+This is a list of changes between the released versions of LuaJIT.
+The current development version is LuaJIT 2.0.0-beta9.
+The current stable version is LuaJIT 1.1.7.
+
+Please check the +» Online Change History +to see whether newer versions are available. +
+ +
+
+
+LuaJIT 2.0.0-beta9 — 2011-12-14
+-
+
- New features:
+
-
+
- PPC port of LuaJIT is complete. Default is the dual-number port +(usually faster). Single-number port selectable via src/Makefile +at build time. +
- Add FFI callback support. +
- Extend -b to generate .c, .h or .obj/.o +files with embedded bytecode. +
- Allow loading embedded bytecode with require(). +
- From Lua 5.2: Change to '\z' escape. Reject undefined escape +sequences. +
+ - Correctness and completeness:
+
-
+
- Fix OSX 10.7 build. Fix install_name and versioning on OSX. +
- Fix iOS build. +
- Install dis_arm.lua, too. +
- Mark installed shared library as executable. +
- Add debug option to msvcbuild.bat and improve error handling. +
- Fix data-flow analysis for iterators. +
- Fix forced unwinding triggered by external unwinder. +
- Record missing for loop slot loads (return to lower frame). +
- Always use ANSI variants of Windows system functions. +
- Fix GC barrier for multi-result table constructor (TSETM). +
- Fix/add various FOLD rules. +
- Add potential PHI for number conversions due to type instability. +
- Do not eliminate PHIs only referenced from other PHIs. +
- Correctly anchor implicit number to string conversions in Lua/C API. +
- Fix various stack limit checks. +
- x64: Use thread-safe exceptions for external unwinding (GCC platforms). +
- x64: Fix result type of cdata index conversions. +
- x64: Fix math.random() and bit.bswap() code generation. +
- x64: Fix lightuserdata comparisons. +
- x64: Always extend stack-passed arguments to pointer size. +
- ARM: Many fixes to code generation backend. +
- PPC/e500: Fix dispatch for binop metamethods. +
- PPC/e500: Save/restore condition registers when entering/leaving the VM. +
- PPC/e500: Fix write barrier in stores of strings to upvalues. +
+ - FFI library:
+
-
+
- Fix C comment parsing. +
- Fix snapshot optimization for cdata comparisons. +
- Fix recording of const/enum lookups in namespaces. +
- Fix call argument and return handling for I8/U8/I16/U16 types. +
- Fix unfused loads of float fields. +
- Fix ffi.string() recording. +
- Save GetLastError() around ffi.load() and symbol +resolving, too. +
- Improve ld script detection in ffi.load(). +
- Record loads/stores to external variables in namespaces. +
- Compile calls to stdcall, fastcall and vararg functions. +
- Treat function ctypes like pointers in comparisons. +
- Resolve __call metamethod for pointers, too. +
- Record C function calls with bool return values. +
- Record ffi.errno(). +
- x86: Fix number to uint32_t conversion rounding. +
- x86: Fix 64 bit arithmetic in assembler backend. +
- x64: Fix struct-by-value calling conventions. +
- ARM: Ensure invocation of SPLIT pass for float conversions. +
+ - Structural and performance enhancements:
+
-
+
- Display trace types with -jv and -jdump. +
- Record isolated calls. But prefer recording loops over calls. +
- Specialize to prototype for non-monomorphic functions. Solves the +trace-explosion problem for closure-heavy programming styles. +
- Always generate a portable vmdef.lua. Easier for distros. +
+
LuaJIT 2.0.0-beta8 — 2011-06-23
+-
+
- New features:
+
-
+
- Soft-float ARM port of LuaJIT is complete. +
- Add support for bytecode loading/saving and -b command line +option. +
- From Lua 5.2: __len metamethod for tables +(disabled by default). +
+ - Correctness and completeness:
+
-
+
- ARM: Misc. fixes for interpreter. +
- x86/x64: Fix bit.* argument checking in interpreter. +
- Catch early out-of-memory in memory allocator initialization. +
- Fix data-flow analysis for paths leading to an upvalue close. +
- Fix check for missing arguments in string.format(). +
- Fix Solaris/x86 build (note: not a supported target). +
- Fix recording of loops with instable directions in side traces. +
- x86/x64: Fix fusion of comparisons with u8/u16 +XLOAD. +
- x86/x64: Fix register allocation for variable shifts. +
+ - FFI library:
+
-
+
- Add ffi.errno(). Save errno/GetLastError() +around allocations etc. +
- Fix __gc for VLA/VLS cdata objects. +
- Fix recording of casts from 32 bit cdata pointers to integers. +
