Commit Graph

504 Commits

Author SHA1 Message Date
Andrew Brown
c9e8889d47 Update clippy annotation to use latest version (#2375) 2020-11-09 09:24:59 -06:00
Alex Crichton
77827a48a9 Start compiling module-linking modules (#2093)
This commit is intended to be the first of many in implementing the
module linking proposal. At this time this builds on #2059 so it
shouldn't land yet. The goal of this commit is to compile bare-bones
modules which use module linking, e.g. those with nested modules.

My hope with module linking is that almost everything in wasmtime only
needs mild refactorings to handle it. The goal is that all per-module
structures are still per-module and at the top level there's just a
`Vec` containing a bunch of modules. That's implemented currently where
`wasmtime::Module` contains `Arc<[CompiledModule]>` and an index of
which one it's pointing to. This should enable
serialization/deserialization of any module in a nested modules
scenario, no matter how you got it.

Tons of features of the module linking proposal are missing from this
commit. For example instantiation flat out doesn't work, nor does
import/export of modules or instances. That'll be coming as future
commits, but the purpose here is to start laying groundwork in Wasmtime
for handling lots of modules in lots of places.
2020-11-06 13:32:30 -06:00
Alex Crichton
e659d5cecd Add initial support for the multi-memory proposal (#2263)
This commit adds initial (gated) support for the multi-memory wasm
proposal. This was actually quite easy since almost all of wasmtime
already expected multi-memory to be implemented one day. The only real
substantive change is the `memory.copy` intrinsic changes, which now
accounts for the source/destination memories possibly being different.
2020-10-13 19:13:52 -05:00
Alex Crichton
2c6841041d Validate modules while translating (#2059)
* Validate modules while translating

This commit is a change to cranelift-wasm to validate each function body
as it is translated. Additionally top-level module translation functions
will perform module validation. This commit builds on changes in
wasmparser to perform module validation interwtwined with parsing and
translation. This will be necessary for future wasm features such as
module linking where the type behind a function index, for example, can
be far away in another module. Additionally this also brings a nice
benefit where parsing the binary only happens once (instead of having an
up-front serial validation step) and validation can happen in parallel
for each function.

Most of the changes in this commit are plumbing to make sure everything
lines up right. The major functional change here is that module
compilation should be faster by validating in parallel (or skipping
function validation entirely in the case of a cache hit). Otherwise from
a user-facing perspective nothing should be that different.

This commit does mean that cranelift's translation now inherently
validates the input wasm module. This means that the Spidermonkey
integration of cranelift-wasm will also be validating the function as
it's being translated with cranelift. The associated PR for wasmparser
(bytecodealliance/wasmparser#62) provides the necessary tools to create
a `FuncValidator` for Gecko, but this is something I'll want careful
review for before landing!

* Read function operators until EOF

This way we can let the validator take care of any issues with
mismatched `end` instructions and/or trailing operators/bytes.
2020-10-05 11:02:01 -05:00
Alex Crichton
693c6ea771 wasmtime: Extract cranelift/lightbeam compilers to separate crates (#2117)
This commit extracts the two implementations of `Compiler` into two
separate crates, `wasmtime-cranelfit` and `wasmtime-lightbeam`. The
`wasmtime-jit` crate then depends on these two and instantiates them
appropriately. The goal here is to start reducing the weight of the
`wasmtime-environ` crate, which currently serves as a common set of
types between all `wasmtime-*` crates. Long-term I'd like to remove the
dependency on Cranelift from `wasmtime-environ`, but that's going to
take a lot more work.

In the meantime I figure it's a good way to get started by separating
out the lightbeam/cranelift function compilers from the
`wasmtime-environ` crate. We can continue to iterate on moving things
out in the future, too.
2020-08-20 11:34:31 +02:00
Nick Fitzgerald
5f36d7eab7 Merge pull request #2118 from fitzgen/enable-ref-types-by-default
Enable ref types and bulk memory operations by default
2020-08-07 17:41:05 -07:00
Nick Fitzgerald
94e4bad1e0 Enable reference types and bulk memory operations by default 2020-08-07 16:54:51 -07:00
Alex Crichton
08f9eb1725 Making caching support optional in Wasmtime (#2119)
This commit moves all of the caching support that currently lives in
`wasmtime-environ` into a `wasmtime-cache` crate and makes it optional. The
goal here is to slim down the `wasmtime-environ` crate and clearly separate
boundaries where caching is a standalone and optional feature, not intertwined
with other crates.
2020-08-07 15:42:40 -05:00
Alex Crichton
65eaca35dd Refactor where results of compilation are stored (#2086)
* Refactor where results of compilation are stored

This commit refactors the internals of compilation in Wasmtime to change
where results of individual function compilation are stored. Previously
compilation resulted in many maps being returned, and compilation
results generally held all these maps together. This commit instead
switches this to have all metadata stored in a `CompiledFunction`
instead of having a separate map for each item that can be stored.

The motivation for this is primarily to help out with future
module-linking-related PRs. What exactly "module level" is depends on
how we interpret modules and how many modules are in play, so it's a bit
easier for operations in wasmtime to work at the function level where
possible. This means that we don't have to pass around multiple
different maps and a function index, but instead just one map or just
one entry representing a compiled function.

