* Consume fuel during function execution
This commit adds codegen infrastructure necessary to instrument wasm
code to consume fuel as it executes. Currently nothing is really done
with the fuel, but that'll come in later commits.
The focus of this commit is to implement the codegen infrastructure
necessary to consume fuel and account for fuel consumed correctly.
* Periodically check remaining fuel in wasm JIT code
This commit enables wasm code to periodically check to see if fuel has
run out. When fuel runs out an intrinsic is called which can do what it
needs to do in the result of fuel running out. For now a trap is thrown
to have at least some semantics in synchronous stores, but another
planned use for this feature is for asynchronous stores to periodically
yield back to the host based on fuel running out.
Checks for remaining fuel happen in the same locations as interrupt
checks, which is to say the start of the function as well as loop
headers.
* Improve codegen by caching `*const VMInterrupts`
The location of the shared interrupt value and fuel value is through a
double-indirection on the vmctx (load through the vmctx and then load
through that pointer). The second pointer in this chain, however, never
changes, so we can alter codegen to account for this and remove some
extraneous load instructions and hopefully reduce some register
pressure even maybe.
* Add tests fuel can abort infinite loops
* More fuzzing with fuel
Use fuel to time out modules in addition to time, using fuzz input to
figure out which.
* Update docs on trapping instructions
* Fix doc links
* Fix a fuzz test
* Change setting fuel to adding fuel
* Fix a doc link
* Squelch some rustdoc warnings
Recent changes to fuzzers made expectations more strict about handling
errors while fuzzing, but this erroneously changed a module compilation
step to always assume that the input wasm is valid. Instead a flag is
now passed through indicating whether the wasm blob is known valid or
invalid, and only if compilation fails and it's known valid do we panic.
This commit uses the new `MaybeInvalidModule` type in `wasm-smith` to
try to explore more points in the fuzz target space in the
`instantiate-maybe-invalid` fuzz target. The goal here is to use the raw
fuzz input as the body of a function to stress the validator/decoder a
bit more, and try to get inputs we might not otherwise generate.
- Properly mask constant values down to appropriate width when
generating a constant value directly in aarch64 backend. This was a
miscompilation introduced in the new-isel refactor. In combination
with failure to respect NarrowValueMode, this resulted in a very
subtle bug when an `i32` constant was used in bit-twiddling logic.
- Add support for `iadd_ifcout` in aarch64 backend as used in explicit
heap-check mode. With this change, we no longer fail heap-related
tests with the huge-heap-region mode disabled.
- Remove a panic that was occurring in some tests that are currently
ignored on aarch64, by simply returning empty/default information in
`value_label` functionality rather than touching unimplemented APIs.
This is not a bugfix per-se, but removes confusing panic messages from
`cargo test` output that might otherwise mislead.
Looks like everything is in general passing now so it's probably time to
close#1521 and all other remaining tests that are failing are
classified under new more focused issues.
Closes#1521
* Add AArch64 tests to CI
This commit enhances our CI with an AArch64 builder. Currently we have
no physical hardware to run on so for now we run all tests in an
emulator. The AArch64 build is cross-compiled from x86_64 from Linux.
Tests all happen in release mode with a recent version of QEMU (recent
version because it's so much faster, and in release mode because debug
mode tests take quite a long time in an emulator).
The goal here was not to get all tests passing on CI, but rather to get
AArch64 running on CI and get it green at the same time. To achieve that
goal many tests are now ignored on aarch64 platforms. Many tests fail
due to unimplemented functionality in the aarch64 backend (#1521), and
all wasmtime tests involving compilation are also disabled due to
panicking attempting to generate generate instruction offset information
for trap symbolication (#1523).
Despite this, though, all Cranelift tests and other wasmtime tests
should be runnin on AArch64 through QEMU with this PR. Additionally
we'll have an AArch64 binary release of Wasmtime for Linux, although it
won't be too useful just yet since it will panic on almost all wasm
modules.
* Review comments
* Move most wasmtime tests into one test suite
This commit moves most wasmtime tests into a single test suite which
gets compiled into one executable instead of having lots of test
executables. The goal here is to reduce disk space on CI, and this
should be achieved by having fewer executables which means fewer copies
of `libwasmtime.rlib` linked across binaries on the system. More
importantly though this means that DWARF debug information should only
be in one executable rather than duplicated across many.
* Share more build caches
Globally set `RUSTFLAGS` to `-Dwarnings` instead of individually so all
build steps share the same value.
* Allow some dead code in cranelift-codegen
Prevents having to fix all warnings for all possible feature
combinations, only the main ones which come up.
* Update some debug file paths
