Avoids using a plain unsigned for registers throughoug codegen.
Doesn't attempt to change every register use, just something a little
more than the set needed to build after changing the return type of
MachineOperand::getReg().
llvm-svn: 364191
As discussed on D62910, we need to check whether particular types of memory access are allowed, not just their alignment/address-space.
This NFC patch adds a MachineMemOperand::Flags argument to allowsMemoryAccess and allowsMisalignedMemoryAccesses, and wires up calls to pass the relevant flags to them.
If people are happy with this approach I can then update X86TargetLowering::allowsMisalignedMemoryAccesses to handle misaligned NT load/stores.
Differential Revision: https://reviews.llvm.org/D63075
llvm-svn: 363179
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
Make sure to not unroll a vector division/remainder (with a constant splat
divisor) after type legalization, since the scalar type may then be illegal.
Review: Ulrich Weigand
https://reviews.llvm.org/D62036
llvm-svn: 360965
This allows better code size for aarch64 floating point materialization
in a future patch.
Reviewers: evandro
Differential Revision: https://reviews.llvm.org/D58690
llvm-svn: 356389
Summary:
The description of KnownBits::zext() and
KnownBits::zextOrTrunc() has confusingly been telling
that the operation is equivalent to zero extending the
value we're tracking. That has not been true, instead
the user has been forced to explicitly set the extended
bits as known zero afterwards.
This patch adds a second argument to KnownBits::zext()
and KnownBits::zextOrTrunc() to control if the extended
bits should be considered as known zero or as unknown.
Reviewers: craig.topper, RKSimon
Reviewed By: RKSimon
Subscribers: javed.absar, hiraditya, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58650
llvm-svn: 355099
At the moment, we mark every atomic memory access as being also volatile. This is unnecessarily conservative and prohibits many legal transforms (DCE, folding, etc..).
This patch removes MOVolatile from the MachineMemOperands of atomic, but not volatile, instructions. This should be strictly NFC after a series of previous patches which have gone in to ensure backend code is conservative about handling of isAtomic MMOs. Once it's in and baked for a bit, we'll start working through removing unnecessary bailouts one by one. We applied this same strategy to the middle end a few years ago, with good success.
To make sure this patch itself is NFC, it is build on top of a series of other patches which adjust code to (for the moment) be as conservative for an atomic access as for a volatile access and build up a test corpus (mostly in test/CodeGen/X86/atomics-unordered.ll)..
Previously landed
D57593 Fix a bug in the definition of isUnordered on MachineMemOperand
D57596 [CodeGen] Be conservative about atomic accesses as for volatile
D57802 Be conservative about unordered accesses for the moment
rL353959: [Tests] First batch of cornercase tests for unordered atomics.
rL353966: [Tests] RMW folding tests w/unordered atomic operations.
rL353972: [Tests] More unordered atomic lowering tests.
rL353989: [SelectionDAG] Inline a single use helper function, and remove last non-MMO interface
rL354740: [Hexagon, SystemZ] Be super conservative about atomics
rL354800: [Lanai] Be super conservative about atomics
rL354845: [ARM] Be super conservative about atomics
Attention Out of Tree Backend Owners: This patch may break you. If it does, you can use the TLI getMMOFlags hook to restore the MOVolatile to any instruction you need to. (See llvm-dev thread titled "PSA: Changes to how atomics are handled in backends" started Feb 27, 2019.)
Differential Revision: https://reviews.llvm.org/D57601
llvm-svn: 355025
This patch aims to make sure that any such constant that can be generated
with a vector instruction (for example VGBM) is recognized as such during
legalization and kept as a target independent node through post-legalize
DAGCombining.
Two new functions named isVectorConstantLegal() and loadVectorConstant()
replace old ways of handling vector/FP constants.
A new struct named SystemZVectorConstantInfo is used to cache the results of
isVectorConstantLegal() and pass them onto loadVectorConstant().
Support for fp128 constants in the presence of FeatureVectorEnhancements1
(z14) has been added.
