\tests\std\tests\VSO_0000000_vector_algorithms\test.cpp:1368
    #10 0x7ff71eae0dfb in run_randomized_tests_with_different_isa_levels<<lambda_24b1af959ca32f2eb49b34af9c40a73a> > D:\a\_work\1\s\tests\std\include\test_vector_algorithms_support.hpp:55
    #11 0x7ff71e9b5aee in main D:\a\_work\1\s\tests\std\tests\VSO_0000000_vector_algorithms\test.cpp:1367
    #12 0x7ff71f17fb1b in invoke_main D:\a\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:78
    #13 0x7ff71f17fb1b in __scrt_common_main_seh D:\a\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288
    #14 0x7ffb0cd64caf  (C:\Windows\System32\KERNEL32.DLL+0x180014caf)
    #15 0x7ffb0da5ecda  (C:\Windows\SYSTEM32\ntdll.dll+0x18007ecda)

0x12c416ba0f52 is located 18 bytes inside of 200-byte region [0x12c416ba0f40,0x12c416ba1008)
allocated by thread T0 here:
    #0 0x7ff71f17ece5 in operator new(unsigned __int64) D:\a\_work\1\s\src\vctools\asan\llvm\compiler-rt\lib\asan\asan_win_new_scalar_thunk.cpp:40
    #1 0x7ff71f0f2de2 in std::_Default_allocate_traits::_Allocate(unsigned __int64) D:\build\out\inc\xmemory:136
    #2 0x7ff71e9c4075 in std::_Allocate<16, struct std::_Default_allocate_traits>(unsigned __int64) D:\build\out\inc\xmemory:256
    #3 0x7ff71f11fadf in std::allocator<char>::allocate(unsigned __int64) D:\build\out\inc\xmemory:986
    #4 0x7ff71e9c4176 in std::_Allocate_at_least_helper<class std::allocator<char>>(class std::allocator<char> &, unsigned __int64 &) D:\build\out\inc\xmemory:2221
    #5 0x7ff71ea0ef22 in std::vector<char, class std::allocator<char>>::_Reallocate<0>(unsigned __int64 &) D:\build\out\inc\vector:1636
    #6 0x7ff71f134824 in std::vector<char, class std::allocator<char>>::reserve(unsigned __int64) D:\build\out\inc\vector:1713
    #7 0x7ff71f099366 in test_search<char>(class std::mersenne_twister_engine<unsigned __int64, 64, 312, 156, 31, -5403634167711393303, 29, 6148914691236517205, 17, 8202884508482404352, 37, -2270628950310912, 43, 6364136223846793005> &) D:\a\_work\1\s\tests\std\tests\VSO_0000000_vector_algorithms\test.cpp:362
    #8 0x7ff71e9b1995 in test_vector_algorithms(class std::mersenne_twister_engine<unsigned __int64, 64, 312, 156, 31, -5403634167711393303, 29, 6148914691236517205, 17, 8202884508482404352, 37, -2270628950310912, 43, 6364136223846793005> &) D:\a\_work\1\s\tests\std\tests\VSO_0000000_vector_algorithms\test.cpp:955
    #9 0x7ff71e9b5b67 in <lambda_24b1af959ca32f2eb49b34af9c40a73a>::operator() D:\a\_work\1\s\tests\std\tests\VSO_0000000_vector_algorithms\test.cpp:1368
    #10 0x7ff71eae0dfb in run_randomized_tests_with_different_isa_levels<<lambda_24b1af959ca32f2eb49b34af9c40a73a> > D:\a\_work\1\s\tests\std\include\test_vector_algorithms_support.hpp:55
    #11 0x7ff71e9b5aee in main D:\a\_work\1\s\tests\std\tests\VSO_0000000_vector_algorithms\test.cpp:1367
    #12 0x7ff71f17fb1b in invoke_main D:\a\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:78
    #13 0x7ff71f17fb1b in __scrt_common_main_seh D:\a\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288
    #14 0x7ffb0cd64caf  (C:\Windows\System32\KERNEL32.DLL+0x180014caf)
    #15 0x7ffb0da5ecda  (C:\Windows\SYSTEM32\ntdll.dll+0x18007ecda)

HINT: if you don't care about these errors you may set ASAN_OPTIONS=detect_container_overflow=0.
If you suspect a false positive see also: https://github.com/google/sanitizers/wiki/AddressSanitizerContainerOverflow.
SUMMARY: AddressSanitizer: container-overflow D:\a\_work\1\s\stl\src\vector_algorithms.cpp:3788 in ``anonymous namespace'::__std_find_end_impl<`anonymous namespace'::_Find_traits_1,unsigned char>'::`33'::<lambda_3>::operator()
Shadow bytes around the buggy address:
  0x12c416ba0c80: fa fa fa fa fa fa fa fa fd fd fd fd fd fd fd fd
  0x12c416ba0d00: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x12c416ba0d80: fd fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x12c416ba0e00: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x12c416ba0e80: fd fd fd fd fd fd fd fd fd fa fa fa fa fa fa fa
=>0x12c416ba0f00: fa fa fa fa fa fa fa fa 00 00[07]fc fc fc fc fc
  0x12c416ba0f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
  0x12c416ba1000: fc fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x12c416ba1080: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x12c416ba1100: fd fd fd fd fd fd fd fd fd fa fa fa fa fa fa fa
  0x12c416ba1180: fa fa fa fa fa fa fa fa fd fd fd fd fd fd fd fd
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==11852==ABORTING
--

✅ ASan Validation Incantations

Here's how to build the STL with ASan enabled (-DSTL_ASAN_BUILD=ON), then run the test with ASan enabled (-Dtags=ASAN):

title x64
"C:\Program Files\Microsoft Visual Studio\2022\Preview\VC\Auxiliary\Build\vcvarsall.bat" x64
set STL=D:\GitHub\STL
pushd %STL%
git clean -x -d -f
cmake --preset x64 -DSTL_ASAN_BUILD=ON && cmake --build --preset x64

pushd out\x64
python tests\utils\stl-lit\stl-lit.py -o testing_x64.log -Dtags=ASAN --order=random %STL%\tests\std\tests\VSO_0000000_vector_algorithms