Additionally this change updates where the parallelism of compilation
happens, pushing it into `wasmtime-jit` instead of `wasmtime-environ`.
This is another goal where `wasmtime-jit` will have more knowledge about
module-level pieces with module linking in play. User-facing-wise this
should be the same in terms of parallel compilation, though.

The ultimate goal of this refactoring is to make it easier for the
results of compilation to actually be a set of wasm modules. This means
we won't be able to have a map-per-metadata where the primary key is the
function index, because there will be many modules within one "object
file".

* Don't clear out fields, just don't store them

Persist a smaller set of fields in `CompilationArtifacts` instead of
trying to clear fields out and dynamically not accessing them.
2020-08-03 12:20:51 -05:00
Alex Crichton
026fb8d388 Don't re-parse wasm for debuginfo (#2085)
* Don't re-parse wasm for debuginfo

This commit updates debuginfo parsing to happen during the main
translation of the original wasm module. This avoid re-parsing the wasm
module twice (at least the section-level headers). Additionally this
ties debuginfo directly to a `ModuleTranslation` which makes it easier
to process debuginfo for nested modules in the upcoming module linking
proposal.

The changes here are summarized by taking the `read_debuginfo` function
and merging it with the main module translation that happens which is
driven by cranelift. Some new hooks were added to the module environment
trait to support this, but most of it was integrating with existing hooks.

* Fix tests in debug crate
2020-08-03 09:59:20 -05:00
Yury Delendik
42127aac4e Refactor Cache logic to include debug information (#2065)
* move caching to the CompilationArtifacts

* mv cache_config from Compiler to CompiledModule

* hash isa flags

* no cache for wasm2obj

* mv caching to wasmtime crate

* account each Compiler field when hash
2020-07-23 12:10:13 -05:00
Yury Delendik
091373f9b8 Removes duplicate code in src/obj.rs, crates/obj and crates/jit/object.rs (#1993)
Changes:

 -  Moves object creation code from crates/jit/object.rs to the creates/obj (as ObjectBuilder)
 -   Removes legacy crates/obj/function.rs
 -  Removes write_debugsections
2020-07-08 12:14:19 -05:00
Nick Fitzgerald
f30ce1fe97 externref: implement stack map-based garbage collection
For host VM code, we use plain reference counting, where cloning increments
the reference count, and dropping decrements it. We can avoid many of the
on-stack increment/decrement operations that typically plague the
performance of reference counting via Rust's ownership and borrowing system.
Moving a `VMExternRef` avoids mutating its reference count, and borrowing it
either avoids the reference count increment or delays it until if/when the
`VMExternRef` is cloned.

When passing a `VMExternRef` into compiled Wasm code, we don't want to do
reference count mutations for every compiled `local.{get,set}`, nor for
every function call. Therefore, we use a variation of **deferred reference
counting**, where we only mutate reference counts when storing
`VMExternRef`s somewhere that outlives the activation: into a global or
table. Simultaneously, we over-approximate the set of `VMExternRef`s that
are inside Wasm function activations. Periodically, we walk the stack at GC
safe points, and use stack map information to precisely identify the set of
`VMExternRef`s inside Wasm activations. Then we take the difference between
this precise set and our over-approximation, and decrement the reference
count for each of the `VMExternRef`s that are in our over-approximation but
not in the precise set. Finally, the over-approximation is replaced with the
precise set.

The `VMExternRefActivationsTable` implements the over-approximized set of
`VMExternRef`s referenced by Wasm activations. Calling a Wasm function and
passing it a `VMExternRef` moves the `VMExternRef` into the table, and the
compiled Wasm function logically "borrows" the `VMExternRef` from the
table. Similarly, `global.get` and `table.get` operations clone the gotten
`VMExternRef` into the `VMExternRefActivationsTable` and then "borrow" the
reference out of the table.

When a `VMExternRef` is returned to host code from a Wasm function, the host
increments the reference count (because the reference is logically
"borrowed" from the `VMExternRefActivationsTable` and the reference count
from the table will be dropped at the next GC).

For more general information on deferred reference counting, see *An
Examination of Deferred Reference Counting and Cycle Detection* by Quinane:
https://openresearch-repository.anu.edu.au/bitstream/1885/42030/2/hon-thesis.pdf

cc #929

Fixes #1804
2020-06-15 09:39:37 -07:00
bjorn3
9788b02dd5 Bump object to 0.19.0 (#1767)
* Bump object to 0.19.0
2020-06-12 15:37:04 -05:00
Alex Crichton
5fa4d36b0d Disable Cranelift debug verifier when fuzzing (#1851)
* Add CLI flags for internal cranelift options

This commit adds two flags to the `wasmtime` CLI:

* `--enable-cranelift-debug-verifier`
* `--enable-cranelift-nan-canonicalization`

These previously weren't exposed from the command line but have been
useful to me at least for reproducing slowdowns found during fuzzing on
the CLI.