Review: Ulrich Weigand
https://reviews.llvm.org/D58270
llvm-svn: 354896
It seems there were some problem with using a .mir test. For some reason
doing '-stop-before=codegenprepare' and then '-start-before=codegenprepare'
on the output .mir file results in the NoVRegs Property after instruction
selection.
Recommitting the same test as an .ll file instead.
llvm-svn: 354160
isFPImmLegal() has been extended to recognize certain FP immediates that can
be built with VGM (Vector Generate Mask).
These scalar FP immediates (that were previously loaded from the constant
pool) are now selected as VGMF/VGMG in Select().
Review: Ulrich Weigand
https://reviews.llvm.org/D58003
llvm-svn: 353867
Since SystemZ supports counting of leading zeros with the FLOGR instruction,
isCheapToSpeculateCtlz() should return true, which it now does.
ISD::CTLZ_ZERO_UNDEF i32 is now handled the same way as ISD::CTLZ is, which
is needed since promotion to i64 is required and CTLZ_ZERO_UNDEF is only
expanded to CTLZ if it is Legal or Custom.
Review: Ulrich Weigand
https://reviews.llvm.org/D57710
llvm-svn: 353330
Don't lower BUILD_VECTORs to BYTE_MASK, but instead expose the BUILD_VECTORs
to the DAGCombiner and select them to VGBM in Select(). This allows the
DAGCombiner to understand the constant vector values.
For floating point, only all-zeros vectors are now generated with VGBM, as it
turned out to be somewhat complicated to handle any arbitrary constants,
while in practice this is very rare and hardly needed.
The SystemZ ISD opcodes z_byte_mask, z_vzero and z_vones have been removed.
Review: Ulrich Weigand
https://reviews.llvm.org/D57152
llvm-svn: 353325
The IPM sequence currently generated to compute the strcmp/memcmp
result will return INT_MIN for the "less than zero" case. While
this is in compliance with the standard, strictly speaking, it
turns out that common applications cannot handle this, e.g. because
they negate a comparison result in order to implement reverse
compares.
This patch changes code to use a different sequence that will result
in -2 for the "less than zero" case (same as GCC). However, this
requires that the two source operands of the compare instructions
are inverted, which breaks the optimization in removeIPMBasedCompare.
Therefore, I've removed this (and all of optimizeCompareInstr), and
replaced it with a mostly equivalent optimization in combineCCMask
at the DAGcombine level.
llvm-svn: 353304
Summary:
Like with X86, this allows better DAG-level alias analysis and
alignment inference for wrapped addresses.
Reviewers: jonpa, uweigand
Reviewed By: uweigand
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D57407
llvm-svn: 352786
After creating new PHI instructions during isel pseudo expansion, the NoPHIs
property of MF should be reset in case it was previously set.
Review: Ulrich Weigand
llvm-svn: 352030
Two backend optimizations failed to handle cases when compiled with -g, due
to failing to consider DBG_VALUE instructions. This was in
SystemZTargetLowering::emitSelect() and
SystemZElimCompare::getRegReferences().
This patch makes sure that DBG_VALUEs are recognized so that they do not
affect these optimizations.
Tests for branch-on-count, load-and-trap and consecutive selects.
Review: Ulrich Weigand
https://reviews.llvm.org/D57048
llvm-svn: 351928
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
We already have special code (DAG combine support for FP_ROUND)
to recognize cases where we an use a vector version of VLEDB to
perform two floating-point truncates in parallel, but equivalent
support for VLEDB (vector floating-point extends) has been
missing so far. This patch adds corresponding DAG combine
support for FP_EXTEND.
llvm-svn: 349746
If a loaded value is replicated it is best to combine these two operations
into a VLREP (load and replicate), but isel will not produce this if the load
has other users as well.
This patch handles this by putting the other users of the load to use the
REPLICATE 0-element instead of the load. This way the load has only the
REPLICATE node as user, and we get a VLREP.
Review: Ulrich Weigand
https://reviews.llvm.org/D54264
llvm-svn: 346746
Iterate over all elements and count the number of uses among them for each
used load. Then make sure to REPLICATE the load which has the most uses in
order to minimize the number of needed element insertions.
