Commit Graph

80 Commits

Author SHA1 Message Date
Daniel Sanders 8ead1290e6 [globalisel][tablegen] Add support for C++ predicates on PatFrags and use it to support BFC on ARM.
So far, we've only handled special cases of PatFrag like ImmLeaf. This patch
adds support for the remaining cases using similar mechanisms.

Like most C++ code from SelectionDAG, GISel and DAGISel expect to operate on
different types and representations and as such the code is not compatible
between the two. It's therefore necessary to add an alternative implementation
in the GISelPredicateCode field.

The target test for this feature could easily be done with IntImmLeaf and this
would save on a little boilerplate. The reason I've chosen to implement this
using PatFrag.GISelPredicateCode and not IntImmLeaf is because I was unable to
find a rule that was blocked solely by lack of support for PatFrag predicates. I
found that the ones I investigated as being likely candidates for the test
were further blocked by other things.

llvm-svn: 334871
2018-06-15 23:13:43 +00:00
Roman Tereshin 5f5e55008f [GlobalISel][InstructionSelect] Moving Reg Bank Checks forward, perf patch 9
This patch continues a series of patches started by r332907 (reapplied
as r332917).

In this commit we move register bank checks back from epilogue of
every rule matcher to a position locally close to the rest of the
checks for a particular (nested) instruction.

This increases the number of common conditions within 2nd level
groups.

This is expected to decrease time GlobalISel spends in its
InstructionSelect pass by about 2% for an -O0 build as measured on
sqlite3-amalgamation (http://sqlite.org/download.html) targeting
AArch64 (cross-compile on x86).

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 333144
2018-05-23 23:58:10 +00:00
Roman Tereshin 152fc1605e [GlobalISel][InstructionSelect] Maximizing # of Group's common conditions, perf patch 8
This patch continues a series of patches started by r332907 (reapplied
as r332917).

In this commit we greedily stuff 2nd level GroupMatcher's common
conditions with as many predicates as possible. This is purely
post-processing and it doesn't change which rules are put into the
groups in the first place: that decision is made by looking at the
first common predicate only.

The compile time improvements are minor and well within error margin,
however, it's highly improbable that this transformation could
pessimize performance, thus I'm still committing it for potential
gains for targets not implementing GlobalISel yet and out of tree
targets.

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 333139
2018-05-23 22:50:53 +00:00
Roman Tereshin b1ba127aa8 [GlobalISel][InstructionSelect] Moving type checks forward, perf patch 6
This patch continues a series of patches started by r332907 (reapplied
as r332917)

In this commit we sort type checks towards the beginning of every rule
within the MatchTable as they fail often and it's best to fail early.

This is expected to decrease time GlobalISel spends in its
InstructionSelect pass by roughly 7% for an -O0 build as measured on
sqlite3-amalgamation (http://sqlite.org/download.html) targeting
AArch64. The amalgamation is a large single-file C-source that makes
compiler backend performance improvements to stand out from frontend.
It's also a part of CTMark.

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 333114
2018-05-23 19:16:59 +00:00
Roman Tereshin fedae33efa [GlobalISel][InstructionSelect] MatchTable second level grouping, perf patch 5
This patch continues a series of patches started by r332907 (reapplied
as r332917)

In this commit we start grouping rules with common first condition on
the second level of the table.

This is expected to decrease time GlobalISel spends in its
InstructionSelect pass by roughly 13% for an -O0 build as measured on
sqlite3-amalgamation (http://sqlite.org/download.html) targeting
AArch64.

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 333053
2018-05-23 02:04:19 +00:00
Roman Tereshin 0ee082f3b9 [GlobalISel][InstructionSelect] Switching MatchTable over opcodes, perf patch 4
This patch continues a series of patches started by r332907 (reapplied
as r332917)

In this commit we introduce a new matching opcode GIM_SwitchOpcode
that implements a jump table over opcodes and start emitting them for
root instructions.

This is expected to decrease time GlobalISel spends in its
InstructionSelect pass by roughly 20% for an -O0 build as measured on
sqlite3-amalgamation (http://sqlite.org/download.html) targeting
AArch64.

To some degree, we assume here that the opcodes form a dense set,
which is true at the moment for all upstream targets given the
limitations of our rule importing mechanism.

It might not be true for out of tree targets, specifically due to
pseudo's. If so, we might noticeably increase the size of the
MatchTable with this patch due to padding zeros. This will be
addressed later.

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 333017
2018-05-22 19:37:59 +00:00
Roman Tereshin 19da667599 [GlobalISel][InstructionSelect] Removing redundant num operands and nested def operands checks, perf patch 2
This patch continues a series of patches that decrease time spent by
GlobalISel in its InstructionSelect pass by roughly 60% for -O0 builds
for large inputs as measured on sqlite3-amalgamation
(http://sqlite.org/download.html) targeting AArch64.

