Manually encoding and decoding logical immediates is error-prone.
Using ORRI2R and friends lets us avoid doing the work manually,
but in exchange, there is a runtime performance penalty. It's
probably rather small, but still, it would be nice if we could
let the compiler do the work at compile-time. And that's exactly
what this commit does, so now I have no excuse for trying to
manually write logical immediates anymore.
If a branch is unconditional, its target should not be in farcode,
since that defeats the purpose of farcode (putting seldom executed
code in farcode to keep it out of the icache when possible).
Fixes a 58698b8380 regression. (The EXCEPTION_EXTERNAL_INT
immediate being wrong meant that we never took the branch,
masking the problem of the MSR.EE immediate being wrong...)
In cases where we already know that there is an exception,
either because we just checked for it or because we were
the ones that generated the exception to begin with,
we can skip the branch inside WriteExceptionExit.
Unlike most constants we emit in JitArm64, these constants are
*not* inherent to the CPU we're emulating, and can have whatever
values we want. Let's handle them more robustly, in case we
decide to change their values in the future.
Public domain does not have an internationally agreed upon definition,
As such it's generally preferred to use an extremely liberal license,
which can explicitly list the rights granted by the copyright holder.
The CC0 license is the usual choice here.
This "relicensing" is done without hunting down copyright holders, since
it is presumed that their release of this work into the public domain
authorizes us to redistribute this code under any other license of our
choosing.
This code was part of Dolphin's relicensing from v2 to v2+ a while back,
we just never updated these copyright headers. I double-checked that
segher gave us permission to relicense this code to v2+ on 2015-05-16.
SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.
