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* Refactor interaction between Pass and PassRunner (#5093)Thomas Lively2022-09-301-1/+3
| | | | | | | | | | | | | | Previously only WalkerPasses had access to the `getPassRunner` and `getPassOptions` methods. Move those methods to `Pass` so all passes can use them. As a result, the `PassRunner` passed to `Pass::run` and `Pass::runOnFunction` is no longer necessary, so remove it. Also update `Pass::create` to return a unique_ptr, which is more efficient than having it return a raw pointer only to have the `PassRunner` wrap that raw pointer in a `unique_ptr`. Delete the unused template `PassRunner::getLast()`, which looks like it was intended to enable retrieving previous analyses and has been in the code base since 2015 but is not implemented anywhere.
* [Wasm GC] Support non-nullable locals in the "1a" form (#4959)Alon Zakai2022-08-311-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | An overview of this is in the README in the diff here (conveniently, it is near the top of the diff). Basically, we fix up nn locals after each pass, by default. This keeps things easy to reason about - what validates is what is valid wasm - but there are some minor nuances as mentioned there, in particular, we ignore nameless blocks (which are commonly added by various passes; ignoring them means we can keep more locals non-nullable). The key addition here is LocalStructuralDominance which checks which local indexes have the "structural dominance" property of 1a, that is, that each get has a set in its block or an outer block that precedes it. I optimized that function quite a lot to reduce the overhead of running that logic after each pass. The overhead is something like 2% on J2Wasm and 0% on Dart (0%, because in this mode we shrink code size, so there is less work actually, and it balances out). Since we run fixups after each pass, this PR removes logic to manually call the fixup code from various places we used to call it (like eh-utils and various passes). Various passes are now marked as requiresNonNullableLocalFixups => false. That lets us skip running the fixups after them, which we normally do automatically. This helps avoid overhead. Most passes still need the fixups, though - any pass that adds a local, or a named block, or moves code around, likely does. This removes a hack in SimplifyLocals that is no longer needed. Before we worked to avoid moving a set into a try, as it might not validate. Now, we just do it and let fixups happen automatically if they need to: in the common code they probably don't, so the extra complexity seems not worth it. Also removes a hack from StackIR. That hack tried to avoid roundtrip adding a nondefaultable local. But we have the logic to fix that up now, and opts will likely keep it non-nullable as well. Various tests end up updated here because now a local can be non-nullable - previous fixups are no longer needed. Note that this doesn't remove the gc-nn-locals feature. That has been useful for testing, and may still be useful in the future - it basically just allows nn locals in all positions (that can't read the null default value at the entry). We can consider removing it separately. Fixes #4824
* [Wasm Exceptions] Handle delegation to the caller in RemoveUnusedNames (#3585)Alon Zakai2021-02-181-1/+6
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* [Wasm Exceptions] Fix RemoveUnusedNames on Try (#3583)Alon Zakai2021-02-181-11/+11
| | | | | | | | | | | | | | The delegate field of Try was not being scanned, so we could remove a name that was used only by a delegate. The bug was because visitTry overrides the generic visitor visitExpression. So we need to call it manually. Sadly the code here was pretty old (I probably wrote it back in 2015 or so) and it was misleading, as it had unnecessary calls from the generic visitor to visitBlock, visitLoop, which are not needed. This PR removes them which is shorter and cleaner. Also, we must handle the case of the delegate field being unset, so check name.is().
* [EH] Support reading/writing of delegate (#3561)Heejin Ahn2021-02-121-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds support for reading/writing of the new `delegate` instruction in the folded wast format, the stack IR format, the poppy IR format, and the binary format in Binaryen. We don't have a formal spec written down yet, but please refer to WebAssembly/exception-handling#137 and WebAssembly/exception-handling#146 for the informal semantics. In the current version of spec `delegate` is basically a rethrow, but with branch-like immediate argument so that it can bypass other catches/delegates in between. `delegate` is not represented as a new `Expression`, but it is rather an option within a `Try` class, like `catch`/`catch_all`. One special thing about `delegate` is, even though it is written _within_ a `try` in the folded wat format, like ```wasm (try (do ... ) (delegate $l) ) ``` In the unfolded wat format or in the binary format, `delegate` serves as a scope end instruction so there is no separate `end`: ```wasm try ... delegate $l ``` `delegate` semantically targets an outer `catch` or `delegate`, but we write `delegate` target as a `try` label because we only give labels to block-like scoping expressions. So far we have not given `Try` a label and used inner blocks or a wrapping block in case a branch targets the `try`. But in case of `delegate`, it can syntactically only target `try` and if it targets blocks or loops it is a validation failure. So after discussions in #3497, we give `Try` a label but this label can only be targeted by `delegate`s. Unfortunately this makes parsing and writing of `Try` expression somewhat complicated. Also there is one special case; if the immediate argument of `try` is the same as the depth of control flow stack, this means the 'delegate' delegates to the caller. To handle this case this adds a fake label `DELEGATE_CALLER_TARGET`, and when writing it back to the wast format writes it as an immediate value, unlike other cases in which we write labels. This uses `DELEGATE_FIELD_SCOPE_NAME_DEF/USE` to represent `try`'s label and `delegate`'s target. There are many cases that `try` and `delegate`'s labels need to be treated in the same way as block and branch labels, such as for hashing or comparing. But there are routines in which we automatically assume all label uses are branches. I thought about adding a new kind of defines such as `DELEGATE_FIELD_TRY_NAME_DEF/USE`, but I think it will also involve some duplication of existing routines or classes. So at the moment this PR chooses to use the existing `DELEGATE_FIELD_SCOPE_NAME_DEF/USE` for `try` and `delegate` labels and makes only necessary amount of changes in branch-utils. We can revisit this decision later if necessary. Many of changes to the existing test cases are because now all `try`s are automatically assigned a label. They will be removed in `RemoveUnusedNames` pass in the same way as block labels if not targeted by any delegates. This only supports reading and writing and has not been tested against any optimization passes yet. --- Original unfolded wat file to generate test/try-delegate.wasm: ```wasm (module (event $e) (func try try delegate 0 catch $e end) (func try try catch $e i32.const 0 drop try delegate 1 end catch $e end ) ) ```
* Refactor BranchUtils to avoid boilerplate. NFC (#3442)Alon Zakai2020-12-141-29/+15
| | | This should make it easier to add br_on_cast for example.
