Rework the `Option` library to reduce dynamic relocations (#119198)

Apologies for the large change, I looked for ways to break this up and
all of the ones I saw added real complexity. This change f

Rework the `Option` library to reduce dynamic relocations (#119198)

Apologies for the large change, I looked for ways to break this up and
all of the ones I saw added real complexity. This change focuses on the
option's prefixed names and the array of prefixes. These are present in
every option and the dominant source of dynamic relocations for PIE or
PIC users of LLVM and Clang tooling. In some cases, 100s or 1000s of
them for the Clang driver which has a huge number of options.

This PR addresses this by building a string table and a prefixes table
that can be referenced with indices rather than pointers that require
dynamic relocations. This removes almost 7k dynmaic relocations from the
`clang` binary, roughly 8% of the remaining dynmaic relocations outside
of vtables. For busy-boxing use cases where many different option tables
are linked into the same binary, the savings add up a bit more.

The string table is a straightforward mechanism, but the prefixes
required some subtlety. They are encoded in a Pascal-string fashion with
a size followed by a sequence of offsets. This works relatively well for
the small realistic prefixes arrays in use.

Lots of code has to change in order to land this though: both all the
option library code has to be updated to use the string table and
prefixes table, and all the users of the options library have to be
updated to correctly instantiate the objects.

Some follow-up patches in the works to provide an abstraction for this
style of code, and to start using the same technique for some of the
other strings here now that the infrastructure is in place.

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[OptTable] Make new lines in help text respect indentation (#75366)

With this changes, new lines in the HelpText defined in OptTable have
the same indentation as the first line.

Before, the help

[OptTable] Make new lines in help text respect indentation (#75366)

With this changes, new lines in the HelpText defined in OptTable have
the same indentation as the first line.

Before, the help output will look something like:

```
--color=<value> Whether to use color when
symbolizing log markup: always, auto, never
```

With this change:

```
--color=<value> Whether to use color when
symbolizing log markup: always, auto, never
```

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[test] Disable the -Wself-move warning that triggers on exactly what is being tested (NFC)

/Users/jiefu/llvm-project/llvm/unittests/Option/OptionParsingTest.cpp:251:6: error: explicitly moving varia

[test] Disable the -Wself-move warning that triggers on exactly what is being tested (NFC)

/Users/jiefu/llvm-project/llvm/unittests/Option/OptionParsingTest.cpp:251:6: error: explicitly moving variable of type 'InputArgList' to itself [-Werror,-Wself-move]
AL = std::move(AL);
~~ ^ ~~
1 error generated.

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Guard against self-assignment in InputArgList

The InputArgList move assignment operator releases memory before copying
fields, but it doesn't check against self-assignment. I haven't seen the
self-a

Guard against self-assignment in InputArgList

The InputArgList move assignment operator releases memory before copying
fields, but it doesn't check against self-assignment. I haven't seen the
self-assignment happen, but it doesn't look safe.

Differential Revision: https://reviews.llvm.org/D158134

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Hide `#pragma clang` behind ifdef guards to fix MSVC "unknown pragma 'clang'" warning. NFC.

[Driver] Refactor to use llvm Option's new Visibility flags

This is a big refactor of the clang driver's option handling to use
the Visibility flags introduced in https://reviews.llvm.org/D157149.
T

[Driver] Refactor to use llvm Option's new Visibility flags

This is a big refactor of the clang driver's option handling to use
the Visibility flags introduced in https://reviews.llvm.org/D157149.
There are a few distinct parts, but they can't really be split into
separate commits and still be made to compile.

1. We split out some of the flags in ClangFlags to ClangVisibility.
Note that this does not include any subtractive flags.

2. We update the Flag definitions and OptIn/OptOut constructs in
Options.td by hand.

3. We introduce and use a script, update_options_td_flags, to ease
migration of flag definitions in Options.td, and we run that on
Options.td. I intend to remove this later, but I'm committing it so
that downstream forks can use the script to simplify merging.

4. We update calls to OptTable in the clang driver, cc1as, flang, and
clangd to use the visibility APIs instead of Include/Exclude flags.

5. We deprecate the Include/Exclude APIs and add a release note.

*if you are running into conflicts with this change:*

Note that https://reviews.llvm.org/D157150 may also be the culprit and
if so it should be handled first.

The script in `clang/utils/update_options_td_flags.py` can help. Take
the downstream side of all conflicts and then run the following:

```
% cd clang/include/clang/Driver
% ../../../utils/update_options_td_flags.py Options.td > Options.td.new
% mv Options.td.new Options.td
```

This will hopefully be sufficient, please take a look at the diff.