This commit specifically removes number of operands checks that are
redundant if the instruction's opcode already guarantees that number
of operands (or more), and also avoids any kind of checks on a def
operand of a nested instruction as everything about it was already
checked at its use.

The expected performance implication is about 3% off InstructionSelect
comparing to the baseline (before the series of patches)

This patch also contains a bit of NFC changes required for further
patches in the series.

Every commit planned shares the same Phabricator Review.

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 332945
2018-05-22 04:31:50 +00:00
Roman Tereshin f1aa348b31 Reapply r332907 "[GlobalISel] Improving InstructionSelect's performance by reducing MatchTable..."
Apparently the compile time problem was caused by the fact that not
all compilers / STL implementations can automatically convert
std::unique_ptr<Derived> to std::unique_ptr<Base>. Fixed (hopefully)
by making sure it's std::unique_ptr<Derived>&& (rvalue ref) to
std::unique_ptr<Base> conversion instead.

llvm-svn: 332917
2018-05-21 23:28:51 +00:00
Roman Tereshin 8bdf7be5bb Revert r332907 "[GlobalISel] Improving InstructionSelect's performance by reducing MatchTable..."
There is a compile time error I didn't see locally, investigating now.

llvm-svn: 332912
2018-05-21 22:21:24 +00:00
Roman Tereshin f0dc9fa934 [GlobalISel] Improving InstructionSelect's performance by reducing MatchTable, mostly NFC, perf patch 1
This patch starts a series of patches that decrease time spent by
GlobalISel in its InstructionSelect pass by roughly 60% for -O0 builds
for large inputs as measured on sqlite3-amalgamation
(http://sqlite.org/download.html) targeting AArch64.

The performance improvements are achieved solely by reducing the
number of matching GIM_* opcodes executed by the MatchTable's
interpreter during the selection by approx. a factor of 30, which also
brings contribution of this particular part of the selection process
to the overall runtime of InstructionSelect pass down from approx.
60-70% to 5-7%, thus making further improvements in this particular
direction not very profitable.

The improvements described above are expected for any target that
doesn't have many complex patterns. The targets that do should
strictly benefit from the changes, but by how much exactly is hard to
estimate beforehand. It's also likely that such target WILL benefit
from further improvements to MatchTable, most likely the ones that
bring it closer to a perfect decision tree.

This commit specifically is rather large mostly NFC commit that does
necessary preparation work and refactoring, there will be a following
series of small patches introducing a specific optimization each
shortly after.

This commit specifically is expected to cause a small compile time
regression (around 2.5% of InstructionSelect pass time), which should
be fixed by the next commit of the series.

Every commit planned shares the same Phabricator Review.

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 332907
2018-05-21 22:04:39 +00:00
Daniel Sanders f84bc3793e [globalisel] Update GlobalISel emitter to match new representation of extending loads
Summary:
Previously, a extending load was represented at (G_*EXT (G_LOAD x)).
This had a few drawbacks:
* G_LOAD had to be legal for all sizes you could extend from, even if
  registers didn't naturally hold those sizes.
* All sizes you could extend from had to be allocatable just in case the
  extend went missing (e.g. by optimization).
* At minimum, G_*EXT and G_TRUNC had to be legal for these sizes. As we
  improve optimization of extends and truncates, this legality requirement
  would spread without considerable care w.r.t when certain combines were
  permitted.
* The SelectionDAG importer required some ugly and fragile pattern
  rewriting to translate patterns into this style.

This patch changes the representation to:
* (G_[SZ]EXTLOAD x)
* (G_LOAD x) any-extends when MMO.getSize() * 8 < ResultTy.getSizeInBits()
which resolves these issues by allowing targets to work entirely in their
native register sizes, and by having a more direct translation from
SelectionDAG patterns.

Each extending load can be lowered by the legalizer into separate extends
and loads, however a target that supports s1 will need the any-extending
load to extend to at least s8 since LLVM does not represent memory accesses
smaller than 8 bit. The legalizer can widenScalar G_LOAD into an
any-extending load but sign/zero-extending loads need help from something
else like a combiner pass. A follow-up patch that adds combiner helpers for
for this will follow.

The new representation requires that the MMO correctly reflect the memory
access so this has been corrected in a couple tests. I've also moved the
extending loads to their own tests since they are (mostly) separate opcodes
now. Additionally, the re-write appears to have invalidated two tests from
select-with-no-legality-check.mir since the matcher table no longer contains
loads that result in s1's and they aren't legal in AArch64 anymore.

