Commit Graph

28 Commits

Author SHA1 Message Date
alexlamsl
21e82f4ea5 compress duplicated variable definitions
These are surprisingly common, as people reuse the same variable name within loops or switch branches.
2017-04-17 14:06:38 +08:00
Alex Lam S.L
71a8d0d236 fix reduce_vars within try-block (#1818)
Possible partial execution due to exceptions.
2017-04-17 14:03:29 +08:00
Alex Lam S.L
1a498db2d3 enhance reduce_vars (#1814)
- allow immediate assignment after declaration of variable
- relax modification rule for immutable value
- fix order of visit for TreeWalker
- remove extraneous code
2017-04-17 01:36:50 +08:00
Alex Lam S.L
44dfa5a318 fix variable substitution (#1816)
- let `collapse_vars` take care of value containing any symbols
- improve overhead accounting
2017-04-16 17:25:39 +08:00
Alex Lam S.L
0f4cd73dcc introduce "strict" to pure_getters (#1795) 2017-04-07 13:31:58 +08:00
Alex Lam S.L
281e882d27 fix reduce_vars on catch variable (#1794)
Improved catch handling in `figure_out_scope()` means special case treatment of IE8 is no longer valid in `reset_opt_flags()`.

Also fixed recursive assignment in variable definition.
2017-04-07 12:32:56 +08:00
Alex Lam S.L
cc6aa3e5ac fix incorrect context in variable substitution (#1791)
`AST_Node.optimize()` is context-aware, so don't cache its results to be used elsewhere.

Also fixed a few cases of AST corruption and beef up safety of `pure_getters`.
2017-04-07 03:42:17 +08:00
Alex Lam S.L
f7ca4f2297 fix corner cases in switch and undefined (#1762)
- fix side effects in switch condition for singular blocks
- fix `undefined` confusion with local variable
- gate `OPT(AST_Switch)` with `switches`

fixes #1758
fixes #1759
2017-04-02 14:52:25 +08:00
Alex Lam S.L
57ce5bd9e0 handle overlapped variable definitions (#1691)
Process variable definitions with or without assigned values against:
- `arguments`
- named function arguments
- multiple definitions within same scope

Essentially demote variable declarations with no value assignments.

Also fixed invalid use of `AST_VarDef` over `arguments` - should use a member of `AST_SymbolDeclaration` instead.
2017-03-27 01:30:21 +08:00
Alex Lam S.L
861a79ac9f fix delete related issues in collapse_vars and reduce_vars (#1689) 2017-03-26 19:14:30 +08:00
Alex Lam S.L
0a65de89b9 fix reduce_vars on AST_Switch (#1671)
Take conditional nature of switch branches into account.

fixes #1670
2017-03-25 21:17:30 +08:00
Alex Lam S.L
a3cc3a9b87 make expect_stdout work on Node.js 0.12 (#1623)
That particular version of Node.js has messed up error messages, so provide a version-specific workaround.

Also fixed an formatting issue which would cause `expect_stdout` to fail if error message contains excerpts of input.

Apply `expect_stdout` to more applicable tests.
2017-03-19 12:00:32 +08:00
Alex Lam S.L
a80b228d8b fix hoist_vars on reduce_vars (#1607)
`hoist_vars` converts variable declarations into plain assignments, which then confuses `reduce_vars`

fixes #1606
2017-03-16 12:03:30 +08:00
Alex Lam S.L
d9344f30b8 disallow parameter substitution for named IIFEs (#1596)
Self-referenced function has non-fixed values assigned to its parameters.

Let `unused` & `!keep_fnames` do the scanning, then apply `reduce_vars` only to unnamed functions.

fixes #1595
2017-03-11 03:34:55 +08:00
Alex Lam S.L
b633706ce4 fix & improve function argument compression (#1584)
- one-use function call => IIFE should take `eval()` & `arguments` into account
- if unused parameter cannot be eliminated, replace it with `0`

fixes #1583
2017-03-09 19:11:05 +08:00
Alex Lam S.L
c7cdcf06a6 fix function name eliminiation (#1576)
Function expression can be assigned to a variable and be given a name. Ensure function name is the reduced variable before clearing it out.

fixes #1573
fixes #1575
2017-03-08 12:39:57 +08:00
Alex Lam S.L
8a8a94a596 fix deep cloning of labels (#1565)
`AST_Label.references` get `.initialize()` to `[]` every time after `.clone()`

So walk down the tree to pick up the cloned `AST_LoopControl` pieces and put it back together.
2017-03-07 18:38:27 +08:00
Alex Lam S.L
8153b7bd8a transform function calls to IIFEs (#1560)
- expose function body to call sites for potential optimisations
- suppress substitution of variable used within `AST_Defun`
2017-03-07 15:37:52 +08:00
Alex Lam S.L
d787d70127 avoid substitution of global variables (#1557)
- unless `toplevel` is enabled
- global `const` works as before
2017-03-07 03:11:03 +08:00
Alex Lam S.L
b70591be1a handle variable declaration within catch blocks (#1546)
accounts for IE8- scoping
2017-03-05 13:13:44 +08:00
Alex Lam S.L
70d72ad806 properly cover all cases of for-in loop variables (#1536) 2017-03-03 02:39:57 +08:00
Alex Lam S.L
fe9227a41b fix reference marking in for-in loops (#1535)
fixes #1533
2017-03-03 00:56:06 +08:00
Alex Lam S.L
7aa69117e1 fix corner cases in reduce_vars (#1524)
Avoid variable substitution in the following cases:
- use of variable before declaration
- declaration within conditional code blocks
- declaration within loop body

fixes #1518
fixes #1525
2017-03-02 00:20:53 +08:00
Alex Lam S.L
16cd5d57a5 consolidate evaluate & reduce_vars (#1505)
- improve marking efficiency
- apply smarter `const` replacement to `var`

fixes #1501
2017-02-26 00:40:33 +08:00
alexlamsl
a0f4fd390a improve reduce_vars and fix a bug
- update modified flag between compress() passes
- support IIFE arguments
- fix corner case with multiple definitions

closes #1473
2017-02-21 13:29:58 +08:00
Alex Lam S.L
0610c020b1 optimise binary operands with evaluate() (#1427)
- remove call to evaluate() in is_constant() and let nested optimize() does its job instead
- reject RegExp in is_constant() and remove special case logic under collapse_vars
- operands to conditionals optimisation are now always evaluate()-ed
- throw error in constant_value() instead of returning undefined to catch possible bugs, similar to make_node_from_constant()
- optimise binary boolean operators under `evaluate` instead of `conditionals`
2017-01-26 12:16:50 +01:00
Alex Lam S.L
0d7d4918eb augment evaluate to extract within objects (#1425)
- gated by `unsafe`
- replaces previous optimisation specific to String.length
- "123"[0] => 1
- [1, 2, 3][0] => 1
- [1, 2, 3].length => 3
- does not apply to objects with overridden prototype functions
2017-01-26 12:14:18 +01:00
alexlamsl
4761d07e0b Optimize unmodified variables 2016-10-01 11:36:11 +02:00