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
artifacts along with DCE
Legalization Artifacts are all those insts that are there to make the
type system happy. Currently, the target needs to say all combinations
of extends and truncs are legal and there's no way of verifying that
post legalization, we only have *truly* legal instructions. This patch
changes roughly the legalization algorithm to process all illegal insts
at one go, and then process all truncs/extends that were added to
satisfy the type constraints separately trying to combine trivial cases
until they converge. This has the added benefit that, the target
legalizerinfo can only say which truncs and extends are okay and the
artifact combiner would combine away other exts and truncs.
Updated legalization algorithm to roughly the following pseudo code.
WorkList Insts, Artifacts;
collect_all_insts_and_artifacts(Insts, Artifacts);
do {
for (Inst in Insts)
legalizeInstrStep(Inst, Insts, Artifacts);
for (Artifact in Artifacts)
tryCombineArtifact(Artifact, Insts, Artifacts);
} while(!Insts.empty());
Also, wrote a simple wrapper equivalent to SetVector, except for
erasing, it avoids moving all elements over by one and instead just
nulls them out.
llvm-svn: 318210
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
This header includes CodeGen headers, and is not, itself, included by
any Target headers, so move it into CodeGen to match the layering of its
implementation.
llvm-svn: 317647
This changes the interface of how targets describe how to legalize, see
the below description.
1. Interface for targets to describe how to legalize.
In GlobalISel, the API in the LegalizerInfo class is the main interface
for targets to specify which types are legal for which operations, and
what to do to turn illegal type/operation combinations into legal ones.
For each operation the type sizes that can be legalized without having
to change the size of the type are specified with a call to setAction.
This isn't different to how GlobalISel worked before. For example, for a
target that supports 32 and 64 bit adds natively:
for (auto Ty : {s32, s64})
setAction({G_ADD, 0, s32}, Legal);
or for a target that needs a library call for a 32 bit division:
setAction({G_SDIV, s32}, Libcall);
The main conceptual change to the LegalizerInfo API, is in specifying
how to legalize the type sizes for which a change of size is needed. For
example, in the above example, how to specify how all types from i1 to
i8388607 (apart from s32 and s64 which are legal) need to be legalized
and expressed in terms of operations on the available legal sizes
(again, i32 and i64 in this case). Before, the implementation only
allowed specifying power-of-2-sized types (e.g. setAction({G_ADD, 0,
s128}, NarrowScalar). A worse limitation was that if you'd wanted to
specify how to legalize all the sized types as allowed by the LLVM-IR
LangRef, i1 to i8388607, you'd have to call setAction 8388607-3 times
and probably would need a lot of memory to store all of these
specifications.
Instead, the legalization actions that need to change the size of the
type are specified now using a "SizeChangeStrategy". For example:
setLegalizeScalarToDifferentSizeStrategy(
G_ADD, 0, widenToLargerAndNarrowToLargest);
This example indicates that for type sizes for which there is a larger
size that can be legalized towards, do it by Widening the size.
For example, G_ADD on s17 will be legalized by first doing WidenScalar
to make it s32, after which it's legal.
The "NarrowToLargest" indicates what to do if there is no larger size
that can be legalized towards. E.g. G_ADD on s92 will be legalized by
doing NarrowScalar to s64.
Another example, taken from the ARM backend is:
for (unsigned Op : {G_SDIV, G_UDIV}) {
setLegalizeScalarToDifferentSizeStrategy(Op, 0,
widenToLargerTypesUnsupportedOtherwise);
if (ST.hasDivideInARMMode())
setAction({Op, s32}, Legal);
else
setAction({Op, s32}, Libcall);
}
For this example, G_SDIV on s8, on a target without a divide
instruction, would be legalized by first doing action (WidenScalar,
s32), followed by (Libcall, s32).
The same principle is also followed for when the number of vector lanes
on vector data types need to be changed, e.g.:
setAction({G_ADD, LLT::vector(8, 8)}, LegalizerInfo::Legal);
setAction({G_ADD, LLT::vector(16, 8)}, LegalizerInfo::Legal);
setAction({G_ADD, LLT::vector(4, 16)}, LegalizerInfo::Legal);
setAction({G_ADD, LLT::vector(8, 16)}, LegalizerInfo::Legal);
setAction({G_ADD, LLT::vector(2, 32)}, LegalizerInfo::Legal);
setAction({G_ADD, LLT::vector(4, 32)}, LegalizerInfo::Legal);
setLegalizeVectorElementToDifferentSizeStrategy(
G_ADD, 0, widenToLargerTypesUnsupportedOtherwise);
As currently implemented here, vector types are legalized by first
making the vector element size legal, followed by then making the number
of lanes legal. The strategy to follow in the first step is set by a
call to setLegalizeVectorElementToDifferentSizeStrategy, see example
above. The strategy followed in the second step
"moreToWiderTypesAndLessToWidest" (see code for its definition),
indicating that vectors are widened to more elements so they map to
natively supported vector widths, or when there isn't a legal wider
vector, split the vector to map it to the widest vector supported.
