Similar to the previous far jmp, if the CS changes operating mode then
things will still explode with other FEX asserts. But this gets another
change out of my stashes.
These instructions go hand-in-hand obviously so they get implemented as
a pair.
Taking this very slowly because this is very fickle code. The frontend
needs to manage GDT and LDT, but before we get there, we need to
actually add support for LDT in the backend. Split the segments to two
arrays so the JIT can actually update their cached values correctly.
Still treats GDT and LDT as mirrors like how the JIT previously did (By
it ignoring the selector's TI bit).
Hashmaps are super expensive and there's no reason not to use a vector - we
already have compact block IDs so we don't benefit from the sparseness. Huge win
for very little effort.
Spotted when profiling FEX. CondJump() in the JIT was almost 4% of our time (?!)
and all because of map slowness. Easy fix.
Difference at 95.0% confidence
-0.0196494 +/- 0.00194956
-3.92827% +/- 0.389753%
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
..and be consistent about signedness.
clang doesn't seem able to do this itself.
Difference at 95.0% confidence, n=100
-0.272326% +/- 0.242353%
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
now obsolete!
Results for the whole series are excellent:
Difference at 95.0% confidence
-3.97603% +/- 0.254656%
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Augment IREmitter to inline constants as we generate code, rather than
needing a later clean up pass. This replaces the last function of ConstProp.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Now executable page tracking is implemented, this limit is technically
unnecessary and effectively never hit in normal code. Keep a reasonable
limit however to avoid accidentally inlining tail calls and exploring
dead branches in obfuscated code.
In b8dd5d95b ("OpcodeDispatcher: optimize X87FTWTag"), we optimized
X87FTWTag using an efficient Morton interleave operation. Here, we do the
inverse, optimizing SetX87FTW using an efficient Morton deinterleave
operation.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
I don't think these are worth it, and also currently they don't trigger ever.
n=100:
Difference at 95.0% confidence
-0.00245961 +/- 0.00139573
-0.524468% +/- 0.297615%
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
This is expensive and only needed for spilling, so only do it for spilling. This
complicates the RA a bit but speeds us up on average since most blocks
don't spill. Total results of this change (including the prep commits that
slowed things down temporarily):
Difference at 95.0% confidence
-1.71952% +/- 0.455996%
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Ryan Houdek