* Disable Cranelift debug verifier when fuzzing

This commit disables Cranelift's debug verifier for our fuzz targets.
We've gotten a good number of timeouts on OSS-Fuzz and some I've
recently had some discussion over at google/oss-fuzz#3944 about this
issue and what we can do. The result of that discussion was that there
are two primary ways we can speed up our fuzzers:

* One is independent of Wasmtime, which is to tweak the flags used to
  compile code. The conclusion was that one flag was passed to LLVM
  which significantly increased runtime for very little benefit. This
  has now been disabled in rust-fuzz/cargo-fuzz#229.

* The other way is to reduce the amount of debug checks we run while
  fuzzing wasmtime itself. To put this in perspective, a test case which
  took ~100ms to instantiate was taking 50 *seconds* to instantiate in
  the fuzz target. This 500x slowdown was caused by a ton of
  multiplicative factors, but two major contributors were NaN
  canonicalization and cranelift's debug verifier. I suspect the NaN
  canonicalization itself isn't too pricy but when paired with the debug
  verifier in float-heavy code it can create lots of IR to verify.

This commit is specifically tackling this second point in an attempt to
avoid slowing down our fuzzers too much. The intent here is that we'll
disable the cranelift debug verifier for now but leave all other checks
enabled. If the debug verifier gets a speed boost we can try re-enabling
it, but otherwise it seems like for now it's otherwise not catching any
bugs and creating lots of noise about timeouts that aren't relevant.

It's not great that we have to turn off internal checks since that's
what fuzzing is supposed to trigger, but given the timeout on OSS-Fuzz
and the multiplicative effects of all the slowdowns we have when
fuzzing, I'm not sure we can afford the massive slowdown of the debug verifier.
2020-06-10 12:50:21 -05:00
Yury Delendik
e5b81bbc28 Migrating code to object (from faerie) (#1848)
* Using the "object" library everywhere in wasmtime.
* scroll_derive
2020-06-10 11:27:00 -05:00
Benjamin Bouvier
5d5b39d685 Allow setting other Cranelift flags when running in Wasmtime. 2020-06-10 17:50:25 +02:00
Yury Delendik
4ebbcb82a9 Refactor CompiledModule to separate compile and linking stages (#1831)
* Refactor how relocs are stored and handled

* refactor CompiledModule::instantiate and link_module

* Refactor DWARF creation: split generation and serialization

* Separate DWARF data transform from instantiation

* rm LinkContext
2020-06-09 15:09:48 -05:00
Yury Delendik
15c68f2cc1 Disconnects Store state fields from Compiler (#1761)
*  Moves CodeMemory, VMInterrupts and SignatureRegistry from Compiler
*  CompiledModule holds CodeMemory and GdbJitImageRegistration
*  Store keeps track of its JIT code
*  Makes "jit_int.rs" stuff Send+Sync
*  Adds the threads example.
2020-06-02 13:44:39 -05:00
Dan Gohman
ce757f12d1 Linker refactoring (#1773)
* Minor code tidying.

* Document that `Linker::iter`'s iteration order is arbitrary.

* Add a few more tests for `wasmtime::Linker`.

* Refactor `Linker::compute_imports`.

 - Extract the error message generation into a separate function.
 - In the error message, sort the candidates.

* Fix a typo in a comment.

* Add `__rtti_base` to the list of allowed but deprecated exports.

* Don't print an Error message when a program exits normally.

* Update comments to reflect the current code.

* Also allow "table" as an exported table, which is used by AssemblyScript.
2020-05-28 13:28:05 -07:00
Dan Gohman
3715e19c67 Reactor support. (#1565)
* Reactor support.

This implements the new WASI ABI described here:

https://github.com/WebAssembly/WASI/blob/master/design/application-abi.md

It adds APIs to `Instance` and `Linker` with support for running
WASI programs, and also simplifies the process of instantiating
WASI API modules.

This currently only includes Rust API support.

* Add comments and fix a typo in a comment.

* Fix a rustdoc warning.

* Tidy an unneeded `mut`.

* Factor out instance initialization with `NewInstance`.

This also separates instantiation from initialization in a manner
similar to https://github.com/bytecodealliance/lucet/pull/506.

* Update fuzzing oracles for the API changes.

* Remove `wasi_linker` and clarify that Commands/Reactors aren't connected to WASI.

* Move Command/Reactor semantics into the Linker.

* C API support.

* Fix fuzzer build.

* Update usage syntax from "::" to "=".

* Remove `NewInstance` and `start()`.

* Elaborate on Commands and Reactors and add a spec link.

* Add more comments.

* Fix wat syntax.

* Fix wat.

* Use the `Debug` formatter to format an anyhow::Error.

* Fix wat.
2020-05-26 10:39:40 -05:00
Nick Fitzgerald
f28b3738ee Rename anyref to externref across the board 2020-05-20 11:58:55 -07:00
Dan Gohman
fb0b9e3ae6 Change proc_exit to unwind the stack rather than exiting the host process. (#1646)
* Remove Cranelift's OutOfBounds trap, which is no longer used.

* Change proc_exit to unwind instead of exit the host process.

This implements the semantics in https://github.com/WebAssembly/WASI/pull/235.

Fixes #783.
Fixes #993.

* Fix exit-status tests on Windows.

* Revert the wiggle changes and re-introduce the wasi-common implementations.

