We keep a few iterators into the basic block we're selecting while
performing FastISel. Usually this is fine, but occasionally code wants
to remove already-emitted instructions. When this happens we have to be
careful to update those iterators so they're not pointint at dangling
memory.
llvm-svn: 349365
The Load/Store Optimizer runs before Machine Block Placement. At O3 the
Tail Duplication Threshold is set to 4 instructions and this can create
new opportunities for the Load/Store Optimizer. It seems worthwhile to
run it once again.
llvm-svn: 349338
Fix the logic in the definition of the `ExynosShiftExPred` as a more
specific version of `ExynosShiftPred`. But, since `ExynosShiftExPred` is
not used yet, this change has NFC.
llvm-svn: 349091
Summary:
Emit COFF header when printing out the function. This is important as the
header contains two important pieces of information: the storage class for the
symbol and the symbol type information. This bit of information is required for
the linker to correctly identify the type of symbol that it is dealing with.
This patch mimics X86 and ARM COFF behavior for function header emission.
Reviewers: rnk, mstorsjo, compnerd, TomTan, ssijaric
Reviewed By: mstorsjo
Subscribers: dmajor, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D55535
llvm-svn: 348875
https://reviews.llvm.org/D55294
Previously MachineIRBuilder::buildInstr used to accept variadic
arguments for sources (which were either unsigned or
MachineInstrBuilder). While this worked well in common cases, it doesn't
allow us to build instructions that have multiple destinations.
Additionally passing in other optional parameters in the end (such as
flags) is not possible trivially. Also a trivial call such as
B.buildInstr(Opc, Reg1, Reg2, Reg3)
can be interpreted differently based on the opcode (2defs + 1 src for
unmerge vs 1 def + 2srcs).
This patch refactors the buildInstr to
buildInstr(Opc, ArrayRef<DstOps>, ArrayRef<SrcOps>)
where DstOps and SrcOps are typed unions that know how to add itself to
MachineInstrBuilder.
After this patch, most invocations would look like
B.buildInstr(Opc, {s32, DstReg}, {SrcRegs..., SrcMIBs..});
Now all the other calls (such as buildAdd, buildSub etc) forward to
buildInstr. It also makes it possible to build instructions with
multiple defs.
Additionally in a subsequent patch, we should make it possible to add
flags directly while building instructions.
Additionally, the main buildInstr method is now virtual and other
builders now only have to override buildInstr (for say constant
folding/cseing) is straightforward.
Also attached here (https://reviews.llvm.org/F7675680) is a clang-tidy
patch that should upgrade the API calls if necessary.
llvm-svn: 348815
This patch restricts the capability of G_MERGE_VALUES, and uses the new
G_BUILD_VECTOR and G_CONCAT_VECTORS opcodes instead in the appropriate places.
This patch also includes AArch64 support for selecting G_BUILD_VECTOR of <4 x s32>
and <2 x s64> vectors.
Differential Revisions: https://reviews.llvm.org/D53629
llvm-svn: 348788
Refactor the scheduling predicates based on `MCInstPredicate`. In this
case, for the Exynos processors.
Differential revision: https://reviews.llvm.org/D55345
llvm-svn: 348774
Refactor the scheduling predicates based on `MCInstPredicate`. Augment the
number of helper predicates used by processor specific predicates.
Differential revision: https://reviews.llvm.org/D55375
llvm-svn: 348768
Adds fatal errors for any target that does not support the Tiny or Kernel
codemodels by rejigging the getEffectiveCodeModel calls.
Differential Revision: https://reviews.llvm.org/D50141
llvm-svn: 348585
This patch splits backend features currently
hidden behind architecture versions.
For example, currently the only way to activate
complex numbers extension is targeting an v8.3
architecture, where after the patch this extension
can be added separately.
This refactoring is required by the new command lines proposal:
http://lists.llvm.org/pipermail/llvm-dev/2018-September/126346.html
Reviewers: DavidSpickett, olista01, t.p.northover
Subscribers: kristof.beyls, bryanpkc, javed.absar, pbarrio
Differential revision: https://reviews.llvm.org/D54633
--
It was reverted in rL348249 due a build bot failure in one of the
regression tests:
http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win/builds/14386
The problem seems to be that FileCheck behaves
different in windows and linux. This new patch
splits the test file in multiple,
and does more exact pattern matching attempting
to circumvent the issue.
llvm-svn: 348493
The code emitting AND-subtrees used to check whether any of the operands
was an OR in order to figure out if the result needs to be negated.
However the OR could be hidden in further subtrees and not immediately
visible.
Change the code so that canEmitConjunction() determines whether the
result of the generated subtree needs to be negated. Cleanup emission
logic to use this. I also changed the code a bit to make all negation
decisions early before we actually emit the subtrees.
This fixes http://llvm.org/PR39550
Differential Revision: https://reviews.llvm.org/D54137
llvm-svn: 348444
https://reviews.llvm.org/D54980
This provides a standard API across GISel passes to observe and notify
passes about changes (insertions/deletions/mutations) to MachineInstrs.
This patch also removes the recordInsertion method in MachineIRBuilder
and instead provides method to setObserver.
Reviewed by: vkeles.
llvm-svn: 348406
Functions annotated with `__fastcall` or `__attribute__((__fastcall__))`
or `__attribute__((__swiftcall__))` may contain SEH handlers even on
Win64. This matches the behaviour of cl which allows for
`__try`/`__except` inside a `__fastcall` function. This was detected
while trying to self-host clang on Windows ARM64.
llvm-svn: 348337
We previously disabled this in r323371 because of a bug where we selected an
extending load, but didn't delete the old G_LOAD, resulting in two loads being
generated for volatile loads.
Since we now have dedicated G_SEXTLOAD/G_ZEXTLOAD operations, and that the
tablegen patterns should no longer be able to select (ext(load x)) patterns, it
should be safe to re-enable it.
The old test case should still work as expected.
llvm-svn: 348320
The comment was misplaced, and the code didn't do what the comment indicated,
namely ignoring the varargs portion when computing the local stack size of a
funclet in emitEpilogue. This results in incorrect offset computations within
funclets that are contained in vararg functions.
Differential Revision: https://reviews.llvm.org/D55096
llvm-svn: 348222
This moves the stack check logic into a lambda within getOutliningCandidateInfo.
This allows us to be less conservative with stack checks. Whether or not a
stack instruction is safe to outline is dependent on the frame variant and call
variant of the outlined function; only in cases where we modify the stack can
these be unsafe.
So, if we move that logic later, when we're looking at an individual candidate,
we can make better decisions here.
