From 55b16959717084884fd4a0cbae6d19e3786c20c7 Mon Sep 17 00:00:00 2001 From: Mike Pall Date: Tue, 8 Dec 2009 19:46:35 +0100 Subject: RELEASE LuaJIT-2.0.0-beta1 --- doc/running.html | 233 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 233 insertions(+) create mode 100644 doc/running.html (limited to 'doc/running.html') diff --git a/doc/running.html b/doc/running.html new file mode 100644 index 00000000..db69578c --- /dev/null +++ b/doc/running.html @@ -0,0 +1,233 @@ + + + +Running LuaJIT + + + + + + + + + +
+Lua +
+ + +
+

+LuaJIT has only a single stand-alone executable, called luajit on +POSIX systems or luajit.exe on Windows. It can be used to run simple +Lua statements or whole Lua applications from the command line. It has an +interactive mode, too. +

+

+Note: the beta test releases only install under the versioned name on +POSIX systems (to avoid overwriting a previous version). You either need +to type luajit-2.0.0-beta1 to start it or create a symlink +with a command like this: +

+
+sudo ln -sf luajit-2.0.0-beta1 /usr/local/bin/luajit
+
+

+Unlike previous versions optimization is turned on by default in +LuaJIT 2.0!
It's no longer necessary to use luajit -O. +

+ +

Command Line Options

+

+The luajit stand-alone executable is just a slightly modified +version of the regular lua stand-alone executable. +It supports the same basic options, too. luajit -h +prints a short list of the available options. Please have a look at the +» Lua manual +for details. +

+

+Two additional options control the behavior of LuaJIT: +

+ +

-j cmd[=arg[,arg...]]

+

+This option performs a LuaJIT control command or activates one of the +loadable extension modules. The command is first looked up in the +jit.* library. If no matching function is found, a module +named jit.<cmd> is loaded and the start() +function of the module is called with the specified arguments (if +any). The space between -j and cmd is optional. +

+

+Here are the available LuaJIT control commands: +

+ +

+The -jv and -jdump commands are extension modules +written in Lua. They are mainly used for debugging the JIT compiler +itself. For a description of their options and output format, please +read the comment block at the start of their source. +They can be found in the lib directory of the source +distribution or installed under the jit directory. By default +this is /usr/local/share/luajit-2.0.0-beta1/jit on POSIX +systems. +

+ +

-O[level]
+-O[+]flag -O-flag
+-Oparam=value

+

+This options allows fine-tuned control of the optimizations used by +the JIT compiler. This is mainly intended for debugging LuaJIT itself. +Please note that the JIT compiler is extremly fast (we are talking +about the microsecond to millisecond range). Disabling optimizations +doesn't have any visible impact on its overhead, but usually generates +code that runs slower. +

+

+The first form sets an optimization level — this enables a +specific mix of optimization flags. -O0 turns off all +optimizations and higher numbers enable more optimizations. Omitting +the level (i.e. just -O) sets the default optimization level, +which is -O3 in the current version. +

+

+The second form adds or removes individual optimization flags. +The third form sets a parameter for the VM or the JIT compiler +to a specific value. +

+

+You can either use this option multiple times (like -Ocse +-O-dce -Ohotloop=10) or separate several settings with a comma +(like -O+cse,-dce,hotloop=10). The settings are applied from +left to right and later settings override earlier ones. You can freely +mix the three forms, but note that setting an optimization level +overrides all earlier flags. +

+

+Here are the available flags and at what optimization levels they +are enabled: +

+ + + + + + + + + + + + + + + + + + + + + + + + +
Flag-O1-O2-O3 
fold•••Constant Folding, Simplifications and Reassociation
cse•••Common-Subexpression Elimination
dce•••Dead-Code Elimination
narrow ••Narrowing of numbers to integers
loop ••Loop Optimizations (code hoisting)
fwd  •Load Forwarding (L2L) and Store Forwarding (S2L)
dse  •Dead-Store Elimination
fuse  •Fusion of operands into instructions
+

+Here are the parameters and their default settings: +

+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
ParameterDefault 
maxtrace1000Max. number of traces in the cache
maxrecord2000Max. number of recorded IR instructions
maxirconst500Max. number of IR constants of a trace
maxside100Max. number of side traces of a root trace
maxsnap100Max. number of snapshots for a trace
hotloop57Number of iterations to detect a hot loop
hotexit10Number of taken exits to start a side trace
tryside4Number of attempts to compile a side trace
instunroll4Max. unroll factor for instable loops
loopunroll7Max. unroll factor for loop ops in side traces
callunroll3Max. unroll factor for pseudo-recursive calls
sizemcode32Size of each machine code area in KBytes (Windows: 64K)
maxmcode512Max. total size of all machine code areas in KBytes
+
+
+ + + -- cgit v1.2.3-55-g6feb