* Move `wasi_proc_exit` into the wasmtime-wasi crate.

* Revert the spec_testsuite change.

* Remove the old proc_exit implementations.

* Make `TrapReason` an implementation detail.

* Allow exit status 2 on Windows too.

* Fix a documentation link.

* Really fix a documentation link.
2020-05-13 15:59:43 -07:00
Alex Crichton
57fb1c69c5 Enable the multi-value proposal by default (#1667)
This was merged into the wasm spec upstream in WebAssembly/spec#1145, so
let's follow the spec and enable it by default here as well!
2020-05-06 12:37:29 -05:00
Alex Crichton
363cd2d20f Expose memory-related options in Config (#1513)
* Expose memory-related options in `Config`

This commit was initially motivated by looking more into #1501, but it
ended up balooning a bit after finding a few issues. The high-level
items in this commit are:

* New configuration options via `wasmtime::Config` are exposed to
  configure the tunable limits of how memories are allocated and such.
* The `MemoryCreator` trait has been updated to accurately reflect the
  required allocation characteristics that JIT code expects.
* A bug has been fixed in the cranelift wasm code generation where if no
  guard page was present bounds checks weren't accurately performed.

The new `Config` methods allow tuning the memory allocation
characteristics of wasmtime. Currently 64-bit platforms will reserve 6GB
chunks of memory for each linear memory, but by tweaking various config
options you can change how this is allocate, perhaps at the cost of
slower JIT code since it needs more bounds checks. The methods are
intended to be pretty thoroughly documented as to the effect they have
on the JIT code and what values you may wish to select. These new
methods have been added to the spectest fuzzer to ensure that various
configuration values for these methods don't affect correctness.

The `MemoryCreator` trait previously only allocated memories with a
`MemoryType`, but this didn't actually reflect the guarantees that JIT
code expected. JIT code is generated with an assumption about the
minimum size of the guard region, as well as whether memory is static or
dynamic (whether the base pointer can be relocated). These properties
must be upheld by custom allocation engines for JIT code to perform
correctly, so extra parameters have been added to
`MemoryCreator::new_memory` to reflect this.

Finally the fuzzing with `Config` turned up an issue where if no guard
pages present the wasm code wouldn't correctly bounds-check memory
accesses. The issue here was that with a guard page we only need to
bounds-check the first byte of access, but without a guard page we need
to bounds-check the last byte of access. This meant that the code
generation needed to account for the size of the memory operation
(load/store) and use this as the offset-to-check in the no-guard-page
scenario. I've attempted to make the various comments in cranelift a bit
more exhaustive too to hopefully make it a bit clearer for future
readers!

Closes #1501

* Review comments

* Update a comment
2020-04-29 17:10:00 -07:00
Alex Crichton
c9a0ba81a0 Implement interrupting wasm code, reimplement stack overflow (#1490)
* Implement interrupting wasm code, reimplement stack overflow

This commit is a relatively large change for wasmtime with two main
goals:

* Primarily this enables interrupting executing wasm code with a trap,
  preventing infinite loops in wasm code. Note that resumption of the
  wasm code is not a goal of this commit.

* Additionally this commit reimplements how we handle stack overflow to
  ensure that host functions always have a reasonable amount of stack to
  run on. This fixes an issue where we might longjmp out of a host
  function, skipping destructors.

Lots of various odds and ends end up falling out in this commit once the
two goals above were implemented. The strategy for implementing this was
also lifted from Spidermonkey and existing functionality inside of
Cranelift. I've tried to write up thorough documentation of how this all
works in `crates/environ/src/cranelift.rs` where gnarly-ish bits are.

A brief summary of how this works is that each function and each loop
header now checks to see if they're interrupted. Interrupts and the
stack overflow check are actually folded into one now, where function
headers check to see if they've run out of stack and the sentinel value
used to indicate an interrupt, checked in loop headers, tricks functions
into thinking they're out of stack. An interrupt is basically just
writing a value to a location which is read by JIT code.

When interrupts are delivered and what triggers them has been left up to
embedders of the `wasmtime` crate. The `wasmtime::Store` type has a
method to acquire an `InterruptHandle`, where `InterruptHandle` is a
`Send` and `Sync` type which can travel to other threads (or perhaps
even a signal handler) to get notified from. It's intended that this
provides a good degree of flexibility when interrupting wasm code. Note
though that this does have a large caveat where interrupts don't work
when you're interrupting host code, so if you've got a host import
blocking for a long time an interrupt won't actually be received until
the wasm starts running again.

Some fallout included from this change is:

* Unix signal handlers are no longer registered with `SA_ONSTACK`.
  Instead they run on the native stack the thread was already using.
  This is possible since stack overflow isn't handled by hitting the
  guard page, but rather it's explicitly checked for in wasm now. Native
  stack overflow will continue to abort the process as usual.

* Unix sigaltstack management is now no longer necessary since we don't
  use it any more.

* Windows no longer has any need to reset guard pages since we no longer
  try to recover from faults on guard pages.

* On all targets probestack intrinsics are disabled since we use a
  different mechanism for catching stack overflow.

* The C API has been updated with interrupts handles. An example has
  also been added which shows off how to interrupt a module.