This gives some code size savings as a result.
llvm-svn: 348220
If we dropped too many candidates to be beneficial when dropping candidates
that modify the stack, there's no reason to check for other cost model
qualities.
llvm-svn: 348219
If it's a bigger code size win to drop candidates that require stack fixups
than to demote every candidate to that variant, the outliner should do that.
This happens if the number of bytes taken by calls to functions that don't
require fixups, plus the number of bytes that'd be left is less than the
number of bytes that it'd take to emit a save + restore for all candidates.
Also add tests for each possible new behaviour.
- machine-outliner-compatible-candidates shows that when we have candidates
that don't use the stack, we can use the default call variant along with the
no save/regsave variant.
- machine-outliner-all-stack shows that when it's better to fix up the stack,
we still will demote all candidates to that case
- machine-outliner-drop-stack shows that we can discard candidates that
require stack fixups when it would be beneficial to do so.
llvm-svn: 348168
Summary:
SSBS (Speculative Store Bypass Safe) is only mandatory from 8.5
onwards but is optional from Armv8.0-A. This patch adds a command
line option to enable SSBS, as it was previously only possible to
enable by selecting -march=armv8.5-a.
Similar patch upstream in GNU binutils:
https://sourceware.org/ml/binutils/2018-09/msg00274.html
Reviewers: olista01, samparker, aemerson
Reviewed By: samparker
Subscribers: javed.absar, kristof.beyls, kristina, llvm-commits
Differential Revision: https://reviews.llvm.org/D54629
llvm-svn: 348137
This patch splits backend features currently
hidden behind architecture versions.
For example, currently the only way to activate
complex numbers extension is targeting an v8.3
architecture, where after the patch this extension
can be added separately.
This refactoring is required by the new command lines proposal:
http://lists.llvm.org/pipermail/llvm-dev/2018-September/126346.html
Reviewers: DavidSpickett, olista01, t.p.northover
Subscribers: kristof.beyls, bryanpkc, javed.absar, pbarrio
Differential revision: https://reviews.llvm.org/D54633
llvm-svn: 348121
If we know that we'll definitely save LR to a register, there's no reason to
pre-check whether or not a stack instruction is unsafe to fix up.
This makes it so that we check for that condition before mapping instructions.
This allows us to outline more, since we don't pessimise as many instructions.
Also update some tests, since we outline more.
llvm-svn: 348081
Instead of treating the outlined functions for these as distinct frames, they
should be combined into one case. Neither allows for stack fixups, and both
generate the same frame. Thus, they ought to be considered one case.
This makes the code far easier to understand, for one thing. It also offers
some small code size improvements. It's fairly rare to see a class of outlined
functions that doesn't fall entirely into one variant (on CTMark anyway). It
does happen from time to time though.
This mostly offers some serious simplification.
Also update the test to show the added functionality.
llvm-svn: 348036
All that you can legitimately do with the CFI for a nounwind function
is get a backtrace, and adjusting the SCS register is not (currently)
required for this purpose.
Differential Revision: https://reviews.llvm.org/D54988
llvm-svn: 348035
It makes more sense to order FI-based memops in descending order when
the stack goes down. This allows offsets to stay "consecutive" and allow
easier pattern matching.
llvm-svn: 347906
I believe we should be legalizing these with the rest of vector binary operations. If any custom lowering is required for these nodes, this will give the DAG combine between LegalizeVectorOps and LegalizeDAG to run on the custom code before constant build_vectors are lowered in LegalizeDAG.
I've moved MULHU/MULHS handling in AArch64 from Lowering to isel. Moving the lowering earlier caused build_vector+extract_subvector simplifications to kick in which made the generated code worse.
Differential Revision: https://reviews.llvm.org/D54276
llvm-svn: 347902
Change meaning of TargetOptions::EnableGlobalISel. The flag was
previously set only when a target switched on GlobalISel but it is now
always set when the GlobalISel pipeline is enabled. This makes the flag
consistent with TargetOptions::EnableFastISel and allows its use in
other parts of the compiler to determine when GlobalISel is enabled.
The EnableGlobalISel flag had previouly only one use in
TargetPassConfig::isGlobalISelAbortEnabled(). The method used its value
to determine if GlobalISel was enabled by a target and returned false in
such a case. To preserve the current behaviour, a new flag
TargetOptions::GlobalISelAbort is introduced to separately record the
abort behaviour.
Differential Revision: https://reviews.llvm.org/D54518
llvm-svn: 347861
Before this patch, the following stores in `merge_fail` would fail to be
merged, while they would get merged in `merge_ok`:
```
void use(unsigned long long *);
void merge_fail(unsigned key, unsigned index)
{
unsigned long long args[8];
args[0] = key;
args[1] = index;
use(args);
}
void merge_ok(unsigned long long *dst, unsigned a, unsigned b)
{
dst[0] = a;
dst[1] = b;
}
```
The reason is that `getMemOpBaseImmOfs` would return false for FI base
operands.
This adds support for this.
Differential Revision: https://reviews.llvm.org/D54847
llvm-svn: 347747
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
Refactor the scheduling predicates based on `MCInstPredicate`. In this
case, `AArch64InstrInfo::hasExtendedReg()`.
Differential revision: https://reviews.llvm.org/D54822
llvm-svn: 347599
Refactor the scheduling predicates based on `MCInstPredicate`. In this
case, `AArch64InstrInfo::hasShiftedReg()`.
Differential revision: https://reviews.llvm.org/D54820
llvm-svn: 347598
Refactor the scheduling predicates based on `MCInstPredicate`. In this
case, `AArch64InstrInfo::isScaledAddr()`
Differential revision: https://reviews.llvm.org/D54777
llvm-svn: 347597
Summary:
Add a hook to the GCMetadataPrinter for emitting stack maps in
custom format. The hook will be called at stack map generation
time. The default stack map format is used if there is no hook.
For this to be useful a few data structures and accessors are
exposed from the StackMaps class, so the custom printer can
access the stack map data.
This patch authored by Cherry Zhang <cherryyz@google.com>.
Reviewers: thanm, apilipenko, reames
Reviewed By: reames
Subscribers: reames, apilipenko, nemanjai, javed.absar, kbarton, jsji, llvm-commits
Differential Revision: https://reviews.llvm.org/D53892
llvm-svn: 347584
A consequence of r347274 is that SCALAR_TO_VECTOR can be converted into
BUILD_VECTOR by SimplifyDemandedBits, but LowerBUILD_VECTOR can turn
BUILD_VECTOR into SCALAR_TO_VECTOR so we get an infinite loop.
