Since `raw_string_ostream` doesn't own the string buffer, it is
desirable (in terms of memory safety) for users to directly reference
the string buffer rather than use `raw_string_ostream::str()`.
Work towards TODO comment to remove `raw_string_ostream::str()`.
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
For instructions that don't map to a mnemonic string, the implementation
of MCInstPrinter::getMnemonic would return an invalid pointer due to the
result of the calculation of the instruction's position in the `AsmStrs`
table. This patch fixes the issue by ensuring those cases return a
`nullptr` value instead.
Fixes#74177.
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
LLVM contains a helpful function for getting the size of a C-style
array: `llvm::array_lengthof`. This is useful prior to C++17, but not as
helpful for C++17 or later: `std::size` already has support for C-style
arrays.
Change call sites to use `std::size` instead.
Differential Revision: https://reviews.llvm.org/D133429
This is used by disassemblers: `llvm-mc -disassemble -mattr=` and `llvm-objdump --mattr=`.
The main use case is for llvm-objdump to disassemble all known instructions
(D128030).
In user-facing tools, "all" is intentionally not supported in producers:
integrated assembler (`.arch_extension all`), clang -march (`-march=armv9.3a+all`).
Due to the code structure, `llvm-mc -mattr=+all` `llc -mattr=+all` are not
rejected (they are internal tool). Add `llvm/test/CodeGen/AArch64/mattr-all.ll`
to catch behavior changes.
AArch64SysReg::SysReg::haveFeatures: check `FeatureAll` to print
`AArch64SysReg::SysReg::AltName` for some system registers (e.g. `ERRIDR_EL1, RNDR`).
AArch64.td: add `AssemblerPredicateWithAll` to additionally test `FeatureAll`.
Change all `AssemblerPredicate` (except `UseNegativeImmediates`) to `AssemblerPredicateWithAll`.
utils/TableGen/{DecoderEmitter,SubtargetFeatureInfo}.cpp: support arbitrarily
nested all_of, any_of, and not.
Note: A predicate supports all_of, any_of, and not. For a target (though
currently not for AArch64) an encoding may be disassembled differently with
different target features.
Note: AArch64MCCodeEmitter::computeAvailableFeatures is not available to
the disassembler.
Reviewed By: peter.smith, lenary
Differential Revision: https://reviews.llvm.org/D128029
The mask being NoRegister prevented the existing aliases from matching
since NoRegister isn't in the VMV0 register class.
To workaround this I've added new aliases that look for zero_reg.
I had to motify tablegen to generate matching code for zero_reg.
And as a consequence, I had to change the EmitPriority for an ARM
alias that used zero_reg that started printing.
Reviewed By: frasercrmck
Differential Revision: https://reviews.llvm.org/D121496
This reverts commit ef8206320769ad31422a803a0d6de6077fd231d2.
- It conflicts with the existing llvm::size in STLExtras, which will now
never be called.
- Calling it without llvm:: breaks C++17 compat
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.
We are seeing extremely long time in building AMDGPUInstPrinter.cpp
when profile instrumentation is enabled: It takes more than 5 minutes
(compared to ~8 seconds in non-instrument build).
This caused by the huge statements in printInstruction functions. In
profile instrumentation build, we need have extra control flow to
differentiate each case statement. This in turn adds significant
compile time in block placement and branch folding.
Function printInstruction is not likely to benefit from PGO build
as it's rarely executed in a typical compilation. So here I disable
the profile instrumentation for this function.
Differential Revision: https://reviews.llvm.org/D111682
This patch factors out the part of printInstruction that gets the
mnemonic string for a given MCInst. This is intended to be used
subsequently for the instruction-mix remarks to display the final
mnemonic (D90040).
Unfortunately making `getMnemonic` available to the AsmPrinter
seems to require making it virtual. Not sure if there's a way around
that with the current layering of the AsmPrinters.
Reviewed By: Paul-C-Anagnostopoulos
Differential Revision: https://reviews.llvm.org/D90039
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
Summary:
TableGen interprets braces ('{}') in the asm string of instruction aliases as
variants but when defining aliases with literal braces they have to be escaped
to prevent them being removed.
Braces are escaped with '\\', for example:
def FooBraces : InstAlias<"foo \\{$imm\\}", (foo IntOperand:$imm)>;
Although when TableGen is emitting the assembly writer (-gen-asm-writer)
the AsmString that gets emitted is:
AsmString = "foo \{$\x01\}";
In c/c++ braces don't need to be escaped which causes compilation
warnings:
warning: use of non-standard escape character '\{' [-Wpedantic]
This patch fixes the issue by unescaping the flattened alias asm string
in the asm writer, by replacing '\{\}' with '{}'.
Reviewed By: hfinkel
Differential Revision: https://reviews.llvm.org/D79991
For context, the proposed RISC-V bit manipulation extension has a subset
of instructions which require one of two SubtargetFeatures to be
enabled, 'zbb' or 'zbp', and there is no defined feature which both of
these can imply to use as a constraint either (see comments in D65649).
AssemblerPredicates allow multiple SubtargetFeatures to be declared in
the "AssemblerCondString" field, separated by commas, and this means
that the two features must both be enabled. There is no equivalent to
say that _either_ feature X or feature Y must be enabled, short of
creating a dummy SubtargetFeature for this purpose and having features X
and Y imply the new feature.
To solve the case where X or Y is needed without adding a new feature,
and to better match a typical TableGen style, this replaces the existing
"AssemblerCondString" with a dag "AssemblerCondDag" which represents the
same information. Two operators are defined for use with
AssemblerCondDag, "all_of", which matches the current behaviour, and
"any_of", which adds the new proposed ORing features functionality.