- tonumber(cdata) returns nil for non-numbers. +
- Show address pointed to for tostring(pointer). +
- Print NULL pointers as "cdata<... *>: NULL". +
- Support __tostring metamethod for pointers to structs, too. +
+ - Structural and performance enhancements:
+
-
+
- More tuning for loop unrolling heuristics. +
- Flatten and compress in-memory debug info (saves ~70%). +
+
LuaJIT 2.0.0-beta7 — 2011-05-05
+-
+
- New features:
+
-
+
- ARM port of the LuaJIT interpreter is complete. +
- FFI library: Add ffi.gc(), ffi.metatype(), +ffi.istype(). +
- FFI library: Resolve ld script redirection in ffi.load(). +
- From Lua 5.2: package.searchpath(), fp:read("*L"), +load(string). +
- From Lua 5.2, disabled by default: empty statement, +table.unpack(), modified coroutine.running(). +
+ - Correctness and completeness:
+
-
+
- FFI library: numerous fixes. +
- Fix type mismatches in store-to-load forwarding. +
- Fix error handling within metamethods. +
- Fix table.maxn(). +
- Improve accuracy of x^-k on x64. +
- Fix code generation for Intel Atom in x64 mode. +
- Fix narrowing of POW. +
- Fix recording of retried fast functions. +
- Fix code generation for bit.bnot() and multiplies. +
- Fix error location within cpcall frames. +
- Add workaround for old libgcc unwind bug. +
- Fix lua_yield() and getmetatable(lightuserdata) on x64. +
- Misc. fixes for PPC/e500 interpreter. +
- Fix stack slot updates for down-recursion. +
+ - Structural and performance enhancements:
+
-
+
- Add dual-number mode (int/double) for the VM. Enabled for ARM. +
- Improve narrowing of arithmetic operators and for loops. +
- Tune loop unrolling heuristics and increase trace recorder limits. +
- Eliminate dead slots in snapshots using bytecode data-flow analysis. +
- Avoid phantom stores to proxy tables. +
- Optimize lookups in empty proxy tables. +
- Improve bytecode optimization of and/or operators. +
+
LuaJIT 2.0.0-beta6 — 2011-02-11
+-
+
- New features:
+
-
+
- PowerPC/e500v2 port of the LuaJIT interpreter is complete. +
- Various minor features from Lua 5.2: Hex escapes in literals, +'\*' escape, reversible string.format("%q",s), +"%g" pattern, table.sort checks callbacks, +os.exit(status|true|false[,close]). +
- Lua 5.2 __pairs and __ipairs metamethods +(disabled by default). +
- Initial release of the FFI library. +
+ - Correctness and completeness:
+
-
+
- Fix string.format() for non-finite numbers. +
- Fix memory leak when compiled to use the built-in allocator. +
- x86/x64: Fix unnecessary resize in TSETM bytecode. +
- Fix various GC issues with traces and jit.flush(). +
- x64: Fix fusion of indexes for array references. +
- x86/x64: Fix stack overflow handling for coroutine results. +
- Enable low-2GB memory allocation on FreeBSD/x64. +
- Fix collectgarbage("count") result if more than 2GB is in use. +
- Fix parsing of hex floats. +
- x86/x64: Fix loop branch inversion with trailing +HREF+NE/EQ. +
- Add jit.os string. +
- coroutine.create() permits running C functions, too. +
- Fix OSX build to work with newer ld64 versions. +
- Fix bytecode optimization of and/or operators. +
+ - Structural and performance enhancements:
+
-
+
- Emit specialized bytecode for pairs()/next(). +
- Improve bytecode coalescing of nil constants. +
- Compile calls to vararg functions. +
- Compile select(). +
- Improve alias analysis, esp. for loads from allocations. +
- Tuning of various compiler heuristics. +
- Refactor and extend IR conversion instructions. +
- x86/x64: Various backend enhancements related to the FFI. +
- Add SPLIT pass to split 64 bit IR instructions for 32 bit CPUs. +
+
LuaJIT 2.0.0-beta5 — 2010-08-24
+-
+
- Correctness and completeness:
+
-
+
- Fix trace exit dispatch to function headers. +
- Fix Windows and OSX builds with LUAJIT_DISABLE_JIT. +
- Reorganize and fix placement of generated machine code on x64. +
- Fix TNEW in x64 interpreter. +
- Do not eliminate PHIs for values only referenced from side exits. +
- OS-independent canonicalization of strings for non-finite numbers. +
- Fix string.char() range check on x64. +
- Fix tostring() resolving within print(). +
- Fix error handling for next(). +
- Fix passing of constant arguments to external calls on x64. +
- Fix interpreter argument check for two-argument SSE math functions. +
- Fix C frame chain corruption caused by lua_cpcall(). +