Therefore, for the above specification, some example legalizations are:
* getAction({G_ADD, LLT::vector(3, 3)})
returns {WidenScalar, LLT::vector(3, 8)}
* getAction({G_ADD, LLT::vector(3, 8)})
then returns {MoreElements, LLT::vector(8, 8)}
* getAction({G_ADD, LLT::vector(20, 8)})
returns {FewerElements, LLT::vector(16, 8)}
2. Key implementation aspects.
How to legalize a specific (operation, type index, size) tuple is
represented by mapping intervals of integers representing a range of
size types to an action to take, e.g.:
setScalarAction({G_ADD, LLT:scalar(1)},
{{1, WidenScalar}, // bit sizes [ 1, 31[
{32, Legal}, // bit sizes [32, 33[
{33, WidenScalar}, // bit sizes [33, 64[
{64, Legal}, // bit sizes [64, 65[
{65, NarrowScalar} // bit sizes [65, +inf[
});
Please note that most of the code to do the actual lowering of
non-power-of-2 sized types is currently missing, this is just trying to
make it possible for targets to specify what is legal, and how non-legal
types should be legalized. Probably quite a bit of further work is
needed in the actual legalizing and the other passes in GlobalISel to
support non-power-of-2 sized types.
I hope the documentation in LegalizerInfo.h and the examples provided in the
various {Target}LegalizerInfo.cpp and LegalizerInfoTest.cpp explains well
enough how this is meant to be used.
This drops the need for LLT::{half,double}...Size().
Differential Revision: https://reviews.llvm.org/D30529
llvm-svn: 317560
This header already includes a CodeGen header and is implemented in
lib/CodeGen, so move the header there to match.
This fixes a link error with modular codegeneration builds - where a
header and its implementation are circularly dependent and so need to be
in the same library, not split between two like this.
llvm-svn: 317379
Summary: Make sure shifts are legal/specified by the legalizerinfo before creating it
Reviewers: qcolombet, dsanders, rovka, t.p.northover
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39264
llvm-svn: 316602
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
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.
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: 315885
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
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
TargetRegisterInfo::getMinimalPhysRegClass is actually pretty expensive
because it has to iterate over all the register classes.
Cache this information as we need and get it so that we limit its usage.
Right now, we heavily rely on it, because this is how we get the mapping
for vregs defined by copies from physreg (i.e., the one that are ABI
related).
Improve compile time by up to 10% for that pass.
NFC
llvm-svn: 315759
Prior to this patch we used to create SetVectors in temporaries that
were created and destroyed for each instruction. Now, instead we create
and destroyed them only once, but clear the content for each
instruction.
This speeds up the pass by ~25%.
NFC.
llvm-svn: 315756
Summary:
Add LLVM_FORCE_ENABLE_DUMP cmake option, and use it along with
LLVM_ENABLE_ASSERTIONS to set LLVM_ENABLE_DUMP.
Remove NDEBUG and only use LLVM_ENABLE_DUMP to enable dump methods.
Move definition of LLVM_ENABLE_DUMP from config.h to llvm-config.h so
it'll be picked up by public headers.
Differential Revision: https://reviews.llvm.org/D38406
llvm-svn: 315590
We end up creating COPY's that are either truncating/extending and this
should be illegal.
https://reviews.llvm.org/D37640
Patch for X86 and ARM by igorb, rovka
llvm-svn: 315240
r313390 taught 'allowExtraAnalysis' to check whether remarks are
enabled at all. Use that to only do the expensive instruction printing
if they are.
llvm-svn: 313552
Added a combiner which can clean up truncs/extends that are created in
order to make the types work during legalization.
Also moved the combineMerges to the LegalizeCombiner.
https://reviews.llvm.org/D36880
llvm-svn: 312158
Since the lambda isn't escaped (via a std::function or similar) it's
fine/better to use default capture-by-ref to provide semantics similar
to language-level nested scopes (if/for/while/etc).
llvm-svn: 311782
G_PHI has the same semantics as PHI but also has types.
This lets us verify that the types in the G_PHI are consistent.
