This avoids a bunch of sharp edges for RA at a small cost when obscure
segment registers are used.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
From a theoretical perspective, we should not need to run RCLSE more than once.
If there are convergence issues with the current implementation, they should be
fixed instead of bandaged around. Fortunately, this has no instcountci changes.
Brings RCLSE cost down from like 12% to 5%.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
IRListView is now purely a view type. Instead, ownership is managed on-demand
by a separate interface (IRStorageBase). Materialization of IRListViews to
owning types is moved to this interface as well.
This also avoids unneeded copies of the data.
doesn't matter for left shifts (we mask off the garbage), or 32-bit shifts, or
shifts where we explicitly sbfe after.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
alternative to #3638. this is theoretically better for side-by-side diffs. in
practice it may make other diffs worse since all the \'s change when part of the
macro change.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Fixed offset x86 code doesn't quite solve the issue, so adjust this
heuristic just to get instcounci to stop flaking.
This code is going to heavily change soon anyway so +50 doesn't change
much.
undefined instructions are expected to return SIGILL, while implemented
instructions that aren't available in CPL-3 are expected to SIGSEGV.
Noticed this while testing out CPU-Z, it installs a kernel module and
does a bunch of `RDMSR` and `OUTS` instructions. Decided to walk through
the rest of the instructions in the `System Instruction Reference`
section.
Turns out there's a bunch of oddities in there that we don't support.
First step is to go through all the explicitl SIGILL and SIGSEGV and
implement a test for them.
Next step will be implementing the remaining operations that are
considered "System" operations but are still available in CPL-3.
This list includes:
- lar
- lgdt
- lsl
- sidt
- sldt
- stac
- clac
- verr
- verw
Arm64ec introduced the InterruptFaultPage which is lower overhead since
instead of ldr+str it just turns in to a single str. We were already
allocating the space, FEXCore and the frontend signal delegator just
needed to be updated to understand the new location.
We can additionally use this in the future if we want to make deferred
async signals INSIDE the JIT only cost a single str as well.
RA should not depend on whether we support AVX, that's a huge layering
violation! and fortunately, it does not.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