Depends on D45540

Reviewers: ab, aditya_nandakumar, bogner, rtereshin, volkan, rovka, javed.absar

Reviewed By: rtereshin

Subscribers: javed.absar, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D45541

llvm-svn: 331601
2018-05-05 20:53:24 +00:00
Roman Tereshin 2df4c22915 [GlobalISel][InstructionSelect] Refactoring out a getMatchTable virtual method + other small NFC's
The main goal is to share getMatchTable between the Instruction
Selector and the Testgen.

The commit also contains some NFC only loosely related to refactoring
out the getMatchTable, but strongly related to the initial Testgen
patch (see https://reviews.llvm.org/D43962)

Reviewers: dsanders, aemerson

Reviewed By: dsanders

Subscribers: rovka, kristof.beyls, llvm-commits, dsanders

Differential Revision: https://reviews.llvm.org/D46096

llvm-svn: 331395
2018-05-02 20:07:15 +00:00
Aditya Nandakumar b63e763847 [GISel]: Make GlobalISelEmitter rule prioritization compatible with selectionDAG
This patch changes GlobalISelEmitter to rank patterns similar to how the
DAG does it (ie it computes a score for a pattern and adds the added
complexity to it).
This is so that the decision tree for GISelSelector remains compatible
with that of SelectionDAG.

https://reviews.llvm.org/D43270

llvm-svn: 325401
2018-02-16 22:37:15 +00:00
Daniel Sanders 08464524c3 [ARM][GISel] PR35965 Constrain RegClasses of nested instructions built from Dst Pattern
Summary:
Apparently, we missed on constraining register classes of VReg-operands of all the instructions
built from a destination pattern but the root (top-level) one. The issue exposed itself
while selecting G_FPTOSI for armv7: the corresponding pattern generates VTOSIZS wrapped
into COPY_TO_REGCLASS, so top-level COPY_TO_REGCLASS gets properly constrained,
while nested VTOSIZS (or rather its destination virtual register to be exact) does not.

Fixing this by issuing GIR_ConstrainSelectedInstOperands for every nested GIR_BuildMI.

https://bugs.llvm.org/show_bug.cgi?id=35965
rdar://problem/36886530

Patch by Roman Tereshin

Reviewers: dsanders, qcolombet, rovka, bogner, aditya_nandakumar, volkan

Reviewed By: dsanders, qcolombet, rovka

Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D42565

llvm-svn: 323692
2018-01-29 21:09:12 +00:00
Volkan Keles f7f2568613 [GlobalISel][TableGen] Add support for SDNodeXForm
Summary:
This patch adds CustomRenderer which renders the matched
operands to the specified instruction.

Targets can enable the matching of SDNodeXForm by adding
a definition that inherits from GICustomOperandRenderer and
GISDNodeXFormEquiv as follows.

def gi_imm8 : GICustomOperandRenderer<"renderImm8”>,
                       GISDNodeXFormEquiv<imm8_xform>;

Custom renderer functions should be of the form:
void render(MachineInstrBuilder &MIB, const MachineInstr &I);

Reviewers: dsanders, ab, rovka

Reviewed By: dsanders

Subscribers: kristof.beyls, javed.absar, llvm-commits, mgrang, qcolombet

Differential Revision: https://reviews.llvm.org/D42012

llvm-svn: 322582
2018-01-16 18:44:05 +00:00
Daniel Sanders 32de8bbd30 [globalisel][tablegen] Allow ImmLeaf predicates to use InstructionSelector members
NFC for currently supported targets. This resolves a problem encountered by
targets such as RISCV that reference `Subtarget` in ImmLeaf predicates.

llvm-svn: 321176
2017-12-20 14:41:51 +00:00
Quentin Colombet ec76d9c47f [TableGen][GlobalISel] Optimize MatchTable for faster instruction selection
*** Context ***

Prior to this patchw, the table generated for matching instruction was
straight forward but highly inefficient.

Basically, each pattern generates its own set of self contained checks
and actions.
E.g., TableGen generated:
// First pattern
CheckNumOperand 3
CheckOpcode G_ADD
...
Build ADDrr
// Second pattern
CheckNumOperand 3
CheckOpcode G_ADD
...
Build ADDri
// Third pattern
CheckNumOperand 3
CheckOpcode G_SUB
...
Build SUBrr

*** Problem ***

Because of that generation, a *lot* of check were redundant between each
pattern and were checked every single time until we reach the pattern
that matches.
E.g., Taking the previous table, let say we are matching a G_SUB, that
means we were going to check all the rules for G_ADD before looking at
the G_SUB rule. In particular we are going to do:
check 3 operands; PASS
check G_ADD; FAIL
; Next rule
check 3 operands; PASS (but we already knew that!)
check G_ADD; FAIL (well it is still not true)
; Next rule
check 3 operands; PASS (really!!)
check G_SUB; PASS (at last :P)

*** Proposed Solution ***

This patch introduces a concept of group of rules (GroupMatcher) that
share some predicates and only get checked once for the whole group.