This also allows specifying legalization actions for G_PHIs.
https://reviews.llvm.org/D36990
llvm-svn: 311596
With this change, the GlobalISel library gets always built. In
particular, this is not possible to opt GlobalISel out of the build
using the LLVM_BUILD_GLOBAL_ISEL variable any more.
llvm-svn: 309990
There is no situation where this rarely-used argument cannot be
substituted with a DIExpression and removing it allows us to simplify
the DWARF backend. Note that this patch does not yet remove any of
the newly dead code.
rdar://problem/33580047
Differential Revision: https://reviews.llvm.org/D35951
llvm-svn: 309426
If the localizer pass puts one of its constants before the label that tells the
unwinder "jump here to handle your exception" then control-flow will skip it,
leaving uninitialized registers at runtime. That's bad.
llvm-svn: 308687
Treat widening G_SREM and G_UREM the same as G_SDIV and G_UDIV. This is
going to be used in the ARM backend (and that's when the test will come
too).
llvm-svn: 308278
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
This covers both hard and soft float.
Hard float is easy, since it's just Legal.
Soft float is more involved, because there are several different ways to
handle it based on the predicate: one and ueq need not only one, but two
libcalls to get a result. Furthermore, we have large differences between
the values returned by the AEABI and GNU functions.
AEABI functions return a nice 1 or 0 representing true and respectively
false. GNU functions generally return a value that needs to be compared
against 0 (e.g. for ogt, the value returned by the libcall is > 0 for
true). We could introduce redundant comparisons for AEABI as well, but
they don't seem easy to remove afterwards, so we do different processing
based on whether or not the result really needs to be compared against
something (and just truncate if it doesn't).
llvm-svn: 307243
Summary:
Also, made a few minor tweaks to shave off a little more cumulative memory consumption:
* All rules share a single NewMIs instead of constructing their own. Only one
will end up using it.
* Use MIs.resize(1) instead of MIs.clear();MIs.push_back(I) and prevent
GIM_RecordInsn from changing MIs[0].
Depends on D33764
Reviewers: rovka, vitalybuka, ab, t.p.northover, qcolombet, aditya_nandakumar
Reviewed By: ab
Subscribers: kristof.beyls, igorb, llvm-commits
Differential Revision: https://reviews.llvm.org/D33766
llvm-svn: 307159
We used to have a helper that replaced an instruction with a libcall.
That turns out to be too aggressive, since sometimes we need to replace
the instruction with at least two libcalls. Therefore, change our
existing helper to only create the libcall and leave the instruction
removal as a separate step. Also rename the helper accordingly.
llvm-svn: 307149
Add a helper for building simple binary ops like add, mul, sub, and.
This can be used in the future for quickly adding support for or, xor.
llvm-svn: 307139
Summary:
This further improves the compile-time regressions that will be caused by a
re-commit of r303259.
Also added included preliminary work in preparation for the multi-insn emitter
since I needed to change the relevant part of the API for this patch anyway.
Depends on D33758
Reviewers: rovka, vitalybuka, ab, t.p.northover, qcolombet, aditya_nandakumar
Reviewed By: ab
Subscribers: kristof.beyls, igorb, llvm-commits
Differential Revision: https://reviews.llvm.org/D33764
llvm-svn: 307133
Summary:
Replace the matcher if-statements for each rule with a state-machine. This
significantly reduces compile time, memory allocations, and cumulative memory
allocation when compiling AArch64InstructionSelector.cpp.o after r303259 is
recommitted.
The following patches will expand on this further to fully fix the regressions.
Reviewers: rovka, ab, t.p.northover, qcolombet, aditya_nandakumar
Reviewed By: ab
Subscribers: vitalybuka, aemerson, javed.absar, igorb, llvm-commits, kristof.beyls
Differential Revision: https://reviews.llvm.org/D33758
llvm-svn: 307079
It looks like there are two target-independent but not GISel instructions that
need legalization, IMPLICIT_DEF and PHI. These are already anomalies since
their operands have important LLTs attached, so to make things more uniform it
seems like a good idea to add generic variants. Starting with G_IMPLICIT_DEF.
llvm-svn: 306875
In r301116, a custom lowering needed to be introduced to be able to
legalize 8 and 16-bit divisions on ARM targets without a division
instruction, since 2-step legalization (WidenScalar from 8 bit to 32
bit, then Libcall the 32-bit division) doesn't work.
This fixes this and makes this kind of multi-step legalization, where
first the size of the type needs to be changed and then some action is
needed that doesn't require changing the size of the type,
straighforward to specify.
Differential Revision: https://reviews.llvm.org/D32529
llvm-svn: 306806
Without this check, COPY instructions can actually be one of the generic casts
in disguise. That's confusing and bad.
At some point during ISel this restriction has to be relaxed since the fully
selected instructions will usually use COPY for those purposes. Right now I
think it's possible that relaxation occurs during RegBankSelect (hence the
change there). I'm not convinced that's where it belongs long-term though.
llvm-svn: 306470
It was trying to do too many things. The basic lumping together of values for
legalization purposes is now handled by G_MERGE_VALUES. More complex things
involving gaps and odd sizes are handled by G_INSERT sequences.
llvm-svn: 306120
G_SEQUENCE is going away soon so as a first step the MachineIRBuilder needs to
be taught how to emulate it with alternatives. We use G_MERGE_VALUES where
possible, and a sequence of G_INSERTs if not.
llvm-svn: 306119
Summary:
As part of this
* Emitted instructions now have named MachineInstr variables associated
with them. This isn't particularly important yet but it's a small step
towards multiple-insn emission.
