* Implements scalable size queries for MVTs, split out from D53137.
* Contains a fix for FindMemType to avoid using scalable vector type
to contain non-scalable types.
* Explicit casts for several places where implicit integer sign
changes or promotion from 32 to 64 bits caused problems.
* CodeGenDAGPatterns will treat scalable and non-scalable vector types
as different.
Reviewers: greened, cameron.mcinally, sdesmalen, rovka
Reviewed By: rovka
Differential Revision: https://reviews.llvm.org/D66871
This really should have been part of 366765. For some reason, I forgot to handle the corresponding load side, and the readable test cases (using deopt vs statepoints) turned out to be overly reduced. Oops.
As seen in the test change, the problem was that we were using a load with alignment expectations rather than the unaligned variant when the stack alignment was less than that prefered type alignment.
llvm-svn: 367718
We were silently using the ABI alignment for all of the stores generated for deopt and gc values. We'd gotten the alignment of the stack slot itself properly reduced (via MachineFrameInfo's clamping), but having the MMO on the store incorrect was enough for us to generate an aligned store to a unaligned location.
The simplest fix would have been to just pass the alignment to the helper function, but once we do that, the helper function doesn't really help. So, inline it and directly call the MMO version of DAG.getStore with a properly constructed MMO.
Note that there's a separate performance possibility here. Even if we *can* realign stacks, we probably don't *want to* if all of the stores are in slowpaths. But that's a later patch, if at all. :)
llvm-svn: 366765
The existing statepoint lowering code does something odd; it adds machine memory operands post instruction selection. This was copied from the stackmap/patchpoint implementation, but appears to be non-idiomatic.
This change is largely NFC. It moves the MMO creation logic into SelectionDAG building. It ends up not quite being NFC because the size of the stack slot is reflected in the MMO. The old code blindly used pointer size for the MMO size, which appears to have always been incorrect for larger values. It just happened nothing actually relied on the MMOs, so it worked out okay.
For context, I'm planning on removing the MOVolatile flag from these in a future commit, and then removing the MOStore flag from deopt spill slots in a separate one. Doing so is motivated by a small test case where we should be able to better schedule spill slots, but don't do so due to a memory use/def implied by the statepoint.
Differential Revision: https://reviews.llvm.org/D59106
llvm-svn: 355953
`CallBase` class rather than `CallSite` wrappers.
I pushed this change down through most of the statepoint infrastructure,
completely removing the use of CallSite where I could reasonably do so.
I ended up making a couple of cut-points: generic call handling
(instcombine, TLI, SDAG). As soon as it hit truly generic handling with
users outside the immediate code, I simply transitioned into or out of
a `CallSite` to make this a reasonable sized chunk.
Differential Revision: https://reviews.llvm.org/D56122
llvm-svn: 353660
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
Summary:
If a given liveness arg of STATEPOINT is at a fixed frame index
(e.g. a function argument passed on stack), prefer to use this
fixed location even the address is also in a register. If we use
the register it will generate a spill, which is not necessary
since the fixed frame index can be directly recorded in the stack
map.
Patch by Cherry Zhang <cherryyz@google.com>.
Reviewers: thanm, niravd, reames
Reviewed By: reames
Subscribers: cherryyz, reames, anna, arphaman, llvm-commits
Differential Revision: https://reviews.llvm.org/D53889
llvm-svn: 347998
This is used by llvm tblgen as well as by LLVM Targets, so the only
common place is Support for now. (maybe we need another target for these
sorts of things - but for now I'm at least making them correct & we can
make them better if/when people have strong feelings)
llvm-svn: 328395
This is needed for cases when the memory access is not as big as the width of
the data type. For instance, storing i1 (1 bit) would be done in a byte (8
bits).
Using 'BitSize >> 3' (or '/ 8') would e.g. give the memory access of an i1 a
size of 0, which for instance makes alias analysis return NoAlias even when
it shouldn't.
There are no tests as this was done as a follow-up to the bugfix for the case
where this was discovered (r318824). This handles more similar cases.
Review: Björn Petterson
https://reviews.llvm.org/D40339
llvm-svn: 319173
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).
llvm-svn: 318490
By target hookifying getRegisterType, getNumRegisters, getVectorBreakdown,
backends can request that LLVM to scalarize vector types for calls
and returns.