This patch only creates groups with one nesting level. Conceptually
there is nothing preventing us for having deeper nest level. However,
the current implementation is not smart enough to share the recording
(aka capturing) of values. That limits its ability to do more sharing.

For the given example the current patch will generate:
// First group
CheckOpcode G_ADD

 // First pattern
 CheckNumOperand 3
 ...
 Build ADDrr
 // Second pattern
 CheckNumOperand 3
 ...
 Build ADDri

// Second group
CheckOpcode G_SUB

 // Third pattern
 CheckNumOperand 3
 ...
 Build SUBrr

But if we allowed several nesting level, it could create a sub group
for the checknumoperand 3.
(We would need to call optimizeRules on the rules within a group.)

*** Result ***

With only one level of nesting, the instruction selection pass is up
to 4x faster. For instance, one instruction now takes 500 checks,
instead of 24k! With more nesting we could get in the tens I believe.

Differential Revision: https://reviews.llvm.org/D39034

rdar://problem/34670699

llvm-svn: 321017
2017-12-18 19:47:41 +00:00
Daniel Sanders 3c1c4c0ee0 Revert r319691: [globalisel][tablegen] Split atomic load/store into separate opcode and enable for AArch64.
Some concerns were raised with the direction. Revert while we discuss it and look into an alternative

llvm-svn: 319739
2017-12-05 05:52:07 +00:00
Daniel Sanders 04e4f47e93 [globalisel][tablegen] Split atomic load/store into separate opcode and enable for AArch64.
This patch splits atomics out of the generic G_LOAD/G_STORE and into their own
G_ATOMIC_LOAD/G_ATOMIC_STORE. This is a pragmatic decision rather than a
necessary one. Atomic load/store has little in implementation in common with
non-atomic load/store. They tend to be handled very differently throughout the
backend. It also has the nice side-effect of slightly improving the common-case
performance at ISel since there's no longer a need for an atomicity check in the
matcher table.

All targets have been updated to remove the atomic load/store check from the
G_LOAD/G_STORE path. AArch64 has also been updated to mark
G_ATOMIC_LOAD/G_ATOMIC_STORE legal.

There is one issue with this patch though which also affects the extending loads
and truncating stores. The rules only match when an appropriate G_ANYEXT is
present in the MIR. For example,
  (G_ATOMIC_STORE (G_TRUNC:s16 (G_ANYEXT:s32 (G_ATOMIC_LOAD:s16 X))))
will match but:
  (G_ATOMIC_STORE (G_ATOMIC_LOAD:s16 X))
will not. This shouldn't be a problem at the moment, but as we get better at
eliminating extends/truncates we'll likely start failing to match in some
cases. The current plan is to fix this in a patch that changes the
representation of extending-load/truncating-store to allow the MMO to describe
a different type to the operation.

llvm-svn: 319691
2017-12-04 20:39:32 +00:00
Daniel Sanders 766646517f [globalisel][tablegen] Add support for importing G_ATOMIC_CMPXCHG, G_ATOMICRMW_* rules from SelectionDAG.
GIM_CheckNonAtomic has been replaced by GIM_CheckAtomicOrdering to allow it to support a wider
range of orderings. This has then been used to import patterns using nodes such
as atomic_cmp_swap, atomic_swap, and atomic_load_*.

llvm-svn: 319232
2017-11-28 22:07:05 +00:00
Daniel Sanders f76f315436 [globalisel][tablegen] Generate rule coverage and use it to identify untested rules
Summary:
This patch adds a LLVM_ENABLE_GISEL_COV which, like LLVM_ENABLE_DAGISEL_COV,
causes TableGen to instrument the generated table to collect rule coverage
information. However, LLVM_ENABLE_GISEL_COV goes a bit further than
LLVM_ENABLE_DAGISEL_COV. The information is written to files
(${CMAKE_BINARY_DIR}/gisel-coverage-* by default). These files can then be
concatenated into ${LLVM_GISEL_COV_PREFIX}-all after which TableGen will
read this information and use it to emit warnings about untested rules.

This technique could also be used by SelectionDAG and can be further
extended to detect hot rules and give them priority over colder rules.

