Migrate winch-codegen to `wasmtime_environ::error` (#12297)

winch(aarch64): Simplify constant handling, part 1/N (#10888)

* winch(aarch64): implify constant handling, part 1/N

This commit is the first step toward simplifying constant handling,
particularly

winch(aarch64): Simplify constant handling, part 1/N (#10888)

* winch(aarch64): implify constant handling, part 1/N

This commit is the first step toward simplifying constant handling,
particularly for the aarch64 backend.

The main highlights in this patch are:

* Introduction of `ConstantPool` implemenetation on top of Cranlift
primitives. The implemettaion is identical to the existing for x64,
however, it's abstracted so that it can be easily consumed from any
existing backend.
* Usage of the constant pool from aarch64, which simplifies the
loading of constants, particularly floating point constants.

The main motivation behind this change is to _eventually_ detach the
implicit usage of the scatch register from constant loading as much as
possible, reducing the possibility of subtle bugs (like the one
described in https://github.com/bytecodealliance/wasmtime/pull/10829).

Note that I have a work-in-progress branch from where all these
changes are cherry picked from, to make everything easier to review.

A side effect of this change, is the improvement to the code
generation involving floating point constants. Prior to this change,
multiple moves were involved, with this patch, at most 1 move is
required and at worst one load is required.

* Update disassembly tests

* Apply refactored constant handling on top of shared float min/max implementation

* `fmt`

show more ...

winch: move reason for ignoring dead code (#10710)

This removes a clippy warning when running:

```
RUSTFLAGS='-D warnings' cargo clippy --workspace --exclude test-programs
```

Remove some `#![expect(clippy::allow_attributes_without_reason)]` (#10661)

Clean up some crates by migrating from `#[allow]` to `#[expect]`
(ideally) or `#[allow]`-with-reason

Start using `#[expect]` instead of `#[allow]` (#9696)

* Start using `#[expect]` instead of `#[allow]`

In Rust 1.81, our new MSRV, a new feature was added to Rust to use
`#[expect]` to control lint

Start using `#[expect]` instead of `#[allow]` (#9696)

* Start using `#[expect]` instead of `#[allow]`

In Rust 1.81, our new MSRV, a new feature was added to Rust to use
`#[expect]` to control lint levels. This new lint annotation will
silence a lint but will itself cause a lint if it doesn't actually
silence anything. This is quite useful to ensure that annotations don't
get stale over time.

Another feature is the ability to use a `reason` directive on the
attribute with a string explaining why the attribute is there. This
string is then rendered in compiler messages if a warning or error
happens.

This commit migrates applies a few changes across the workspace:

* Some `#[allow]` are changed to `#[expect]` with a `reason`.
* Some `#[allow]` have a `reason` added if the lint conditionally fires
(mostly related to macros).
* Some `#[allow]` are removed since the lint doesn't actually fire.
* The workspace configures `clippy::allow_attributes_without_reason = 'warn'`
as a "ratchet" to prevent future regressions.
* Many crates are annotated to allow `allow_attributes_without_reason`
during this transitionary period.

The end-state is that all crates should use
`#[expect(..., reason = "...")]` for any lint that unconditionally fires
but is expected. The `#[allow(..., reason = "...")]` lint should be used
for conditionally firing lints, primarily in macro-related code.
The `allow_attributes_without_reason = 'warn'` level is intended to be
permanent but the transitionary
`#[expect(clippy::allow_attributes_without_reason)]` crate annotations
to go away over time.

* Fix adapter build

prtest:full

* Fix one-core build of icache coherence

* Use `allow` for missing_docs

Work around rust-lang/rust#130021 which was fixed in Rust 1.83 and isn't
fixed for our MSRV at this time.

