Adds a new backend to power the GISel Combiners using the InstructionSelector's match tables.
This does not depend on any of the data structures created for the current combiner and is intended to replace it entirely.
See the RFC for more details: https://discourse.llvm.org/t/rfc-matchtable-based-globalisel-combiners/71457/6
Note: this would replace D141135.
Reviewed By: aemerson, arsenm
Differential Revision: https://reviews.llvm.org/D153757
Move all of the reusable logic out of `GlobalISelEmitter.cpp` into a `GlobalISelMatchTableExecutorEmitter` class so the future combiner backend can use it as well.
Depends on D153755
Reviewed By: aemerson
Differential Revision: https://reviews.llvm.org/D153756
Makes `InstructionSelector.h`/`InstructionSelectorImpl.h` generic so the match tables can also be used for the combiner.
Some notes:
- Coverage was made an optional parameter of `executeMatchTable`, combines won't use it for now.
- `GIPFP_` -> `GICXXPred_` so it's more generic. Those are just C++ predicates and aren't PatFrag-specific.
- Pass the MatcherState directly to testMIPredicate_MI, the combiner will need it.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D153755
This patch splits the GlobalISelEmitter.cpp file, which imports DAG ISel patterns for GISel, into separate "GISelMatchTable.h/cpp" files.
The main motive is readability & maintainability. GlobalISelEmitter.cpp was about 6400 lines of mixed code, some bits implementing the match table codegen, some others dedicated to importing DAG patterns.
Now it's down to 2700 + a 2150 header + 2000 impl.
It's a tiny bit more lines overall but that's to be expected - moving
inline definitions to out-of-line, adding comments in the .cpp, etc. all of that takes additional space, but I think the tradeoff is worth it.
I did as little unrelated code changes as possible, I would say the biggest change is the introduction of the `gi` namespace used to prevent name conflicts/ODR violations with type common names such as `Matcher`.
It was previously not an issue because all of the code was in an anonymous namespace.
This moves all of the "match table" code out of the file, so predicates,
rules, and actions are all separated now. I believe this helps separating concerns, now `GlobalISelEmitter.cpp` is more focused on importing DAG patterns into GI, instead of also containing the whole match table internals as well.
Note: the new files have a "GISel" prefix to make them distinct from the other "GI" files in the same folder, which are for the combiner.
Reviewed By: aemerson
Differential Revision: https://reviews.llvm.org/D151432
This patch splits the GlobalISelEmitter.cpp file, which imports DAG ISel patterns for GISel, into separate "GISelMatchTable.h/cpp" files.
The main motive is readability & maintainability. GlobalISelEmitter.cpp was about 6400 lines of mixed code, some bits implementing the match table codegen, some others dedicated to importing DAG patterns.
Now it's down to 2700 + a 2150 header + 2000 impl.
It's a tiny bit more lines overall but that's to be expected - moving
inline definitions to out-of-line, adding comments in the .cpp, etc. all of that takes additional space, but I think the tradeoff is worth it.
I did as little unrelated code changes as possible, I would say the biggest change is the introduction of the `gi` namespace used to prevent name conflicts/ODR violations with type common names such as `Matcher`.
It was previously not an issue because all of the code was in an anonymous namespace.
This moves all of the "match table" code out of the file, so predicates,
rules, and actions are all separated now. I believe this helps separating concerns, now `GlobalISelEmitter.cpp` is more focused on importing DAG patterns into GI, instead of also containing the whole match table internals as well.
Note: the new files have a "GISel" prefix to make them distinct from the other "GI" files in the same folder, which are for the combiner.
Reviewed By: aemerson
Differential Revision: https://reviews.llvm.org/D151432
This is rework of;
- rG13e77db2df94 (r328395; MVT)
Since `LowLevelType.h` has been restored to `CodeGen`, `MachinveValueType.h`
can be restored as well.
Depends on D148767
Differential Revision: https://reviews.llvm.org/D149024
This is rework of;
- D30046 (LLT)
Since I have introduced `llvm-min-tblgen` as D146352, `llvm-tblgen`
may depend on `CodeGen`.
`LowLevlType.h` originally belonged to `CodeGen`. Almost all userse are
still under `CodeGen` or `Target`. I think `CodeGen` is the right place
to put `LowLevelType.h`.
`MachineValueType.h` may be moved as well. (later, D149024)
I have made many modules depend on `CodeGen`. It is consistent but
inefficient. It will be split out later, D148769
Besides, I had to isolate MVT and LLT in modmap, since
`llvm::PredicateInfo` clashes between `TableGen/CodeGenSchedule.h`
and `Transforms/Utils/PredicateInfo.h`.
(I think better to introduce namespace llvm::TableGen)
Depends on D145937, D146352, and D148768.
Differential Revision: https://reviews.llvm.org/D148767
There are some patterns in td files without MVT/class set
for some operands in target pattern that are from the source
pattern. This prevents GlobalISelEmitter from adding them as
a valid rule, because the target child operand is an
unsupported kind operand. For now, for a leaf child, only
IntInit and DefInit are handled in GlobalISelEmitter.
This issue can be workaround by adding MVT/class to the
patterns in the td files, like the workarounds for patterns
anyext and setcc in PPCInstrInfo.td in D140878.