Usage:
* Enable LLVM_ENABLE_GISEL_COV in CMake
* Build the compiler and run some tests
* cat gisel-coverage-[0-9]* > gisel-coverage-all
* Delete lib/Target/*/*GenGlobalISel.inc*
* Build the compiler

Known issues:
* ${LLVM_GISEL_COV_PREFIX}-all must be generated as a manual
  step due to a lack of a portable 'cat' command. It should be the
  concatenation of all ${LLVM_GISEL_COV_PREFIX}-[0-9]* files.
* There's no mechanism to discard coverage information when the ruleset
  changes

Depends on D39742

Reviewers: ab, qcolombet, t.p.northover, aditya_nandakumar, rovka

Reviewed By: rovka

Subscribers: vsk, arsenm, nhaehnle, mgorny, kristof.beyls, javed.absar, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D39747

llvm-svn: 318356
2017-11-16 00:46:35 +00:00
Daniel Sanders 7e52367398 [globalisel][tablegen] Import signextload and zeroextload.
Allow a pattern rewriter to be installed in CodeGenDAGPatterns and use it to
correct situations where SelectionDAG and GlobalISel disagree on
representation. For example, it would rewrite:
  (sextload:i32 $ptr)<<unindexedload>><<sextload>><<sextloadi16>
to:
  (sext:i32 (load:i16 $ptr)<<unindexedload>>)

I'd have preferred to replace the fragments and have the expansion happen
naturally as part of PatFrag expansion but the type inferencing system can't
cope with loads of types narrower than those mentioned in register classes.
This is because the SDTCisInt's on the sext constrain both the result and
operand to the 'legal' integer types (where legal is defined as 'a register
class can contain the type') which immediately rules the narrower types out.
Several targets (those with only one legal integer type) would then go on to
crash on the SDTCisOpSmallerThanOp<> when it removes all the possible types
for the result of the extend.

Also, improve isObviouslySafeToFold() slightly to automatically return true for
neighbouring instructions. There can't be any re-ordering problems if
re-ordering isn't happenning. We'll need to improve it further to handle
sign/zero-extending loads when the extend and load aren't immediate neighbours
though.

llvm-svn: 317971
2017-11-11 03:23:44 +00:00
Daniel Sanders 9cbe7c7f93 [globalisel][tablegen] Add support for multi-insn emission
The importer will now accept nested instructions in the result pattern such as
(ADDWrr $a, (SUBWrr $b, $c)). This is only valid when the nested instruction
def's a single vreg and the parent instruction consumes a single vreg where a
nested instruction is specified. The importer will automatically create a vreg
to connect the two using the type information from the pattern. This vreg will
be constrained to the register classes given in the instruction definitions*.

* REG_SEQUENCE is explicitly rejected because of this. The definition doesn't
  constrain to a register class and it therefore needs special handling.

llvm-svn: 317117
2017-11-01 19:57:57 +00:00
Daniel Sanders 1e4569fdc1 [globalisel][tablegen] Fix small spelling nits. NFC
ComplexRendererFn -> ComplexRendererFns
Corrected a couple lingering references to tied operands that were missed.

llvm-svn: 316237
2017-10-20 20:55:29 +00:00
Daniel Sanders ea8711b88e Re-commit r315885: [globalisel][tblgen] Add support for iPTR and implement am_unscaled* and am_indexed*
Summary:
iPTR is a pointer of subtarget-specific size to any address space. Therefore
type checks on this size derive the SizeInBits from a subtarget hook.

At this point, we can import the simplests G_LOAD rules and select load
instructions using them. Further patches will support for the predicates to
enable additional loads as well as the stores.

The previous commit failed on MSVC due to a failure to convert an
initializer_list to a std::vector. Hopefully, MSVC will accept this version.

Depends on D37457

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: kristof.beyls, javed.absar, llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D37458

llvm-svn: 315887
2017-10-16 03:36:29 +00:00
Daniel Sanders a71f454765 [globalisel][tablegen] Implement unindexed load, non-extending load, and MemVT checks
Summary:
This includes some context-sensitivity in the MVT to LLT conversion so that
pointer types are tested correctly.
FIXME: I'm not happy with the way this is done since everything is a
       special-case. I've yet to find a reasonable way to implement it.

select-load.mir fails because <1 x s64> loads in tablegen get priority over s64
loads. This is fixed in the next patch and as such they should be committed
together, I've posted them separately to help with the review.

Depends on D37456

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Subscribers: kristof.beyls, javed.absar, llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D37457

llvm-svn: 315884
2017-10-16 00:56:30 +00:00
Daniel Sanders df39cbae2f Re-commit r315863: [globalisel][tablegen] Import ComplexPattern when used as an operator
Summary:
It's possible for a ComplexPattern to be used as an operator in a match
pattern. This is used by the load/store patterns in AArch64 to name the
suboperands returned by ComplexPattern predicate so that they can be broken
apart and referenced independently in the result pattern.

