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Revision: 1.2
Committed: Fri Mar 10 20:54:34 2006 UTC (18 years, 3 months ago) by root
Branch: MAIN
Changes since 1.1: +49 -124 lines
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File Contents

# Content
1 NAME
2 Faster - do some things faster
3
4 SYNOPSIS
5 use Faster;
6
7 perl -MFaster ...
8
9 DESCRIPTION
10 This module implements a very simple-minded JIT. It works by more or
11 less translating every function it sees into a C program, compiling it
12 and then replacing the function by the compiled code.
13
14 As a result, startup times are immense, as every function might lead to
15 a full-blown compilation.
16
17 The speed improvements are also not great, you can expect 20% or so on
18 average, for code that runs very often.
19
20 Faster is in the early stages of development. Due to its design its
21 relatively safe to use (it will either work or simply slowdown the
22 program immensely, but rarely cause bugs).
23
24 Usage is very easy, just "use Faster" and every function called from
25 then on will be compiled.
26
27 Right now, Faster will leave ltos of *.c, *.o and *.so files in /tmp,
28 and it will even create those temporary files in an insecure manner, so
29 watch out.
30
31 BUGS/LIMITATIONS
32 Perl will check much less often for asynchronous signals in
33 Faster-compiled code. It tries to check on every function call, loop
34 iteration and every I/O operator, though.
35
36 The following things will disable Faster. If you manage to enable them
37 at runtime, bad things will happen.
38
39 enabled tainting
40 enabled debugging
41
42 This will dramatically reduce Faster's performance:
43
44 threads (but you don't care about speed if you use threads anyway)
45
46 These constructs will force the use of the interpreter as soon as they
47 are being executed, for the rest of the currently executed:
48
49 .., ... (flipflop operators)
50 goto
51 next, redo (but not well-behaved last's)
52 eval
53 require
54 any use of formats
55
56 AUTHOR
57 Marc Lehmann <schmorp@schmorp.de>
58 http://home.schmorp.de/
59