Differential Revision: https://reviews.llvm.org/D157151

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Reapply "[Option] Add "Visibility" field and clone the OptTable APIs to use it"

This reverts commit 4e3b89483a6922d3f48670bb1c50a37f342918c6, with
fixes for places I'd missed updating in lld and lld

Reapply "[Option] Add "Visibility" field and clone the OptTable APIs to use it"

This reverts commit 4e3b89483a6922d3f48670bb1c50a37f342918c6, with
fixes for places I'd missed updating in lld and lldb. I've also
renamed OptionVisibility::Default to "DefaultVis" to avoid ambiguity
since the undecorated name has to be available anywhere Options.inc is
included.

Original message follows:

This splits OptTable's "Flags" field into "Flags" and "Visibility",
updates the places where we instantiate Option tables, and adds
variants of the OptTable APIs that use Visibility mask instead of
Include/Exclude flags.

We need to do this to clean up a bunch of complexity in the clang
driver's option handling - there's a whole slew of flags like
CoreOption, NoDriverOption, and FlangOnlyOption there today to try to
handle all of the permutations of flags that the various drivers need,
but it really doesn't scale well, as can be seen by things like the
somewhat recently introduced CLDXCOption.

Instead, we'll provide an additive model for visibility that's
separate from the other flags. For things like "HelpHidden", which is
used as a "subtractive" modifier for option visibility, we leave that
in "Flags" and handle it as a special case.

Note that we don't actually update the users of the Include/Exclude
APIs here or change the flags that exist in clang at all - that will
come in a follow up that refactors clang's Options.td to use the
increased flexibility this change allows.

Differential Revision: https://reviews.llvm.org/D157149

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Revert "[Option] Add "Visibility" field and clone the OptTable APIs to use it"

this is failing on bots, reverting to investigate.

This reverts commit a16104e6da6f36f3d72dbf53d10ba56495a0d65a.

[Option] Add "Visibility" field and clone the OptTable APIs to use it

This splits OptTable's "Flags" field into "Flags" and "Visibility",
updates the places where we instantiate Option tables, and a

[Option] Add "Visibility" field and clone the OptTable APIs to use it

This splits OptTable's "Flags" field into "Flags" and "Visibility",
updates the places where we instantiate Option tables, and adds
variants of the OptTable APIs that use Visibility mask instead of
Include/Exclude flags.

We need to do this to clean up a bunch of complexity in the clang
driver's option handling - there's a whole slew of flags like
CoreOption, NoDriverOption, and FlangOnlyOption there today to try to
handle all of the permutations of flags that the various drivers need,
but it really doesn't scale well, as can be seen by things like the
somewhat recently introduced CLDXCOption.

Instead, we'll provide an additive model for visibility that's
separate from the other flags. For things like "HelpHidden", which is
used as a "subtractive" modifier for option visibility, we leave that
in "Flags" and handle it as a special case.

Note that we don't actually update the users of the Include/Exclude
APIs here or change the flags that exist in clang at all - that will
come in a follow up that refactors clang's Options.td to use the
increased flexibility this change allows.

Differential Revision: https://reviews.llvm.org/D157149

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[llvm] Extract common `OptTable` bits into macros

All command-line tools using `llvm::opt` create an enum of option IDs and a table of `OptTable::Info` object. Most of the tools use the same ID (`OP

[llvm] Extract common `OptTable` bits into macros

All command-line tools using `llvm::opt` create an enum of option IDs and a table of `OptTable::Info` object. Most of the tools use the same ID (`OPT_##ID`), kind (`Option::KIND##Class`), group ID (`OPT_##GROUP`) and alias ID (`OPT_##ALIAS`). This patch extracts that common code into canonical macros. This results in fewer changes when tweaking the `OPTION` macros emitted by the TableGen backend.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D157028

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[Option] Explicitly specify all args in test. NFC

This doesn't really do anything but should simplify updating these
APIs in the near future.

[Option] Support special argument "--"

Many command line option implementations, including getopt_long and our
Support/CommandLine.cpp, support `--` as an end-of-option indicator. All
the subsequent

[Option] Support special argument "--"

Many command line option implementations, including getopt_long and our
Support/CommandLine.cpp, support `--` as an end-of-option indicator. All
the subsequent arguments are then treated as positional arguments.

D1387 added KIND_REMAINING_ARGS and 76ff1d915c9c42823a3f2b08ff936cf7a48933c5 dropped special handling of `--`.
Users need to add `def DASH_DASH : Option<["--"], "", KIND_REMAINING_ARGS>;` and
append `OPT_DASH_DASH` to the `OPT_INPUT` list., which is not ergonomic.

Restore this feature under an option and modify llvm-strings to utilize the
feature as an example. In the future, we probably should enable this feature by
default and exclude some tools that handle `DASH_DASH` differently (clang,
clang-scan-deps, etc. I suspect that many are workarounds for LLVMOption not
supporting `--` as a built-in feature).

