Commit Graph

2 Commits

Author SHA1 Message Date
Georg Neis
68099bffac [turbofan] Fix bug in Typer::TypeInductionVariablePhi, again
Regrettably the previous fix was flawed because a zero increment can
change the type of the induction variable.

Bug: chromium:1051017
Change-Id: I2d7aeffb2065e739445118a2d0c5f7732eecdcbb
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2064222
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66345}
2020-02-19 16:40:45 +00:00
Georg Neis
a2e971c56d [turbofan] Fix bug in Typer::TypeInductionVariablePhi
The fix in b8b6075021 was insufficient.

The bug is that induction variable typing does not take into account
that the value can become NaN through addition or subtraction of
Infinities. The previous fix incorrectly assumed that this can only
happen when the initial value of the loop variable is an Infinity.

Bug: chromium:1051017
Change-Id: I8c9ffb2925288b80c00e18e7bc22a556bf540733
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2051957
Commit-Queue: Georg Neis <neis@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66258}
2020-02-13 13:29:25 +00:00