Review: Ulrich Weigand
https://reviews.llvm.org/D54322
llvm-svn: 346637
A minor improvement of buildVector() that skips creating an
INSERT_VECTOR_ELT for a Value which has already been used for the
REPLICATE.
Review: Ulrich Weigand
https://reviews.llvm.org/D54315
llvm-svn: 346504
The LRV and STRV nodes carry an extra operand to indicate the
type of the memory access. This is redundant, since the nodes
are actually of class MemIntrinsicNode and therefore hold that
same information already as MemoryVT.
NFC intended.
llvm-svn: 345618
Enable the DAG optimization that converts vector div/rem with constants into
multiply+shifts sequences by expanding them early. This is needed since
ISD::SMUL_LOHI is 'Custom' lowered on SystemZ, and will therefore not be
available to BuildSDIV after legalization.
Better cost values for these instructions based on how they will be
implemented (a constant divisor is cheaper).
Review: Ulrich Weigand
https://reviews.llvm.org/D53196
llvm-svn: 345321
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
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
Change
subreg_r32 -> subreg_h32
subreg_r64 -> subreg_h64
subreg_hr32 -> subreg_hh32
The subregisters subreg_r32 and subreg_r64 were added to emphasize the
fact that modifying these subregisters may clobber the entire register.
This is not necessarily the case for subreg_h32, et al.
However, the ability to compose subreg_h64 with subreg_r32, and with
subreg_h32 and subreg_l32 at the same time makes the compositions be
treated as non-overlapping (leading to problems when tracking subreg
liveness). See D50468 for more details.
Differential Revision: https://reviews.llvm.org/D50725
llvm-svn: 339778
The DAG combiner logic to simplify AND masks in shift counts is invalid.
While it is true that the SystemZ shift instructions ignore all but the
low 6 bits of the shift count, it is still invalid to simplify the AND
masks while the DAG still uses the standard shift operators (which are
*not* defined to match the SystemZ instruction behavior).
Instead, this patch performs equivalent operations during instruction
selection. For completely removing the AND, this now happens via
additional DAG match patterns implemented by a multi-alternative
PatFrags. For simplifying a 32-bit AND to a 16-bit AND, the existing DAG
patterns were already mostly OK, they just needed an output XForm to
actually truncate the immediate value.
Unfortunately, the latter change also exposed a bug in TableGen: it
seems XForms are currently only handled correctly for direct operands of
the outermost operation node. This patch also fixes that bug by simply
recurring through the whole pattern. This should be NFC for all other
targets.
Differential Revision: https://reviews.llvm.org/D50096
llvm-svn: 338521
If we are only extracting vector elements via EXTRACT_VECTOR_ELT(s) we may be able to use SimplifyDemandedVectorElts to avoid unnecessary vector ops.
Differential Revision: https://reviews.llvm.org/D49262
llvm-svn: 337258
Inspired by r331508, I did a grep and found these.
Mostly just change from dyn_cast to cast. Some cases also showed a dyn_cast result being converted to bool, so those I changed to isa.
llvm-svn: 331577
This provides an optimized implementation of SADDO/SSUBO/UADDO/USUBO
as well as ADDCARRY/SUBCARRY on top of the new CC implementation.
In particular, multi-word arithmetic now uses UADDO/ADDCARRY instead
of the old ADDC/ADDE logic, which means we no longer need to use
"glue" links for those instructions. This also allows making full
use of the memory-based instructions like ALSI, which couldn't be
recognized due to limitations in the DAG matcher previously.
Also, the llvm.sadd.with.overflow et.al. intrinsincs now expand to
directly using the ADD instructions and checking for a CC 3 result.
llvm-svn: 331203
Currently, an instruction setting the condition code is linked to
the instruction using the condition code via a "glue" link in the
SelectionDAG. This has a number of drawbacks; in particular, it
means the same CC cannot be used by multiple users. It also makes
it more difficult to efficiently implement SADDO et. al.
This patch changes the back-end to represent CC dependencies as
normal values during SelectionDAG matching, along the lines of
how this is handled in the X86 back-end already.
