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* Refactor interaction between Pass and PassRunner (#5093)Thomas Lively2022-09-301-2/+6
| | | | | | | | | | | | | | 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 Zakai2022-08-311-35/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Remove RTTs (#4848)Thomas Lively2022-08-051-4/+6
| | | | | | | RTTs were removed from the GC spec and if they are added back in in the future, they will be heap types rather than value types as in our implementation. Updating our implementation to have RTTs be heap types would have been more work than deleting them for questionable benefit since we don't know how long it will be before they are specced again.
* [Wasm GC] Avoid dangerous StackIR opts on GC (#4007)Alon Zakai2021-07-221-4/+40
| | | | | | | | removeUnneededBlocks() can force us to use a local when we load the emitted wasm, which can't work for something nondefaultable like an RTT. For now, just don't run that optimization if GC is enabled. Eventually, perhaps we'll want to enable this optimization in a different way.
* Allow only computing necessary influences in LocalGraph. NFC (#3861)Alon Zakai2021-05-051-1/+1
| | | | | | | Some passes need setInfluences but not getInfluences, but were computing them nonetheless. This makes e.g. MergeLocals 12% faster. It will also help use LocalGraph in new passes with less worries about speed.
* [EH] Support reading/writing of delegate (#3561)Heejin Ahn2021-02-121-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ) ) ```
* Support Stack IR for new try-catch(_all) (#3538)Heejin Ahn2021-02-031-0/+1
| | | | | This adds missing stack IR printing support for the new form of try-catch-catch_all. Also uses `printMedium` when printing instructions consistently.
* Initial implementation of "Memory64" proposal (#3130)Wouter van Oortmerssen2020-09-181-1/+1
| | | Also includes a lot of new spec tests that eventually need to go into the spec repo
* [NFC] Enforce use of `Type::` on type names (#2434)Thomas Lively2020-01-071-2/+2
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* Remove 'none' type as a branch target in ReFinalize (#2492)Alon Zakai2019-12-041-1/+1
| | | | | | | | | | | | | | | | | That was needed for super-old wasm type system, where we allowed (block $x (br_if $x (unreachable) (nop) ) ) That is, we differentiated "taken" branches from "named" ones (just referred to by name, but not actually taken as it's in unreachable code). We don't need to differentiate those any more. Remove the ReFinalize code that considered it, and also remove the named/taken distinction in other places.
* Multivalue type creation and inspection (#2459)Thomas Lively2019-11-221-1/+1
| | | | | | | | | | | | | Adds the ability to create multivalue types from vectors of concrete value types. All types are transparently interned, so their representation is still a single uint32_t. Types can be extracted into vectors of their component parts, and all the single value types expand into vectors containing themselves. Multivalue types are not yet used in the IR, but their creation and inspection functionality is exposed and tested in the C and JS APIs. Also makes common type predicates methods of Type and improves the ergonomics of type printing.
* Add Stack IR optimization support for EH (#2425)Heejin Ahn2019-11-071-3/+7
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* Refactor stack IR / binary writer (NFC) (#2250)Heejin Ahn2019-07-231-20/+3
| | | | | | | | | | | | | | | | Previously `StackWriter` and its subclasses had routines for all three modes (`Binaryen2Binary`, `Binaryen2Stack`, and `Stack2Binary`) within a single class. This splits routines for each in a separate class and also factors out binary writing into a separate class (`BinaryInstWriter`) so other classes can make use of it. The new classes are: - `BinaryInstWriter`: Binary instruction writer. Only responsible for emitting binary contents and no other logic - `BinaryenIRWriter`: Converts binaryen IR into something else - `BinaryenIRToBinaryWriter`: Writes binaryen IR to binary - `StackIRGenerator`: Converts binaryen IR to stack IR - `StackIRToBinaryWriter`: Writes stack IR to binary
* Reflect instruction renaming in code (#2128)Heejin Ahn2019-05-211-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | - Reflected new renamed instruction names in code and tests: - `get_local` -> `local.get` - `set_local` -> `local.set` - `tee_local` -> `local.tee` - `get_global` -> `global.get` - `set_global` -> `global.set` - `current_memory` -> `memory.size` - `grow_memory` -> `memory.grow` - Removed APIs related to old instruction names in Binaryen.js and added APIs with new names if they are missing. - Renamed `typedef SortedVector LocalSet` to `SetsOfLocals` to prevent name clashes. - Resolved several TODO renaming items in wasm-binary.h: - `TableSwitch` -> `BrTable` - `I32ConvertI64` -> `I32WrapI64` - `I64STruncI32` -> `I64SExtendI32` - `I64UTruncI32` -> `I64UExtendI32` - `F32ConvertF64` -> `F32DemoteI64` - `F64ConvertF32` -> `F64PromoteF32` - Renamed `BinaryenGetFeatures` and `BinaryenSetFeatures` to `BinaryenModuleGetFeatures` and `BinaryenModuleSetFeatures` for consistency.
