https://bugs.swift.org/browse/SR-6926
This happens when the Parser re-lexing comment tokens that sets
ArtificialEOF at the end of comment range.
It used to cause an assertion failure:
(!value || Kind == tok::identifier) && "only identifiers can be escaped identifiers"
For example: @$S1m3fooyyF
It's needed to change the mangling prefix to $S.
The parser change only affects SIL (and not swift).
I didn't add test case because it will be fully tested when changing the mangling prefix.
* Re-apply "libSyntax: Ensure round-trip printing when we build syntax tree from parser incrementally. (#12709)"
* Re-apply "libSyntax: Root parsing context should hold a reference to the current token in the parser, NFC."
* Re-apply "libSyntax: avoid copying token text when lexing token syntax nodes, NFC. (#12723)"
* Actually fix the container-overflow issue.
This is likely the root cause for memory surge when we always turn on
syntax token lexing. Since the underlying buffer outlives the syntax
tree, it's reasonable to refer the text instead of copying and owning it.
For very large source files, the parser's syntax map---which contains a
very large number of TrivialLists---was taking an inordinate amount of
memory due to the inefficiency of std::deque. Specifically, a
std::deque containing just one trivial element would allocate 4k of
memory. With the ~120MB SIL output of one of the parse_stdlib tests,
these std::deques would add up to > 6GB of memory, most of which is
wasted.
Replacing the std::deque with a std::vector knocks the memory required
for one of the parse_stdlib tests from > 8GB down closer to 2 GB. The
parser's syntax map is still large (e.g., a 512MB allocation for the
overall vector plus a few hundred MB of raw-syntax data), but not
prohibitively so.
Part of rdar://problem/34771322.
For very large source files, the parser's syntax map---which contains a
very large number of TrivialLists---was taking an inordinate amount of
memory due to the inefficiency of std::deque. Specifically, a
std::deque containing just one trivial element would allocate 4k of
memory. With the ~120MB SIL output of one of the parse_stdlib tests,
these std::deques would add up to > 6GB of memory, most of which is
wasted.
Replacing the std::deque with a std::vector knocks the memory required
for one of the parse_stdlib tests from > 8GB down closer to 2 GB. The
parser's syntax map is still large (e.g., a 512MB allocation for the
overall vector plus a few hundred MB of raw-syntax data), but not
prohibitively so.
Part of rdar://problem/34771322.
