Add a new type BlockCall that represents the pair of a block name with arguments to be passed to it. (The mnemonic here is that it looks a bit like a function call.) Rework the implementation of jump, brz, and brnz to use BlockCall instead of storing the block arguments as varargs in the instruction's ValueList.
To ensure that we're processing block arguments from BlockCall values in instructions, three new functions have been introduced on DataFlowGraph that both sets of arguments:
inst_values - returns an iterator that traverses values in the instruction and block arguments
map_inst_values - applies a function to each value in the instruction and block arguments
overwrite_inst_values - overwrite all values in an instruction and block arguments with values from the iterator
Co-authored-by: Jamey Sharp <jamey@minilop.net>
We have some operations defined on DataFlowGraph purely to work around borrow-checker issues with InstructionData and other data on DataFlowGraph. Part of the problem is that indexing the DFG directly hides the fact that we're only indexing the insts field of the DFG.
This PR makes the insts field of the DFG public, but wraps it in a newtype that only allows indexing. This means that the borrow checker is better able to tell when operations on memory held by the DFG won't conflict, which comes up frequently when mutating ValueLists held by InstructionData.
* egraph support: rewrite to work in terms of CLIF data structures.
This work rewrites the "egraph"-based optimization framework in
Cranelift to operate on aegraphs (acyclic egraphs) represented in the
CLIF itself rather than as a separate data structure to which and from
which we translate the CLIF.
The basic idea is to add a new kind of value, a "union", that is like an
alias but refers to two other values rather than one. This allows us to
represent an eclass of enodes (values) as a tree. The union node allows
for a value to have *multiple representations*: either constituent value
could be used, and (in well-formed CLIF produced by correct
optimization rules) they must be equivalent.
Like the old egraph infrastructure, we take advantage of acyclicity and
eager rule application to do optimization in a single pass. Like before,
we integrate GVN (during the optimization pass) and LICM (during
elaboration).
Unlike the old egraph infrastructure, everything stays in the
DataFlowGraph. "Pure" enodes are represented as instructions that have
values attached, but that are not placed into the function layout. When
entering "egraph" form, we remove them from the layout while optimizing.
When leaving "egraph" form, during elaboration, we can place an
instruction back into the layout the first time we elaborate the enode;
if we elaborate it more than once, we clone the instruction.
The implementation performs two passes overall:
- One, a forward pass in RPO (to see defs before uses), that (i) removes
"pure" instructions from the layout and (ii) optimizes as it goes. As
before, we eagerly optimize, so we form the entire union of optimized
forms of a value before we see any uses of that value. This lets us
rewrite uses to use the most "up-to-date" form of the value and
canonicalize and optimize that form.
The eager rewriting and acyclic representation make each other work
(we could not eagerly rewrite if there were cycles; and acyclicity
does not miss optimization opportunities only because the first time
we introduce a value, we immediately produce its "best" form). This
design choice is also what allows us to avoid the "parent pointers"
and fixpoint loop of traditional egraphs.
This forward optimization pass keeps a scoped hashmap to "intern"
nodes (thus performing GVN), and also interleaves on a per-instruction
level with alias analysis. The interleaving with alias analysis allows
alias analysis to see the most optimized form of each address (so it
can see equivalences), and allows the next value to see any
equivalences (reuses of loads or stored values) that alias analysis
uncovers.
- Two, a forward pass in domtree preorder, that "elaborates" pure enodes
back into the layout, possibly in multiple places if needed. This
tracks the loop nest and hoists nodes as needed, performing LICM as it
goes. Note that by doing this in forward order, we avoid the
"fixpoint" that traditional LICM needs: we hoist a def before its
uses, so when we place a node, we place it in the right place the
first time rather than moving later.
This PR replaces the old (a)egraph implementation. It removes both the
cranelift-egraph crate and the logic in cranelift-codegen that uses it.
On `spidermonkey.wasm` running a simple recursive Fibonacci
microbenchmark, this work shows 5.5% compile-time reduction and 7.7%
runtime improvement (speedup).
Most of this implementation was done in (very productive) pair
programming sessions with Jamey Sharp, thus:
Co-authored-by: Jamey Sharp <jsharp@fastly.com>
* Review feedback.
* Review feedback.
* Review feedback.
* Bugfix: cprop rule: `(x + k1) - k2` becomes `x - (k2 - k1)`, not `x - (k1 - k2)`.
Co-authored-by: Jamey Sharp <jsharp@fastly.com>
Remove the boolean types from cranelift, and the associated instructions breduce, bextend, bconst, and bint. Standardize on using 1/0 for the return value from instructions that produce scalar boolean results, and -1/0 for boolean vector elements.
Fixes#3205
Co-authored-by: Afonso Bordado <afonso360@users.noreply.github.com>
Co-authored-by: Ulrich Weigand <ulrich.weigand@de.ibm.com>
Co-authored-by: Chris Fallin <chris@cfallin.org>
* Leverage Cargo's workspace inheritance feature
This commit is an attempt to reduce the complexity of the Cargo
manifests in this repository with Cargo's workspace-inheritance feature
becoming stable in Rust 1.64.0. This feature allows specifying fields in
the root workspace `Cargo.toml` which are then reused throughout the
workspace. For example this PR shares definitions such as:
* All of the Wasmtime-family of crates now use `version.workspace =
true` to have a single location which defines the version number.