* constrainSelectedInstRegOperands() is no longer hardcoded. It's now added
as the ConstrainOperandsToDefinitionAction() action. COPY_TO_REGCLASS uses
an alternate constraint mechanism ConstrainOperandToRegClassAction() which
supports arbitrary constraints such as that defined by COPY_TO_REGCLASS.
Reviewers: ab, qcolombet, t.p.northover, rovka, kristof.beyls, aditya_nandakumar
Reviewed By: ab
Subscribers: javed.absar, igorb, llvm-commits
Differential Revision: https://reviews.llvm.org/D33590
llvm-svn: 305791
Summary:
In some cases legalization ends up with not symmetric merge/unmerge nodes.
Transform it to merge/unmerge nodes.
Reviewers: t.p.northover, qcolombet, zvi
Reviewed By: t.p.northover
Subscribers: rovka, kristof.beyls, guyblank, llvm-commits
Differential Revision: https://reviews.llvm.org/D33626
llvm-svn: 305783
Add support for modulo for targets that have hardware division and for
those that don't. When hardware division is not available, we have to
choose the correct libcall to use. This is generally straightforward,
except for AEABI.
The AEABI variant is trickier than the other libcalls because it
returns { quotient, remainder }, instead of just one value like the
other libcalls that we've seen so far. Therefore, we need to use custom
lowering for it. However, we don't want to have too much special code,
so we refactor the target-independent code in the legalizer by adding a
helper for replacing an instruction with a libcall. This helper is used
by the legalizer itself when dealing with simple calls, and also by the
custom ARM legalization for the more complicated AEABI divmod calls.
llvm-svn: 305459
Summary:
When legalizing G_LOAD/G_STORE using NarrowScalar, we should avoid emitting
%0 = G_CONSTANT ty 0
%1 = G_GEP %x, %0
since it's cheaper to not emit the redundant instructions than it is to fold them
away later.
Reviewers: qcolombet, t.p.northover, ab, rovka, aditya_nandakumar, kristof.beyls
Reviewed By: qcolombet
Subscribers: javed.absar, llvm-commits, igorb
Differential Revision: https://reviews.llvm.org/D32746
llvm-svn: 305340
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.
I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.
This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.
Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).
llvm-svn: 304787
There is no guarantee that the first use of a constant that is traversed
is actually the first in the related basic block. Thus, if we use that
as the insertion point we may end up with definitions that don't
dominate there use.
llvm-svn: 304244
This reverts commit r299287 plus clean-ups.
The localizer pass is a helper pass that could be run at O0 in the GISel
pipeline to work around the deficiency of the fast register allocator.
It basically shortens the live-ranges of the constants so that the
allocator does not spill all over the place.
Long term fix would be to make the greedy allocator fast.
llvm-svn: 304051
Summary:
As of this patch, 1018 out of 3938 rules are currently imported.
Depends on D32275
Reviewers: qcolombet, kristof.beyls, rovka, t.p.northover, ab, aditya_nandakumar
Reviewed By: qcolombet
Subscribers: dberris, igorb, llvm-commits
Differential Revision: https://reviews.llvm.org/D32278
The previous commit failed on test-suite/Bitcode/simd_ops/AArch64_halide_runtime.bc
because isImmOperandEqual() assumed MO was a register operand and that's not
always true.
llvm-svn: 303341
Make sure IRTranslator->MachineIRBuilder->DebugLoc doesn't
outlive the DILocation. Clear it at the end of
IRTranslator::runOnMachineFunction
llvm-svn: 303277
Summary:
We were asserting in RegisterBankInfo if RBI.copyCost() returns
UINT_MAX. This is OK for RegBankSelect::Mode::Fast since we only
try one instruction mapping and can't recover from this, but for
RegBankSelect::Mode::Greedy we will be considering multiple
instruction mappings, so we can recover if we see a UNIT_MAX copy
cost.
The copy cost for one pair of register banks in the AMDGPU backend
will be UNIT_MAX, so this patch will prevent AMDGPU tests from
breaking.
Reviewers: ab, qcolombet, t.p.northover, dsanders
Reviewed By: qcolombet
Subscribers: tpr, llvm-commits
Differential Revision: https://reviews.llvm.org/D33144
llvm-svn: 303043
We end up dereferencing the end iterator here when the Aspect doesn't exist in the DefaultAction map.