Fix this by making LowerBUILD_VECTOR not do this transformation for those
vectors that would get transformed back, i.e. BUILD_VECTOR of a single-element
constant vector. Doing that means we get a DUP, which we then need to recognise
in ISel as a copy.
llvm-svn: 347456
This patch defines an interleaved-load-combine pass. The pass searches
for ShuffleVector instructions that represent interleaved loads. Matches are
converted such that they will be captured by the InterleavedAccessPass.
The pass extends LLVMs capabilities to use target specific instruction
selection of interleaved load patterns (e.g.: ld4 on Aarch64
architectures).
Differential Revision: https://reviews.llvm.org/D52653
llvm-svn: 347208
When unwinding past a function that uses shadow call stack, we must
subtract 8 from the value of the x18 register. This patch causes us
to emit a call frame instruction that causes that to happen.
Differential Revision: https://reviews.llvm.org/D54609
llvm-svn: 347089
Using the MBB flags, we can tell if X16/X17/NZCV are unused in a block,
and also not live out.
If this holds for all MBBs, then we can avoid checking for liveness on
that candidate. Furthermore, if it holds for an individual candidate's
MBB, then we can avoid checking for liveness on that candidate.
llvm-svn: 346901
If we keep track of if the ContainsCalls bit is set in the MBB flags for each
candidate, then we have a better chance of not checking the candidate for calls
at all.
This saves quite a few checks in some CTMark tests (~200 in Bullet, for
example.)
llvm-svn: 346816
We already determine a bunch of information about an MBB in
getMachineOutlinerMBBFlags. We can reuse that information to avoid calculating
things that must be false/true.
The first thing we can easily check is if an outlined sequence could ever
contain calls. There's no reason to walk over the outlined range, checking for
calls, if we already know that there are no calls in the block containing the
sequence.
llvm-svn: 346809
Since we never outline anything with fewer than 2 occurrences, there's no
reason to compute cost model information if there's less than that.
llvm-svn: 346803
Turns out it's way simpler to do this check with one LRU. Instead of
maintaining two, just keep one. Check if each of the registers is available,
and then check if it's a live out from the block. If it's a live out, but
available in the block, we know we're in an unsafe case.
llvm-svn: 346721
Instead of returning Flags, return true if the MBB is safe to outline from.
This lets us check for unsafe situations, like say, in AArch64, X17 is live
across a MBB without being defined in that MBB. In that case, there's no point
in performing an instruction mapping.
llvm-svn: 346718
This is a long-awaited follow-up suggested in D33578. Since then, we've picked up even more
opportunities for vector narrowing from changes like D53784, so there are a lot of test diffs.
Apart from 2-3 strange cases, these are all wins.
I've structured this to be no-functional-change-intended for any target except for x86
because I couldn't tell if AArch64, ARM, and AMDGPU would improve or not. All of those
targets have existing regression tests (4, 4, 10 files respectively) that would be
affected. Also, Hexagon overrides the shouldReduceLoadWidth() hook, but doesn't show
any regression test diffs. The trade-off is deciding if an extra vector load is better
than a single wide load + extract_subvector.
For x86, this is almost always better (on paper at least) because we often can fold
loads into subsequent ops and not increase the official instruction count. There's also
some unknown -- but potentially large -- benefit from using narrower vector ops if wide
ops are implemented with multiple uops and/or frequency throttling is avoided.
Differential Revision: https://reviews.llvm.org/D54073
llvm-svn: 346595
This patch adds support for funclets in frame lowering and ISel
lowering. Together with D50288 and D50166, it enables C++ exception
handling.
Patch by Sanjin Sijaric, with some fixes by me.
Differential Revision: https://reviews.llvm.org/D51524
llvm-svn: 346568
Summary:
This simplifies the code and moves everything to tablegen for consistency. This
also prepares the ground for adding issue counters.
Reviewers: gchatelet, john.brawn, jsji
Subscribers: nemanjai, mgorny, javed.absar, kbarton, tschuett, llvm-commits
Differential Revision: https://reviews.llvm.org/D54297
llvm-svn: 346489
In this context, usesWindowsCFI() is basically the same thing as
isOSWindows(), but it makes the relevant property of the target
more explicit.
llvm-svn: 346366
Like the comment says, this isn't the most efficient fix in terms of
codesize, but it works.
Differential Revision: https://reviews.llvm.org/D54129
llvm-svn: 346358
Cleanup CCMP pattern matching code in preparation for review/bugfix:
- Rename `isConjunctionDisjunctionTree()` to `canEmitConjunction()`
(it won't accept arbitrary disjunctions and is really about whether we
can transform the subtree into a conjunction that we can emit).
- Rename `emitConjunctionDisjunctionTree()` to `emitConjunction()`
llvm-svn: 346203
The main caller of this already has an MVT and several targets called getSimpleVT inside without checking isSimple. This makes the simpleness explicit.
llvm-svn: 346180
Summary:
This function was causing a crash when `MaxElements == 1` because
it was trying to create a single element vector type.
Reviewers: dsanders, aemerson, aditya_nandakumar
Reviewed By: dsanders
Subscribers: rovka, kristof.beyls, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D53734
llvm-svn: 345875
This was added in r330630. GCC's -Wimplicit-fallthrough seems to not
fire when the previous case contains a switch itself.
This fallthrough was bening because the helper function implementing the
case used dyn_cast to re-check the type of the node in question. After
fixing the fallthrough, we can strengthen the cast.
llvm-svn: 345864
optsize using masked wide loads
Under Opt for Size, the vectorizer does not vectorize interleave-groups that
have gaps at the end of the group (such as a loop that reads only the even
elements: a[2*i]) because that implies that we'll require a scalar epilogue
(which is not allowed under Opt for Size). This patch extends the support for
masked-interleave-groups (introduced by D53011 for conditional accesses) to
also cover the case of gaps in a group of loads; Targets that enable the
masked-interleave-group feature don't have to invalidate interleave-groups of
loads with gaps; they could now use masked wide-loads and shuffles (if that's
what the cost model selects).
Reviewers: Ayal, hsaito, dcaballe, fhahn
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D53668
llvm-svn: 345705
Emit pseudo instructions indicating unwind codes corresponding to each
instruction inside the prologue/epilogue. These are used by the MCLayer to
populate the .xdata section.
Differential Revision: https://reviews.llvm.org/D50288
llvm-svn: 345701
Summary:
Thunk functions in Windows are varag functions that call a musttail function
to pass the arguments after the fixup is done. We need to make sure that we
forward the arguments from the caller vararg to the callee vararg function.
This is the same mechanism that is used for Windows on X86.