* More MSRV compat

show more ...

winch: Switch to using cranelift for all trampolines (#8109)

* Switch winch over to using cranelift for all trampolines

* Fix unused code warnings

* Fix unused code warnings

prtest:full

winch: Add a subset of known libcalls and improve call emission (#7228)

* winch: Add known a subset of known libcalls and improve call emission

This change is a follow up to:
- https://github.com/b

winch: Add a subset of known libcalls and improve call emission (#7228)

* winch: Add known a subset of known libcalls and improve call emission

This change is a follow up to:
- https://github.com/bytecodealliance/wasmtime/pull/7155
- https://github.com/bytecodealliance/wasmtime/pull/7035

One of the objectives of this change is to make it easy to emit
function calls at the MacroAssembler layer, for cases in which it's
challenging to know ahead-of-time if a particular functionality can be
achieved natively (e.g. rounding and SSE4.2). The original implementation
of function call emission, made this objective difficult to achieve and
it was also difficult to reason about.
I decided to simplify the overall approach to function calls as part of
this PR; in essence, the `call` module now exposes a single function
`FnCall::emit` which is reponsible of gathtering the dependencies and
orchestrating the emission of the call. This new approach deliberately
avoids holding any state regarding the function call for simplicity.

This change also standardizes the usage of `Callee` as the main
entrypoint for function call emission, as of this change 4 `Callee`
types exist (`Local`, `Builtin`, `Import`, `FuncRef`), each callee kind
is mappable to a `CalleeKind` which is the materialized version of
a callee which Cranelift understands.

This change also moves the creation of the `BuiltinFunctions` to the
`ISA` level given that they can be safely used accross multiple function
compilations.

Finally, this change also introduces support for some of the
"well-known" libcalls and hooks those libcalls at the
`MacroAssembler::float_round` callsite.

--

prtest:full

* Review comments

* Remove unnecessary `into_iter`

* Fix remaining lifetime parameter names

show more ...

Function references (#5288)

* Make wasmtime-types type check

* Make wasmtime-environ type check.

* Make wasmtime-runtime type check

* Make cranelift-wasm type check

* Make wasmtime-cranelift typ

Function references (#5288)

* Make wasmtime-types type check

* Make wasmtime-environ type check.

* Make wasmtime-runtime type check

* Make cranelift-wasm type check

* Make wasmtime-cranelift type check

* Make wasmtime type check

* Make wasmtime-wast type check

* Make testsuite compile

* Address Luna's comments

* Restore compatibility with effect-handlers/wasm-tools#func-ref-2

* Add function refs feature flag; support testing

* Provide function references support in helpers

- Always support Index in blocktypes
- Support Index as table type by pretending to be Func
- Etc

* Implement ref.as_non_null

* Add br_on_null

* Update Cargo.lock to use wasm-tools with peek

This will ultimately be reverted when we refer to
wasm-tools#function-references, which doesn't have peek, but does have type
annotations on CallRef

* Add call_ref

* Support typed function references in ref.null

* Implement br_on_non_null

* Remove extraneous flag; default func refs false

* Use IndirectCallToNull trap code for call_ref

* Factor common call_indirect / call_ref into a fn

* Remove copypasta clippy attribute / format

* Add a some more tests for typed table instructions

There certainly need to be many more, but this at least catches the bugs fixed
in the next commit

* Fix missing typed cases for table_grow, table_fill

* Document trap code; remove answered question

* Mark wasm-tools to wasmtime reftype infallible

* Fix reversed conditional

* Scope externref/funcref shorthands within WasmRefType

* Merge with upstream

* Make wasmtime compile again

* Fix warnings

* Remove Bot from the type algebra

* Fix table tests.

`wast::Cranelift::spec::function_references::table`
`wast::Cranelift::spec::function_references::table_pooling`

* Fix table{get,set} tests.

```
wast::Cranelift::misc::function_references::table_get
wast::Cranelift::misc::function_references::table_get_pooling
wast::Cranelift::misc::function_references::table_set
wast::Cranelift::misc::function_references::table_set_pooling
```

* Insert subtype check to fix local_get tests.

```
wast::Cranelift::spec::function_references::local_get
wast::Cranelift::spec::function_references::local_get_pooling
```

* Fix compilation of `br_on_non_null`.