- Fix return from pcall() within active hook. +
+ - Structural and performance enhancements:
+
-
+
- Replace on-trace GC frame syncing with interpreter exit. +
- Improve hash lookup specialization by not removing dead keys during GC. +
- Turn traces into true GC objects. +
- Avoid starting a GC cycle immediately after library init. +
- Add weak guards to improve dead-code elimination. +
- Speed up string interning. +
+
LuaJIT 2.0.0-beta4 — 2010-03-28
+-
+
- Correctness and completeness:
+
-
+
- Fix precondition for on-trace creation of table keys. +
- Fix {f()} on x64 when table is resized. +
- Fix folding of ordered comparisons with same references. +
- Fix snapshot restores for multi-result bytecodes. +
- Fix potential hang when recording bytecode with nested closures. +
- Fix recording of getmetatable(), tonumber() and bad argument types. +
- Fix SLOAD fusion across returns to lower frames. +
+ - Structural and performance enhancements:
+
-
+
- Add array bounds check elimination. -Oabc is enabled by default. +
- More tuning for x64, e.g. smaller table objects. +
+
LuaJIT 2.0.0-beta3 — 2010-03-07
+-
+
- LuaJIT x64 port:
+
-
+
- Port integrated memory allocator to Linux/x64, Windows/x64 and OSX/x64. +
- Port interpreter and JIT compiler to x64. +
- Port DynASM to x64. +
- Many 32/64 bit cleanups in the VM. +
- Allow building the interpreter with either x87 or SSE2 arithmetics. +
- Add external unwinding and C++ exception interop (default on x64). +
+ - Correctness and completeness:
+
-
+
- Fix constructor bytecode generation for certain conditional values. +
- Fix some cases of ordered string comparisons. +
- Fix lua_tocfunction(). +
- Fix cutoff register in JMP bytecode for some conditional expressions. +
- Fix PHI marking algorithm for references from variant slots. +
- Fix package.cpath for non-default PREFIX. +
- Fix DWARF2 frame unwind information for interpreter on OSX. +
- Drive the GC forward on string allocations in the parser. +
- Implement call/return hooks (zero-cost if disabled). +
- Implement yield from C hooks. +
- Disable JIT compiler on older non-SSE2 CPUs instead of aborting. +
+ - Structural and performance enhancements:
+
-
+
- Compile recursive code (tail-, up- and down-recursion). +
- Improve heuristics for bytecode penalties and blacklisting. +
- Split CALL/FUNC recording and clean up fast function call semantics. +
- Major redesign of internal function call handling. +
- Improve FOR loop const specialization and integerness checks. +
- Switch to pre-initialized stacks. Avoid frame-clearing. +
- Colocation of prototypes and related data: bytecode, constants, debug info. +
- Cleanup parser and streamline bytecode generation. +
- Add support for weak IR references to register allocator. +
- Switch to compressed, extensible snapshots. +
- Compile returns to frames below the start frame. +
- Improve alias analysis of upvalues using a disambiguation hash value. +
- Compile floor/ceil/trunc to SSE2 helper calls or SSE4.1 instructions. +
- Add generic C call handling to IR and backend. +
- Improve KNUM fuse vs. load heuristics. +
- Compile various io.*() functions. +
- Compile math.sinh(), math.cosh(), math.tanh() +and math.random(). +
+
LuaJIT 2.0.0-beta2 — 2009-11-09
+-
+
- Reorganize build system. Build static+shared library on POSIX. +
- Allow C++ exception conversion on all platforms +using a wrapper function. +
- Automatically catch C++ exceptions and rethrow Lua error +(DWARF2 only). +
- Check for the correct x87 FPU precision at strategic points. +
- Always use wrappers for libm functions. +
- Resurrect metamethod name strings before copying them. +
- Mark current trace, even if compiler is idle. +
- Ensure FILE metatable is created only once. +
- Fix type comparisons when different integer types are involved. +
- Fix getmetatable() recording. +
- Fix TDUP with dead keys in template table. +
- jit.flush(tr) returns status. +Prevent manual flush of a trace that's still linked. +
- Improve register allocation heuristics for invariant references. +
- Compile the push/pop variants of table.insert() and +table.remove(). +
- Compatibility with MSVC link /debug. +
- Fix lua_iscfunction(). +
- Fix math.random() when compiled with -fpic (OSX). +
- Fix table.maxn(). +
- Bump MACOSX_DEPLOYMENT_TARGET to 10.4 +
- luaL_check*() and luaL_opt*() now support
+negative arguments, too.