Reviewers: ssijaric, eli.friedman, TomTan, mgrang, mstorsjo, rnk, compnerd, efriedma
Reviewed By: efriedma
Subscribers: efriedma, kristof.beyls, chrib, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D53843
llvm-svn: 345641
Prevents the post-RA scheduler from modifying the prologue sequences
emitting by frame lowering. This is roughly similar to what we do for
other targets: TargetInstrInfo::isSchedulingBoundary checks
isPosition(), which checks for CFI_INSTRUCTION.
isSEHInstruction is taken from D50288; it'll land with whatever patch
lands first.
Differential Revision: https://reviews.llvm.org/D53851
llvm-svn: 345634
Re-apply r345315 with testcase fixes.
Include all of the store's source vector operands when creating the
MachineMemOperand. Previously, we were missing the first operand,
making the store size seem smaller than it really is.
Differential Revision: https://reviews.llvm.org/D52816
llvm-svn: 345631
Rename SIMDThreeSameMult (etc.) to SIMDThreeSameVectorFML (etc.) to follow
usual naming convention, and add some comments in the .td files.
llvm-svn: 345515
- Add support to generate AUTIBSP, PACIBSP, RETAB instructions for return
address signing
- The key used to sign the function is controlled by the function attribute
"sign-return-address-key"
Differential Revision: https://reviews.llvm.org/D51427
llvm-svn: 345511
Add ARM64 unwind codes to MCLayer, as well SEH directives that will be emitted
by the frame lowering patch to follow. We only emit unwind codes into object
object files for now.
Differential Revision: https://reviews.llvm.org/D50166
llvm-svn: 345450
Add LLVM intrinsics for the ARMv8.2-A FP16FML vector-form instructions. Add a
DAG pattern to define the indexed-form intrinsics in terms of the vector-form
ones, similarly to how the Dot Product intrinsics were implemented.
Based on a patch by Gao Yiling.
Differential Revision: https://reviews.llvm.org/D53632
llvm-svn: 345337
Include all of the store's source vector operands when creating the
MachineMemOperand. Previously, we were missing the first operand,
making the store size seem smaller than it really is.
Differential Revision: https://reviews.llvm.org/D52816
llvm-svn: 345315
Summary:
Currently, Legalizer is trying to lower G_LOAD with a vector type
that has more than two elements due to the incorrect LegalityPredicate.
This patch fixes the issue by removing the multiplication by 8
as `MemDesc.Size` already contains the size in bits.
Reviewers: dsanders, aemerson
Reviewed By: dsanders
Subscribers: rovka, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D53679
llvm-svn: 345282
If we have a 64-bit EXT where one of the operands is a subvector of a 128-bit
vector then in some cases we can eliminate an extract_subvector by converting
to a 128-bit EXT of the 128-bit vector.
Differential Revision: https://reviews.llvm.org/D53582
llvm-svn: 345275
Using a multiclass reduces duplication, and makes it easier to add new patterns
later. This refactoring does add some new patterns, but as far as I can tell
there's no IR that will end up triggering them so this is effectively NFC.
Differential Revision: https://reviews.llvm.org/D53580
llvm-svn: 345271
Currently a vector move of 0 or -1 will use different instructions depending on
the size of the vector. Using a single instruction (the 128-bit one) for both
gives more opportunity for Machine CSE to eliminate instructions.
Differential Revision: https://reviews.llvm.org/D53579
llvm-svn: 345270
I noticed while fixing PR39368 that we don't have generic shuffle costs for broadcast style shuffles.
This patch adds SK_BROADCAST handling, but exposes ARM/AARCH64 lack of handling of this type, which I've added a fix for at the same time.
Differential Revision: https://reviews.llvm.org/D53570
llvm-svn: 345253
Summary:
Changes all uses of minnan/maxnan to minimum/maximum
globally. These names emphasize that the semantic difference between
these operations is more than just NaN-propagation.
Reviewers: arsenm, aheejin, dschuff, javed.absar
Subscribers: jholewinski, sdardis, wdng, sbc100, jgravelle-google, jrtc27, atanasyan, llvm-commits
Differential Revision: https://reviews.llvm.org/D53112
llvm-svn: 345218
AARCH64 equivalent to D53257 - uses widening pairwise adds on vXi8 CTPOP to support i16/i32/i64 vectors.
This is a blocker for generic vector CTPOP expansion (P32655) - this will remove the aarch64 diff from D53258.
Differential Revision: https://reviews.llvm.org/D53259
llvm-svn: 344554
interleave-group
The vectorizer currently does not attempt to create interleave-groups that
contain predicated loads/stores; predicated strided accesses can currently be
vectorized only using masked gather/scatter or scalarization. This patch makes
predicated loads/stores candidates for forming interleave-groups during the
Loop-Vectorizer's analysis, and adds the proper support for masked-interleave-
groups to the Loop-Vectorizer's planning and transformation stages. The patch
also extends the TTI API to allow querying the cost of masked interleave groups
(which each target can control); Targets that support masked vector loads/
stores may choose to enable this feature and allow vectorizing predicated
strided loads/stores using masked wide loads/stores and shuffles.
Reviewers: Ayal, hsaito, dcaballe, fhahn, javed.absar
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D53011
llvm-svn: 344472
Summary:
AArch64 can fold some shift+extend operations on the RHS operand of
comparisons, so swap the operands if that makes sense.
This provides a fix for https://bugs.llvm.org/show_bug.cgi?id=38751
Reviewers: efriedma, t.p.northover, javed.absar
Subscribers: mcrosier, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D53067
llvm-svn: 344439
The ARM64 elf emitter would omit printing data
symbol for zero filled constant data. This patch
overrides the emitFill method as to enforce that
the symbol is correctly printed.
Differential revision: https://reviews.llvm.org/D53132
llvm-svn: 344248
When branch target identification is enabled, we can only do indirect
tail-calls through x16 or x17. This means that the outliner can't
transform a BLR instruction at the end of an outlined region into a BR.
Differential revision: https://reviews.llvm.org/D52869
llvm-svn: 343969
When branch target identification is enabled, all indirectly-callable
functions start with a BTI C instruction. this instruction can only be
the target of certain indirect branches (direct branches and
fall-through are not affected):
- A BLR instruction, in either a protected or unprotected page.
- A BR instruction in a protected page, using x16 or x17.
- A BR instruction in an unprotected page, using any register.
Without BTI, we can use any non call-preserved register to hold the
address for an indirect tail call. However, when BTI is enabled, then
the code being compiled might be loaded into a BTI-protected page, where
only x16 and x17 can be used for indirect tail calls.
Legacy code withiout this restriction can still indirectly tail-call
BTI-protected functions, because they will be loaded into an unprotected
page, so any register is allowed.
