@@ -1,17 +1,22 @@ +2008-08-01 + added: -C (C source generation only) command-line switch to clua. + added: debugging: assert stack checks between statements + fixed: warning from "unused variable `lc_nextra'" + 2008-07-31 + added: -c (compile only) command-line switch to clua. fixed numeric ops with metamethods returning non-numbers fixed: handle "(error object is not a string)" fixed: elseif expression evaluation evaluation order - added: -c (compile only) command-line switch to clua. 2008-07-30 + implemented: ignore shebang lines (#...) + implemented: globals via lua_getfield/lua_setfield/LUA_ENVIRONINDEX + rather than lua_getglobal/lua_setglobal. fixed bug in local function when an upvalue. fixed mlp/gg lexer bug in numeric escapes \ddd in strings. fixed mlp/gg lexer bug in "\\\n" in strings. fixed mlp/gg lexer bug in numbers, e.g. ".1" - implemented: ignore shebang lines (#...) - implemented: globals via lua_getfield/lua_setfield/LUA_ENVIRONINDEX - rather than lua_getglobal/lua_setglobal. 2008-07-29 optimized locals not used as upvalues CHANGES @@ -9,13 +9,11 @@ dist : DIR=lua2c-$(TAG) ; \ (rm -fr $$DIR && \ mkdir $$DIR && \ - mkdir $$DIR/examples && \ mkdir $$DIR/examples-lua && \ mkdir $$DIR/lib && \ mkdir $$DIR/lib/metalua && \ cp README LICENSE CHANGES Makefile lua2c.lua clua \ $$DIR && \ - cp examples/*.lua $$DIR/examples/ && \ cp examples-lua/*.lua $$DIR/examples-lua/ && \ cp lib/*.lua $$DIR/lib/ && \ cp lib/metalua/*.lua $$DIR/lib/metalua/ && \ Makefile @@ -3,14 +3,16 @@ lua2c - converts Lua 5.1 source code to C code. == Description == This utility converts a given Lua source file into an equivalent C -source file containing Lua C API calls. At least, this is true for a -large subset of the Lua language (see limitations below). +source file written in terms of Lua C API calls. At least, this works +for a large subset of the Lua language (see limitations below). + +The compiler is written entirely in Lua, and no build/install is +needed. This project reuses Metalua's gg/mlp parser to convert Lua +source to a Metalua-style[1] AST over which the compiler then +operates. lua2c does not require Metalua itself though since gg/mlp +is bundled in the distribution (patched metalua-0.4.1-rc1) and is +written in pure Lua. -The compiler is written entirely in Lua. This project reuses -Metalua's gg/mlp parser to convert Lua source to a Metalua-style[1] -AST over which the compiler then operates. gg/mlp is bundled in the -distribution (patched metalua-0.4.1-rc1) and is written in pure Lua, -so no build/install is needed. lua2c does not require Metalua itself. == Usage == @@ -22,8 +24,8 @@ which generates a C file to standard output. You may also use the shell script "clua" to compile Lua->C->machine code and execute all in one step. However, you may need to edit the -variables in the file to match your system. This utility invokes the -C compiler. +variables in the file to match your system since this utility invokes +the C compiler. ./clua test/bisect.lua @@ -36,16 +38,16 @@ without running.) == Related Work == - * luac2c - This related effort Hisham Muhammad[2] converts Lua + * luac2c - This related effort by Hisham Muhammad[2] converts Lua bytecodes to C source, whereas this project converts Lua source to C source. luac2c runs into a few similar - limitations as given above. luac2c has remained experimental. - It superseded Luiz Henrique De Figueiredo's very basic but - similarly named lua2c for Lua 4.0.[3] + limitations as given below. luac2c has remained experimental but + superseded Luiz Henrique De Figueiredo's very basic but similarly + named lua2c for Lua 4.0[3]. * luagen++[4] uses C++ expression templates to translate - Lua-like C++ statements to C API calls. The code generation - structure is actually fairly similar to lua2c. + Lua-like C++ statements to C API calls. Some of the code + generation structure is actually fairly similar to lua2c. * Python Pyrex[5] does something similar in Python but has the added goal of lowering the boundary between C and Python @@ -55,16 +57,19 @@ without running.) * Clue by David Given[6] does the opposite: convert C source to Lua source. + * luac + BinToCee allow compilation of Lua source to bytecodes + and/or embedding in a C file. + == Potential Uses == -I think this project not only is nice theoretically to have but +I think this project not only is theoretically nice to have but has a number of potential uses: * Provide another approach of compiling Lua to machine code - (rather than luac + bin2c) + (rather than luac + bin2c). * Streamline the interface between C and Lua