The MIPS vector ABI requires that vector arguments and returns are passed in
integer registers. With SelectionDAG's new hooks, the MIPS backend can now
handle LLVM-IR with vector types in calls and returns. E.g.
'call @foo(<4 x i32> %4)'.
Previously these cases would be scalarized for the MIPS O32/N32/N64 ABI for
calls and returns if vector types were not legal. If vector types were legal,
a single 128bit vector argument would be assigned to a single 32 bit / 64 bit
integer register.
By teaching the MIPS backend to inspect the original types, it can now
implement the MIPS vector ABI which requires a particular method of
scalarizing vectors.
Previously, the MIPS backend relied on clang to scalarize types such as "call
@foo(<4 x float> %a) into "call @foo(i32 inreg %1, i32 inreg %2, i32 inreg %3,
i32 inreg %4)".
This patch enables the MIPS backend to take either form for vector types.
The previous version of this patch had a "conditional move or jump depends on
uninitialized value".
Reviewers: zoran.jovanovic, jaydeep, vkalintiris, slthakur
Differential Revision: https://reviews.llvm.org/D27845
llvm-svn: 305083
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.
I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.
This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.
Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).
llvm-svn: 304787
We'd called this "vm state" in the early days, but have long since standardized on calling it "deopt" in line with the operand bundle tag. Fix a few cases we'd missed.
llvm-svn: 304607
Summary:
There are several places in the codebase that try to calculate a maximum value in a Statistic object. We currently do this in one of two ways:
MaxNumFoo = std::max(MaxNumFoo, NumFoo);
or
MaxNumFoo = (MaxNumFoo > NumFoo) ? MaxNumFoo : NumFoo;
The first version reads from MaxNumFoo one time and uncontionally rwrites to it. The second version possibly reads it twice depending on the result of the first compare. But we have no way of knowing if the value was changed by another thread between the reads and the writes.
This patch adds a method to the Statistic object that can ensure that we only store if our value is the max and the previous max didn't change after we read it. If it changed we'll recheck if our value should still be the max or not and try again.
This spawned from an audit I'm trying to do of all places we uses the implicit conversion to unsigned on the Statistics objects. See my previous thread on llvm-dev https://groups.google.com/forum/#!topic/llvm-dev/yfvxiorKrDQ
Reviewers: dberlin, chandlerc, hfinkel, dblaikie
Reviewed By: chandlerc
Subscribers: llvm-commits, sanjoy
Differential Revision: https://reviews.llvm.org/D33301
llvm-svn: 303318
Summary:
The type of the target frame index is intptr, not the type of the value we're
going to store into it. Without this change we crash in the attached test case
when trying to type-legalize a TargetFrameIndex.
Patchpoint lowering types the target frame index as intptr as well.
Reviewers: reames, bogner, arsenm
Subscribers: arsenm, mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D32256
llvm-svn: 301566
This reverts commit r299766. This change appears to have broken the MIPS
buildbots. Reverting while I investigate.
Revert "[mips] Remove usage of debug only variable (NFC)"
This reverts commit r299769. Follow up commit.
llvm-svn: 299788
By target hookifying getRegisterType, getNumRegisters, getVectorBreakdown,
backends can request that LLVM to scalarize vector types for calls
and returns.
The MIPS vector ABI requires that vector arguments and returns are passed in
integer registers. With SelectionDAG's new hooks, the MIPS backend can now
handle LLVM-IR with vector types in calls and returns. E.g.
'call @foo(<4 x i32> %4)'.
Previously these cases would be scalarized for the MIPS O32/N32/N64 ABI for
calls and returns if vector types were not legal. If vector types were legal,
a single 128bit vector argument would be assigned to a single 32 bit / 64 bit
integer register.
By teaching the MIPS backend to inspect the original types, it can now
implement the MIPS vector ABI which requires a particular method of
scalarizing vectors.
Previously, the MIPS backend relied on clang to scalarize types such as "call
@foo(<4 x float> %a) into "call @foo(i32 inreg %1, i32 inreg %2, i32 inreg %3,
i32 inreg %4)".
This patch enables the MIPS backend to take either form for vector types.