Differential revision: https://reviews.llvm.org/D52868
llvm-svn: 343968
The Branch Target Identification extension, introduced to AArch64 in
Armv8.5-A, adds the BTI instruction, which is used to mark valid targets
of indirect branches. When enabled, the processor will trap if an
instruction in a protected page tries to perform an indirect branch to
any instruction other than a BTI. The BTI instruction uses encodings
which were NOPs in earlier versions of the architecture, so BTI-enabled
code will still run on earlier hardware, just without the extra
protection.
There are 3 variants of the BTI instruction, which are valid targets for
different kinds or branches:
- BTI C can be targeted by call instructions, and is inteneded to be
used at function entry points. These are the BLR instruction, as well
as BR with x16 or x17. These BR instructions are allowed for use in
PLT entries, and we can also use them to allow indirect tail-calls.
- BTI J can be targeted by BR only, and is intended to be used by jump
tables.
- BTI JC acts ab both a BTI C and a BTI J instruction, and can be
targeted by any BLR or BR instruction.
Note that RET instructions are not restricted by branch target
identification, the reason for this is that return addresses can be
protected more effectively using return address signing. Direct branches
and calls are also unaffected, as it is assumed that an attacker cannot
modify executable pages (if they could, they wouldn't need to do a
ROP/JOP attack).
This patch adds a MachineFunctionPass which:
- Adds a BTI C at the start of every function which could be indirectly
called (either because it is address-taken, or externally visible so
could be address-taken in another translation unit).
- Adds a BTI J at the start of every basic block which could be
indirectly branched to. This could be either done by a jump table, or
by taking the address of the block (e.g. the using GCC label values
extension).
We only need to use BTI JC when a function is indirectly-callable, and
takes the address of the entry block. I've not been able to trigger this
from C or IR, but I've included a MIR test just in case.
Using BTI C at function entries relies on the fact that no other code in
BTI-protected pages uses indirect tail-calls, unless they use x16 or x17
to hold the address. I'll add that code-generation restriction as a
separate patch.
Differential revision: https://reviews.llvm.org/D52867
llvm-svn: 343967
The MachineOutliner for AArch64 transforms indirect calls into indirect
tail calls, replacing the call with the TCRETURNri pseudo-instruction.
This pseudo lowers to a BR, but has the isCall and isReturn flags set.
The problem is that TCRETURNri takes a tcGPR64 as the register argument,
to prevent indiret tail-calls from using caller-saved registers. The
indirect calls transformed by the outliner could use caller-saved
registers. This is fine, because the outliner ensures that the register
is available at all call sites. However, this causes a verifier failure
when the register is not in tcGPR64. The fix is to add a new
pseudo-instruction like TCRETURNri, but which accepts any GPR.
Differential revision: https://reviews.llvm.org/D52829
llvm-svn: 343959
This rebases and recommits r343520. hwasan should be fixed now and this
shouldn't break the tests anymore.
Spill/reload instructions are artificially generated by the compiler and
have no relation to the original source code. So the best thing to do is
not attach any debug location to them (instead of just taking the next
debug location we find on following instructions).
Differential Revision: https://reviews.llvm.org/D52125
llvm-svn: 343895
Finally all targets are enabling multiple regalloc hints, so the hook to
disable this can now be removed.
NFC.
Review: Simon Pilgrim
https://reviews.llvm.org/D52316
llvm-svn: 343851
- Fix spill/reloads of XSeqPairs failing with vregs (only physregs
worked correctly)
- Add missing spill/reload code for WSeqPairs class
Differential Revision: https://reviews.llvm.org/D52761
llvm-svn: 343799
Summary: Depends on D45541
Reviewers: ab, aditya_nandakumar, bogner, rtereshin, volkan, rovka, javed.absar, aemerson
Subscribers: aemerson, rengolin, mgorny, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D45543
The previous commit failed portions of the test-suite on GreenDragon due to
duplicate COPY instructions and iterator invalidation. Both issues have now
been fixed. To assist with this, a helper (cloneVirtualRegister) has been added
to MachineRegisterInfo that can be used to get another register that has the same
type and class/bank as an existing one.
llvm-svn: 343654
This adds new instructions to manipluate tagged pointers, and to load
and store the tags associated with memory.
Patch by Pablo Barrio, David Spickett and Oliver Stannard!
Differential revision: https://reviews.llvm.org/D52490
llvm-svn: 343572
This adds new system registers introduced by the Memory Tagging
extension.
Patch by Pablo Barrio!
Differential revision: https://reviews.llvm.org/D52488
llvm-svn: 343571
The Memory Tagging Extension adds system instructions for data cache
maintenance, implemented as new operands to the DC instruction.
Patch by Pablo Barrio!
Differential revision: https://reviews.llvm.org/D52487
llvm-svn: 343570
This adds the memory tagging extension, which is an optional extension
introduced in v8.5A. The new instructions and registers will be added by
subsequent patches.
Patch by Pablo Barrio!
Differential revision: https://reviews.llvm.org/D52486
llvm-svn: 343563
There's a strange assertion on two of the Green Dragon bots that goes away when
this is reverted. The assertion is in RegBankAlloc and if it is this commit then
-verify-machine-instrs should have caught it earlier in the pipeline.
llvm-svn: 343546
Spill/reload instructions are artificially generated by the compiler and
have no relation to the original source code. So the best thing to do is
not attach any debug location to them (instead of just taking the next
debug location we find on following instructions).
Differential Revision: https://reviews.llvm.org/D52125
llvm-svn: 343520
Split the `zcz` feature into specific ones got GP and FP registers, `zcz-gp`
and `zcz-fp`, respectively, while retaining the original feature option to
mean both.
Differential revision: https://reviews.llvm.org/D52621
llvm-svn: 343354
- Add fix so that all code paths that create DWARFContext
with an ObjectFile initialise the target architecture in the context
- Add an assert that the Arch is known in the Dwarf CallFrameString method
llvm-svn: 343317
Bits [23-22] are used in Add and Sub to specify the shift. The value of the
shift field must be 0x; values of 1x are unallocated. MTE adds some instructions
that use such encodings, and this patch refactors the Add/Sub class so that
another class could derive from this one to implement other encodings and other
formats of bitfields.
Patch by Pablo Barrio!
Differential revision: https://reviews.llvm.org/D52489
llvm-svn: 343231
This adds two new barrier instructions which can be used to restrict
speculative execution of load instructions.
Patch by Pablo Barrio!
Differential revision: https://reviews.llvm.org/D52483
llvm-svn: 343229
This adds new instructions used by the Branch Target Identification
feature. When this is enabled, these are the only instructions which can
be targeted by indirect branch instructions.
