This was exposed by PowerPC target enablement.
In ScheduleDAG, if we haven't seen any uses in this scheduling region,
we will create a dependence edge to ExitSU to model the live-out latency.
This is required for vreg defs with no in-region use, and prefetches with
no vreg def.
When we build NodeOrder in Scheduler, we ignore these boundary nodes.
However, when we check Succs in checkValidNodeOrder, we did not skip
them, so we still assume all the nodes have been sorted and in order in
Indices array. So when we call lower_bound() for ExitSU, it will return
Indices.end(), causing memory issues in following Node access.
Differential Revision: https://reviews.llvm.org/D63282
llvm-svn: 363329
Implement necessary target hooks to enable MachinePipeliner for P9 only.
The pass is off by default, can be enabled with -ppc-enable-pipeliner for P9.
Differential Revision: https://reviews.llvm.org/D62164
llvm-svn: 363085
The ISD::STRICT_ nodes used to implement the constrained floating-point
intrinsics are currently never passed to the target back-end, which makes
it impossible to handle them correctly (e.g. mark instructions are depending
on a floating-point status and control register, or mark instructions as
possibly trapping).
This patch allows the target to use setOperationAction to switch the action
on ISD::STRICT_ nodes to Legal. If this is done, the SelectionDAG common code
will stop converting the STRICT nodes to regular floating-point nodes, but
instead pass the STRICT nodes to the target using normal SelectionDAG
matching rules.
To avoid having the back-end duplicate all the floating-point instruction
patterns to handle both strict and non-strict variants, we make the MI
codegen explicitly aware of the floating-point exceptions by introducing
two new concepts:
- A new MCID flag "mayRaiseFPException" that the target should set on any
instruction that possibly can raise FP exception according to the
architecture definition.
- A new MI flag FPExcept that CodeGen/SelectionDAG will set on any MI
instruction resulting from expansion of any constrained FP intrinsic.
Any MI instruction that is *both* marked as mayRaiseFPException *and*
FPExcept then needs to be considered as raising exceptions by MI-level
codegen (e.g. scheduling).
Setting those two new flags is straightforward. The mayRaiseFPException
flag is simply set via TableGen by marking all relevant instruction
patterns in the .td files.
The FPExcept flag is set in SDNodeFlags when creating the STRICT_ nodes
in the SelectionDAG, and gets inherited in the MachineSDNode nodes created
from it during instruction selection. The flag is then transfered to an
MIFlag when creating the MI from the MachineSDNode. This is handled just
like fast-math flags like no-nans are handled today.
This patch includes both common code changes required to implement the
new features, and the SystemZ implementation.
Reviewed By: andrew.w.kaylor
Differential Revision: https://reviews.llvm.org/D55506
llvm-svn: 362663
The current design use DFA to do resource tracking in SMS,
and DFA only support InstrItins, and also has scaling limitation.
This patch extend SMS to allow Subtarget to use ProcResource in
InstrSchedModel instead.
Differential Revision: https://reviews.llvm.org/D62163
llvm-svn: 361919
Summary:
Both the input Value pointer and the returned Value
pointers in GetUnderlyingObjects are now declared as
const.
It turned out that all current (in-tree) uses of
GetUnderlyingObjects were trivial to update, being
satisfied with have those Value pointers declared
as const. Actually, in the past several of the users
had to use const_cast, just because of ValueTracking
not providing a version of GetUnderlyingObjects with
"const" Value pointers. With this patch we get rid
of those const casts.
Reviewers: hfinkel, materi, jkorous
Reviewed By: jkorous
Subscribers: dexonsmith, jkorous, jholewinski, sdardis, eraman, hiraditya, jrtc27, atanasyan, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61038
llvm-svn: 359072
Summary:
The basic idea here is to make it possible to use
MachineInstr::mayAlias also when the MachineInstr
is const (or the "Other" MachineInstr is const).
The addition of const in MachineInstr::mayAlias
then rippled down to the need for adding const
in several other places, such as
TargetTransformInfo::getMemOperandWithOffset.