The branch destinations were the other way round... :-)

Fixes the following test failures:
```
wast::Cranelift::spec::function_references::br_on_non_null
wast::Cranelift::spec::function_references::br_on_non_null_pooling
```

* Fix ref_as_non_null tests.

The test was failing due to the wrong error message being printed. As
per upstream folks' suggest we were using the trap code
`IndirectCallToNull`, but it produces an unexpected error message.

This commit reinstates the `NullReference` trap code. It produces the
expected error message. We will have to chat with the maintainers
upstream about how to handle these "test failures".

Fixes the following test failures:

```
wast::Cranelift::spec::function_references::ref_as_non_null
wast::Cranelift::spec::function_references::ref_as_non_null_pooling
```

* Fix a call_ref regression.

* Fix global tests.

Extend `is_matching_assert_invalid_error_message` to circumvent the textual error message failure.

Fixes the following test failures:
```
wast::Cranelift::spec::function_references::global
wast::Cranelift::spec::function_references::global_pooling
```

* Cargo update

* Update

* Spell out some cases in match_val

* Disgusting hack to subvert limitations of type reconstruction.

In the function `wasmtime::values::Val::ty()` attempts to reconstruct
the type of its underlying value purely based on the shape of the
value. With function references proposal this sort of reconstruction
is no longer complete as a source reference type may have been
nullable. Nullability is not inferrable by looking at the shape of the
runtime object alone.

Consequently, the runtime cannot reconstruct the type for
`Val::FuncRef` and `Val::ExternRef` by looking at their respective
shapes.

* Address workflows comments.

* null reference => null_reference for CLIF parsing compliance.

* Delete duplicate-loads-dynamic-memory-egraph (again)

* Idiomatic code change.

* Nullability subtyping + fix non-null storage check.

This commit removes the `hacky_eq` check in `func.rs`. Instead it is
replaced by a subtype check. This subtype check occurs in
`externals.rs` too.

This commit also fixes a bug. Previously, it was possible to store a
null reference into a non-null table cell. I have added to new test
cases for this bug: one for funcrefs and another for externrefs.

* Trigger unimplemented for typed function references. Format values.rs

* run cargo fmt

* Explicitly match on HeapType::Extern.

* Address cranelift-related feedback

* Remove PartialEq,Eq from ValType, RefType, HeapType.

* Pin wasmparser to a fairly recent commit.

* Run cargo fmt

* Ignore tail call tests.

* Remove garbage

* Revert changes to wasmtime public API.

* Run cargo fmt

* Get more CI passing (#19)

* Undo Cargo.lock changes

* Fix build of cranelift tests

* Implement link-time matches relation. Disable tests failing due to lack of public API support.

* Run cargo fmt

* Run cargo fmt

* Initial implementation of eager table initialization

* Tidy up eager table initialisation

* Cargo fmt

* Ignore type-equivalence test

* Replace TODOs with descriptive comments.

* Various changes found during review (#21)

* Clarify a comment

This isn't only used for null references

* Resolve a TODO in local init

Don't initialize non-nullable locals to null, instead skip
initialization entirely and wasm validation will ensure it's always
initialized in the scope where it's used.

* Clarify a comment and skipping the null check.

* Remove a stray comment

* Change representation of `WasmHeapType`

Use a `SignatureIndex` instead of a `u32` which while not 100% correct
should be more correct. This additionally renames the `Index` variant to
`TypedFunc` to leave space for future types which aren't functions to
not all go into an `Index` variant.

This required updates to Winch because `wasmtime_environ` types can no
longer be converted back to their `wasmparser` equivalents. Additionally
this means that all type translation needs to go through some form of
context to resolve indices which is now encapsulated in a `TypeConvert`
trait implemented in various locations.

* Refactor table initialization

Reduce some duplication and simplify some data structures to have a more
direct form of table initialization and a bit more graceful handling of
element-initialized tables. Additionally element-initialize tables are
now treated the same as if there's a large element segment initializing
them.

