Displaying 11 results from an estimated 11 matches similar to: "Scheduler: modelling long register reservations?"
2017 Jan 09
4
Tweaking the Register Allocator's spill placement
Hello,
My target features some very-high-latency instructions that access an on-chip network (we'll call them FXLV). In one important kernel (snippet below), register allocation needs to spill values resulting from FXLV. The spiller is unaware of FXLV's latency, and thus naively inserts those spills immediately after the FXLV, incurring huge and unnecessary data stalls.
FXLV r10,
2017 Apr 24
3
Debugging UNREACHABLE "Couldn't join subrange" in RegisterCoalescer (out-of-tree backend)
Hello,
I have a minimal testcase which crashes RegisterCoalescer in my out-of-tree target. It only crashes in Debug builds of llc---not in Release builds. Also, interesting to note that the x86 backend lowers this same testcase successfully. I did a quick search of bugs.llvm.org and found no matches.
This implies that the problem is in my backend and/or how my backend interacts with
2011 Jan 29
3
[LLVMdev] Possible CellSPU Bug?
I'm working on enhancing TableGen's type checking and it triggered with
a problem in CellSPU's specification:
XSHWv4i32: (set VECREG:v8i16:$rDest, (sext:v8i16 VECREG:v4i32:$rSrc))
It's complaining that v4i32 is not smaller than v8i16, which is true in
the sense of vector bit size, and true in the sense of vector element
size. To me, a sign extension from i32 to i16 makes no
2011 Jan 31
0
[LLVMdev] Possible CellSPU Bug?
David Greene wrote:
> class XSHWVecInst<ValueType in_vectype, ValueType out_vectype>:
> def v4i32: XSHWVecInst<v4i32, v8i16>;
> Is this pattern as intended, or did I find a real problem?
Looks like a bug to me. xshw (extend signed half-word(16bits) to
word(32bits)) takes a v8i16 and produces a v4i32. This has likely gone
unnoticed as there is only one type of vector
2011 Jan 31
1
[LLVMdev] Possible CellSPU Bug?
Kalle Raiskila <kalle.raiskila at nokia.com> writes:
> Looks like a bug to me. xshw (extend signed half-word(16bits) to
> word(32bits)) takes a v8i16 and produces a v4i32. This has likely gone
> unnoticed as there is only one type of vector register class (i.e.
> VECREG) that is used for all vectors.
>
> Nice catch :) Are there more of these?
I don't know. I stopped
2015 Oct 15
3
what can cause a "CPU table is not sorted" assertion
I'm trying to create a simplified 2 slot VLIW from an OR1K. The codebase
I'm working with is here <https://github.com/openrisc/llvm-or1k>. I've
created an initial MyTargetSchedule.td
def MyTargetModel : SchedMachineModel {
// HW can decode 2 instructions per cycle.
let IssueWidth = 2;
let LoadLatency = 4;
let MispredictPenalty = 16;
// This flag is set to allow the
2014 May 14
0
[RFC PATCH v1 04/16] drm/nouveau: require reservations for nouveau_fence_sync and nouveau_bo_fence
This will ensure we always hold the required lock when calling those functions.
---
drivers/gpu/drm/nouveau/nouveau_bo.c | 2 ++
drivers/gpu/drm/nouveau/nouveau_display.c | 17 +++++++++++++----
2 files changed, 15 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/nouveau_bo.c b/drivers/gpu/drm/nouveau/nouveau_bo.c
index b6dc85c614be..33eb7164525a 100644
---
2011 Mar 08
0
Slices and reservations Was: Re: How long should an empty destroy take?
Hi,
instead of slicing and/or partitioning a drive one can also limit the
capacity the drive reports the controller and OS. This is what oem''s
do to ensure that drives from different manufacturers and revisions
all have the same capacity.
Different routes need to be followed for (S)ATA and SCSI/SAS drives,
because of different command sets. I''ve no experience with setting the
2011 May 20
2
scsi3 persistent reservations in cluster storage fencing
I'm interested in the idea of sharing a bunch of SAS JBOD devices
between two CentOS servers in an active-standby HA cluster sort of
arrangement, and found something about using scsi3 persistent
reservations as a fencing method. I'm not finding a lot of specifics
about how this works, or how you configure two initiator systems on a
SAS chain. I don't have any suitable
2011 Jul 26
0
[PATCH] Btrfs: use bytes_may_use for all ENOSPC reservations
We have been using bytes_reserved for metadata reservations, which is wrong
since we use that to keep track of outstanding reservations from the allocator.
This resulted in us doing a lot of silly things to make sure we don''t allocate a
bunch of metadata chunks since we never had a real view of how much space was
actually in use by metadata.
There are a lot of fixes in here to make this
2011 Jul 27
0
[PATCH] Btrfs: use bytes_may_use for all ENOSPC reservations V2
We have been using bytes_reserved for metadata reservations, which is wrong
since we use that to keep track of outstanding reservations from the allocator.
This resulted in us doing a lot of silly things to make sure we don''t allocate a
bunch of metadata chunks since we never had a real view of how much space was
actually in use by metadata.
There are a lot of fixes in here to make this