tree c5c05a9093337278c98dc0468277e2e85793b9e3
parent ebf63094c2dc4284ceb90347a1963c20e6190c27
author SingleAccretion <62474226+SingleAccretion@users.noreply.github.com> 1702664198 +0300
committer Copybara-Service <copybara-worker@google.com> 1702664283 -0800

[lld][WebAssembly] Add an `--initial-heap` option (#75594)

It is beneficial to preallocate a certain number of pages in the linear
memory (i. e. use the "minimum" field of WASM memories) so that fewer
"memory.grow"s are needed at startup.

So far, the way to do that has been to pass the "--initial-memory"
option to the linker. It works, but has the very significant downside of
requiring the user to know the size of static data beforehand, as it
must not exceed the number of bytes passed-in as "--initial-memory".

The new "--initial-heap" option avoids this downside by simply appending
the specified number of pages to static data (and stack), regardless of
how large they already are.

Ref: https://github.com/emscripten-core/emscripten/issues/20888.
GitOrigin-RevId: b2cdf3cc4c08729d0ff582d55e40793a20bbcdcc