* Clean up some unrelated chagnes

* Simplify Table bindings slightly

* Remove a no-longer-needed TODO

* Add a FIXME for `SignatureIndex` in `WasmHeapType`

* Add a FIXME for panicking on exposing function-references types

* Fix a warning on nightly

* Fix tests for winch and cranelift

* Cargo fmt

* Fix arity mismatch in aarch64/abi

---------

Co-authored-by: Daniel Hillerström <[email protected]>
Co-authored-by: Daniel Hillerström <[email protected]>
Co-authored-by: Alex Crichton <[email protected]>

show more ...

winch: Drop `FuncEnv` trait (#6443)

This commit is a small cleanup to drop the usage of the `FuncEnv` trait.

In https://github.com/bytecodealliance/wasmtime/pull/6358, we agreed on
making `winch-co

winch: Drop `FuncEnv` trait (#6443)

This commit is a small cleanup to drop the usage of the `FuncEnv` trait.

In https://github.com/bytecodealliance/wasmtime/pull/6358, we agreed on
making `winch-codegen` directly depend on `wasmtime-environ`.

Introducing a direct relatioship between `winch-codegen` and
`wasmtime-environ` means that the `FuncEnv` trait is no longer serving
its original purpose, and we can drop the usage of the trait and use the
types exposed from `winch-codegen` directly instead.

Even though this change drops the `FuncEnv` trait, it still keeps
a `FuncEnv` struct, which is used during code generation.

show more ...

winch: Implement new trampolines (#6358)

* winch: Implement new trampolines

This change is a follow-up to
https://github.com/bytecodealliance/wasmtime/pull/6262, in which the new
trampolines, descr

winch: Implement new trampolines (#6358)

* winch: Implement new trampolines

This change is a follow-up to
https://github.com/bytecodealliance/wasmtime/pull/6262, in which the new
trampolines, described [here](https://github.com/bytecodealliance/rfcs/blob/main/accepted/tail-calls.md#new-trampolines-and-vmcallercheckedanyfunc-changes),
were introduced to Wasmtime.

This change, focuses on the `array-to-wasm`,
`native-to-wasm` and `wasm-to-native` trampolines to restore Winch's
working state prior to the introduction of the new trampolines. It's
worth noting that the new approach for trampolines make it easier to support
the `TypedFunc` API in Winch. Prior to the introduction of the new
trampolines, it was not obvious how to approach it.

This change also introduces a pinned register that will hold the
`VMContext` pointer, which is loaded in the `*-to-wasm` trampolines;
the `VMContext` register is a pre-requisite to this change to support
the `wasm-to-native` trampolines.

Lastly, with the introduction of the `VMContext` register and the
`wasm-to-native` trampolines, this change also introduces support for
calling function imports, which is a variation of the already existing
calls to locally defined functions.

The other notable piece of this change aside from the trampolines is
`winch-codegen`'s dependency on `wasmtime-environ`. Winch is so closely
tied to the concepts exposed by the wasmtime crates that it makes sense
to tie them together, even though the separation provides some
advantages like easier testing in some cases, in the long run, there's
probably going to be less need to test Winch in isolation and rather
we'd rely more on integration style tests which require all of Wasmtime
pieces anyway (fuzzing, spec tests, etc).

This change doesn't update the existing implmenetation of
`winch_codegen::FuncEnv`, but the intention is to update that part after
this change.

prtest:full

* tests: Ignore miri in Winch integration tests

* Remove hardcoded alignment and addend

show more ...

winch: Initial integration with wasmtime (#6119)

* Adding in trampoline compiling method for ISA

* Adding support for indirect call to memory address

* Refactoring frame to externalize defined loc

winch: Initial integration with wasmtime (#6119)

* Adding in trampoline compiling method for ISA

* Adding support for indirect call to memory address

* Refactoring frame to externalize defined locals, so it removes WASM depedencies in trampoline case

* Adding initial version of trampoline for testing

* Refactoring trampoline to be re-used by other architectures

* Initial wiring for winch with wasmtime

* Add a Wasmtime CLI option to select `winch`

This is effectively an option to select the `Strategy` enumeration.