This patch adds support for this in order to enable the import of load/store
patterns.

Depends on D37445

Hopefully fixed the ambiguous constructor that a large number of bots reported.

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: aemerson, javed.absar, igorb, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D37456

llvm-svn: 315869
2017-10-15 18:22:54 +00:00
Daniel Sanders bb082a36d3 Revert r315863: [globalisel][tablegen] Import ComplexPattern when used as an operator
A large number of bots are failing on an ambiguous constructor call.

llvm-svn: 315866
2017-10-15 17:51:07 +00:00
Daniel Sanders b95b867dd8 [globalisel][tablegen] Import ComplexPattern when used as an operator
Summary:
It's possible for a ComplexPattern to be used as an operator in a match
pattern. This is used by the load/store patterns in AArch64 to name the
suboperands returned by ComplexPattern predicate so that they can be broken
apart and referenced independently in the result pattern.

This patch adds support for this in order to enable the import of load/store
patterns.

Depends on D37445

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: aemerson, javed.absar, igorb, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D37456

llvm-svn: 315863
2017-10-15 17:03:36 +00:00
Daniel Sanders bfa9e2cae7 [globalisel][tablegen] Simplify named operand/operator lookups and fix a wrong-code bug this revealed.
Summary:
Operand variable lookups are now performed by the RuleMatcher rather than
searching the whole matcher hierarchy for a match. This revealed a wrong-code
bug that currently affects ARM and X86 where patterns that use a variable more
than once in the match pattern will be imported but won't check that the
operands are identical. This can cause the tablegen-erated matcher to
accept matches that should be rejected.

Depends on D36569

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Subscribers: aemerson, igorb, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D36618

llvm-svn: 315780
2017-10-14 00:31:58 +00:00
Daniel Sanders 11300cead8 [globalisel][tablegen] Add support for fpimm and import of APInt/APFloat based ImmLeaf.
Summary:
There's only a tablegen testcase for IntImmLeaf and not a CodeGen one
because the relevant rules are rejected for other reasons at the moment.
On AArch64, it's because there's an SDNodeXForm attached to the operand.
On X86, it's because the rule either emits multiple instructions or has
another predicate using PatFrag which cannot easily be supported at the
same time.

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: aemerson, javed.absar, igorb, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D36569

llvm-svn: 315761
2017-10-13 21:28:03 +00:00
Daniel Sanders 4d4e7650dc [globalisel] Add support for ValueType operands in patterns.
It's rare but there are a small number of patterns like this:
    (set i64:$dst, (add i64:$src1, i64:$src2))
These should be equivalent to register classes except they shouldn't check for
a specific register bank.

This doesn't occur in AArch64/ARM/X86 but does occasionally come up in other
in-tree targets such as BPF.

llvm-svn: 315226
2017-10-09 18:14:53 +00:00
Krzysztof Parzyszek 779d98e1c0 TableGen support for parameterized register class information
This replaces TableGen's type inference to operate on parameterized
types instead of MVTs, and as a consequence, some interfaces have
changed:
- Uses of MVTs are replaced by ValueTypeByHwMode.
- EEVT::TypeSet is replaced by TypeSetByHwMode.

This affects the way that types and type sets are printed, and the
tests relying on that have been updated.

There are certain users of the inferred types outside of TableGen
itself, namely FastISel and GlobalISel. For those users, the way
that the types are accessed have changed. For typical scenarios,
these replacements can be used:
- TreePatternNode::getType(ResNo) -> getSimpleType(ResNo)
- TreePatternNode::hasTypeSet(ResNo) -> hasConcreteType(ResNo)
- TypeSet::isConcrete -> TypeSetByHwMode::isValueTypeByHwMode(false)

For more information, please refer to the review page.

Differential Revision: https://reviews.llvm.org/D31951

llvm-svn: 313271
2017-09-14 16:56:21 +00:00
Daniel Sanders 069bb8d45f [globalisel][tablegen] Predicates should start from GIPFP_Invalid+1 not GIPFP_Invalid
This fixes a warning when there are zero defined predicates and also fixes an
unnoticed bug where the first predicate in the table was unusable.

llvm-svn: 311684
2017-08-24 18:54:16 +00:00
Daniel Sanders 2c269f6bf8 Re-commit: [globalisel][tablegen] Add support for ImmLeaf without SDNodeXForm
Summary:
This patch adds support for predicates on imm nodes but only for ImmLeaf and not
for PatLeaf or PatFrag and only where the value does not need to be transformed
before being rendered into the instruction.

