I forgot to reply to this specific point:
Me: Note also that LLVM is very unlikely to be able to able to optimise away any of the get_context() calls in the XS code.
You: Why? If they can be #defined away, why can they not be optimised away?
get_context() requires (on threaded builds) to retrieve a value from thread-local storage.
This requires (at least the last time I looked in the linux pthreads library) the current stack pointer to be compared against the stack range allocated to each current thread, to determine which thread we are. I'd be amazed if LLVM could determine that the value won't change between calls!
PERL_NO_GET_CONTEXT causes the value (the address of the current perl interpreter) to be passed as an extra argument to each XS function, rather than calling get_context() every time a function in the perl library needs to be called.
Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
Read Where should I post X? if you're not absolutely sure you're posting in the right place.
Please read these before you post! —
Posts may use any of the Perl Monks Approved HTML tags:
You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
- a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
Link using PerlMonks shortcuts! What shortcuts can I use for linking?
See Writeup Formatting Tips and other pages linked from there for more info.
| & || & |
| < || < |
| > || > |
| [ || [ |
| ] || ] ||