+This matches the behavior of Lua 5.1, but not the specification.
+
LuaJIT 2.0.0-beta1 — 2009-10-31
+-
+
- This is the first public release of LuaJIT 2.0. +
- The whole VM has been rewritten from the ground up, so there's +no point in listing differences over earlier versions. +
+
+
+LuaJIT 1.1.7 — 2011-05-05
+-
+
- Added fixes for the +» currently known bugs in Lua 5.1.4. +
LuaJIT 1.1.6 — 2010-03-28
+-
+
- Added fixes for the +» currently known bugs in Lua 5.1.4. +
- Removed wrong GC check in jit_createstate(). +Thanks to Tim Mensch. +
- Fixed bad assertions while compiling table.insert() and +table.remove(). +
LuaJIT 1.1.5 — 2008-10-25
+-
+
- Merged with Lua 5.1.4. Fixes all +» known bugs in Lua 5.1.3. +
LuaJIT 1.1.4 — 2008-02-05
+-
+
- Merged with Lua 5.1.3. Fixes all +» known bugs in Lua 5.1.2. +
- Fixed possible (but unlikely) stack corruption while compiling +k^x expressions. +
- Fixed DynASM template for cmpss instruction. +
LuaJIT 1.1.3 — 2007-05-24
+-
+
- Merged with Lua 5.1.2. Fixes all +» known bugs in Lua 5.1.1. +
- Merged pending Lua 5.1.x fixes: "return -nil" bug, spurious count hook call. +
- Remove a (sometimes) wrong assertion in luaJIT_findpc(). +
- DynASM now allows labels for displacements and .aword. +
- Fix some compiler warnings for DynASM glue (internal API change). +
- Correct naming for SSSE3 (temporarily known as SSE4) in DynASM and x86 disassembler. +
- The loadable debug modules now handle redirection to stdout +(e.g. -j trace=-). +
LuaJIT 1.1.2 — 2006-06-24
+-
+
- Fix MSVC inline assembly: use only local variables with +lua_number2int(). +
- Fix "attempt to call a thread value" bug on Mac OS X: +make values of consts used as lightuserdata keys unique +to avoid joining by the compiler/linker. +
LuaJIT 1.1.1 — 2006-06-20
+-
+
- Merged with Lua 5.1.1. Fixes all +» known bugs in Lua 5.1. +
- Enforce (dynamic) linker error for EXE/DLL version mismatches. +
- Minor changes to DynASM: faster pre-processing, smaller encoding +for some immediates. +
+This release is in sync with Coco 1.1.1 (see the +» Coco Change History). +
+ +LuaJIT 1.1.0 — 2006-03-13
+-
+
- Merged with Lua 5.1 (final). + +
- New JIT call frame setup:
+
-
+
- The C stack is kept 16 byte aligned (faster). +Mandatory for Mac OS X on Intel, too. +
- Faster calling conventions for internal C helper functions. +
- Better instruction scheduling for function prologue, OP_CALL and +OP_RETURN. +
+
+ - Miscellaneous optimizations:
+
-
+
- Faster loads of FP constants. Remove narrow-to-wide store-to-load +forwarding stalls. +
- Use (scalar) SSE2 ops (if the CPU supports it) to speed up slot moves +and FP to integer conversions. +
- Optimized the two-argument form of OP_CONCAT (a..b). +
- Inlined OP_MOD (a%b). +With better accuracy than the C variant, too. +
- Inlined OP_POW (a^b). Unroll x^k or +use k^x = 2^(log2(k)*x) or call pow(). +
+
+ - Changes in the optimizer:
+
-
+
- Improved hinting for table keys derived from table values +(t1[t2[x]]). +
- Lookup hinting now works with arbitrary object types and +supports index chains, too. +
- Generate type hints for arithmetic and comparison operators, +OP_LEN, OP_CONCAT and OP_FORPREP. +
- Remove several hint definitions in favour of a generic COMBINE hint. +
- Complete rewrite of jit.opt_inline module +(ex jit.opt_lib). +
+
+ - Use adaptive deoptimization:
+
-
+
- If runtime verification of a contract fails, the affected +instruction is recompiled and patched on-the-fly. +Regular programs will trigger deoptimization only occasionally. +