In addition to the core mechanics of updating all relevant patterns,
this requires a number of additional changes:
- We now need to be able to spill/restore a CC value into a GPR
if necessary. This means providing a copyPhysReg implementation
for moves involving CC, and defining getCrossCopyRegClass.
- Since we still prefer to avoid such spills, we provide an override
for IsProfitableToFold to avoid creating a merged LOAD / ICMP if
this would result in multiple users of the CC.
- combineCCMask no longer requires a single CC user, and no longer
need to be careful about preventing invalid glue/chain cycles.
- emitSelect needs to be more careful in marking CC live-in to
the basic block it generates. Also, we can now optimize the
case of multiple subsequent selects with the same condition
just like X86 does.
llvm-svn: 331202
If we have LOCR instructions, select them directly from SelectionDAG
instead of first going through a pseudo instruction and then using
the custom inserter to emit the LOCR.
Provide Select pseudo-instructions for VR32/VR64 if we have vector
instructions, to avoid having to go through the first 16 FPRs
unnecessarily.
If we do not have LOCFHR, prefer using LOCR followed by a move
over a conditional branch.
llvm-svn: 331191
While not necessary for correctness, it is preferable for
performance reasons on all architectures we currently support
to align functions to 16-byte boundaries by default.
llvm-svn: 330718
If DoneMBB becomes empty it must have CC added to its live-in list, since it
will fall-through into EndMBB. This happens when the CLC loop does the
complete range.
Review: Ulrich Weigand
llvm-svn: 327834
Improve/implement these methods to improve DAG combining. This mainly
concerns intrinsics.
Some constant operands to SystemZISD nodes have been marked Opaque to avoid
transforming back and forth between generic and target nodes infinitely.
Review: Ulrich Weigand
llvm-svn: 327765
The byte-swapping loads and stores do not actually perform multiple
accesses to their memory operand, so they are OK to use with volatile
memory operands as well. Remove overly cautious check.
llvm-svn: 326613
This adds support for specifying vector registers for use with inline
asm statements, either via the 'v' constraint or by explicit register
names (v0 ... v31).
llvm-svn: 326609
Emulated TLS is enabled by llc flag -emulated-tls,
which is passed by clang driver.
When llc is called explicitly or from other drivers like LTO,
missing -emulated-tls flag would generate wrong TLS code for targets
that supports only this mode.
Now use useEmulatedTLS() instead of Options.EmulatedTLS to decide whether
emulated TLS code should be generated.
Unit tests are modified to run with and without the -emulated-tls flag.
Differential Revision: https://reviews.llvm.org/D42999
llvm-svn: 326341
Since these methods will assert if the integer does not fit into 64 bits,
it is necessary to do this check before calling them in
supportedAddressingMode().
Review: Ulrich Weigand.
llvm-svn: 323866
The change in r322988 caused a failure in the bootstrap build bot.
The problem was that directly gluing a BR_CCMASK node to a
compare-and-swap could lead to issues if other nodes were
chained in between. There is then no way to create a topological
sort that respects both the chain sequence and the glue property.
Fixed for now by rejecting the optimization in this case. As a
future enhancement, we may be able to handle additional cases
by swapping chain links around.
llvm-svn: 323129
In order to implement a test whether a compare-and-swap succeeded, the
SystemZ back-end currently emits a rather inefficient sequence of first
converting the CC result into an integer, and then testing that integer
against zero. This commit changes the back-end to simply directly test
the CC value set by the compare-and-swap instruction.
llvm-svn: 322988
The SystemZ back-end uses a sequence of IPM followed by arithmetic
operations to implement the SETCC primitive. This is currently done
early during SelectionDAG. This patch moves generating those sequences
to much later in SelectionDAG (during PreprocessISelDAG).
This doesn't change much in generated code by itself, but it allows
further enhancements that will be checked-in as follow-on commits.
llvm-svn: 322987
When folding a shift into a test-under-mask comparison, make sure that
there is no loss of precision when creating the shifted comparison
value. This usually never happens, except for certain always-true
comparisons in unoptimized code.