* All crates use `edition.workspace = true` to have one default edition
for the entire workspace.
* Common dependencies are listed in `[workspace.dependencies]` to avoid
typing the same version number in a lot of different places (e.g. the
`wasmparser = "0.89.0"` is now in just one spot.
Currently the workspace-inheritance feature doesn't allow having two
different versions to inherit, so all of the Cranelift-family of crates
still manually specify their version. The inter-crate dependencies,
however, are shared amongst the root workspace.
This feature can be seen as a method of "preprocessing" of sorts for
Cargo manifests. This will help us develop Wasmtime but shouldn't have
any actual impact on the published artifacts -- everything's dependency
lists are still the same.
* Fix wasi-crypto tests
This commit replaces #4869 and represents the actual version bump that
should have happened had I remembered to bump the in-tree version of
Wasmtime to 1.0.0 prior to the branch-cut date. Alas!
* Upgrade all crates to the Rust 2021 edition
I've personally started using the new format strings for things like
`panic!("some message {foo}")` or similar and have been upgrading crates
on a case-by-case basis, but I think it probably makes more sense to go
ahead and blanket upgrade everything so 2021 features are always
available.
* Fix compile of the C API
* Fix a warning
* Fix another warning
* Bump to 0.36.0
* Add a two-week delay to Wasmtime's release process
This commit is a proposal to update Wasmtime's release process with a
two-week delay from branching a release until it's actually officially
released. We've had two issues lately that came up which led to this proposal:
* In #3915 it was realized that changes just before the 0.35.0 release
weren't enough for an embedding use case, but the PR didn't meet the
expectations for a full patch release.
* At Fastly we were about to start rolling out a new version of Wasmtime
when over the weekend the fuzz bug #3951 was found. This led to the
desire internally to have a "must have been fuzzed for this long"
period of time for Wasmtime changes which we felt were better
reflected in the release process itself rather than something about
Fastly's own integration with Wasmtime.
This commit updates the automation for releases to unconditionally
create a `release-X.Y.Z` branch on the 5th of every month. The actual
release from this branch is then performed on the 20th of every month,
roughly two weeks later. This should provide a period of time to ensure
that all changes in a release are fuzzed for at least two weeks and
avoid any further surprises. This should also help with any last-minute
changes made just before a release if they need tweaking since
backporting to a not-yet-released branch is much easier.
Overall there are some new properties about Wasmtime with this proposal
as well:
* The `main` branch will always have a section in `RELEASES.md` which is
listed as "Unreleased" for us to fill out.
* The `main` branch will always be a version ahead of the latest
release. For example it will be bump pre-emptively as part of the
release process on the 5th where if `release-2.0.0` was created then
the `main` branch will have 3.0.0 Wasmtime.
* Dates for major versions are automatically updated in the
`RELEASES.md` notes.
The associated documentation for our release process is updated and the
various scripts should all be updated now as well with this commit.
* Add notes on a security patch
* Clarify security fixes shouldn't be previewed early on CI
* Wasmtime 0.15.0 and Cranelift 0.62.0. (#1398)
* Bump more ad-hoc versions.
* Add build.rs to wasi-common's Cargo.toml.
* Update the env var name in more places.
* Remove a redundant echo.
This patch updates or removes all references to the Cranelift repository. It affects links in README documents, issues that were transferred to the Wasmtime repository, CI badges, and a small bunch of sundry items.
Update the documentation for the merger, and also for various changes in
Cranelift. Remove some old obsolete documentation, and convert the remaining
Sphinx files to Markdown. Some of the remaining content is still out of
date, but this is a step forward.
* Manually rename BasicBlock to BlockPredecessor
BasicBlock is a pair of (Ebb, Inst) that is used to represent the
basic block subcomponent of an Ebb that is a predecessor to an Ebb.
Eventually we will be able to remove this struct, but for now it
makes sense to give it a non-conflicting name so that we can start
to transition Ebb to represent a basic block.
I have not updated any comments that refer to BasicBlock, as
eventually we will remove BlockPredecessor and replace with Block,
which is a basic block, so the comments will become correct.
* Manually rename SSABuilder block types to avoid conflict
SSABuilder has its own Block and BlockData types. These along with
associated identifier will cause conflicts in a later commit, so
they are renamed to be more verbose here.
* Automatically rename 'Ebb' to 'Block' in *.rs
* Automatically rename 'EBB' to 'block' in *.rs
* Automatically rename 'ebb' to 'block' in *.rs
* Automatically rename 'extended basic block' to 'basic block' in *.rs
* Automatically rename 'an basic block' to 'a basic block' in *.rs
* Manually update comment for `Block`
`Block`'s wikipedia article required an update.
* Automatically rename 'an `Block`' to 'a `Block`' in *.rs
* Automatically rename 'extended_basic_block' to 'basic_block' in *.rs
* Automatically rename 'ebb' to 'block' in *.clif
* Manually rename clif constant that contains 'ebb' as substring to avoid conflict
* Automatically rename filecheck uses of 'EBB' to 'BB'
'regex: EBB' -> 'regex: BB'
'$EBB' -> '$BB'
* Automatically rename 'EBB' 'Ebb' to 'block' in *.clif
* Automatically rename 'an block' to 'a block' in *.clif
* Fix broken testcase when function name length increases
Test function names are limited to 16 characters. This causes
the new longer name to be truncated and fail a filecheck test. An
outdated comment was also fixed.