Closes #139
Closes #860
Closes #900

* Update comment about magical interrupt value

* Store stack limit as a global value, not a closure

* Run rustfmt

* Handle review comments

* Add a comment about SA_ONSTACK

* Use `usize` for type of `INTERRUPTED`

* Parse human-readable durations

* Bring back sigaltstack handling

Allows libstd to print out stack overflow on failure still.

* Add parsing and emission of stack limit-via-preamble

* Fix new example for new apis

* Fix host segfault test in release mode

* Fix new doc example
2020-04-21 11:03:28 -07:00
Dan Gohman
9364eb1d98 Refactor (#1524)
* Compute instance exports on demand.

Instead having instances eagerly compute a Vec of Externs, and bumping
the refcount for each Extern, compute Externs on demand.

This also enables `Instance::get_export` to avoid doing a linear search.

This also means that the closure returned by `get0` and friends now
holds an `InstanceHandle` to dynamically hold the instance live rather
than being scoped to a lifetime.

* Compute module imports and exports on demand too.

And compute Extern::ty on demand too.

* Add a utility function for computing an ExternType.

* Add a utility function for looking up a function's signature.

* Add a utility function for computing the ValType of a Global.

* Rename wasmtime_environ::Export to EntityIndex.

This helps differentiate it from other Export types in the tree, and
describes what it is.

* Fix a typo in a comment.

* Simplify module imports and exports.

* Make `Instance::exports` return the export names.

This significantly simplifies the public API, as it's relatively common
to need the names, and this avoids the need to do a zip with
`Module::exports`.

This also changes `ImportType` and `ExportType` to have public members
instead of private members and accessors, as I find that simplifies the
usage particularly in cases where there are temporary instances.

* Remove `Instance::module`.

This doesn't quite remove `Instance`'s `module` member, it gets a step
closer.

* Use a InstanceHandle utility function.

* Don't consume self in the `Func::get*` methods.

Instead, just create a closure containing the instance handle and the
export for them to call.

* Use `ExactSizeIterator` to avoid needing separate `num_*` methods.

* Rename `Extern::func()` etc. to `into_func()` etc.

* Revise examples to avoid using `nth`.

* Add convenience methods to instance for getting specific extern types.

* Use the convenience functions in more tests and examples.

* Avoid cloning strings for `ImportType` and `ExportType`.

* Remove more obviated clone() calls.

* Simplify `Func`'s closure state.

* Make wasmtime::Export's fields private.

This makes them more consistent with ExportType.

* Fix compilation error.

* Make a lifetime parameter explicit, and use better lifetime names.

Instead of 'me, use 'instance and 'module to make it clear what the
lifetime is.

* More lifetime cleanups.
2020-04-20 15:55:33 -05:00
Peter Huene
f7e9f86ba9 Refactor unwind generation in Cranelift.
This commit makes the following changes to unwind information generation in
Cranelift:

* Remove frame layout change implementation in favor of processing the prologue
  and epilogue instructions when unwind information is requested.  This also
  means this work is no longer performed for Windows, which didn't utilize it.
  It also helps simplify the prologue and epilogue generation code.

* Remove the unwind sink implementation that required each unwind information
  to be represented in final form. For FDEs, this meant writing a
  complete frame table per function, which wastes 20 bytes or so for each
  function with duplicate CIEs.  This also enables Cranelift users to collect the
  unwind information and write it as a single frame table.

* For System V calling convention, the unwind information is no longer stored
  in code memory (it's only a requirement for Windows ABI to do so).  This allows
  for more compact code memory for modules with a lot of functions.

* Deletes some duplicate code relating to frame table generation.  Users can
  now simply use gimli to create a frame table from each function's unwind
  information.

Fixes #1181.
2020-04-16 11:15:32 -07:00
Alex Crichton
c4e90f729c wasmtime: Pass around more contexts instead of fields (#1486)
* wasmtime: Pass around more contexts instead of fields

This commit refactors some wasmtime internals to pass around more
context-style structures rather than individual fields of each
structure. The intention here is to make the addition of fields to a
structure easier to plumb throughout the internals of wasmtime.
Currently you need to edit lots of functions to pass lots of parameters,
but ideally after this you'll only need to edit one or two struct fields
and then relevant locations have access to the information already.

Updates in this commit are:

* `debug_info` configuration is now folded into `Tunables`. Additionally
  a `wasmtime::Config` now holds a `Tunables` directly and is passed
  into an internal `Compiler`. Eventually this should allow for direct
  configuration of the `Tunables` attributes from the `wasmtime` API,
  but no new configuration is exposed at this time.

* `ModuleTranslation` is now passed around as a whole rather than
  passing individual components to allow access to all the fields,
  including `Tunables`.

This was motivated by investigating what it would take to optionally
allow loops and such to get interrupted, but that sort of codegen
setting was currently relatively difficult to plumb all the way through
and now it's hoped to be largely just an addition to `Tunables`.

