tree 71fafbf15e4270f53a88d8156398f2432ccdb1f8
parent 932ed79a53d4fec0fe65a673144bababd454da0d
author Tom Sepez <tsepez@chromium.org> 1638923537 +0000
committer Pdfium LUCI CQ <pdfium-scoped@luci-project-accounts.iam.gserviceaccount.com> 1638923537 +0000

Avoid N^2 copies in CXFA_FMDotAccessorExpression::ToJavaScript().

The local tempExp1 will be repeatedly copied into its caller's
tempExp1 getting larger each time as the recursion unwinds. The
cost now is we may have to generate a string twice, but we do
so into a single buffer.

The referenced bug seems recurse until we hit the 5000 frame
limit in the depth manager.

We'll probably need a follow-up bug to look at the other temporaries.

Bug: chromium:1274018
Change-Id: Ieafcc1e3e1aab412cbcb447f5bcb87d43ab364a2
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/87732
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>