Patch by Pablo Barrio!
Differential revision: https://reviews.llvm.org/D52485
llvm-svn: 343225
This adds some new system registers which can be used to restrict
certain types of speculative execution.
Patch by Pablo Barrio and David Spickett!
Differential revision: https://reviews.llvm.org/D52482
llvm-svn: 343218
This adds two new system registers, used to generate random numbers.
This is an optional extension to v8.5-A, and will be controlled by the
"+rng" modifier of the -march= and -mcpu= options.
Patch by Pablo Barrio!
Differential revision: https://reviews.llvm.org/D52481
llvm-svn: 343217
This adds a new variant of the DC system instruction for persistent
memory.
Patch by Pablo Barrio!
Differential revision: https://reviews.llvm.org/D52480
llvm-svn: 343216
This adds new system instructions which act as barriers to speculative
execution based on earlier execution within a particular execution
context.
Patch by Pablo Barrio!
Differential revision: https://reviews.llvm.org/D52479
llvm-svn: 343214
This is a new barrier which limits speculative execution of the
instructions following it.
Patch by Pablo Barrio!
Differential revision: https://reviews.llvm.org/D52476
llvm-svn: 343211
These are some new variants of the "Floating-point Round to Integral"
family of instructions, which round to the nearest floating-point value
which fits in a 32- or 64-bit integer.
Patch by Pablo Barrio!
Differential revision: https://reviews.llvm.org/D52475
llvm-svn: 343209
These new instructions manipluate the NZCV bits, to convert between the
regular Arm floating-point comare format and an alternative format.
Patch by Pablo Barrio!
Differential revision: https://reviews.llvm.org/D52473
llvm-svn: 343187
The Armv8.3-A reference manual defines floating-point data-processing
instructions with one source operand to have an opcode of 6 bits
[20:15]. The current class in tablegen, BaseSingleOperandFPData, only
allows [18:15]. This was ok because [20:19] could only be '00', with
other encodings unallocated. Armv8.5-A brings in the FRINT group of
instructions which use other values for these bits.
This patch refactors the existing class a bit to allow using the full 6
bits of the opcode, as defined in the Arm ARM.
Patch by Pablo Barrio!
Differential revision: https://reviews.llvm.org/D52474
llvm-svn: 343120
Reuse some code in preparation for the v8.5A XAFlag/AXFlag instructions,
which shares part of the encoding of the MSR-immediate.
Patch by Pablo Barrio!
Differential revision: https://reviews.llvm.org/D52472
llvm-svn: 343113
Parsing of the system instructions (IC, DC, AT and TLBI) uses this
function to show the required architecture when the operand is valid,
but the architecture is not enabled. Armv8.5A adds a few different
system instructions as part of optional features, so we need to extend
it to show individual features, not just base architectures.
This is NFC for now, but will be used by three different features added
in v8.5A, and will be tested by them.
Patch by David Spickett!
Differential revision: https://reviews.llvm.org/D52478
llvm-svn: 343109
This caused the DebugInfo/Sparc/gnu-window-save.ll test to fail.
> Functions that have signed return addresses need additional dwarf support:
> - After signing the LR, and before authenticating it, the LR register is in a
> state the is unusable by a debugger or unwinder
> - To account for this a new directive, .cfi_negate_ra_state, is added
> - This directive says the signed state of the LR register has now changed,
> i.e. unsigned -> signed or signed -> unsigned
> - This directive has the same CFA code as the SPARC directive GNU_window_save
> (0x2d), adding a macro to account for multiply defined codes
> - This patch matches the gcc implementation of this support:
> https://patchwork.ozlabs.org/patch/800271/
>
> Differential Revision: https://reviews.llvm.org/D50136
llvm-svn: 343103
This patch allows targeting Armv8.5-A, adding the architecture to
tablegen and setting the options to be identical to Armv8.4-A for the
time being. Subsequent patches will add support for the different
features included in the Armv8.5-A Reference Manual.
Patch by Pablo Barrio!
Differential revision: https://reviews.llvm.org/D52470
llvm-svn: 343102
Functions that have signed return addresses need additional dwarf support:
- After signing the LR, and before authenticating it, the LR register is in a
state the is unusable by a debugger or unwinder
- To account for this a new directive, .cfi_negate_ra_state, is added
- This directive says the signed state of the LR register has now changed,
i.e. unsigned -> signed or signed -> unsigned
- This directive has the same CFA code as the SPARC directive GNU_window_save
(0x2d), adding a macro to account for multiply defined codes
- This patch matches the gcc implementation of this support:
https://patchwork.ozlabs.org/patch/800271/
Differential Revision: https://reviews.llvm.org/D50136
llvm-svn: 343089
Share predecessor search bookkeeping in both perform PostLD1Combine
and performNEONPostLDSTCombine. This should be approximately a 4x and
2x performance improvement.
llvm-svn: 342986
Summary:
Specifying X[8-15,18] registers as callee-saved is used to support
CONFIG_ARM64_LSE_ATOMICS in Linux kernel. As part of this patch we:
- use custom CSR list/mask when user specifies custom CSRs
- update Machine Register Info's list of CSRs with additional custom CSRs in
LowerCall and LowerFormalArguments.
Reviewers: srhines, nickdesaulniers, efriedma, javed.absar
Reviewed By: nickdesaulniers
Subscribers: kristof.beyls, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D52216
llvm-svn: 342824
This involves changing the shouldExpandAtomicCmpXchgInIR interface, but I have
updated the in-tree backends using this hook (ARM, AArch64, Hexagon) so they
will see no functional change. Previously this hook returned bool, but it now
returns AtomicExpansionKind.
This hook allows targets to select how a given cmpxchg is to be expanded.
D48131 uses this to expand part-word cmpxchg to a target-specific intrinsic.
See my associated RFC for more info on the motivation for this change
<http://lists.llvm.org/pipermail/llvm-dev/2018-June/123993.html>.
Differential Revision: https://reviews.llvm.org/D48130
llvm-svn: 342550
This tries to make use of evaluateAsRelocatable in AArch64AsmParser::classifySymbolRef
to parse more complex expressions as relocatable operands. It is hopefully better than
the existing code which only handles Symbol +- Constant.
This allows us to parse more complex adr/adrp, mov, ldr/str and add operands. It also
loosens the requirements on parsing addends in ld/st and mov's and adds a number of
tests.
Differential Revision: https://reviews.llvm.org/D51792
llvm-svn: 342455
This patch adds codegen support for the saving/restoring
V8-V23 for functions specified with the aarch64_vector_pcs
calling convention attribute, as added in patch D51477.