* Fix lightbeam compile
2020-04-08 19:02:49 -05:00
Johnnie Birch
dff789c7c6 Adds JIT profiling support for VTune (#819)
This patch adds initial support for ittapi which is an open
source profiling api for instrumentation and tracing and profiling
of jitted code. Result files can be read by VTune for analysis

Build:
    cargo build --features=vtune
Profile: // Using amplxe-cl from VTune
    amplxe-cl -v -collect hostpost target/debug/wasmtime --vtune test.wasm
2020-04-02 09:04:08 -05:00
Peter Huene
0d5d63fdb1 Support WASI snapshot0 in the C API.
This commit adds support for snapshot0 in the WASI C API.

A name parameter was added to `wasi_instance_new` to accept which WASI module
is being instantiated.

Additionally, the C# API now supports constructing a WASI instance based on the
WASI module name.

Fixes #1221.
2020-03-25 18:22:22 -07:00
Dan Gohman
a7d84afeb4 Remove the old wast and wasm2obj commands. (#1372)
* Remove the old wast and wasm2obj commands.

These are subsumed by the `wasmtime wast` and `wasmtime wasm2obj` commands.

Fixes #827.

* Remove wasm2obj install commands.
2020-03-20 16:30:37 -07:00
Alex Crichton
3b7cb6ee64 Enable jitdump profiling support by default (#1310)
* Enable jitdump profiling support by default

This the result of some of the investigation I was doing for #1017. I've
done a number of refactorings here which culminated in a number of
changes that all amount to what I think should result in jitdump support being
enabled by default:

* Pass in a list of finished functions instead of just a range to
  ensure that we're emitting jit dump data for a specific module rather
  than a whole `CodeMemory` which may have other modules.
* Define `ProfilingStrategy` in the `wasmtime` crate to have everything
  locally-defined
* Add support to the C API to enable profiling
* Documentation added for profiling with jitdump to the book
* Split out supported/unsupported files in `jitdump.rs` to avoid having
  lots of `#[cfg]`.
* Make dependencies optional that are only used for `jitdump`.
* Move initialization up-front to `JitDumpAgent::new()` instead of
  deferring it to the first module.
* Pass around `Arc<dyn ProfilingAgent>` instead of
  `Option<Arc<Mutex<Box<dyn ProfilingAgent>>>>`

The `jitdump` Cargo feature is now enabled by default which means that
our published binaries, C API artifacts, and crates will support
profiling at runtime by default. The support I don't think is fully
fleshed out and working but I think it's probably in a good enough spot
we can get users playing around with it!
2020-03-20 11:44:51 -05:00
Alex Crichton
34f768ddd5 Temporarily remove support for interface types (#1292)
* Temporarily remove support for interface types

This commit temporarily removes support for interface types from the
`wasmtime` CLI and removes the `wasmtime-interface-types` crate. An
error is now printed for any input wasm modules that have wasm interface
types sections to indicate that support has been removed and references
to two issues are printed as well:

* #677 - tracking work for re-adding interface types support
* #1271 - rationale for removal and links to other discussions

Closes #1271

* Update the python extension
2020-03-12 15:05:39 -05:00
Dan Gohman
d44384da8a Exit with a more severe error code if the program traps. (#1274)
* Exit with a more severe error code if the program traps.

Previously, the wasmtime CLI would return with a regular failure
error code, such as 1 on Unix. However, a program trap indicates a bug
in the program, which can be useful to distinguish from a simple error
status. Check for the trap case, and return an appropriate OS-specific
exit status.

* Use a loop to iterate over the error causes to find Traps.

* Use anyhow's `chain()` iterator.

* For completeness, handle non-Unix and non-Windows platforms too.

* Add a CLI test for a trapping program.

* Replace a manual `.cause` loop with a `.is` call.

* Correct the expected exit status on Windows.

* Use assert_eq/assert_ne so that if these fail, it prints the output.
2020-03-11 13:12:26 -07:00
Yury Delendik
f76b36f737 Write .debug_frame information (#53)
* Write .debug_frame information

* mv map_reg
2020-03-11 10:22:51 -05:00
Dan Gohman
ac0ee271b1 Log to stderr by default. (#1266)
Change the default from file-per-thread-logger to pretty-env-logger,
which is more common in Rust projects, and change the option from `-d`
to `--log-to-files`.
2020-03-10 09:36:56 -05:00
Yury Delendik
ba1f10f4d4 Removes panic! from the debug crate. (#1261) 2020-03-09 12:25:38 -05:00
Andrew Brown
1d15054310 Remove the debug crate's hard-coded dependency on register ordering 2020-03-06 10:53:22 -08:00
Alex Crichton
c8ab1e293e Improve robustness of cache loading/storing (#974)
* Improve robustness of cache loading/storing

Today wasmtime incorrectly loads compiled compiled modules from the
global cache when toggling settings such as optimizations. For example
if you execute `wasmtime foo.wasm` that will cache globally an
unoptimized version of the wasm module. If you then execute `wasmtime -O
foo.wasm` it would then reload the unoptimized version from cache, not
realizing the compilation settings were different, and use that instead.
This can lead to very surprising behavior naturally!