Reviewers: zoran.jovanovic, jaydeep, vkalintiris, slthakur
Differential Revision: https://reviews.llvm.org/D27845
llvm-svn: 299766
The stack slot reuse code had a really amusing bug. We ended up only reusing a stack slot exact once (initial use + reuse) within a basic block. If we had a third statepoint to process, we ended up allocating a new set of stack slots. If we crossed a basic block boundary, the set got cleared. As a result, code which is invoke heavy doesn't see the problem, but multiple calls within a basic block does. Net result: as we optimize invokes into calls, lowering gets worse.
The root error here is that the bitmap uses by the custom allocator wasn't kept in sync. The result was that we ended up resizing the bitmap on the next statepoint (to handle the cross block case), reset the bit once, but then never reset it again.
Differential Revision: https://reviews.llvm.org/D25243
llvm-svn: 289509
This is a first step towards supporting deopt value lowering and reporting entirely with the register allocator. I hope to build on this in the near future to support live-on-return semantics, but I have a use case which allows me to test and investigate code quality with just the live-in semantics so I've chosen to start there. For those curious, my use cases is our implementation of the "__llvm_deoptimize" function we bind to @llvm.deoptimize. I'm choosing not to hard code that fact in the patch and instead make it configurable via function attributes.
The basic approach here is modelled on what is done for the "Live In" values on stackmaps and patchpoints. (A secondary goal here is to remove one of the last barriers to merging the pseudo instructions.) We start by adding the operands directly to the STATEPOINT SDNode. Once we've lowered to MI, we extend the remat logic used by the register allocator to fold virtual register uses into StackMap::Indirect entries as needed. This does rely on the fact that the register allocator rematerializes. If it didn't along some code path, we could end up with more vregs than physical registers and fail to allocate.
Today, we *only* fold in the register allocator. This can create some weird effects when combined with arguments passed on the stack because we don't fold them appropriately. I have an idea how to fix that, but it needs this patch in place to work on that effectively. (There's some weird interaction with the scheduler as well, more investigation needed.)
My near term plan is to land this patch off-by-default, experiment in my local tree to identify any correctness issues and then start fixing codegen problems one by one as I find them. Once I have the live-in lowering fully working (both correctness and code quality), I'm hoping to move on to the live-on-return semantics. Note: I don't have any *known* miscompiles with this patch enabled, but I'm pretty sure I'll find at least a couple. Thus, the "experimental" tag and the fact it's off by default.
Differential Revision: https://reviews.llvm.org/D24000
llvm-svn: 280250
Summary:
Instead, we take a single flags arg (a bitset).
Also add a default 0 alignment, and change the order of arguments so the
alignment comes before the flags.
This greatly simplifies many callsites, and fixes a bug in
AMDGPUISelLowering, wherein the order of the args to getLoad was
inverted. It also greatly simplifies the process of adding another flag
to getLoad.
Reviewers: chandlerc, tstellarAMD
Subscribers: jholewinski, arsenm, jyknight, dsanders, nemanjai, llvm-commits
Differential Revision: http://reviews.llvm.org/D22249
llvm-svn: 275592
Previously, we were using isGCRelocate predicates. Using a subclass of IntrinsicInst is far more idiomatic. The refactoring also enables a couple of minor simplifications and code sharing.
llvm-svn: 266098
While preserving the return value for @llvm.experimental.deoptimize at
the IR level is useful during mid-level optimization, doing so at the
machine instruction level requires generating some extra code and a
return that is non-ideal. This change has LLVM lower
```
%val = call @llvm.experimental.deoptimize
ret %val
```
to effectively
```
call @__llvm_deoptimize()
unreachable
```
instead.
llvm-svn: 265502
Earlier we were ignoring varargs in LowerCallSiteWithDeoptBundle because
populateCallLoweringInfo does not set CallLoweringInfo::IsVarArg.
llvm-svn: 264354
Summary:
Only adds support for "naked" calls to llvm.experimental.deoptimize.
Support for round-tripping through RewriteStatepointsForGC will come
as a separate patch (should be simpler than this one).
Reviewers: reames
Subscribers: sanjoy, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D18429
llvm-svn: 264329
Given that StatepointLowering now uniques derived pointers before
putting them in the per-statepoint spill map, we may end up with missing
entries for derived pointers when we visit a gc.relocate on a pointer
that was de-duplicated away.