Change the API to return Optional<LLT> and return None when not found.
Also update the callers to handle the None case
llvm-svn: 302963
This is a step toward having statically allocated instruciton mapping.
We are going to tablegen them eventually, so let us reflect that in
the API.
NFC.
llvm-svn: 302316
This exposes a method in MachineFrameInfo that calculates
MaxCallFrameSize and calls it after instruction selection in the ARM
target.
This avoids
ARMBaseRegisterInfo::canRealignStack()/ARMFrameLowering::hasReservedCallFrame()
giving different answers in early/late phases of codegen.
The testcase shows a particular nasty example result of that where we
would fail to properly align an alloca.
Differential Revision: https://reviews.llvm.org/D32622
llvm-svn: 302303
During legalization, targets can create Pseudo Instructions with
generic types. We shouldn't try to legalize them.
Reviewed by Quentin, dsanders
https://reviews.llvm.org/D32575
llvm-svn: 302199
Summary:
Do three things to help with that:
- Add AttributeList::FirstArgIndex, which is an enumerator currently set
to 1. It allows us to change the indexing scheme with fewer changes.
- Add addParamAttr/removeParamAttr. This just shortens addAttribute call
sites that would otherwise need to spell out FirstArgIndex.
- Remove some attribute-specific getters and setters from Function that
take attribute list indices. Most of these were only used from
BuildLibCalls, and doesNotAlias was only used to test or set if the
return value is malloc-like.
I'm happy to split the patch, but I think they are probably easier to
review when taken together.
This patch should be NFC, but it sets the stage to change the indexing
scheme to this, which is more convenient when indexing into an array:
0: func attrs
1: retattrs
2...: arg attrs
Reviewers: chandlerc, pete, javed.absar
Subscribers: david2050, llvm-commits
Differential Revision: https://reviews.llvm.org/D32811
llvm-svn: 302060
Summary:
Predicate<> now has a field to indicate how often it must be recomputed.
Currently, there are two frequencies, per-module (RecomputePerFunction==0)
and per-function (RecomputePerFunction==1). Per-function predicates are
currently recomputed more frequently than necessary since the only predicate
in this category is cheap to test. Per-module predicates are now computed in
getSubtargetImpl() while per-function predicates are computed in selectImpl().
Tablegen now manages the PredicateBitset internally. It should only be
necessary to add the required includes.
Also fixed a problem revealed by the test case where
constrainSelectedInstRegOperands() would attempt to tie operands that
BuildMI had already tied.
Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar
Reviewed By: rovka
Subscribers: kristof.beyls, igorb, llvm-commits
Differential Revision: https://reviews.llvm.org/D32491
llvm-svn: 301750
This broke the Clang build. (Clang-side patch missing?)
Original commit message:
> [IR] Make add/remove Attributes use AttrBuilder instead of
> AttributeList
>
> This change cleans up call sites and avoids creating temporary
> AttributeList objects.
>
> NFC
llvm-svn: 301712
The method is called "get *Param* Alignment", and is only used for
return values exactly once, so it should take argument indices, not
attribute indices.
Avoids confusing code like:
IsSwiftError = CS->paramHasAttr(ArgIdx, Attribute::SwiftError);
Alignment = CS->getParamAlignment(ArgIdx + 1);
Add getRetAlignment to handle the one case in Value.cpp that wants the
return value alignment.
This is a potentially breaking change for out-of-tree backends that do
their own call lowering.
llvm-svn: 301682
Adds a new method finalizeLowering to TargetLoweringBase. This is in
preparation for an upcoming commit.
This function is meant for target specific adjustments to
MachineFrameInfo or register reservations.
Move the freezeRegisters() and the hasCopyImplyingStackAdjustment()
handling into the new function to prove the concept. As an added bonus
GlobalISel no longer missed the hasCopyImplyingStackAdjustment()
handling with this.
Differential Revision: https://reviews.llvm.org/D32621
llvm-svn: 301679
1. RegisterClass::getSize() is split into two functions:
- TargetRegisterInfo::getRegSizeInBits(const TargetRegisterClass &RC) const;
- TargetRegisterInfo::getSpillSize(const TargetRegisterClass &RC) const;
2. RegisterClass::getAlignment() is replaced by:
- TargetRegisterInfo::getSpillAlignment(const TargetRegisterClass &RC) const;
This will allow making those values depend on subtarget features in the
future.
Differential Revision: https://reviews.llvm.org/D31783
llvm-svn: 301221
Treat them the same as the other binary operations that we have so far,
but on integers rather than floating point types. Extract the common
code into a helper.
This will be used in the ARM backend.
llvm-svn: 301163
This will become asan errors once the patch lands that poisons the
memory after free. The x86 change is a hack, but I don't see how to
solve this properly at the moment.
llvm-svn: 300867
This fixes PR32471.
