v8/test/mjsunit/string-external-cached.js
Santiago Aboy Solanes c92572ba2f Revert "[objects] Remove MakeExternal case for uncached internal strings"
This reverts commit 3a6f75ac94.

Reason for revert: performance regressions https://bugs.chromium.org/p/chromium/issues/detail?id=1163063

Original change's description:
> [objects] Remove MakeExternal case for uncached internal strings
>
> Concurrently accessing internal external uncached strings is not
> thread-safe. We are removing a case where we can make such a string
> through MakeExternal.
>
> Bug: v8:7790
> Change-Id: I958062c15cf40ccc330600bb572de98620866e54
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2565511
> Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#71573}

TBR=leszeks@chromium.org,solanes@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: v8:7790
Change-Id: I5dcc734869c3c921eacd89426309141127a85f47
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2633547
Reviewed-by: Santiago Aboy Solanes <solanes@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72123}
2021-01-15 20:57:04 +00:00

122 lines
5.1 KiB
JavaScript

// Copyright 2010 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// Flags: --expose-externalize-string --expose-gc
// Test data pointer caching of external strings.
function test() {
// Test string.charAt.
var charat_str = new Array(5);
charat_str[0] = "0123456789ABCDEF0123456789ABCDEF\
0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF\
0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF\
0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF\
0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF0123456789ABCDEF";
charat_str[1] = "0123456789ABCDEF";
for (var i = 0; i < 6; i++) charat_str[1] += charat_str[1];
try { // String can only be externalized once
externalizeString(charat_str[0], false);
externalizeString(charat_str[1], true);
} catch (ex) { }
charat_str[2] = charat_str[0].slice(0, -1);
charat_str[3] = charat_str[1].slice(0, -1);
charat_str[4] = charat_str[0] + charat_str[0];
for (var i = 0; i < 5; i++) {
assertEquals('B', charat_str[i].charAt(6*16 + 11));
assertEquals('C', charat_str[i].charAt(6*16 + 12));
assertEquals('A', charat_str[i].charAt(3*16 + 10));
assertEquals('B', charat_str[i].charAt(3*16 + 11));
}
charat_short = "01234";
try { // String can only be externalized once
externalizeString(charat_short, true);
} catch (ex) { }
assertEquals("1", charat_short.charAt(1));
// Test regexp and short substring.
var re = /(A|B)/;
var rere = /(T.{1,2}B)/;
var ascii = "ABCDEFGHIJKLMNOPQRST";
var twobyte = "_ABCDEFGHIJKLMNOPQRST";
try {
externalizeString(ascii, false);
externalizeString(twobyte, true);
} catch (ex) { }
assertTrue(isOneByteString(ascii));
assertFalse(isOneByteString(twobyte));
var ascii_slice = ascii.slice(1,-1);
var twobyte_slice = twobyte.slice(2,-1);
var ascii_cons = ascii + ascii;
var twobyte_cons = twobyte + twobyte;
for (var i = 0; i < 2; i++) {
assertEquals(["A", "A"], re.exec(ascii));
assertEquals(["B", "B"], re.exec(ascii_slice));
assertEquals(["TAB", "TAB"], rere.exec(ascii_cons));
assertEquals(["A", "A"], re.exec(twobyte));
assertEquals(["B", "B"], re.exec(twobyte_slice));
assertEquals(["T_AB", "T_AB"], rere.exec(twobyte_cons));
assertEquals("DEFG", ascii_slice.substr(2, 4));
assertEquals("DEFG", twobyte_slice.substr(2, 4));
assertEquals("DEFG", ascii_cons.substr(3, 4));
assertEquals("DEFG", twobyte_cons.substr(4, 4));
}
// Test adding external strings
var short_ascii = "E=";
var long_ascii = "MCsquared";
var short_twobyte = "E\u1234";
var long_twobyte = "MCsquare\u1234";
try { // String can only be externalized once
externalizeString(short_ascii, false);
externalizeString(long_ascii, false);
externalizeString(short_twobyte, true);
externalizeString(long_twobyte, true);
assertTrue(isOneByteString(short_asii) && isOneByteString(long_ascii));
assertFalse(isOneByteString(short_twobyte) || isOneByteString(long_twobyte));
} catch (ex) { }
assertEquals("E=MCsquared", short_ascii + long_ascii);
assertTrue(isOneByteString(short_ascii + long_ascii));
assertEquals("MCsquaredE=", long_ascii + short_ascii);
assertEquals("E\u1234MCsquare\u1234", short_twobyte + long_twobyte);
assertFalse(isOneByteString(short_twobyte + long_twobyte));
assertEquals("E=MCsquared", "E=" + long_ascii);
assertEquals("E\u1234MCsquared", short_twobyte + "MCsquared");
assertEquals("E\u1234MCsquared", short_twobyte + long_ascii);
assertFalse(isOneByteString(short_twobyte + long_ascii));
}
// Run the test many times to ensure IC-s don't break things.
for (var i = 0; i < 10; i++) {
test();
}
// Clean up string to make Valgrind happy.
gc();
gc();