Fixes PR35529.
llvm-svn: 319818
Csmith generated a program where a store after load to the same address did
not get chained after the new load created during DAG legalizing, and so
performed an illegal overwrite of the expected value.
When the new zero-extending load is created, the chain users of the original
load must be updated, which was not done previously.
A similar case was also found and handled in lowerBITCAST.
Review: Ulrich Weigand
https://reviews.llvm.org/D40542
llvm-svn: 319409
The expensive-checks build bot found a problem with the r314428 commit:
if CC is live after a ATOMIC_CMP_SWAPW instruction, it needs to be
marked as live-in to the block after the loop the pseudo gets expanded
to. This actually fixes a code-gen bug as well, since if the CC isn't
live, the CR and JLH are merged to a CRJLH which doesn't actually set
the condition code any more.
llvm-svn: 314465
The SystemZ compare-and-swap instructions already provide the "success"
indication via a condition-code value, so the default expansion of those
operations generates an unnecessary extra comparsion.
llvm-svn: 314428
SystemZTargetLowering::combineSTORE contains code to transform a
combination of STORE + BSWAP into a STRV type instruction.
This transformation is correct for regular stores, but not for
truncating stores. The routine neglected to check for that case.
Fixes a miscompilation of llvm-objcopy with clang, which caused
test suite failures in the SystemZ multistage build bot.
llvm-svn: 313669
isLegalAddressingMode() has recently gained the extra optional Instruction*
parameter, and therefore it can now do the job that previously only
isFoldableMemAccess() could do.
The SystemZ implementation of isLegalAddressingMode() has gained the
functionality of checking for offsets, which used to be done with
isFoldableMemAccess().
The isFoldableMemAccess() hook has been removed everywhere.
Review: Quentin Colombet, Ulrich Weigand
https://reviews.llvm.org/D35933
llvm-svn: 310463
This adds support for the main 128-bit atomic operations,
using the SystemZ instructions LPQ, STPQ, and CDSG.
Generating these instructions is a bit more complex than usual
since the i128 type is not legal for the back-end. Therefore,
we have to hook the LowerOperationWrapper and ReplaceNodeResults
TargetLowering callbacks.
llvm-svn: 310094
We currently emit a serialization operation (bcr 14, 0) before every
atomic load and after every atomic store. This is overly conservative.
The SystemZ architecture actually does not require any serialization
for atomic loads, and a serialization after an atomic store only if
we need to enforce sequential consistency. This is what other compilers
for the platform implement as well.
llvm-svn: 310093
This patch makes LSR generate better code for SystemZ in the cases of memory
intrinsics, Load->Store pairs or comparison of immediate with memory.
In order to achieve this, the following common code changes were made:
* New TTI hook: LSRWithInstrQueries(), which defaults to false. Controls if
LSR should do instruction-based addressing evaluations by calling
isLegalAddressingMode() with the Instruction pointers.
* In LoopStrengthReduce: handle address operands of memset, memmove and memcpy
as address uses, and call isFoldableMemAccessOffset() for any LSRUse::Address,
not just loads or stores.
SystemZ changes:
* isLSRCostLess() implemented with Insns first, and without ImmCost.
* New function supportedAddressingMode() that is a helper for TTI methods
looking at Instructions passed via pointers.
Review: Ulrich Weigand, Quentin Colombet
https://reviews.llvm.org/D35262https://reviews.llvm.org/D35049
llvm-svn: 308729
This adds support for the new 128-bit vector float instructions of z14.
Note that these instructions actually only operate on the f128 type,
since only each 128-bit vector register can hold only one 128-bit
float value. However, this is still preferable to the legacy 128-bit
float instructions, since those operate on pairs of floating-point
registers (so we can hold at most 8 values in registers), while the
new instructions use single vector registers (so we hold up to 32
value in registers).
Adding support includes:
- Enabling the instructions for the assembler/disassembler.
- CodeGen for the instructions. This includes allocating the f128
type now to the VR128BitRegClass instead of FP128BitRegClass.
- Scheduler description support for the instructions.