As comment 10 on that bug report highlights
(https://bugs.llvm.org//show_bug.cgi?id=32471#c10), there are quite a
few different defendable design tradeoffs that could be made, including
not representing pointers at all in LLT.
I decided to go for representing vector-of-pointer as a concept in LLT,
while keeping the size of the LLT type 64 bits (this is an increase from
48 bits before). My rationale for keeping pointers explicit is that on
some targets probably it's very handy to have the distinction between
pointer and non-pointer (e.g. 68K has a different register bank for
pointers IIRC). If we keep a scalar pointer, it probably is easiest to
also have a vector-of-pointers to keep LLT relatively conceptually clean
and orthogonal, while we don't have a very strong reason to break that
orthogonality. Once we gain more experience on the use of LLT, we can
of course reconsider this direction.
Rejecting vector-of-pointer types in the IRTranslator is also an option
to avoid the crash reported in PR32471, but that is only a very
short-term solution; also needs quite a bit of code tweaks in places,
and is probably fragile. Therefore I didn't consider this the best
option.
llvm-svn: 300664
This showed up in r300535/r300537, which were reverted in r300538 due to
some of the introduced tests in there failing on some bots, due to the
non-determinism fixed in this commit.
Re-committing r300535/r300537 will add 2 tests for the change in this
commit.
llvm-svn: 300663
This reverts r300535 and r300537.
The newly added tests in test/CodeGen/AArch64/GlobalISel/arm64-fallback.ll
produces slightly different code between LLVM versions being built with different compilers.
E.g., dependent on the compiler LLVM is built with, either one of the following
can be produced:
remark: <unknown>:0:0: unable to legalize instruction: %vreg0<def>(p0) = G_EXTRACT_VECTOR_ELT %vreg1, %vreg2; (in function: vector_of_pointers_extractelement)
remark: <unknown>:0:0: unable to legalize instruction: %vreg2<def>(p0) = G_EXTRACT_VECTOR_ELT %vreg1, %vreg0; (in function: vector_of_pointers_extractelement)
Non-determinism like this is clearly a bad thing, so reverting this until
I can find and fix the root cause of the non-determinism.
llvm-svn: 300538
This fixes PR32471.
As comment 10 on that bug report highlights
(https://bugs.llvm.org//show_bug.cgi?id=32471#c10), there are quite a
few different defendable design tradeoffs that could be made, including
not representing pointers at all in LLT.
I decided to go for representing vector-of-pointer as a concept in LLT,
while keeping the size of the LLT type 64 bits (this is an increase from
48 bits before). My rationale for keeping pointers explicit is that on
some targets probably it's very handy to have the distinction between
pointer and non-pointer (e.g. 68K has a different register bank for
pointers IIRC). If we keep a scalar pointer, it probably is easiest to
also have a vector-of-pointers to keep LLT relatively conceptually clean
and orthogonal, while we don't have a very strong reason to break that
orthogonality. Once we gain more experience on the use of LLT, we can
of course reconsider this direction.
Rejecting vector-of-pointer types in the IRTranslator is also an option
to avoid the crash reported in PR32471, but that is only a very
short-term solution; also needs quite a bit of code tweaks in places,
and is probably fragile. Therefore I didn't consider this the best
option.
llvm-svn: 300535
Use the same handling in the generic legalizer code as for the other
libcalls (G_FREM, G_FPOW).
Enable it on ARM for float and double so we can test it.
llvm-svn: 299931
Summary: Legalize only if the type is marked as Legal or Custom. If not, return Unsupported as LegalizerHelper is not able to handle non-power-of-2 types right now.
Reviewers: qcolombet, aditya_nandakumar, dsanders, t.p.northover, kristof.beyls, javed.absar, ab
Reviewed By: kristof.beyls, ab
Subscribers: dberris, rovka, igorb, llvm-commits
Differential Revision: https://reviews.llvm.org/D31711
llvm-svn: 299929
The original instruction might get legalized and erased and expanded
into intermediate instructions and the intermediate instructions might
fail legalization. This end up in reporting GISelFailure on the erased
instruction.
Instead report GISelFailure on the intermediate instruction which failed
legalization.
Reviewed by: ab
llvm-svn: 299802
Summary:
Lift the restrictions that prevented the tree walking introduced in the
previous change and add support for patterns like:
(G_ADD (G_MUL (G_SEXT $src1), (G_SEXT $src2)), $src3) -> SMADDWrrr $dst, $src1, $src2, $src3
Also adds support for G_SEXT and G_ZEXT to support these cases.
One particular aspect of this that I should draw attention to is that I've
tried to be overly conservative in determining the safety of matches that
involve non-adjacent instructions and multiple basic blocks. This is intended
to be used as a cheap initial check and we may add a more expensive check in
the future. The current rules are:
* Reject if any instruction may load/store (we'd need to check for intervening
memory operations.
