| Age | Commit message (Expand) | Author |
|---|
| 2017-03-27 | preserve side effects in switch expression (#1694)...fixes #1690 | Alex Lam S.L |
| 2017-03-27 | fix `cascade` on anonymous function reference (#1693)...Unlike normal variables and even function definitions, these cannot be reassigned, even though assignment expressions would "leak" the assigned value as normal. | Alex Lam S.L |
| 2017-03-27 | 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. | Alex Lam S.L |
| 2017-03-26 | fix `delete` related issues in `collapse_vars` and `reduce_vars` (#1689) | Alex Lam S.L |
| 2017-03-26 | fix `cascade` on `delete` operator (#1687)...Conditions including strict mode would make `delete` return `true` or `false`, and are too complex to be evaluated by the compressor.
Suppress assignment folding into said operator.
fixes #1685 | Alex Lam S.L |
| 2017-03-26 | fallthrough should not execute case expression (#1683)...- de-duplicate trailing cases only, avoid all potential side-effects
- enable switch statement fuzzing
fixes #1680 | Alex Lam S.L |
| 2017-03-26 | optimize conditional when condition symbol matches consequent (#1684) | kzc |
| 2017-03-26 | suppress switch branch de-duplication upon side effects (#1682)...fixes #1679 | Alex Lam S.L |
| 2017-03-26 | fix side-effects detection on switch statements (#1678)...extension of #1675 | Alex Lam S.L |
| 2017-03-26 | improve switch optimisations (#1677)...- correctly determine reachability of (default) branches
- gracefully handle multiple default branches
- optimise branches with duplicate bodies
fixes #376
fixes #441
fixes #1674 | Alex Lam S.L |
| 2017-03-25 | fix `has_side_effects()` (#1675)...`AST_Try` is an `AST_Block`, so besides try block we also need to inspect catch and finally blocks for possible side effects.
Also extend this functionality to handle `AST_If` and `AST_LabeledStatement` while we are at it.
fixes #1673 | Alex Lam S.L |
| 2017-03-25 | fix `reduce_vars` on `AST_Switch` (#1671)...Take conditional nature of switch branches into account.
fixes #1670 | Alex Lam S.L |
| 2017-03-25 | fix typeof side-effects (#1669)...`has_side_effects()` does not take `typeof`'s magical power of not tripping over undeclared variable into account.
fixes #1668 | Alex Lam S.L |
| 2017-03-25 | fix `dead_code` on `AST_Switch` (#1667)...Need to call `extract_declarations_from_unreachable_code()`.
fixes #1663 | Alex Lam S.L |
| 2017-03-25 | fix invalid `AST_For.init` (#1657)...Turns out the only place in `Compressor` which can generate invalid `AST_For.init` is within `drop_unused()`, so focus the fix-up efforts.
supercedes #1652
fixes #1656 | Alex Lam S.L |
| 2017-03-24 | fix cascade of `evaluate` optimisation (#1654)...Operator has changed, so break out from rest of the rules.
fixes #1649 | Alex Lam S.L |
| 2017-03-24 | fix corner case in `AST_For.init` (#1652)...Enforce `null` as value for empty initialisation blocks.
fixes #1648 | Alex Lam S.L |
| 2017-03-24 | fix assignment extraction from conditional (#1651)...fixes #1645
fixes #1646 | Alex Lam S.L |
| 2017-03-24 | fix assignment substitution in sequences (#1643)...take side effects of binary boolean operations into account
fixes #1639 | Alex Lam S.L |
| 2017-03-24 | improve collapsible value detection (#1638)...- #1634 bars variables with cross-scope references in between to collapse
- but if assigned value is side-effect-free, no states can be modified, so it is safe to move | Alex Lam S.L |
| 2017-03-23 | account for cross-scope modifications in `collapse_vars` (#1634)...mostly done by @kzc
fixes #1631 | Alex Lam S.L |
| 2017-03-23 | introduce compressor.info() (#1633)...report the following only when `options.warnings = "verbose"`
- unused elements due to inlining
- collpased variables | Alex Lam S.L |
| 2017-03-19 | fix commit 88fb83a (#1622)...The following is wrong:
`a == (b ? a : c)` => `b`
Because:
- `b` may not be boolean
- `a` might have side effects
- `a == a` is not always `true` (think `NaN`)
- `a == c` is not always `false` | Alex Lam S.L |
| 2017-03-19 | fix AST_Binary.lift_sequences() (#1621)...Commit eab99a1c fails to account for side effects from compound assignments. | Alex Lam S.L |
| 2017-03-19 | transform String.charAt() to index access (#1620)...Guarded by `unsafe` as `charAt()` can be overridden. | Alex Lam S.L |
| 2017-03-17 | fix chained evaluation (#1610)...`reduce_vars` enables substitution of variables but did not clone the value's `AST_Node`.
