Hi, Kevin Ryde <[EMAIL PROTECTED]> writes:
> Speaking of scm_getc ... I've wondered for a while if some of the low > level reading funcs ought to be looking directly into the read buffer > instead of making a call to scm_getc for every char. My experience > has usually been that a function call per character is very much to be > avoided if performance on sizeable input matters. You are right: `scm_getc ()' _is_ a performance bottleneck, one function call for a single memory read (which is the common case when the port is buffered) is way too much---`scm_getc ()' often shows up in the top 10 in Gprof's flat profile. The whole point of having a buffer in a publicly-exposed struct is to avoid function call overhead when accessing it. Thus, `scm_getc ()' should be inlined. (You might have read that Guile-Reader is noticeably faster than `scm_read ()'. One of the reasons for this is that it inlines `scm_getc ()' in the generated lightning code.) Unfortunately, the machinery in `inline.h' makes it quite inconvenient to add inline functions, and forces us to put all of them in a single file. GMP has a similar but slightly "cleaner" mechanism, which maybe we could build upon to improve ours. There are definitely a number of functions candidate for inlining in Guile, typically functions that only execute a handful of instructions. Thanks, Ludovic. _______________________________________________ Guile-devel mailing list Guile-devel@gnu.org http://lists.gnu.org/mailman/listinfo/guile-devel