code and allow - efficient access to C datatypes from Lua (see Pyrex above) + efficient access to C datatypes from Lua (see Pyrex above). * Compile Lua to optimized C. For example, by statically determining that certain variables are used in a restricted @@ -72,25 +77,27 @@ has a number of potential uses: determining this implicitly by inference), certain code constructs might be simplified to use plain C rather that the Lua C API. This could allow certain Lua code written - with sufficient care to run at native speeds. + with sufficient care to run at native speeds. Since it compiles + to C, it will even work on CPUs where LuaJIT is not available. == Limitations / Status == -lua2c does not currently support coroutines, tail call optimizations, -and functions that normally reject C functions (e.g. setfenv). -These don't have the exact analogue in C. Coroutines might not ever -be supported. However, some solutions might be explored (Coco or -simulating coroutines in C with a lot of ugly code). - -Closures and upvalues are implemented, but creating and accessing -upvalues is somewhat slow. - WARNING: This code passes much of the Lua 5.1 test suite[7] and can compile itself, but the code is new and there can still be errors. In particular, a few language features (e.g. coroutines) are not implemented. See comments in lua2c.lua for details. Please report bugs/patches on the wiki. +lua2c does not currently support coroutines, functions that normally +reject C functions (e.g. setfenv), and possibly tail call +optimizations. Not all of these have the exact analogue in C. +Coroutines might not ever be supported. However, some solutions might +be explored[8][9], including possibly generating code that maintains +the coroutine context in Lua tables. + +Closures and upvalues are implemented, but creating and accessing +upvalues is somewhat slow. + Once the code is more complete/robust, more attention can be given to optimizing the code generation. @@ -102,6 +109,7 @@ The project page is currently http://lua-users.org/wiki/LuaToCee . (c) 2008 David Manura. Licensed under the same terms as Lua (MIT license). See included LICENSE file for full licensing details. +Please post any patches/improvements. == References == @@ -113,3 +121,9 @@ license). See included LICENSE file for full licensing details. * [6] Clue - http://cluecc.sourceforge.net/ * [7] Lua 5.1 test suite - http://www.inf.puc-rio.br/~roberto/lua/lua5.1-tests.tar.gz + * [8] Wikipedia:Coroutine - Implementations for C + http://en.wikipedia.org/wiki/Coroutine#Implementations_for_C + * [9] Coco - http://luajit.org/coco.html Coco - + True C coroutine semantics (used in LuaJIT) + * [10] BinToCee - http://lua-users.org/wiki/BinToCee + README @@ -2,30 +2,50 @@ # # Shell script wrapper to convert Lua to C and optionally # compile and run it. +# +# option -c causes compilation only (no run) +# option -C causes C source generation only (no compile or run) # You may need to change these variables: LUA=lua CC=gcc -#CFLAGS=-g CFLAGS="-O2 -DNDEBUG -Wall -Ilua/src" +#CFLAGS=-g LFLAGS="-Llua/src -llua" +LUA2C="${LUA} lua2c.lua" +#LUA2C="./lua2c" -# option -c causes compilation only (no run) COMPILEONLY= if [ "$1" = "-c" ] then COMPILEONLY=1 shift +elif [ "$1" = "-C" ] +then + COMPILEONLY=2 + shift +fi +if [ "$1" = "" ] +then + echo "usage: clua [options] [filename.lua] ..." + echo " options:" + echo " -c compile only (no run)" + echo " -C generate C source only (no compile or run)" + exit 1 fi LUAFILE=$1 FILENAME=${LUAFILE%.*} CFILE=${FILENAME}.c -${LUA} lua2c.lua ${LUAFILE} > ${CFILE} || exit 1 -${CC} ${CFLAGS} ${CFILE} -o ${FILENAME} ${LFLAGS} || exit 1 +${LUA2C} ${LUAFILE} > ${CFILE} || exit 1 +if [ "$COMPILEONLY" = "2" ] +then + exit 0 +fi -if [ $COMPILEONLY ] +${CC} ${CFLAGS} ${CFILE} -o ${FILENAME} ${LFLAGS} || exit 1 +if [ "$COMPILEONLY" = "1" ] then exit 0 fi clua @@ -8,20 +8,18 @@ -- Unimplemented Lua language features: -- - deprecated old style vararg (arg) table inside vararg functions -- (LUA_COMPAT_VARARG) --- - debug.getinfo(f, 'n').name for functions implemented in C --- - setfenv does not permit functions implemented in C +-- - debug.getinfo(f, 'n').name for C-based functions +-- - setfenv does not permit C-based functions -- - how well do tail call optimizations work? --- - how to handle coroutines? --- Coco useful here? [ http://luajit.org/coco.html ] +-- - how to handle coroutines? (see README) -- Note: A few things (coroutines) might remain -- unimplemented--see README file file for details. -- -- Possible improvements: --- - gcc warning: unused variable `lc_nextra' --- - Literal numbers are rendered as C integers literals (e.g. 123) --- rather than C double literals (eg. 123.0). Therefore, large values --- can give gcc warnings such as 'warning: integer constant is too --- large for "long" type'). +-- - Fix: large numerical literals can give gcc warnings such as +-- 'warning: integer constant is too large for "long" type'). +-- Literal numbers are rendered as C integers literals (e.g. 123) +-- rather than C double literals (eg. 123.0). -- - Generated C functions could be named based on the Lua function -- name. -- - improved debug tracebacks on exceptions @@ -31,6 +29,7 @@ -- -- http://lua-users.org/wiki/LuaToCee -- (c) 2008 David Manura. Licensed in the same terms as Lua (MIT license). +-- See included LICENSE file for full licensing details. -- Please post any patches/improvements. -- @@ -124,6 +123,7 @@ local currentscope = {['.closurelevel'] = 0} -- Information on function currently being compiled. local funcinfo = {is_vararg=false, nformalparams=0, is_lc_nextra_used=false, is_lc_nactualargs_used=false, + is_lc_nextra_used_debug=false, is_lc_nactualargs_used_debug=false, idxtopmax = 0 --old: outervars={} } @@ -280,8 +280,7 @@ local function realidx(idx) (tag(idxreal) == 'Id' or idxreal > funcinfo.nformalparams) then if tag(idx) == 'Upval' then - idx = {tag='Upval', C.Op('+', idxreal, C.Id'lc_nextra'), idx[2], idx[3]} - funcinfo.is_lc_nextra_used = true + -- no adjustment else idx = C.Op('+', idx, C.Id'lc_nextra') funcinfo.is_lc_nextra_used = true @@ -311,7 +310,7 @@ local function adjustidx(offset, idx) if type(idx) == 'table' or idx > 0 then return idx else -- relative stack index or pseudoindex - -- FIX:pseudoindices not supported + -- FIX:pseudoindices not supported? return idx + offset + 1 end end @@ -813,6 +812,7 @@ local function genfunctiondef(ast, ismain) local nformalargs = #params_ast - (has_vararg and 1 or 0) funcinfo = {is_vararg = has_vararg, nformalparams = nformalargs, is_lc_nextra_used = false, is_lc_nactualargs_used=false, + is_lc_nextra_used_debug = false, is_lc_nactualargs_used_debug=false, idxtopmax = 0 --old: outervars = currentscope } @@ -890,13 +890,25 @@ local function genfunctiondef(ast, ismain) -- (important for genexpr of `Id) if funcinfo.is_lc_nextra_used then funcinfo.is_lc_nactualargs_used = true + elseif funcinfo.is_lc_nextra_used_debug then + funcinfo.is_lc_nactualargs_used_debug = true end + if funcinfo.is_lc_nactualargs_used then bodypre_cast:append(C.LetInt('lc_nactualargs', C.lua_gettop())) + elseif funcinfo.is_lc_nactualargs_used_debug then + bodypre_cast:append(C.C'#ifndef NDEBUG') + bodypre_cast:append(C.LetInt('lc_nactualargs', C.lua_gettop())) + bodypre_cast:append(C.C'#endif') end if funcinfo.is_lc_nextra_used then bodypre_cast:append(C.LetInt('lc_nextra', C.Op('-', C.Id'lc_nactualargs', C.Id'lc_nformalargs'))) + elseif funcinfo.is_lc_nextra_used_debug then + bodypre_cast:append(C.C'#ifndef NDEBUG') + bodypre_cast:append(C.LetInt('lc_nextra', + C.Op('-', C.Id'lc_nactualargs', C.Id'lc_nformalargs'))) + bodypre_cast:append(C.C'#endif') end else bodypre_cast:append(C.lua_settop(#params_ast)) @@ -1820,9 +1832,18 @@ function genblock(ast) for _,stat_ast in ipairs(ast) do cast:append(genstatement(stat_ast)) - --FIX:DEBUG: funcinfo.is_lc_nextra_used = true - --cast:append(C.C([[ assert(lua_gettop(L) - lc_nextra == ]] - -- .. idxtop .. [[);]])) + -- DEBUG + if true then + if funcinfo.is_vararg then + funcinfo.is_lc_nextra_used_debug = true + end + if not is_created['assert.h'] then + append_array(cast.pre, {C.Include'<assert.h>'}) + is_created['assert.h'] = true + end + cast:append(C.C(string.format([[assert(lua_gettop(L) %s== %d);]], + funcinfo.is_lc_nextra_used_debug and "- lc_nextra " or "", idxtop))) + end end return cast @@ -2251,7 +2272,7 @@ if not src_filename then os.exit(1) end -local src_file = io.open (src_filename, 'r') +local src_file = assert(io.open (src_filename, 'r')) src = src_file:read '*a'; src_file:close() src = src:gsub('^#[^\r\n]*', '') -- remove any shebang lua2c.lua examples/test1.lua 8ef69e1343c51e0fa507f07d5507b8c4f467395b David Manura dm.git@math2.org http://github.com/davidm/lua2c/commit/f4cc79b1e0d2efa85f33d75586c69efe336a161d f4cc79b1e0d2efa85f33d75586c69efe336a161d 2008-07-31T20:50:31-07:00 2008-07-31T20:50:31-07:00 2008-08-01 added: -C (C source generation only) command-line switch to clua. added: debugging: assert stack checks between statements fixed: warning from "unused variable `lc_nextra'" Imported from lua2c-0.2-20080801.tar.gz. 9eb6d68d90394187af7ea09f469ad512665bc455 David Manura dm.git@math2.org