... at http://www.mirandabanda.org/files/Cog/VM/VM.r3311/.
These should fix the regression introduced by the map changes in
3308. They certainly fix the two crashes I've looked at, one an
update of a squeak trunk image and the other the startup of
recent Newspeak images. Apologies for the inconvenience.
Well, this is embarrassing as usual but I'm still seeing crashes
in the image update. So I'll have to look deeper. At least the
Newspeak fix was real, but it didn't fix everything.
:)
Hi eliot
How can we help?
Would it make sense to have some more ci jobs for testing the VM?
Yes, that always helps. But we have to accept that that means
a) these CI jobs will detect failures caused by regressions etc
b) we need to mark builds as "bleeding edge" "last known good" etc,
and set these pointers
b) I have yet to set up.
But yesterday and today a wonderful thing has happened. Clément has
understood the core optimization and code generation structures in the
JIT as well as I do and is now both improving the code quality and
implementing more aggressive optimizations.
That's cool.
This is /so/ satisfying. You know how good Clément is. His input is
so strong. I am /very/ happy. For example, Clément is currently
modifying #== in the Spur JIT so that the code checks for forwarders
only if #== is false, and that if #== is false and either object is a
forwarder, it/them is/are followed and the #== retried. This should
speed up #== by 50%. It won't make much difference at the macro level
but this is a non-trivial optimization to write and so now we have two
people who really understand the core optimizing JIT and I can now
happily run in front of a bus.
I'm happy too.
BTW Kevin is making progress on the decompiler. So we have young guys
learning around too.
Stef
CogVM binaries as per VMMaker.oscog-eem.1204/r3311
Cogits:
Fix regression in map machinery due to adding
AnnotationExtension scheme.
findMapLocationForMcpc:inMethod: must not be confused by
IsDisplacementX2N
bytes. This is likely the cause of the recent crashes with
r3308 and earlier.
Introduce marryFrameCopiesTemps and use it to
not copy temps in Spur context creation trampolines.
Change initial usage counts to keep more recently jitted methods
around for
longer, and do *not* throw away PICs in
freeOlderMethodsForCompaction, so that
there's a better chance of Sista finding send and branch data
for the tripping
method.
extendedPushBytecode /does/ need a frame.
Don't save the header in a scratch register unless
it is useful to do so in the Spur at:[put:] primitives.
Fix slip in genGetNumBytesOf:into:. And notice that
genGetFormatOf:into:baseHeaderIntoScratch: et al can use byte access
to get at format, as intended in the Spur header design.
Fix unlinking dynamic super sends.
Reduce false positives in access control violation reporting by
marking the
super send we actually use as privileged. Remove unused Newspeak
bytecodes.
Internal:
Fix code generation bug surfaced by inline primitives. On x86
movb N(%reg),%rl
can only store into al, bl, cl & dl, whereas movzbl can store
into any reg. On
ARM move byte also zero-extends. So change definition of
MoveMbrR to always
zero-extend, use movzbl on x86 and remove all the MoveCq: 0 R:
used to zero the
bits of the target of a MoveMb:r:R:. And now that we have
genGetNumSlotsOf:into:, use it.
Fix a slip in genTrinaryInlinePrimitive:, meet constraint that
the target must
be in ReceiverResultReg, and do a better job of register
allocation there-in.
Do dead code elimination for the branch following an inlined
comparison (this
is done in genBinaryInlineComparison:opFalse:destReg: copying
the scheme in
genSpecialSelectorEqualsEquals).
Do register allocation in the right place in
genUnaryInlinePrimitive:.
Fix overflow slot access in genGetNumSlotsOf:into: et al.
Fix several slips in inline primitive generation:
Object>>at:put: needs to
include a store check. Some register allocation code was
wrong. Some results
needed converting to SmallIntegers and recording results as
pushed on the sim
stack.
Change callPrimitiveBytecode to genCallPrimitiveBytecode in the
Cogit.
remove the misnomer genConvertIntegerToSmallIntegerInScratchReg:
Type of AbstractInstruction opcode must be unsigned now that we have
more than 128 opcodes (XCHGRR pushed things over the top).
Lay the groundwork for 32-bit intra-zone jumps and calls on ARM
by introducing
CallFull and JumpFull (and rewrites thereof) that are expected
to span the full
address space, leaving Call/JumpLong to span merely the 16mb
code zone. On x86
CallFull and JumpFull simply default to Call/JumpLong.
Replace bytecode trapIfNotInstanceOf by jumpIfNotInstanceOfOrPop.
Rewrote the JIT logic for traps to be able to write trap
trampolines calls at
the end of the cogMethod.
Refactor the slot store and store check machinery to take an
inFrame: argument
and hence deal with the store check in genInnerPrimitiveAtPut:
on ARM.
Fix limitation with MoveRXbrR; can only do movb from
%al through %dl, so swap with %eax around movb.
Fix mistake with genGetNumBytesOf:into: by refactoring
genGetFormatOf:into:baseHeaderIntoScratch: into
genGetBits:ofFormatByteOf:into:baseHeaderIntoScratch:
and hence fetching and subtracting only odd bits of format.
Correct the in-line primitive SmallInteger comparisons; CmpXR is
confusing ;-)
Fix var op var unsafe byte at:. Result must be converted to
SmallInteger.
Correct the generated Slang for the new register allocation code
by adding a
read-before-written pass to C generation that initializes variables
read-before-written with 0 (the C equivalent of nil).
fix a bug where sometimes register allocation was marking
ReceiverResultReg as
dead whereas it was still alive.
Added some abstraction over register allocation. This is now
used in inline
primitives.
--
best,
Eliot