Reviewers: hfinkel
Reviewed By: hfinkel
Subscribers: hfinkel, MatzeB, arsenm, jvesely, nhaehnle, hiraditya, javed.absar, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60856
llvm-svn: 358744
The isLoopCarriedDep function does not correctly compute loop
carried dependences when the array index offset is negative
or the stride is smallar than the access size.
Patch by Denis Antrushin.
Differential Revision: https://reviews.llvm.org/D60135
llvm-svn: 358233
Background: At the moment, we record the AtomicOrdering of an access in the MMO, but also mark any atomic access as volatile in SelectionDAG. I'm working towards separating that. See https://reviews.llvm.org/D57601 for context.
Update all usages of isVolatile in lib/CodeGen to preserve behaviour once atomic MMOs stop being also volatile. This is NFC in it's current form, but is essential for correctness once we make that final change.
It useful to keep in mind that AtomicSDNode is not a parent of LoadSDNode, StoreSDNode, or LSBaseSDNode. As a result, any call to isVolatile on one of those static types doesn't need a companion isAtomic check. We should probably adjust that class hierarchy long term, but for now, that seperation is useful.
I'm deliberately being conservative about handling. I want the change to stop adding volatile to be NFC itself, and then will work through places where we can be less conservative for atomics one by one in separate changes w/tests.
Differential Revision: https://reviews.llvm.org/D57596
llvm-svn: 352937
#pragma clang loop pipeline(disable)
Disable SWP optimization for the next loop.
“disable” is the only possible value.
#pragma clang loop pipeline_initiation_interval(number)
Set value of initiation interval for SWP
optimization to specified number value for
the next loop. Number is the positive value
greater than 0.
These pragmas could be used for debugging or reducing
compile time purposes. It is possible to disable SWP for
concrete loops to save compilation time or to find bugs
by not doing SWP to certain loops. It is possible to set
value of initiation interval to concrete number to save
compilation time by not doing extra pipeliner passes or
to check created schedule for specific initiation interval.
That is llvm part of the fix
Clang part of fix: https://reviews.llvm.org/D55710
Patch by Alexey Lapshin!
Differential Revision: https://reviews.llvm.org/D56403
llvm-svn: 351923
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Split MachinePipeliner code into header and cpp files to allow
inheritance from SwingSchedulerDAG.
This reapplies https://reviews.llvm.org/D56084 after moving the
implementation of the dump functions into the .cpp files. This fixes a
linker error when building with Clang modules enables and local
submodule visibility disabled.
Original patch by Lama Saba <lama.saba@intel.com>!
llvm-svn: 351077
This reverts commit rL350497
reported remaining issues seem to be unrelated to modules or this change.
more info: https://reviews.llvm.org/D56084
llvm-svn: 350621
Currently, instructions doing memory accesses through a base operand that is
not a register can not be analyzed using `TII::getMemOpBaseRegImmOfs`.
This means that functions such as `TII::shouldClusterMemOps` will bail
out on instructions using an FI as a base instead of a register.
The goal of this patch is to refactor all this to return a base
operand instead of a base register.
Then in a separate patch, I will add FI support to the mem op clustering
in the MachineScheduler.
Differential Revision: https://reviews.llvm.org/D54846
llvm-svn: 347746
The artificial dependencies are not real dependencies. In some cases, they
form circuits with bigger MII. However, they are used to schedule instructions
better.
Differential Revision: https://reviews.llvm.org/D53450
llvm-svn: 345319
Split MachinePipeliner code into header and cpp files to allow inheritance from SwingSchedulerDAG
Differential Revision: https://reviews.llvm.org/D53477
llvm-svn: 345008
In a loop, create artificial dependences between the source of a
COPY/REG_SEQUENCE to the use in next iteration.