Reviewers: t.p.northover, gberry, thegameg, rengolin, javed.absar, MatzeB
Reviewed By: thegameg
Differential Revision: https://reviews.llvm.org/D51479
llvm-svn: 342049
This patch refactors several parts of AArch64FrameLowering
so that it can be easily extended to support saving/restoring
of FPR128 (Q) registers.
Reviewers: t.p.northover, gberry, thegameg, rengolin, javed.absar
Reviewed By: thegameg
Differential Revision: https://reviews.llvm.org/D51478
llvm-svn: 342038
This patch adds parsing support for the 'aarch64_vector_pcs'
calling convention attribute to calls and function declarations.
More information describing the vector ABI and procedure call standard
can be found here:
https://developer.arm.com/products/software-development-tools/\
hpc/arm-compiler-for-hpc/vector-function-abi
Reviewers: t.p.northover, rnk, rengolin, javed.absar, thegameg, SjoerdMeijer
Reviewed By: SjoerdMeijer
Differential Revision: https://reviews.llvm.org/D51477
llvm-svn: 342030
The was previously committed as r341749 then reverted as r341750 because
bit_cast needed to do its own thing to check is_trivially_copyable on GCC 4.x.
This is now done and std;:array should now get accepted.
llvm-svn: 341897
Disassemblers cannot depend on main target headers. The same is true for
MCTargetDesc, but there's a lot more cleanup needed for that.
llvm-svn: 341822
Summary: I saw a few places that were punning through a union of FP and integer, and that made me sad. Luckily, C++20 adds bit_cast for exactly that purpose. Implement our own version in ADT (without constexpr, leaving us a bit sad), and use it in the few places my grep-fu found silly union punning.
This was originally committed as r341728 and reverted in r341730.
Reviewers: javed.absar, steven_wu, srhines
Subscribers: dexonsmith, llvm-commits
Differential Revision: https://reviews.llvm.org/D51693
llvm-svn: 341741
Summary: I saw a few places that were punning through a union of FP and integer, and that made me sad. Luckily, C++20 adds bit_cast for exactly that purpose. Implement our own version in ADT (without constexpr, leaving us a bit sad), and use it in the few places my grep-fu found silly union punning.
Reviewers: javed.absar
Subscribers: dexonsmith, llvm-commits
Differential Revision: https://reviews.llvm.org/D51693
llvm-svn: 341728
Summary:
Reserving registers x1-7 is used to support CONFIG_ARM64_LSE_ATOMICS in Linux kernel. This change adds support for reserving registers x1 through x7.
Reviewers: javed.absar, phosek, srhines, nickdesaulniers, efriedma
Reviewed By: nickdesaulniers, efriedma
Subscribers: niravd, jfb, manojgupta, nickdesaulniers, jyknight, efriedma, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D48580
llvm-svn: 341706
Summary:
I added a few ARM64 memset codegen tests in r341406 and r341493, and annotated
where the generated code was bad. This patch fixes the majority of the issues by
requesting that a 2xi64 vector be used for memset of 32 bytes and above.
The patch leaves the former request for f128 unchanged, despite f128
materialization being suboptimal: doing otherwise runs into other asserts in
isel and makes this patch too broad.
This patch hides the issue that was present in bzero_40_stack and bzero_72_stack
because the code now generates in a better order which doesn't have the store
offset issue. I'm not aware of that issue appearing elsewhere at the moment.
<rdar://problem/44157755>
Reviewers: t.p.northover, MatzeB, javed.absar
Subscribers: eraman, kristof.beyls, chrib, dexonsmith, llvm-commits
Differential Revision: https://reviews.llvm.org/D51706
llvm-svn: 341558
On Windows, if shouldAssumeDSOLocal returns false, it's either a
dllimport reference, or a reference that we should treat as non-local
and create a stub for.
Clean up AArch64Subtarget::ClassifyGlobalReference a little while
touching the flag handling relating to dllimport.
Differential Revision: https://reviews.llvm.org/D51590
llvm-svn: 341402
The runtime pseudo relocations can't handle the AArch64 format PC
relative addressing in adrp+add/ldr pairs. By using stubs, the potentially
dllimported addresses can be touched up by the runtime pseudo relocation
framework.
Differential Revision: https://reviews.llvm.org/D51452
llvm-svn: 341401
When initial support for dllimport was added for aarch64 in
SVN r316555, ClassifyGlobalReference didn't set the MO_DLLIMPORT
flag - that was only completed in SVN r323810. Reuse the return
value from ClassifyGlobalReference for this purpose as well.
llvm-svn: 341310
Summary:
This is a continuation of https://reviews.llvm.org/D49727
Below the original text, current changes in the comments:
Currently, in line with GCC, when specifying reserved registers like sp or pc on an inline asm() clobber list, we don't always preserve the original value across the statement. And in general, overwriting reserved registers can have surprising results.
For example:
extern int bar(int[]);
int foo(int i) {
int a[i]; // VLA
asm volatile(
"mov r7, #1"
:
:
: "r7"
);
return 1 + bar(a);
}
Compiled for thumb, this gives:
$ clang --target=arm-arm-none-eabi -march=armv7a -c test.c -o - -S -O1 -mthumb
...
foo:
.fnstart
@ %bb.0: @ %entry
.save {r4, r5, r6, r7, lr}
push {r4, r5, r6, r7, lr}
.setfp r7, sp, #12
add r7, sp, #12
.pad #4
sub sp, #4
movs r1, #7
add.w r0, r1, r0, lsl #2
bic r0, r0, #7
sub.w r0, sp, r0
mov sp, r0
@APP
mov.w r7, #1
@NO_APP
bl bar
adds r0, #1
sub.w r4, r7, #12
mov sp, r4
pop {r4, r5, r6, r7, pc}
...
r7 is used as the frame pointer for thumb targets, and this function needs to restore the SP from the FP because of the variable-length stack allocation a. r7 is clobbered by the inline assembly (and r7 is included in the clobber list), but LLVM does not preserve the value of the frame pointer across the assembly block.
This type of behavior is similar to GCC's and has been discussed on the bugtracker: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=11807 . No consensus seemed to have been reached on the way forward. Clang behavior has briefly been discussed on the CFE mailing (starting here: http://lists.llvm.org/pipermail/cfe-dev/2018-July/058392.html). I've opted for following Eli Friedman's advice to print warnings when there are reserved registers on the clobber list so as not to diverge from GCC behavior for now.
The patch uses MachineRegisterInfo's target-specific knowledge of reserved registers, just before we convert the inline asm string in the AsmPrinter.