Reviewed By: serge-sans-paille

Differential Revision: https://reviews.llvm.org/D152286

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[OptTable] Precompute OptTable prefixes union table through tablegen

This avoid rediscovering this table when reading each options, providing
a sensible 2% speedup when processing and empty file, an

[OptTable] Precompute OptTable prefixes union table through tablegen

This avoid rediscovering this table when reading each options, providing
a sensible 2% speedup when processing and empty file, and a measurable
speedup on typical workloads, see:

This is optional, the legacy, on-the-fly, approach can still be used
through the GenericOptTable class, while the new one is used through
PrecomputedOptTable.

https://llvm-compile-time-tracker.com/compare.php?from=4da6cb3202817ee2897d6b690e4af950459caea4&to=19a492b704e8f5c1dea120b9c0d3859bd78796be&stat=instructions:u

Differential Revision: https://reviews.llvm.org/D140800

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[clang] Use a StringRef instead of a raw char pointer to store builtin and call information

This avoids recomputing string length that is already known at compile time.

It has a slight impact on pr

[clang] Use a StringRef instead of a raw char pointer to store builtin and call information

This avoids recomputing string length that is already known at compile time.

It has a slight impact on preprocessing / compile time, see

https://llvm-compile-time-tracker.com/compare.php?from=3f36d2d579d8b0e8824d9dd99bfa79f456858f88&to=e49640c507ddc6615b5e503144301c8e41f8f434&stat=instructions:u

This a recommit of e953ae5bbc313fd0cc980ce021d487e5b5199ea4 and the subsequent fixes caa713559bd38f337d7d35de35686775e8fb5175 and 06b90e2e9c991e211fecc97948e533320a825470.

The above patchset caused some version of GCC to take eons to compile clang/lib/Basic/Targets/AArch64.cpp, as spotted in aa171833ab0017d9732e82b8682c9848ab25ff9e.
The fix is to make BuiltinInfo tables a compilation unit static variable, instead of a private static variable.

Differential Revision: https://reviews.llvm.org/D139881

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Revert "[clang] Use a StringRef instead of a raw char pointer to store builtin and call information"
Revert "Fix lldb option handling since e953ae5bbc313fd0cc980ce021d487e5b5199ea4 (part 2)"
Revert "

Revert "[clang] Use a StringRef instead of a raw char pointer to store builtin and call information"
Revert "Fix lldb option handling since e953ae5bbc313fd0cc980ce021d487e5b5199ea4 (part 2)"
Revert "Fix lldb option handling since e953ae5bbc313fd0cc980ce021d487e5b5199ea4"

GCC build hangs on this bot https://lab.llvm.org/buildbot/#/builders/37/builds/19104
compiling CMakeFiles/obj.clangBasic.dir/Targets/AArch64.cpp.d

The bot uses GNU 11.3.0, but I can reproduce locally with gcc (Debian 12.2.0-3) 12.2.0.

This reverts commit caa713559bd38f337d7d35de35686775e8fb5175.
This reverts commit 06b90e2e9c991e211fecc97948e533320a825470.
This reverts commit e953ae5bbc313fd0cc980ce021d487e5b5199ea4.

show more ...

[clang] Use a StringRef instead of a raw char pointer to store builtin and call information

This avoids recomputing string length that is already known at compile
time.

It has a slight impact on pr

[clang] Use a StringRef instead of a raw char pointer to store builtin and call information

This avoids recomputing string length that is already known at compile
time.

It has a slight impact on preprocessing / compile time, see

https://llvm-compile-time-tracker.com/compare.php?from=3f36d2d579d8b0e8824d9dd99bfa79f456858f88&to=e49640c507ddc6615b5e503144301c8e41f8f434&stat=instructions:u

This is a recommit of 719d98dfa841c522d8d452f0685e503538415a53 that into
account a GGC issue (probably
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92181) when dealing with
intiailizer_list and constant expressions.

Workaround this by avoiding initializer list, at the expense of a
temporary plain old array.

Differential Revision: https://reviews.llvm.org/D139881

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Revert "[clang] Use a StringRef instead of a raw char pointer to store builtin and call information"

There are still remaining issues with GCC 12, see for instance

https://lab.llvm.org/buildbot/#/b

Revert "[clang] Use a StringRef instead of a raw char pointer to store builtin and call information"

There are still remaining issues with GCC 12, see for instance

https://lab.llvm.org/buildbot/#/builders/93/builds/12669

This reverts commit 5ce4e92264102de21760c94db9166afe8f71fcf6.

show more ...

[clang] Use a StringRef instead of a raw char pointer to store builtin and call information

This avoids recomputing string length that is already known at compile
time.