- This avoids generating code for uncommon fallback cases +most of the time. Generated code is up to 30% smaller compared to +LuaJIT 1.0.3. +
- Deoptimization is used for many opcodes and contracts:
+
-
+
- OP_CALL, OP_TAILCALL: type mismatch for callable. +
- Inlined calls: closure mismatch, parameter number and type mismatches. +
- OP_GETTABLE, OP_SETTABLE: table or key type and range mismatches. +
- All arithmetic and comparison operators, OP_LEN, OP_CONCAT, +OP_FORPREP: operand type and range mismatches. +
+ - Complete redesign of the debug and traceback info +(bytecode ↔ mcode) to support deoptimization. +Much more flexible and needs only 50% of the space. +
- The modules jit.trace, jit.dumphints and +jit.dump handle deoptimization. +
+
+ - Inlined many popular library functions
+(for commonly used arguments only):
+
-
+
- Most math.* functions (the 18 most used ones) +[2x-10x faster]. +
- string.len, string.sub and string.char +[2x-10x faster]. +
- table.insert, table.remove and table.getn +[3x-5x faster]. +
- coroutine.yield and coroutine.resume +[3x-5x faster]. +
- pairs, ipairs and the corresponding iterators +[8x-15x faster]. +
+
+ - Changes in the core and loadable modules and the stand-alone executable:
+
-
+
- Added jit.version, jit.version_num +and jit.arch. +
- Reorganized some internal API functions (jit.util.*mcode*). +
- The -j dump output now shows JSUB names, too. +
- New x86 disassembler module written in pure Lua. No dependency +on ndisasm anymore. Flexible API, very compact (500 lines) +and complete (x87, MMX, SSE, SSE2, SSE3, SSSE3, privileged instructions). +
- luajit -v prints the LuaJIT version and copyright +on a separate line. +
+
+ - Added SSE, SSE2, SSE3 and SSSE3 support to DynASM. +
- Miscellaneous doc changes. Added a section about +embedding LuaJIT. +
+This release is in sync with Coco 1.1.0 (see the +» Coco Change History). +
+
+
+LuaJIT 1.0.3 — 2005-09-08
+-
+
- Even more docs. +
- Unified closure checks in jit.*. +
- Fixed some range checks in jit.util.*. +
- Fixed __newindex call originating from jit_settable_str(). +
- Merged with Lua 5.1 alpha (including early bug fixes). +
+This is the first public release of LuaJIT. +
+ +LuaJIT 1.0.2 — 2005-09-02
+-
+
- Add support for flushing the Valgrind translation cache
+(MYCFLAGS= -DUSE_VALGRIND).
+ - Add support for freeing executable mcode memory to the mmap()-based +variant for POSIX systems. +
- Reorganized the C function signature handling in +jit.opt_lib. +
- Changed to index-based hints for inlining C functions. +Still no support in the backend for inlining. +
- Hardcode HEAP_CREATE_ENABLE_EXECUTE value if undefined. +
- Misc. changes to the jit.* modules. +
- Misc. changes to the Makefiles. +
- Lots of new docs. +
- Complete doc reorg. +
+Not released because Lua 5.1 alpha came out today. +
+ +LuaJIT 1.0.1 — 2005-08-31
+-
+
- Missing GC step in OP_CONCAT. +
- Fix result handling for C –> JIT calls. +
- Detect CPU feature bits. +
- Encode conditional moves (fucomip) only when supported. +
- Add fallback instructions for FP compares. +
- Add support for LUA_COMPAT_VARARG. Still disabled by default. +
- MSVC needs a specific place for the CALLBACK attribute +(David Burgess). +
- Misc. doc updates. +
+Interim non-public release. +Special thanks to Adam D. Moss for reporting most of the bugs. +
+ +LuaJIT 1.0.0 — 2005-08-29
++This is the initial non-public release of LuaJIT. +
++