This was originally proposed in the RFC at
http://lists.llvm.org/pipermail/llvm-dev/2020-February/139138.html
Changes to all current backends are mechanical to support the replaced
functionality, and are NFCI.
At this stage, it is illegal to combine features with ands and ors in a
single AssemblerCondDag. I suspect this case is sufficiently rare that
adding more complex changes to support it are unnecessary.
Differential Revision: https://reviews.llvm.org/D74338
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.
This changes the generated (Instr|Asm|Reg|Regclass)Name tables from this
form:
extern const char HexagonInstrNameData[] = {
/* 0 */ 'G', '_', 'F', 'L', 'O', 'G', '1', '0', 0,
/* 9 */ 'E', 'N', 'D', 'L', 'O', 'O', 'P', '0', 0,
/* 18 */ 'V', '6', '_', 'v', 'd', 'd', '0', 0,
/* 26 */ 'P', 'S', '_', 'v', 'd', 'd', '0', 0,
[...]
};
...to this:
extern const char HexagonInstrNameData[] = {
/* 0 */ "G_FLOG10\0"
/* 9 */ "ENDLOOP0\0"
/* 18 */ "V6_vdd0\0"
/* 26 */ "PS_vdd0\0"
[...]
};
This should make debugging and exploration a lot easier for mortals,
while providing a significant compile-time reduction for common compilers.
To avoid issues with low implementation limits, this is disabled by
default for visual studio.
To force output one way or the other, pass
`--long-string-literals=<bool>` to `tablegen`
Reviewers: mstorsjo, rnk
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D73044
A variation of this patch was originally committed in ce23515f5ab011 and
then reverted in e464b31c due to build failures.
This changes the generated (Instr|Asm|Reg|Regclass)Name tables from this
form:
extern const char HexagonInstrNameData[] = {
/* 0 */ 'G', '_', 'F', 'L', 'O', 'G', '1', '0', 0,
/* 9 */ 'E', 'N', 'D', 'L', 'O', 'O', 'P', '0', 0,
/* 18 */ 'V', '6', '_', 'v', 'd', 'd', '0', 0,
/* 26 */ 'P', 'S', '_', 'v', 'd', 'd', '0', 0,
[...]
};
...to this:
extern const char HexagonInstrNameData[] = {
/* 0 */ "G_FLOG10\0"
/* 9 */ "ENDLOOP0\0"
/* 18 */ "V6_vdd0\0"
/* 26 */ "PS_vdd0\0"
[...]
};
This should make debugging and exploration a lot easier for mortals,
while providing a significant compile-time reduction for common compilers.
To avoid issues with low implementation limits, this is disabled by
default for visual studio or when cross-compiling.
To force output one way or the other, pass
`--long-string-literals=<bool>` to `tablegen`
Reviewers: mstorsjo, rnk
Subscribers: llvm-commit
Differential Revision: https://reviews.llvm.org/D73044
Before this change, the *InstPrinter.cpp files of each target where some
of the slowest objects to compile in all of LLVM. See this snippet produced by
ClangBuildAnalyzer:
https://reviews.llvm.org/P8171$96
Search for "InstPrinter", and see that it shows up in a few places.
Tablegen was emitting a large switch containing a sequence of operand checks,
each of which created many conditions and many BBs. Register allocation and
jump threading both did not scale well with such a large repetitive sequence of
basic blocks.
So, this change essentially turns those control flow structures into
data. The previous structure looked like:
switch (Opc) {
case TGT::ADD:
// check alias 1
if (MI->getOperandCount() == N && // check num opnds
MI->getOperand(0).isReg() && // check opnd 0
...
MI->getOperand(1).isImm() && // check opnd 1
AsmString = "foo";
break;
}
// check alias 2
if (...)
...
return false;
The new structure looks like:
OpToPatterns: Sorted table of opcodes mapping to pattern indices.
\->
Patterns: List of patterns. Previous table points to subrange of
patterns to match.
\->
Conds: The if conditions above encoded as a kind and 32-bit value.
See MCInstPrinter.cpp for the details of how the new data structures are
interpreted.
Here are some before and after metrics.
Time to compile AArch64InstPrinter.cpp:
0m29.062s vs. 0m2.203s
size of the obj:
3.9M vs. 676K
size of clang.exe:
97M vs. 96M
I have not benchmarked disassembly performance, but typically
disassemblers are bottlenecked on IO and string processing, not alias
matching, so I'm not sure it's interesting enough to be worth doing.
Reviewers: RKSimon, andreadb, xbolva00, craig.topper
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D70650
Summary:
While working with DagInit's, it's often the case that you expect the
operator to be a reference to a def. This patch adds a wrapper for this
common case to reduce the amount of boilerplate callers need to duplicate
repeatedly.
getOperatorAsDef() returns the record if the DagInit has an operator that is
a DefInit. Otherwise, it prints a fatal error.
There's only a few pre-existing examples in LLVM at the moment and I've
left a few instances of the code this simplifies as they had more specific
error messages than the generic one this produces. I'm going to be using
this a fair bit in my subsequent patches.
Reviewers: bogner, volkan, nhaehnle
Reviewed By: nhaehnle
Subscribers: nhaehnle, hiraditya, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, lenary, s.egerton, pzheng, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68424
llvm-svn: 374101
The --disassembler-options, or -M, are used to customize
the disassembler and affect its output.
The two implemented options allow selecting register names on ARM:
* With -Mreg-names-raw, the disassembler uses rNN for all registers.
* With -Mreg-names-std it prints sp, lr and pc for r13, r14 and r15,
which is the default behavior of llvm-objdump.
Differential Revision: https://reviews.llvm.org/D57680
llvm-svn: 354870
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