* Implement `Compiler::compile_function` for Winch

Hook this into the `TargetIsa::compile_function` hook as well. Currently
this doesn't take into account `Tunables`, but that's left as a TODO for
later.

* Filling out Winch append_code method

* Adding back in changes from previous branch

Most of these are a WIP. It's missing trampolines for x64, but a basic
one exists for aarch64. It's missing the handling of arguments that
exist on the stack.

It currently imports `cranelift_wasm::WasmFuncType` since it's what's
passed to the `Compiler` trait. It's a bit awkward to use in the
`winch_codegen` crate since it mostly operates on `wasmparser` types.
I've had to hack in a conversion to get things working. Long term, I'm
not sure it's wise to rely on this type but it seems like it's easier on
the Cranelift side when creating the stub IR.

* Small API changes to make integration easier

* Adding in new FuncEnv, only a stub for now

* Removing unneeded parts of the old PoC, and refactoring trampoline code

* Moving FuncEnv into a separate file

* More comments for trampolines

* Adding in winch integration tests for first pass

* Using new addressing method to fix stack pointer error

* Adding test for stack arguments

* Only run tests on x86 for now, it's more complete for winch

* Add in missing documentation after rebase

* Updating based on feedback in draft PR

* Fixing formatting on doc comment for argv register

* Running formatting

* Lock updates, and turning on winch feature flags during tests

* Updating configuration with comments to no longer gate Strategy enum

* Using the winch-environ FuncEnv, but it required changing the sig

* Proper comment formatting

* Removing wasmtime-winch from dev-dependencies, adding the winch feature makes this not necessary

* Update doc attr to include winch check

* Adding winch feature to doc generation, which seems to fix the feature error in CI

* Add the `component-model` feature to the cargo doc invocation in CI

To match the metadata used by the docs.rs invocation when building docs.

* Add a comment clarifying the usage of `component-model` for docs.rs

* Correctly order wasmtime-winch and winch-environ in the publish script

* Ensure x86 test dependencies are included in cfg(target_arch)

* Further constrain Winch tests to x86_64 _and_ unix

---------

Co-authored-by: Alex Crichton <[email protected]>
Co-authored-by: Saúl Cabrera <[email protected]>

show more ...

winch: Introduce `winch-environ` (#6017)

This commit introduces the `winch-environ` crate. This crate's responsibility is
to provide a shared implementatation of the `winch_codegen::FuncEnv` trait,

winch: Introduce `winch-environ` (#6017)

This commit introduces the `winch-environ` crate. This crate's responsibility is
to provide a shared implementatation of the `winch_codegen::FuncEnv` trait,
which is Winch's function compilation environment, used to resolve module and
runtime specific information needed by the code generation, such as resolving
all the details about a callee in a WebAssembly module, or resolving specific
information from the `VMContext`.

As of this change, the implementation only includes the necessary pieces to
resolve a function callee in a WebAssembly module. The idea is to evolve the
`winch_codegen::FuncEnv` trait as we evolve Winch's code generation.

show more ...

winch: Use cranelift-codegen x64 backend for emission. (#5581)

This change substitutes the string based emission mechanism with
cranelift-codegen's x64 backend.

This change _does not_:

* Intr

winch: Use cranelift-codegen x64 backend for emission. (#5581)

This change substitutes the string based emission mechanism with
cranelift-codegen's x64 backend.

This change _does not_:

* Introduce new functionality in terms of supported instructions.
* Change the semantics of the assembler/macroassembler in terms of the logic to
emit instructions.

The most notable differences between this change and the previous version are:

* Handling of shared flags and ISA-specific flags, which for now are left with
the default value.
* Simplification of instruction emission per operand size: previously the
assembler defined different methods depending on the operand size (e.g. `mov`
for 64 bits, and `movl` for 32 bits). This change updates such approach so that
each assembler method takes an operand size as a parameter, reducing duplication
and making the code more concise and easier to integrate with the x64's `Inst` enum.
* Introduction of a disassembler for testing purposes.

