Code cleanups for TableGen files, changes includes function names,
variable names and unused imports.
---------
Co-authored-by: Matt Arsenault <Matthew.Arsenault@amd.com>
1. Bitwise operations are used to access HwMode, allowing for the
coexistence of HwMode IDs for different features (such as RegInfo and
EncodingInfo). This will provide better scalability for HwMode.
Currently, most users utilize HwMode primarily for configuring
Register-related information, and few use it for configuring Encoding.
The limited scalability of HwMode has been a significant factor in this
usage pattern.
2. Sink the HwMode Encodings selection logic down to per instruction
level, this makes the logic for choosing encodings clearer and provides
better error messages.
3. Add some HwMode ID conflict detection to the getHwMode() interface.
Refactor of the llvm-tblgen source into:
- a "Basic" library, which contains the bare minimum utilities to build
`llvm-min-tablegen`
- a "Common" library which contains all of the helpers for TableGen
backends. Such helpers can be shared by more than one backend, and even
unit tested (e.g. CodeExpander is, maybe we can add more over time)
Fixes#80647
DecoderEmitter and CodeEmitterGen perform repeated linear walks over the
entire instruction list. This patch eliminates two more such walks.
The eliminated traversals visit every instruction merely to determine
whether the target has variable length encodings. For a target with
variable length encodings, the original any_of will terminate quickly.
But all targets other than M68k use fixed length encodings and thus
any_of must visit the entire instruction list.
Currently the decoder and encoder emitters will crash if DefaultMode is
used within an EncodingByHwMode. As can be done today for
RegInfoByHwMode and ValueTypeByHwMode, this patch adds support for this
usage in EncodingByHwMode:
let EncodingInfos =
EncodingByHwMode<[ModeA, DefaultMode], [EncA, EncDefault]>;
getOperandBitOffset() causes the following warning on MSVC:
E:\llvm\ninja\lib\Target\SystemZ\SystemZGenMCCodeEmitter.inc(15414): warning C4060: switch statement contains no 'case' or 'default' labels
Do not emit empty OpNum switches.
Reviewed By: RKSimon, uweigand
Differential Revision: https://reviews.llvm.org/D155805
In order to generate relocations or to apply fixups after the layout
has been computed, the targets need to know the offsets of the
respective operands. There are indirect ways to figure them out in some
cases, for example, on SystemZ, the first memory operand is always at
offset 2, and the second one is always at offset 4. But there are no
such tricks for the immediate operands on SystemZ, so one has to refer
to individual instruction encodings.
This information, however, is available to TableGen. Generate
the getOperandBitOffset() method to access it, and use it to simplify
getting memory operand offsets on SystemZ. This also paves the way for
implementing symbolic immediates on this platform.
For the multi-lit operands, getOperandBitOffset() returns the offset of
the first lit.
An alternative way to obtain offsets would be to pass them to the
encoder methods, but this would require reworking all targets. Also,
VarLenCodeEmitter already does this, but adopting it requires
reworking the respective targets without other significant benefits.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D155329
After the work in a538d1f13a13 5351878ba196 372240dfe3d5, and
subsequently cleanup of all the in-tree targets, we can now delete the
support for positional operand matching!
This removes three options which could previously be set in a
Target's "InstrInfo" tablegen definition:
- useDeprecatedPositionallyEncodedOperands
- decodePositionallyEncodedOperands
- noNamedPositionallyEncodedOperands
(Also announced at https://discourse.llvm.org/t/tablegen-deleting-deprecated-positional-instruction-operand-matching-support/68524)
Differential Revision: https://reviews.llvm.org/D144210
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
Commit a538d1f13a13 first added support for named sub-operands in
CodeEmitterGen. We now add a few more features to that, enabling
further target cleanups.
1. Adds support for handling an EncoderMethod in a sub-operand in
CodeEmitterGen. Previously, the specified encoder of a sub-operand was
ignored, and only the default used.