Fix this by keeping two maps, one mapping gc pointers to their
de-duplicated values, and one mapping a de-duplicated value to the slot
it is spilled in.
llvm-svn: 264320
Now that StatepointLoweringInfo represents base pointers, derived
pointers and gc relocates as SmallVectors and not ArrayRefs, we no
longer need to allocate "backing storage" on stack in LowerStatepoint.
So elide the backing storage, and inline the trivial body of
getIncomingStatepointGCValues.
llvm-svn: 264128
Summary:
After this change, deopt operand bundles can be lowered directly by
SelectionDAG into STATEPOINT instructions (which are then lowered to a
call or sequence of nop, with an associated __llvm_stackmaps entry0.
This obviates the need to round-trip deoptimization state through
gc.statepoint via RewriteStatepointsForGC.
Reviewers: reames, atrick, majnemer, JosephTremoulet, pgavlin
Subscribers: sanjoy, mcrosier, majnemer, llvm-commits
Differential Revision: http://reviews.llvm.org/D18257
llvm-svn: 264015
Summary:
This is a step towards implementing "direct" lowering of calls and
invokes with deopt operand bundles into STATEPOINT nodes (as opposed to
having them mandatorily pass through RewriteStatepointsForGC, which is
the case today).
This change extracts out a `SelectionDAGBuilder::LowerAsStatepoint`
helper function that is able to lower a "statepoint like thing", and
uses it to lower `gc.statepoint` calls. This is an NFC now, but in a
later change we will use `LowerAsStatepoint` to directly lower calls and
invokes with operand bundles without going through an intermediate
`gc.statepoint` IR representation.
FYI: I expect `SelectionDAGBuilder::StatepointInfo` will evolve as I add
support for lowering non gc.statepoints, right now it is fairly tightly
coupled with an IR level `gc.statepoint`.
Reviewers: reames, pgavlin, JosephTremoulet
Subscribers: sanjoy, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D18106
llvm-svn: 263671
SelectionDAGBuilder::populateCallLoweringInfo is now used instead of
SelectionDAGBuilder::lowerCallOperands. The populateCallLoweringInfo
interface is more composable in face of design changes like
http://reviews.llvm.org/D18106
llvm-svn: 263663
Instead of running an explicit loop over `gc.relocate` calls hanging off
of a `gc.statepoint`, assert the validity of the type of the value being
relocated in `visitRelocate`.
llvm-svn: 263516
Now that we don't always add an element to AllocatedStackSlots if we
don't find a pre-existing unallocated stack slot, bumping
StatepointMaxSlotsRequired to `NumSlots + 1` is not correct. Instead
bump the statistic near the push_back, to
Builder.FuncInfo.StatepointStackSlots.size().
llvm-svn: 261348
The check on MFI->getObjectSize() has to be on the FrameIndex, not on
the index of the FrameIndex in AllocatedStackSlots. Weirdly, the tests
I added in rL261336 didn't catch this.
llvm-svn: 261347
NFCI. They key motivation here is that I'd like to use
SmallBitVector::all() in a later change. Also, using a bit vector here
seemed better in general.
The only interesting change here is that in the failure case of
allocateStackSlot, we no longer (the equivalent of) push_back(true) to
AllocatedStackSlots. As far as I can tell, this is fine, since we'd
never re-use those slots in the same StatepointLoweringState instance.
Technically there was no need to change the operator[] type accesses to
set() and test(), but I thought it'd be nice to make it obvious that
we're using something other than a std::vector like thing.
llvm-svn: 261337
allocateStackSlot did not consider the size of the value to be spilled
before deciding to re-use a spill slot. This was originally okay (since
originally we'd only ever spill pointers), but it became not okay when
we changed our scheme to directly spill vectors of pointers.
While this change fixes the bug pointed out, it has two performance
caveats:
- It matches spill slot and spillee size exactly, while in theory we
can spill, e.g., an 8 byte pointer into a 16 byte slot. This is
slightly complicated to fix since in the stackmaps section, we report
the size of the spill slot as the size of the "indirect value"; and
if they're no longer equivalent, we'll have to keep track of the
(indirect) value size separately from the stack slot size.
- It will "spuriously run out" of reusable slots, since we now have an
second check in the search loop in addition to the availablity
check (e.g. you had two free scalar slots, and you first ask for a
vector slot followed by a scalar slot). I'll fix this in a later
commit.
llvm-svn: 261336
Graham Hunter