As of this change, Winch generates the following code for the following test
programs:

```wat
(module
(export "main" (func $main))

(func $main (result i32)
(i32.const 10)
(i32.const 20)
i32.add
))
```

```asm
0: 55 push rbp
1: 48 89 e5 mov rbp, rsp
4: b8 0a 00 00 00 mov eax, 0xa
9: 83 c0 14 add eax, 0x14
c: 5d pop rbp
d: c3 ret
```

```wat
(module
(export "main" (func $main))

(func $main (result i32)
(local $foo i32)
(local $bar i32)
(i32.const 10)
(local.set $foo)
(i32.const 20)
(local.set $bar)

(local.get $foo)
(local.get $bar)
i32.add
))
```

```asm
0: 55 push rbp
1: 48 89 e5 mov rbp, rsp
4: 48 83 ec 08 sub rsp, 8
8: 48 c7 04 24 00 00 00 00 mov qword ptr [rsp], 0
10: b8 0a 00 00 00 mov eax, 0xa
15: 89 44 24 04 mov dword ptr [rsp + 4], eax
19: b8 14 00 00 00 mov eax, 0x14
1e: 89 04 24 mov dword ptr [rsp], eax
21: 8b 04 24 mov eax, dword ptr [rsp]
24: 8b 4c 24 04 mov ecx, dword ptr [rsp + 4]
28: 01 c1 add ecx, eax
2a: 48 89 c8 mov rax, rcx
2d: 48 83 c4 08 add rsp, 8
31: 5d pop rbp
32: c3 ret
```

```wat
(module
(export "main" (func $main))

(func $main (param i32) (param i32) (result i32)
(local.get 0)
(local.get 1)
i32.add
))
```

```asm
0: 55 push rbp
1: 48 89 e5 mov rbp, rsp
4: 48 83 ec 08 sub rsp, 8
8: 89 7c 24 04 mov dword ptr [rsp + 4], edi
c: 89 34 24 mov dword ptr [rsp], esi
f: 8b 04 24 mov eax, dword ptr [rsp]
12: 8b 4c 24 04 mov ecx, dword ptr [rsp + 4]
16: 01 c1 add ecx, eax
18: 48 89 c8 mov rax, rcx
1b: 48 83 c4 08 add rsp, 8
1f: 5d pop rbp
20: c3 ret
```

show more ...

Initial skeleton for Winch (#4907)

* Initial skeleton for Winch

This commit introduces the initial skeleton for Winch, the "baseline"
compiler.

This skeleton contains mostly setup code for th

Initial skeleton for Winch (#4907)

* Initial skeleton for Winch

This commit introduces the initial skeleton for Winch, the "baseline"
compiler.

This skeleton contains mostly setup code for the ISA, ABI, registers,
and compilation environment abstractions. It also includes the
calculation of function local slots.

As of this commit, the structure of these abstractions looks like the
following:

+------------------------+
| v
+----------+ +-----+ +-----------+-----+-----------------+
| Compiler | --> | ISA | --> | Registers | ABI | Compilation Env |
+----------+ +-----+ +-----------+-----+-----------------+
| ^
+------------------------------+

* Compilation environment will hold a reference to the function data

* Add basic documentation to the ABI trait

* Enable x86 and arm64 in cranelift-codegen

* Add reg_name function for x64

* Introduce the concept of a MacroAssembler and Assembler

This commit introduces the concept of a MacroAsesembler and
Assembler. The MacroAssembler trait will provide a high enough
interface across architectures so that each ISA implementation can use their own low-level
Assembler implementation to fulfill the interface. Each Assembler will
provide a 1-1 mapping to each ISA instruction.

As of this commit, only a partial debug implementation is provided for
the x64 Assembler.