* clang-tidy braces changes (#2075)Alon Zakai2019-05-011-5/+10
| | | 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 Zakai2019-04-261-44/+31
| | | 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
* Massive renaming (#1855)Thomas Lively2019-01-071-3/+3
| | | | | | Automated renaming according to https://github.com/WebAssembly/spec/issues/884#issuecomment-426433329.
* Print Stack IR in proper .wat format (#1630)Alon Zakai2018-08-141-26/+0
| | | This now makes --generate-stack-ir --print-stack-ir emit a fully valid .wat wasm file, in stacky format.
* Stack IR (#1623)Alon Zakai2018-07-301-0/+393
This adds a new IR, "Stack IR". This represents wasm at a very low level, as a simple stream of instructions, basically the same as wasm's binary format. This is unlike Binaryen IR which is structured and in a tree format. This gives some small wins on binary sizes, less than 1% in most cases, usually 0.25-0.50% or so. That's not much by itself, but looking forward this prepares us for multi-value, which we really need an IR like this to be able to optimize well. Also, it's possible there is more we can do already - currently there are just a few stack IR optimizations implemented, DCE local2stack - check if a set_local/get_local pair can be removed, which keeps the set's value on the stack, which if the stars align it can be popped instead of the get. Block removal - remove any blocks with no branches, as they are valid in wasm binary format. Implementation-wise, the IR is defined in wasm-stack.h. A new StackInst is defined, representing a single instruction. Most are simple reflections of Binaryen IR (an add, a load, etc.), and just pointers to them. Control flow constructs are expanded into multiple instructions, like a block turns into a block begin and end, and we may also emit extra unreachables to handle the fact Binaryen IR has unreachable blocks/ifs/loops but wasm does not. Overall, all the Binaryen IR differences with wasm vanish on the way to stack IR. Where this IR lives: Each Function now has a unique_ptr to stack IR, that is, a function may have stack IR alongside the main IR. If the stack IR is present, we write it out during binary writing; if not, we do the same binaryen IR => wasm binary process as before (this PR should not affect speed there). This design lets us use normal Passes on stack IR, in particular this PR defines 3 passes: Generate stack IR Optimize stack IR (might be worth splitting out into separate passes eventually) Print stack IR for debugging purposes Having these as normal passes is convenient as then they can run in parallel across functions and all the other conveniences of our current Pass system. However, a downside of keeping the second IR as an option on Functions, and using normal Passes to operate on it, means that we may get out of sync: if you generate stack IR, then modify binaryen IR, then the stack IR may no longer be valid (for example, maybe you removed locals or modified instructions in place etc.). To avoid that, Passes now define if they modify Binaryen IR or not; if they do, we throw away the stack IR. Miscellaneous notes: Just writing Stack IR, then writing to binary - no optimizations - is 20% slower than going directly to binary, which is one reason why we still support direct writing. This does lead to some "fun" C++ template code to make that convenient: there is a single StackWriter class, templated over the "mode", which is either Binaryen2Binary (direct writing), Binaryen2Stack, or Stack2Binary. This avoids a lot of boilerplate as the 3 modes share a lot of code in overlapping ways. Stack IR does not support source maps / debug info. We just don't use that IR if debug info is present. A tiny text format comment (if emitting non-minified text) indicates stack IR is present, if it is ((; has Stack IR ;)). This may help with debugging, just in case people forget. There is also a pass to print out the stack IR for debug purposes, as mentioned above. The sieve binaryen.js test was actually not validating all along - these new opts broke it in a more noticeable manner. Fixed. Added extra checks in pass-debug mode, to verify that if stack IR should have been thrown out, it was. This should help avoid any confusion with the IR being invalid. Added a comment about the possible future of stack IR as the main IR, depending on optimization results, following some discussion earlier today.