This confuses `collapse_vars` and result in invalid AST and subsequent crash.
fixes #1609 | Alex Lam S.L |
| 2017-03-16 | make `collapse_vars` consistent with `toplevel` (#1608)...fixes #1605 | Alex Lam S.L |
| 2017-03-16 | fix `hoist_vars` on `reduce_vars` (#1607)...`hoist_vars` converts variable declarations into plain assignments, which then confuses `reduce_vars`
fixes #1606 | Alex Lam S.L |
| 2017-03-16 | fix stack issues with `AST_Node.evaluate()` (#1603)...As patched in #1597, `make_node_from_constant()` makes inconsistent and sometimes incorrect calls to `optimize()` and `transform()`.
Fix those issues properly by changing the semantics of `evaluate()` and `make_node_from_constant()`, with the side effect that `evaluate()` no longer eagerly converts constant to `AST_Node`. | Alex Lam S.L |
| 2017-03-15 | fix `AST_Node.optimize()` (#1602)...Liberal use of `Compressor.transform()` and `AST_Node.optimize()` presents an issue for look-up operations like `TreeWalker.in_boolean_context()` and `TreeWalker.parent()`.
This is an incremental fix such that `AST_Node.optimize()` would now contain the correct stack information when called correctly. | Alex Lam S.L |
| 2017-03-14 | minor clean-ups (#1600)...- remove obsolete optimisation in `AST_Binary` after #1477
- improve `TreeWalker.has_directive()` readability and resilience against multiple visits | Alex Lam S.L |
| 2017-03-11 | temporary fix for boolean bug (#1597)...fixes #1592 | Alex Lam S.L |
| 2017-03-11 | 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 | Alex Lam S.L |
| 2017-03-09 | 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 | Alex Lam S.L |
| 2017-03-09 | scan RHS of dropped assignments (#1581)...- similar case as #1578 but against #1450 instead
- fix `this` binding in #1450 as well
closes #1580 | Alex Lam S.L |
| 2017-03-08 | scan assignment value in drop_unused() (#1578)...those were not optimised for `unused` before, which made it necessary for `reduce_vars` to have separate steps for `keep_fnames`
docs update by @kzc
closes #1577 | Alex Lam S.L |
| 2017-03-08 | 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 | Alex Lam S.L |
| 2017-03-08 | fix return from recursive IIFE (#1570)...`side-effects` did not account for IIFEs being able to reference itself thus making its return value potentially significant | Alex Lam S.L |
| 2017-03-07 | transform function calls to IIFEs (#1560)...- expose function body to call sites for potential optimisations
- suppress substitution of variable used within `AST_Defun` | Alex Lam S.L |
| 2017-03-07 | avoid substitution of global variables (#1557)...- unless `toplevel` is enabled
- global `const` works as before | Alex Lam S.L |
| 2017-03-07 | collapse_vars: do not replace a constant in loop condition or init (#1562) | kzc |
| 2017-03-05 | fixup for #1553 (#1555)...- `++a` is the one that is foldable
- transform `a++` into `++a` for better optimisation | Alex Lam S.L |
| 2017-03-05 | collapse assignment with adjacent subsequent usage (#1553)...- consolidate `cascade` optimisations
- support ++/-- postfixes
- remove redundant optimisation identified in #1460
fixes #368 | Alex Lam S.L |
| 2017-03-05 | handle variable declaration within catch blocks (#1546)...accounts for IE8- scoping | Alex Lam S.L |
| 2017-03-05 | improve `unsafe` on undefined (#1548)...`unsafe` turns undefined keyword into a variable of the same name if found, but that interferes with other related optimisations.
Keep track of such transformations to ensure zero information loss in the process. | Alex Lam S.L |
| 2017-03-05 | stay safe with constants in IE8- (#1547)...- `undefined` etc. can be redefined at top-level for IE8-, so disable related optimisations
- fixed `--support-ie8` catch mangle bug | Alex Lam S.L |
| 2017-03-05 | fix a corner case in #1530 (#1552) | Alex Lam S.L |
| 2017-03-04 | disallow collapse_vars constant replacement in for-in statements (#1543) | kzc |
| 2017-03-03 | process code with implicit return statement (#1522)...Bookmarklet for instance implicitedly assumes a "completion value" without using `return`.
The `expression` option now supports such use cases.
Optimisations on IIFEs also enhanced.
fixes #354
fixes #543
fixes #625
fixes #628
fixes #640
closes #1293 | Alex Lam S.L |
| 2017-03-03 | compress numerical expressions (#1513)...safe operations
- `a === b` => `a == b`
- `a + -b` => `a - b`
- `-a + b` => `b - a`
- `a+ +b` => `+b+a`
associative operations
(bit-wise operations are safe, otherwise `unsafe_math`)
- `a + (b + c)` => `(a + b) + c`
- `(n + 2) + 3` => `5 + n`
- `(2 * n) * 3` => `6 * n`
- `(a | 1) | (2 | d)` => `(3 | a) | b`
fixes #412 | Alex Lam S.L |