* Fix RemoveUnusedNames on a loop with no name and a child with a different ↵Alon Zakai2020-04-241-1/+1
| | | | type. fixes #2807 (#2808)
* Add string parameter to WASM_UNREACHABLE (#2499)Sam Clegg2019-12-051-1/+1
| | | | | This works more like llvm's unreachable handler in that is preserves information even in release builds.
* Add basic exception handling support (#2282)Heejin Ahn2019-08-131-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds basic support for exception handling instructions, according to the spec: https://github.com/WebAssembly/exception-handling/blob/master/proposals/Exceptions.md This PR includes support for: - Binary reading/writing - Wast reading/writing - Stack IR - Validation - binaryen.js + C API - Few IR routines: branch-utils, type-updating, etc - Few passes: just enough to make `wasm-opt -O` pass - Tests This PR does not include support for many optimization passes, fuzzer, or interpreter. They will be follow-up PRs. Try-catch construct is modeled in Binaryen IR in a similar manner to that of if-else: each of try body and catch body will contain a block, which can be omitted if there is only a single instruction. This block will not be emitted in wast or binary, as in if-else. As in if-else, `class Try` contains two expressions each for try body and catch body, and `catch` is not modeled as an instruction. `exnref` value pushed by `catch` is get by `pop` instruction. `br_on_exn` is special: it returns different types of values when taken and not taken. We make `exnref`, the type `br_on_exn` pushes if not taken, as `br_on_exn`'s type.
* clang-tidy braces changes (#2075)Alon Zakai2019-05-011-3/+6
| | | Applies the changes in #2065, and temprarily disables the hook since it's too slow to run on a change this large. We should re-enable it in a later commit.
* Apply format changes from #2048 (#2059)Alon Zakai2019-04-261-17/+15
| | | Mass change to apply clang-format to everything. We are applying this in a PR by me so the (git) blame is all mine ;) but @aheejin did all the work to get clang-format set up and all the manual work to tidy up some things to make the output nicer in #2048
* merge blocks in remove-unused-names only when their type is identical, so ↵Alon Zakai (kripken)2017-08-051-1/+1
| | | | branches to them are interchangeable
* Validate finalization (#1014)Alon Zakai2017-05-181-0/+1
| | | | | | | * validate that types are properly finalized, when in pass-debug mode (BINARYEN_PASS_DEBUG env var): check after each pass is run that the type of each node is equal to the proper type (when finalizing it, i.e., fully recomputing the type). * fix many fuzz bugs found by that. * in particular, fix dce bugs with type changes not being fully updated during code removal. add a new TypeUpdater helper class that lets a pass update types efficiently, by the helper tracking deps between blocks and branches etc., and updating/propagating type changes only as necessary.
* Default Walker subclasses to using Visitor<SubType> (#921)jgravelle-google2017-02-231-1/+1
| | | | Most module walkers use PostWalker<T, Visitor<T>>, let that pattern be expressed as simply PostWalker<T>
* loops no longer have an out label and other upstream loop updatesAlon Zakai2016-09-071-25/+3
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* more RemoveUnusedName opts: merge names when possible, and do block/loop ↵Alon Zakai2016-07-201-5/+42
| | | | merging based on their names
* remove unused labels from loops too, and general clean ups for RemoveUnusedNamesAlon Zakai2016-07-201-7/+28
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* Add initialization functions for passes to avoid missing pass registration ↵Jukka Jylänki2016-06-211-1/+3
| | | | due to linker dead code elimination. Fixes #577.
* move function parallelism to pass and pass runner, which allows more ↵Alon Zakai2016-06-031-1/+3
| | | | efficient parallel execution (#564)
* create a UnifiedExpressionVisitor for passes that want a single visitor ↵Alon Zakai2016-04-181-1/+1
| | | | function, to avoid confusion with having both visit* and visitExpression in a single pass (#357)
* Function parallelism (#343)Alon Zakai2016-04-151-0/+2
| | | | * allow traversals to mark themselves as function-parallel, in which case we run them using a thread pool. also mark some thread-safety risks (interned strings, arena allocators) with assertions they modify only on the main thread
* De-recurse traversals (#333)Alon Zakai2016-04-111-1/+1
| | | | | | | | | | | | * refactor core walking to not recurse * add a simplify-locals test * reuse parent's non-branchey scan logic in SimpleExecutionWalker, reduce code duplication * update wasm.js * rename things following comments
* br_table, no more casesAlon Zakai2016-03-071-0/+7
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* Some cleanup.Michael Bebenita2016-01-141-1/+1
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* Use LLVM style static polymorphism for WasmVisitors.Michael Bebenita2016-01-131-4/+4
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* A more generic compiler pass system.Michael Bebenita2016-01-131-1/+1
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* fix RemoveUnusedNamesAlon Zakai2016-01-051-13/+11
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* add RemoveUnusedNames passAlon Zakai2016-01-041-0/+50