Eg:
SRC ----Data Dep--> COPY
COPY ---Anti Dep--> PHI (implies, to be used in next iteration)
PHI ----Data Dep--> USE
This patches creates
USE ----Artificial Dep---> SRC
This will effectively schedule the COPY late to eliminate additional copies.
Before this patch, the schedule can be
SRC, COPY, USE : The COPY is used in next iteration and it needs to be
preserved.
After this patch, the schedule can be
USE, SRC, COPY : The COPY is used in next iteration and the live interval is
reduced.
Differential Revision: https://reviews.llvm.org/D53303
llvm-svn: 344748
In future, if we may add any new DAG mutations other than artificial dependencies,
the NodeNum may not be valid. Instead the index from topological schedule DAG can be
used as long as we update it with the DAG change.
Differential Revision: https://reviews.llvm.org/D53104
llvm-svn: 344283
This patch updates the DAG change to reflect in the topological ordering
of the nodes.
Differential Revision: https://reviews.llvm.org/D53105
llvm-svn: 344282
Moving away from UnknownSize is part of the effort to migrate us to
LocationSizes (e.g. the cleanup promised in D44748).
This doesn't entirely remove all of the uses of UnknownSize; some uses
require tweaks to assume that UnknownSize isn't just some kind of int.
This patch is intended to just be a trivial replacement for all places
where LocationSize::unknown() will Just Work.
llvm-svn: 344186
- Instead of having both `SUnit::dump(ScheduleDAG*)` and
`ScheduleDAG::dumpNode(ScheduleDAG*)`, just keep the latter around.
- Add `ScheduleDAG::dump()` and avoid code duplication in several
places. Implement it for different ScheduleDAG variants.
- Add `ScheduleDAG::dumpNodeName()` in favor of the `SUnit::print()`
functions. They were only ever used for debug dumping and putting the
function into ScheduleDAG is consistent with the `dumpNode()` change.
llvm-svn: 342520
The code that generates the loop definition operand for phis
in the epilog and kernel is incorrect in some cases.
In the kernel, when a phi refers to another phi, the code that
updates PhiOp2 needs to include the stage difference between
the two phis.
In the epilog, the check for using the loop definition instead
of the phi definition uses the StageDiffAdj value (the difference
between the phi stage and the loop definition stage), but the
adjustment is not needed to determine if the current stage
contains an iteration with the loop definition.
Differential Revision: https://reviews.llvm.org/D51167
llvm-svn: 340782
1. Change the software pipeliner to use unknown size instead of dropping
memory operands. It used to do it before, but MachineInstr::mayAlias
did not handle it correctly.
2. Recognize UnknownSize in MachineInstr::mayAlias.
3. Print and parse UnknownSize in MIR.
Differential Revision: https://reviews.llvm.org/D50339
llvm-svn: 340208
a generically extensible collection of extra info attached to
a `MachineInstr`.
The primary change here is cleaning up the APIs used for setting and
manipulating the `MachineMemOperand` pointer arrays so chat we can
change how they are allocated.
Then we introduce an extra info object that using the trailing object
pattern to attach some number of MMOs but also other extra info. The
design of this is specifically so that this extra info has a fixed
necessary cost (the header tracking what extra info is included) and
everything else can be tail allocated. This pattern works especially
well with a `BumpPtrAllocator` which we use here.
I've also added the basic scaffolding for putting interesting pointers
into this, namely pre- and post-instruction symbols. These aren't used
anywhere yet, they're just there to ensure I've actually gotten the data
structure types correct. I'll flesh out support for these in
a subsequent patch (MIR dumping, parsing, the works).
Finally, I've included an optimization where we store any single pointer
inline in the `MachineInstr` to avoid the allocation overhead. This is
expected to be the overwhelmingly most common case and so should avoid
any memory usage growth due to slightly less clever / dense allocation
when dealing with >1 MMO. This did require several ergonomic
improvements to the `PointerSumType` to reasonably support the various
usage models.
This also has a side effect of freeing up 8 bits within the
`MachineInstr` which could be repurposed for something else.