This commit updates how the cache is managed in an attempt to make it
much more robust against these sorts of issues. This takes a leaf out of
rustc's playbook and models the cache with a function that looks like:

    fn load<T: Hash>(
        &self,
        data: T,
        compute: fn(T) -> CacheEntry,
    ) -> CacheEntry;

The goal here is that it guarantees that all the `data` necessary to
`compute` the result of the cache entry is hashable and stored into the
hash key entry. This was previously open-coded and manually managed
where items were hashed explicitly, but this construction guarantees
that everything reasonable `compute` could use to compile the module is
stored in `data`, which is itself hashable.

This refactoring then resulted in a few workarounds and a few fixes,
including the original issue:

* The `Module` type was split into `Module` and `ModuleLocal` where only
  the latter is hashed. The previous hash function for a `Module` left
  out items like the `start_func` and didn't hash items like the imports
  of the module. Omitting the `start_func` was fine since compilation
  didn't actually use it, but omitting imports seemed uncomfortable
  because while compilation didn't use the import values it did use the
  *number* of imports, which seems like it should then be put into the
  cache key. The `ModuleLocal` type now derives `Hash` to guarantee that
  all of its contents affect the hash key.

* The `ModuleTranslationState` from `cranelift-wasm` doesn't implement
  `Hash` which means that we have a manual wrapper to work around that.
  This will be fixed with an upstream implementation, since this state
  affects the generated wasm code. Currently this is just a map of
  signatures, which is present in `Module` anyway, so we should be good
  for the time being.

* Hashing `dyn TargetIsa` was also added, where previously it was not
  fully hashed. Previously only the target name was used as part of the
  cache key, but crucially the flags of compilation were omitted (for
  example the optimization flags). Unfortunately the trait object itself
  is not hashable so we still have to manually write a wrapper to hash
  it, but we likely want to add upstream some utilities to hash isa
  objects into cranelift itself. For now though we can continue to add
  hashed fields as necessary.

Overall the goal here was to use the compiler to expose what we're not
hashing, and then make sure we organize data and write the right code to
ensure everything is hashed, and nothing more.

* Update crates/environ/src/module.rs

Co-Authored-By: Peter Huene <peterhuene@protonmail.com>

* Fix lightbeam

* Fix compilation of tests

* Update the expected structure of the cache

* Revert "Update the expected structure of the cache"

This reverts commit 2b53fee426a4e411c313d8c1e424841ba304a9cd.

* Separate the cache dir a bit

* Add a test the cache is busted with opt levels

* rustfmt

Co-authored-by: Peter Huene <peterhuene@protonmail.com>
2020-02-26 16:18:02 -06:00
Peter Huene
fa65a14dba Make WasiCtxBuilder by-ref.
This commit makes `WasiCtxBuilder` take `&mut Self` and return `&mut
Self` for its methods.  This is needed to allow for the same
(unmoved) `WasiCtxBuilder` to be used when building a WASI context.

Also fixes up the C API to remove the unnecessary `Box::from_raw` and
`forget` calls which were previously needed for the moving version of
`WasiCtxBuilder`.
2020-02-25 15:41:18 -08:00
Alex Crichton
d4fcd32cdc Optimize generated code via the CLI by default (#973)
* Optimize generated code via the CLI by default

This commit updates the behavior of the CLI and adds a new flag. It
first enables the `--optimize` flag by default, ensuring that usage of
the `wasmtime` CLI will enable cranelift optimizations by default. Next
it also adds a `--opt-level` flag which is similar to Rust's
`-Copt-level` where it takes a string argument of how to optimize. This
is updates to support 0/1/2/s, where 1 is currently the same as 2 but
added for consistency with other compilers. The default setting is
`--opt-level=2`.

When the `-O` flag is not passed the `--opt-level` flag is used,
otherwise `-O` takes precedent in the sense that it implies
`--opt-level=2` which is the highest optimization level. The thinking is
that these flags will in general select the highest optimization level
specified as the final optimization level.

* Add inline docs

* fix a test
2020-02-24 15:18:08 -06:00
Johnnie Birch
9c6150b103 Adds perf jitdump support (#360)
Patch adds support for the perf jitdump file specification.
With this patch it should be possible to see profile data for code
generated and maped at runtime. Specifically the patch adds support
for the JIT_CODE_LOAD and the JIT_DEBUG_INFO record as described in
the specification. Dumping jitfiles is enabled with the --jitdump
flag. When the -g flag is also used there is an attempt to dump file
and line number information where this option would be most useful
when the WASM file already includes DWARF debug information.

The generation of the jitdump files has been tested on only a few wasm
files. This patch is expected to be useful/serviceable where currently
there is no means for jit profiling, but future patches may benefit
line mapping and add support for additional jitdump record types.

Usage Example:
Record
  sudo perf record -k 1 -e instructions:u target/debug/wasmtime -g
  --jitdump test.wasm
Combine
  sudo perf inject -v -j -i perf.data -o perf.jit.data
Report
  sudo perf report -i perf.jit.data -F+period,srcline
2020-02-21 08:30:21 -06:00
Yury Delendik
b96b53eafb Test basic DWARF generation (#931)
* Add obj generation with debug info
* Add simple transform check
2020-02-20 11:42:36 -06:00
Alex Crichton
a6adf52429 Add more CLI flags for wasm features (#917)
* Add more CLI flags for wasm features

This commit adds a few more flags to enable wasm features via the CLI,
mirroring the existing `--enable-simd` flag:

* `--enable-reference-types`
* `--enable-multi-value`
* `--enable-threads`
* `--enable-bulk-memory`

Additionally the bulk memory feature is now automatically enabled if
`reference-types` or `threads` are enabled since those two proposals
largely depend on `bulk-memory`.