* Reject if any instruction has implicit operands.
* Reject if any instruction has unmodelled side-effects.
See isObviouslySafeToFold().
Reviewers: t.p.northover, javed.absar, qcolombet, aditya_nandakumar, ab, rovka
Reviewed By: ab
Subscribers: igorb, dberris, llvm-commits, kristof.beyls
Differential Revision: https://reviews.llvm.org/D30539
llvm-svn: 299430
REG_SEQUENCE falls into the same category as COPY for operands mapping:
- They don't have MCInstrDesc with register constraints
- The input variable could use whatever register classes
- It is possible to have register class already assigned to the operands
In particular, given REG_SEQUENCE are always target specific because of
the subreg indices. Those indices must apply to the register class of
the definition of the REG_SEQUENCE and therefore, the target must set a
register class to that definition. As a result, the generic code can
always use that register class to derive a valid mapping for a
REG_SEQUENCE.
llvm-svn: 299285
This patch changes the behavior of IRTranslating intrinsics where we
now create VREG + G_CONSTANT for ConstantInt values. We already do this
for FloatingPoint values. This makes it easier for the backends to
select code and it won't have to de-duplicate creation+selection of
constants.
Reviewed by: ab
llvm-svn: 298473
Quentin points out that r298358 would cause us to emit different code
with debug info. That's a big no-no; also erase the instructions that
only live thanks to DBG_VALUE users.
Adrian explained how this is an existing problem and an OK thing to do:
clang has allocas for all variables so shouldn't be affected at -O0, but
swift uses a bit of inlineasm to explicitly keep values live for the
purpose of debug info quality. I'm not sure there is a better scheme.
llvm-svn: 298460
MI can represent fallthrough to layout successor blocks, and our
post-isel representation uses that extensively.
We might as well use it too, to avoid translating and carrying along
unnecessary branches.
llvm-svn: 298459
A bool is represented by a single byte, which the ARM ABI requires to be either
0 or 1. So we cannot use G_ANYEXT when legalizing the type.
llvm-svn: 298439
Summary:
This class is a list of AttributeSetNodes corresponding the function
prototype of a call or function declaration. This class used to be
called ParamAttrListPtr, then AttrListPtr, then AttributeSet. It is
typically accessed by parameter and return value index, so
"AttributeList" seems like a more intuitive name.
Rename AttributeSetImpl to AttributeListImpl to follow suit.
It's useful to rename this class so that we can rename AttributeSetNode
to AttributeSet later. AttributeSet is the set of attributes that apply
to a single function, argument, or return value.
Reviewers: sanjoy, javed.absar, chandlerc, pete
Reviewed By: pete
Subscribers: pete, jholewinski, arsenm, dschuff, mehdi_amini, jfb, nhaehnle, sbc100, void, llvm-commits
Differential Revision: https://reviews.llvm.org/D31102
llvm-svn: 298393
This commit adds a parameter that lets us pass in the calling convention
of the call to CallLowering::lowerCall. This allows us to handle
situations where the calling convetion of the callee is different from
that of the caller.
Differential Revision: https://reviews.llvm.org/D31039
llvm-svn: 298254
Folding instructions when selecting can cause them to become dead.
Don't select these dead instructions (if they don't have other side
effects, and don't define physical registers).
Preserve existing tests by adding COPYs.
In some tests, the G_CONSTANT vregs never get constrained to a class:
the only use of the vreg was folded into another instruction, so the
G_CONSTANT, now dead, never gets selected.
llvm-svn: 298224
Currently, we create a G_CONSTANT for every "synthetic" integer
constant operand (for instance, for the G_GEP offset).
Instead, share the G_CONSTANTs we might have created by going through
the ValueToVReg machinery.
When we're emitting synthetic constants, we do need to get Constants from
the context. One could argue that we shouldn't modify the context at
all (for instance, this means that we're going to use a tad more memory
if the constant wasn't used elsewhere), but constants are mostly
harmless. We currently do this for extractvalue and all.
For constant fcmp, this does mean we'll emit an extra COPY, which is not
necessarily more optimal than an extra materialized constant.
But that preserves the current intended design of uniqued G_CONSTANTs,
and the rematerialization problem exists elsewhere and should be
resolved with a single coherent solution.
llvm-svn: 297875
Now that we preserve the IR layout, we would end up with all the newly
synthesized switch comparison blocks at the end of the function.
Instead, use a hopefully more reasonable layout, with the comparison
blocks immediately following the switch comparison blocks.
llvm-svn: 297869
It makes the output function layout more predictable; the layout has
an effect on performance, we don't want it to be at the mercy of the
translator's visitation order and such.