Note that for a small number of operations, we have no new vector
instructions (like integer <-> 128-bit float conversions), and so
we use the legacy instruction and then reformat the operand
(i.e. copy between a pair of floating-point registers and a
vector register).
llvm-svn: 308196
This adds support for the new 32-bit vector float instructions of z14.
This includes:
- Enabling the instructions for the assembler/disassembler.
- CodeGen for the instructions, including new LLVM intrinsics.
- Scheduler description support for the instructions.
- Update to the vector cost function calculations.
In general, CodeGen support for the new v4f32 instructions closely
matches support for the existing v2f64 instructions.
llvm-svn: 308195
This patch series adds support for the IBM z14 processor. This part includes:
- Basic support for the new processor and its features.
- Support for new instructions (except vector 32-bit float and 128-bit float).
- CodeGen for new instructions, including new LLVM intrinsics.
- Scheduler description for the new processor.
- Detection of z14 as host processor.
Support for the new 32-bit vector float and 128-bit vector float
instructions is provided by separate patches.
llvm-svn: 308194
OpenCL 2.0 introduces the notion of memory scopes in atomic operations to
global and local memory. These scopes restrict how synchronization is
achieved, which can result in improved performance.
This change extends existing notion of synchronization scopes in LLVM to
support arbitrary scopes expressed as target-specific strings, in addition to
the already defined scopes (single thread, system).
The LLVM IR and MIR syntax for expressing synchronization scopes has changed
to use *syncscope("<scope>")*, where <scope> can be "singlethread" (this
replaces *singlethread* keyword), or a target-specific name. As before, if
the scope is not specified, it defaults to CrossThread/System scope.
Implementation details:
- Mapping from synchronization scope name/string to synchronization scope id
is stored in LLVM context;
- CrossThread/System and SingleThread scopes are pre-defined to efficiently
check for known scopes without comparing strings;
- Synchronization scope names are stored in SYNC_SCOPE_NAMES_BLOCK in
the bitcode.
Differential Revision: https://reviews.llvm.org/D21723
llvm-svn: 307722
Several integer multiply/divide instructions require use of a
register pair as input and output. This patch moves setting
up the input register pair from C++ code to TableGen, simplifying
the whole process and making it more easily extensible.
No functional change.
llvm-svn: 307155
Csmith discovered that this function can be called with a zero argument,
in which case an assert for this triggered.
This patch also adds a guard before the other call to this function since
it was missing, although the test only covers the case where it was
discovered.
Reduced test case attached as CodeGen/SystemZ/int-cmp-54.ll.
Review: Ulrich Weigand
llvm-svn: 306287
This reverts the use of TargetLowering::prepareVolatileOrAtomicLoad
introduced by r196905. Nothing in the semantics of the "volatile"
keyword or the definition of the z/Architecture actually requires
that volatile loads are preceded by a serialization operation, and
no other compiler on the platform actually implements this.
Since we've now seen a use case where this additional serialization
causes noticable performance degradation, this patch removes it.
The patch still leaves in the serialization before atomic loads,
which is now implemented directly in lowerATOMIC_LOAD. (This also
seems overkill, but that can be addressed separately.)
llvm-svn: 306117
Use VLREP when inserting one or more loads into a vector. This is more
efficient than to first load and then use a VLVGP.
Review: Ulrich Weigand
llvm-svn: 304152
This method must return a valid register class, or the list-ilp isel
scheduler will crash. For MVT::Untyped nullptr was previously returned, but
now ADDR128BitRegClass is returned instead. This is needed just as long as
list-ilp (and probably also list-hybrid) is still there.
Review: Ulrich Weigand, A Trick
https://reviews.llvm.org/D32802
llvm-svn: 302649
Using arguments with attribute inalloca creates problems for verification
of machine representation. This attribute instructs the backend that the
argument is prepared in stack prior to CALLSEQ_START..CALLSEQ_END
sequence (see http://llvm.org/docs/InAlloca.htm for details). Frame size
stored in CALLSEQ_START in this case does not count the size of this
argument. However CALLSEQ_END still keeps total frame size, as caller can
be responsible for cleanup of entire frame. So CALLSEQ_START and
CALLSEQ_END keep different frame size and the difference is treated by
MachineVerifier as stack error. Currently there is no way to distinguish
this case from actual errors.
