Instead of using MOVUPS to expensively load bits from memory, this change uses a predicate to optimize vconst without a memory access:
- when the 128-bit immediate is all zeroes in all bits, use PXOR to zero out an XMM register
- when the 128-bit immediate is all ones in all bits, use PCMPEQB to set an XMM register to all ones
This leaves the constant data in the constant pool, which may increase code size (TODO)
- `fill` attempted to use a GPR recipe, `fillSib32`, instead of its FPR equivalent, `ffillSib32` (code compiled without error but incorrect instructions were allowed, e.g. `v1 = regmove v0, %rdi -> %xmm0`
- `regmove` could be encoded with a GPR recipe, `rmov`, which hid the above incorrectness; now only FPR-to-FPR regmoves are allowed using the `frmov` recipe
This patch:
* removes the "default" opt level, on the basis that it has no definition and
is referred to nowhere in the compiler.
* renames the "fastest" level to "none". The resulting set of transformations
is unchanged.
* renames the "best" level to "speed_and_size". The resulting set of
transformations is unchanged.
* adds a new level, "speed". This is the same as "speed_and_size" except that
it omits transformations aimed only at reducing code size. Currently it
omits only the insn shrinking pass.
Enables automated fuzzing on Fuzzit. Runs fuzz regression tests
every push and PR. Runs full fuzzing every push. Fuzzit emails
if it finds crashes.
Uses the existing fuzz targets:
* translate-module - Fuzz valid WebAssembly modules.
* reader-parse - Fuzz IR text format parsing.
Enables automated fuzzing on Fuzzit. Runs fuzz regression tests
every push and PR. Runs full fuzzing every push. Fuzzit emails
if it finds crashes.
Uses the existing fuzz targets:
* translate-module - Fuzz valid WebAssembly modules.
* reader-parse - Fuzz IR text format parsing.
* Mark public API functions as unsafe.
This marks the public hostcalls functions as unsafe.
This is generalizing from Rust's `from_raw_fd` function, which is
unsafe. The observation is that nothing prevents code using this
function from passing a bogus or stale dangling file descriptor and
corrupting an arbitrary open stream.
Technically, some of these functions don't use file descriptors, such as
random, clocks, and a few others. However I expect that in the future,
random and clocks will switch to using file descriptors anyway, and it
keeps the macro definitions simpler if we only have to handle one form.
* Mark WasiCtx functions that operate on file descriptors unsafe too.
* `fd_filestat_set_times_impl` doesn't need to be unsafe.
* Remove unnecessary unsafes
