Re: benchmarking Flex practices

I wrote:

> I'll look for other rules that could be more
> easily optimized, but I'm not terribly optimistic.

I found a possible other way to bring the size of the transition table
under 32k entries while keeping the existing no-backup rules in place:
Replace the "quotecontinue" rule with a new state. In the attached
draft patch, when Flex encounters a quote while inside any kind of
quoted string, it saves the current state and enters %xqs (think
'quotestop'). If it then sees {whitespace_with_newline}{quote}, it
reenters the previous state and continues to slurp the string,
otherwise, it throws back everything and returns the string it just
exited. Doing it this way is a bit uglier, but with some extra
commentary it might not be too bad.

The array is now 30883 entries. That's still a bit close for comfort,
but shrinks the binary by 171kB on Linux x86-64 with Flex 2.6.4. The
bad news is I have these baffling backup states in my new rules:

State #133 is non-accepting -
associated rule line numbers:
551 554 564
out-transitions: [ \000-\377 ]
jam-transitions: EOF []

State #162 is non-accepting -
associated rule line numbers:
551 554 564
out-transitions: [ \000-\377 ]
jam-transitions: EOF []

2 backing up (non-accepting) states.

I already explicitly handle EOF, so I don't know what it's trying to
tell me. If it can be fixed while keeping the array size, I'll do
performance tests.

--
John Naylor https://www.2ndQuadrant.com/
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