The suggested direction here came largely from Hal Finkel. I hope it was
worth it. ;] It does hopefully clear a path for subsequent extensions
w/o nearly as much leg work. Lots of thanks to Reid and Justin for
careful reviews and ideas about how to do all of this.
Differential Revision: https://reviews.llvm.org/D50701
llvm-svn: 339940
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.
In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.
Differential Revision: https://reviews.llvm.org/D43624
llvm-svn: 332240
See r331124 for how I made a list of files missing the include.
I then ran this Python script:
for f in open('filelist.txt'):
f = f.strip()
fl = open(f).readlines()
found = False
for i in xrange(len(fl)):
p = '#include "llvm/'
if not fl[i].startswith(p):
continue
if fl[i][len(p):] > 'Config':
fl.insert(i, '#include "llvm/Config/llvm-config.h"\n')
found = True
break
if not found:
print 'not found', f
else:
open(f, 'w').write(''.join(fl))
and then looked through everything with `svn diff | diffstat -l | xargs -n 1000 gvim -p`
and tried to fix include ordering and whatnot.
No intended behavior change.
llvm-svn: 331184
There are cases when individual NodeSets can be equal with respect to
the ordering criteria. Since they are stored in an ordered container,
use stable_sort to preserve the relative order of equal NodeSets.
This should remove non-determinism discovered by shuffling done in
llvm::sort with expensive checks enabled.
llvm-svn: 329915
Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.
To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.
Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer the comments section in D44363 for a list of all the required patches.
Reviewers: bogner, rnk, MatzeB, RKSimon
Reviewed By: rnk
Subscribers: JDevlieghere, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D45133
llvm-svn: 329435
First, we change the heuristic that is used to ignore the recurrent
node-sets in the node ordering. In certain cases it's not important
to focus on the recurrent node-sets. Instead, the algorithm begins
by considering all the instructions in the node ordering step.
Second, a minor change to the bottom up traversal, which needs to
consider loop carried dependences (modeled as anti dependences).
Previously, these instructions were skipped, which caused problems
because the instruction ends up having both predecessors and
sucessors in the schedule.
Third, consider anti-dependences as a tie breaker when choosing
between instructions in the node ordering. We want to make sure
that the source of the anti-dependence does not end up with both
predecesssors and sucessors in the final node ordering.
Patch by Brendon Cahoon.
llvm-svn: 328554
The pipeliner must add a loop carried dependence between two memory
operations if the base register is not an affine (linear) exression.
The current implementation doesn't check how the base register is
defined, which allows non-affine expressions, and then the pipeliner
does not add a loop carried dependence when one is needed.
This patch adds code to isLoopCarriedOrder that checks if the base
register of the memory operations is defined by a phi, and the loop
definition for the phi is a constant increment value. This is a very
simple check for a linear expression.
Patch by Brendon Cahoon.
llvm-svn: 328550
The pipeliner is not adding a dependence edge for a loop carried
dependence, and ends up scheduling a load from iteration n prior
to an aliased store in iteration n-1.
The code that adds the loop carried dependences in the pipeliner
doesn't check if the memory objects for loads and stores are
"identified" (i.e., distinct) objects. If they are not, then the
code that adds the dependences needs to be conservative. The
objects can be used to check dependences only when they are
distinct objects.
The code that checks for loop carried dependences has been updated
to classify loads and stores that are not identified as "unknown"
values. A store with an "unknown" value can potentially create
a loop carried dependence with any pending load.
Patch by Brendon Cahoon.
llvm-svn: 328547
The phi renaming code in the pipeliner uses the wrong value when
rewriting phi uses, which results in an undefined value. In this
case, the original phi is no longer needed due to the order of
instruction in the pipelined loop. The pipeliner was assuming, in
this case, the the phi loop definition should be used to
rewrite the uses. However, the pipeliner needs to check to make
sure that the loop definition has already been scheduled. If not,
then the phi initial value needs to be used instead.
Patch by Brendon Cahoon.
llvm-svn: 328545