2. Adds support for sub-operands in DecoderEmitter, along with support
for tied sub-operands.
The changes to the decoder required a few minor tweaks to a few
targets, where existing brokeness was exposed. In order to keep this
patch small, I left FIXMEs which will be addressed in upcoming
patches. (Except MIPS16, since its object file emission/decoding is
totally broken).
Differential Revision: https://reviews.llvm.org/D137653
Summary:
The existing undefined-bitfield-to-operand matching behavior is very
hard to understand, due to the combination of positional and named
matching. This can make it difficult to track down a bug in a target's
instruction definitions.
Over the last decade, folks have tried to work-around this in various
ways, but it's time to finally ditch the positional matching. With
https://reviews.llvm.org/D131003, there are no longer cases that
_require_ positional matching, and it's time to start removing usage
and support for it.
Therefore: add a (default-false) option, and set it to true only in
those targets that require positional matching today. Subsequent
changes will start cleaning up additional in-tree targets.
NOTE TO OUT OF TREE TARGET MAINTAINERS:
If this change breaks your build, you may restore the previous
behavior simply by adding:
let useDeprecatedPositionallyEncodedOperands = 1;
to your target's InstrInfo tablegen definition. However, this is
temporary -- the option will be removed in the future.
If your target does not set 'decodePositionallyEncodedOperands', you
may thus start migrating to named operands. However, if you _do_
currently set that option, I recommend waiting until a subsequent
change lands, which adds decoder support for named sub-operands.
Differential Revision: https://reviews.llvm.org/D134073
These names can then be matched by name against 'bits' fields in a
record, to populate an instruction's encoding.
This does _not_ yet change DecoderEmitter to allow by-name matching of
sub-operands. Unlike the encoder, the decoder already defaulted to not
supporting positional matching, and backends had workarounds in place
for the missing decoding support.
Additionally, use this new capability to allow the ARM and AArch64
backends not to require any positional operand matching.
Differential Revision: https://reviews.llvm.org/D131003
D25618 added a method to verify the instruction predicates for an
emitted instruction, through verifyInstructionPredicates added into
<Target>MCCodeEmitter::encodeInstruction. This is a very useful idea,
but the implementation inside MCCodeEmitter made it only fire for object
files, not assembly which most of the llvm test suite uses.
This patch moves the code into the <Target>_MC::verifyInstructionPredicates
method, inside the InstrInfo. The allows it to be called from other
places, such as in this patch where it is called from the
<Target>AsmPrinter::emitInstruction methods which should trigger for
both assembly and object files. It can also be called from other places
such as verifyInstruction, but that is not done here (it tends to catch
errors earlier, but in reality just shows all the mir tests that have
incorrect feature predicates). The interface was also simplified
slightly, moving computeAvailableFeatures into the function so that it
does not need to be called externally.
The ARM, AMDGPU (but not R600), AVR, Mips and X86 backends all currently
show errors in the test-suite, so have been disabled with FIXME
comments.
Recommitted with some fixes for the leftover MCII variables in release
builds.
Differential Revision: https://reviews.llvm.org/D129506
This reverts commit e2fb8c0f4b940e0285ee36c112469fa75d4b60ff as it does
not build for Release builds, and some buildbots are giving more warning
than I saw locally. Reverting to fix those issues.
D25618 added a method to verify the instruction predicates for an
emitted instruction, through verifyInstructionPredicates added into
<Target>MCCodeEmitter::encodeInstruction. This is a very useful idea,
but the implementation inside MCCodeEmitter made it only fire for object
files, not assembly which most of the llvm test suite uses.
This patch moves the code into the <Target>_MC::verifyInstructionPredicates
method, inside the InstrInfo. The allows it to be called from other
places, such as in this patch where it is called from the
<Target>AsmPrinter::emitInstruction methods which should trigger for
both assembly and object files. It can also be called from other places
such as verifyInstruction, but that is not done here (it tends to catch
errors earlier, but in reality just shows all the mir tests that have
incorrect feature predicates). The interface was also simplified
slightly, moving computeAvailableFeatures into the function so that it
does not need to be called externally.