The limitation on PatLeaf/PatFrag/SDNodeXForm is due to differences in the
necessary target-supplied C++ for GlobalISel.

Depends on D36085

The previous commit was reverted for breaking the build but this appears to have
been the recurring problem on the Windows bots with tablegen not being re-run
when llvm-tblgen is changed but the .td's aren't. If it re-occurs then forcing a
build with clean=True should fix it but this string should do this in advance:
    Requires a clean build.

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, javed.absar, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D36086

llvm-svn: 311645
2017-08-24 09:11:20 +00:00
Victor Leschuk 3697ebe25f Revert r311546 as it breaks build
http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win/builds/4394

llvm-svn: 311560
2017-08-23 15:21:10 +00:00
Daniel Sanders c3885c4589 [globalisel][tablegen] Add support for ImmLeaf without SDNodeXForm
Summary:
This patch adds support for predicates on imm nodes but only for ImmLeaf and not for PatLeaf or PatFrag and only where the value does not need to be transformed before being rendered into the instruction.

The limitation on PatLeaf/PatFrag/SDNodeXForm is due to differences in the necessary target-supplied C++ for GlobalISel.

Depends on D36085

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, javed.absar, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D36086

llvm-svn: 311546
2017-08-23 12:14:18 +00:00
Daniel Sanders 499807079b [globalisel][tablegen] Add tests for FeatureBitsets and ComplexPattern predicates.
llvm-svn: 311542
2017-08-23 10:09:25 +00:00
Daniel Sanders 032e7f2cad [globalisel][tablegen] Generate TypeObject table. NFC
Summary:
Generate the type table from the types used by a target rather than hard-coding
the union of types used by all targets.

Depends on D36084

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D36085

llvm-svn: 311084
2017-08-17 13:18:35 +00:00
Daniel Sanders eb2f5f3256 Revert r310919 - [globalisel][tablegen] Support zero-instruction emission.
As expected, this failed on the windows bots but the instrumentation showed
something interesting. The ADD8ri and INC8r rules are never directly compared
on the windows machines. That implies that the issue lies in transitivity of
the Compare predicate. I believe I've already verified that but maybe I missed
something.

llvm-svn: 310922
2017-08-15 15:10:31 +00:00
Daniel Sanders 16e6dd3cd6 Re-commit with some instrumentation: [globalisel][tablegen] Support zero-instruction emission.
Summary:
Support the case where an operand of a pattern is also the whole of the
result pattern. In this case the original result and all its uses must be
replaced by the operand. However, register class restrictions can require
a COPY. This patch handles both cases by always emitting the copy and
leaving it for the register allocator to optimize.

The previous commit failed on the windows bots and this one is likely to fail
on those same bots. However, the added instrumentation should reveal a particular
isHigherPriorityThan() evaluation which I'm expecting to expose that
these machines are weighing priority of two rules differently from the
non-windows machines.

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Subscribers: javed.absar, kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D36084

llvm-svn: 310919
2017-08-15 13:50:09 +00:00
Daniel Sanders e6c216ed5b Revert r310716 (and r310735): [globalisel][tablegen] Support zero-instruction emission.
Two of the Windows bots are failing test\CodeGen\X86\GlobalISel\select-inc.mir
which should not have been affected by the change. Reverting while I investigate.

Also reverted r310735 because it builds on r310716.

llvm-svn: 310745
2017-08-11 19:19:21 +00:00
Daniel Sanders 6ac981151e [globalisel][tablegen] Generate TypeObject table. NFC
Summary:
Generate the type table from the types used by a target rather than hard-coding
the union of types used by all targets.

Depends on D36084

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D36085

llvm-svn: 310735
2017-08-11 17:30:37 +00:00
Daniel Sanders 0554004698 [globalisel][tablegen] Add support for importing 'imm' operands.
Summary:
This patch enables the import of rules containing 'imm' operands that do not
constrain the acceptable values using predicates. Support for ImmLeaf will
arrive in a later patch.

Depends on D35681

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, javed.absar, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D35833

llvm-svn: 310343
2017-08-08 10:44:31 +00:00
Florian Hahn 3bc3ec661c [GlobalISel] Only merge memory ops for mayLoad or mayStore instrs.
Summary:
We only need to merge memory operands for instructions that access
 memory. This slightly reduces the number of actions executed. 

Reviewers: MatzeB, rovka, dsanders

Reviewed By: dsanders

Subscribers: aemerson, igorb, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D36151

llvm-svn: 309944
2017-08-03 14:48:22 +00:00
Daniel Sanders 078572b6b1 [globalisel][tablegen] Do not merge memoperands from instructions that weren't in the match.
Summary:
Fix a bug discovered in an out-of-tree target where memoperands from
pseudo-instructions that weren't part of the match were being merged into the
result instructions as part of GIR_MergeMemOperands.

