commit a64a5d112e2b46526d5e9d6300fdeb3e4c004c0e
author Kostya Kortchinsky <kostyak@google.com> Thu Jun 03 12:11:05 2021 -0700
committer Copybara-Service <copybara-worker@google.com> Wed Jun 16 18:24:36 2021 -0700
tree cda727c5a4a1fb1025eb7be6234540b408e30dbc
parent 53e41cd19bcd4e98dcd544603087625a34ac8d13

[scudo] Rework Vector/String

Some platforms (eg: Trusty) are extremelly memory constrained, which
doesn't necessarily work well with some of Scudo's current assumptions.

`Vector` by default (and as such `String` and `ScopedString`) maps a
page, which is a bit of a waste. This CL changes `Vector` to use a
buffer local to the class first, then potentially map more memory if
needed (`ScopedString` currently are all stack based so it would be
stack data). We also want to allow a platform to prevent any dynamic
resizing, so I added a `CanGrow` templated parameter that for now is
always `true` but would be set to `false` on Trusty.

Differential Revision: https://reviews.llvm.org/D103641

GitOrigin-RevId: 868317b3fd765830c07ecf16cbfcf6c7708adc3c