The ARM, AMDGPU (but not R600), AVR, Mips and X86 backends all currently
show errors in the test-suite, so have been disabled with FIXME
comments.
Differential Revision: https://reviews.llvm.org/D129506
For instructions wider than 64 bits the InstBits table is initialized in
64-bit chunks from APInt::getRawData, but it was being read with
LoadIntFromMemory which is byte-based.
Fix this by reading the table with the APInt constructor that takes an
ArrayRef to the raw data instead.
This is currently NFC for in-tree targets but fixes AMDGPU failures on
big-endian hosts that were caused by D126483 until it was reverted.
Differential Revision: https://reviews.llvm.org/D127195
Full write up:
https://gist.github.com/mshockwave/66e98d099256deefc062633909bb7b5b
The existing CodeEmitterGen infrastructure is unable to generate encoder
function for ISAs with variable-length instructions. This patch
introduces a new infrastructure to support variable-length instruction
encoding, including a new TableGen syntax for writing instruction
encoding directives and a new TableGen backend component,
VarLenCodeEmitterGen, built on top of CodeEmitterGen.
Differential Revision: https://reviews.llvm.org/D115128
Since 65b13610a5226b84889b923bae884ba395ad084d, raw_string_ostream has
been unbuffered by default. Based on an audit of llvm/utils/, this
commit removes every call to `raw_string_ostream::flush()` and any call
to `raw_string_ostream::str()` whose result is ignored or that doesn't
help with clarity.
I left behind a few calls to `str()`. In these cases, the underlying
std::string was declared pretty far away and never used again, whereas
stream recently had its last write. The code is easier to read as-is;
the no-op call to `flush()` inside `str()` isn't harmful, and when
https://reviews.llvm.org/D115421 lands it'll be gone anyway.
As described on D111049, we're trying to remove the <string> dependency from error handling. In most cases the plan is to use the Twine() variant directly but to reduce introducing additional headers for the generated files, I'm using the const char* variant here instead.
This fixes an instance of:
warning: cast from 'const unsigned long *' to 'unsigned char *' drops const qualifier [-Wcast-qual]
when compiling the generated MCCodeEmitter for an out-of-tree target
that uses the optional support for instruction widths > 64 bits.
Differential Revision: https://reviews.llvm.org/D97942
Switch some for loops to just use the begin()/end() implementations
in the InfoByHwMode struct.
Add a method to insert into the map for the one case that was
modifying the map directly.
Some of these were found by running clang-format over the generated
code, although that complains about far more issues than I have fixed
here.
Differential Revision: https://reviews.llvm.org/D90937
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.
This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.
This doesn't actually modify StringRef yet, I'll do that in a follow-up.
When an instruction has an encoding definition for only a subset of
the available HwModes, ensure we just avoid generating an encoding
rather than crash.
llvm-svn: 374150
Much like ValueTypeByHwMode/RegInfoByHwMode, this patch allows targets
to modify an instruction's encoding based on HwMode. When the
EncodingInfos field is non-empty the Inst and Size fields of the Instruction
are ignored and taken from EncodingInfos instead.
As part of this promote getHwMode() from TargetSubtargetInfo to MCSubtargetInfo.
This is NFC for all existing targets - new code is generated only if targets
use EncodingByHwMode.
llvm-svn: 372320
Summary:
Also fixup rL371928 for cases that occur on our out-of-tree backend
There were still quite a few intermediate APInts and this caused the
compile time of MCCodeEmitter for our target to jump from 16s up to
~5m40s. This patch, brings it back down to ~17s by eliminating pretty
much all of them using two new APInt functions (extractBitsAsZExtValue(),
insertBits() but with a uint64_t). The exact conditions for eliminating
them is that the field extracted/inserted must be <=64-bit which is
almost always true.