The predictable output is also easier to digest.
getOrCreateBB isn't appropriately named anymore, as it never needs to
create anything. Rename it and extract the MBB creation logic out of it.
A couple tests were sensitive to the order. Update them.
llvm-svn: 297868
Summary:
<1 x Ty> is not a legal vector type in LLT, we shouldn’t build G_MERGE_VALUES
instruction for them.
Reviewers: qcolombet, aditya_nandakumar, dsanders, t.p.northover, ab, javed.absar
Reviewed By: qcolombet
Subscribers: dberris, rovka, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D30948
llvm-svn: 297792
We don't need to check whether the fallback path is enabled to return
false. Just do that all the time on error cases, the caller knows (or
at least should know!) how to handle the failing case.
llvm-svn: 297535
Summary: No test case as none of the in-tree targets with GlobalISel support has this condition.
Reviewers: qcolombet, aditya_nandakumar, dsanders, t.p.northover, ab
Reviewed By: qcolombet
Subscribers: dberris, rovka, kristof.beyls, llvm-commits, igorb
Differential Revision: https://reviews.llvm.org/D30786
llvm-svn: 297512
Summary:
We don’t actually use LegalizerInfo in Legalizer pass, it’s just passed
as an argument.
In order to check if an instruction is legal or not, we need to get LegalizerInfo
by calling `MI.getParent()->getParent()->getSubtarget().getLegalizerInfo()`.
Instead, make LegalizerInfo accessible in LegalizerHelper.
Reviewers: qcolombet, aditya_nandakumar, dsanders, ab, t.p.northover, kristof.beyls
Reviewed By: qcolombet
Subscribers: dberris, llvm-commits, rovka
Differential Revision: https://reviews.llvm.org/D30838
llvm-svn: 297491
The good reason to do this is that static allocas are pretty simple to handle
(especially at -O0) and avoiding tracking DBG_VALUEs throughout the pipeline
should give some kind of performance benefit.
The bad reason is that the debug pipeline is an unholy mess of implicit
contracts, where determining whether "DBG_VALUE %reg, imm" actually implies a
load or not involves the services of at least 3 soothsayers and the sacrifice
of at least one chicken. And it still gets it wrong if the variable is at SP
directly.
llvm-svn: 297410
Summary:
This will allow future patches to inspect the details of the LLT. The implementation is now split between
the Support and CodeGen libraries to allow TableGen to use this class without introducing layering concerns.
Thanks to Ahmed Bougacha for finding a reasonable way to avoid the layering issue and providing the version of this patch without that problem.
The problem with the previous commit appears to have been that TableGen was including CodeGen/LowLevelType.h instead of Support/LowLevelTypeImpl.h.
Reviewers: t.p.northover, qcolombet, rovka, aditya_nandakumar, ab, javed.absar
Subscribers: arsenm, nhaehnle, mgorny, dberris, llvm-commits, kristof.beyls
Differential Revision: https://reviews.llvm.org/D30046
llvm-svn: 297241
We were calculating incorrect extract/insert offsets by trying to be too
tricksy with min/max. It's clearer to just split the logic up into "register
starts before this segment" vs "after".
llvm-svn: 297226
Some intrinsics take metadata parameters. These all need custom
handling of some form, and cannot possibly be lowered generically to
G_INTRINSIC calls with vreg operands.
Reject them, instead of hitting an assert later in getOrCreateVReg.
llvm-svn: 297209
When we translate a no-op (same type) bitcast, we try to be clever and
only emit a COPY if we already assigned a vreg to the defined value.
However, when we didn't, we tried to assign to a reference into the
ValToVReg DenseMap, even though the RHS of the assignment
(getOrCreateVReg) could potentially grow that DenseMap, invalidating the
reference.
Avoid that by getting the source vreg first.
I audited the rest of the translator; this is the only tricky case.
The test is quite unwieldy, as the problem is caused by the DenseMap
growing, which happens after the 47th mapped value.
llvm-svn: 297208
For vector operands, the `select` instruction supports both vector and
non-vector conditions. The MIR builder had an overly restrictive
assertion, that only accepted vector conditions for vector selects
(in effect implementing ISD::VSELECT).
Make it possible to express the full range of G_SELECTs.
llvm-svn: 297207
When computing the mapping for non-generic instructions, we skipped
%noreg operands, because we can't always reason about their banks.
Also skip them when applying the mapping. Otherwise, we could end
up with mappings that we can't apply.
While there, duplicate an assert to distinguish between the two
error conditions.
llvm-svn: 297201
When a dbg_value has a constant operand that isn't representable in MI,
there isn't much we can do. Use %noreg (0) for those situations.
This matches the SelectionDAG behavior.
llvm-svn: 297200
Daniel Sanders