* Add --enable-all to enable all wasm features

* Update src/lib.rs

Co-Authored-By: Peter Huene <peterhuene@protonmail.com>

* Apply suggestions from code review

Co-Authored-By: Peter Huene <peterhuene@protonmail.com>

Co-authored-by: Peter Huene <peterhuene@protonmail.com>
2020-02-07 04:06:59 -06:00
Alex Crichton
70345aff31 Remove all global state from the caching system (#863)
* Remove all global state from the caching system

This commit is a continuation of an effort to remove usages of
`lazy_static!` and similar global state macros which can otherwise be
accomodated with passing objects around. Previously there was a global
cache system initialized per-process, but it was initialized in a bit of
a roundabout way and wasn't actually reachable from the `wasmtime` crate
itself. The changes here remove all global state, refactor many of the
internals in the cache system, and makes configuration possible through
the `wasmtime` crate.

Specifically some changes here are:

* Usage of `lazy_static!` and many `static` items in the cache module
  have all been removed.
* Global `cache_config()`, `worker()`, and `init()` functions have all
  been removed. Instead a `CacheConfig` is a "root object" which
  internally owns its worker and passing around the `CacheConfig` is
  required for cache usage.
* The `wasmtime::Config` structure has grown options to load and parse
  cache files at runtime. Currently only loading files is supported,
  although we can likely eventually support programmatically configuring
  APIs as well.
* Usage of the `spin` crate has been removed and the dependency is removed.
* The internal `errors` field of `CacheConfig` is removed, instead
  changing all relevant methods to return a `Result<()>` instead of
  storing errors internally.
* Tests have all been updated with the new interfaces and APIs.

Functionally no real change is intended here. Usage of the `wasmtime`
CLI, for example, should still enable the cache by default.

* Fix lightbeam compilation
2020-02-06 13:11:06 -06:00
Alex Crichton
3dd5a3cb3f Reimplement wasmtime-wasi on top of wasmtime (#899)
* Reimplement `wasmtime-wasi` on top of `wasmtime`

This commit reimplements the `wasmtime-wasi` crate on top of the
`wasmtime` API crate, instead of being placed on top of the `wasmtime-*`
family of internal crates. The purpose here is to continue to exercise
the API as well as avoid usage of internals wherever possible and
instead use the safe API as much as possible.

The `wasmtime-wasi` crate's API has been updated as part of this PR as
well. The general outline of it is now:

* Each module snapshot has a `WasiCtxBuilder`, `WasiCtx`, and `Wasi`
  type.
  * The `WasiCtx*` types are reexported from `wasi-common`.
  * The `Wasi` type is synthesized by the `wig` crate's procedural macro
* The `Wasi` type exposes one constructor which takes a `Store` and a
  `WasiCtx`, and produces a `Wasi`
* Each `Wasi` struct fields for all the exported functions in that wasi
  module. They're all public an they all have type `wasmtime::Func`
* The `Wasi` type has a `get_export` method to fetch an struct field by
  name.

The intention here is that we can continue to make progress on #727 by
integrating WASI construction into the `Instance::new` experience, but
it requires everything to be part of the same system!

The main oddity required by the `wasmtime-wasi` crate is that it needs
access to the caller's `memory` export, if any. This is currently done
with a bit of a hack and is expected to go away once interface types are
more fully baked in.

* Remove now no-longer-necessary APIs from `wasmtime`

* rustfmt

* Rename to from_abi
2020-02-06 09:23:06 -06:00
Yury Delendik
4599234c6f Don't generate DWARF sections when no functions were compiled. (#894) 2020-02-03 14:41:29 -06:00
Sergei Pepyakin
eb183d7ab3 Run rustfmt 1.41 (#877) 2020-01-30 21:03:50 +01:00
Alex Crichton
21e0a99884 Delete the wasmtime-wasi-c crate (#844)
This commit deletes the old C implementation of the original
`wasi_unstable` module, instead only leaving around our single
`wasmtime-wasi` crate as the implementation for both
`wasi_snapshot_preview1` and `wasi_unstable`.

This hasn't been discussed (AFAIK) up until now, so this is also a
proposal! Some thoughts in favor of this deletion I would have are:

* This has been off-by-default for ages
* We don't build or test any of this on CI
* Published binaries with `wasmtime` do not have this possibility
  enabled
* Future refactorings to the `wasmtime-wasi` crate will either need to
  work around how the C implementation is different or bring it up to
  speed.

This is motivated by the last bullet point where I was working on
getting `wasmtime-wasi` working purely as an implementation detail on
top of the `wasmtime` crate itself, but quickly ran into a case where
the CLI would need to multiplex all sorts of wasi implementations. In
any case I'm curious what others think, is this too soon? Is there
something remaining blocking this? (etc)
2020-01-24 08:54:17 -08:00