If we find a reserved register, we print a warning:
repro.c:6:7: warning: inline asm clobber list contains reserved registers: R7 [-Winline-asm]
"mov r7, #1"
^
Reviewers: efriedma, olista01, javed.absar
Reviewed By: efriedma
Subscribers: eraman, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D51165
llvm-svn: 341062
Providing that the load is known to be 4 byte aligned, we can optimise a
ldr(adr address) to just ldr address.
Differential Revision: https://reviews.llvm.org/D51030
llvm-svn: 341058
This adds a new method to ELFObjectFileBase that returns the symbols and addresses of PLT entries.
This design was suggested by pcc and eugenis in https://reviews.llvm.org/D49383.
Differential Revision: https://reviews.llvm.org/D50203
llvm-svn: 340610
This adds the plumbing for the Tiny code model for the AArch64 backend. This,
instead of loading addresses through the normal ADRP;ADD pair used in the Small
model, uses a single ADR. The 21 bit range of an ADR means that the code and
its statically defined symbols need to be within 1MB of each other.
This makes it mostly interesting for embedded applications where we want to fit
as much as we can in as small a space as possible.
Differential Revision: https://reviews.llvm.org/D49673
llvm-svn: 340397
Summary: When run under llvm-mc-disassemble-fuzzer, there is no symbol lookup callback so tryAddingSymbolicOperand() must fail gracefully instead of crashing
Reviewers: aemerson, javed.absar
Reviewed By: aemerson
Subscribers: lhames, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D51005
llvm-svn: 340287
This patch adds system registers for controlling aspects of SVE:
- ZCR_EL1 (r/w) visible at EL1 and EL0.
- ZCR_EL2 (r/w) visible at EL2 and Non-secure EL1 and EL0.
- ZCR_EL3 (r/w) visible at all exception levels.
and a system register identifying SVE:
- ID_AA64ZFR0_EL1 (r) SVE Feature identifier.
Reviewers: SjoerdMeijer, samparker, pbarrio, fhahn, javed.absar
Reviewed By: SjoerdMeijer
Differential Revision: https://reviews.llvm.org/D50885
llvm-svn: 340158
- Generate pointer authentication instructions
- The functions instrumented depend on function attribtues:
all (all functions instrumentent)
non-leaf (only those that spill LR)
none
- Function epilogues sign the LR before spilling to the stack and authenticate
the LR once restored
- If the target is v8.3a or greater than can use the combined authenticate and
return instruction
Differential revision: https://reviews.llvm.org/D49793
llvm-svn: 340018
Add +fp16fml feature for new FP16 instructions, which are a
mandatory part of FP16 from v8.4-A and an optional part of FP16
from v8.2-A. It doesn't seem to be possible to model this in
LLVM, but the relationship between the options is handled by
the related clang patch.
In keeping with what I think is the usual practice, the fp16fml
extension is accepted regardless of base architecture version.
Builds on/replaces Sjoerd Meijer's patch to add these instructions at
https://reviews.llvm.org/D49839.
Differential Revision: https://reviews.llvm.org/D50228
llvm-svn: 340013
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
`MachineMemOperand` pointers attached to `MachineSDNodes` and instead
have the `SelectionDAG` fully manage the memory for this array.
Prior to this change, the memory management was deeply confusing here --
The way the MI was built relied on the `SelectionDAG` allocating memory
for these arrays of pointers using the `MachineFunction`'s allocator so
that the raw pointer to the array could be blindly copied into an
eventual `MachineInstr`. This creates a hard coupling between how
`MachineInstr`s allocate their array of `MachineMemOperand` pointers and
how the `MachineSDNode` does.
This change is motivated in large part by a change I am making to how
`MachineFunction` allocates these pointers, but it seems like a layering
improvement as well.
This would run the risk of increasing allocations overall, but I've
implemented an optimization that should avoid that by storing a single
`MachineMemOperand` pointer directly instead of allocating anything.
This is expected to be a net win because the vast majority of uses of
these only need a single pointer.
As a side-effect, this makes the API for updating a `MachineSDNode` and
a `MachineInstr` reasonably different which seems nice to avoid
unexpected coupling of these two layers. We can map between them, but we
shouldn't be *surprised* at where that occurs. =]
Differential Revision: https://reviews.llvm.org/D50680
llvm-svn: 339740
Intentionally excluding nodes from the DAGCombine worklist is likely to
lead to weird optimizations and infinite loops, so it's generally a bad
idea.
To avoid the infinite loops, fix DAGCombine to use the
isDesirableToCommuteWithShift target hook before performing the
transforms in question, and implement the target hook in the ARM backend
disable the transforms in question.
Fixes https://bugs.llvm.org/show_bug.cgi?id=38530 . (I don't have a
reduced testcase for that bug. But we should have sufficient test
coverage for PerformSHLSimplify given that we're not playing weird
tricks with the worklist. I can try to bugpoint it if necessary,
though.)
Differential Revision: https://reviews.llvm.org/D50667
llvm-svn: 339734
Summary:
Ensure that NormalizedBuildVector returns a BUILD_VECTOR with operands of the
same type. This fixes an assertion failure in VerifySDNode.
Reviewers: SjoerdMeijer, t.p.northover, javed.absar
Reviewed By: SjoerdMeijer
Subscribers: kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D50202
llvm-svn: 339013
As a part of adding the tiny codemodel, we need to support ldr's with :got:
relocations on them. This seems to be mostly already done, just needs the
relocation type support.
Differential Revision: https://reviews.llvm.org/D50137
llvm-svn: 338673
AArch64 ELF ABI does not define a static relocation type for TLS offset within
a module, which makes it impossible for compiler to generate a valid
DW_AT_location content for thread local variables. Currently LLVM generates an
invalid R_AARCH64_ABS64 relocation at the DW_AT_location field for a TLS
variable. That causes trouble for linker because thread local variable does
not have an absolute address at link time. AArch64 GCC solves the problem by
not generating DW_AT_location for thread local variables. We should do the
same in LLVM.
Differential Revision: https://reviews.llvm.org/D43860
llvm-svn: 338655
Contrary to ELF, we don't add any markers that distinguish data generated
with .long from normal instructions, so the .inst directive only adds
compatibility with assembly that uses it.
Differential Revision: https://reviews.llvm.org/D49935
llvm-svn: 338355
Also refactors some existing code to materialize addresses for the large code
model so it can be shared between G_GLOBAL_VALUE and G_BLOCK_ADDR.
This implements PR36390.
Differential Revision: https://reviews.llvm.org/D49903
llvm-svn: 338337
The vector contains the SDNodes that these functions create. The number of nodes is always a small number so we should use SmallVector to avoid a heap allocation.
llvm-svn: 338329