slightly worse for compile time, slightly better output, honestly I'll take the
win because this is easier to reason about.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
I don't get the point, it should be handled by a combination of existing
passes/techniques just fine. no instcountci changes.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
No reason to have a separate pass for this, merging should be a bit faster since
it eliminates an IR walk.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
find-and-replace across the tree, excluding IR.h itself.
also excluded IRValidation because its treatment of blocks blows up and will be
reformed in the new IR anyway.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
deduplicate all the things.
functional change:
hit by sse4_1-pmaxuw.c.gcc-target-test-64.jit.gcc-target-64
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
This was causing us to generate invalid code in Darwinia, resulting in a
crash. With assertions enabled this would be picked up in the emitter.
Only implement AddShift optimizations for now because I don't want to do
the remaining optimizations in a bug fix PR.
Fixes Darwinia.
Accidentally we were swapping which sources were the base and which was
the one getting shifted. This wasn't super common so it usually didn't
matter.
Fixes one crash in Darwinia.
use a vec. block indices will be dense in the new IR. This is memory intensive
but seems faster in practice.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Flag DCE needs to do general DCE anyway to converge in one pass. So we can move
the special syscall/atomic logic over to flag DCE and then drop the second DCE
pass altogether. Now local dead code of both is eliminated in a single pass.
Flag DCE is carefully written to converge in a single iteration which makes this
scheme work.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
If both the destination and the flags are dead for an AddWithFlags, we need to
eliminate it in one pass. If we only replace without elimiating, we would need a
second DCE pass to eliminate. We want DCE to finish in one pass, so fix this.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
This has been deadcode since 2020. Drop it so we can focus on what *does* work
and what does matter.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Generally, there are three reasons to track progress:
* Conditional optimizations. E.g. only run DCE if ConstProp succeeds.
* Fixed point optimizations. E.g. keep running the opt loop until convergence.
* Metadata shenianigans.
None of these apply to FEX. We explicitly do not want a nonlinear pass ordering,
instead we want just a few passes that each converge in a single iteration. We
expect them all to make progress when run. As such, tracking progress is a waste
of CPU cycles. Stop doing it.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
New RA does not need it for correctness, and the slight slow down to new RA from
not compacting first is much smaller than the cost of compaction. Overall speeds
up node.js start time by ~6% on top of new RA.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>