* Add a newtype over PReg

Adds a newtype `Reg` over regalloc2::PReg; this ensures that Winch
will operate only on the concept of `Reg`. This change is temporary
until we have the necessary machinery to share a common Reg
abstraction via `cranelift_asm`

* Improvements to local calcuation

- Add `LocalSlot::addressed_from_sp`
- Use `u32` for local slot and local sizes calculation

* Add helper methods to ABIArg

Adds helper methods to retrieve register and type information from the argument

* Make locals_size public in frame

* Improve x64 register naming depending on size

* Add new methods to the masm interface

This commit introduces the ability for the MacroAssembler to reserve
stack space, get the address of a given local and perform a stack
store based on the concept of `Operand`s.

There are several motivating factors to introduce the concept of an
Operand:

- Make the translation between Winch and Cranelift easier;
- Make dispatching from the MacroAssembler to the underlying Assembler
- easier by minimizing the amount of functions that we need to define
- in order to satisfy the store/load combinations

This commit also introduces the concept of a memory address, which
essentially describes the addressing modes; as of this commit only one
addressing mode is supported. We'll also need to verify that this
structure will play nicely with arm64.

* Blank masm implementation for arm64

* Implementation of reserve_stack, local_address, store and fp_offset
for x64

* Implement function prologue and argument register spilling

* Add structopt and wat

* Fix debug instruction formatting

* Make TargetISA trait publicly accessible

* Modify the MacroAssembler finalize siganture to return a slice of strings

* Introduce a simple CLI for Winch

To be able to compile Wasm programs with Winch independently. Mostly
meant for testing / debugging

* Fix bug in x64 assembler mov_rm

* Remove unused import

* Move the stack slot calculation to the Frame

This commit moves the calculation of the stack slots to the frame
handler abstraction and also includes the calculation of the limits
for the function defined locals, which will be used to zero the locals
that are not associated to function arguments

* Add i32 and i64 constructors to local slots

* Introduce the concept of DefinedLocalsRange

This commit introduces `DefinedLocalsRange` to track the stack offset
at which the function-defined locals start and end; this is later used
to zero-out that stack region

* Add constructors for int and float registers

* Add a placeholder stack implementation

* Add a regset abstraction to track register availability

Adds a bit set abstraction to track register availability for register
allocation.

The bit set has no specific knowledge about physical registers, it
works on the register's hardware encoding as the source of truth.

Each RegSet is expected to be created with the universe of allocatable
registers per ISA when starting the compilation of a particular function.

* Add an abstraction over register and immediate

This is meant to be used as the source for stores.

* Add a way to zero local slots and an initial skeletion of regalloc

This commit introduces `zero_local_slots` to the MacroAssembler; which
ensures that function defined locals are zeroed out when starting the
function body.

The algorithm divides the defined function locals stack range
into 8 byte slots and stores a zero at each address. This process
relies on register allocation if the amount of slots that need to be
initialized is greater than 1. In such case, the next available
register is requested to the register set and it's used to store a 0,
which is then stored at every local slot

* Update to wasmparser 0.92

* Correctly track if the regset has registers available

* Add a result entry to the ABI signature

This commuit introduces ABIResult as part of the ABISignature;
this struct will track how function results are stored; initially it
will consiste of a single register that will be requested to the
register allocator at the end of the function; potentially causing a spill

* Move zero local slots and add more granular methods to the masm

This commit removes zeroing local slots from the MacroAssembler and
instead adds more granular methods to it (e.g `zero`, `add`).

This allows for better code sharing since most of the work done by the
algorithm for zeroing slots will be the same in all targets, except
for the binary emissions pieces, which is what gets delegated to the masm

* Use wasmparser's visitor API and add initial support for const and add

This commit adds initial support for the I32Const and I32
instructions; this involves adding a minimum for register
allocation. Note that some regalloc pieces are still incomplete, since
for the current set of supported instructions they are not needed.