This patch adds additional argument to CALLSEQ_START and its
target-specific counterparts to keep size of stack that is set up prior to
the call frame sequence. This argument allows MachineVerifier to calculate
actual frame size associated with frame setup instruction and correctly
process the case of inalloca arguments.
The changes made by the patch are:
- Frame setup instructions get the second mandatory argument. It
affects all targets that use frame pseudo instructions and touched many
files although the changes are uniform.
- Access to frame properties are implemented using special instructions
rather than calls getOperand(N).getImm(). For X86 and ARM such
replacement was made previously.
- Changes that reflect appearance of additional argument of frame setup
instruction. These involve proper instruction initialization and
methods that access instruction arguments.
- MachineVerifier retrieves frame size using method, which reports sum of
frame parts initialized inside frame instruction pair and outside it.
The patch implements approach proposed by Quentin Colombet in
https://bugs.llvm.org/show_bug.cgi?id=27481#c1.
It fixes 9 tests failed with machine verifier enabled and listed
in PR27481.
Differential Revision: https://reviews.llvm.org/D32394
llvm-svn: 302527
This patch replaces the separate APInts for KnownZero/KnownOne with a single KnownBits struct. This is similar to what was done to ValueTracking's version recently.
This is largely a mechanical transformation from KnownZero to Known.Zero.
Differential Revision: https://reviews.llvm.org/D32569
llvm-svn: 301620
getArithmeticInstrCost(), getShuffleCost(), getCastInstrCost(),
getCmpSelInstrCost(), getVectorInstrCost(), getMemoryOpCost(),
getInterleavedMemoryOpCost() implemented.
Interleaved access vectorization enabled.
BasicTTIImpl::getCastInstrCost() improved to check for legal extending loads,
in which case the cost of the z/sext instruction becomes 0.
Review: Ulrich Weigand, Renato Golin.
https://reviews.llvm.org/D29631
llvm-svn: 300052
A test case was found with llvm-stress that caused DAGCombiner to crash
when compiling for an older subtarget without vector support.
SystemZTargetLowering::combineTruncateExtract() should do nothing for older
subtargets.
This check was placed in canTreatAsByteVector(), which also helps in a few
other places.
Review: Ulrich Weigand
llvm-svn: 299763
Even on older subtargets that lack vector support, there may be vector values
with just one element in the input program. These are converted during DAG
legalization to scalar values.
The pre-legalize SystemZ DAGCombiner methods should in this circumstance not
touch these nodes. This patch adds a check for this in
SystemZTargetLowering::combineEXTRACT_VECTOR_ELT().
Review: Ulrich Weigand
llvm-svn: 299213
The GeneralShuffle::add() method used to have an assert that made sure that
source elements were at least as big as the destination elements. This was
wrong, since it is actually expected that an EXTRACT_VECTOR_ELT node with a
smaller source element type than the return type gets extended.
Therefore, instead of asserting this, it is just checked and if this is the
case 'false' is returned from the GeneralShuffle::add() method. This case
should be very rare and is not handled further by the backend.
Review: Ulrich Weigand.
llvm-svn: 292888
Rename from addOperand to just add, to match the other method that has been
added to MachineInstrBuilder for adding more than just 1 operand.
See https://reviews.llvm.org/D28057 for the whole discussion.
Differential Revision: https://reviews.llvm.org/D28556
llvm-svn: 291891
A store of an extracted element or a load which gets inserted into a vector,
will be combined into a vector load/store element instruction.
Therefore, isFoldableMemAccessOffset(), which is called by LSR, should
return false in these cases.
Reviewer: Ulrich Weigand
llvm-svn: 291673
This patch moves formation of LOC-type instructions from (late)
IfConversion to the early if-conversion pass, and in some cases
additionally creates them directly from select instructions
during DAG instruction selection.
To make early if-conversion work, the patch implements the
canInsertSelect / insertSelect callbacks. It also implements
the commuteInstructionImpl and FoldImmediate callbacks to
enable generation of the full range of LOC instructions.
