lua/ltable.h, branch v5.5.1A mirror of https://github.com/lua/lua
https://git.lua4.win/lua/atom?h=v5.5.12025-07-18T19:18:30+00:00Randomness added to table length computation2025-07-18T19:18:30+00:00Roberto Ierusalimschyroberto@inf.puc-rio.br2025-07-18T19:18:30+00:00urn:sha1:303f4155593721dfd57dadc6e56122e465ce9efb
A bad actor could fill only a few entries in a table (power of twos in
decreasing order, see tests) and produce a small table with a huge
length. If your program builds a table with external data and iterates
over its length, this behavior could be an issue.
Scanner and parser use different tables for constants2024-12-17T14:23:22+00:00Roberto Ierusalimschyroberto@inf.puc-rio.br2024-12-17T14:23:22+00:00urn:sha1:1c40ff9faafed620aa0458b397bcbfbe19e0f663
Moreover, each function being parsed has its own table.
The code is cleaner when each table is used for one specific purpose:
The scanner uses its table to anchor and unify strings, mapping strings
to themselves; the parser uses it to reuse constants in the code,
mapping constants to their indices in the constant table. A different
table for each task avoids false collisions.
'luaH_fastseti' uses 'checknoTM'2024-12-11T18:32:43+00:00Roberto Ierusalimschyroberto@inf.puc-rio.br2024-12-11T18:32:43+00:00urn:sha1:412e9a4d952d47631feddfa4ec25a520ec75b103
The extra check in checknoTM (versus only checking whether there is a
metatable) is cheap, and it is not that uncommon for a table to have a
metatable without a __newindex metafield.
New way to keep hints for table length2024-11-29T20:26:20+00:00Roberto Ierusalimschyroberto@inf.puc-rio.br2024-11-29T20:26:20+00:00urn:sha1:002beeebe79065e03dd9f531bee367e8459e3f64
Instead of using 'alimit' for keeping the size of the array and at
the same time being a hint for '#t', a table now keeps these two
values separate. The Table structure has a field 'asize' with the
size of the array, while the length hint is kept in the array itself.
That way, tables with no array part waste no space with that field.
Moreover, the space for the hint may have zero cost for small arrays,
if the array of tags plus the hint still fits in a single word.
'objsize' returns 'l_mem'2024-11-15T15:04:53+00:00Roberto Ierusalimschyroberto@inf.puc-rio.br2024-11-15T15:04:53+00:00urn:sha1:a4762b6ffe74f5878882ef238d37bfa92d90e418
Sums of size_t may not fit in a size_t.
'objsize' broke in smaller pieces2024-09-30T17:01:42+00:00Roberto Ierusalimschyroberto@inf.puc-rio.br2024-09-30T17:01:42+00:00urn:sha1:3d54b42d59bcc1b31a369f3497ac22745d63cae6Added gcc option '-Wconversion'2024-07-27T16:32:59+00:00Roberto Ierusalimschyroberto@inf.puc-rio.br2024-07-27T16:32:59+00:00urn:sha1:0acd55898d0aaae8dbc14c8a1bc1e3bdffc8701b
No warnings for standard numerical types. Still pending alternative
numerical types.
Encoding of table indices (hres) must use C indices2024-06-10T15:09:35+00:00Roberto Ierusalimschyroberto@inf.puc-rio.br2024-06-10T15:09:35+00:00urn:sha1:94b503d95ef00f1e38b58b024ef45bf8973a8746
As the encoding of array indices is (~index), 0 is encoded as -1 and
INT_MAX is encoded as INT_MIN.
Yet another representation for arrays2024-04-05T18:35:11+00:00Roberto Ierusalimschyroberto@inf.puc-rio.br2024-04-05T18:35:11+00:00urn:sha1:5edacafcfa36a1fa86a7b5316bacf8c6a2c47227
This "linear" representation (see ltable.h for details) has worse
locality than cells, but the simpler access code seems to compensate
that.
Some 'unsigned int' changed to 'unsigned'2024-03-22T17:06:11+00:00Roberto Ierusalimschyroberto@inf.puc-rio.br2024-03-22T17:06:11+00:00urn:sha1:9fa63a62682c1353eeabd4575152941fa6f3e70f
'unsigned int' is too long sometimes. (We already write 'long' instead
of 'long int'...)