* Make the ty field public in Local

* Add scratch_reg to the abi

* Add a method to get a particular local from the Frame

* Split the compilation environment abstraction

This commit splits the compilation environment into two more concise
abstractions:

1. CodeGen: the main abstraction for code generation
2. CodeGenContext: abstraction that shares the common pieces for
compilation; these pieces are shared between the code generator and
the register allocator

* Add `push` and `load` to the MacroAssembler

* Remove dead code warnings for unused paths

* Map ISA features to cranelift-codegen ISA features

* Apply formatting

* Fix Cargo.toml after a bad rebase

* Add component-compiler feature

* Use clap instead of structopt

* Add winch to publish.rs script

* Minor formatting

* Add tests to RegSet and fix two bugs when freeing and checking for
register availability

* Add tests to Stack

* Free source register after a non-constant i32 add

* Improve comments

- Remove unneeded comments
- And improve some of the TODO items

* Update default features

* Drop the ABI generic param and pass the word_size information directly

To avoid dealing with dead code warnings this commit passes the word
size information directly, since it's the only piece of information
needed from the ABI by Codegen until now

* Remove dead code

This piece of code will be put back once we start integrating Winch
with Wasmtime

* Remove unused enum variant

This variant doesn't get constructed; it should be added back once a
backend is added and not enabled by default or when Winch gets
integrated into Wasmtime

* Fix unused code in regset tests

* Update spec testsuite

* Switch the visitor pattern for a simpler operator match

This commit removes the usage of wasmparser's visitor pattern and
instead defaults to a simpler operator matching approach. This removes
the complexity of having to define all the visitor trait functions at once.

* Use wasmparser's Visitor trait with a different macro strategy

This commit puts back wasmparser's Visitor trait, with a sigle;
simpler macro, only used for unsupported operators.

* Restructure Winch

This commit restuructures Winch's parts. It divides the initial
approach into three main crates: `winch-codegen`,`wasmtime-winch` and `winch-tools`.

`wasmtime-winch` is reponsible for the Wasmtime-Winch integration.
`winch-codegen` is solely responsible for code generation.
`winch-tools` is CLI tool to compile Wasm programs, mainly for testing purposes.

* Refactor zero local slots

This commit moves the logic of zeroing local slots from the codegen
module into a method with a default implementation in the
MacroAssembler trait: `zero_mem_range`.

The refactored implementation is very similar to the previous
implementation with the only difference
that it doesn't allocates a general-purpose register; it instead uses
the register allocator to retrieve the scratch register and uses this
register to unroll the series of zero stores.

* Tie the codegen creation to the ISA ABI

This commit makes the relationship between the ISA ABI and the codegen
explicit. This allows us to pass down ABI-specific bit and pieces to
the codegeneration. In this case the only concrete piece that we need
is the ABI word size.

* Mark winch as publishable directory

* Revamp winch docs

This commit ensures that all the code comments in Winch are compliant
with the syle used in the rest of Wasmtime's codebase.

It also imptoves, generally the quality of the comments in some modules.

* Panic when using multi-value when the target is aarch64

Similar to x64, this commit ensures that the abi signature of the
current function doesn't use multi-value returns

* Document the usage of directives

* Use endianness instead of endianess in the ISA trait

* Introduce a three-argument form in the MacroAssembler

This commit introduces the usage of three-argument form for the
MacroAssembler interface. This allows for a natural mapping for
architectures like aarch64. In the case of x64, the implementation can
simply restrict the implementation asserting for equality in two of
the arguments of defaulting to a differnt set of instructions.

As of this commit, the implementation of `add` panics if the
destination and the first source arguments are not equal; internally
the x64 assembler implementation will ensure that all the allowed
combinations of `add` are satisfied. The reason for panicking and not
emitting a `mov` followed by an `add` for example is simply because register
allocation happens right before calling `add`, which ensures any
register-to-register moves, if needed.

This implementation will evolve in the future and this panic will be
lifted if needed.

* Improve the documentation for the MacroAssembler.

Documents the usage of three-arg form and the intention around the
high-level interface.

* Format comments in remaining modules

* Clean up Cargo.toml for winch pieces

This commit adds missing fields to each of Winch's Cargo.toml.

* Use `ModuleTranslation::get_types()` to derive the function type

* Assert that start range is always word-size aligned

show more ...