To avoid adding the same workarounds for other patterns in
td files, this patch tries to handle the UnsetInit case in
GlobalISelEmitter.
Adding the new handling allows us to remove the workarounds
in the td files and also generates many selection rules for
PPC target.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D141247
This makes it possible to write GlobalISel patterns generating
EXTRACT_SUBREG instructions applied to suboperands of ComplexPattern
operands. Currently, TableGen complains that such operands are not
declared in matcher.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D146800
RFC to add a way to ignore COPY instructions when pattern-matching MIR in GISel.
- Add a new "GISelFlags" class to TableGen. Both `Pattern` and `PatFrags` defs can use it to alter matching behaviour.
- Flags start at zero and are scoped: the setter returns a `SaveAndRestore` object so that when the current scope ends, the flags are restored to their previous values. This allows child patterns to modify the flags without affecting the parent pattern.
- Child patterns always reuse the parent's pattern, but they can override its values. For more examples, see `GlobalISelEmitterFlags.td` tests.
- [AMDGPU] Use the IgnoreCopies flag in BFI patterns, which are known to be bothered by cross-regbank copies.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D136234
Use deduction guides instead of helper functions.
The only non-automatic changes have been:
1. ArrayRef(some_uint8_pointer, 0) needs to be changed into ArrayRef(some_uint8_pointer, (size_t)0) to avoid an ambiguous call with ArrayRef((uint8_t*), (uint8_t*))
2. CVSymbol sym(makeArrayRef(symStorage)); needed to be rewritten as CVSymbol sym{ArrayRef(symStorage)}; otherwise the compiler is confused and thinks we have a (bad) function prototype. There was a few similar situation across the codebase.
3. ADL doesn't seem to work the same for deduction-guides and functions, so at some point the llvm namespace must be explicitly stated.
4. The "reference mode" of makeArrayRef(ArrayRef<T> &) that acts as no-op is not supported (a constructor cannot achieve that).
Per reviewers' comment, some useless makeArrayRef have been removed in the process.
This is a follow-up to https://reviews.llvm.org/D140896 that introduced
the deduction guides.
Differential Revision: https://reviews.llvm.org/D140955
value() has undesired exception checking semantics and calls
__throw_bad_optional_access in libc++. Moreover, the API is unavailable without
_LIBCPP_NO_EXCEPTIONS on older Mach-O platforms (see
_LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS).
This commit fixes LLVMAnalysis and its dependencies.
It is generally good practice, if you know how big the vector is going to be in the end, to reserve before continually calling "push_back" or "emplace_back"
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D139483
This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated. The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.
This is part of an effort to migrate from
llvm::Optional to std::optional:
https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
Without it, the count of renderer functions is inaccurate and, in some
edge cases (like the patterns added in D134354), we can actually
go out of bounds (run out of pre-allocated renderer function spaces
in the GISel state)
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D134861
Allows things like `(G_PTR_ADD (G_PTR_ADD a, b), c)` to be
simplified into a single ADD3 instruction instead of two adds.
Reviewed By: foad
Differential Revision: https://reviews.llvm.org/D131254
SelectionDAG has a target hook, getExtendForAtomicOps, which it uses
in the computeKnownBits implementation for ATOMIC_LOAD. This is pretty
ugly (as is having a separate load opcode for atomics), so instead
allow making use of atomic zextload. Enable this for AArch64 since the
DAG path defaults in to the zext behavior.
The tablegen changes are pretty ugly, but partially helps migrate
SelectionDAG from using ISD::ATOMIC_LOAD to regular ISD::LOAD with
atomic memory operands. For now the DAG emitter will emit matchers for
patterns which the DAG will not produce.
I'm still a bit confused by the intent of the isLoad/isStore/isAtomic
bits. The DAG implementation rejects trying to use any of these in
combination. For now I've opted to make the isLoad checks also check
isAtomic, although I think having isLoad and isAtomic set on these
makes most sense.
This change introduces the HasNoUse builtin predicate in PatFrags that
checks for the absence of use of the first result operand.
GlobalISelEmitter will allow source PatFrags with this predicate to be
matched with destination instructions with empty outs. This predicate is
required for selecting the no-return variant of atomic instructions in
AMDGPU.
Differential Revision: https://reviews.llvm.org/D125212
The builtin predicate handling has a strange behavior where the code
assumes that a PatFrag is a stack of PatFrags, and each level adds at
most one predicate. I don't think this particularly makes sense,
especially without a diagnostic to ensure you aren't trying to set
multiple at once.
This wasn't followed for address spaces and alignment, which could
potentially fall through to report no builtin predicate was
added. Just switch these to follow the existing convention for now.
Add void casts to mark the variables used, next to the places where
they are used in assert or `LLVM_DEBUG()` expressions.
Differential Revision: https://reviews.llvm.org/D123117
Based on the output of include-what-you-use.
It's an utility directory, so no much impact on other code areas.
clang++ -E -Iinclude -I../llvm/include ../llvm/utils/TableGen/*.cpp -std=c++14 -fno-rtti -fno-exceptions | wc -l
before: 4327274
after: 4316190
Related discourse thread: https://llvm.discourse.group/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D118466
