Automatically applying components based on crash stacktrace and information from OWNERS files.

If this is incorrect, please apply the Test-Predator-Wrong-Components label.

Automatically assigning owner based on suspected regression changelist https://chromium.googlesource.com/v8/v8/+/bf1e47e6ff10734045b2d6a501da49d20980f742 ([ptr-compr] Switch Smis to 31-bit on 64-bit platforms.).

If this is incorrect, please let us know why and apply the Test-Predator-Wrong-CLs label. If you aren't the correct owner for this issue, please unassign yourself as soon as possible so it can be re-triaged.

This test creates a BigInt whose string representation is longer than the max string length when Smis are 31-bits. So 
Object::ToString() throws and this assertion fails: https://cs.chromium.org/chromium/src/v8/src/objects.cc?q=file:objects.cc&sq=package:chromium&g=0&l=368

Reproduces on 32-bit architectures.

ClusterFuzz has detected this issue as fixed in range 55332:55333.

Detailed report: https://clusterfuzz.com/testcase?key=5711829255585792

Fuzzer: mbarbella_js_mutation
Job Type: linux_msan_d8
Platform Id: linux

Crash Type: Ill
Crash Address: 0x562371d8b4f3
Crash State:
  v8::internal::Object::NoSideEffectsToString
  v8::internal::ErrorUtils::MakeGenericError
  v8::internal::Factory::NewError
  
Sanitizer: memory (MSAN)

Regressed: https://clusterfuzz.com/revisions?job=linux_msan_d8&range=55268:55269
Fixed: https://clusterfuzz.com/revisions?job=linux_msan_d8&range=55332:55333

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=5711829255585792

See https://github.com/google/clusterfuzz-tools for more information.

If you suspect that the result above is incorrect, try re-doing that job on the test case report page.

ClusterFuzz testcase 5711829255585792 is verified as fixed, so closing issue as verified.

If this is incorrect, please add ClusterFuzz-Wrong label and re-open the issue.

31-bit smis were reverted and CF is happy now but the Object::NoSideEffectsToString() issue is still there.

The following revision refers to this bug:
  https://chromium.googlesource.com/v8/v8.git/+/9d493179d85b2030185b8987a9fef1adeef148c2

commit 9d493179d85b2030185b8987a9fef1adeef148c2
Author: Jakob Kummerow <jkummerow@chromium.org>
Date: Wed Aug 29 13:45:28 2018

[bigint] Fix NoSideEffectsToString for 32-bit platforms

On 32-bit platforms, String::kMaxLength is such that not all BigInts
can be converted to Strings. NoSideEffectsToString, however, used to
assume that this conversion always succeeds. This patch adds a check
for the failure case, and returns "<a very large BigInt>" instead of
crashing.
This change is practically unobservable, because actually formatting
such a huge BigInt to String would take "forever", which is also why
there is no regression test.

Bug:  chromium:876628 
Change-Id: I1eacdc1cce753ac5d9ca66e61e479043ab576e07
Reviewed-on: https://chromium-review.googlesource.com/1194004
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55491}
[modify] https://crrev.com/9d493179d85b2030185b8987a9fef1adeef148c2/src/objects.cc
[modify] https://crrev.com/9d493179d85b2030185b8987a9fef1adeef148c2/src/objects/bigint.cc
[modify] https://crrev.com/9d493179d85b2030185b8987a9fef1adeef148c2/src/objects/bigint.h