It has a slight impact on pr

[clang] Use a StringRef instead of a raw char pointer to store builtin and call information

This avoids recomputing string length that is already known at compile
time.

It has a slight impact on preprocessing / compile time, see

https://llvm-compile-time-tracker.com/compare.php?from=3f36d2d579d8b0e8824d9dd99bfa79f456858f88&to=e49640c507ddc6615b5e503144301c8e41f8f434&stat=instructions:u

This is a recommit of 719d98dfa841c522d8d452f0685e503538415a53 with a
change to llvm/utils/TableGen/OptParserEmitter.cpp to cope with GCC bug
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108158

Differential Revision: https://reviews.llvm.org/D139881

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Revert "[clang] Use a StringRef instead of a raw char pointer to store builtin and call information"

Failing builds: https://lab.llvm.org/buildbot#builders/9/builds/19030
This is GCC specific and ha

Revert "[clang] Use a StringRef instead of a raw char pointer to store builtin and call information"

Failing builds: https://lab.llvm.org/buildbot#builders/9/builds/19030
This is GCC specific and has been reported upstream: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108158

This reverts commit 719d98dfa841c522d8d452f0685e503538415a53.

show more ...

[clang] Use a StringRef instead of a raw char pointer to store builtin and call information

This avoids recomputing string length that is already known at compile
time.

It has a slight impact on pr

[clang] Use a StringRef instead of a raw char pointer to store builtin and call information

This avoids recomputing string length that is already known at compile
time.

It has a slight impact on preprocessing / compile time, see

https://llvm-compile-time-tracker.com/compare.php?from=3f36d2d579d8b0e8824d9dd99bfa79f456858f88&to=e49640c507ddc6615b5e503144301c8e41f8f434&stat=instructions:u

Differential Revision: https://reviews.llvm.org/D139881

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Store OptTable::Info::Name as a StringRef

This is a recommit of 8ae18303f97d5dcfaecc90b4d87effb2011ed82e,
with a few cleanups.

This avoids implicit conversion to StringRef at several points, which

Store OptTable::Info::Name as a StringRef

This is a recommit of 8ae18303f97d5dcfaecc90b4d87effb2011ed82e,
with a few cleanups.

This avoids implicit conversion to StringRef at several points, which in
turns avoid redundant calls to strlen.

As a side effect, this greatly simplifies the implementation of
StrCmpOptionNameIgnoreCase.

It also eventually gives a consistent, humble speedup in compilation
time (timing updated since original commit).

https://llvm-compile-time-tracker.com/compare.php?from=de4b6a1bc64db33643f001ad45fae7b92b4a4688&to=c23a93d1292052b4be2fbe8c586fa31143d0c7ed&stat=instructions:u

Differential Revision: https://reviews.llvm.org/D139274

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[OptTable] Reapply Improve error message output for grouped short options

This reapplies 71d7fed3bc2ad6c22729d446526a59fcfd99bd03 which was
reverted by 3e2bd82f02c6cbbfb0544897c7645867f04b3a7e. This

[OptTable] Reapply Improve error message output for grouped short options

This reapplies 71d7fed3bc2ad6c22729d446526a59fcfd99bd03 which was
reverted by 3e2bd82f02c6cbbfb0544897c7645867f04b3a7e. This change
includes the fix for breaking the sanitizer bots.

As seen in https://bugs.llvm.org/show_bug.cgi?id=48880 the current
implementation for parsing grouped short options can return unclear
error messages. This change fixes the example given in the ticket in
which a flag is incorrectly given an argument. Also when parsing a
group we now keep reading past the first incorrect option and output
errors for all incorrect options in the group.

Differential Revision: https://reviews.llvm.org/D108770

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Revert "[OptTable] Improve error message output for grouped short options"

This reverts commit 71d7fed3bc2ad6c22729d446526a59fcfd99bd03.

Reason: broke sanitizer bots
more info: https://reviews.llvm

Revert "[OptTable] Improve error message output for grouped short options"

This reverts commit 71d7fed3bc2ad6c22729d446526a59fcfd99bd03.

Reason: broke sanitizer bots
more info: https://reviews.llvm.org/D108770

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[OptTable] Improve error message output for grouped short options

As seen in https://bugs.llvm.org/show_bug.cgi?id=48880 the current
implementation for parsing grouped short options can return uncle

[OptTable] Improve error message output for grouped short options

As seen in https://bugs.llvm.org/show_bug.cgi?id=48880 the current
implementation for parsing grouped short options can return unclear
error messages. This change fixes the example given in the ticket in
which a flag is incorrectly given an argument. Also when parsing a
group we now keep reading past the first incorrect option and output
errors for all incorrect options in the group.

Differential Revision: https://reviews.llvm.org/D108770

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[OptTable] Rename PrintHelp to printHelp

To be consistent with other member functions and match the coding standard.