This bug was caused by a change to the handling of State.MIs between rules when
the state machine tables were fused into a single table. Previously, each rule
would reset State.MIs using State.MIs.resize(1) but this is no longer done, as a
result stale data is occasionally left in some elements of State.MIs. Most
opcodes aren't affected by this but GIR_MergeMemOperands merges all memoperands
from the intructions recorded in State.MIs into the result instruction.

Suppose for example, we processed but rejected the following pattern:
  (signextend (load x))
at this point, State.MIs contains the signextend and the load. Now suppose we
process and accept this pattern:
  (add x, y)
at this point, State.MIs contains the add as well as the (now irrelevant) load.
When GIR_MergeMemOperands is processed, the memoperands from that irrelevant
load will be merged into the result instruction even though it was not part of
the match.

Bringing back the State.MIs.resize(1) would fix the problem but it would limit
our ability to optimize the table in the future. Instead, this patch fixes the
problem by explicitly stating which instructions should be merged into the result.

There's no direct test case in this commit because a test case would be very brittle.
However, at the time of writing this should fix the failures in
http://green.lab.llvm.org/green/job/Compiler_Verifiers_GlobalISEL/ as well as a
failure in test/CodeGen/ARM/GlobalISel/arm-isel.ll when expensive checks are enabled.

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Subscribers: fhahn, kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D36094

llvm-svn: 309804
2017-08-02 11:03:36 +00:00
Daniel Sanders 8e82af2be6 Re-commit: r309094 [globalisel][tablegen] Fuse the generated tables together.
Summary:
Now that we have control flow in place, fuse the per-rule tables into a
single table. This is a compile-time saving at this point. However, this will
also enable the optimization of a table so that similar instructions can be
tested together, reducing the time spent on the matching the code.

This is NFC in terms of externally visible behaviour but some internals have
changed slightly. State.MIs is no longer reset between each rule that is
attempted because it's not necessary to do so. As a consequence of this the
restriction on the order that instructions are added to State.MIs has been
relaxed to only affect recorded instructions that require new elements to be
added to the vector. GIM_RecordInsn can now write to any element from 1 to
State.MIs.size() instead of just State.MIs.size().

The compile-time regressions from the last commit were caused by the ARM target
including a non-const variable (zero_reg) in the table and therefore generating
an initializer for it. That variable is now const.

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D35681

llvm-svn: 309264
2017-07-27 11:03:45 +00:00
Daniel Sanders d3077a94a8 Revert r309094: [globalisel][tablegen] Fuse the generated tables together.
The ARM bots have started failing and while this patch should be an improvement
for these bots, it's also the only suspect in the blamelist. Reverting while
Diana and I investigate the problem.

llvm-svn: 309111
2017-07-26 13:28:40 +00:00
Daniel Sanders d83817ad6e [globalisel][tablegen] Fuse the generated tables together.
Summary:
Now that we have control flow in place, fuse the per-rule tables into a
single table. This is a compile-time saving at this point. However, this will
also enable the optimization of a table so that similar instructions can be
tested together, reducing the time spent on the matching the code.

This is NFC in terms of externally visible behaviour but some internals have
changed slightly. State.MIs is no longer reset between each rule that is
attempted because it's not necessary to do so. As a consequence of this the
restriction on the order that instructions are added to State.MIs has been
relaxed to only affect recorded instructions that require new elements to be
added to the vector. GIM_RecordInsn can now write to any element from 1 to
State.MIs.size() instead of just State.MIs.size().

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D35681

llvm-svn: 309094
2017-07-26 10:20:56 +00:00
Daniel Sanders 7aac7cc57f [globalisel][tablegen] Add control-flow to the MatchTable.
Summary:
This will allow us to merge the various sub-tables into a single table. This is a
compile-time saving at this point. However, this will also enable the optimization
of a table so that similar instructions can be tested together, reducing the time
spent on the matching the code.

The bulk of this patch is a mechanical conversion to the new MatchTable object
which is responsible for tracking label definitions and filling in the index of
the jump targets. It is also responsible for nicely formatting the table.

This was necessary to support the new GIM_Try opcode which takes the index to
jump to if the match should fail. This value is unknown during table
construction and is filled in during emission. To support nesting try-blocks
(although we currently don't emit tables with nested try-blocks), GIM_Reject
has been re-introduced to explicitly exit a try-block or fail the overall match
if there are no active try-blocks.

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D35117

llvm-svn: 308596
2017-07-20 09:25:44 +00:00