Closed agladysh closed 13 years ago
agladysh
commented
13 years ago Also, I find these accesses to zmq constant fields a bit strange — given that require 'zmq' is nowhere to be found in this code. This probably works due to some implementation details in your FFI bindings generator, but I would at least leave a comment there, describing what is going on.
Neopallium
commented
13 years ago Fixed incorrect use of global for ud_obj variable. Also localized some of the other global access that needed it. Most of those global accesses are only during the loading of the zmq FFI bindings and there is no need to localize them at the top of the file.
The FFI bindings over-write part of the normal Lua C API bindings, so those constants are define in the C code before the FFI bindings are loaded.
agladysh
commented
13 years ago Thank you, fix confirmed!
By analyzing
luac -loutput, I found one variable that is regularly accessed via{S,G}ETGLOBALin lua-zmq FFI bindings —ud_obj:31 [88] SETGLOBAL 4 -8 ; ud_obj 35 [89] GETGLOBAL 6 -8 ; ud_obj 39 [94] GETGLOBAL 5 -8 ; ud_obj 8 [161] SETGLOBAL 3 -2 ; ud_obj 12 [162] GETGLOBAL 5 -2 ; ud_obj 20 [166] GETGLOBAL 4 -2 ; ud_objNumber in square brackets is line number in
zmq.dump_ffi()output.Note that this may be a false positive if you prepend some kind of header with
local ud_objdeclaration before loading this code.Also, a small nitpicking observation: there is a lot of non-aliased global variables used (see full dump below). It is a better style to alias all this stuff to locals on the top of the file — this really helps if code is being run inside sandboxed environment. (Not that I plan to do so with zmq right now, but anyway.)
$ luajit2 -lzmq -e 'io.stdout:write(zmq:dump_ffi())' | tee zmq_ffi_dump.lua | luac -l -o /dev/null - | grep ETGLOBAL 1 [2] GETGLOBAL 0 -1 ; pcall 2 [2] GETGLOBAL 1 -2 ; require 9 [9] GETGLOBAL 5 -4 ; bit 11 [10] GETGLOBAL 6 -6 ; debug 13 [11] GETGLOBAL 7 -6 ; debug 23 [48] GETGLOBAL 13 -8 ; setmetatable 107 [390] GETGLOBAL 37 -16 ; pairs 111 [391] GETGLOBAL 42 -17 ; type 124 [396] GETGLOBAL 37 -16 ; pairs 228 [632] GETGLOBAL 44 -20 ; zmq 231 [633] GETGLOBAL 44 -20 ; zmq 234 [634] GETGLOBAL 44 -20 ; zmq 237 [635] GETGLOBAL 44 -20 ; zmq 240 [636] GETGLOBAL 44 -20 ; zmq 243 [637] GETGLOBAL 44 -20 ; zmq 246 [638] GETGLOBAL 44 -20 ; zmq 249 [639] GETGLOBAL 44 -20 ; zmq 252 [640] GETGLOBAL 44 -20 ; zmq 255 [641] GETGLOBAL 44 -20 ; zmq 258 [642] GETGLOBAL 44 -20 ; zmq 261 [643] GETGLOBAL 44 -20 ; zmq 264 [644] GETGLOBAL 44 -20 ; zmq 267 [645] GETGLOBAL 44 -20 ; zmq 270 [646] GETGLOBAL 44 -20 ; zmq 273 [647] GETGLOBAL 44 -20 ; zmq 276 [648] GETGLOBAL 44 -20 ; zmq 279 [649] GETGLOBAL 44 -20 ; zmq 284 [653] GETGLOBAL 46 -16 ; pairs 12 [56] GETGLOBAL 3 -3 ; error 16 [56] GETGLOBAL 7 -7 ; type 23 [84] SETGLOBAL 6 -7 ; type 31 [88] SETGLOBAL 4 -8 ; ud_obj 35 [89] GETGLOBAL 6 -8 ; ud_obj 39 [94] GETGLOBAL 5 -8 ; ud_obj 13 [106] GETGLOBAL 5 -5 ; tonumber 23 [120] SETGLOBAL 6 -7 ; type 24 [124] GETGLOBAL 4 -8 ; tonumber 12 [147] GETGLOBAL 3 -3 ; error 16 [147] GETGLOBAL 7 -7 ; type 8 [161] SETGLOBAL 3 -2 ; ud_obj 12 [162] GETGLOBAL 5 -2 ; ud_obj 20 [166] GETGLOBAL 4 -2 ; ud_obj 3 [266] GETGLOBAL 1 -2 ; setmetatable 3 [298] GETGLOBAL 1 -2 ; setmetatable 3 [330] GETGLOBAL 1 -2 ; setmetatable 3 [362] GETGLOBAL 1 -2 ; setmetatable 24 [503] GETGLOBAL 5 -5 ; error 23 [540] GETGLOBAL 4 -5 ; error 11 [670] GETGLOBAL 8 -3 ; tostring 50 [715] GETGLOBAL 7 -8 ; tonumber 40 [900] GETGLOBAL 6 -10 ; tonumber 1 [984] GETGLOBAL 2 -1 ; type 17 [990] GETGLOBAL 3 -6 ; error