Note: The two new APInt API's assume that APInt::WordSize is at least
64-bit because that means they touch at most 2 APInt words. They
statically assert that's true. It seems very unlikely that someone
is patching it to be smaller so this should be fine.
Reviewers: jmolloy
Reviewed By: jmolloy
Subscribers: hiraditya, dexonsmith, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67686
llvm-svn: 372243
Some VLIW instruction sets are Very Long Indeed. Using uint64_t constricts the Inst encoding to 64 bits (naturally).
This change switches CodeEmitter to a mode that uses APInts when Inst's bitwidth is > 64 bits (NFC for existing targets).
When Inst.BitWidth > 64 the prototype changes to:
void TargetMCCodeEmitter::getBinaryCodeForInstr(const MCInst &MI,
SmallVectorImpl<MCFixup> &Fixups,
APInt &Inst,
APInt &Scratch,
const MCSubtargetInfo &STI);
The Inst parameter returns the encoded instruction, the Scratch parameter is used internally for manipulating operands and is exposed so that the underlying storage can be reused between calls to getBinaryCodeForInstr. The goal is to elide any APInt constructions that we can.
Similarly the operand encoding prototype changes to:
getMachineOpValue(const MCInst &MI, const MCOperand &MO, APInt &op, SmallVectorImpl<MCFixup> &Fixups, const MCSubtargetInfo &STI);
That is, the operand is passed by reference as APInt rather than returned as uint64_t.
To reiterate, this APInt mode is enabled only when Inst.BitWidth > 64, so this change is NFC for existing targets.
llvm-svn: 371928
This requires std::intializer_list to be a literal type, which it is
starting with C++14. The downside is that std::bitset is still not
constexpr-friendly so this change contains a re-implementation of most
of it.
Shrinks clang by ~60k.
llvm-svn: 369847
AMDGPU target run out of Subtarget feature flags hitting the limit of 64.
AssemblerPredicates uses at most uint64_t for their representation.
At the same time CodeGen has exhausted this a long time ago and switched
to a FeatureBitset with the current limit of 192 bits.
This patch completes transition to the bitset for feature bits extending
it to asm matcher and MC code emitter.
Differential Revision: https://reviews.llvm.org/D59002
llvm-svn: 355839
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Record::getValues returns ArrayRef which has a cast operator
to std::vector, as a result a temporary vector is created
if the type of the variable is const std::vector&
that is suboptimal in this case.
Differential revision: https://reviews.llvm.org/D34969
Test plan: make check-all
llvm-svn: 307063
Internally both these methods just return the result of getValue on either a StringInit or a CodeInit object. In both cases this returns a StringRef pointing to a string allocated in the BumpPtrAllocator so its not going anywhere. So we can just pass that StringRef along.
This is a fairly naive patch that targets just the build failures caused by this change. There's additional work that can be done to avoid creating std::string at call sites that still think getValueAsString returns a std::string. I'll try to clean those up in future patches.
Differential Revision: https://reviews.llvm.org/D33710
llvm-svn: 304325
Summary:
The SelectionDAG importer now imports rules with Predicate's attached via
Requires, PredicateControl, etc. These predicates are implemented as
bitset's to allow multiple predicates to be tested together. However,
unlike the MC layer subtarget features, each target only pays for it's own
predicates (e.g. AArch64 doesn't have 192 feature bits just because X86
needs a lot).
Both AArch64 and X86 derive at least one predicate from the MachineFunction
or Function so they must re-initialize AvailableFeatures before each
function. They also declare locals in <Target>InstructionSelector so that
computeAvailableFeatures() can use the code from SelectionDAG without
modification.
Reviewers: rovka, qcolombet, aditya_nandakumar, t.p.northover, ab
Reviewed By: rovka
Subscribers: aemerson, rengolin, dberris, kristof.beyls, llvm-commits, igorb
Differential Revision: https://reviews.llvm.org/D31418
llvm-svn: 300993