Finally, the patch adds support for all instructions of the
load-store-on-condition-2 facility, which allows using LOC
instructions also for high registers.
Due to the use of the GRX32 register class to enable high registers,
we now also have to handle the cases where there are still no single
hardware instructions (conditional move from a low register to a high
register or vice versa). These are converted back to a branch sequence
after register allocation. Since the expandRAPseudos callback is not
allowed to create new basic blocks, this requires a simple new pass,
modelled after the ARM/AArch64 ExpandPseudos pass.
Overall, this patch causes significantly more LOC-type instructions
to be used, and results in a measurable performance improvement.
llvm-svn: 288028
Add the 16 access registers as LLVM registers. This allows removing
a lot of special cases in the assembler and disassembler where we
were handling access registers; this can all just use the generic
register code now.
Also add a bunch of instructions to operate on access registers,
for assembler/disassembler use only. No change in code generation
intended.
llvm-svn: 286283
The change in r279105 causes an infinite loop in some cases, as it sets the upper bits of an AND mask constant, which DAGCombiner::SimplifyDemandedBits then unsets.
This patch reverts that part of the behaviour, instead relying on .td peepholes to perform the transformation to NILL. I reapplied my original fix for the problem addressed by r279105 (unsetting the upper bits, which prevents a compiler abort for a different reason).
Differential Revision: https://reviews.llvm.org/D23781
llvm-svn: 279515
The names of the tablegen defs now match the names of the ISD nodes.
This makes the world a slightly saner place, as previously "fround" matched
ISD::FP_ROUND and not ISD::FROUND.
Differential Revision: https://reviews.llvm.org/D23597
llvm-svn: 279129
Normally, when an AND with a constant is lowered to NILL, the constant value is truncated to 16 bits. However, since r274066, ANDs whose results are used in a shift are caught by a different pattern that does not truncate. The instruction printer expects a 16-bit unsigned immediate operand for NILL, so this results in an abort.
This patch adds code to manually truncate the constant in this situation. The rest of the bits are then set, so we will detect a case for NILL "naturally" rather than using peephole optimizations.
Differential Revision: http://reviews.llvm.org/D21854
llvm-svn: 279105
Refactored so that a LSRUse owns its fixups, as oppsed to letting the
LSRInstance own them. This makes it easier to rate formulas for
LSRUses, since the fixups are available directly. The Offsets vector
has been removed since it was no longer necessary.
New target hook isFoldableMemAccessOffset(), which is used during formula
rating.
For SystemZ, this is useful to express that loads and stores with
float or vector types with a big/negative offset should be avoided in
loops. Without this, LSR will generate a lot of negative offsets that
would require extra instructions for loading the address.
Updated tests:
test/CodeGen/SystemZ/loop-01.ll
Reviewed by: Quentin Colombet and Ulrich Weigand.
https://reviews.llvm.org/D19152
llvm-svn: 278927
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
This adds a new SystemZ-specific intrinsic, llvm.s390.tdc.f(32|64|128),
which maps straight to the test data class instructions. A new IR pass
is added to recognize instructions that can be converted to TDC and
perform the necessary replacements.
Differential Revision: http://reviews.llvm.org/D21949
llvm-svn: 275016
On SystemZ, shift and rotate instructions only use the bottom 6 bits of the shift/rotate amount.
Therefore, if the amount is ANDed with an immediate mask that has all of the bottom 6 bits set, we
can remove the AND operation entirely.
Differential Revision: http://reviews.llvm.org/D21854
llvm-svn: 274650
This is a mechanical change to make TargetLowering API take MachineInstr&
(instead of MachineInstr*), since the argument is expected to be a valid
MachineInstr. In one case, changed a parameter from MachineInstr* to
MachineBasicBlock::iterator, since it was used as an insertion point.
As a side effect, this removes a bunch of MachineInstr* to
MachineBasicBlock::iterator implicit conversions, a necessary step
toward fixing PR26753.
llvm-svn: 274287
Matt Arsenault