For people working on Rust code, compiling in debug mode (Cargo's "dev"
profile) is convenient: debug assertions are turned on, optimization is
turned off, and parallel compilation inside of rustc itself can be
used. These things make the build faster and the debugging experience
more pleasant.
To obtain that currently, one needs to --enable-debug at the Gecko
toplevel, which turns on debug assertions for the entire browser, which
makes things run unreasonably slowly. So it would be desirable to be
able to turn *off* debug mode for the entirety of the browser, but turn
on debug mode for the Rust code only.
Hence this added switch, --enable-rust-debug, which does what it
suggests and defaults to the value of --enable-debug. For our own
sanity and because we judge it a non-existent use case, we do not
support --enable-debug --disable-rust-debug.
This is the same optimization made for ThreadSafeAutoRefCnt in bug
1277709. However, nsStringBuffer uses a 32-bit reference count all the
time, so it can't easily use ThreadSafeAutoRefCnt.
MozReview-Commit-ID: LpB3xaYbaEE
This patch adds a series of fallible methods for the rust ns[C]String
bindings, as well as the `set_length` method, which is the same as the
`SetLength` method in C++. `set_length` is marked as unsafe.
The decision was made to make the fallible methods seperate from the
infallible methods, and to use seperate Rust->C++ bindings for each of
them, rather than only binding the fallible bindings, and unwrapping
them in rust-land. This is to try to match the C++ API as closely as
possible, and to ensure that the behavior matches.
MozReview-Commit-ID: FkSomkFUFGD
The patch changes all uses of SizeOfIncludingThisMustBeUnshared() to
SizeOfIncludingThisIfUnshared(). This incurs the (tiny) cost of an unnecessary
IsReadonly() check for guaranteed-unshared strings, but avoids the possible
assertion failures that would occur when MustBeUnshared() was used incorrectly
on shared strings, which is an easy mistake to make.
ReplaceSubstring() is an O(n*m) algorithm (n being the length of the
string and m being the number of occurrences of aTarget) because we have
to move the remainder of the string, search it again and potentially
memmove most of it again as we find more matches. This patch rewrites
that function to make it O(n+m).
Note that we currently don't build TestStrings.cpp, so the test case in
this patch is not run automatically, but the test case has been verified
to pass separately by moving the test function into Gecko and calling it
during startup and stepping through it in the debugger.
ReplaceSubstring() is an O(n*m) algorithm (n being the length of the
string and m being the number of occurrences of aTarget) because we have
to move the remainder of the string, search it again and potentially
memmove most of it again as we find more matches. This patch rewrites
that function to make it O(n+m).
Note that we currently don't build TestStrings.cpp, so the test case in
this patch is not run automatically, but the test case has been verified
to pass separately by moving the test function into Gecko and calling it
during startup and stepping through it in the debugger.
ReplaceSubstring() is an O(n*m) algorithm (n being the length of the
string and m being the number of occurrences of aTarget) because we have
to move the remainder of the string, search it again and potentially
memmove most of it again as we find more matches. This patch rewrites
that function to make it O(n+m).
Note that we currently don't build TestStrings.cpp, so the test case in
this patch is not run automatically, but the test case has been verified
to pass separately by moving the test function into Gecko and calling it
during startup and stepping through it in the debugger.
